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Papers by Fernando Santos

Social Semiotics, 2013

ABSTRACT

Natural Resources, 2014

Biorefinery is a new term to designate two main subjects, bioproducts and bioenergy, which play i... more Biorefinery is a new term to designate two main subjects, bioproducts and bioenergy, which play important roles towards a more bio-based society. This paper reviews the current biorefineries model as well as its future importance focusing on pulp mill opportunities. There are currently several different levels of integration in biorefineries which add to their sustainability, both economically and environmentally. Enzymatic pretreatment for biomass deconstruction aiming to release the polysaccharides is a key technology in the future biorefineries and it is currently the subject of intensive research. et al.

Occupational Safety and Hygiene, 2013

Textbook of Clinical Pediatrics, 2012

Encyclopedia of Metagenomics, 2015

Encyclopedia of Metagenomics, 2013

To demonstrate an objective, quantitative, and sensitive method of mapping retinal fluorescein le... more To demonstrate an objective, quantitative, and sensitive method of mapping retinal fluorescein leakage into the vitreous while simultaneously imaging the retina. A prototype Zeiss confocal scanning laser ophthalmoscope was modified to obtain fluorometric measurements from 18 optical planes across the retina and cortical vitreous, separated from each other by 150 microm, and parallel to the retinal surface. After intravenous administration of fluorescein, an axial graphic of equivalent fluorescein concentration in the vitreous may be obtained from any region of interest. After correcting for fluorescence levels in the retina and choroid and plasma levels of free fluorescein, permeability values of the blood-retinal barrier to fluorescein were obtained from 1512 regions measuring 75 x 75 microm, from a total 3150 x 2700-microm area of the fundus, generating a detailed map of retinal fluorescein leakage. The method was assessed in vitro and in 7 healthy subjects who underwent scans during separate visits. Depth resolution and influence of chorioretinal fluorescence were further tested in 2 patients with multiple drusen and in 2 eyes after vitrectomy. Fourteen eyes from 7 patients with diabetes and nonproliferative retinopathy were also examined. Lateral resolution was tested in 3 diabetic eyes that underwent focal photocoagulation. Four eyes from 2 patients with diabetes and minimal retinopathy were examined at 3-month intervals. All eyes examined had less than 2 diopters of astigmatism. Characteristics of the modified confocal scanning laser fluorometer included a lower limit of detection equal to 0.40 Eq ng/mL and depth precision of +/-15 microm. Values for the blood-retinal barrier permeability index in healthy subjects, measured 30 minutes after a single intravenous pulse of fluorescein (14 mg/kg), ranged from 1.3 +/- 0.4 x 10(-6) cm/s over the foveal avascular zone to 2.2 +/- 0.6 x 10(-6) cm/s over vessels in the retina. Diabetic eyes with retinopathy showed higher values, ranging from 1.4 to 15.0 x 10(-6) cm/s. Vitrectomized eyes and eyes with multiple drusen showed the validity of the correction algorithm demonstrating that measurements of fluorescence in the vitreous are not influenced by the chorioretinal fluorescence level. Argon laser photocoagulation burns placed in the diabetic retina demonstrated a lateral resolution on the order of 75 to 100 microm. Intravisit and intervisit reproducibility was +/-10.2% and +/-13%, respectively. This new method measures localized alterations of the blood-retinal barrier and allows for direct correlation with retinal anatomy. Its most interesting feature is the ability to map retinal fluorescein leakage while simultaneously imaging the retina. This capability is expected to improve our understanding and management of retinal disease.

Pediatric Nephrology, 1998

Extremophiles, 2005

Salinibacter ruber is the first extremely halophilic member of the Bacteria domain of proven envi... more Salinibacter ruber is the first extremely halophilic member of the Bacteria domain of proven environmental relevance in hypersaline brines at or approaching NaCl saturation, that has been brought to pure culture. A collection of 17 strains isolated from five different geographical locations (Mallorca, Alicante, Ebro Delta, Canary Islands, and Peruvian Andes) were studied following the currently accepted taxonomic approach. Additionally, random amplification of genomic DNA led to the phenetic analysis of the intraspecific diversity. Altogether the taxonomic study indicated that S. ruber remained highly homogeneous beyond any geographical barrier. However, genomic fingerprints indicated that populations from different isolation sites could still be discriminated.

Applied and Environmental Microbiology, 2006

Maras salterns are located 3,380 m above sea level in the Peruvian Andes. These salterns consist ... more Maras salterns are located 3,380 m above sea level in the Peruvian Andes. These salterns consist of more than 3,000 little ponds which are not interconnected and act as crystallizers where salt precipitates. These ponds are fed by hypersaline spring water rich in sodium and chloride. The microbiota inhabiting these salterns was examined by fluorescence in situ hybridization (FISH), 16S rRNA gene clone library analysis, and cultivation techniques. The total counts per milliliter in the ponds were around 2 ؋ 10 6 to 3 ؋ 10 6 cells/ml, while the spring water contained less than 100 cells/ml and did not yield any detectable FISH signal. The microbiota inhabiting the ponds was dominated (80 to 86% of the total counts) by Archaea, while Bacteria accounted for 10 to 13% of the 4,6-diamidino-2-phenylindole (DAPI) counts. A total of 239 16S rRNA gene clones were analyzed (132 Archaea clones and 107 Bacteria clones). According to the clone libraries, the archaeal assemblage was dominated by microorganisms related to the cosmopolitan square archaeon "Haloquadra walsbyi," although a substantial number of the sequences in the libraries (31% of the 16S rRNA gene archaeal clones) were related to Halobacterium sp., which is not normally found in clone libraries from solar salterns. All the bacterial clones were closely related to each other and to the ␥-proteobacterium "Pseudomonas halophila" DSM 3050. FISH analysis with a probe specific for this bacterial assemblage revealed that it accounted for 69 to 76% of the total bacterial counts detected with a Bacteria-specific probe. When pond water was used to inoculate solid media containing 25% total salts, both extremely halophilic Archaea and Bacteria were isolated. Archaeal isolates were not related to the isolates in clone libraries, although several bacterial isolates were very closely related to the "P. halophila" cluster found in the libraries. As observed for other hypersaline environments, extremely halophilic bacteria that had ecological relevance seemed to be easier to culture than their archaeal counterparts.

Microbial Ecology, 2006

Biological soil crusts are very sensitive to human-induced disturbances and are in a degraded sta... more Biological soil crusts are very sensitive to human-induced disturbances and are in a degraded state in many areas throughout their range. Given their importance in the functioning of arid and semiarid ecosystems, restoring these crusts may contribute to the recovery of ecosystem functionality in degraded areas. We conducted a factorial microcosm experiment to evaluate the effects of inoculation type (discrete fragments vs slurry), fertilization (control vs addition of composted sewage sludge), and watering frequency (two vs five times per week) on the cyanobacterial composition, nitrogen fixation, chlorophyll content, and net CO 2 exchange rate of biological soil crusts inoculated on a semiarid degraded soil from SE Spain. Six months after the inoculation, the highest rates of nitrogen fixation and chlorophyll a content were found when the biological crusts were inoculated as slurry, composted sewage sludge was added, and the microcosms were watered five times per week. Net CO 2 exchange rate increased when biological crusts were inoculated as slurry and the microcosms were watered five times per week. Denaturing gradient gel electrophoresis fingerprints and phylogenetic analyses indicated that most of the cyanobacterial species already present in the inoculated crust had the capability to spread and colonize the surface of the surrounding soil. These analyses showed that cyanobacterial communities were less diverse when the microcosms were watered five times per week, and that watering frequency (followed in im-portance by the addition of composted sewage sludge and inoculation type) was the treatment that most strongly influenced their composition. Our results suggest that the inoculation of biological soil crusts in the form of slurry combined with the addition of composted sewage sludge could be a suitable technique to accelerate the recovery of the composition and functioning of biological soil crusts in drylands.

Journal of Automated Methods & Management in Chemistry, 1999

A computer-actuated switch was built to control, simultaneously, two automatic titration assembli... more A computer-actuated switch was built to control, simultaneously, two automatic titration assemblies each consisting of an electrode pair and a burette, and using only one measuring device. This switch is modular, simple and versatile allowing easy adaptation and expansion; apart from its application in multiple-titration systems, this device can also be used for standard addition analysis and multi-component analysis using ion-selective electrodes (ISE).

Fertility and Sterility, 2008

To report a case where intra-amniotic injection of methotrexate (MTX) was used to terminate a cer... more To report a case where intra-amniotic injection of methotrexate (MTX) was used to terminate a cervical ectopic pregnancy that was resistant to IM MTX treatment.Case report.A 31-year-old woman, gravida 2, para 1, presented with painless vaginal bleeding. An early cervical pregnancy was diagnosed by transvaginal ultrasound.Intramuscular MTX therapy was started without success, and an intra-amniotic injection of MTX under ultrasonographic guidance was performed.Pregnancy termination.Pregnancy termination was successful, without complications or side effects.Local installation of MTX appears to be an effective and safe method; however, choice depends on gestational age, desire to preserve fertility, and, most of all, hemodynamic stability.

European Journal of Sport Science, 2008

Abstract It has been suggested that a greater number of injuries during the last third of practic... more Abstract It has been suggested that a greater number of injuries during the last third of practice sessions or matches could be related to alteration of lower limb neuromuscular control due to neuromuscular fatigue. This fatigue-related effect can be mediated by changes in joint ...