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Wireless positioning and tracking technology are key technologies in applying wireless sensor networks and have vital research significance and application value. In this paper, in terms of positioning multiple non-coincident dynamic targets, aiming at the problem of low precision and large computational complexity when locating multiple dynamic targets by the two-step least squares algorithm and the constrained total least squares algorithm, an improved constrained total least squares algorithm is proposed. This algorithm fully considers the constraints, introduces the Lagrangian multiplier technology and the quasi-Newton BFGS iterative formula, avoids the calculation of the Hessian matrix, reduces the amount of calculation, and improves the positioning accuracy. Simulation experiments show that when the measurement error and sensor position error are moderate, the ICTLS positioning algorithm has a smaller RMSE than the TSWLS and CTLS positioning algorithms, showing higher positioning accuracy and stronger robustness. Secondly, aiming at the problem that the target is close to the reference node or any coordinate axis causes the positioning error of the traditional positioning algorithm to increase sharply, an optimized two-step least squares algorithm is proposed. This algorithm corrects the defects of the TSWLS algorithm by selecting the reference station and rotating the coordinate system again, and improves the positioning performance of the algorithm while reducing the amount of calculation. [ABSTRACT FROM AUTHOR]

Abstract: The objective was to determine the effects of various methods of oocyte activation and sperm pretreatment on development of porcine embryos derived from in vitro-matured oocytes and intracytoplasmic sperm injection (ICSI). The second polar body was extruded in the majority (>78.4%) of in vitro-matured (IVM) oocytes 4h after electrical pulse activation. In embryos generated by ICSI and sham-ICSI, a combination of an electrical pulse, with various chemical activators 4h later, improved (P <0.05) blastocyst formation rate compared to activation only with a pulse. Treatment with 6-dimethylaminopurine (DMAP) after electrical activation significantly increased the oocyte activation rate. The effects of exposure of sperm to repeated freeze-thaw cycles (without cryoprotectant) on oocyte activation and the effects of sperm pre-incubated with dithiothreitol (DTT) or Triton X-100 on early embryo development were also examined. Blastocyst formation rates after ICSI did not differ between motile sperm and those rendered immotile by one-time freezing and thawing without cryoprotectant. However, sperm rendered immotile by three cycles of freezing/thawing without cryoprotectant had a significantly lower blastocyst formation rate. Although oocytes injected with sperm pre-incubated with Triton X-100 had a higher normal fertilization rate than those pre-incubated with DTT or one-time frozen/thawed sperm, rates of blastocyst formation and cell numbers were similar among the three groups. In conclusion, various methods of oocyte activation and sperm preparation significantly affected the developmental capacity of early porcine embryos derived from IVM and ICSI. [Copyright &y& Elsevier]

Circadian rhythm disruptions and heat stress can cause gut microbiota dysbiosis and intestinal barrier damage, increasing the risk of inflammatory bowel disease. However, whether eating according to the circadian rhythm during the day when the ambient temperature is higher or eating against the circadian rhythm at night when the ambient temperature is relatively suitable, is better for the gut health of diurnal animals in summer has not been clarified. In this study, growing pigs were randomly assigned to a daytime‐restricted feeding or nighttime‐restricted feeding (NRF) group and raised for 18 days in summer with mild heat stress. Our results showed that NRF alleviated heat stress in pigs, as reflected by increased feed intake and decreased drinking. Microbiome analysis revealed that NRF increased the diversity of gut microbiota and abundance of short‐chain fatty acids (SCFAs)‐producing bacteria and decreased the abundance of gram‐negative and potentially pathogenic bacteria, thereby increasing SCFAs and reducing lipopolysaccharide production in the colon. These changes enhanced colonic barrier function and reduced colitis and systemic inflammation by upregulating tight junction proteins and mucin. Our findings indicate that although nighttime eating does not align with the biological habits of pigs, consuming food at a relatively suitable ambient temperature is more beneficial for gut health and homeostasis during hot seasons. Our research provides a reference for guiding the healthy feeding of farm animals in summer and a basis for developing a lifestyle that promotes gut health for individuals in tropical regions. [ABSTRACT FROM AUTHOR]

"Demonstration farms" can disseminate knowledge on farming practices and help to promote animal welfare. When on-farm visits are impractical, remote demonstrations are a feasible alternative. This study used videos of higher welfare beef, fish and free-range egg farms in China. It aimed to determine whether the videos affected attitudes and intentions toward animal welfare and whether such videos are useful training tools. Participants indicated a high acceptability of demonstration farm videos for learning about their industry and the needs of animals. Videos shifted participant attitudes toward animal welfare, but only when actively engaged in rating the farm on specific characteristics. Attitude changes suggested participants gained a greater understanding of animal welfare, a greater intention to improve on-farm welfare, and more confidence in peer support for welfare innovations after viewing the video. The findings indicate videos of demonstration farms are useful for remote training but passive viewing may be insufficient to create change, and outcomes should be monitored for success. [ABSTRACT FROM AUTHOR]

A decline in semen quality caused by global warming and torrid working conditions is a major cause of human male infertility, and heat stress-induced decreases in male reproductive ability results in economic losses in livestock husbandry. Increasing evidence suggests that melatonin exerts protective effects on stress-induced DNA damage and apoptosis in germ cells. However, few studies have assessed the effects of melatonin on testicular recovery during post-heat stress and the underlying mechanisms. In vivo studies using 8-week-old male CD-1 mice revealed that melatonin pretreatment (50 mg/kg for 5 days) did not alleviate heat stress-induced germ cell loss and disrupted testicular histomorphology, however, long-term melatonin administration after heat stress accelerated germ cell apoptosis, spermatogenic cell regeneration, and testicular weight recovery. In vitro studies demonstrated that melatonin enhanced RAC1 activity, resulting in increased phagocytosis of apoptotic germ cells by Sertoli cells. In addition, melatonin restored gap junctions and tight junctions after heat stress, thereby promoting hollow seminiferous tubule filling. Long-term melatonin administration accelerated testicular recovery after heat stress by enhancing the phagocytotic activity of Sertoli cells and the regeneration of spermatogenic cells. This finding suggests that melatonin is a potential therapeutic for heat stress-induced male infertility. • Long-term melatonin administration after heat stress accelerated germ cell apoptosis. • Melatonin enhanced RAC1-mediated phagocytosis ability of Sertoli cells to eliminate apoptotic germ cells. • Melatonin accelerates recovery from testicular heat damage by promoting cell junction-dependent germ cell regeneration. [ABSTRACT FROM AUTHOR]

An unfavorable lifestyle disrupts the circadian rhythm, leading to metabolic dysfunction in adult humans and animals. Increasing evidence suggests that night‐restricted feeding (NRF) can effectively prevent ectopic fat deposition caused by circadian rhythm disruption, and reduce the risk of metabolic diseases. However, previous studies have mainly focused on the prevention of obesity in adults by regulating dietary patterns, whereas limited attention has been paid to the effect of NRF on metabolism during growth and development. Here, we used weaning rabbits as models and found that NRF increased body weight gain without increasing feed intake, and promoted insulin‐mediated protein synthesis through the mTOR/S6K pathway and muscle formation by upregulating MYOG. NRF improved the circadian clock, promoted PDH‐regulated glycolysis and CPT1B‐regulated fatty‐acid β‐oxidation, and reduced fat content in the serum and muscles. In addition, NRF‐induced body temperature oscillation might be partly responsible for the improvement in the circadian clock and insulin sensitivity. Time‐restricted feeding could be used as a nondrug intervention to prevent obesity and accelerate growth in adolescents. [ABSTRACT FROM AUTHOR]

Assisted reproductive technology (ART) is being increasingly applied to overcome infertility. However, the in vitro production process, the main procedure of ART, can lead to aberrant embryonic development and health-related problems in offspring. Understanding the mechanisms underlying the ART-induced side effects is important to improve the ART process. In this study, we carried out comparative transcriptome profiling between in vivo- (IVO) and in vitro- produced (IVP) mouse blastocysts. Our results suggested that aberrant actin organization might be a major factor contributing to the impaired development of IVP embryos. To test this, we examined the effect of actin disorganization on the development of IVP preimplantation embryos. Specific disruption of actin organization by cytochalasin B (CB) indicated that well-organized actin is essential for in vitro embryonic development. Supplementing the culture medium with 10–9 M melatonin, a cytoskeletal modulator in adult somatic cells, significantly reversed the disrupted expression patterns of genes related to actin organization, including Arhgef2, Bcl2, Coro2b, Flnc, and Palld. Immunofluorescence analysis showed that melatonin treatment of IVP embryos significantly improved the distribution and organization of actin filaments (F-actin) from the 8-cell stage onwards. More importantly, we found that melatonin alleviated the CB-mediated aberrant F-actin distribution and organization and rescued CB-induced impaired embryonic development. This is the first study to indicate that actin disorganization is implicated in impaired development of IVP embryos during the preimplantation stage. We also demonstrated that improving actin organization is a promising strategy to optimize existing IVP systems. [ABSTRACT FROM AUTHOR]

This study focused on the effect of melatonin on reprogramming with specific regard to the generation of induced pluripotent stem cells (i PSCs). Here, a secondary inducible system, which is more accurate and suitable for studying the involvement of chemicals in reprogramming efficiency, was used to evaluate the effect of melatonin on mouse i PSC generation. Secondary fibroblasts collected from all-i PSC mice through tetraploid complementation were cultured in induction medium supplemented with melatonin at different concentrations (0, 10−6, 10−7, 10−8, 10−9, or 10−10 m) or with vitamin C (50 μg/mL) as a positive control. Compared with untreated group (0.22 ± 0.04% efficiency), 10−8 (0.81 ± 0.04%), and 10−9 m (0.83 ± 0.08%) melatonin supplementation significantly improved reprogramming efficiency ( P < 0.05). Moreover, we verified that the i PSCs induced by melatonin treatment ( Mi PSCs) had the same characteristics as typical embryonic stem cells ( ESCs), including expression of the pluripotency markers Oct4, Sox2, and Nanog, the ability to form teratomas and all three germ layers of the embryo, as well as produce chimeric mice with contribution to the germ line. Interestingly, only the melatonin receptor MT2 was detected in secondary fibroblasts, while Mi PSCs and ESCs expressed MT1 and MT2 receptors. Furthermore, during the early stage of reprogramming, expression of the apoptosis-related genes p53 and p21 was lower in the group treated with 10−9 m melatonin compared with the untreated controls. In conclusion, melatonin supplementation enhances the efficiency of murine i PSC generation. These beneficial effects may be associated with inhibition of the p53-mediated apoptotic pathway. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effect of melatonin during the culture of donor cells and cloned embryos on the in vitro developmental competence and quality of cloned porcine embryos. At concentrations of 10-6 m or 10-8 m, melatonin significantly enhanced the proliferation of porcine fetal fibroblasts (PFFs), and the blastocyst rate was significantly increased in the 10-10 m melatonin-treated donor cell group. Cloned embryo development was also improved in embryo culture medium that was supplemented with 10-9 m or 10-12 m melatonin. When both donor cells and cloned embryos were treated with melatonin, the cleavage rate and total cell number of blastocysts were not significantly affected; however, the blastocyst rate was increased significantly (20.0% versus 11.7%). TUNEL assays showed that combined melatonin treatment reduced the rate of apoptotic nuclei (3.6% versus 6.1%). Gene expression analysis of the apoptosis-related genes BAX, BCL2L1, and p53 showed that the expression of BCL2L1 was significantly elevated 2.7-fold relative to the control group, while the expression of BAX and p53 was significantly decreased by 3.7-fold and 23.2-fold, respectively. In addition, we detected the expression of two melatonin receptors (MT1 and MT2) in PFFs but not in porcine cloned embryos. We conclude that exogenous melatonin enhances the development of porcine cloned embryos and improves embryo quality by inhibiting p53-mediated apoptotic pathway. The proliferation of PFFs may be mediated by receptor binding, but the beneficial effects of melatonin on embryonic development may be receptor-independent, possibly through melatonin's ability to directly scavenge free radicals. [ABSTRACT FROM AUTHOR]

Abstract: In general, a diet enriched in polyunsaturated fatty acids (PUFAs) inhibits the development of obesity and decreases adipose tissue. The specific impacts of n-3 and n-6 PUFAs on adipogenesis, however, have not been definitively determined. Traditional in vivo and in vitro supplementation studies have yielded inconsistent or even contradictory results, which likely reflect insufficiently controlled experimental systems. Caenorhabditis elegans fat-1 gene encodes an n-3 fatty acid desaturase, and its heterologous expression represents an effective method both for altering the n-6/n-3 PUFA ratio and for evaluating the biological effects of n-3 and n-6 PUFAs. We sought to determine whether a reduced n-6/n-3 ratio could influence adipogenesis in 3T3-L1 cells. Lentivirus-mediated introduction of the fat-1 gene into 3T3-L1 preadipocytes significantly reduced the n-6/n-3 ratio and inhibited preadipocyte proliferation and differentiation. In mature adipocytes, fat-1 expression reduced lipid deposition, as measured by Oil Red O staining, and induced apoptosis. Our results indicate that a reduced n-6/n-3 ratio inhibits adipogenesis through several mechanisms and that n-3 PUFAs more effectively inhibit adipogenesis (but not lipogenesis) than do n-6 PUFAs. [Copyright &y& Elsevier]