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BackgroundThe transition to pulmonary respiration and the termination of foetal cardiovascular shunts is expected to commence immediately after birth. Subsequently, alveolar ventilation and tissue perfusion must be established, despite the challenge of extra-uterine environmental conditions, which could be quite demanding, even to the adult animals. The current study evaluated neonatal adjustment and diurnally induced changes in respiratory and pulse rates in kids of Red Sokoto, Sahel and West African Dwarf (WAD) goats in a tropical climate.ResultsMorning and afternoon respiratory rates started decreasing (P P P P P P P ConclusionIt was concluded that the afternoon rise in ambient temperature induced the establishment of a clear diurnal variation in respiratory rate 24 h postnatal, while the diurnal variation in pulse rate was weak and irregular. The tropical climate may be quite challenging to the attainment of physiological stability in respiratory and cardiovascular functions of neonatal goat kids, especially during the hot season.

Cemented paste backfill (CPB) has been extensively used in the mine industry to backfill underground mine cavities for ground support and/or tailings management. Once placed in mine underground cav...

SLM methods are widely used to manufacture metal parts for functional use in mainly automotive, aerospace and medical industries. Besides many advantages of SLM, manufacturing times take long times and need many costs. In this study, nine samples were manufactured at the same time to set a scenario of multiple samples manufacturing and providing highly productive conditions. Some manufacturing problems such as internal stresses and dimensional distortions occurred during manufacturing. These problems were the result of heterogeneous temperature gradients and geometrical properties. FEA studies were carried out by “Netfabb Ultimate Simulation LT 2019”. Temperature changes were observed, and relations among these temperature changes, residual stresses, as well as dimensional distortions were evaluated. As a result, the orientation distance of samples was an important parameter due to residual stress and displacement. Unsuitable positioning distance between samples caused high dimensional distortion, macro cracks and residual stress. The plastic strain equation was correlated according to the results of the analysis with 7% difference (regression) to define the optimum distance between parts.

In this work, solar-heating-induced temperature-based photocatalytic hydrogen evolution reaction (PC-HER) of different photocatalysts (TiO2 P25, g-C3N4, and their loaded Pt) was comprehensively stu...

Lead zirconate-lanthanum magnesium niobate (Pb(1-x)Laх[Zr(1-x)Mg2х/3Nbх/3]O3) solid solutions with x up to 10 mol.% have been obtained by solid phase synthesis method. It has been found that solid ...

The temperature-dependent structure and properties of a liquid GaInSn eutectic alloy have been investigated by using in situ high-energy X-ray diffraction, thermal expansion, and heat capacity meas...

The structures of the equiatomic stannides RERhSn with the smaller rare earth elements Y, Gd-Tm and Lu were reinvestigated on the basis of temperature-dependent single crystal X-ray diffraction data. GdRhSn crystallizes with the aristotype ZrNiAl at 293 and 90 K. For RE = Y, Tb, Ho and Er the HP-CeRuSn type (approximant with space group R3m) is already formed at room temperature, while DyRhSn adopts the HP-CeRuSn type below 280 K. TmRhSn and LuRhSn show incommensurate modulated variants with superspace groups P31m(1/3; 1/3; γ) 000 (No. 157.1.23.1) (γ = 3/8 for TmRhSn and γ = 2/5 for LuRhSn). The driving force for superstructure formation (modulation) is a strengthening of Rh–Sn bonding. The modulation is expressed in a 119Sn Mössbauer spectrum of DyRhSn at 78 K through line broadening.

Application of cold storage temperatures below optimum induces a high risk and threat of chilling injury (CI) in the case of sensitive commodities. Sweet pepper belongs to this group of vegetables, so our main objective was to investigate and monitor the effect of non-optimal temperatures (2.5 and 5 °C) induced stress (chilling injury) on kápia type sweet pepper (Capsicum annuum L.) during its postharvest storage by nondestructive quality measuring methods. Fresh, semi-matured (reddish-green colored) samples of ‘Kapitány F1’ cultivar were stored at 2.5, 5 and 10 °C for 7 d followed by 7 d shelf-life. Nondestructive texture measurements were carried out by a purpose built tabletop acoustic stiffness device. Surface color and chlorophyll content related quality indices were evaluated by a chroma meter, a DA-meter® and a chlorophyll fluorescence imaging system. High resolution digital pictures were captured and analyzed for possible CI defects by means of surface color values (normalized RGB, hue and saturation). According to our results, the evaluated quality indices (DA-index®, acoustic stiffness coefficient, surface color parameters; F0, Fm, Fv and Fv/Fm chlorophyll fluorescence parameters) clearly represented the temperature dependent quality changes during low temperature storage, subsequently followed by ambient shelf-life. Samples stored under and at 5 °C showed the chilling temperature stressed symptoms of delayed and partly retarded postharvest ripening, even under simulated shelf-life conditions, but without the onset and manifestation of the characteristic visible symptoms of chilling injury. This may raise doubts and suggest possible future research areas regarding the role of non-optimal cold storage temperatures induced stress, the effect of chilling injury contributing factors and consequences.

Wheat growth has been severely affected by increases in global temperature. The Eastern Indo-Gangetic Plains of India face similar constraints due to the traditional wheat–rice cropping system where wheat planting is often delayed leading to high temperature induced terminal heat stress. Grain characters like grain length, width, area along with starch synthesis are affected severely during heat stress. Considering the importance of grain traits, we screened the response of 55 wheat genotypes under terminal heat stress conditions to ten grain characteristics. We found that the means of all the grain traits were reduced in heat stress conditions. The effect of heat stress shows a significantly reduced grain width and perimeter, but the extent of damage is less on different grain starch characteristics e.g., grain starch area (GSA), grain starch length (GSL) and grain starch volume (GSV). Stepwise multiple regression analysis revealed that grain starch area and grain volume are the best predictors of yield under optimum sowing date conditions whereas, grain width is the best predictor under late sowing date conditions. Interrelationship studies among ten grain characters showed that the genotypes with higher levels of grain starch characteristics (GSA, GSL and GSV) in combination with the five grain size characters (grain length, grain width, grain perimeter, grain area, A/B-type starch granules) under late sowing date conditions should be promoted for the cultivation of wheat in heat stress prone areas. The present study identified and recommends some heat tolerant wheat genotypes in terms of higher yield and grain starch characteristics namely, CRPW-33, CRPW-17, CRPW-12, CRPW-126 and CRPW-21.

Thirteen genotypes of Pearl millet (Pennisetum glaucum (L.) R. Br.) selected on the basis of heat tolerance were studied to see changes at biochemical and physiological levels. The plants were initially raised under normal condition in small plastic pots and 20 days old seedling were exposed at (40 °C for 4 hrs, 44 °C for 4 hrs and 46 °C for 2 hrs) in BOD incubator at Mandor to create the heat stress condition. After two days treatment data were recorded for MSI, chlorophyll content, antioxidative enzymes and MDA content. MSI, chlorophyll content and MDA decreased significantly due to heat stress while SOD, and CAT increased significantly under heat stress condition. The genotypic difference was also found significant. In some genotypes R/S increased while in some genotypes R/S ratio decreased under heat stress. The genotypes and PPMI 1053 and PPMI 1087 and HB 17-6 perform better having antioxidative enzymes. The better performance of these genotypes may be due to high RWC, MSI, chlorophyll, SOD, CAT and low MDA content under high temperature stress.

Stable colloidal zein nanoparticles (NPs) were synthesized by using controlled precipitation method. They were made fluorescence active by incorporating a small amount of fluorescence quinolinium surfactant. The incorporation of fluorescence surfactant provided both the colloidal stability and the fluorescence ability to determine the phase transition in zein NPs under the effect of temperature variation. Maintaining colloidal stability under the effect of temperature variation is an essential aspect of zein NPs applicability as a source of vegetarian protein supplement in different food suspensions. Different techniques such as fluorescence, DLS size, zeta potential, and FTIR measurements were applied to determine the influence of temperature on the colloidal stability of zein NPs. Zein NPs undergo phase transition well above room temperature while maintaining their size in nanometer range, and the phase transition temperature decreased with the amount of zein used in the synthesis of zein NPs. The results highlighted the potential use of zein NPs as a vegetarian supplement protein in different food products.

SummaryThe effects of temperature on the permeability coefficients of carbonaceous shales and the underlying mechanisms have been investigated experimentally. Pressure-pulse-decay gas-permeability tests were performed on seven shale plugs with different lithological compositions, organic-matter contents ranging from 0.8 to 11.7% total organic carbon (TOC) and thermal maturity between 0.53 and 1.45% random vitrinite reflectance (VRr). During the tests, the measuring temperatures were changed stepwise from 30 to 120°C and back to 30°C while axial load and confining pressure were kept constant. Sister plugs were used for mechanical tests to investigate the creep response upon thermal loading under the same temperature conditions. The samples showed varying degrees of permeability reduction by up to 71% with increasing temperature. This reduced permeability persisted during the cooling phase. The observed permeability changes reflect the elastoplastic deformation upon the thermal compaction of the rocks. Permeability reduction and creep response with increasing temperature are evidently controlled by organic matter, although clay minerals also played an important role. Organic-matter- and clay-rich shales exhibit the strongest response to temperature, while temperature effects were slightly smaller for overmature samples. Rock mechanical analysis showed that permeability reduction correlates with temperature-related creep/deformation of the shales. Given the strong temperature dependence of the mechanical stiffness of solid organic matter and of the viscosity of bituminous solids/liquids, more attention should be paid to temperature effects in the assessment of shale permeability. Our experimental results document that thermal stimulation has negative effects on shale-transport properties and that measurements conducted at laboratory temperatures can lead to substantial overestimation of in-situ shale permeability.

Background The present study attempted to demonstrate how the configuration of hydrogel-coated coils is influenced by different temperature exposures. Thirty detachable hydrogel-coated coils were evaluated in an in vitro water immersion test under five different temperature ranges (22.6 °C, 37 °C, 40–50 °C, 50–60 °C, and 60–70 °C). The configuration changes were classified (configuration I, configuration II, and configuration III) according to the curling that occurred during 30 min of immersion. Configuration stability of five Hydrogel-coated coils was also evaluated in a two-step temperature immersion test. Results All hydrogel-coated coils showed some configuration changes during water immersion. However, a logarithmic transformation of the time and temperature data showed a significant (p R = 0.97, configuration II: R = 0.98, configuration III: R = 0.97). The time needed to reach configuration III (complete coiling) was 160.4 ± 41.9 s at 37.5 °C (range: 100–205 s), 45.7 ± 22.2 s at 47.5 °C (range: 23–70 s), 20.2 ± 7.2 s at 57.5 °C (range: 14–32 s), and 10.3 ± 2.4 s at 67.5 °C (range: 7–13 s). Conclusions Temperatures above 55 °C induced immediate configurational changes in the hydro-coated coils, achieving complete curling within less than 30 s. Temperatures near 36 °C (normal body temperature) require more time to reach optimal coil curling (configuration III). The optimization of HydroCoil preparation can reduce interventional procedural time and improve clinical results.

A termografia infravermelha (TIV) representa um exame de imagem complementar, trata-se de uma ferramenta não ionizante e não invasiva que capta e registra a emissão térmica da superfície da pele. Esta vem sendo utilizada na medicina humana há mais de 50 anos, na avaliação das mudanças da temperatura superficial induzida por enfermidades como: neoplasias mamárias, diabetes, distúrbios vasculares, regiões musculares, doenças articulares, alterações simpáticas e parassimpáticas entre outras utilidades. Em medicina veterinária, as TIV primeiras descrições ocorreram na década de 1960, e desde então passou a crescer tecnologicamente. Esta revisão descreveu sobre a princípios básicos e as principais aplicações da TIV em medicina veterinária. Foi realizada uma pesquisa bibliográfica possibilitando assim consolidar informações relativas à base teórica e ao tema proposto. Após a revisão foi possível identificar a história tecnológica da TIV, além de descrever princípios físicos básicos relacionados a técnica e as principais aplicações em medicina veterinária, visando destacar a eficácia desta modalidade no auxilio diagnóstico das inúmeras situações descritas.

Heterointerfaces coupling complex oxides exhibit coexisting functional properties such as magnetism, superconductivity, and ferroelectricity, often absent in their individual constituent. SrTiO3 (STO), a canonical band insulator, is an active constituent of such heterointerfaces. Temperature-, strain-, or mechanical stress-induced ferroelastic transition leads to the formation of narrow domains and domain walls in STO. Such ferroelastic domain walls have been studied using imaging or transport techniques and, often, the findings are influenced by the choice and interaction of the electrodes with STO. In this work, we use graphene as a unique platform to unveil the movement of oxygen vacancies and ferroelastic domain walls near the STO surface by studying the temperature and gate bias dependence of charge transport in graphene. By sweeping the back gate voltage, we observe antihysteresis in graphene typically observed in conventional ferroelectric oxides. Interestingly, we find features in antihysteresis that are related to the movement of domain walls and of oxygen vacancies in STO. We ascertain this by analyzing the time dependence of the graphene square resistance at different temperatures and gate bias. Density functional calculations estimate the surface polarization and formation energies of layer-dependent oxygen vacancies in STO. This corroborates quantitatively with the activation energies determined from the temperature dependence of the graphene square resistance. Introduction of a hexagonal boron nitride (hBN) layer, of varying thicknesses, between graphene and STO leads to a gradual disappearance of the observed features, implying the influence of the domain walls onto the potential landscape in graphene.

Poly(N-vinylcaprolactam) (PNVCL) polymers are stimuli-responsive and change their conformation in aqueous solutions upon changes in salt concentration, concentration of organic solvents, or temperature, making these molecules highly interesting for tailored release of drugs or fabrication of sensors or actuators. At lower critical solution temperature (LCST), PNVCL chains undergo a transition from a coil to a globule and become insoluble. In contrast to other polymers, however, PNVCL has received much less attention as to elucidating driving forces of its coil-to-globule transition at an atomistic level. Here, we show by a combined computational and experimental study that upon temperature increase, PNVCL chains dissolved in water experience an increase of intramolecular interactions between C3 and C4 of the caprolactam ring. Therefore, more favorable cavity formation energies and the increase of intramolecular interactions outweigh the loss in polar and hydrophobic solvation, and the loss of configurational entropy in the coil-to-globule transition and, thus, may be considered driving forces of the polymer’s collapse at LCST. These results are based on molecular dynamics simulations of in total 600 μs length and transition (free) energy computations that have been validated internally and against experimental data. We systematically tested the influence of the polymer’s length, concentration, tacticity, of the thermodynamic ensemble, and of the water model. Tacticity was found to be most influential, with atactic polymers showing the strongest tendency to collapse. The presented approach should be applicable to scrutinize at the atomistic level the impact of, for example, ion and polymer dispersity on the coil-to-globule transition of PNVCL, and the LCST behavior of other polymers.

The effect of light- and elevated temperature-induced degradation (LeTID) can be nonpermanently reversed by charge carrier injection below the degradation temperature (commonly used degradation temperatures are above ~70 °C). In this study, we show that the rate of temporary recovery depends strongly on the excess carrier density. We observe that the order of the reaction changes from pseudo-zero to first with increasing injection. The rate decreases slightly with increasing temperature. Since the samples can go through multiple degradation/recovery cycles without distinct changes in the degradation kinetics, the experimentally accessible recovered and degraded states are interpreted as manifestations of the equilibrium concentrations of the defect responsible for LeTID at different temperatures. Based on our observations, we argue that the process underlying LeTID degradation is the dissociation of a precursor rather than an association of two or more components. In light of the relation between LeTID susceptibility and bulk hydrogen concentration, we hypothesize that the LeTID precursor dissociates into the LeTID defect and monatomic hydrogen. Numerical simulations of the coupled rate equations including hydrogen interactions well reproduce the experimental observations; according to these results, the presence of a sink for the atomic hydrogen such as dopant atoms is paramount for the LeTID degradation.

Highly accurate high-throughput experimentation (HTE) data for a set of 21 silicon-bridged C2-symmetric ansa-zirconocenes in propene homopolymerization were collected and were used to develop quant...

Adsorption of polycyclic aromatic hydrocarbons (PAHs) on mineral surfaces plays an important role in many engineering fields, such as oil recovery and oil sands production. In this work, the adsorp...

Objective The aim of this study was to test whether increased energy expenditure (EE), independent of physical activity, reduces acute diet-induced weight gain through tighter coupling of energy intake to energy demand and enhanced metabolic adaptations. Methods Indirect calorimetry and quantitative magnetic resonance imaging were used to assess energy metabolism and body composition during 7-day high-fat/high-sucrose (HFHS) feeding in male and female mice housed at divergent temperatures (20°C vs. 30°C). Results As previously observed, 30°C housing resulted in lower total EE and energy intake compared with 20°C mice regardless of sex. Interestingly, housing temperature did not impact HFHS-induced weight gain in females, whereas 30°C male mice gained more weight than 20°C males. Energy intake coupling to EE during HFHS feeding was greater in 20°C versus 30°C housing, with females greater at both temperatures. Fat mass gain was greater in 30°C mice compared with 20°C mice, whereas females gained less fat mass than males. Strikingly, female 20°C mice gained considerably more fat-free mass than 30°C mice. Reduced fat mass gain was associated with greater metabolic flexibility to HFHS, whereas fat-free mass gain was associated with diet-induced adaptive thermogenesis. Conclusions These data reveal that EE and sex interact to impact energy homeostasis and metabolic adaptation to acute HFHS feeding, altering weight gain and body composition change.

The interaction between bending and shear effects in steel beams can be amplified under fire conditions due to rapid degradation in strength and stiffness properties of steel, together with temperature-induced local instability effects. This paper presents temperature-induced moment-shear (M-V) interaction phenomenon in compact (Class 1) steel beams. Results generated from numerical studies are utilized to quantify the effects of temperature-induced critical parameters influencing moment-shear interaction, shear and flexural sectional capacity, as well as instability in steel beams under fire conditions. The major findings of this work are two folds: (1) occurrence of temperature-induced instability adversely reduces shear capacity, as compared to flexural capacity, and (2) this rapid degradation in shear capacity trigger moment–shear interaction phenomenon at elevated temperatures. Eventually, this shifts failure mode in steel beams towards a shear dominant failure mechanism on the interaction envelope.

The effect of storage conditions on changes of pH, total soluble solids (°Brix), colour, betalains (betacyanins and betaxanthins), and 5-hydroxymethylfurfural was investigated in apple-beetroot juices stored at 2, 7 and 20 °C for 120 days. The results obtained showed that the quality of apple-beetroot juice is significantly influenced by temperature and storage duration. Increasing storage time and temperature induced an apparent rise (P

The study is concerned with structural rearrangements in the crystals of heterospin complexes Cu(hfac)2 with nitroxide radicals LR (hfac is hexafluoroacetylacetonate, LR is 2-(1-R-1H-pyrazol-4-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl, R is Et or Allyl) induced by increasing pressure from 10−4 to ∼1 GPa in the pressure-transmitting medium. An increase in the external pressure to only ∼0.03 GPa leads to the disappearance of the temperature-induced magnetic anomaly observed for these heterospin crystals under ambient conditions.

Higher temperatures associated with climate change often increase the severity of plant diseases. An understanding of how plants respond to pathogens during high temperature stress is required for crop improvement, but the molecular mechanisms underlying this response are largely unknown. Mechanistic research has primarily focused on plant responses during either single stresses or heat-induced loss of single gene resistance. Transcriptome analyses of plant responses to a single stress compared to combined-stresses reveal significant differences showing that single-stress response studies are inadequate for determining the mechanisms of high temperature-induced disease susceptibility. To combat plant disease in light of climate change, future research will require comprehensive study designs and analyses.

The thermophysical data of fruit is vital to the study and optimization of postharvest handling processes. However, data available in the literature are not always consistent and must not be used directly. It is crucial to examine the accuracy and reliability of the property data. Also, models to predict the thermal properties of fruit are not distinctly identified and included in the list of models for food materials. The aim of this review is to show the gaps in fruit properties data with emphasis on those properties that are important during postharvest handling. This paper also presents a review of the measurement and prediction techniques for the thermophysical properties of fruit. Fruit thermophysical properties vary with temperature, moisture content, cultivar, and even between the various parts of the same product. The presented review is a valuable input for developing mathematical models that predict cooling rate, cooling time, cooling uniformity and refrigeration energy usage during postharvest handling processes (e.g. precooling and cold storage), as well as for applications related to prediction and monitoring of temperature induced fruit quality changes.

We present a detailed case study of degradation in monocrystalline silicon photovoltaic modules operating in a utility-scale power plant over the course of approximately three years. We present the results of degradation analysis on arrays within the site, and find that five of the six arrays degraded faster than the best performing array, even though the arrays consist of modules of the same manufacturer and model. We also describe the results of extensive laboratory characterization of modules returned from the field, including module- and cell-level current–voltage characterization, luminescence imaging, and accelerated testing. The laboratory test results and the field performance are consistent with light and elevated temperature induced degradation (LeTID). Notably, we observe differences in back contact technology between affected and unaffected modules. This article also demonstrates a method to identify possible LeTID degradation in the field and confirm the result with laboratory testing of a small number of modules.

We have studied lifetime instabilities in p -type boron-doped mono-like silicon during light soaking (LS) and dark annealing (DA) at different temperatures, and their behavior upon LS/DA cycling at various degradation and regeneration stages. Despite having similar capture cross section ratios, it is found that the defects responsible for the degradation under illumination and in the dark could stem from two separate reactions, with hydrogen being the common precursor. A model for light and elevated temperature induced degradation (LeTID) is presented based on our experimental findings. It is proposed that hydrogen atoms originally bound in the silicon nitride layer are released into the silicon bulk above a certain firing temperature, which then interact with some other species in the silicon bulk under illumination, causing the LeTID degradation. During the cooling ramp of the firing process or extended DA, hydrogen in the silicon bulk starts to effuse into the ambient, reducing the amount of hydrogen remaining in the silicon bulk, and correspondingly affecting their LeTID behavior. The proposed model provides new insights to help understand complex LeTID behaviors reported in the literature, including its dependence on the firing profile, sample thickness, dopant type, and DA pretreatment.

The precise structure of nanocrystal (NC) solids is a delicate balance between energetic and entropic interactions. Studying the temperature-dependent structure of NC solids can inform understandin...

In this study, the effects of the single and multiple productions of samples by additive manufacturing on residual stress and displacement (distortions) were investigated. The samples were manufactured by Selective Laser Melting (SLM) machine using Ti6Al4V powders. Each time a different number (1, 5 and 13 samples) of cubic shaped samples were produced on the building platform. During the process, samples were observed with a thermal camera first, in order to understand the relationship amongst the residual stress, displacement and temperature gradients. Then, displacement values were measured experimentally with Coordinate Measurement Machine (CMM) device. Next, both displacement and residual stresses were calculated via Finite Element Analysis (FEA) method. Finally, residual stresses and displacement equations were determined by genetic expressional programming (GEP) using the results and data obtained from the tests and FEA. According to the results, the regression values of residual stress and displacement equation were found to be 0.96% and 0.88%, respectively. As the number of manufactured samples on the same platform increased, temperatures and irregular temperature distribution were increased.