bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Study of Capillary Filtration Coefficient (Kfc) Determination by a Manual and Automatic Perfusion System. Step by Step Technique Review
Authors: Bravo-Reyna C.C. , Torres-Villalobos G. , Aguilar-Blas N. , Frías-Guillén J. , Guerra-Mora J.R.
Published: December 2019

The purpose of calculating the capillary filtration coefficient is to experimentally evaluate edema formation in models of pulmonary ischemia-reperfusion injury. For many years, the obtaining of this coefficient implies a series of manual maneuvers during ex-vivo reperfusion of pulmonary arterial pressure, venous pressure and weight, as well as the calculation of the Kfc formula. Through automation, the calculation of capillary filtration coefficient could be easier and more efficient. To describe an automatic method designed in our laboratory to calculating the capillary filtration coefficient and compare with traditional determination of capillary filtration coefficient as gold standard method. An automatic three valve perfusion system was constructed, commanded by a mastery module connected to a graphical user interface. To test its accuracy, cardiopulmonary blocks of Wistar rats were harvested and distributed in manual (n=8) and automated (n=8) capillary filtration coefficient determination groups. Physiological parameters as pulmonary arterial pressure, pulmonary venous pressure, weight and capillary filtration coefficient were obtained. Results: Capillary filtration coefficient, pulmonary arterial pressure, venous arterial pressure shown no statistical significance difference between the groups. The automated perfusion system for obtaining Kfc was standardized and validated, giving reliable results without biases and making the process more efficient in terms of time and personal staff.
Relationship Between the Skin Surface Temperature Changes During Sprint Interval Testing Protocol and the Aerobic Capacity in Well-Trained Cyclists
Authors: Hebisz R. , Hebisz P. , Borkowski J. , Wierzbicka-Damska I. , Zatoń M.
Published: December 2019

The study investigated whether changes in body surface temperature in a sprint interval testing protocol (SITP) correlated with aerobic capacity in cyclists. The study involved 21 well-trained cyclists. Maximal aerobic power and maximal oxygen uptake relative to lean body mass (LBM-P(max) and LBM-VO(2max), respectively) were determined by incremental exercise testing on a cycle ergometer. SITP was administered 48 hours later and involved four 30-s maximal sprints interspersed with 90-s active recovery. Body surface temperature was recorded at the temple and arm and the delta difference between baseline temperature and temperature measured immediately after the first sprint (ΔTt(1) and ΔTa(1), respectively) and 80 seconds after the fourth sprint (ΔTt(4) and ΔTa(4), respectively) was calculated. Significant correlations were found between ΔTt(4) and LBM-P(max) and LBM-VO(2max) (r=0.63 and r=0.75, respectively) with no significant change in ΔTa(1) or ΔTa(4). Body surface temperature, measured at the temple region, can be used to indirectly assess aerobic capacity during maximal sprint exercise.
Thrombospondins Differentially Regulate Proteins Involved in Arterial Remodeling
Authors: Kassem M.M. , Helkin A. , Maier K.G. , Gahtan V.
Published: December 2019

Thrombospondins (TSPs) are matricellular glycoproteins expressed in response to vascular injury. TSP-1 and TSP-2 are promotors of arterial remodeling while TSP-5 is believed to be protective. The current study assessed the differential effect of TSPs on protein expression in vascular smooth muscle cells (VSMCs). We hypothesized that TSP-1, TSP-2 and TSP-5 would regulate VSMC proteins involved in arterial remodeling. Human VSMCs were exposed to TSP-1, -2, -5 or serum free media (24 hours). Cell lysates were used to assess the targets TSP-1, TSP-2, TSP-5 and CD44), while the culture media was used to detect TGF-β1, PDGF-BB, ANGPTL-4 and IL-8. Statistical analysis was performed by t-test and p< 0.05 was considered significant. All TSPs increased their own expression and TSP-5 increased TSP-2. TSP-1 and TSP-2 increased production of ANGPTL-4 and PDGF-BB, while TSP-5 only increased ANGPTL-4. TSP-1 increased exclusively TGF-β1 and CD44 production. TSP-2 increased TSP-1 expression. All TSPs decreased IL-8. The findings suggest that TSP-1 and TSP-2 may promote vascular remodeling, in part, by increasing ANGPTL-4, PDGF-BB and their own expression. TSP-5 did not upregulate the inflammatory mediators TSP-1, PDGF-BB or TGF-β1, but upregulated its own expression, which could be a protective mechanism against the response to vascular injury.
Comparison of Adiponectin Levels During the Menstrual Cycle Between Normal Weight and Overweight/Obese Young Females
Authors: Salem A.M. , Latif R. , Rafique N.
Published: December 2019

To compare serum adiponectin changes across the menstrual cycle between normal weight and overweight/obese young women and its correlation with serum estradiol. Young women (n=56) with regular menstrual cycle had been grouped according to their BMI into normal weight group (n=26) and overweight /obese group (n=30). Blood samples were drawn during early follicular (FP), pre-ovulatory (OP) and luteal phases (LP) of menstrual cycle for serum adiponectin and estradiol levels determination using enzyme-linked immunosorbent assay. Adiponectin serum level showed a significant decreasing pattern across the phases of menstrual cycle in normal weight group. This pattern was absent in the overweight/obese group. In addition, serum adiponectin was lower in overweight/obese group compared to normal weight subjects through all phases of menstrual cycle. No correlation was found between adiponectin and estradiol levels in both groups. A significant variation of serum adiponectin level was detected across the menstrual cycle in females with normal weight. In comparison, overweight/obese group showed a relatively stable adiponectin level throughout the cycle. This lack of adiponectin variation might be added to the complex mechanisms lies behind obesity-related female infertility.
Time and Dose-Dependent Effects of Viscum Album Quercus on Rabbit Spermatozoa Motility and Viability in Vitro
Authors: Halo M. , Massanyi P. , Gren A. , Lasak A. , Slanina T. , Ondruska L. , Muchacka R. , Galbavy D. , Ivanic P. , Schneir E.R. , Formicki G.
Published: December 2019

The target of this study was to evaluate the effect of extract of the European mistletoe – Viscum album quercus L. on spermatozoa motility and viability in vitro. The CASA system was used to determine the spermatozoa motility parameters at different time intervals (0, 1, 2 and 3 h) and spermatozoa viability was determined in five different doses of Viscum album quercus L [10 (QA), 6.6 (QB), 3.3 (QC), 2.5 (QD) and 2 (QE) mg/ml]. Results in experimental groups detected a significant deterioration on rabbit spermatozoa after 1, 2 and 3 hours, compared to the control. The initial total spermatozoa motility showed increased value for all doses of Viscum album quercus in comparison to control. After in vitro culture a dose–dependent decrease (QA: reduction of 69.7 %, QB: reduction of 40.9 %) was found. For the progressive spermatozoa most significant decrease (86.8 % for QA vs. 48.5 % for QB) was detected compared to the control after 3 hours of culture. Spermatozoa viability (MTT test) was decreased in all experiment groups at the end of experiment, but the differences were not significant. Significant alterations of membrane integrity were found in groups with the highest Viscum album quercus concentration (QA, QB), but acrosome integrity showed no significant changes. Results suggest negative dose– and time–dependent effect of Viscum album quercus at higher doses on spermatozoa motility and viability parameters in vitro.
High-Fructose Diet-Induced Hypertriglyceridemia Is Associated With Enhanced Hepatic Expression of ACAT2 in Rats
Authors: Ichigo Y. , Takeshita A. , Hibino M. , Nakagawa T. , Hayakawa T. , Patel D. , Field C.J. , Shimada M.
Published: December 2019

High levels of fructose induce hypertriglyceridemia, characterized by excessive levels of triglyceride-rich lipoproteins such as very low-density lipoprotein (VLDL); however, the underlying mechanisms are poorly understood. The aim of this short communication was to examine hepatic changes in the expression of genes related to cholesterol metabolism in rats with hypertriglyceridemia induced by high-fructose or high-glucose diets. Rats were fed a 65 % (w/w) glucose diet or a 65 % (w/w) fructose diet for 12 days. Serum levels of triglycerides, total cholesterol, and VLDL+LDL-cholesterol, hepatic levels of triglycerides and cholesterol, and ACAT2 expression at the gene and protein levels were significantly higher in the fructose diet group compared to the glucose diet group. The hepatic levels of Abcg5/8 were lower in the fructose group than in the glucose group. Serum high-density lipoprotein (HDL)-cholesterol and hepatic expression levels of Hmgcr, Ldlr, Acat1, Mttp, Apob, and Cyp7a1 did not differ significantly between groups. These findings suggest that high-fructose diet-induced hypertriglyceridemia is associated with increased hepatic ACAT2 expression.
Is Renal β-Adrenergic-WNK4-NCC Pathway Important in Salt Hypertension of Dahl Rats?
Authors: Zicha J. , Hojná S. , Vaňourková Z. , Kopkan L. , Vaněčková I.
Published: December 2019

In 2011 Fujita and coworkers proposed that β-adrenergic stimulation causes decreased serine/threonine-protein kinase WNK4 transcription leading to the activation of Na-Cl cotransporter (NCC) which participates in salt sensitivity and salt hypertension development in rodents. The aim of our study was to investigate whether the above hypothesis is also valid for salt hypertension of Dahl rats, which are characterized by high sympathetic tone and abnormal renal sodium handling. Male 8-week-old salt-sensitive (SS/Jr) and salt-resistant (SR/Jr) Dahl rats were fed either low-salt diet (LS, 0.4 % NaCl) or high-salt diet (HS, 4 % NaCl) for 6 weeks. Half of the animals on either diet were chronically treated with non-selective β-blocker propranolol (100 mg/kg/day). At the end of the experiment diuresis and sodium excretion were measured prior and after hydrochlorothiazide injection (HCTZ, 10 mg/kg i.p.). Furthermore, blood pressure (BP), heart rate (HR), sympathetic (pentolinium 5 mg/kg i.v.) and NO-dependent (L-NAME 30 mg/kg i.v.) BP components were determined. Chronic HS diet feeding increased BP through sympathoexcitation in SS/Jr but not in SR/Jr rats. Concomitant propranolol treatment did not lower BP in either experimental group. Under the conditions of low salt intake HCTZ increased diuresis, natriuresis and fractional sodium excretion in SR/Jr but not in SS/Jr rats. HS diet feeding attenuated renal response to HCT in SR/Jr rats, whereas no HCTZ effect was observed in SS/Jr rats fed HS diet. Propranolol treatment did not modify diuresis or natriuresis in any experimental group. In conclusions, our present data do not support the idea on the essential importance of renal β-adrenergic-WNK4-NCC pathway in pathogenesis and/or maintenance of salt hypertension in Dahl rats.
La Norma ISO 21001:2018 – Apéndice normativo y su impacto en estudiantes de educación superior de Lima
Authors: Rivera Paipay Katelinen Mirian , Tupac Yupanqui Bustamante Miguel Ángel
Published: December 2019

El propósito de la investigación es determinar el impacto de la norma ISO 21001:2018 - apéndice normativo en estudiantes del último semestre del programa de educación pre escolar de una institución de educación superior de Lima. Es de coyuntura analizar temas de calidad educativa, puesto que los sistemas educativos de diversas partes del mundo, vienen analizando el servicio que están brindando a su público objetivo: estudiantes. Las instituciones que brindan servicios de educación están alineando sus sistemas de gestión de la calidad acogiéndose a normativas que permitan garantizar esa calidad educativa que los visibilice como opciones atractivas. La investigación es de tipo descriptivo y explicativo, el diseño de investigación es no experimental porque solo se hace un análisis de impacto entre las variables. La técnica de investigación ha sido la encuesta. La población está conformada por 150 estudiantes del último semestre del programa de educación pre escolar, teniendo una muestra de 109 estudiantes con un nivel de confianza del 95% y un margen de error del 5%. Finalmente se concluye que tiene un impacto positivo en estudiantes del último semestre del programa de educación pre escolar de una institución de educación superior de Lima.
Desempeño de las cien firmas más grandes y el crecimiento de la economía ecuatoriana. 2010-2016
Authors: Jativa Pesantes María Augusta
Published: December 2019

El presente estudio compara el comportamiento de las cien mayores firmas privadas registradas ante la Superintendencia de Compañías que se corresponden con la evolución del ingreso, renta o Producto Interno Bruto –PIB- del Ecuador de los sectores económicos, durante el período comprendido entre 2010 y 2016; incluye el desempeño del empleo, la inversión y los precios, por ser datos significativos.

El PIB es una magnitud que sirve para medir el comportamiento de una economía, su inversión y empleo; si su medición se muestra creciente, habrá mayor bienestar en la sociedad. El nivel de empleo se relaciona directamente con la forma como el talento humano contribuye a esa producción de manera plena, no precaria y mejora aún más si hay un mejor nivel de capitalización, por tanto, inversión. Por otro lado, toda firma es una organización que busca alcanzar los fines usando los medios y coordinando los intercambios tanto en el mercado de factores como en el de productos y opera en cumplimiento de la función empresarial para alcanzar objetivos valiosos para la sociedad.
Automatic Determination of the Parameters of Electrical Signals and Functional Responses of Plants Using the Wavelet Transformation Method
Authors: Mudrilov Maxim , Katicheva Lyubov , Ladeynova Maria , Balalaeva Irina , Sukhov Vladimir , Vodeneev Vladimir
Published: December 2019

Smart agriculture management systems with real-time control of plant health and vegetation are recognized as one of the crucial technologies determining agriculture development, playing a fundamental role in reducing yield losses and improving product quality. The earliest plant responses to various adverse factors are propagating stress signals, including electrical ones, and the changes in physiological processes induced by them. Among the latter, photosynthesis is of particular interest due to its key role in the production process. Of practical importance, photosynthesis activity can be registered not only in contact mode but by remote sensing using optical methods. The aim of the present work was to develop the approach to automatic determination of the main parameters of electrical signals and changes in photosynthesis activity and transpiration using continuous wavelet transform (CWT). Applying CWT based on derivatives of the Gaussian function allows accurate determination of the parameters of electrical signals as well as induced physiological responses. Moreover, CWT was applied for spatio-temporal mapping of the photosynthesis response to stress factors in pea leaf. The offered approach allowed automatic identification of the response start time in every pixel and visualization of the change propagation front. The results indicate high potential of CWT for automatic assessment of plants stress, including monitoring of plant health in large-scale agricultural lands and automated fields.
Anther Extrusion and Its Association with Fusarium Head Blight in CIMMYT Wheat Germplasm
Authors: Xu Kaijie , He Xinyao , Dreisigacker Susanne , He Zhonghu , Singh Pawan K.
Published: December 2019

Pronounced anther extrusion (AE) is associated with field resistance to Fusarium head blight (FHB), one of the most devastating diseases of wheat globally. In this study, two recombinant inbred line (RIL) populations were used to map quantitative trait loci (QTL) for AE and field FHB resistance and to investigate the association of both traits at the genetic level. Furthermore, two panels of International Maize and Wheat Improvement Center (CIMMYT) wheat breeding lines were evaluated to describe the phenotypic association between the two traits in detail. Highly significant negative correlation was identified between AE and FHB severity in the two populations and the two panels, with r-values ranging from 0.55 to 0.74. QTL analysis in the two RIL populations identified 12 QTL for AE and nine for FHB resistance, of which five QTL located on chromosomes 3BL, 4BS, 4DS, 5AL, and 5BL were associated with both AE and FHB, collectively explaining over 50% of phenotypic variation for FHB. The QTL on chromosomes 4BS, 4DS, 5AL, and 5BL were closely linked to Rht-B1, Rht-D1, Vrn-A1, and Vrn-B1 genes, respectively. In conclusion, AE is closely related to field FHB resistance and could be used as a morphological marker in wheat breeding for field FHB resistance.
Evaluation of Potential Volatile Allelopathic Plants from Bangladesh, with Sapindus mukorossi as a Candidate Species
Authors: Begum Kohinoor , Shammi Mashura , Hasan Nazmul , Appiah Kwame Sarpong , Fujii Yoshiharu
Published: December 2019

This study focuses on identifying volatile emissions from plants with potential plant growth inhibitory activity. The aim of this study was to evaluate plant species from the Asian country Bangladesh for new, potential volatile allelopathic species. A total of 103 plant samples from 40 different families were assessed with the dish pack (DP) method. About 25% of the evaluated plant samples influenced (inhibited or stimulated) the growth of lettuce, due to the presence of potentially volatile allelochemicals. The pericarp of Sapindus mukorossi Gaertn. caused the lowest radicle elongation (3% of control) of the lettuce. This was followed by the leaves of Cassia nodosa Roxb. (34.4%) and the root of Kaempferia galangal L. (43.4%), in that order. Therefore, the pericarp of S. mukorossi is reported from this study as a new potential volatile allelopathic species. On the contrary, the leaves of Gynostemma pentaphyllum Thunb. had a stimulatory effect on the hypocotyl elongation of lettuce seedlings (156% of control). The single petri dish (SPD), a new method, was also adapted to justify the potentiality of the growth control of particular allelopathic species. This study revealed that the new potentially volatile allelopathic plant species could be further explored in sustainable weed management.
Simulating Long-Term Development of Greenhouse Gas Emissions, Plant Biomass, and Soil Moisture of a Temperate Grassland Ecosystem under Elevated Atmospheric CO2
Authors: Liebermann Ralf , Breuer Lutz , Houska Tobias , Kraus David , Moser Gerald , Kraft Philipp
Published: December 2019

The rising atmospheric CO2 concentrations have effects on the worldwide ecosystems such as an increase in biomass production as well as changing soil processes and conditions. Since this affects the ecosystem’s net balance of greenhouse gas emissions, reliable projections about the CO2 impact are required. Deterministic models can capture the interrelated biological, hydrological, and biogeochemical processes under changing CO2 concentrations if long-term observations for model testing are provided. We used 13 years of data on above-ground biomass production, soil moisture, and emissions of CO2 and N2O from the Free Air Carbon dioxide Enrichment (FACE) grassland experiment in Giessen, Germany. Then, the LandscapeDNDC ecosystem model was calibrated with data measured under current CO2 concentrations and validated under elevated CO2. Depending on the hydrological conditions, different CO2 effects were observed and captured well for all ecosystem variables but N2O emissions. Confidence intervals of ensemble simulations covered up to 96% of measured biomass and CO2 emission values, while soil water content was well simulated in terms of annual cycle and location-specific CO2 effects. N2O emissions under elevated CO2 could not be reproduced, presumably due to a rarely considered mineralization process of organic nitrogen, which is not yet included in LandscapeDNDC.
Combining Orchardgrass and Alfalfa: Effects of Forage Ratios on In Vitro Rumen Degradation and Fermentation Characteristics of Silage Compared with Hay
Authors: Xue Zhulin , Liu Nan , Wang Yanlu , Yang Hongjian , Wei Yuqi , Moriel Philipe , Palmer Elizabeth , Zhang Yingjun
Published: December 2019

This study aimed to investigate the effects of different forage ratios of orchardgrass (Dactylis glomerata) and alfalfa (Medicago sativa) on in vitro rumen degradation and fermentation characteristics. Orchardgrass and alfalfa were harvested separately and prepared as hay and silage mixtures at ratios of 100:0, 75:25, 50:50, 25:75, and 0:100 (w/w on a dry matter basis) and anaerobically incubated for 48 h with rumen fluid obtained from lactating dairy cows. Fermented residues and cultured fluids were used to determine nutrient degradability, fermentation parameters, and associative effect indices. Increasing the proportion of alfalfa in hay and silage mixtures quadratically increased in vitro organic matter disappearance (IVOMD, up +5.14%) and marginally decreased in vitro neutral detergent fiber disappearance (NDFD, down −1.79%). Meanwhile, increasing the proportion of alfalfa accelerated the rumen fermentation process (e.g., gas production) and remarkably enhanced the growth of rumen microbes as indicated by microbial protein production (MCP, 13.4% increase). Increments of rumen degradability and methane production were more pronounced in silage mixtures than hay mixtures. In combination, a forage ratio of 50:50 for orchardgrass and alfalfa is recommended for both hay and silage in order to improve the feed use potential in ruminants.
Enteric Methane Emissions of Dairy Cows Predicted from Fatty Acid Profiles of Milk, Cream, Cheese, Ricotta, Whey, and Scotta
Authors: Bittante Giovanni , Bergamaschi Matteo
Published: December 2019

Enteric methane emissions (EME) of ruminants contribute to global climate change, but any attempt to reduce it will need an easy, inexpensive, and accurate method of quantification. We used a promising indirect method for estimating EMEs of lactating dairy cows based on the analysis of the fatty acid (FA) profile of their milk. The aim of this preliminary study was to assess milk from four single samplings (morning whole, evening whole, evening partially skimmed, and vat milks) as alternatives to reference whole milk samples from two milkings. Three fresh products (cream, cheese, and ricotta), two by-products (whey and scotta), and two long-ripened cheeses (6 and 12 months) were also assessed as alternative sources of information to reference milk. The 11 alternative matrices were obtained from seven experimental cheese- and ricotta-making sessions carried out every two weeks following the artisanal Malga cheese-making procedure using milk from 148 dairy cows kept on summer highland pastures. A total of 131 samples of milk, dairy products, and by-products were analyzed to determine the milk composition and to obtain detailed FA profiles using bi-dimensional gas-chromatography. Two equations taken from a published meta-analysis of methane emissions measured in the respiration chambers of cows on 30 different diets were applied to the proportions of butyric, iso-palmitic, iso-oleic, vaccenic, oleic, and linoleic acids out of total FAs to predict methane yield per kg of dry matter ingested and methane intensity per kg of fat and protein corrected milk produced by the cows. Methane yield and intensity could be predicted from single milk samples with good accuracy (trueness and precision) with respect to those predicted from reference milk. The fresh products (cream, cheese and ricotta) generally showed good levels of trueness but low precision for predicting both EME traits, which means that a greater number of samples needs to be analyzed. Among by-products, whey could be a viable alternative source of information for predicting both EME traits, whereas scotta overestimated both traits and showed low precision (due also to its very low fat content). Long-ripened cheeses were found to be less valuable sources of information, although six-month cheese could, with specific correction factors, be acceptable sources of information for predicting the methane yield of lactating cows. These preliminary results need to be confirmed by further study on different dairy systems and cheese-making technologies but offer new insight into a possible easy method for monitoring the EME at the field level along the dairy chain.
Psychological Correlates of Attitudes toward Pet Relinquishment and of Actual Pet Relinquishment: The Role of Pragmatism and Obligation
Authors: Jacobetty Rita , Lopes Diniz , Fatjó Jaume , Bowen Jonathan , Rodrigues David L.
Published: December 2019

Understanding pet relinquishment is essential to inform interventions and assess their impact. In a cross-sectional study, we explored how attitudes of lack of obligation and pragmatism toward pet relinquishment correlated with, and differed according to, sociodemographic characteristics (age, gender, education, political orientation, religion, income, and household), previous animal experience, and owner perceptions of animals (perceiving pet as a burden, motives for pet relinquishment, regret having a pet, and general trust in pets). We adapted and developed three scales to measure attitudes toward pet relinquishment (ATPR), motives for pet relinquishment (MPR), and general trust in pets (GTP), revealing good psychometric qualities. Hierarchical linear regressions showed that attitudes of lack of obligation toward pet relinquishment were stronger in older people, those perceiving their pet as a burden, and those with lower general trust in pets. Attitudes of pragmatism toward pet relinquishment were stronger in men, those who were main pet caretakers, those perceiving their pet as a burden, those with higher motives for pet relinquishment, and those with lower general trust in pets. Furthermore, results showed that past pet relinquishment behavior was predicted by attitudes of pragmatism, but not attitudes of lack of obligation.
Simple Carbohydrate Derivatives Diminish the Formation of Biofilm of the Pathogenic Yeast Candida albicans
Authors: Ishchuk Olena P. , Sterner Olov , Ellervik Ulf , Manner Sophie
Published: December 2019

The opportunistic human fungal pathogen Candida albicans relies on cell morphological transitions to develop biofilm and invade the host. In the current study, we developed new regulatory molecules, which inhibit the morphological transition of C. albicans from yeast-form cells to cells forming hyphae. These compounds, benzyl α-l-fucopyranoside and benzyl β-d-xylopyranoside, inhibit the hyphae formation and adhesion of C. albicans to a polystyrene surface, resulting in a reduced biofilm formation. The addition of cAMP to cells treated with α-l-fucopyranoside restored the yeast-hyphae switch and the biofilm level to that of the untreated control. In the β-d-xylopyranoside treated cells, the biofilm level was only partially restored by the addition of cAMP, and these cells remained mainly as yeast-form cells.
Exposure to Toxic Heavy Metals Can Influence Homocysteine Metabolism?
Authors: Ledda Caterina , Cannizzaro Emanuele , Lovreglio Piero , Vitale Ermanno , Stufano Angela , Montana Angelo , Li Volti Giovanni , Rapisarda Venerando
Published: December 2019

Background: Homocysteine is a sulfur amino acid whose metabolism is activated in two pathways: remethylation to methionine, which requires folate and vitamin B12, and transsulfuration to cystathionine, which needs pyridoxal-5’-phosphate. High homocysteine level increases the risk of developing heart disease, stroke, peripheral vascular diseases, and cognitive impairment. Some evidence showed that exposure to these metals increased plasma homocysteine levels. Methods: A systematic review was carried out to clarify the relationship between homocysteine blood levels and exposure to toxic heavy metals (Lead, Cadmium, Mercury, and Chromium). Results: The results of this systematic review indicate that exposure to Pb, Cr, Cd, and Hg is connected with nonphysiological homocysteine levels or vitamin B12 and folate serum concentrations. Conclusions: These findings reinforce the importance of involvement in exposure to heavy metals in homocysteine metabolism. This supports the role of blood metals as potential upstream modifiable risk factors to prevent the development of other established risk factors as hyperhomocysteinemia.
The Inhibitory Effects of Slow-Releasing Hydrogen Sulfide Donors in the Mechanical Allodynia, Grip Strength Deficits, and Depressive-Like Behaviors Associated with Chronic Osteoarthritis Pain
Authors: Batallé Gerard , Cabarga Laura , Pol Olga
Published: December 2019

Osteoarthritis and its associated comorbidities are important clinical problems that have a negative impact on the quality of life, and its treatment remains unresolved. We investigated whether the systemic administration of slow-releasing hydrogen sulfide (H2S) donors, allyl isothiocyanate (A-ITC) and phenyl isothiocyanate (P-ITC), alleviates chronic osteoarthritis pain and the associated emotional disorders. In C57BL/6 female mice with osteoarthritis pain induced by the intra-articular injection of monosodium iodoacetate, we evaluated the effects of repeated administration of A-ITC and P-ITC on the (i) mechanical allodynia and grip strength deficits; (ii) emotional conducts; and (iii) glial activity and expression of inducible nitric oxide synthase (NOS2), phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt), and antioxidant enzymes (heme oxygenase 1, NAD(P)H:quinone oxidoreductase-1, glutathione S-transferase mu 1 and alpha 1) in the hippocampus. The administration of A-ITC and P-ITC inhibited the mechanical allodynia, the grip strength deficits, and the depressive-like behaviors accompanying osteoarthritis. Both treatments inhibited microglial activation, normalized the upregulation of NOS2 and PI3K/p-Akt, and maintained high levels of antioxidant/detoxificant enzymes in the hippocampus. Data suggest that treatment with low doses of slow-releasing H2S donors might be an interesting strategy for the treatment of nociception, functional disability, and emotional disorders associated with osteoarthritis pain.
Joint Spatial-Spectral Smoothing in a Minimum-Volume Simplex for Hyperspectral Image Super-Resolution
Authors: Ma Fei , Yang Feixia , Ping Ziliang , Wang Wenqin
Published: December 2019

The limitations of hyperspectral sensors usually lead to coarse spatial resolution of acquired images. A well-known fusion method called coupled non-negative matrix factorization (CNMF) often amounts to an ill-posed inverse problem with poor anti-noise performance. Moreover, from the perspective of matrix decomposition, the matrixing of remotely-sensed cubic data results in the loss of data’s structural information, which causes the performance degradation of reconstructed images. In addition to three-dimensional tensor-based fusion methods, Craig’s minimum-volume belief in hyperspectral unmixing can also be utilized to restore the data structure information for hyperspectral image super-resolution. To address the above difficulties simultaneously, this article incorporates the regularization of joint spatial-spectral smoothing in a minimum-volume simplex, and spatial sparsity—into the original CNMF, to redefine a bi-convex problem. After the convexification of the regularizers, the alternating optimization is utilized to decouple the regularized problem into two convex subproblems, which are then reformulated by separately vectorizing the variables via vector-matrix operators. The alternating direction method of multipliers is employed to split the variables and yield the closed-form solutions. In addition, in order to solve the bottleneck of high computational burden, especially when the size of the problem is large, complexity reduction is conducted to simplify the solutions with constructed matrices and tensor operators. Experimental results illustrate that the proposed algorithm outperforms state-of-the-art fusion methods, which verifies the validity of the new fusion approach in this article.
Improvement in Land Cover and Crop Classification based on Temporal Features Learning from Sentinel-2 Data Using Recurrent-Convolutional Neural Network (R-CNN)
Authors: Mazzia Vittorio , Khaliq Aleem , Chiaberge Marcello
Published: December 2019

Understanding the use of current land cover, along with monitoring change over time, is vital for agronomists and agricultural agencies responsible for land management. The increasing spatial and temporal resolution of globally available satellite images, such as provided by Sentinel-2, creates new possibilities for researchers to use freely available multi-spectral optical images, with decametric spatial resolution and more frequent revisits for remote sensing applications such as land cover and crop classification (LC&CC), agricultural monitoring and management, environment monitoring. Existing solutions dedicated to cropland mapping can be categorized based on per-pixel based and object-based. However, it is still challenging when more classes of agricultural crops are considered at a massive scale. In this paper, a novel and optimal deep learning model for pixel-based LC&CC is developed and implemented based on Recurrent Neural Networks (RNN) in combination with Convolutional Neural Networks (CNN) using multi-temporal sentinel-2 imagery of central north part of Italy, which has diverse agricultural system dominated by economic crop types. The proposed methodology is capable of automated feature extraction by learning time correlation of multiple images, which reduces manual feature engineering and modeling crop phenological stages. Fifteen classes, including major agricultural crops, were considered in this study. We also tested other widely used traditional machine learning algorithms for comparison such as support vector machine SVM, random forest (RF), Kernal SVM, and gradient boosting machine, also called XGBoost. The overall accuracy achieved by our proposed Pixel R-CNN was 96.5%, which showed considerable improvements in comparison with existing mainstream methods. This study showed that Pixel R-CNN based model offers a highly accurate way to assess and employ time-series data for multi-temporal classification tasks.
Impacts of MT-HVDC Systems on Enhancing the Power Transmission Capability
Authors: Raza Ali , Shakeel Armughan , Altalbe Ali , O. Alassafi Madini , Yasin Abdul Rehman
Published: December 2019

In this paper, improvement in the power transfer capacity of transmission lines (TLs) by utilizing a multi-terminal high voltage direct current (MT-HVDC) grid is discussed. A multi-terminal HVDC grid designed for wind power can be used as an extra transmission path in interconnected systems during low wind conditions, and provides extra dynamic stability and security. This paper deals with the power transfer capacity as well as the small signal (SS) stability assessments in less damped oscillations accompanying inter area modes. Computation of the maximum allowable power transfer capability is assessed via DC optimal power flow-based control architecture, permitting more power transfer with a definite security margin. The test system is assessed with and without the exploitation of MT-HVDC grid. Simulation work is done using a generic computational framework i.e., international council on large electric systems (CIGRE) B4 test bench with a Kundur’s two area system, shows that voltage source converters (VSCs) provide excellent control and flexibility, improving the power transfer capability keeping the system stable.
Influence of Swing-Foot Strike Pattern on Balance Control Mechanisms during Gait Initiation over an Obstacle to Be Cleared
Authors: Artico Romain , Fourcade Paul , Teyssèdre Claudine , Caderby Teddy , Delafontaine Arnaud , Yiou Eric
Published: December 2019

Gait initiation (GI) over an obstacle to be cleared is a functional task that is highly challenging for the balance control system. Two swing-foot strike patterns were identified during this task—the rearfoot strike (RFS), where the heel strikes the ground first, and the forefoot strike (FFS), where the toe strikes the ground first. This study investigated the effect of the swing-foot strike pattern on the postural organisation of GI over an obstacle to be cleared. Participants performed a series of obstacle clearance tasks with the instruction to strike the ground with either an FFS or RFS pattern. Results showed that anticipatory postural adjustments in the frontal plane were smaller in FFS than in RFS, while stability was increased in FFS. The vertical braking of the centre of mass (COM) during GI swing phase was attenuated in FFS compared to RFS, leading to greater downward centre of mass velocity at foot contact in FFS. In addition, the collision forces acting on the foot were smaller in FFS than in RFS, as were the slope of these forces and the slope of the C7 vertebra acceleration at foot contact. Overall, these results suggest an interdependent relationship between balance control mechanisms and foot strike pattern for optimal stability control.
Rockfall Investigation and Hazard Assessment from Nang County to Jiacha County in Tibet
Authors: Liu Haiyang , Wang Xueliang , Liao Xiaohui , Sun Juanjuan , Zhang Su
Published: December 2019

The influences of rockfall on human engineering have been increasing in Tibet with the rapid development of the western region of China. This study proposed a multi-approach to carry out rockfall investigation and hazard assessment. As a case study, the rockfall hazard from Nang County to Jiacha County in Tibet was assessed. Firstly, we summarized the characteristics of spatial distributions of typical rockfall sources using Digital Elevation Model (DEM) and unmanned aerial vehicle (UAV) aerial images with resolution of 10 m. According to the thresholds of slope angle, slope aspect and elevation distribution of typical rockfall sources, we obtained all of the rockfall source areas in study area semi-automatically in ArcGIS platform. Secondly, we improved the efficiency and accuracy of detailed field investigation by using a three-dimensional (3D) point cloud model and rock mass structure extraction software. According to the analysis result, the dominant joint set was J1, whose orientation was basically consistent with the Yarlung Tsangpo Fault. The combination of J1, J2 and J4 cut the rock mass into blocks of wedge with J1 as potential sliding planes. It was indicated that the stability of the rock mass in study area was mainly controlled by the characters of joint sets. Finally, we applied the improved reclassification criteria of the Rockfall Hazard Vector (RHV) method in rockfall hazard assessment according to protection capabilities of the current protection facilities, making the result more valuable for geohazards prevention work. Based on this multi-approach, we obtained that 10.92% of the 306 provincial highway and 9.38% of the power line were threatened by potential rockfall hazards in study area. The hazard assessment results of study area were also of certain guiding value to the linear project planning and geohazards prevention work.
Evidence of Hierarchy in the Drainage Basins Size Distribution of Greece Derived from ASTER GDEM-v2 Data
Authors: Vallianatos Filippos , Kouli Maria
Published: December 2019

The drainage basins of Greece are analyzed in terms of hierarchy and discussed in view of Tsallis Entropy. This concept has been successfully used in a variety of complex systems, where fractality, memory and long-range interactions are dominant. The analysis indicates that the statistical distribution of drainage basins’ area in Greece, presents a hierarchical pattern that can be viewed within the frame of non-extensive statistical physics. Our work was based on the analysis of the ASTER GDEM v2 Digital Elevation Model of Greece, which offers a 30 m resolution, creating an accurate drainage basins’ database. Analyzing the drainage size (e.g., drainage basin area)-frequency distribution we discuss the connection of the observed power law exponents with the Tsallis entropic parameters, demonstrating the hierarchy observed in drainage areas for the set created for all over Greece and the subsets of drainages in the internal and external Hellenides that are the main tectonic structures in Greece. Furthermore, we discuss in terms of Tsallis entropy, the hierarchical patterns observed when the drainages are classified according to their relief or the Topographic Position Index (TPI). The deviation of distribution from power law for large drainages area is discussed.
Controllable Combustion Synthesis of SiC Nanowhiskers in a Si-C-N System: The Role of the Catalyst
Authors: Xia Min , Guo Hong-Yan , Hussain Muhammad Irfan
Published: December 2019

Silicon carbide (SiC) nanowhiskers (NWs) constitute an important type of optical and structural materials. Herein, SiC NWs were successfully combustion synthesized (CSed) in a Si-C-N system using tungsten (W) as a catalyst. Scanning electron microscopy, transmission electron microscopy, and X-ray diffraction were used to characterize the SiC NWs. Results of morphological characterization indicated that the W-catalyzed CSed SiC NWs products were fluffy from surface to the core, and they were about several hundred micrometers in length with diameters less than 1 μm. For the comprehensive understanding of the initial growing progress of W-catalyzed CSed SiC NWs, the absorption behavior of C, N, and Si atoms on the crystal planes of W (100), W (110), and W (111) surfaces was investigated by using first-principles calculations. The calculated surface energy (Esurf) of the studied W surfaces and the absorption energy of C, N, and Si atoms on different sites, indicate that the C atom has a priority to sink to the nanometer catalysts grain of W, and the pre-sunk C atom then reacts with Si atom to form NWs.
Applications of Capacitive Imaging in Human Skin Texture and Hair Analysis
Authors: Bontozoglou Christos , Xiao Perry
Published: December 2019

This article focuses on the extraction of information from human skin and scalp hair for evaluation of a subject’s condition in the cosmetic and pharmaceutical industries. It uses capacitive images from existing hand-held research equipment and it applies image processing algorithms to expand their possible applications. The literature review introduces the readers into the field of skin research, and it highlights pieces of information that can be extracted by in vivo skin and ex vivo hair measurements. Then, the selected scientific equipment is presented, and Maxwell-based electrostatic simulations are employed to evaluate the measurement apparatus. Image analysis algorithms are suggested for (a) the detection of polygons on the human skin texture, (b) the estimation of wrinkles length and (c) the observation of hair water sorption capabilities by capacitive imaging systems. Finally, experiments are conducted to evaluate the performance of the presented algorithms and the results are compared with the literature. The results indicate that capacitive imaging systems can be used for skin age classification, detection and tracking of skin artifacts (e.g., wrinkles, moles or scars) and calculation of water content in hair samples.
Displacement-Dependent Damping Inerter System for Seismic Response Control
Authors: Zhao Zhipeng , Zhang Ruifu , Jiang Yiyao , De Domenico Dario , Pan Chao
Published: December 2019

Various inerter systems utilizing velocity-dependent damping for vibration control have been developed. However, a velocity-dependent damping element may exhibit relatively poor performance compared to a displacement-dependent damping element (DDE) of equivalent damping ratio, when the structural deformation is small in the early stage of the seismic response. To address this issue, the advantage of DDE in generating a larger control force in the early stage of excitation is promoted here and enhanced by a supplemental inerter-spring-system, thus realizing a proposed novel displacement-dependent damping inerter system (DDIS). First, the influence of various DDIS-parameters is carried out by resorting to the stochastic linearization method to handle non-linear terms. Then, seismic responses of the DDIS-controlled system are evaluated in the time domain taking the non-linearity into account, thus validating the accuracy of the stochastic dynamic analysis. Several design cases are considered, all of which demonstrated damping enhancement and timely control achieved by the DDIS. The results show that the energy dissipation as well as reduction of structural displacement and acceleration accomplished by the proposed system are significant. DDIS suppresses structural responses in a timely manner, as soon as the peak excitation occurs. In addition, it is demonstrated that interactions among the inerter, spring, and DDE, which constitute the damping-enhancement mechanism, lead to a higher energy-dissipation efficiency compared to the DDE alone.
Effects of Solid Die Types in Complex and Large-Scale Aluminum Profile Extrusion
Authors: Truong Tat-Tai , Hsu Quang-Cherng , Tong Van-Canh
Published: December 2019

Increasing customer requirements for quality and productivity in extruding aluminum products has led to the development of different types of extrusion dies. In this study, three different types of dies, including traditional flat die, pocket die and spread die were designed to extrude complex and large-scale solid profiles. The design parameters for these dies were used from actual extrusion experience. The results obtained from steady-state simulation such as velocity, temperature, extrusion force, and die deformation were used to assess the advantages and disadvantages of the dies. Transient simulations were performed to analyze the evolution of transverse weld in the pocket and spread dies. The effects of ram speeds on the related extrusion parameters were also investigated. The research results provide useful guides for designers and engineers in selecting these types of extrusion dies.
Car Wake Flows and Ultrafine Particle Dispersion: From Experiments to Modelling
Authors: Murzyn Frédéric , Fokoua Georges , Rodriguez Romain , Shen Chenhao , Larrarte Frédérique , Mehel Amine
Published: December 2019

Improving air quality in urban environments and transportation systems is crucial. Concerns are related to health and environmental issues associated with huge costs. Car cabin is a microenvironment where pollutants can accumulate with possible risks for occupants. In automotive engineering, it has then become mandatory to study the path and dispersion of such pollutants emitted from the tailpipe of a car. In the present paper, the relation between the flow topology and the dispersion of ultrafine particles (UFP) in the wake of a vehicle is discussed. Experiments were undertaken at a reduced scale using simplified car models. Experimental conditions were defined to be representative of a vehicle in an urban environment. Based on experimental data, a simplified analytical model is developed, which aims at describing the concentration fields of UFP in the wake of a single vehicle for different rear slant angles. The strengths and limits of the present model are discussed and ways of improvements are suggested. Additional experiments are presented to assess the influence of the inter-vehicle distance on this recirculation region. Critical inter-vehicle distances were determined based on defined criteria for different rear slant angles of the leading vehicle and compared to safety clearances.