Rpm Research Papers - Academia.edu (original) (raw)

- by and +1
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- Pharmaceutical Technology, Raman Spectroscopy, Pharmaceutical Chemistry, Near Infrared Spectroscopy

Classically, the end point detection during fluid bed drying has been performed using indirect parameters, such as the product temperature or the humidity of the outlet drying air. This paper aims at comparing those classic methods to both in-line moisture and solid-state determination by means of Process Analytical Technology (PAT) tools (Raman and NIR spectroscopy) and a mass balance approach. The six-segmented fluid bed drying system being part of a fully continuous from-powder-to-tablet production line (ConsiGma™-25) was used for this study. A theophylline:lactose:PVP (30:67.5:2.5) blend was chosen as model formulation. For the development of the NIR-based moisture determination model, 15 calibration experiments in the fluid bed dryer were performed. Six test experiments were conducted afterwards, and the product was monitored in-line with NIR and Raman spectroscopy during drying. The results (drying endpoint and residual moisture) obtained via the NIR-based moisture determination model, the classical approach by means of indirect parameters and the mass balance model were then compared. Our conclusion is that the PAT-based method is most suited for use in a production set-up. Secondly, the different size fractions of the dried granules obtained during different experiments (fines, yield and oversized granules) were compared separately, revealing differences in both solid state of theophylline and moisture content between the different granule size fractions.

- by Elisabeth Peeters and +1
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- Pharmaceutical Technology, Raman Spectroscopy, Pharmaceutical Chemistry, Near Infrared Spectroscopy

A common feature of all engines with internal combustion is the need for a gearbox. This constructive requirement is justified with the practical fact that, if the torque and power characteristics of an engine would be geared directly to the working bodies of a consumer machine (such as road wheels) it could not ensure enough torque throughout the vehicles operational speed range. According to the operational task that the vehicle should manage, several solutions are used. Automatic (planetary) gearboxes and CVTs (Continuously Variable Transmission) allow gear ratio changes without power interruption. In other cases such as race car technology, multiple ratio gearboxes are caused by rules and regulations. In order to optimise gearbox performance, a wide range of analytical methods are used. One of the most frequently used, is the traditional straight line plot of road speed against engine rpm (rounds per minute) as a method of choosing ratios. Unlike this method, tractive effort curves include much more information and so they can publish how well ratios are suited to the engine`s characteristics as well as the fundamental track parameters that driven their choice. This paper should state out the benefits of tractive effort curves in gearbox analyse. In order to maintain this, an instance from the Formula 1 was taken. Based on onboard video records of different tracks (in this example the tracks in Monaco and Monza were chosen), authors could approximately determine points of gear change and top speeds achieved within a certain ratio. These information allow to set a group of tractive effort curves (as well as several road speed – engine rpm diagrams). A huge amount of data, related not just to the gearbox, can be obtain when comparing results of these two methods and using them together.

- by Isad Saric
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- Gearbox, Formula 1, Tractive Effort Curves, Torque

Ethnopharmacological relevance: Traditional Chinese medicine (TCM) formulas have been widely used in China since ancient times to treat certain diseases (e.g., phlegm, dampness and blood stasis). Recently, the effects of these medicines have been increasingly demonstrated to be helpful for hyperlipidemic patients. Aim of the study: This manuscript aims to describe the scientific evidence for the efficacy of TCM and attempts to identify potential TCM formulas for treating hyperlipidemia. Materials and methods: TCM formulas approved by the State Food and Drug Administration of China (SFDA) were sourced from the official SFDA website (http://www.sda.gov.cn/). Human and animal evidence for the hypolipidemic effects of herbs from TCM formulas were reviewed via the Internet (Elsevier, ACS, Wiley Online Library, SpringerLink, PubMed, Web of Science, CNKI, Baidu, and Google) and libraries up to October 31, 2011. Results: More than 50 TCM formulas have been used to treat hyperlipidemia. These herbs can primarily be grouped into three categories: (1) herbs promoting excretions, generally by reducing food retention, enhancing purgative effects, and promoting diuresis and choleretic effects, e.g., Fructus Crataegi ( ), Radix Polygoni Multiflori ( ), Semen Cassiae ( ), and Radix et Rhizoma Rhei ( ), Rhizoma alismatis ( ), and Herba Artemisiae Scopariae ( ); (2) herbs acting on the cardiovascular system, generally by improving blood circulation based on TCM theories, e.g., Radix Salviae Miltiorrhizae ( ), Radix Puerariae ( ), Rhizoma Chuanxiong ( ), Flos Carthami ( ), and Folium Nelumbinis ( ); and (3) herbs that have tonic effects, e.g., Fructus Lycii ( ), Radix Ginseng ( ), and Radix Astragali (

In the present growing world of emerging technology, the micro machining process has demanding operation in various sectors like aerospace, oil, defence, automobile, biomedical science and many industries at micro and nano levels of manufacturing and designing. In various different types of micro machining, micro drilling is one of the tool based micro machining operation. Generally micro drilling is used to fabricate micro holes in micro products. Main emphasis is drilling speed (R.P.M) and the feed rate of the spindle. In this study, the cutting speed and feed rate will be taken as process parameters. We tried to increase the accuracy by giving feed to drill spindle through lead screw instead of direct feed. Here are some aspects which are considered in the design of universal micro radial drilling machine.

- by IJSTE - International Journal of Science Technology and Engineering
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- Micro, Universal, Torque, Rpm

Abstrak-Pemanfaatan sumber energi air terutama digunakan sebagai penyedia energi listrik melalui pembangkit listrik tenaga air maupun mikrohidro. Salah satu permasalahan adalah bagaimana memanfaatkan potensi energi aliran air yang relatif kecil. Maka dari itu guna memanfaatkan dan meningkatkan potensi energi aliran air yang relatif kecil diperlukan penelitian. Pemanfaatan energi air pada penelitian ini adalah pemanfaatan energi kinetik aliran air. Energi mekanik yang merupakan transformasi dari energi kinetik aliran air dimanfaatkan untuk menggerakkan turbin atau kincir. Turbin poros vertikal tipe Savonius ini cocok digunakan untuk memanfaatkan energi aliran air yang relatif kecil. Penelitian dengan judul "Rancang Bangun Turbin Air Sungai Poros Vertikal Tipe Savonius dengan Menggunakan Pemandu Araha Aliran" dilakukan dengan metode eksperimen, dimana hasil dari rancang bangun turbin akan dilakukan pengujian dan pengambilan data. Data pengujian yang diperoleh berdasarkan dari pengaruh variasi kecepatan aliran 0,30 ; 0,57 ; 0,85 dan 1,08 (m/detik) serta pengaruh dari pemandu arah aliran. Performansi diperoleh dari hasil pengujian dan pengukuran. Diperoleh Cp maksimum 0,13 pada TSR 1,53 dengan kecepatan aliran 0,57 (m/detik) serta pengaruh dari pemandu arah aliran. RPM maksimum diperoleh sebesar 162 dan daya keluaran maksimum generator sebesar 2311 (mW). Pengaruh pemandu arah aliran dapat meningkatkan performansi turbin Savonius diperoleh efisiensi sebesar 13,16%. Sehingga dapat disimpulkan bahwa dengan kecepatan aliran air yang sangat rendah turbin tipe Savonius dapat membangkitkan energi listrik.

- by Ridho Hantoro
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- Rpm

This study investigated differences in gluten aggregation time and gluten strength using the Hofmeister series in high shear-treated slurries. Two flours (15.1% and 10.6% protein) were evaluated by using a Gluten Peak Tester (GPT). Hofmeister anions including NaF, NaCl, NaBr, NaI, and NaSCN at concentrations ranging from 0.1 to 1.0 M and cations including KCl, NaCl, NH 4 Cl, MgCl 2 , and CaCl 2 at concentrations ranging from 0.0625 to 1.0 M were used. The instrument applies high shear to a flour/salt solution slurry and measures torque and aggregation time to form gluten. Aggregation time using the GPT followed the order of the Hofmeister series, with minor effects at salt concentration b 0.3 M and increasing differences at higher salt concentrations. Torque increased with increasing concentration. Creating models of the trends using second and third order equations demonstrated that gluten aggregation follows a distinct natural law in the slurries. The study confirmed the potential of the high shear based method to be used a research tool to investigate gluten aggregation properties and to potentially predict functionality in baked product systems.

- by Massimo Marcone
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- Chemical Engineering, Food, Time Use, Food Sciences

Part I of this Essay sets out why the legal framework in the EU amplifies what are, in reality, relatively small differences in thinking about resale price maintenance ("RPM"). This amplification is primarily due to the fact that the legal system asks economists, in the name of legal certainty, to draw a false dichotomy between those agreement and practices that are harmful and those that are beneficial. For practices like naked price-fixing, it is relatively easy for economists to agree on an answer. It is harder, however, for practices like RPM, which can give rise to serious anticompetitive harm, but can also prove to be indispensable for important and valuable benefits to consumers. Part II therefore provides a summary of the economic literature on RPM and emphasizes the need for further empirical research in this area. Within the current legal framework, there is not yet sufficient evidence to justify moving RPM out of the EU's "presumed illegality" or "object" box and into a case-by-case assessment of "effect" box. It is clear, however, that this approach will sometimes presume that some RPM arrangements are illegal when in fact they either do not restrict competition or, if they do, they are nevertheless justified by generating consumer benefits. Accordingly, we would have significant reservations about a legal framework that goes beyond "presumed illegality," for example making RPM de facto illegal or even per se illegal, as in the United States before Leegin. On the basis of these beliefs, Part III suggests several small steps that can be taken towards assessing RPM within a "presumed illegality" framework without sacrificing too much of the legal certainty that is realized under the current approach. First, we argue that it is important to ensure that any presumption of illegality is truly rebuttable, and provide some thoughts as to how this might work. This includes the requirement that the authority should set out at least one plausible "theory of harm" that is consistent with known facts. Second, we suggest that a series of screens might usefully be adopted for considering whether there is likely to be a credible theory of harm in any particular case of RPM, and for prioritizing cases on this basis. Third we recognize that a prioritization approach may not be as effective in a system such as the United States, where competition law is primarily enforced via cases brought by private litigants. There may, nevertheless, be some potential to use screens of this sort to help define a legal standard. Under this approach, failure of the screens would demonstrate that there is no credible theory of harm associated with a particular case of RPM and the presumption of illegality could be rebutted. This approach would be similar to the screens that are commonly applied in the EU in article 102 TFEU ("Treaty on the Functioning of the European Union") (article 82 EC ("Treaty Establishing the European Community")) abuse-of-dominance cases.

- by Emanuele Giovannetti and +1
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- Law, Competition Law, Competition Policy, European Union

Resumen: El presente estudio muestra las diferentes pruebas de laboratorio utilizadas para reconocer los mecanismos de daño de formación y enlazar el comportamiento de producción asociado con la arenisca Hollín de la Cuenca Oriente. Se... more

- by Revista Politécnica EPN
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- Fracture, XRD, Fracturas, Rpm

A valuable method for evaluating the functional effects of promising candidates in cardiac drug discovery is the analysis of electrophysiological characteristics. In vitro techniques facilitate the investigation of physiological parameters, including action potential generation, conduction, arrhythmia and QT duration, to chemical provocation and at the same time benefit from defined experimental conditions as well as enhanced accessibility. A widespread approach to studying the electrophysiological properties of developing and mature cellular networks in vitro is the multichannel recording of cardiac cells cultured as monolayers on microelectrode arrays. However, common two-dimensional monolayer cell cultures do not accurately reflect in vivo conditions. Cells within a tissue are organized into a complex three-dimensional pattern, and cellular interactions are not limited to a two-dimensional environment. Here, we report on a biosensor that combines the microelectrode array technique with cardiac threedimensional cellular networks. Fully dissociated primary cells from chicken embryonic hearts were re-aggregated into spheroids. We found that action potentials could be recorded with an excellent signalto-noise-ratio for up to several weeks. The administration of cardioactive drugs significantly altered the electrophysiological characteristics of the spheroids. Cellular responses were investigated along with the biosensor's potential as a tool for estimating the effectiveness and the risk of adverse reactions of drugs.

- by Paul G Layer
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- Materials Engineering, Analytical Chemistry, Tissue Engineering, BioMEMS
- by Herbert Hovenkamp
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- Agency, Rpm

Sedimentation field-flow fractionation (SdFFF) was applied to characterize particle size distributions of food materials. Two types of food particles were examined, including milk suspensions and flour samples. Milk eluted in the normal mode SdFFF, whereas the steric mode of retention was used for flour samples. Various types of milk being investigated were from cereal and cowÕs origins. The cereal milk samples included corn, jobÕs tear, rice, and soy milk, whereas the bovine milk included chocolate and fresh full-fat milk. Most samples exhibited monomodal size distributions, whereas corn milk displayed a slight deviation from monomodal characteristic. The mean particle sizes were detected to be approximately 0.4 lm for all cereal milk, except that they were approximately 0.5 lm for corn and all bovine milk. The application of SdFFF for micrometer size food particles was demonstrated for four types of flour samples, including corn, mung bean, rice, and tapioca flours. Significantly differences in the particle size characteristics of all flour samples were observed, by which corn, mung bean, rice, and tapioca yielded mean particle sizes of 16.7, 31.5, 13.5, and 19.9 lm, respectively. The ability of SdFFF for size separation of flours was confirmed by comparing the results obtained with those from scanning electron microscopy (SEM). Further, a new way to examine flour swelling was proposed. This study has demonstrated the potential value of SdFFF technique for food scientists.

To better understand the biosynthesis of Camptotheca acuminata alkaloids, the effect on camptothecin production of feeding with potential precursors of biosynthesis was studied (i.e., tryptamine and loganin combined, secologanin, and strictosidine). Two key enzymes in alkaloid biosynthesis [i.e., tryptophan decarboxylase (TDC; EC 4.1.1.28) and strictosidine synthase (STR; EC 4.3.3.2)] were also studied. The analyses were conducted using a C. acuminata CG1 cell line that does not produce alkaloids, which could be useful in better understanding the biosynthetic pathway and in identifying possible limiting factors. The activity of TDC was 5 pkat mg-1; the activity of STR was 1.1 pkat mg -1 . Feeding with strictosidine revealed that this precursor is easily biotransformed by two enzymes (i.e., a hydroxylase and a dehydrogenase) in hydroxystrictosidine and didehydrostrictosidine, but camptothecin was never detected. The indole pathway and the low level of STR activity could be limiting factors in the production of camptothecin in the cell line used.

- by A. Silvestrini and +2
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- Production, Plant Biology, Cell Culture, Plant Physiology
- by Krist Gernaey
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- Mechanical Engineering, Chemical Engineering, Design, Data Analysis

The paper sets out why we consider that the legal framework in the EU amplifies what are in reality relatively small differences in thinking around RPM. Primarily, this is because it asks economists, in the name of legal certainty, to draw a false dichotomy between agreements and practices which are harmful and those which are beneficial. We then provide a summary of the literature on RPM and, based on this thinking, set out a few small steps that might be taken towards a more nuanced approach to assessing RPM, within a 'presumed illegality' framework without sacrificing the beneficial legal certainty that the current approach brings.

- by Emanuele Giovannetti
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- Law, Competition Law, Competition Policy, European Union

Lingkungan industri kecil adalah baris terdepan dari kehidupan masyarakat Indonesia, salah satunya adalah industri kecil pengecoran yang menggunakan bahan baku aluminium bekas. Metode pengecoran yang sering digunakan dan paling sederhana adalah menggunakan metode pengecoran gravitasi. Metode pengecoran gravitasi seperti ini biasanya banyak memiliki kekurangan pada produk coran, yaitu banyaknya produk yang memiliki cacat. Cacat yang sering terjadi pada metode pengecoran gravitasi salah satunya adalah keropos (porositas), hal ini disebabkan karena selama proses pengecoran logam cair masuk kedalam rongga cetak dengan hanya memanfaatkan gaya gravitasi sehingga menyebabkan produk coran menjadi cacat. Cacat lainnya yang sering timbul diantaranya adalah cacat salah alir, rongga udara dan rongga penyusutan yang mana cacat coran tersebut akan Intisari Penelitian ini membahas tentang pembuatan komponen yang terbuat dari tuangan paduan aluminium dengan menggunakan proses penuangan sentrifugal sumbu vertical, cetakan diputar pada 1000 Rpm dengan 2 macam temperatur cetak dan 3 variasi komposisi Al-Ti-B sebagai inokulan. Produk tuangan selanjutnya akan diuji dan di analisa sifat fisik dan makanisnya dengan beberapa metoda pengujian. Untuk proses pengujian digunakan bentuk-bentuk benda uji standar yang sesuai untuk standar pengujian seperti untuk; uji kekerasan, uji tarik dan uji impak yang menggunakan Standar pengujian ASTM dan selanjutnya akan pada mesin uji mekanis. Dari pengujian sebelumnya dari pengamatan miko struktur diketahui bahwa ukuran butiran pada tuangan sentrifugal akan semakin halus ukuran butirannya pada sisi terluar.Penjelasan dari hasil pengamatan ini disebabkan karena adanya gaya sentrifugal (CF) selama proses penuangan kedalam cetakan. Logam cair akan ditekan oleh gaya sentrifugal sehingga menimbulkan tekanan pada setiap layer, hal ini juga menjelaskan bahwa produk yang dibuat dengan menggunakan metoda ini bebas cacat, sisi terluar dari produk sentrifugal akan memiliki nilai kekerasan yang tinggi dibandingkan dengan sisi tengah produk, sifat mekanisnya juga akan memiliki nilai yang tinggi pada tekanan terbesar gaya sentrifugal (sisi terluar) dibandingkan kebagian tengah. Temperatur cetakan akan berpengaruh pada nilai kekerasan produk dari metoda ini.

- by Rudi Xerehore
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- Rpm

El presente estudio tiene la finalidad de determinar
los niveles de opacidad con el uso de diésel fósil como
de biodiésel a base de higuerilla al 15 % (B15). Para
la determinación de la opacidad se utilizó un banco
de pruebas de motores diésel electrónico, se realizó
las mediciones de opacidad usando un opacímetro
debidamente calibrado. El opacímetro consta de una
sonda la cual se le instala en el extremo del tubo
de escape, captando los gases y arrojando valores
propios por cada prueba, considerando los tipos de
combustibles fósil o biocombustible y el régimen del
motor, sometiendo a varias revoluciones por minuto
que van de 1200 a 3000 por cada combustible. Al
concluir las pruebas el opacímetro permitió obtener
una opacidad de 11,1 % con diésel fósil y 0,386 con
biodiésel B15 obteniendo una reducción del 96 % de
opacidad, a la vez se obtuvo un promedio de opacidad
de las pruebas por cada tipo de combustible siendo
este valor el que se comparará con las normas nacionales
e internacionales concernientes a este estudio.
Con estos resultados se contribuye a la mejor conservación
del ambiente ya que se emana menor cantidad
de hollín, de igual manera se disminuye las enfermedades
respiratorias y de corazón de las personas
según la organización mundial de la salud.

- by Ingenius: Revista de Ciencia y Tecnología
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- Biodiesel, Rpm, Higuerilla

The efficiency of a waterwheel is a measure of its capacity to convert the kinetic energy of flowing water into mechanical energy. The rotation of a waterwheel is influenced by several parameters including blade shape, number of blades, nozzle angle, and rim diameter. This study focuses on finding the parameters that influence the rotations per minute (RPM) of the waterwheel. The research method involved analysis, modelling, and a validation step. The results show that the triangular blade was an improvement over previous research on waterwheels with propeller blades. Our experiments produced 5,73 higher efficiency than a vane having a nozzle angle θ of 20°.

- by Ardyono Priyadi
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- Renewable energy technology, Blade, Rpm, Electrical And Electronic Engineering

May AM, van Weert E, Korstjens I, Hoekstra-Weebers JE, van der Schans CP, Zonderland ML, Mesters I, van den Borne B, Ros WJ. Monitoring training progress during exercise training in cancer survivors: a submaximal exercise test as an alternative for a maximal exercise test?To examine the use of a submaximal exercise test in detecting change in fitness level after a physical training program, and to investigate the correlation of outcomes as measured submaximally or maximally.A prospective study in which exercise testing was performed before and after training intervention.Academic and general hospital and rehabilitation center.Cancer survivors (N=147) (all cancer types, medical treatment completed ≥3mo ago) attended a 12-week supervised exercise program.A 12-week training program including aerobic training, strength training, and group sport.Outcome measures were changes in peak oxygen uptake (Vo2peak) and peak power output (both determined during exhaustive exercise testing) and submaximal heart rate (determined during submaximal testing at a fixed workload).The Vo2peak and peak power output increased and the submaximal heart rate decreased significantly from baseline to postintervention (P<.001). Changes in submaximal heart rate were only weakly correlated with changes in Vo2peak and peak power output. Comparing the participants performing submaximal testing with a heart rate less than 140 beats per minute (bpm) versus the participants achieving a heart rate of 140bpm or higher showed that changes in submaximal heart rate in the group cycling with moderate to high intensity (ie, heart rate ≥140bpm) were clearly related to changes in VO2peak and peak power output.For the monitoring of training progress in daily clinical practice, changes in heart rate at a fixed submaximal workload that requires a heart rate greater than 140bpm may serve as an alternative to an exhaustive exercise test.

- by Ilse Mesters
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- Cancer, Treatment Outcome, Exercise therapy, Prospective studies

Coscinium fenestratum is a common medicinal plant widely used in the Indochina region, but scientific data on its safety is very limited. This study aimed to observe the effect of this plant on neurotoxicity and neurobehavior. Oral administration of plant alcoholic extract at dosages of 5, 10 and 20 mg/kg BW for 14 days increased the rats body weight and decreased the neuron density in the cerebral cortex, hippocampus and striatum. The plant extract significantly increased stereotyped behavior in licking but did not cause anxiolytic activity, anti-depression, sensory motor co-ordination impairment and ataxia. It is concluded that the plant possesses neurotoxicity and is able to induce neurobehavioral changes in rats. Therefore, the application of this plant as either drug or supplementary food should be reconsidered.

- by Nongnut Uabundit and +1
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- Animal Behavior, Traditional Medicine, Thailand, Medicinal Plants

In studies on the release of drugs, antioxidants, vitamins, etc., from submicrometric particles, the released portion cannot be separated from that which remains entrapped in the carrier using conventional filtration methods due to the membrane cut-off. Thus, other methods, for example, ultrafiltration-centrifugation or dialysis with dialysis bags, which enable this separation are used. However, as the substances vehiculated in colloidal aqueous solutions are usually poorly water soluble substances, it is not easy to obtain their intrinsic flux (J 0 ) value in aqueous solution. In this context, our objective was to develop a strategy to obtain the J 0 value of a poorly water soluble substance dialysate from an aqueous solution aiming to compare it with its apparent flux (J app ) from an aqueous colloidal system allowing the evaluation of the effect of nanoencapsulation on the release rate of a lipophilic substance. Different hydroethanolic solutions of a poorly water soluble substance (benzophenone-3 (BZ3)) were dialyzed against hydroethanolic media using dynamic dialysis with bags. The J app value of BZ3 in each system was plotted as a function of the proportion of organic solvent and the exponential mathematical Abbreviations: a, a constant which incorporates structural and geometric characteristics of the pharmaceutical form; A, the active substance percentage dialyzed at time t in burst release stage; B, the active substance percentage dialyzed at time t in continuous release stage; BZ3, benzophenone-3; BZ3-LNC, Benzophenone-3-loaded lipid-core polymeric nanocapsules; C, percentage of BZ3 dialyzed at time t; C0, the total content of active substance (in percentage); CCT, caprylic/capric triglyceride; d4.3, volumeweighted mean diameter; DLS, dynamic light scattering; GPC, gel permeation chromatography; h, hours; HPLC, high performance liquid chromatography; J, flux/flow values; J0, intrinsic flux/flow value; Japp, apparent flux/flow value; k, k1 and k2, kinetics rate constants; LNC, lipid-core polymeric nanocapsules; M∞, amount of active substance in L. A. Fiel et al. / Colloids and Surfaces A: Physicochem. Eng. Aspects 441 (2014) 716-724 717 equation of this relation was used to calculate the J 0 value of the substance in aqueous solution. BZ3loaded lipid-core nanocapsule suspensions (BZ3-LNC) were used as a model for colloidal nanocarriers. The J app value obtained for the release from the BZ3-LNC suspension was around 14-fold lower than the J 0 value, indicating that the encapsulation of BZ3 into the LNC system was able to slows its diffusion. The strategy developed allows the use of the J 0 values of poorly water soluble substances in aqueous solutions to verify whether the nanoencapsulation can prolong, for example, the substance delivery on the biological environment.

- by Adriana Pohlmann
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- Engineering, SEM, HPLC, Physical sciences

- by Emanuele Giovannetti
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- Law, Competition Law, Competition Policy, European Union

Johnston TE, Smith BT, Mulcahey MJ, Betz RR, Lauer RT. A randomized controlled trial on the effects of cycling with and without electrical stimulation on cardiorespiratory and vascular health in children with spinal cord injury. Arch Phys... more

- by Richard Lauer
- •
- Pediatrics, Skeletal muscle biology, Treatment Outcome, Adolescent

The antoxidative properties of water hyacinth leaves were investigated by evaluating the scavenging capacity of liquid extracts in a competitive protective process against oxygenated free radicals (OFRs) released via electrolysis in a phosphate buffer with a Pt electrode. Colorimetric measurements carried out at 515 nm, through a N,N-diethyl-1,4-phenylenediamine (DPD) assay, showed a decreased absorbance of the sample, as compared to the blank obtained by electrolysis of the buffer without plant extract, revealing, thereby, the presence of antioxidizing agents in the liquid extracts. The antioxidative activity was estimated in terms of equivalent-glutathione (EG, in nmoles equivalent-glutathione per gram of dry plant material selected (eg/gdp)), and compared to those of soya beans and garlic bulbs. The EG value increased with decreasing dilution factors, regardless to the plant type, suggesting a strong influence of the medium pH on the antioxidizing agent extraction yields. Various plant drying procedures, namely: sunlight exposure (at 25-30 • C), heating (40 and 60 • C) and freeze-drying (at -70 • C) were also examined. The highest EG (ca. 40 nmol eg/gdp) was observed for freeze-dried leave extract, while the lowest value was obtained upon heating at 60 • C (16-17 nmol eg/gdp), presumably due to a detrimental effect of increased temperature. The glutathione content in the plant extracts was further determined spectroscopically at 412 nm, through an enzymatic assay, using glutathione reductase. Small but interesting contents of glutathione (ca. 40 nmol eg/gdp) were found in the hyacinth leaves, making this plant to be regarded as an alternative and convenient low-cost raw material for antioxidizing agent recovery.

- by Abdelkrim Azzouz and +1
- •
- Free Radicals, Plant Biology, Plant Science, Free Radical

The results reported here for CBA/CaJ mice describe the effects of regular dosing with a common antiretroviral drug combination on outer hair cell (OHC) function using measures of 2f 1 -f 2 distortion product otoacoustic emissions (DPOAEs) and auditory brainstem responses (ABRs). Specifically, experimental mice were treated daily over a 3-mo period with the nucleoside reverse transcriptase inhibitors (NRTIs), zidovudine (ZDV) and lamivudine (3TC), dissolved in their drinking water, while their control counterparts received untreated water. DPOAE levels and ABR detection thresholds prior to and after 12 wk of NRTI treatment did not differ between experimental and control groups. To assess whether NRTI treatment potentiates the adverse effects of noise overexposure on OHC function, both experimental and control mice were exposed 1 wk later, while still on the drug regimen, to a 10-kHz octave-band noise (OBN) at 105 dB SPL for 1 h. A major outcome of the sound overexposure episode was that the NRTI-pretreated mice showed significantly greater permanent OBNinduced reductions in DPOAE levels at 2 wk postexposure than were observed for the untreated control animals. These findings support the notion that a synergistic relationship exists between certain NRTIs and intense sounds in that such preexposure drug treatments produced greater noiseinduced decreases in DPOAE activity than did noise exposure alone. This drug/noise interaction is consistent with the known harmful effects of NRTIs on cellular mitochondrial activity.

- by Devrim Bektaş
- •
- Treatment Outcome, Noise Induced Hearing Loss, DNA, Hearing

After injection of Sendai virus, a parainfluenza virus type I, mice generate cytotoxic lymphocytes which lyse specifically Sendai-virus-infected target cells in vitro. Their action is not inhibited by specific antibody in vitro. Killer cell activity appears 4 days after infection, reaches a maximum on the 7th day and disappears on the 14th to 16th day. Decrease of cytotoxic cell activity is correlated with an increase of haemagglutinating antibodies. The cytotoxic effector cell could be characterized as a thymus-derived cell, there is no specific activity in antibody-dependent cell-mediated cytolysis (ADCC). The degree of cytotoxic effector cell activity is only slightly influenced by the dose of injected infective virus. Using different syngeneic Sendai-virus-infected cells as targets for cell-mediated cytotoxicity, a tumor line was not lysed by cytotoxic lymphocytes in spite of viral surface antigens. Preliminary experiments were performed to demonstrate the H-2 gene restriction o...

- by Ulrich Koszinowski
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- Macrophages, LCM, Mice, ADCC

Dalam operasinya dilaut, suatu kapal harus memiliki kemampuan untuk mempertahankan kecepatan dinas (Vs) seperti yang direncanakan. Hal ini mempunyai arti bahwa, kapal haruslah mempunyai rancangan sistem propulsi yang dapat mengatasi keseluruhan gaya-gaya hambat yang terjadi agar memenuhi standar kecepatan dinasnya. Penelitian untuk meningkatkan daya dorong propeller dari tahun ketahun terus dilakukan dengan meningkatakan efisiensi propeller. Tapi dari sisi lain usaha untuk meneliti dimana konsentrasi tegangan yang diakibatkan daya dorong propeller masih kurang dilakukan Untuk Penelitian ini analisa yang dilakukan adalah untuk mengetahui distribusi tekanan pada propeller dan juga maximum stress yang terjadi pada propeller.

- by dian hafiz
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- Propeller, Kapal, Rpm, Cfd

Many extracts prepared from plants traditionally used for medicinal applications contain a variety of phytochemicals with antioxidant and antigenotoxic activity. In this work we measured the DNA protective effect of extracts of Ginkgo biloba leaves from oxidative stress using Saccharomyces cerevisiae as experimental model. The extract improved viability of yeast cells under oxidative stress imposed by hydrogen peroxide. In accordance with previous reports on antioxidant properties of G. biloba extracts, pre-incubation of yeast cells promoted a decrease in intracellular oxidation. We assessed DNA damage by our recently developed yeast comet assay protocol. Upon oxidative shock, DNA damage decreased in a dose-dependent manner in experiments of pre-incubation and simultaneous incubation with the extract, indicating a direct protective effect. In addition, the extract improved DNA repair rate following oxidative shock as measured by faster disappearance of comet tails. This suggests that the extract stimulates the DNA repair machinery in its DNA protective action in addition to directly protect DNA from oxidation. The observed DNA repair depends on the DNA repair machinery since no DNA repair was observed under restrictive conditions in a conditional mutant of the CDC9 gene (Accession No. Z74212), encoding the DNA ligase involved in the final step of both nucleotide and base excision repair.

- by Bjorn Johansson
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- Oxidative Stress, DNA damage, DNA repair, DNA

The user has requested enhancement of the downloaded file. All in-text references underlined in blue are added to the original document and are linked to publications on ResearchGate, letting you access and read them immediately. This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues.

- by Aidan Coffey
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- Genetics, RNA, Computational Biology, DNA

Background: Continuous-flow left ventricular assist devices (LVADs) have become part of the standard of care for the treatment of advanced heart failure. However, knowledge of normal values for transthoracic echocardiographic examination... more

- by Wes Colgan
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- Microbiology, Plant Biology, Fungi, Systematics
- by Emanuele Giovannetti
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- Law, Competition Law, Competition Policy, European Union

The shipping industry is striving to increase security for cargo containers without significantly impeding traffic. Three Science Applications International Corporation (SAIC) development programs are supporting this effort. SAIC's ICIS system combines SAIC's VACIS s g ray imaging, radiation scanning, OCR, elemental analysis and other technologies to scan containers for nuclear materials and other hazards in normal terminal traffic. SAIC's enhanced g ray detector improves VACIS image resolution by a factor of three. And SAIC's EmptyView software analyzes VACIS images to automatically verify empty containers.

- by rex richardson
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- Computer Science, Gamma, Clinical Sciences, Container

Objective: This study sought to evaluate the performance of microaxial ventricular assist devices for the purposes of supporting failing Fontan physiology by decreasing central venous pressure. Methods: Three Abiomed Impella pumps (Abiomed, Inc, Danvers, Mass) were evaluated in a mock circulatory system of the Fontan circuit. The local response of pressures and flows to pump function was assessed as a function of pump speed and pulmonary vascular resistance at a high baseline central venous pressure. For one device, subsequent modeling studies were conducted using a lumped parameter model of the single ventricle circuit. Results: The left ventricular devices (Impella 2.5, 5.0) were shown to be suboptimal as single device solutions for cavopulmonary support. The small area of these devices relative to vessel diameter led to significant flow recirculation without an obstructive separator in place. Furthermore, downstream pressure augmentation adversely affected the pressure in the superior vena cava. The use of 2 devices would be mandatory for successful support. The right-sided device (Impella RP), whose outflow was positioned in the left pulmonary artery, demonstrated decreased flow recirculation and did not impede superior caval venous flow. Although static pressure is still required to drive flow through the opposite lung, numeric modeling demonstrated the potential for modest but significant improvements in lowering the central venous pressure (2-8 mm Hg). Conclusions: Left-sided microaxial pumps are not well suited for cavopulmonary support because of severe flow recirculation and the need for multiple devices. The right-ventricular Impella device provides improved performance by directing flow into the pulmonary artery, resulting in modest decreases in central venous pressure.

- by Anne Valente
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- Computer Simulation, Hemodynamics, Clinical Sciences, prosthesis Design

- by Samuel Samuel
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- Engineering, Propeller, Kapal, Rpm

Astronauts experience weightlessness-induced bone loss due to an unbalanced process of bone remodeling that involves bone mesenchymal stem cells (bMSCs), as well as osteoblasts, osteocytes, and osteoclasts. The effects of microgravity on osteo-cells have been extensively studied, but it is only recently that consideration has been given to the role of bone MSCs. These live in adult bone marrow niches, are characterized by their self-renewal and multipotent differentiation capacities, and the published data indicate that they may lead to interesting returns in the biomedical/bioengineering fields. This review describes the published findings concerning bMSCs exposed to simulated/real microgravity, mainly concentrating on how mechanosignaling, mechanotransduction and oxygen influence their proliferation, senescence and differentiation. A comprehensive understanding of bMSC behavior in microgravity and their role in preventing bone loss will be essential for entering the future age of ...

- by Livia Barenghi
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- Spaceflight, Mesenchymal stem cells, Life, Microgravity

Anthocyanins are natural colorants which have raised a growing interest due to their extensive range of colours, innocuous and beneficial health effects. Despite the great potential of application that anthocyanins represent for food, pharmaceutical and cosmetic industries, their use has been limited because of their relative instability and low extraction percentages. Currently, most investigations on anthocyanins are focused on solving these problems, as well as their purification and identification.

- by Aracelli Pacheco
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- Chemistry, Organic Chemistry, Food Science, Nutrition

The effect of supplemental animal fat, or animal fat and rumen protected methionine, on lactating dairy ewes production was evaluated in the present study. Twelve dairy pregnant ewes of the Karagouniko breed, with two embryos, were allocated to three groups (treatments), in order to examine the effect of three diets: control (C), diet with animal fat at 7% of concentrates’ DM (F) and diet F plus 5 g rumen protected methionine (RPM) per kg of concentrate (F+m). The experiment started 2 weeks before lambing and continued for the 13 first weeks of lactation. During the experiment, dry matter intake (DMI), energy supply, daily milk yield and milk composition were determined. Prepartum, DMI and energy supply did not differ between treatments C and F+m. During the first 7 weeks of lactation (from lambing to weaning), the inclusion of fat in the diet increased DMI, energy supply (P<0.001), and the milk lactose content (P<0.05), but decreased the milk fat content (P<0.05). The inclusion of fat with RPM in the diet resulted in an increase (P<0.001) of DMI, milk yield and daily fat and protein yield, compared to treatments C and F. After weaning (8–13th week of lactation), significant differences were observed only in DMI and energy intake which increased (P<0.001) for treatments F and F+m. Milk fat content reduced (P<0.05) for treatments F and F+m, compared to control, but the mean daily milk fat and protein yield did not change significantly. For the first 13 weeks of lactation there was not treatment effect on milk protein profile, while the concentration of short chain fatty acids of milk fat was reduced (P<0.001) and that of short chain fatty acids increased (P<0.001) for treatments F and F+m, compared to treatment C. From the results of this experiment it is concluded that the inclusion of animal fat in sheep diets had no significant effect on ewes milk yield, while the use of rumen protected methionine, combined with animal fat, in diets of high producing ewes, at least at the first stage of lactation, increased significantly milk yield.

- by George Zervas
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- Animal Production, RUP, Yield, Milk Fat

The content of ␣-tocopherol and ␤-carotene in a grass crop consisting of timothy (Phleum pratense), meadow fescue (Festuca pratensis) and couch grass (Agropyron repens) was analyzed before and after conservation as silage and haylage during 11 months in either small square (bale size 80 cm × 48 cm × 36 cm) or round bales (diameter 57 cm, height 68 cm). The purpose of the experiment was to study the effect of degree of fermentation on ␣-tocopherol and ␤-carotene content by varying dry matter (DM) levels via different wilting times. Silage wilted for 4 h to 300 g DM/kg (SIL), haylage wilted for 24 h to 500 g DM/kg (HL1) and haylage wilted for 34 h to 600 g DM/kg (HL2), all harvested as long stemmed forage, were made from the same field. Tocopherols and carotenoids were analyzed by high performance liquid chromatography (HPLC). Generally HL1 contained less ␣tocopherol and ␤-carotene than SIL or HL2. There were no general effect of bale type on ␣-tocopherol and ␤-carotene content. SIL square bales and HL2 round and square bales contained 0.60 of initial ␣-tocopherol content and 0.86 of initial ␤-carotene content after ensiling, which were higher than SIL round bales and HL1 round and square bales containing 0.39 of initial ␣-tocopherol content and 0.33 Abbreviations: DM, dry matter; FM, fresh matter; SIL, silage; HL1, haylage with 500 g DM/kg; HL2, haylage with 600 g DM/kg; WSC, water soluble carbohydrates; CP, crude protein; NDF om , neutral detergent fibre without amylase and expressed exclusive of residual ash; VFA, volatile fatty acids; HPLC, high performance liquid 183 of initial ␤-carotene content. Thus, there was no clear relation between degree of fermentation and content of ␣-tocopherol or ␤-carotene. The strongest correlation was found between lactic acid and ␤-carotene (0.44) and lactic acid and ␣-tocopherol (0.41), indicating that a good conservation process (lactic acid fermentation) may favour the preservation of ␣-tocopherol and ␤-carotene in conserved forage.

- by james moller
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- Conservation, Animal Production, HPLC, Pigments

PNPase is a phosphate-dependent exonuclease of Escherichia coli required for growth in the cold. In this work we explored the effect of specific mutations in its two RNA binding domains KH and S1 on RNA binding, enzymatic activities, autoregulation and ability to grow at low temperature. We removed critical motifs that stabilize the hydrophobic core of each domain, as well as made a complete deletion of both (DeltaKHS1) that severely impaired PNPase binding to RNA. Nevertheless, a residual RNA binding activity, possibly imputable to catalytic binding, could be observed even in the DeltaKHS1 PNPase. These mutations also resulted in significant changes in the kinetic behavior of both phosphorolysis and polymerization activities of the enzyme, in particular for the double mutant Pnp-DeltaKHS1-H. Additionally, PNPases with mutations in these RNA binding domains did not autoregulate efficiently and were unable to complement the growth defect of a chromosomal Deltapnp mutation at 18 degrees C. Based on these results it appears that in E. coli the RNA binding domains of PNPase, in particular the KH domain, are vital at low temperature, when the stem-loop structures present in the target mRNAs are more stable and a machinery capable to degrade structured RNA may be essential.

- by Paolo Tortora
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- Genetics, Kinetics, Biological Sciences, Mutation
- by Lebogang Madubanya
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- Plant Biology, Biology, Ecology, Ex Situ Conservation

The growing demand for the antitumorous agent paclitaxel and the difficulty in increasing its production by genetic engineering has prompted a search for new sources of taxanes. It has been reported that taxanes can be extracted from the angiosperm Corylus avellana L. Our aim was to improve taxane production by scaling up the process from mL-level to benchtop bioreactors, optimizing culture conditions and comparing the effect of two elicitors, 1 μM coronatine (Cor) and 100 μM methyl jasmonate (MeJA). Orbitally shaken flask cultures achieved a maximum fresh cell weight of 11.54 gDCW/L under control conditions, and MeJA- and Cor-treatment produced a statistically significant reduction in growth to 4.28 gDCW/L and 5.69 gDCW/L, while increasing the taxane content 3- and 27-fold, respectively. The enhancing effect of these elicitors on taxane production, despite affecting growth, was confirmed in orbitally shaken TubeSpin Bioreactors 50, where the highest taxane content (8583.3 μg/L) was obtained when 1μM Cor was used and elicitation took place at a packed cell volume of 50%. Two benchtop stirred bioreactors, BIOSTAT B plus and UniVessel SU, were compared, the latter providing a higher biomass of C. avellana cell suspension cultures. Transferring the established optimum culture conditions for taxane production to the UniVessel SU resulted in a total taxane content of 6246.1 μg/L, a 10-fold increase compared with shake flask experiments.

- by Rosa Cusidó
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- Engineering, Chemistry, Technology, Biotechnology

Robust point matching (RPM) simultaneously estimates cor-respondences and non-rigid warps between unstructured point-sets. While RPM is robust to outliers in the target (fixed) point-set, its performance degrades when the template... more

- by Arunabha Roy
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- Mathematics, Computer Science, Cardiology, Surgery

We had demonstrated that membrane adsorption or penetration differentially modulated beta-Galactosidase (beta-Gal) activity against soluble substrates (Coll. and Surf., 24, 21, 2002). In a heterogeneous media, not only the enzyme but also the rest of the chemical species taking part in a chemical reaction would eventually interact with the available surfaces. The aim of the present work was to investigate if, in addition to changes in the intrinsic mechanism of the reaction at the lipid-water interface, the kinetics of enzyme-catalyzed reactions could be significantly affected by the partitioning of the substrate (ortho-nitro-phenyl galactopyranoside (ONPG)), the product (ortho-nitro-phenol (ONP)) and the enzyme (E. coli beta-Gal) towards the membrane. Multilamellar vesicles of sPC were used as model membranes. Membrane-water partition coefficients (Pm/w) were determined according to the theory and methodology developed previously (J. Neurosci. Meth. 36, 203, 1991). The values of Pm/w obtained (PONPG =0, PONP =50 and P beta-Gal = 118) were applied to a two-compartment model, which assumed a free access of the substrate to the enzyme and a nucleophile-like activatory effect exerted, within the membrane compartment, by the lipid-water interface. This model: (i) reproduced the lipid concentration-dependence we had observed previously in Vmax, (ii) predicted the values of k4 = 3.54 x 10(7) s-1 and the extinction coefficient of the aglycone in the membrane phase, 4012 M(-1) cm-1, with p &amp;amp;amp;amp;amp;lt; 0.0001 and p &amp;amp;amp;amp;amp;lt; 0.02, respectively, as well as for P beta-Gal =117 (which was poor (p=0.6716) but gave a numerical value within the same order of magnitude that the experimental value) and (iii) emphasized the importance of the more efficient reaction mechanism in the membrane phase compared with that in the aqueous phase (k4&amp;amp;amp;amp;amp;gt;k3).

- by Maria Perillo
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- Chemistry, Physical Chemistry, Catalysis, Kinetics

Possibly one of the most significant advantages that hydrogen may have as a fuel is its potential for increased second-law efficiency, due to fundamental differences in the mechanism of entropy generation during combustion with respect to the usual hydrocarbon-based fuels. A computational investigation of this effect is pursued for the case of mixtures of hydrogen and natural gas combusting in a diesel engine cylinder. The terms of the availability balance during engine operation are studied as a function of hydrogen content of the fuel and the operating parameters of the engine. Of particular importance is the confirmation of results provided in earlier work by the authors that combustion irreversibilities during hydrogen combustion can be drastically reduced. A single-zone computational model of the engine operation is used and the hypothesis of chemical equilibrium is invoked for combustion calculations. For the description of engine processes, such as fuel preparation and heat transfer, computational models established for hydrocarbon fuels are used so that a comparison is performed under the assumption that hydrogen combustion will be feasible in conditions that do not depart exceedingly from current engine configurations.

- by Dimitrios Kyritsis
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- Mechanical Engineering, Chemistry, Energy, Modeling

It has already been reported that in vivo muscle necrosis induced by various phenylenediamine derivatives correlated with their in vitro autoxidation rate [9]. Now in a more detailed investigation of the cytotoxic mechanism of a ring-methylated phenylenediamine known as tetramethylphenylenediamine or durenediamine (DD) towards isolated rat hepatocytes has been carried out. Cytotoxicity was preceded by ROS formation which was markedly increased by inactivating DT-diaphorase or catalase but were prevented by a subtoxic concentration of the mitochondrial respiratory inhibitor cyanide. This suggests that ROS generation could be attributed to a futile two-electron redox cycle involving oxidation of phenylenediamine to the corresponding diimine by the mitochondrial electron transfer chain and re-reduction by the DT-diaphorase. Endocytosis inhibitors, lysosomotropic agents or lysosomal protease inhibitors also prevented DD-induced cytotoxicity suggesting that DD-induced ROS caused lysosomal damage and protease activation in hepatocytes. Furthermore preincubation with deferoxamine (a ferric iron chelator) or addition of antioxidants, catalase or ROS scavengers (mannitol, tempol or dimethylsulfoxide) prevented DD cytotoxicity. These results suggest that H 2 O 2 reacts with lysosomal Fe 2+ to form "ROS" which causes lysosomal lipid peroxidation, membrane disruption, protease release and cell death.

- by Jalal Pourahmad
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- Cytotoxicity, Reactive Oxygen Species, Electron Transfer, ANOVA

- by Mauridhi Purnomo
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- Renewable energy technology, Blade, Rpm, Electrical And Electronic Engineering

Hampir di setiap rumah tangga dan industri menggunakan mesin listrik untuk mempermudah pekerjaan. Jenis mesin listrik yang umum digunakan adalah motor induksi. Hal ini disebabkan karena jenis motor induksi mempunyai kelebihan-kelebihan dibandingkan dengan jenis motor lainnya, antara lain karena konstruksinya sederhana dan harganya yang relative murah serta lebih ringan. Penelitian ini bertujuan membuat prototipe motor induksi 3 fasa dan mengetahui karakteristik hasil output RPM dari motor induksi tersebut. Desain prototipe motor induksi 3 fasa pada bagian statornya memanfaatkan bahan-bahan seperti koker sebanyak 6 buah dengan ukuran 6 cm x 4,2 cm, inti besi atau current berbentuk E sebanyak 168 buah dengan ukuran 6,6 cm x 4,4 cm dan current berbentuk I sebanyak 174 buah dengan ukuran 6,6 cm, untuk kumparannya menggunakan kawat email berdiameter 0,3 mm dengan jumlah 2200 lilitan. Pada bagian rotornya memanfaatkan kaleng bekas diberi belitan mengelilingi sisi-sisi kaleng. Pengujian motor induksi 3 fasa pada saat kaleng diberi belitan dan kaleng tanpa belitan. Pengamatan yang dilakukan adalah pengambilan data terkait tegangan input, arus dan RPM. Hasil penelitian menunjukkan bahwa pada saat tegangan input 50 volt rotor belum dapat berputar. Namun pada saat tegangan input 75 volt sampai 200 volt rotor dapat berputar secara perlahan sesuai tegangan yang dimasukkan, kecepatan putar rotor tersebut mencapai 290,3 RPM. Sedangkan pada saat rotor tanpa diberi belitan penelitian menunjukkan bahwa pada saat tegangan input 50 volt sampai 125 volt rotor belum dapat berputar, kemudian pada saat tegangan input 150 volt sampai 200 volt rotor dapat berputar namun sangat pelan hanya mencapai kecepatan putar maksimal 64,4 RPM. Hal ini disebabkan pada saat rotor tanpa diberi belitan, karena rotor tidak dapat menangkap medan magnet yang dikeluarkan oleh stator sehingga kumparan rotor tidak dapat mengalami gaya Lorentz yang menimbulkan torsi yang cenderung menggerakkan rotor sesuai arah pergerakan medan induksi stator.

- by Hasyim Asy'ari
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- Rpm