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PANI/COF/BiOBr catalysts were synthesized by hydrothermal method basing on Schiff base reaction. The composites were characterized by XRD, SEM, etc., and at the same time, the photocatalytic property and degradation mechanism of PANI/COF/BiOBr catalysts were studied by degrading organic simulated dyes. The experimental results showed that the main structure of PANI/COF/BiOBr composite was flower ball structure with BiOBr main crystal type of tetragonal phase, and the degradation rates of PANI/COF/BiOBr were 1.44, 1.55 and 1.47 times of pure BiOBr for Rhodamine B, methylene blue and tetracycline hydrochloride, respectively. The free radical quenching experiment showed that h+ and e- were the most active species in the photocatalytic process. [ABSTRACT FROM AUTHOR]

The composite catalysts were prepared by two-step photothermal synthesis, and the morphology, structure and catalytic performance of the Ag/graphene/TiO2 composite were characterized by SEM, FT-IR, XRD, etc. The results showed that the composites were prepared successfully by Ag depositing on TiO2 compounded with graphene, and solid UV diffuse reflection test showed that Ag/Graphene/TiO2 composites had the greatest enhancement in the absorption of visible light. The results showed that among four kinds materials, the methyl orange's degradation rate of Ag/Graphene/TiO2 in simulated visible light reached best, whose degradion was 4.25 times that of pure TiO2. The number of photocatalytic experiments showed that Ag/Graphene/TiO2 photogenerated electrons and the corresponding generated O2· dominated the catalysis. [ABSTRACT FROM AUTHOR]

The split ratio, i.e., the ratio of rotor outer diameter to stator outer diameter, is one of the most vital design parameters for permanent-magnet (PM) machines due to its significant impact on the machine torque or power density. However, it has been optimized analytically in the existing papers with due account only for the stator copper loss, which is reasonable for low-to-medium speed PM machines. For high-speed PM machines (HSPMMs), the negligence of stator iron loss and the mechanical stress on the rotor will lead to a deviation of optimal split ratio and actual torque capability. In this paper, the optimal split ratio of HSPMM is investigated analytically with the consideration of stator iron loss as well as the mechanical stress on the rotor. The influence of air-gap length and rotor pole pairs on the optimal split ratio is elaborated. Both the analytical and finite-element analysis reveal that the optimal split ratio for HSPMM will be significantly reduced, when stator iron loss and mechanical constraints are taken into account. [ABSTRACT FROM AUTHOR]

In this paper, four rotor shaping methods, i.e., eccentric circular, inverse cosine, inverse cosine with third harmonic, and multi-step shaping methods, are developed and compared for torque ripple mitigation in variable flux reluctance machines (VFRMs). By using a 6-stator-pole/7-rotor-pole (6/7) VFRM as an example, the design criterions and capabilities of these four methods are illustrated. It is found that all the rotor shaping methods are capable of torque ripple mitigation and applicable to all the VFRMs except those with 6k/(6i ± 2) k (k, i = 1, 2, 3…) stator/rotor pole combinations. Moreover, the inverse cosine with third harmonic and multi-step shaping methods are found to have the best performance. They are able to reduce the torque ripple by 90% at a cost of only 3% torque density reduction. A 6/7 VFRM with both conventional and shaped rotors is prototyped and tested for verification. [ABSTRACT FROM AUTHOR]

The intestinal microbiome has been shown to influence animal nutrient metabolism and immune homeostasis. The present study aimed to examine the effect of heat stress on the intestinal microbiome of broilers using pyrosequencing technologies. Ninety-six Arbor Acres broiler chicks were allocated to thermoneutral control (TC; 21 ± 1°C) and high ambient temperature (HT; 31 ± 1°C) groups (6 cages of 8 birds per group), respectively, and raised in 2 controlled climate chambers from 28 to 42 d old. Genomic DNA was extracted from ileal contents isolated from 6 male broiler chicks of each group at 42 d old, and then amplified based on the V3-4 hyper-variable region of 16S rRNA. High temperature had no significant effects, but tended to influence the relative abundance of major phyla and orders in the broilers' ileal microbiota. Analysis of linear effect size feature selection identified 9 discriminative features (genus level, linear discriminant analysis score > 3). Clostridium XIVb, Streptophyta, Faecalibacterium, Rothia, Alistipes, Azospirillum, and Oscillibacter were enriched, while Coprococcus and Streptococcus were reduced in heat-stressed broilers. High temperature significantly influenced the alpha diversity, with higher observed species (P = 0.004), whole-tree phylogenetic diversity (P = 0.002), and Chao 1 (P = 0.002), but the Pielou, Shannon, and Simpson indices were unaltered (P > 0.05), indicating that high temperature increased the ileal microbiota species richness. Based on unweighted UniFrac distance metric matrices, principal component analysis showed that the HT group formed a distinct cluster clearly set apart from the TC group. Analysis of similarity also indicated that samples within groups were more similar to each other than to any samples from other groups (R = 0.626; P = 0.004). In conclusion, high temperature influenced the bacterial composition and community structure of the ileal microbiota of broilers, specifically by increasing the species richness. [ABSTRACT FROM AUTHOR]

In this paper, the torque production mechanism of variable flux reluctance machines (VFRMs) is investigated. Initially, based on an analytical instantaneous torque model developed from the Lorentz force law and airgap field harmonic analysis, the magnetic gearing effect is revealed in the torque production of VFRMs. Then, by using a 6-stator-pole/4-rotor pole (6s/4r) VFRM as an example, all its torque components, including synchronous torque, reluctance torque, and cogging torque, are analyzed separately under linear condition. Their average torque and torque ripple characteristics are comprehensively illustrated. Finally, the influence of saturation effect is also accounted for with the help of finite element and frozen permeability methods. The analysis results are verified experimentally. [ABSTRACT FROM AUTHOR]

This study was undertaken to investigate the effects of ambient temperature, crude protein levels and their interaction on performance and serum biochemical parameters of broiler chickens. A total of 216 Arbor Acre broiler chickens (108 males and 108 females) were used in a 2 × 3 factorial arrangement and randomly reared at two temperatures (normal temperature: 23 °C; daily cyclic high temperature: 28-32 °C) and fed on three diets with different crude protein levels (153.3, 183.3 or 213.3 g/kg, with constant essential amino acids) from 28 to 42 days of age. Daily cyclic high ambient temperature decreased final body weight, average daily weight gain, average daily feed intake and serum total protein contents (p < 0.001, p < 0.001, p < 0.001, p = 0.008 respectively), but increased feed/gain, mortality, respiratory rate, rectal temperature, serum uric acid contents and serum creatine kinase activity (p = 0.008, p = 0.003, p < 0.0001, p < 0.0001, p < 0.0001, p = 0.003 respectively), irrespective of crude protein levels. At the ambient temperature, reducing crude protein levels resulted in an increase in feed/gain (p < 0.001), but a decrease in serum total protein and uric acid contents. Only serum creatine kinase activity in broiler chickens was interacted by daily cyclic high ambient temperature and dietary crude protein levels (p = 0.003). These results indicated that daily cyclic high ambient temperature had a great effect on performance and serum biochemical parameters in broiler chickens, whereas dietary crude protein levels affected them partially. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of immunological challenge on the skeletal muscle fiber type conversion of piglets. Sixteen Large White weaned barrows (28 ± 3 d, 8.22 ± 0.89 kg BW) were allotted by weight and litter to 2 groups: the control group and the lipopolysaccharide (LPS) group. Saline (control) or LPS was injected intravenously via a jugular catheter on d 1, 3, 5, 7, 9, 11, 13, and 15 at an initial dosage of 80 μg/kg BW, which was increased by 30% at each subsequent injection. Blood samples were collected via the jugular catheter 3 h after the LPS challenge on d -1, 1, 5, 9, and 13. Muscle tissue samples were collected from the LM after exsanguination on d 15. The LPS challenge increased the plasma IL-6, tumor necrosis factor-α (TNF-α), cortisol, IL-1β, and haptoglobin concentrations on d 1 and 5 (P < 0.01) and increased the plasma IL-6 (P < 0.05), TNF-α (P < 0.05), and haptoglobin (P < 0.01) levels on d 9. Compared with that of the control group, the ADG of the LPS group decreased by 40.00% (P < 0.01), 29.52% (P < 0.05), and 19.30% (P < 0.05), and the ADFI decreased by 25.09% (P < 0.01), 23.15% (P < 0.05), and 19.47% (P < 0.05) during d 1 to 4, d 5 to 8, and d 9 to 15, respectively. In the LM of LPS-challenged piglets, myosin heavy chain 1 (MyHC1) mRNA and protein expression tended to be reduced (P = 0.08, 0.09), whereas MyHC2x mRNA, MyHC2b mRNA, and MyHC2 protein expression increased (P < 0.05). The LPS challenge reduced succinic dehydrogenase (SDH) activity (P < 0.05) and increased lactate dehydrogenase (LDH) activity (P < 0.05) in the LM of piglets. Compared with those in the control group, transcriptional peroxisome proliferatoractivated receptor coactivator-α (PGC-α) mRNA (P < 0.05), calcineurin (CaN) mRNA, and protein expression were reduced (P < 0.05), and PGC-α protein expression tended to be reduced (P = 0.08) in the LM of LPS-challenged piglets. These results show that immunological challenge induced by LPS resulted in a shift from type I to type II fibers in the LM of piglets, which may be mediated by the downregulation of the CaN/PGC-a signaling pathway. [ABSTRACT FROM AUTHOR]

We report a study of the anharmonic lattice dynamics in low lattice thermal conductivity (κl) material AgCrSe2 by many-body perturbation theory. We demonstrate surprisingly giant four-phonon scattering exclusive for the heat-carrying transverse acoustic phonons due to large quartic anharmonicity and nondispersive phonon band structure, which lead to four-phonon Fermi resonance and breaks the classical t-1∼ωmTn relation for phonon-phonon interactions. This strong resonant scattering extends over the Brillouin zone and substantially suppresses the thermal transport, even down to a low temperature of 100 K. The present results provide fundamental insights into the four-phonon resonant dynamics in the low-κl system with flat phonon dispersions, i.e., cuprous halides and skutterudites. [ABSTRACT FROM AUTHOR]

In this article, we propose a novel switching-table-based direct torque control (ST-DTC) method to eliminate the current harmonics in dual-three-phase permanent-magnet synchronous machines due to the back electromotive force (back EMF) harmonics and voltage vector selection. By employing a novel space voltage vector selection strategy and the optimal action time for different groups of vectors, a novel ST-DTC method is developed. Furthermore, in order to implement standard pulsewidth modulation (PWM) switching sequence, a centralization PWM method for 36 voltage vectors is introduced. The proposed method can effectively reduce the phase current harmonics caused by both back EMF distortion and voltage vector selection, and still reserve the advantages of the conventional ST-DTC, such as fast torque response and simple structure. Its effectiveness is verified by simulations and experiments. [ABSTRACT FROM AUTHOR]

In order to measure the real-time variations in body temperature with increasing ambient temperature (AT) at different relative humidity (RH) levels, 60 Jinghong laying hens (35-wk-old) were raised in 3 controlled climate chambers (10 cages with 2 birds per chamber). The RH was fixed at one of 3 levels comprising 35, 50, or 85%, and the AT was increased gradually by 1 degree per 0.5 h from 18 to 35°C in the 3 chambers. The core temperature (CT) and surface temperature (ST) of the hens, as well as the AT in the 3 chambers were recorded at 3 min intervals using mini temperature data loggers. The data were analyzed with a broken-line model to determine the inflection point temperature (IPT, the certain AT above which the body temperature of the hens started to change). The experiment was repeated 3 times on 3 d. The IPTs of the laying hens were 23.89 and 25.46°C based on ST and CT at 50% RH, respectively, which indicated that the upper critical temperature of the thermoneutral zone of hens may be a specific temperature between 23.89°C and 25.46°C. The IPTs of the laying hens were 24.11 and 25.20°C based on ST and CT at RH 35%, respectively, and 21.93 and 24.45°C at RH 85%. The RH significantly affected the IPT of ST (P < 0.001). The IPTs were higher at 35 and 50% RH than that at 85% RH (P < 0.05). The coefficients of variation for the IPTs between individual hens were 2.96 to 4.51, and coefficients of variation for the IPTs for the same bird measured on 3 d were 0.69 to 1.59, thereby indicating that this method for estimating the IPTs of hens is stable and repeatable, although more samples are needed. In conclusion, our results indicate that analyzing the real-time variation in body temperature with increasing AT is a reliable method for estimating the IPT to provide an important reference for regulating the temperature in poultry houses. [ABSTRACT FROM AUTHOR]

In this paper, a novel nonconventional angle displacement (i.e., 15°) between two sets of three-phase windings is proposed for dual three-phase permanent-magnet (PM) machines. First, all feasible angle displacements between the two three-phase winding sets for various slot/pole number combinations of dual three-phase machines are discussed in general. Then, an in-depth investigation is carried out on a 24-slot/10-pole dual three-phase PM machine as an example covering various electromagnetic performances. The investigation shows that under healthy and three-phase open-circuit conditions, the proposed 15° configuration has a comparable electromagnetic performance to the 30° configuration, and a better performance than the 0° counterpart. Furthermore, under three-phase short-circuit (SC) condition, the proposed 15° configuration has the lowest SC current, smallest braking torque, and the best PM demagnetization withstand capability. Finally, three prototype 24-slot/10-pole surface-mounted PM machines are built and tested to verify the theoretical analyses. [ABSTRACT FROM PUBLISHER]

The aim of this study was to assess the correlation of sperm morphology with the intrauterine insemination ( IUI) outcome in patients with normal sperm concentration and motility. About 412 couples who underwent 908 IUI cycles were involved in the present study. A total of 110 clinical pregnancies were achieved with a pregnancy rate of 12.11% per cycle. The pregnancy rates per cycle were 7.60%, 12.67%, 13.62% and 13.13% in patients with <5%, 5-9%, 10-14% and >14% normal forms, respectively. The lowest pregnancy rate (7.60%) was obtained in the group with normal forms below 5%. However, this rate was not significantly different from other subgroups. Moreover, no pregnancies occurred in women >35 years old with normal sperm forms below 5%, in comparison with that in other subgroups of the same age. For women younger than 35 years old, no significant difference in pregnancy rate was observed in terms of different level of morphologically normal sperm. Our results show that for patients with normal sperm concentration and motility, IUI is recommended for first-line treatment when the woman is younger than 35 years, or morphologically normal sperm is ≥5%. IVF/ ICSI should be performed when the normal forms are <5% and female age is >35 years. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the effects of acute heat stress on the concentration of free Ca2+ ([Ca2+]i) and markers of cellular immunity in splenic lymphocytes from broiler chickens. Eighty 6-wk-old male broilers were randomly allocated to 2 treatments and exposed to 25 and 35°C (RH, 50 ± 5%) for 3 h. We observed that 3 h of heat exposure (35 ± 1°C, 50 ± 5% RH) increased the body temperature and respiratory rate of broiler chickens significantly, but plasma levels of corticosterone were not changed. Examination of [Ca2+]i and the proliferation of splenic lymphocytes isolated from heat-stressed broiler chickens, using fura-2-acetoxymethyl ester and Cell Counting Kit-8, respectively, showed that acute heat stress caused a significant increase in [Ca2+]i and enhanced concaAavalin A-stimulated but not lipopolysaccharidestimulated lymphocyte proliferation significantly. Flow cytometric analysis of the cell cycle and T-lymphocyte subsets (CD4+ and CD8+) indicated that heat stress promoted the transition of lymphocytes from gap phase 1 to synthesis phase and increased the ratio of CD4+ to CD18+ of T lymphocytes. In addition, acute heat stress enhanced the secretion of interleukin-2 by splenic lymphbcytes significantly. These results suggest that the effect of acute heat stress to increase the [Ca2+]i in lymphocytes may be an early event that enhances Con A-stimulated T-cell proliferation and interleukin-2 secretion and promotes the transition of T cells from gap phase 1 to synthesis phase. [ABSTRACT FROM AUTHOR]

This study investigated the effects of different acute high ambient temperatures on dysfunction of hepatic mitochondrial respiration, the antioxidative enzyme system, and oxidative injury in broiler chickens. One hundred twenty-eight 6-wk-old broiler chickens were assigned randomly to 4 groups and subsequently exposed to 25 (control), 32, 35, and 38°C (RH, 70 ± 5%) for 3 h, respectively. The rectal temperatures, activity of antioxidative enzymes (superoxide dismutase, catalase, and glutathione peroxidase), content of malondialdehyde and protein carbonyl, and the activity of mitochondrial respiratory enzymes were determined. The results showed that exposure to high ambient temperature induced a significant elevation of rectal temperature, antioxidative enzyme activity, and formation of malondialdehyde and protein carbonyl, as well as dysfunction of the mitochondrial respiratory chain in comparison with control (P < 0.05). Almost all of the indicators changed in a temperature-dependent manner with the gradual increase of ambient temperature from 32 to 38°C; differences in each parameter (except catalase) among the groups exposed to different high ambient temperatures were also statistically significant (P < 0.05). The results of the present study suggest that, in the broiler chicken model used here, acute exposure to high temperatures may depress the activity of the mitochondrial respiratory chain. This inactivation results subsequently in overproduction of reactive oxygen species, which ultimately results in oxidative injury. However, this hypothesis needs to be evaluated more rigorously in future studies. It has also been shown that, with the gradual increase in temperature, the oxidative injury induced by heat stress in broiler chickens becomes increasingly severe, and this stress response presents in a temperature-dependent manner in the temperature range of 32 to 38°C. [ABSTRACT FROM AUTHOR]

Summary. Cladograms of iridoviruses were inferred from bootstrap analysis of molecular data sets comprising all published protein and DNA sequences of the major capsid protein, ATPase and DNA polymerase genes of members of the Iridoviridae family Iridovirus. All data sets yielded cladograms supporting the separation of the Iridovirus, Ranavirus and Lymphocystivirus genera, and the cladogram based on data derived from major capsid proteins further divided both the Iridovirus and Ranavirus genera into two groups. Tests of alternative hypotheses of topological constraints were also performed to further investigate relationships between infectious spleen and kidney necrosis virus (ISKNV), an unclassified fish iridovirus for which the complete genome sequence data is available, and other iridoviruses. Cladograms inferred and results of Shimodaira–Hasegawa tests indicated that ISKNV is more closely related to the Ranavirus genus than it is to the other genera of the family. [ABSTRACT FROM AUTHOR]