Average Perimeter Research Articles

In Vitro Gene Conservation Status and the Quality of the Genetic Resources of Native Hungarian Sheep Breeds.

Studies revealed a global loss of genetic resources for local sheep breeds. Therefore, the current study aimed to introduce and highlight the progress made on Hungary's existing gene conservation program (small Gene Bank). Furthermore, we evaluated breed (Tsigai, Cikta, and Racka), season, and individual variabilities (n = 24) of the pre-freeze and post-thaw semen stored in the Gene Bank to enhance the gene conservation of the breeds. The samples were cryopreserved manually, and post-thaw spermatozoa were analyzed for motility (CASA), viability, chromatin structure, and morphometry of the sperm nuclei. Ejaculate volume, spermatozoa concentration, subjective motility and standard motility, kinematic parameters, and spermatozoa's head area standard deviation of the post-thaw samples differed significantly among breeds (p < 0.05). Season affected ejaculate volume, total spermatozoa number/ejaculate, STR, BCF, and ALH. We observed a significant (p < 0.001; 0.05) breed and season interaction on concentration, total spermatozoa number/ejaculate, VCL, LIN, WOB, spermatozoa's head average perimeter and nucleus length (Tsigai and Cikta differed but were statistically the same as Racka). Similarly, season significantly (p < 0.05) affected the proportion of ejaculate suitable for freezing. There was a significant (p < 0.05) difference in kinematic parameters and viability among the rams across the breeds. The spermatozoa's head morphometry of the Tsigai and Cikta breeds differed significantly (p < 0.05) among the rams. There were individual and breed differences in many spermatozoa quality parameters. The stored samples are of good quality, with more than 40% having intact membranes and low abnormal chromatin condensation.

Разработка СВЧ-установки для термообработки отходов убоя животных

Every day, the Russian Federation processes 126.3 tons of animal slaughter waste into animal feed. With an installation capacity of 35 kg/h, the required quantity is 7000 units. As a rule, the devices are energy-intensive. The problem is to reduce the operating costs of heat treatment of raw materials while maintaining the feed quality. The article introduces a new installation powered by an electrically driven resonator with rationalized operating modes. The research featured mucous by-products that require thermal treatment to neutralize the smell and disinfect the raw material. The authors investigated the dynamics of heating and used the data obtained to develop a digital installation model and test the electrodynamics in the resonator. After that, they rationalized the operating modes, i.e., corona discharge, electric field, screen efficiency, generator power, installation performance, and energy costs. The complex action of electromagnetic radiation provided a continuous combined heat treatment, disinfection, and odor neutralization with reduced operating costs. The electrical resonator was coaxially located in the shielding and contained a coronating electrode, electric bactericidal UV gas discharge lamps, knives, screws, and emitters from air-cooled magnetrons. The annular volume between the resonator and the coat excited the traveling wave by electromagnetic radiation through the perforation. Its average perimeter was a multiple of half the wavelength. The heat treatment with disinfection and fat rendering required an intrinsic quality factor of 8000, a generator power of 4.4 kW, a productivity of 35–40 kg/h, and energy costs of 0.25–0.28 kWh/kg. When the electric field was 5 kV/cm and the corona discharge was 9.79 kV/cm, the corona of bactericidal lamps provided the required ozone concentration and the bacterial contamination fell down to an acceptable level. The new installation with an electrical resonator reduced operating costs for heat treatment of animal slaughter waste and maintained the high-quality of the resulting feed products.

FLAW DEFECTION ANALYSE OF THE SURFACE OF ACRYLIC BASE PLASTICS

This study examines the possibility of assessing the quality of removable orthopedic devices by measuring the smoothness of their surfaces and detecting microscopic defects. The methodology involves comparing standard samples of the base material with samples that have been intentionally defective, using defectoscopy techniques for analysis. Initially, twenty samples of basic acrylic plastic were selected: half of them were perfectly machined to dental standards and the other half were intentionally scratched with sandpaper. These samples were then examined by macrophotography and analyzed using Image J software for quantitative image measurement. This analysis provided numerical data on the polished surface's quality, focusing on metrics such as the total number of defects, and the average size and perimeter of these defects. Statistical evaluation through the JUSP program compared the two sets of samples, highlighting significant differences between them. From the most prominent data points provided by Image J, conclusions were made regarding the surface quality of the acrylic plastic and how it is affected by specific mechanical imperfections. This method of using optical flaw detection offers a new way to clinically evaluate the quality of detachable orthopedic devices (like base plastic) in terms of their susceptibility to bacterial buildup, which could lead to inflammation in the prosthetic bed's mucosal lining. The use of flaw detection analysis allows for a general assessment of the quality of the material surface polishing, detection of surface defects in its structure that may occur during the production stage or during operation, thereby preventing areas of biofilm accumulation. Light-optical flaw detection in the experiment proved its effectiveness and makes us pay attention to the prospects of its improvement and wider implementation in clinical practice.

Prediction of Nili-Ravi buffalo bull fertility through Fourier harmonic analysis of sperm

Fourier harmonic analysis (FHA) is a robust method for identification of minute changes in sperm nuclear shape that are indicative of reduced fertility. The current study was designed to develop a fertility prediction model for Nili-Ravi buffalo bulls through FHA of sperm. In experiment I, FHA technique was standardized, average sperm nuclear perimeter was measured and sperm nuclear shape plot of buffalo bull was constructed. Sperm of buffalo bulls (n = 10) were stained with YOYO-1 and Hoechst-33342 to differentiate live and dead, and digital images were captured using phase contrast and fluorescent microscopy. The images were analyzed by ImageJ software and 100 sperm/bull were evaluated. The results are described as mean ± SEM values of mean harmonic amplitude (mharm), skewness harmonic amplitude (skharm), kurtosis harmonic amplitude (kurharm) and variance harmonic amplitude (varharm) at Fourier frequencies 0–5 along with the cartesian and polar coordinate plots of buffalo bull sperm. In experiment II, a fertility prediction model was developed based on FHA of buffalo bull sperm. Semen samples of low (n = 6), medium (n = 3) and high (n = 8) fertility bulls were investigated for FHA of sperm and harmonic amplitudes (HA) were generated. Firstly, to determine if live and dead sperm population have unique nuclear shape distribution; the mean, skewness, kurtosis and variance HA 0–5 of 1700 live and 1294 dead spermatozoa of 17 bulls were evaluated. T-test signified a difference in the mharm0 (2.363 ± 0.01 vs. 2.439 ± 0.02), skharm0 (−0.0002 ± 0.07 vs. −0.266 ± 0.09), kurharm0 (−0.156 ± 0.07 vs. 0.260 ± 0.18), kurharm2 (0.142 ± 0.11 vs. 1.031 ± 0.32) and varharm4 (0.109 ± 0.00 vs. 0.082 ± 0.00) of live vs. dead sperm population (p < 0.05). Therefore, 100 live sperm/bull were further evaluated for mean, skewness, kurtosis and variance HA 0–5 values among high (n = 6) and low-fertility (n = 6) groups. Results of T-test showed higher values of mharm2 (0.739 ± 0.01 vs. 0.686 ± 0.00), mharm4 (0.105 ± 0.001 vs. 0.007 ± 0.001), and skharm0 (0.214 ± 0.109 vs. −0.244 ± 0.097) in high vs. low-fertility group (p < 0.05). In next step, five significantly different combinations of discriminant measures between high and low-fertility groups were obtained by discriminant analysis. In conclusion, mharm4, skharm0 and varharm2 correctly identified 91.7 % of bulls into their respective fertility groups, and upon cross validation the value of the canonical correlation was 0.928.

ANALYSIS OF SURFACE QUALITY IN BASE ACRYLIC PLASTIC USING FLAW DETECTION METHOD

Before scanning the surface of the base acrylic plastic, ten samples were selected with a surface that had undergone all stages of finishing according to the proper dental protocol and ten samples that had previously been artificially damaged with scratches using sandpaper. This study addresses the assessment of the quality of removable orthopedic appliances concerning surface polishing and detection of microdefects. The research employs a comparative analysis of reference samples of base plastic and artificially damaged samples using flaw detection analysis. Prior to scanning the surface of the base acrylic plastic, ten samples underwent all stages of finishing according to dental protocol, while another ten samples were intentionally damaged with scratches using sandpaper. The macrophotographs obtained were processed using the "Image J" program, allowing for quantitative analysis of images, enabling the evaluation of surface quality through various parameters. This included evaluating the total number of defects, as well as the average area and perimeter of the defects. Statistical analysis conducted in the JUSP program enabled comparison between the two groups of samples, identifying significant quantitative differences. Based on the prominent indicators available in the Image J program, conclusions were drawn regarding the quality of the acrylic plastic surface and the factors influencing its condition through specific mechanical defects. The proposed method of light-optical flaw detection expands the clinical assessment capabilities of removable orthopedic structures (base plastic), particularly concerning potential bacterial contamination, which can serve as a significant factor in the formation of inflammation foci on the mucous membrane of the denture-supporting oral tissues. Flaw detection analysis enables a comprehensive assessment of material surface polishing quality and the detection of surface defects that may arise during production or use, thus preventing biofilm accumulation. The experiment demonstrated the effectiveness of light-optical flaw detection and highlights the potential for its further improvement and broader implementation in clinical practice.

Microstructural Approach Application for Morphological Change Determinations of Grapes during Drying

Grape dehydration is practiced widely in the food industry with large yields of sultanas produced globally. This paper proposes an investigation into the microstructure changes of grapes as they are dried by imaging specimens at intervals during dehydration at two temperatures using scanning electron microscopy. Two main methods were developed to obtain the complex boundaries of cells present in grape tissue in over 36 SEM images. Segmentation of the binary image using an adapted watershed function obtained the most consistent and accurate morphological shape. This was compared to a secondary method which used Canny’s edge detection function, morphological closing and skeletonizing to outline the cellular microstructure. MATLAB was utilised to convert these boundaries into measurable areas so that quantitative data on average cell area, perimeter and cell axis lengths were acquired. It was found that over the drying time, the cell area and perimeter were reduced as expected. Some variability in the data was clear due to only single samples being analysed for each temperature and time combination. Trends in cell perimeter, diameter and shape will be used to demonstrate relationships between morphological structure, drying temperature, and duration. Detailed images of the microstructure were obtained, and a unique image processing algorithm was developed to quantitatively analyse the properties of this microstructure. The development of automatic image processing techniques and algorithms will enable quantitative data to be extracted from any image and extend to any plant/food material.

Microwave device for heat treatment of meat by-products and waste

BACKGROUND: In the conditions of farms, there is a problem of neutralizing unpleasant odors during heat treatment of secondary meat raw materials to preserve the consumer properties of protein feed at low operating costs. AIM: Development of the device for heat treatment with disinfection and neutralization of the unpleasant odor of crushed secondary meat raw materials with the integral effect of an ultra−high frequency electromagnetic field, a bactericidal flow of UV rays and ozone in a continuous mode with electromagnetic safety ensured. METHODS: The raw materials are the stomach chambers of ruminants. The basic idea, principle of operation and design of the device are based on the propagation of microwave oscillations in a resonator with a spiral decelerating system. The microwave device contains a non-ferromagnetic cylinder with a perforated lower base, a coaxially arranged non-ferromagnetic spiral cylinder and an electrically driven fluoroplastic auger with a solid screw surface. The average perimeter of the annular volume, between the cylinder and the spiral cylinder forming the coaxial resonator, and its height are multiples of half-wavelength. Corona brushes are mounted to the annular base of the cylinder, under which electric gas discharge lamps powered by 1 kHz frequency generators are radially located, and a ceramic annular spherical surface is located under the lamps. Magnetrons are mounted along the perimeter of the outer cylinder with a shift of 120 degrees. The crackling is removed using a pneumatic conveyor. RESULTS: The feature of the coaxial resonator is that the inner core is formed as a spiral decelerating system. Therefore, the intrinsic Q-factor of the resonator is high, about 115000, therefore, the expected thermal efficiency is 0.7–0.75. The factor of dielectric losses of raw materials with a decrease in humidity from 76% to 30% is reduced by five times. Thus, while keeping the electric stress at the level of 1.2–2 kV/cm, the electromagnetic field power dissipated in a unit of the volume of the crackling decreases by five times, from 34 500 to 6800 W/cm3. CONCLUSIONS: A new design solution with a spiral coaxial resonator, the use of a ceramic reflector, and a number of physical factors made it possible to develop the design of the operation chamber for the heat treatment of ruminant slaughter waste with the neutralization of unpleasant odors with a capacity of 30–35 kg/h and specific energy costs of 0.16–0.19 kWh/kg.

Atributos das árvores hospedeiras, e não a diversidade da comunidade, conduzem a abundância de epífitas em florestas tropicais sazonais

Abstract Epiphytes are considered indicators of forest ecological integrity, but the factors that explain their abundance are still not well understood. We here evaluated tree colonization by epiphytes in old-growth monospecific reforestation stands of Astronium urundeuva (M.Allemão) Engl. (Anacardiaceae) and Eucalyptus saligna Sm. (Myrtaceae), in comparison to a neighbor seasonal tropical forest fragment under similar environmental conditions. In each forest type, we identified and measured all trees (planted and colonizers) from 5-cm stem diameter in five 200 m² plots and quantified all vascular epiphytes per tree. Tree species were categorized by bark roughness, canopy deciduousness and growth rate. The abundance of epiphytes and the frequency of host trees were higher in the A. urundeuva plantation than in the native forest, with the E. saligna stand in an intermediate position. Also, we found that host traits influenced the abundance of epiphytes in their trunks. Host trees had average stem perimeter and height both higher than non-hosts, which indicates that colonization is more likely to occur in older trees. The average abundance of epiphytes per tree was higher in species with rough bark, but no relationship was found with canopy deciduousness or tree growth rate. We evidenced, therefore, that forest plantations, even if monospecific, can provide habitat for epiphytes. However, at community level, colonization success, either in native or restored forest, depends on the relative abundance of species whose bark type favors epiphytes establishment.

МОДЕЛИРОВАНИЕ ЭЛЕКТРОДИНАМИЧЕСКИХ ПРОЦЕССОВ СВЧ-УСТАНОВОК С КВАЗИРЕЗОНАТОРАМИ ДЛЯ ТЕРМООБРАБОТКИ ПОСЛЕУБОЙНЫХ МЯСНЫХ КОНФИСКАТОВ

The aim of the work is to identify an effective design of radio sealed resonators with high intrinsic Q-factor and providing effective electric field strength by comparing the parameters of an electrodynamic system. Scientific tasks have been solved: to analyze the peculiarities of installations with ultrahigh-frequency power supply to quasi-resonators for heat treatment of meat raw materials in continuous mode; to develop digital models of quasi-resonators and to conduct computer modeling of electrodynamic processes of five modes in a coaxial resonator with a spiral inner cylinder; to develop a microwave installation with two resonators for heat treatment of raw materials. Computer modeling of quasi-resonators and modeling of electrodynamic processes in resonators was carried out in the CST Microwave Studio Suite program. The features of 13 installations with quasi-resonators have been developed and analyzed. The results of computer simulation of electrodynamic processes in a coaxial resonator with a spiral inner cylinder for five modes show that the main power is concentrated in an annular volume, and an increased concentration of the electric field is observed at the edges of the outer cylinder. To ensure a uniform distribution of waves, the average perimeter of the annular volume and the height of the cylinders are a multiple of half the wavelength. The volume of the coaxial resonator (0.205 m3 ) allows accumulating large energy in it (E is energy, I do not see the value in Fig. kJ/m3 ), and the losses due to conduction currents are small (the surface area of the resonator is 2.07 m2 ). The longitudinal components of the electric field strength (4–7 kV/cm) vary in different ways, in the inner cylinder and in the annular volume of the resonator, with a height of 0.765 m. The value of its own Q-factor has an order of up to 105. In coaxially arranged resonators, two features are implemented: if 101 there is a gap of no more than a quarter of the wavelength between the base and the shell of the cylindrical resonator, a standing wave is excited; the field strength of the traveling wave in the condenser part of the toroidal resonator is high enough (up to 15 kV/cm) and ensures uniform heating of the raw materials.

Microstructure and mechanical properties of phase change cloud concrete stone cementitious composites

In this study, a novel kind of phase-change cementitious composites with cloud concrete stone (CCS) as aggregate were prepared and studied. The CCS was synthesized with fly ash, slag, and other construction waste through water heat and autoclaving. The phase-change paraffin was absorbed into the CCS using the vacuum impregnation technique, and then the epoxy resin combined with cement powder was applied to the aggregate surface to prevent the leakage of phase-change materials (PCMs). The composite aggregate with phase change function was, thus, fabricated. A series of experiments were carried out to study and evaluate the molecular structure, physical phase, and phase transition temperature of encapsulated composite aggregate with the means of Fourier infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The PCM-cement composites were prepared by replacing coarse aggregates with the composite aggregate in proportions of 25%, 50%, 75%, and 100% in volume. To explore the strength degradation in view of the microscopic perspective, scanning electron microscopy (SEM), XRD, and Image-Pro-Plus (IPP) were used. The experimental results revealed that the effect of the micropores of CCS on the melting temperature of the phase-change aggregates (24.84 °C) is higher than that of the paraffin (22.91 °C). The mechanical experiments results demonstrated that the compressive strength and splitting strength losses in the PCM-cement composite with replacement ratios of 75% were 24% and 39%, respectively. The XRD results revealed that with the incorporation of PCM, the calcium silicate hydrate (C-S-H) in the hydration products decreased and the Ca/Si value in C-S-H decreased from 9.05 to 2.13, which is one of the reasons for the strength decline of the PCM-cement composites. The cracks in the interfacial transition zone between the aggregate and matrix became large with increasing admixture, and the pore characteristics gradually became more apparent. The strength of the PCM-cement composite decreased with the increase in the average porosity, pore size, and perimeter of the matrix material.

Nonlinear model predictive control of large-scale urban road networks via average speed control

Controlling traffic in large-scale urban road networks is a challenging problem. Aggregated dynamical models, based on the macroscopic fundamental diagram (MFD) of urban traffic, enable model-based control design. As an alternative to perimeter control actuation commonly used in MFD-based control, in this paper, we propose actuation over regional space-mean speeds, which we name average speed control. The method involves manipulation of regional speeds via instrumentation similar to variable speed limits in freeways, or using vehicle-to-infrastructure communication. We develop nonlinear model predictive control schemes considering actuation over average speed and perimeter control. Their performances are compared using simulations on congested scenarios, the results of which suggest potential of the method as an alternative or complementary actuation to perimeter control.

Investigation of the relationship between gel strength and microstructure of surimi gel induced by dense phase carbon dioxide based on quantitative analysis

The microstructure of a surimi product determines its quality. Dense phase carbon dioxide (DPCD) can induce surimi gel formation, and the gel strength of the product are significantly better than that of heat-induced gels. The study analysed the changes of the surimi from golden pompano gel strength during the process of DPCD-induced gelation, and the changes of microstructure based on quantitative analysis of scanning electron microscope (SEM) image using ImageJ 1.42 software. The correlations between gel strength and microstructure was investigated. The results showed that the DPCD treatment significantly increased the cross-linking degree (CLD) and gel strength of surimi, compared with the raw surimi. The CLD and gel strength of surimi increased with the increase of DPCD treatment pressure, temperature and time. Quantitative microscopic analysis revealed that the number of pores (n) in the surimi gels increased and then decreased. The apparent porosity (ƞa), average pore area (Aa), average pore perimeter (Pa), fractal dimension (Df) and pore equivalent diameter (d) increased with the increase of DPCD treatment pressure, temperature and time. Correlation analysis showed that the CLD, ƞa, Aa, Pa, Df, d and median pore perimeter (Pc-50) were strongly positively correlated with the gel strength. In contrast, lacunarity (L) is strongly negatively correlated with the gel strength. The linear correlation coefficients between the CLD, ƞa and Df and the gel strength are 0.97, 0.95 and 0.96, respectively. These results provide a technical basis for DPCD to process high-quality surimi products. These findings also offer a novel approach for the testing and evaluating of the quality of surimi products.

Предиктори цитолізу гепатоцитів інсулінорезистентних щурів за умов пре- та постнатального йододефіциту

Carbohydrate metabolism markers, thyroid profile indexes, transaminase activity and structural features of liver were studied, taking into account sexual dimorphism, in rats which were keeping on a high-fructose diet under conditions of adequate iodine supply and pre- and postnatal iodine deficiency. It was found that under fructose loading of animals with iodine deficiency the risk of insulin resistance (IR) development increases (HOMA-IR index in insulin-resistant male rats under conditions of pre- and postnatal iodine deficiency increases respectively by 22 and 13% compared to the data in animals that received a high-carbohydrate diet and adequate iodine supply). It is important, that in males and females with IR, the secretion of free triiodothyronine decreased by 36 and 40%, thyroid-stimulating hormone – by 28 and 34%, respectively, compared to the data of intact animals. The development of IR was accompanied by the activation of aminotransferases in blood serum (more in males). In particular, in male rats with IR under conditions of pre- and postnatal iodine deficiency, the activity of aspartate aminotransferase increased by 2.7 and 2.4 times, alanine aminotransferase – by 3.9 and 2.7 times, respectively, which led to a decrease of the de-Ritis index (more significantly against the background of prenatal iodine deficiency – by 25%) in relation to the data in animals that were on a standard diet. The activity of aminotransferases in rats with IR under conditions of iodine deprivation was higher than in animals with isolated iodine deficiency – by 11-56% and IR – by 13-47 %. In animals with IR, the presence of binucleated hepatocytes with a diffuse decrease in the number of glycogen granules in them and accumulation of glycoproteins in the wall of liver vessels were found. The foci of fatty dystrophy and pronounced zonal character of dystrophic processes in hepatocytes were identified in females, diffuse dystrophy prevailed in males. In the cytoplasm of hepatocytes of animals with IR under conditions of prenatal iodine deficiency, the lightening and the granularity, single granules of glycogen were observed. Under these conditions, the average perimeter (by 74%) and area (by three times) of hepatocytes, the average area of nucleus (by 3.1 times), the average perimeter (by 50%) and area (by 66%) of the nucleolus were increased compared to the control values. The structural changes were consistent with an increase of the transaminase activity. Thus, fructose loading and the development of IR acts as a trigger for cytolysis of hepatocytes, which increases under conditions of iodine deficiency, especially prenatal.

Morphometric Features of Cells of Cervical Intraepithelial Neoplasia Using Computer Aided Image Analysis

Aim: Our goal is to evaluate and compare the different cell morphometric parameters in the various categories of cervical intraepithelial neoplasia (CIN).&#x0D; Study Design: We conducted a cross-sectional study of all cervical intraepithelial neoplasia identified in some areas of biopsies of cervical carcinomas.&#x0D; Place and Duration of Study: The study was in the department of histopathology of LAUTECH Teaching Hospital, Osogbo from January 2006 to December 2015.&#x0D; Materials and Methods: The histologic slides produced were scanned using CS2 APERIO digital slide scanner with standard settings. The scanned slides were then viewed using Qu Path-0.3.2 software. All areas of cervical intraepithelial neoplasia were selected. The perimeter, area, maximum caliper, circularity, eccentricity, and the various measures of hematoxylin optic densities (OD) of the nucleus of the cells were measured. The cytoplasmic morphometric measurements and the nuclear-cell ratio were then estimated.&#x0D; Results: Two cases of CIN 1, one case of CIN 2 and one case of CIN 3 were seen in the background of the eighty-seven cases of cervical carcinomas seen during the study period. A total of 5,935 cells were in the annotated regions with cervical intraepithelial neoplasia. The cells in CIN 1 area are 3,828, CIN 2 area has 1183 cells and CIN 3 areas has 924 cells. Cells of CIN 3 had higher average nuclei hematoxylin optic density (OD), nuclei hematoxylin OD standard deviation and maximum hematoxylin OD than cells of CIN 2 and CIN 1. Cells of CIN 1 have higher average cell area, cell perimeter, cell circularity and mean cytoplasm eosin OD compared to cells of CIN 2 and 3.&#x0D; Conclusion: Computer-aided image analysis using Qu Path software can be very instrumental in differentiating the various categories of cervical intraepithelial neoplasia especially in fragmented biopsies.

Analysis of Performance Yield Parameters for Selected Polycrystalline Solar Panel Brands in South Africa

Electricity access is an essential factor for any nation’s fast-growing economic and technological development. Therefore, to meet the fast-growing world population, the adoption of a mix of energy sources, including renewable energy, is one of the ways to address the paucity supply of energy worldwide. In this paper, the performance yields of five solar photovoltaic (PV) modules, named PV1, PV2, PV3, PV4, and PV5, from different manufacturers were analyzed and compared to their respective cost benefits for profitable customer’s choice. The study on the panels was conducted at the geographical locations of 25.7535° S latitude and 28.2079° E longitude, with an average perimeter of 525.6 m in Pretoria, South Africa. The panels were installed without shading under the same condition of solar irradiation. The power output of each module was collected three times a day for six months. The analysis showed that the power outputs or performances of the respective modules are majorly affected by their surface temperatures as indicated by the values of multiple regression correlation of 92.9%, 96.9%, 99.1%, 97.2%, and 77.5% between the respective modules’ power outputs and temperature. The study also showed a techno-economic evaluation method that helps to economically alleviate the cost of solar PVs and balance the choice of the PV panels according to their short-term performances.

Delineating the urban walking environment in modern China: a descriptive assessment of pedestrian permeability around subway stations in central Hangzhou

ABSTRACT This project examines and discusses the spatial features that influence pedestrian permeability in central Hangzhou, China. It acknowledges the multifactorial nature of walkability and highlights the critical and complex role of pedestrian permeability in assessing walking environment. A descriptive indicator bundle is built to examine the permeability of the walking patterns in six study areas around subway transfer stations in the city of Hangzhou. To achieve an inclusive understanding of the walking environment in the given areas, the investigation employed indicators of intersection density, space syntax, walk shed, modified pedestrian route directness and area-weighted average perimeter to measure the different layers and attributes of pedestrian permeability. The results indicate that the walking conditions identified in this study are generally poor and those in the old city centre have relatively higher permeability than those in new built-up areas, and none of the cases is decisively permeable for walking in all three dimensions of spatial features (i.e. constitution, configuration and composition). The comparison of the metrics also suggest that pedestrian permeability involves multiple attributes and should be assessed by a collaboration of complementary measures rather than an assembly of single ones.

Topography of pleural epithelial structure enabled by en face isolation and machine learning.

Pleural epithelial adaptations to mechanical stress are relevant to both normal lung function and parenchymal lung diseases. Assessing regional differences in mechanical stress, however, has been complicated by the nonlinear stress-strain properties of the lung and the large displacements with ventilation. Moreover, there is no reliable method of isolating pleural epithelium for structural studies. To define the topographic variation in pleural structure, we developed a method of en face harvest of murine pleural epithelium. Silver-stain was used to highlight cell borders and facilitate imaging with light microscopy. Machine learning and watershed segmentation were used to define the cell area and cell perimeter of the isolated pleural epithelial cells. In the deflated lung at residual volume, the pleural epithelial cells were significantly larger in the apex (624 ± 247 μm2 ) than in basilar regions of the lung (471 ± 119 μm2 ) (p < 0.001). The distortion of apical epithelial cells was consistent with a vertical gradient of pleural pressures. To assess epithelial changes with inflation, the pleura was studied at total lung capacity. The average epithelial cell area increased 57% and the average perimeter increased 27% between residual volume and total lung capacity. The increase in lung volume was less than half the percent change predicted by uniform or isotropic expansion of the lung. We conclude that the structured analysis of pleural epithelial cells complements studies of pulmonary microstructure and provides useful insights into the regional distribution of mechanical stresses in the lung.

Anythink for CT-based aorta root measurements before transcatheter aortic valve replacement: measurement consistency with 3mensio and impact on short-term prognosis

To evaluate the consistency and reproducibility of aortic root measurements by Anythink, a semi-automated preoperative CT analysis software, with those of 3mensio. Sixty-seven patients undergoing transcatheter aortic valve replacement (TAVR) in the First Medical Center of Chinese PLA General Hospital from December, 2016 to February, 2022 were retrospectively enrolled in this study. A cardiology resident who completed his professional training used both the software Anythink and 3mensio (as the gold standard) to reconstruct the aortic root model and analyze the parameters of the aortic annulus and the surrounding structures. The correlation and consistency of the measurement results of two software were analyzed. Two independent residents also used Anythink software to repeat the measurements for the same patient for assessment of the reproducibility of Anythink measurements. The valve models were selected based on the measurements by Anythink and 3mensio, and similarities and differences of the two software in clinical valve selection were assessed. The measurements of the distances from the anulus plane to the left and right coronary ostium, average diameter of the anulus, anulus area, anulus perimeter, and the angle between the annulus and horizontal plane did not differ significantly between the two software (P > 0.05), and their measurements showed positive correlations (r= 0.884-0.981, P < 0.01). The intra-group and inter-group correlation coefficients of the anulus parameters measured by Anythink ranged from 0.894 to 0.992 and from 0.651 to 0.954, respectively. The Kappa-test values of valve models selected by Anythink and 3mensio based on the average diameter, area diameter and perimeter diameter were 0.886, 0.796 and 0.775, respectively. The intra-group Kappa values for the valve models selected based on Anythink measurements were 0.819, 0.841, and 0.795, and the inter-group Kappa values were 0.812, 0.812, and 0.768, respectively. Compared with the measurements by 3mensio, the recommended area diameter measured by Anythink was slightly greater in patients with postoperative paravalvular leakage, but slightly smaller in patients with postoperative new-onset conduction block. Anythink has excellent measurement consistency and high reproducibility for aortic root measurements, and trained cardiologists can use Anythink to obtain accurate aortic root parameters before TAVR.

Machine learning guided understanding of microstructural entropy decay in bimodal grain-size distributed alloys with combination of high-strength and high-ductility

Insights into the yield strength of metallic alloys have recently been revealed in terms of microstructure entropy (ME) per grain S* [Acta Materialia 195 (2020) 531–540]. Here, we report the decay of ME, which is taken as a phenomenological parameter, in steel alloy systems characterized by a bimodal grain size distribution and a combination of high-strength and high-ductility as the dynamics of the grain growth approaches a self-similar regime. The self-similar bimodal grain distribution was realized by an innovative phase reversion strategy of the 60 groups steel alloys. An increase in tann and/or Tann resulted in an increase in S* and a decay in the total entropy, Sm, due to the more significant effect of the grain number decreases than that of the S* growth. The Sm, the average grain perimeter (p¯), and the average grain volume (v¯) exhibited close relationships with the mean grain surface area (a¯) during the grain growths and the ME degenerations. The decay of ME, caused by the system approaching a self-similar regime during the grain growth, is well explained following the first and second laws of thermodynamics, which has further been studied via machine learning. Three linear regression models were established with high prediction accuracy. Using these well trained machine learning models, with any continuous or random Ln (a¯, μm2) as the input, we can predict the Ln (Sm, μm−3), Ln (p¯, μm), and Ln (v¯, μm3), which are related to the microstructure and properties of different materials, within millisecond.

Accuracy of anthropometric indicators of obesity to identify high blood pressure in adolescents-systematic review.

BackgroundAnthropometric indicators of obesity have been associated with blood pressure in adolescents. However, the accuracy of anthropometric indicators of obesity for screening for high blood pressure (HBP) in adolescents is not known. Thus, the aim of the present study was to summarize the set of evidence regarding the predictive ability of anthropometric indicators of obesity to identify HBP in adolescents.MethodsSearches were performed in five databases: MEDLINE, Web of Knowledge, Scopus, Scientific Electronic online (SciELO) and SportDiscus. The inclusion criteria for studies were: adolescents aged 10–19 years or mean age included in this range, observational and intervention studies, studies that proposed cutoff points for anthropometric indicators of obesity, and studies in English, Portuguese and Spanish. The methodological quality of studies was assessed using the QUADAS-2 instrument.ResultsTen studies met the inclusion criteria and had their information summarized. Based on the information described in these studies, the anthropometric indicators body mass index (BMI), waist circumference (WC), waist-to-height-ratio (WHtR), triceps skinfold thickness, body adiposity index, C index, body mass, waist-to-arm span ratio, arm fat area, average arm perimeter, fat percentage and arm span were likely to be used in high blood pressure (HBP) screening among adolescents. However, only one study showed acceptable values (moderate to high precision) in relation to the accuracy measurements of described cutoffs.ConclusionCaution is suggested in the use of anthropometric indicators of obesity for HBP screening in adolescents, in which a greater number of studies with accurate diagnostic tools are necessary.