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1.
Am J Hum Biol ; 32(2): e23323, 2020 03.
Article in English | MEDLINE | ID: mdl-31506993

ABSTRACT

OBJECTIVES: The diagnosis and treatment of obesity are usually based on traditional anthropometric variables including weight, height, and several body perimeters. Here we present a three-dimensional (3D) image-based computational approach aimed to capture the distribution of abdominal adipose tissue as an aspect of shape rather than a relationship among classical anthropometric measures. METHODS: A morphometric approach based on landmarks and semilandmarks placed upon the 3D torso surface was performed in order to quantify abdominal adiposity shape variation and its relation to classical indices. Specifically, we analyzed sets of body cross-sectional circumferences, collectively defining each, along with anthropometric data taken on 112 volunteers. Principal Component Analysis (PCA) was performed on 250 circumferences located along the abdominal region of each volunteer. An analysis of covariance model was used to compare shape variables (PCs) against anthropometric data (weight, height, and waist and hip circumferences). RESULTS: The observed shape patterns were mainly related to nutritional status, followed by sexual dimorphism. PC1 (12.5%) and PC2 (7.5%) represented 20% of the total variation. In PCAs calculated independently by sex, linear regression analyses provide statistically significant associations between PC1 and the three classical indexes: body mass index, waist-to-height ratio, and waist-hip ratio. CONCLUSION: Shape indicators predict well the behavior of classical markers, but also evaluate 3D and geometric features with more accuracy as related to the body shape under study. This approach also facilitates diagnosis and follow-up of therapies by using accessible 3D technology.


Subject(s)
Adiposity , Body Size , Overweight/diagnosis , Abdominal Fat/physiology , Adult , Argentina , Female , Humans , Imaging, Three-Dimensional , Male , Middle Aged , Obesity/diagnosis , Young Adult
2.
Biomacromolecules ; 18(5): 1544-1555, 2017 May 08.
Article in English | MEDLINE | ID: mdl-28421746

ABSTRACT

The healing of chronic wounds requires intensive medical intervention at huge healthcare costs. Dressing materials should consider the multifactorial nature of these wounds comprising deleterious proteolytic and oxidative enzymes and high bacterial load. In this work, multifunctional hydrogels for chronic wound application were produced by enzymatic cross-linking of thiolated chitosan and gallic acid. The hydrogels combine several beneficial to wound healing properties, controlling the matrix metalloproteinases (MMPs) and myeloperoxidase (MPO) activities, oxidative stress, and bacterial contamination. In vitro studies revealed above 90% antioxidant activity, and MPO and collagenase inhibition by up to 98 and 23%, respectively. Ex vivo studies with venous leg ulcer exudates confirmed the inhibitory capacity of the dressings against MPO and MMPs. Additionally, the hydrogels reduced the population of the most frequently encountered in nonhealing wounds bacterial strains. The stable at physiological conditions and resistant to lysozyme degradation hydrogels showed high biocompatibility with human skin fibroblasts.


Subject(s)
Bandages , Chitosan/analogs & derivatives , Hydrogels/chemistry , Wound Healing , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Biocatalysis , Cells, Cultured , Cross-Linking Reagents/chemistry , Fibroblasts/drug effects , Fibroblasts/metabolism , Gallic Acid/analogs & derivatives , Humans , Hydrogels/chemical synthesis , Hydrogels/pharmacology , Hydrogels/therapeutic use , Matrix Metalloproteinases/metabolism , Oxidative Stress , Peroxidase/metabolism , Sulfhydryl Compounds/chemistry
3.
Viruses ; 15(12)2023 11 24.
Article in English | MEDLINE | ID: mdl-38140549

ABSTRACT

Classical swine fever (CSF) is a highly contagious transboundary viral disease of domestic and wild pigs. Despite mass vaccination and continuous eradication programs, CSF remains endemic in Asia, some countries in Europe, the Caribbean and South America. Since June 2013, Northern Colombia has reported 137 CSF outbreaks, mostly in backyard production systems with low vaccination coverage. The purpose of this study was to characterize the virus responsible for the outbreak. Phylogenetic analysis based on the full-length E2 sequence shows that the virus is closely related to CSF virus (CSFV) genotype 2.6 strains circulating in Southeast Asia. The pathotyping experiment suggests that the virus responsible is a moderately virulent strain. The 190 nucleotide stretch of the E2 hypervariable region of these isolates also shows high similarity to the CSFV isolates from Colombia in 2005 and 2006, suggesting a common origin for the CSF outbreaks caused by genotype 2.6 strains. The emergence of genotype 2.6 in Colombia suggests a potential transboundary spread of CSFV from Asia to the Americas, complicating the ongoing CSF eradication efforts in the Americas, and emphasizes the need for continuous surveillance in the region.


Subject(s)
Classical Swine Fever Virus , Classical Swine Fever , Viral Vaccines , Swine , Animals , Colombia/epidemiology , Phylogeny , Sus scrofa , Disease Outbreaks , Genotype
5.
Polymers (Basel) ; 15(1)2022 Dec 27.
Article in English | MEDLINE | ID: mdl-36616455

ABSTRACT

Poly(lactic acid) (PLA) and biosourced polyamide (PA) bioblends, with a variable PA weight content of 10-50%, were manufactured by melt blending in order to improve the behavior of PLA against thermal degradation. The effect of reactive extrusion on the thermal performance of PLA within bioblends was analyzed. The reactive extrusion was made by means of the addition of a styrene-acrylic multi-functional-epoxide oligomeric reactive agent (SAmfE), with the commercial name of Joncryl. Four parameters were considered in order to study the thermal behavior of bioblends against thermal decomposition: the onset decomposition temperature, the shape and temperature interval of the thermal decomposition patterns, the activation energy of the thermal decomposition, and the evidence leading to the most probable mechanism. The latter was determined by means of three evidence: standardized conversion functions, y(α) master plots, and integral mean error. It was shown that reactive extrusion of PLA as well as PA incorporation to the polymer matrix of PLA were responsible for an increase in the onset decomposition temperature of 10.4 °C. The general analytical equation (GAE) was used to evaluate the kinetic parameters of the thermal degradation of PLA within bioblends for various reaction mechanisms. It was shown that the random scission of macromolecular chains is the best mechanism for both untreated and treated PLA by means of reactive extrusion. It was shown that reactive extrusion together with higher content of PA resulted in an increased protective effect against the thermal degradation of PLA as demonstrated by an increase in activation energy of 60 kJ/mol. It was found that there is a relationship between the increase in activation energy and the increase in the onset decomposition temperature when using reactive extrusion. The improvement of the thermal stability of bioblends by means of reactive extrusion was explained by an increase in the complex viscosity from 980 to 2000 Pa·s at 0.06 rad/s and from 250 to 300 Pa·s at 630 rad/s for bioblend containing 30% of PLAREX and by a finer dispersion of PA within the PLAREX matrix. Results from DSC were not conclusive regarding the compatibility between both phases.

6.
Polymers (Basel) ; 14(21)2022 Oct 31.
Article in English | MEDLINE | ID: mdl-36365630

ABSTRACT

The use of recycled opaque PET (r-O-PET, with TiO2) as a reinforcement for the recycled polypropylene matrix (r-PP) was evaluated through the life cycle assessment according to different scenarios corresponding to two different recycled blends and considered two virgin raw plastic material as reference materials when comparing the environmental performance of the proposed treatments. The results indicate that the environmental performance was quite different for each blend, since the additional extrusion process required in scenario 2 (blend with TiO2) causes all impact categories analysed to report higher values when compared with scenario 1 (blend without TiO2). The stage that contributes the most corresponds to the different extrusion processes included in both recycling blends, representing at least 80% of the total for global warming. Compared with virgin raw materials, the blend with TiO2 showed better performance in all the impact categories analysed in comparison with virgin PA66, while the blend without TiO2 showed the opposite trend when compared to PP. Furthermore, the fact that the upcycling treatment was carried out on a pilot scale provides room for improvement when implemented on a full scale. It is worth noting the high energy consumption of the treatment processes and their associated cost, in addition to the market cost of virgin raw materials, however, when considering the environmental cost of raw materials, it is observed that when substituting virgin materials PP and PA66 for the blends evaluated in this study results in a reduction of the environmental price of up to 2.5 times.

7.
Science ; 376(6598): 1215-1219, 2022 06 10.
Article in English | MEDLINE | ID: mdl-35679394

ABSTRACT

Early naturalists suggested that predation intensity increases toward the tropics, affecting fundamental ecological and evolutionary processes by latitude, but empirical support is still limited. Several studies have measured consumption rates across latitude at large scales, with variable results. Moreover, how predation affects prey community composition at such geographic scales remains unknown. Using standardized experiments that spanned 115° of latitude, at 36 nearshore sites along both coasts of the Americas, we found that marine predators have both higher consumption rates and consistently stronger impacts on biomass and species composition of marine invertebrate communities in warmer tropical waters, likely owing to fish predators. Our results provide robust support for a temperature-dependent gradient in interaction strength and have potential implications for how marine ecosystems will respond to ocean warming.


Subject(s)
Aquatic Organisms , Biomass , Fishes , Hot Temperature , Invertebrates , Predatory Behavior , Animals , Global Warming , Oceans and Seas
8.
Polymers (Basel) ; 13(22)2021 Nov 19.
Article in English | MEDLINE | ID: mdl-34833295

ABSTRACT

Poly(lactic acid) (PLA) and biosourced polyamide (PA) bioblends, with a variable PA weight content of 10-50%, were prepared by melt blending in order to overcome the high brittleness of PLA. During processing, the properties of the melt were stabilized and enhanced by the addition of a styrene-acrylic multi-functional-epoxide oligomeric reactive agent (SAmfE). The general analytical equation (GAE) was used to evaluate the kinetic parameters of the thermal degradation of PLA within bioblends. Various empirical and theoretical solid-state mechanisms were tested to find the best kinetic model. In order to study the effect of PA on the PLA matrix, only the first stage of the thermal degradation was taken into consideration in the kinetic analysis (α < 0.4). On the other hand, standardized conversion functions were evaluated. Given that it is not easy to visualize the best accordance between experimental and theoretical values of standardized conversion functions, an index, based on the integral mean error, was evaluated to quantitatively support our findings relative to the best reaction mechanism. It was demonstrated that the most probable mechanism for the thermal degradation of PLA is the random scission of macromolecular chains. Moreover, y(α) master plots, which are independent of activation energy values, were used to confirm that the selected reaction mechanism was the most adequate. Activation energy values were calculated as a function of PA content. Moreover, the onset thermal stability of PLA was also determined.

9.
Polymers (Basel) ; 13(2)2021 Jan 19.
Article in English | MEDLINE | ID: mdl-33478158

ABSTRACT

This work provides an experimental analysis regarding the fracture behavior of recycled opaque PET (rPET-O) containing titanium dioxide (TiO2) under plane stress conditions. For this purpose, a commercially post-consumer transparent colored/opaque PET flakes mix was processed using a semi-industrial extrusion calendering process. The manufactured rPET-O sheets had a TiO2 content of 1.45 wt.%. The mechanical and fracture properties of unaged and physically aged (1 year) samples were determined through uniaxial tensile experiments and the Essential Work of Fracture (EWF) methodology, respectively, and were compared to those of recycled transparent PET (rPET-T). Under tensile loading, independently of the aging time, rPET-O samples exhibited similar mechanical behavior as rPET-T up to the yield point. The main differences remained in the post-yielding region. The presence of TiO2 particles allowed reducing the strain energy density up to neck formation in aged samples. Regarding the EWF analysis, it is argued that the energy consumed up to the onset of crack propagation (we) for rPET-T was mainly dependent of the molecular mobility. That is, the we value decreased by 26% when rPET-T was physically aged. Interestingly, we values remained independent of the aging time for rPET-O. In fact, it was highlighted that before crack propagation, the EWF response was principally governed by matrix cavitation ahead of the crack tip, which allowed a significant release of the triaxial stress state independently of the molecular mobility. This property enabled rPET-O to exhibit a resistance to crack initiation 17% higher as compared to rPET-T when the material was physically aged. Finally, independently of the aging time, rPET-O exhibited a resistance to crack growth approximately 21% larger than rPET-T due to matrix fibrillation in large scale deformation.

10.
Polymers (Basel) ; 13(14)2021 Jul 19.
Article in English | MEDLINE | ID: mdl-34301118

ABSTRACT

This work presents the experimental results of the mechanical and fracture behaviour of three polymeric blends prepared from two recycled plastics, namely polypropylene and opaque poly (ethylene terephthalate), where the second one acted as a reinforcement phase. The raw materials were two commercial degrees of recycled post-consumer waste, i.e., rPP and rPET-O. Sheets were manufactured by a semi-industrial extrusion-calendering process. The mechanical and fracture behaviours of manufactured sheets were analyzed via tensile tests and the essential work of fracture approach. SEM micrographics of cryofractured sheets revelated the development of in situ rPP/rPET-O microfibrillar composites when 30 wt.% of rPET-O was added. It was observed that the yield stress was not affected with the addition of rPET-O. However, the microfibrillar structure increased the Young's modulus by more than a third compared with rPP, fulfilling the longitudinal value predicted by the additive rule of mixtures. Regarding the EWF analysis, the resistance to crack initiation was highly influenced by the resistance to its propagation owing to morphology-related instabilities during tearing. To analyze the initiation stage, a partition energy method was successfully applied by splitting the total work of fracture into two specific energetic contributions, namely initiation and propagation. The results revelated that the specific essential initiation-related work of fracture was mainly affected by rPET-O phase. Remarkably, its value was significantly improved by a factor of three with the microfibrillar structure of rPET-O phase. The results allowed the exploration of the potential ability of manufacturing in situ MFCs without a "precursor" morphology, providing an economical way to promote the recycling rate of PET-O, as this material is being discarded from current recycling processes.

11.
Viruses ; 13(9)2021 09 01.
Article in English | MEDLINE | ID: mdl-34578325

ABSTRACT

African swine fever (ASF) is one of the most important viral diseases of pigs caused by the ASF virus (ASFV). The virus is highly stable over a wide range of temperatures and pH and can survive in meat and meat products for several months, leading to long-distance transmission of ASF. Whole blood, serum, and organs from infected pigs are used routinely as approved sample types in the laboratory diagnosis of ASF. However, these sample types may not always be available. Here, we investigated meat exudate as an alternative sample type for the detection of ASFV-specific nucleic acids and antibodies. Pigs were infected with various ASFV strains: the highly virulent ASFV Malawi LIL 18/2 strain, the moderately-virulent ASFV Estonia 2014 strain, or the low-virulent ASFV OURT/88/3 strain. The animals were euthanized on different days post-infection (dpi), and meat exudates were collected and tested for the presence of ASFV-specific nucleic acids and antibodies. Animals infected with the ASFV Malawi LIL 18/2 developed severe clinical signs and succumbed to the infection within seven dpi, while pigs infected with ASFV Estonia 2014 also developed clinical signs but survived longer, with a few animals seroconverting before succumbing to the ASFV infection or being euthanized as they reached humane endpoints. Pigs infected with ASFV OURT/88/3 developed transient fever and seroconverted without mortality. ASFV genomic material was detected in meat exudate from pigs infected with ASFV Malawi LIL 18/2 and ASFV Estonia 2014 at the onset of viremia but at a lower amount when compared to the corresponding whole blood samples. Low levels of ASFV genomic material were detected in the whole blood of ASFV OURT/88/3-infected pigs, and no ASFV genomic material was detected in the meat exudate of these animals. Anti-ASFV antibodies were detected in the serum and meat exudate derived from ASFV OURT/88/3-infected pigs and in some of the samples derived from the ASFV Estonia 2014-infected pigs. These results indicate that ASFV genomic material and anti-ASFV antibodies can be detected in meat exudate, indicating that this sample can be used as an alternative sample type for ASF surveillance when routine sample types are unavailable or are not easily accessible.


Subject(s)
African Swine Fever Virus/genetics , African Swine Fever Virus/immunology , Antibodies, Viral/immunology , Exudates and Transudates , Genome, Viral , Genomics/methods , Meat , African Swine Fever/blood , African Swine Fever/virology , African Swine Fever Virus/pathogenicity , Animals , Antibodies, Viral/isolation & purification , Swine , Viral Proteins/genetics
12.
ACS Appl Bio Mater ; 4(4): 3067-3078, 2021 04 19.
Article in English | MEDLINE | ID: mdl-35014395

ABSTRACT

The present study aims to improve the interfacial bonding between hydroxyapatite particles (HAs) and polylactide (PLA) to enhance the mechanical performance and biocompatibility of bone implants based on HA/PLA. For this, one-shot surface functionalization of HA via plasma polymerization is developed. Taking advantage of acetylene plasma chemistry, the hydrophobicity of HA particles was finely tuned prior to their introduction into a PLA matrix via an extrusion process. The effect of the plasma power (20 or 100 W) on the composition of the plasma polymer film (PPF) formed on the HA surface was studied via Fourier transform infrared (FTIR) spectroscopy, time-of-flight secondary-ion mass spectrometry (ToF-SIMS), and X-ray photoelectron spectroscopy (XPS). The amount of PPF formed was evaluated via thermogravimetric analyses (TGA). Cytotoxicity of the modified HA particles was monitored by the WST-1 proliferation assay and lactate dehydrogenase (LDH) release and showed that independent on the studied conditions, cell viability remained above the 70% threshold and LDH accumulation changes were insignificant, suggesting good biocompatibility. Contact angle measurements and morphological and rheological analyses showed that the low working power promoted more hydrophobic surfaces and a better HA/PLA interface. Dynamic mechanical analyses revealed that the storage modulus at 37 °C increased for the composite containing functionalized particles by 1.5 times compared to the neat particle's composites. This work opens a route toward further one-shot development of improved scaffolds for bone tissue engineering.


Subject(s)
Bone Regeneration/drug effects , Coated Materials, Biocompatible/pharmacology , Osteoblasts/drug effects , Polymers/pharmacology , Coated Materials, Biocompatible/chemical synthesis , Coated Materials, Biocompatible/chemistry , Durapatite/chemistry , Durapatite/pharmacology , Humans , Materials Testing , Molecular Structure , Particle Size , Polyesters/chemistry , Polyesters/pharmacology , Polymers/chemistry , Tissue Engineering , Tissue Scaffolds/chemistry
13.
Sci Rep ; 11(1): 12617, 2021 06 16.
Article in English | MEDLINE | ID: mdl-34135396

ABSTRACT

Self-perception of ethnicity is a complex social trait shaped by both, biological and non-biological factors. We developed a comprehensive analysis of ethnic self-perception (ESP) on a large sample of Latin American mestizos from five countries, differing in age, socio-economic and education context, external phenotypic attributes and genetic background. We measured the correlation of ESP against genomic ancestry, and the influence of physical appearance, socio-economic context, and education on the distortion observed between both. Here we show that genomic ancestry is correlated to aspects of physical appearance, which in turn affect the individual ethnic self-perceived ancestry. Also, we observe that, besides the significant correlation among genomic ancestry and ESP, specific physical or socio-economic attributes have a strong impact on self-perception. In addition, the distortion among ESP and genomic ancestry differs across age ranks/countries, probably suggesting the underlying effect of past public policies regarding identity. Our results indicate that individuals' own ideas about its origins should be taken with caution, especially in aspects of modern life, including access to work, social policies, and public health key decisions such as drug administration, therapy design, and clinical trials, among others.


Subject(s)
Ethnicity/genetics , Ethnicity/psychology , Self Concept , Adult , Aged , Educational Status , Female , Genetic Background , Humans , Latin America/ethnology , Male , Middle Aged , Phenotype , Socioeconomic Factors
14.
BMC Pharmacol ; 10: 15, 2010 Nov 23.
Article in English | MEDLINE | ID: mdl-21092287

ABSTRACT

BACKGROUND: Interferon (IFN) alpha conjugation to polyethylene glycol (PEG) results in a better pharmacokinetic profile and efficacy. The aim of this study was to compare the pharmacokinetic, pharmacodynamic and safety properties of a new, locally developed, 40-kDa PEG-IFN alpha-2b preparation with a reference, commercially available PEG-IFN alpha-2a in healthy male volunteers. METHODS: A randomized, crossover, double-blind study with a 3-weeks washout period, was done. A single 180 micrograms PEG-IFN alpha-2 dose was administered subcutaneously in both groups. Sixteen apparently healthy male subjects were included. Serum PEG-IFN concentration was measured during 336 hours by an enzyme immunoassay (EIA). Other clinical and laboratory variables were used as pharmacodynamic and safety criteria. RESULTS: The pharmacokinetic comparison by EIA yielded a high similitude between the formulations. In spite of a high subject variability, the parameters' mean were very close (in all cases p > 0.05): AUC: 53623 vs. 44311 pg.h/mL; Cmax: 333 vs. 271 pg/mL; Tmax: 54 vs. 55 h; half-life (t1/2): 72.4 vs. 64.8 h; terminal elimination rate (lambda): 0.011 vs. 0.014 h(-1); mean residence time (MRT): 135 vs. 123 h for reference and study preparations, respectively. There were no significant differences with respect to the pharmacodynamic variables either: serum neopterin and beta-2 microglobulin levels, stimulation of 2'5' oligoadenylate synthetase expression, and serum IFN antiviral activity. A strong Spearman's rank order correlation (p < 0.01) between the pharmacokinetic and pharmacodynamic concentration-time curves was observed. Both products caused similar leukocyte counts diminution and had similar safety profiles. The most frequent adverse reactions were leukopenia, fever, thrombocytopenia, transaminases increase and asthenia, mostly mild. CONCLUSIONS: Both formulations are fully comparable from the pharmacokinetic, pharmacodynamic, and safety profiles. Efficacy trials can be carried out to confirm clinical similarity.


Subject(s)
Antiviral Agents/pharmacology , Antiviral Agents/pharmacokinetics , Interferon-alpha/pharmacology , Interferon-alpha/pharmacokinetics , Polyethylene Glycols/pharmacology , Polyethylene Glycols/pharmacokinetics , 2',5'-Oligoadenylate Synthetase/blood , 2',5'-Oligoadenylate Synthetase/genetics , Adult , Antiviral Agents/blood , Antiviral Agents/toxicity , Biomarkers/blood , Chemistry, Pharmaceutical , Cross-Over Studies , Double-Blind Method , Half-Life , Humans , Interferon alpha-2 , Interferon-alpha/blood , Interferon-alpha/toxicity , Leukopenia/chemically induced , Male , Metabolic Clearance Rate , Microbial Sensitivity Tests , Neopterin/blood , Polyethylene Glycols/toxicity , RNA, Messenger/metabolism , Recombinant Proteins , Young Adult , beta 2-Microglobulin/blood
15.
Rev Biol Trop ; 58(2): 621-34, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20527463

ABSTRACT

The main goal of this research was to obtain baseline field data of the composition of sponges, corals, and gorgonian assemblages that can be used as a reference for future analyses of anthropogenic impact. We tested the hypothesis that relatively homogeneous and well preserved reef units can present notable natural variability in the composition of their communities which are unassociated with changes in land proximity or a human impact gradient. Research was carried out in July 2006 at Los Colorados reef, located in the northwestern region of Pinar del Río Province, Cuba at 12 sampling stations. The biotopes selected were crest, terrace edge and spur and grove. Ecological indicators were diversity of corals, species composition, density of corals, hydrocorals, gorgonians and sponges, and density of selected coral species. A total of 2659 colonies of scleractineans corals representing 36 species were counted. The most abundant species in the crest biotope were Millepora alcicornis, Acropora palmata and Porites astreoides; in the terrace edge and spur and grove, the most abundant species were Siderastrea siderea, Stephanocoenia intersepta, Porites astreoides, Agaricia agaricites and Montastraea cavernosa. We found differences among sites for several indicators (e.g. density of corals, sponges and gorgonians and for selected species), but they could not be associated to any gradient of land influence or human impact. Therefore, sites inside a relatively homogeneous reef unit can present notable natural differences in the composition of their communities.


Subject(s)
Anthozoa/classification , Biodiversity , Environmental Monitoring , Porifera/classification , Animals , Cuba , Population Density
16.
J Imaging ; 6(9)2020 Sep 11.
Article in English | MEDLINE | ID: mdl-34460751

ABSTRACT

Current point cloud extraction methods based on photogrammetry generate large amounts of spurious detections that hamper useful 3D mesh reconstructions or, even worse, the possibility of adequate measurements. Moreover, noise removal methods for point clouds are complex, slow and incapable to cope with semantic noise. In this work, we present body2vec, a model-based body segmentation tool that uses a specifically trained Neural Network architecture. Body2vec is capable to perform human body point cloud reconstruction from videos taken on hand-held devices (smartphones or tablets), achieving high quality anthropometric measurements. The main contribution of the proposed workflow is to perform a background removal step, thus avoiding the spurious points generation that is usual in photogrammetric reconstruction. A group of 60 persons were taped with a smartphone, and the corresponding point clouds were obtained automatically with standard photogrammetric methods. We used as a 3D silver standard the clean meshes obtained at the same time with LiDAR sensors post-processed and noise-filtered by expert anthropological biologists. Finally, we used as gold standard anthropometric measurements of the waist and hip of the same people, taken by expert anthropometrists. Applying our method to the raw videos significantly enhanced the quality of the results of the point cloud as compared with the LiDAR-based mesh, and of the anthropometric measurements as compared with the actual hip and waist perimeter measured by the anthropometrists. In both contexts, the resulting quality of body2vec is equivalent to the LiDAR reconstruction.

17.
J Clin Endocrinol Metab ; 105(5)2020 05 01.
Article in English | MEDLINE | ID: mdl-32034419

ABSTRACT

CONTEXT: The reproductive axis is controlled by a network of gonadotropin-releasing hormone (GnRH) neurons born in the primitive nose that migrate to the hypothalamus alongside axons of the olfactory system. The observation that congenital anosmia (inability to smell) is often associated with GnRH deficiency in humans led to the prevailing view that GnRH neurons depend on olfactory structures to reach the brain, but this hypothesis has not been confirmed. OBJECTIVE: The objective of this work is to determine the potential for normal reproductive function in the setting of completely absent internal and external olfactory structures. METHODS: We conducted comprehensive phenotyping studies in 11 patients with congenital arhinia. These studies were augmented by review of medical records and study questionnaires in another 40 international patients. RESULTS: All male patients demonstrated clinical and/or biochemical signs of GnRH deficiency, and the 5 men studied in person had no luteinizing hormone (LH) pulses, suggesting absent GnRH activity. The 6 women studied in person also had apulsatile LH profiles, yet 3 had spontaneous breast development and 2 women (studied from afar) had normal breast development and menstrual cycles, suggesting a fully intact reproductive axis. Administration of pulsatile GnRH to 2 GnRH-deficient patients revealed normal pituitary responsiveness but gonadal failure in the male patient. CONCLUSIONS: Patients with arhinia teach us that the GnRH neuron, a key gatekeeper of the reproductive axis, is associated with but may not depend on olfactory structures for normal migration and function, and more broadly, illustrate the power of extreme human phenotypes in answering fundamental questions about human embryology.


Subject(s)
Gonadotropin-Releasing Hormone/metabolism , Neurons/physiology , Nose/abnormalities , Olfaction Disorders/congenital , Abnormalities, Multiple/genetics , Abnormalities, Multiple/metabolism , Abnormalities, Multiple/pathology , Abnormalities, Multiple/physiopathology , Adolescent , Adult , Aged , Child , Child, Preschool , Cohort Studies , Female , Follicle Stimulating Hormone/blood , Gonadotropin-Releasing Hormone/deficiency , Gonads/abnormalities , Gonads/pathology , Humans , Hypogonadism/genetics , Hypogonadism/metabolism , Hypogonadism/pathology , Hypogonadism/physiopathology , Infant , Luteinizing Hormone/blood , Male , Middle Aged , Neurogenesis/physiology , Neurons/metabolism , Olfaction Disorders/genetics , Olfaction Disorders/metabolism , Olfaction Disorders/physiopathology , Olfactory Pathways/metabolism , Olfactory Pathways/pathology , Organ Size , Young Adult
18.
Polymers (Basel) ; 12(1)2019 Dec 19.
Article in English | MEDLINE | ID: mdl-31861652

ABSTRACT

The effect of processing conditions on the final morphology of Poly(Lactic Acid) (PLA) with bio-based Polyamide 10.10 (PA) 70/30 blends is analyzed in this paper. Two types of PLA were used: Commercial (neat PLA) and a rheologically modified PLA (PLAREx), with higher melt elasticity produced by reactive extrusion. To evaluate the ability of in situ micro-fibrillation (f) of PA phase during blend compounding by twin-screw extrusion, two processing parameters were varied: i) Screw speed rotation (rpm); and ii) take-up velocity, to induce a hot stretching with different Draw Ratios (DR). The potential ability of PA-f in both bio-blends was evaluated by the viscosity (p) and elasticity (k') ratios determined from the rheological tests of pristine polymers. When PLAREx was used, the requirements for PA-f was fulfilled in the shear rate range observed at the extrusion die. Scanning electron microscopy (SEM) observations revealed that, unlike neat PLA, PLAREx promoted PA-f without hot stretching and the aspect ratio increased as DR increased. For neat PLA-based blends, PA-f was promoted during the hot stretching stage. DMTA analysis revealed that the use of PLAREx PLAREx resulted in a better mechanical performance in the rubbery region (T > Tg PLA-phase) due to the PA-f morphology obtained.

19.
Podium (Pinar Río) ; 18(3)dic. 2023.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1521338

ABSTRACT

La evaluación, como categoría didáctica en el proceso de enseñanza-aprendizaje de la carrera Licenciatura en Cultura Física y Deporte, enfrenta desafíos que obligan a los diferentes colectivos pedagógicos a proyectar acciones que le permitan una visión contextualizada e integral de la misma. La unidad del sistema de influencias educativas es una necesidad para la evaluación formativa, compartida, personalizada, centrada en evidencias de conocimiento, de producto y de desempeño en la formación y desarrollo de competencias en esta Carrera. El objetivo del trabajo es valorar el proceso evaluativo integrador de las competencias, en los estudiantes de la Práctica Laboral Investigativa de tercer año, de la Carrera de licenciatura en Cultura Física y Deporte, a través de la disciplina principal integradora Formación Laboral Investigativa. Para ello, se aplicaron métodos de investigación empíricos, como el análisis de documentos, la entrevista y la observación. Los resultados permitieron fundamentar una propuesta metodológica que potencie la evaluación integradora, sobre la base el enfoque integral físico-educativo, en el proceso de estudio. El diseño de los resultados fue de tipo experimental, en su variante pre-experimento. La aplicación parcial de la propuesta validó su pertinencia y contribuyó de forma favorable al mejoramiento del desempeño profesional y humano de los que participan.


A avaliação, como categoria didática no processo de ensino-aprendizagem do curso de Bacharelado em Cultura Física e Esporte, enfrenta desafios que obrigam os diferentes coletivos pedagógicos a planejar ações que permitam uma visão contextualizada e integral da mesma. A unidade do sistema de influências educacionais é uma necessidade para a avaliação formativa, compartilhada e personalizada, focada na evidência de conhecimento, produto e desempenho na formação e no desenvolvimento de competências nesse curso de graduação. O objetivo do estudo é avaliar o processo de avaliação integrativa das competências dos alunos do terceiro ano do Estágio de Pesquisa no Bacharelado em Cultura Física e Esporte, por meio da principal disciplina integrativa do Estágio de Pesquisa. Para isso, foram aplicados métodos de pesquisa empírica, como análise de documentos, entrevista e observação. Os resultados permitiram fundamentar uma proposta metodológica que aprimora a avaliação integrativa, com base na abordagem físico-educacional integral, no processo de estudo. O desenho dos resultados foi experimental, em sua variante pré-experimental. A aplicação parcial da proposta validou sua relevância e contribuiu favoravelmente para a melhoria do desempenho profissional e humano dos envolvidos.


Evaluation, as a didactic category in the teaching-learning process of the Bachelor's Degree in Physical Culture and Sports, faces challenges that force the different pedagogical groups to project actions that allow a contextualized and comprehensive vision of it. The unity of the system of educational influences is a necessity for formative, shared, personalized evaluation, focused on evidence of knowledge, product and performance in the training and development of competencies in this Career. The objective of the work is to assess the integrative evaluative process of the competencies, in the students of the third-year Investigative Work Practice, of the Bachelor's Degree in Physical Culture and Sports, through the main integrative discipline Investigative Work Training. To achieve this, empirical research methods were applied, such as document analysis, interviews and observation. The results allowed to base a methodological proposal that enhances the integrative evaluation, based on the comprehensive physical-educational approach, in the study process. The design of the results was experimental, in its pre-experiment variant. The partial application of the proposal validated its relevance and contributed favorably to the improvement of the professional and human performance of those who participate.

20.
Rev Esp Patol ; 51(1): 37-43, 2018.
Article in Spanish | MEDLINE | ID: mdl-29290322

ABSTRACT

Nevus lipomatosus cutaneus superficialis is a rare, hamartomatous disorder, characterized by the presence of ectopic mature adipose tissue within the superficial dermis. Lesions occur within the first three decades of life. We report four new cases, including a patient with the most extensive affectation reported to date, which was associated with massive lipomas in the subcutaneous cell tissue and diffuse lipomatosis. To our knowledge, it is the first report of this disorder in Cuba.


Subject(s)
Lipoma/pathology , Lipomatosis/pathology , Neoplasms, Multiple Primary/pathology , Nevus/pathology , Skin Diseases/pathology , Skin Neoplasms/pathology , Adult , Humans , Lipoma/complications , Lipomatosis/complications , Male , Middle Aged , Neoplasms, Multiple Primary/complications , Nevus/complications , Skin Diseases/complications , Skin Neoplasms/complications
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