Evidence for Anisotropic Vortex Dynamics and Pauli Limitation in the Upper Critical Field of FeSe1-xTex

We have determined HC2(T) for FeSe1-xTex (x=0.52) single crystals using resistivity measurements at high static and pulsed magnetic field, as well as specific heat measurements up to 9T. We find that the significant anisotropy of the initial slope of HC2(T) determined from resistivity measurements, is not present when HC2 is determined from the specific heat results. This suggests that the thermodynamic upper critical field is almost isotropic, and that anisotropic vortex dynamics play a role. Further evidence of anisotropic vortex dynamics is found in the behaviour in pulsed field. We also find that Pauli limiting must be included in order to fit the temperature dependence of HC2, indicating probably higher effective mass in FeSe1-xTex than in other Fe superconductors

Manipulation of photoperiod in growth factors of beluga sturgeon Huso huso

The beluga sturgeon is considered as the most important species for caviar production. This study aimed to evaluate effects of photoperiod manipulation on growth factors of beluga sturgeon. The six photoperiod regimes (light: dark cycle) including natural photoperiod (control), 24L : 0D, 16L : 8D, 12L : 12D, 8L : 16D and 0L : 24D with the three replicates. The treatment 5 (8L: 16D) gained the greatest final weight (2194.4 g) after 73 rearing days and besides, the treatments 4, 3 and 1 (12L : 12D, 16L : 8D, and Control) can be considered as the good photoperiod regimes for beluga sturgeon. The continuous light (24L : 0D) and continuous dark (0L : 24D) significantly (P < 0.05) reduced the final weight of fish to 1804.2 g and 1976.1 g, respectively. Regulated photoperiod significantly improve growth rate and food conversion ratio of beluga sturgeon

Clinically stable very low birthweight infants are at risk for recurrent tissue glucose fluctuations even after fully established enteral nutrition

Objective: In previous cases, we have observed occasional hypoglycaemic episodes in preterm infants after initial intensive care. In this prospective study, we determined the frequency and severity of abnormal tissue glucose (TG) in clinically stable preterm infants on full enteral nutrition. Methods: Preterm infants born at <1000 g (n=23; G1) and birth weight 1000–1500 g (n=18; G2) were studied at a postmenstrual age of 32±2 weeks (G1) and 33±2 weeks (G2). Infants were fed two or three hourly, according to a standard bolus-nutrition protocol, and continuous subcutaneous glucose measurements were performed for 72 h. Normal glucose values were assumed at ≥2.5 mmol/L (45 mg/dL) and ≤8.3 mmol/L (150 mg/dL). Frequency, severity and duration of glucose values beyond normal values were determined. Results: We observed asymptomatic low TG values in 39% of infants in G1 and in 44% in G2. High TG values were detected in 83% in G1 and 61% in G2. Infants in G1 experienced prolonged and more severe low TG episodes, and also more frequent and severe high TG episodes. In G1 and G2, 87% and 67% of the infants, respectively, showed glucose fluctuations characterised by rapid glucose increase followed by a rapid glucose drop after feeds. In more mature infants, glucose fluctuations were less pronounced and less dependent on enteral feeds. Conclusions: Clinically stable well-developing preterm infants beyond their initial period of intensive care show interstitial glucose instabilities exceeding values as low as 2.5 mmol/L and as high as 8.3 mmol/L. This novel observation may play an important role for the susceptibility of these high-risk infants for the development of the metabolic syndrome

Predicting the stress-strain behaviour of zeolite-cemented sand based on the unconfined compression test using GMDH type neural network

Stabilizing sand with cement is considered to be one of the most cost-effective and useful methods of in-situ soil improvement, and the effectiveness is often assessed using unconfined compressive tests. In certain cases, zeolite and cement blends have been used; however, even though this is a fundamental issue that affects the settlement response of a soil, very few attempts have been made to assess the stress-strain behaviour of the improved soil. Also, the majority of previous studies that predicted the unconfined compressive strength (UCS) of zeolite cemented sand did not examine the effect of the soil improvement variables and strain concurrently. Therefore, in this paper, an initiative is taken to predict the relationships for the stress-strain behaviour of cemented and zeolite-cemented sand. The analysis is based on using the unconfined compression test results and Group Method of Data Handling (GMDH) type Neural Network (NN). To achieve this end, 216 stress-strain diagrams resulting from unconfined compression tests for different cement and zeolite contents, relative densities, and curing times are collected and modelled via GMDH type NN. In order to increase the accuracy of the predictions, the parameters associated with successive stress and strain increments are considered. The results show that the suggested two and three hidden layer models appropriately characterise the stress-strain variations to produce accurate results. Moreover, the UCS values derived from this method are much more accurate than those provided in previous approaches. Moreover, the UCS values derived from this method are much more accurate than those provided in previous approaches which simply proposed the UCS values based on the content of the chemical binders, compaction, and/or curing time, not considering the relationship between stress and strain. Finally, GMDH models can be considered to be a powerful method to determine the mechanical properties of a soil including the stre

Determination of the Fermi Velocity by Angle-dependent Periodic Orbit Resonance Measurements in the Organic Conductor alpha-(BEDT-TTF)2KHg(SCN)4

We report detailed angle-dependent studies of the microwave (f=50 to 90 GHz) interlayer magneto-electrodynamics of a single crystal sample of the organic charge-density-wave (CDW) conductor alpha-(BEDT-TTF)2KHg(SCN)4. Recently developed instrumentation enables both magnetic field (B) sweeps for a fixed sample orientation and, for the first time, angle sweeps at fixed f/B. We observe series' of resonant absorptions which we attribute to periodic orbit resonances (POR) - a phenomenon closely related to cyclotron resonance. The angle dependence of the POR indicate that they are associated with the low temperature quasi-one-dimensional (Q1D) Fermi surface (FS) of the title compound; indeed, all of the resonance peaks collapse beautifully onto a single set of f/B versus angle curves, generated using a semiclassical magneto-transport theory for a single Q1D FS. We show that Q1D POR measurements provide one of the most direct methods for determining the Fermi velocity, without any detailed assumptions concerning the bandstructure; our analysis yields an average value of v_F=6.5x10^4 m/s. Quantitative analysis of the POR harmonic content indicates that the Q1D FS is strongly corrugated. This is consistent with the assumption that the low-temperature FS derives from a reconstruction of the high temperature quasi-two-dimensional FS, caused by the CDW instability. Detailed analysis of the angle dependence of the POR yields parameters associated with the CDW superstructure which are consistent with published results. Finally, we address the issue as to whether or not the interlayer electrodynamics are coherent in the title compound.Comment: 28 pages, including 6 figures. Submitted to PR

Nyquist method for Wigner-Poisson quantum plasmas

By means of the Nyquist method, we investigate the linear stability of electrostatic waves in homogeneous equilibria of quantum plasmas described by the Wigner-Poisson system. We show that, unlike the classical Vlasov-Poisson system, the Wigner-Poisson case does not necessarily possess a Penrose functional determining its linear stability properties. The Nyquist method is then applied to a two-stream distribution, for which we obtain an exact, necessary and sufficient condition for linear stability, as well as to a bump-in-tail equilibrium.Comment: 6 figure

Numerical investigation of alpha Stirling engine performance based on ideal and actual adiabatic analysis

This article discusses in detail the adiabatic models investigations of alpha Stirling engine with study the influence of performance factors; adiabatic analysis is a crucially effective method because it is close to the real and practical engines when compared to isothermal analysis. The numerical model was created using MATLAB software, an extremely useful tool for solving equations. The study includes two adiabatic analysis models: the ideal model, which considers heat transfer is the duty of the heater and cooler when the regenerator is ideal, and the simple model, which considers the loss and the transfer of heat between the regenerator matrix and the working fluid. © Published under licence by IOP Publishing Ltd

Effect of preterm birth on growth and blood pressure in adulthood in the Pelotas 1993 cohort

Background Preterm birth has been associated with increased risk of hypertension and cardiovascular disease later in adulthood, attributed to cardiovascular and metabolic alterations in early life. However, there is paucity of evidence from low- and middle-income countries (LMICs). Methods We investigated the differences between preterm (<37 weeks gestational age) and term-born individuals in birth length and weight as well as adult (18 and 20 years) height, weight and blood pressure in the Brazilian 1993 Pelotas birth cohort using linear regressions. Analyses were adjusted for the maternal weight at the beginning of pregnancy and maternal education and family income at childbirth. Additional models were adjusted for body mass index (BMI) and birthweight. Separate analyses were run for males and females. The complete sample was analysed with an interaction term for sex. Results Of the 3585 babies included at birth, 3010 were followed up in adulthood at 22 years. Preterm participants had lower length and weight at birth. This difference remained for male participants in adulthood, but female participants were no shorter than their term counterparts by 18 years of age. At 22 years, females born preterm had lower blood pressures (systolic blood pressure −1.00 mmHg, 95%CI −2.7, 0.7 mmHg; diastolic blood pressure −1.1 mmHg, 95%CI −2.4, 0.3 mmHg) than females born at term. These differences were not found in male participants. Conclusions In this Brazilian cohort we found contrasting results regarding the association of preterm birth with blood pressure in young adulthood, which may be unique to an LMIC

Effect of preterm birth on growth and blood pressure in adulthood in the Pelotas 1993 cohort

BACKGROUND: Preterm birth has been associated with increased risk of hypertension and cardiovascular disease later in adulthood, attributed to cardiovascular and metabolic alterations in early life. However, there is paucity of evidence from low- and middle-income countries (LMICs). METHODS: We investigated the differences between preterm (<37 weeks gestational age) and term-born individuals in birth length and weight as well as adult (18 and 20 years) height, weight and blood pressure in the Brazilian 1993 Pelotas birth cohort using linear regressions. Analyses were adjusted for the maternal weight at the beginning of pregnancy and maternal education and family income at childbirth. Additional models were adjusted for body mass index (BMI) and birthweight. Separate analyses were run for males and females. The complete sample was analysed with an interaction term for sex. RESULTS: Of the 3585 babies included at birth, 3010 were followed up in adulthood at 22 years. Preterm participants had lower length and weight at birth. This difference remained for male participants in adulthood, but female participants were no shorter than their term counterparts by 18 years of age. At 22 years, females born preterm had lower blood pressures (systolic blood pressure -1.00 mmHg, 95%CI -2.7, 0.7 mmHg; diastolic blood pressure -1.1 mmHg, 95%CI -2.4, 0.3 mmHg) than females born at term. These differences were not found in male participants. CONCLUSIONS: In this Brazilian cohort we found contrasting results regarding the association of preterm birth with blood pressure in young adulthood, which may be unique to an LMIC

Analysis of Technical Efficiency, Economic Feasibility, and Environmental Impacts of using Solar Heating Installations for Buildings

This study aims to provide a clear vision of the potential of solar heating installations currently available in the market as a successful alternative to traditional methods, economic feasibility, and contribution to reducing greenhouse gas emissions. The study involves using solar energy to provide the energy needed to heat a house in Warsaw. The solar installations were tested, and their performance was simulated and compared based on production quantity with cost and suitability for the climatic conditions of the study area. In addition to determining the best way to install solar panels by calculating optimal tilt and azimuth angles. The work methodology for designing a suitable solar system went in two directions; the first is using a solar thermal collector in direct heat generation, while the second is using photovoltaic panels to generate electricity to heat water by a water heater. All results were obtained through simulation work in RETScreen and PVGIS software. The results showed that solar thermal collectors and photovoltaic panels contributed to the annual energy demand by 40% and 43%, and the financial returns in case the conventional energy is electricity or natural gas are 715 and 252 EUR (for STC) and 765 and 269 EUR (for PV), respectively. It also reduced annual emissions by 2.36 and 2.53 tCO2. © 2023, International Journal of Renewable Energy Research. All Rights Reserved.Ministry of Education and Science of the Russian Federation, Minobrnauka: FEUZ-2022-0031Funding from the Ministry of Science and Higher Education of the Russian Federation (Ural Federal University Program of Development within the Priority-2030 Program) is gratefully acknowledged: Grant Number FEUZ-2022-0031