Muhammad Arshad | Bahria University, Islamabad-Pakistan (original) (raw)

Papers by Muhammad Arshad

A Radio telemetry study on Red Junglefowl (Gallus gallus spadiceus) was conducted in oil palm (El... more A Radio telemetry study on Red Junglefowl (Gallus gallus spadiceus) was conducted in oil palm (Elaeis guineensis) plantation at Sungai Sedu Estate, Selangor, Malaysia from October 1996 to July 1997. The main objective of the study was to examine the ranging behaviour of the species. Four Red Junglefowls (3 males and 1 female) were caught using decoy and leg trap method. They were then equipped with single stage 16 g transmitters and were radio-tracked using Mariner 57 receiver. The radiolocation was taken every 30 minutes by triangulation. The results show that the daily and monthly home range size of male was greater than that of a female. Similarly the home range size of a male without a female was greater than with a female. Environmental factors such as temperature, relative humidity, sunshine duration and cloud cover have no effect on the size of home range. The movement (distance travelled) contributes 49.1% of the variability on home range size. The total daily movement of ma...

OSA Advanced Photonics Congress (AP) 2020 (IPR, NP, NOMA, Networks, PVLED, PSC, SPPCom, SOF), 2020

Scientific Reports, 2021

We report on the observation of a new phenomenon occurring in a fiber ring laser. This phenomenon... more We report on the observation of a new phenomenon occurring in a fiber ring laser. This phenomenon is about the transition from an initially bidirectional emission of a reciprocal fiber ring laser to a unidirectional emission at a certain pump power threshold. In addition, the final direction is not predefined but appears to be randomly chosen every time the threshold is exceeded. Therefore, we term this new phenomenon direction instability. Furthermore, we provide a first discussion of how the instability threshold is influenced by the length and the loss of the cavity. We show that the threshold follows a power times length scaling, indicating a nonlinear origin.

OSA Advanced Photonics Congress 2021, 2021

Laser Physics Letters, 2019

We report on a new and simple approach for continuous wave supercontinuum generation in optical f... more We report on a new and simple approach for continuous wave supercontinuum generation in optical fibers. Our new approach uses the effect of stimulated Stokes Raman scattering in a low loss fiber ring laser. By continuously pumping this ring laser with up to 19 W optical power we excited up to six Stokes orders and covered a wavelength range of 500 nm. Due to the feedback mechanism of the ring layout additional nonlinear effects occurred next to the plain generation of individual Stokes peaks. Eventually, these effects broaden and merge the separated Stokes peaks and create a single, connected continuous supercontinuum. By using the effect of stimulated Stokes Raman scattering, we do not rely on anomalous dispersion and modulation instability as typically required for continuous wave supercontinuum generation.

European Thyroid Journal

Objective Post-surgical hypoparathyroidism (PoSH) usually settles within few months after thyroid... more Objective Post-surgical hypoparathyroidism (PoSH) usually settles within few months after thyroid surgery, but several patients require long-term supplementation with calcium/activated vitamin D. When PoSH persists beyond 6 months, it is considered ‘chronic’ or ‘permanent’, however, late recovery has been reported. The aim of this study was to determine the frequency of late recovery and explore factors predicting late recovery of parathyroid function. Methods Adult patients undergoing total/completion thyroidectomy between 2009 and 2018 were included in this retrospective cohort observational study. The records of patients with evidence of PoSH were reviewed to identify those with persisting PoSH at 6 months. Demographic, biochemical, surgical, pathological, and clinical follow-up data were collected and analysed. Results Out of 911 patients undergoing thyroidectomy, 270 were identified with PoSH. Of these, 192 were started on supplements and 138 (71.9%) recovered within 6 months. ...

IEEE Transactions on Network and Service Management

Much of the intrusion detection research focuses on signature (misuse) detection, where models ar... more Much of the intrusion detection research focuses on signature (misuse) detection, where models are built to recognize known attacks. However, signature detection, by its nature, cannot detect novel attacks. Anomaly detection focuses on modeling the normal behavior and identifying significant deviations, which could be novel attacks. In this paper we explore two machine learning methods that can construct anomaly detection models from past behavior. The first method is a rule learning algorithm that characterizes normal behavior in the absence of labeled attack data. The second method uses a clustering algorithm to identify outliers.

Endocrine Connections

Objective: To evaluate ‘real-world’ safety and efficacy of the European Society of Endocrinology ... more Objective: To evaluate ‘real-world’ safety and efficacy of the European Society of Endocrinology (ESE) guidelines for treatment of severe symptomatic hyponatraemia using hypertonic saline (HTS). Design: Retrospective, observational, cohort study, examining the use of HTS for severe symptomatic hyponatraemia at Sheffield Teaching Hospitals between 2017-2020. Methods: Patients were identified from pharmacy records and demographic, clinical, and treatment data extracted. Results: Out of 112 patients (Females: Males=61:51), the mean age ± SD was 66.3± 16.0 years and mean pre-treatment serum sodium ± SD was 113.8 ± 6.4 mmol/L. Overall, overcorrection rates at 24 and 48 hours (>10mmol/L and >18mmol/L) were 44.9% and 19.6%, respectively while 19.6% of patients were treated for overcorrection. Above-target rise in sodium (>5mmol/L) after first and second boluses was noted in 22.6% and 34.6% of patients. In-hospital and 12-month mortality was 7.1% and 18.7% respectively with no case...

Journal of Medicinal Plants Research, Jan 4, 2011

In the present studies foliar epidermal anatomy regarding 7 species belonging to 5 genera of trib... more In the present studies foliar epidermal anatomy regarding 7 species belonging to 5 genera of tribe Aveneae (Poaceae) was carried out. The studies revealed that different leaf anatomical characters, such as presence or absence of rounded short cells, length of long cells, size of stomatal complex and shape of silica bodies, are helpful in the identification of different species and genera within the tribe. Large cells with maximum length and largest stomatal complex are found in Avena sp. In genus Agrostis, Phalaris and Koeleria variations exist in the morphology of silica bodies. The studies revealed that diversity in different anatomical characters present within the species and genera is a valuable tool for the differentiation and correct identification of species in tribe Aveneae.

Journal of Medicinal Plants Research, May 18, 2011

Acetyl-cholinesterase (EC 3.1.1.7) comprise a family of enzymes which include serine hydrolases. ... more Acetyl-cholinesterase (EC 3.1.1.7) comprise a family of enzymes which include serine hydrolases. Acetyl-cholinesterase (AChE) catalyzes the hydrolysis of the neurotransmitter acetylcholine and termination of the nerve impulse in cholinergic synapses. AChE inhibitory activities were determined as given in Materials and Methods. Results show that the following plants have more than 50% inhibition of AChEase enzyme activity at 250 µg plant extract. Onosma bracteatum 61.12±4.28, Orchis mascula 59.80±2.2, Cymbopogon jawarancusa 70.6. AChE is used in the treatment of Alzheimer's disease and other related diseases. NADH oxidase (EC 1.6.99.3) catalyzes the two-electron reduction of oxygen to peroxide or the four-electron reduction of oxygen to water. 50% inhibition of NADH oxidase inhibitory activity was recorded at 250 µg plant extract of Alhagi. Maurorum 60.48±1.40 with Myristica fragrans 52.69±2.99, Nepeta hindostana 57.53±3.43, Pinus gerardiana 70.43±7.0. Other plant extracts showed <50% inhibitory activities against the two enzymes.

The 1st International Electronic Conference on Pharmaceutics, 2020

Low dissolution rates of poorly soluble drugs are the factor afflicting their bioavailability. Th... more Low dissolution rates of poorly soluble drugs are the factor afflicting their bioavailability. The aim of this study is to prepare a centrifugal spinning-based formulation of a poorly soluble drug, oxcarbazepine, for the improvement of dissolution rate and hence quick action. Sucrose-based microfibers of oxcarbazepine were prepared by a centrifugal melt spinning technique using a cotton candy machine. The prepared microfibers were characterized using Scanning electron microscopy (SEM), PXRD, Differential Scanning Calorimetry (DSC) and FTIR. The optimum formulation was molded into tablets and tested for in vitro drug release and in vivo pharmacokinetic studies using rabbits as test animals. The results indicated that the centrifugal spinning rapidly produced dissolving microfibers (diameter are <10 µm and dissolve in few seconds). In these fibers, ~20% oxcarbazepine was loaded, and both the yield and drug loading efficiency were improved by incorporating polyvinypyrolidine (PVP) in the formulations. The dissolution studies have revealed >90% of the drug was dissolved in just 2 min as compared with drug alone that shows only 15% dissolution at this time interval. XRD and DSC analyses have shown the amorphous state of the drug in the fibers while the FTIR analysis showed chemical stability of oxcarbazepine in the fibers. In vivo studies have revealed a 2 h reduction in tmax of drug in the rabbits treated with microfibers as compared with controlled group which was given pure oxcarbazepine. The study concludes the potential of the centrifugal spinning technique for the production of drug loaded fibers that can significantly enhance the dissolution rates of poorly soluble drugs and thus produce formulations for quick action of such drugs. Furthermore, the sucrose-based formulation can enhance the palatability with the intention of attracting pediatric patients.

In this paper, a simple active contour based visual tracking algorithm is presented for outdoor A... more In this paper, a simple active contour based visual tracking algorithm is presented for outdoor AGV application which is currently under development at the USM robotic research group (URRG) lab. The presented algorithm is computationally low cost and able to track road boundaries in an image sequence and can easily be implemented on available low cost hardware. The proposed algorithm used an active shape modeling using the B-spline deformable template and recursive curve fitting method to track the current orientation of the road.

Journal of the chemical society of pakistan, 2019

Two new monocyclic naphthene derivatives (1and 2) along with seven known compounds for the first ... more Two new monocyclic naphthene derivatives (1and 2) along with seven known compounds for the first time from the chloroform soluble fraction of the Tamarix indica. The structures of the isolated compounds were elucidated on the basis of modern sophisticated, EIMS, HREIMS, 1D and 2D-NMR spectroscopic techniques. The known compounds were recognized as 1-eicosanoyl (3), 6-heneicosanyl-1,2,4-trimethoxybenzene (4), 3-hydroxybenzoic acid (5), ethyl gallate (6) gallic acid (7), β-sitosterol (8) and methyl grevillate (9).

Pharmaceutical Sciences, 2020

Background: Hydrochlorothiazide HCl (HCTZ) is first line medication in the management of hyperten... more Background: Hydrochlorothiazide HCl (HCTZ) is first line medication in the management of hypertension, however its poor solubility and GI irritation warrants long term application. The aim of present study was to prepare hydrochlorothiazide HCl (HCTZ) loaded monodisperse microparticles of chitosan (CS) for sustained delivery. Methods: In the present study chitosan microparticle were prepared using ionic gelation method. The effect of input parameters such as concentration of chitosan and pH of CS solution on the mean particle size (PS), zeta potential (ZP), polydispersity index (PDI) and in-vitro drug release were investigated. In-vitro drug release from the microparticles was studied using Franz diffusion cell. Structural formation and surface morphology was investigated using FTIR and SEM, respectively. Results: PS of CS microparticles ranges from 0.878±0.066 to 1.963±0.011 µm, ZP between 33.43±0.80 mV to 53.6±2.06 mV, PDI values from 0.271±0.063 to 0.842±0.073. The optimized CSMP...

About these letters and their recipients No attempt has been made to alter the text of the letter... more About these letters and their recipients No attempt has been made to alter the text of the letters. Asad sent both typed and handwritten letters. The language and phrases used by Asad over the extended period of fifty years (1935-1986) during which these letters were written, provide important clues to his intellectual and personal developments. Until his arrival in the Indian Subcontinent in 1932, Asad had not written much in English. His articles for the German and Swiss newspapers were in German. He had learned conversational Arabic during his second trip to the Muslim lands (1924-1926), and seemed to have quickly learned to read scholarly texts while he was in Arabia. He provides no details of his teachers, but vaguely says he studied Sahih Bukhari in Madinah. (1) These letters reveal that once in India, Asad quickly picked up English usage spoken and written in the Indian Subcontinent at that time. His shorthand notations, the use of words peculiar to the Subcontinent (Begum sa...

Journal of environmental quality, 2005

Bacterial reduction of the Se oxyanions selenate [Se(VI)] and selenite [Se(IV)] to elemental sele... more Bacterial reduction of the Se oxyanions selenate [Se(VI)] and selenite [Se(IV)] to elemental selenium [Se0] is an important biological process in removing Se from drainage water. This study was conducted to characterize the molecular diversity of bacterial populations involved in Se reduction of drainage water amended with rice (Oryza sativa L.) straw and also to monitor the bacterial community shifts during the course of the study. Selenate was removed in the drainage water by the bacteria 5 to 6 d after addition of rice straw. Six Se(VI)- and 32 Se(IV)-reducing bacteria were isolated from rice straw containing sterilized drainage water. Three Se(VI)- and two Se(IV)-reducing bacteria were also isolated from the drainage water. Identification of Se(VI)- and Se(IV)-reducing bacteria by 16S rDNA sequence analysis showed a broad phylogenetic diversity in Se-reducing assemblages. Three major phyla (Proteobacteria, Actinobacteria, and Firmicutes) of bacterial domain with numerous classes...

Polymers, 2021

In this paper, the interaction of imipramine hydrochloride (IMP, antidepressant drug) and a non-i... more In this paper, the interaction of imipramine hydrochloride (IMP, antidepressant drug) and a non-ionic surfactant Triton X-100 (TX-100) mixture in five different ratios through the tensiometric method in different solvents (aqueous/0.050 mol·kg−1 aqueous NaCl/0.250 mol·kg−1 aqueous urea (U)) were examined thoroughly at a temperature of 298 K. UV–Visible studies in an aqueous system of IMP + TX-100 mixtures were also investigated and discussed in detail. The pure (IMP and TX-100) along with the mixtures’ critical micelle concentration (cmc) were assessed by a tensiometric technique. The obtained deviation of the mixtures’ cmc values from their ideal values revealed the nonideal behavior of IMP + TX-100 mixtures amongst IMP and TX-100. Compared to aqueous systems, in the presence of aqueous NaCl, several changes in micelles/mixed micelles occurred, and hence a synergism/attractive interaction amongst components was found increased while in the existence of U, the synergism/attractive i...

Pharmaceutics, 2020

SARS-CoV-2 has affected people from all age groups, races and ethnicities. Given that many infect... more SARS-CoV-2 has affected people from all age groups, races and ethnicities. Given that many infected individuals are asymptomatic, they transmit the disease to others unknowingly, which has resulted in the spread of infection at an alarming rate. This review aims to provide an overview of the pathophysiology, preventive measures to reduce the disease spread, therapies currently in use, an update on vaccine development and opportunities for vaccine delivery. The World Health Organization has advised several precautions including social distancing, hand washing and the use of PPE including gloves and face masks for minimizing the spread of SARS-CoV-2 infection. At present, several antiviral therapies previously approved for other infections are being repositioned to study their efficacy against SARS-CoV-2. In addition, some medicines (i.e., remdesivir, chloroquine, hydroxychloroquine) have received emergency use authorisation from the FDA. Plasma therapy has also been authorised for em...

The Professional Medical Journal, 2008

Bilateral synchronous renal cell Carcinomas occur in approximately 1-3% of all patients with RCC.... more Bilateral synchronous renal cell Carcinomas occur in approximately 1-3% of all patients with RCC.Ultrasound and contrast-enhanced CT scan are the most useful tests for diagnosing and staging. US has an advantageover CT in determination of nature of the lesion (solid/cystic). CT is more sensitive in evaluation of lesion size anddetection of calcification and necrosis. CT also has an advantage over US in evaluation of perinephric extension,adjacent organ infiltration and regional lymphadenopathy. Both US and CT are equally sensitive in detection of IVCthrombus.

Pituitary, 2021

Purpose There is no consensus on quality of life (QOL) in patients with acromegaly requiring medi... more Purpose There is no consensus on quality of life (QOL) in patients with acromegaly requiring medical treatment after surgery compared with those achieving remission by surgery alone. Methods QuaLAT is a cross-sectional study comparing QOL in surgery-only treated acromegaly patients versus those requiring medical treatment post-surgery. Patients attending clinics were identified and divided into—Group 1: patients who had surgery only and were in biochemical remission, Group 2: all patients on medical treatment post-surgery, Group 3: patients from Group 2 with biochemical control. Participants were asked to fill three questionnaires; Acromegaly Quality of Life Questionnaire (ACROQOL), 36-Item Short Form Survey (SF36), and Fatigue Severity Scale (FSS). Results There were 32 patients in Group 1 and 25 in Group 2. There was no difference in QOL scores between groups 1 and 2, as measured by ACROQOL (mean difference [MD] = − 2.5, 95% CI − 16.6 to 11.6; p = 0.72), SF36v2 [Physical component...