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Laser weld point detection is crucial in modern industrial manufacturing, yet it faces challenges such as a limited number of samples, uneven distribution, and diverse, irregular shapes. To address these issues, this paper proposes an innovative model, YOLO-Weld, which achieves lightweight design while enhancing detection accuracy. Firstly, a targeted data augmentation strategy is employed to increase both the quantity and diversity of samples from minority classes. Following this, a Diverse Class Normalization Loss (DCNLoss)function is designed to emphasize the importance of tail data in the model’s training. Secondly, the Adaptive Hierarchical Intersection over Union Loss (AHIoU Loss)function is introduced, which assigns varying levels of attention to different Intersections over Union (IoU) samples, with a particular focus on moderate IoU samples, thereby accelerating the bounding box regression process. Finally, a lightweight multi-scale feature processing module, MSBCSPELAN, is proposed to enhance multi-scale feature handling while reducing the number of model parameters. Experimental results indicate that YOLO-Weld significantly improves the accuracy and efficiency of laser weld point detection, with mean Average Precision at 50 ( ) and mean Average Precision at 50:95 ( ) increasing by 15.6% and 15.8%, respectively. Additionally, the model’s parameter count is reduced by 0.4 M, GFLOPS decreases by 1.1, precision improves by 4.3%, recall rises by 22.2%, and the F1 score increases by 15.1%.

We empirically examine the impact of expanded product variety on demand concentration using large data sets from the movie rental industry as our test bed. We find that product variety is likely to increase demand concentration, which goes against the “long tail effect” theory predicting that demand will become less concentrated on “hit” products because of expanded product variety. We further provide evidence that this finding is not due to introducing many low-selling niche products, as the intuition might suggest. Instead, we discover that increasing product variety diversifies the demand away from each movie title, but less significantly for hits than for niche products. In particular, we find that increasing product variety by 1,000 titles may increase the Gini coefficient of DVD rentals by 0.0029, which translates to increasing the market share of the top 1% of DVDs by 1.96% and the market share of the top 10% of DVDs by 0.58%. At the same time, the market share of the bottom 1% of DVDs is reduced by 21.29%, while the market share of the bottom 10% of DVDs is reduced by 5.28%. We rule out alternative explanations using a variety of long tail metrics, capturing movie format/distribution channel interaction and customer heterogeneity, while making use of instrumental variables.

Many markets have traditionally been dominated by a few best-selling products, and this is also the case for the health care industry. However, we do not know whether the market will be more or less concentrated when health care services are delivered online (known as E-consultation), nor do we know how to reduce the concentration of the E-consultation market. The aim of this study was to investigate the concentration of the E-consultation market and how to reduce its concentration through information disclosure mechanisms (online reputation and self-representation). We employed a secondary data econometric analysis using transaction data obtained from an E-consultation Website (haodf.com) for three diseases (infantile pneumonia, diabetes, and pancreatic cancer) from 2008 to 2015. We included 2439 doctors in the analysis. The E-consultation market largely follows the 20/80 principle, namely that approximately 80% of orders are fulfilled by nearly 20% of doctors. This is much higher than the offline health care market. Meanwhile, the market served by doctors with strong online reputations (beta=0.207, P<.001) or strong online self-representation (beta=0.386, P<.001) is less concentrated. When health care services are delivered online, the market will be more concentrated (known as the \"Superstar\" effect), indicating poor service efficiency for society as a whole. To reduce market concentration, E-consultation websites should provide important design elements such as ratings of doctors (user feedback), articles contributed by doctors, and free consultation services (online representation). A possible and important way to reduce the market concentration of the E-consultation market is to accumulate enough highly rated or highly self-represented doctors.

A growing concern about the consumer behavior in Internet economy has spurred the study of Material Flow, resulting in a unique type of consumer behavioral analysis. This research proposes an enhanced conceptual model for Personalized Material Flow Services for consumer behavior. In the era of Internet information technology, customer’s taste tends to be personalized for their market demand. It is observed that there are number of “Long Tail” phenomena in several successful e-commerce business cases. However, the Long Tail phenomenon is an open question for our research in terms of its role in e-commerce marketing. In the proposed model-X-Party Personalized Material Flow Services, three elements are discussed. They are “providing”, “locating” and “obtaining” based on X-Party Material Flow theory for which the concept of virtual collector, information filter and Material Flow coordinator are discussed. Business examples of Amazon, Dangdang and Taobao are used to analyze the elements of the virtual collector, information filter and Material Flow coordinator of the Personalized Material Flow Service system.

Colonization of gut microbiomes during early life can shape metabolism and immunity of adult animals. However, most data are derived from antibiotic‐treated or germ‐free laboratory mammals. Furthermore, few studies have explored how microbial colonization during critical windows influences a suite of other fitness‐related traits in wild animals. This study tested whether hatching constitutes a critical developmental window for gut microbiome colonization in wild‐caught amphibians and whether perturbations to gut microbiota at hatching shape fitness‐related traits of larval growth, metabolism, metamorphosis and disease susceptibility. We sterilized wood frog eggs and then inoculated them with microbes from differing sources, including from another species (bullfrogs) that differ in disease resistance and life history. We measured development, growth and metabolic rates through metamorphosis among individuals from each microbial treatment. A separate group was exposed to an LD50 dose of ranavirus—an emerging disease—to test for microbiome effects on disease susceptibility. We also quantified rates of deformities to test for microbial treatment effects on overall health. Manipulation of microbiota on eggs altered the trajectory of gut microbiome communities across larval ontogeny, though disruption appeared to be transitory. While microbiome structure converged among the treatments by metamorphosis, the effects of disruption on host phenotypes persisted. Larvae inoculated with the bullfrog gut microbiota exhibited accelerated growth and development rates compared to controls. By contrast, sterilized larvae maintained in sterile water for several days after hatching exhibited greater disruption to their gut microbiota across ontogeny, as well as altered metabolism, more tail deformities, and were more likely to die when exposed to an LD50 dose of ranavirus compared to the other treatments. These results suggest perturbations to the microbiota during critical developmental windows can alter the trajectory of the gut microbiome, and have long‐term effects on fitness‐related traits in larval amphibians. These results suggest that explicit tests of how changes in the composition and abundance of the microbial community shape phenotypes across ontogeny in amphibians could shed light on host–microbe interactions in wildlife, as well as inform conservation efforts to mitigate emerging diseases. This study shows that hatching is apparently a critical developmental window for bacterial colonization of larval amphibian guts. Perturbation at hatching alters the trajectory of gut microbiomes across ontogeny and shapes host phenotypes. Altered gut microbiota influenced larval amphibian growth, development, metabolism, morphological asymmetry and susceptibility to an emerging disease.

In spite of European legislation attempting to limit this practice, tail docking is nowadays the only preventive measure against tail biting which is widely adopted by farmers. Docking consists in amputating, usually without anaesthesia or analgesia, the distal part of the tail, in order to reduce its attractiveness and to sensitize it, increasing avoidance behaviour in the bitten pig. Tail docking results in both acute and chronic effects on pig welfare, and its effectiveness in preventing tail biting is limited, since it reduces the symptoms of a behavioural disorder, but does not address the underlying causes. The aim of the present paper is to review the available literature on the effects of tail docking on swine welfare. Although from a practical standpoint the welfare risks arising from tail docking may appear to be negligible compared to those arising during and after tail biting outbreaks, it should be considered that, apart from acute physiological and behavioural responses, tail docking may also elicit long-term effects on weight gain, tail stump sensitivity and animal freedom to express their normal behaviour. Such chronic effects have been poorly investigated so far. Besides, studies evaluating the effectiveness of anaesthetics or analgesic treatments are often conflicting. Within this framework, further research is recommended in order to reduce the acute and chronic pain and discomfort experienced by the animals, until preventive measures (e.g., environmental enrichment, stocking densities) are broadly adopted to prevent tail biting.

Chlorpyrifos [ O , O -diethyl- O -(3,5,6-trichloro-2-pyridyl)phosphorothioate] is a widely used non-systemic organophosphorus insecticide frequently detected in surface waters around the world. The goal of this study is to evaluate the acute and chronic effects of this insecticide on Rana dalmatina tadpoles. To assess the sensitivity of this species, the LC50 value (i.e. the concentration at which 50% of tadpoles die) was determined after 96 h. Our results showed that 5.174 mg L −1 chlorpyrifos caused 50% mortality in tadpoles at Gosner stage 25. Chronic toxicity tests were also conducted to evaluate the sublethal effects of chlorpyrifos; tadpoles were exposed to three ecologically relevant concentrations (0.025, 0.05 and 0.1 mg L −1 ) in static renewal tests from Gosner stage 25 (tadpoles shortly after hatching) until completed metamorphosis (Gosner stage 46). No significant reduction was observed in survival, larval growth (mass), snout–vent length, stage development or number metamorphosed. In contrast, chlorpyrifos exhibited significant chronic toxic effects on larval development, manifested as the appearance of abnormalities, including tail flexure, skeletal and muscle defects in later stages of development in tadpoles exposed to all tested concentrations. We also evaluated the chronic effects of chlorpyrifos on gill morphology and ultrastructure. Tadpoles were sacrificed after 8 days and 30 days of exposure. Observations by both scanning (SEM) and transmission electron microscopy (TEM) showed considerable morphological and ultrastructural changes. The main gill effects recorded were mucous secretion, epithelium detachment and a degeneration phenomenon. Comparing these results with our previous findings, we demonstrate that the first effect of chlorpyrifos on R. dalmatina is gill alteration, thus supporting the role of a morphological approach in toxicological studies.

Methamphetamine (METH) has well-documented long-term effects on the brain, including increased psychomotor activity and behavioral sensitization. However, its immediate effects on the brain’s reward system following acute exposure, which may contribute to the development of addiction, are less understood. This study aimed to investigate the effects of acute METH on brain oscillations in the nucleus accumbens of C57BL/6 mice. Mice in the METH group received 5 mg/kg of METH for 5 days during the conditioning phase, followed by an 8-day abstinence period. Afterward, they underwent a 6-minute tail suspension test and were given a 1 mg/kg METH challenge. Local field potential (LFP) data were analyzed for percent total power, mean frequency indices, and phase-amplitude coupling (PAC) to assess the neural effects of METH exposure across these phases. A reduction in theta power was observed across the conditioning, abstinence, and challenge phases of METH exposure. The subsequent METH challenge enhanced gamma oscillations, and PAC analysis revealed a consistent theta-gamma coupling index during both the METH administration and challenge phases. It highlights the sensitivity of the reward system to intense, short-term drug exposure, providing new insights into how acute neural stimulation may contribute to the development of addictive behaviors, reinforcing the brain’s vulnerability to drug-induced changes in neural circuitry. Highlights Acute METH administration induced theta reduction and gamma promotion in the nucleus accumbens. METH abstinent for 8 days induced theta reduction in the nucleus accumbens. The low-dose METH challenge led to a reduction in theta power and an increase in gamma power within the nucleus accumbens. Both METH administration and the METH challenge decreased the maximal phase-amplitude coupling (PAC) index but increased the theta-high gamma coupling. METH abstinent for 8 days producing mean power frequency (MPF) shift during immobility time in TST.

The fin is known to play an important role in swimming for many adult fish, including zebrafish. Zebrafish fins consist of paired pectoral and pelvic with unpaired dorsal, anal, and caudal tail fins with specific functions in fish locomotion. However, there was no study comparing the behavior effects caused by the absence of each fin. We amputated each fin of zebrafish and evaluated their behavior performance in the 3D locomotion test using fractal dimension and entropy analyses. Afterward, the behavior recovery after the tail fin amputation was also evaluated, together with the fin regeneration process to study their relationship. Finally, we conducted a further study to confirm whether the observed behavior alterations were from pain elicited by fin amputation procedure or not by using lidocaine, a pain-relieving drug. Amputation in the caudal fin resulted in the most pronounced behavior alterations, especially in their movement complexity. Furthermore, we also found that their behavior was fully recovered before the caudal fin was fully regenerated, indicating that these behavioral changes were not majorly due to a mechanical change in tail length; instead, they may come from pain elicited from the fin amputation, since treatment with lidocaine could ameliorate the behavioral effects after the amputation procedure. However, lidocaine did not accelerate the behavior recovery process; instead, it caused the fishes to display some slight side effects. This study highlights the potential moderate severity of fin amputation in zebrafish and the importance of analgesia usage. However, side effects may occur and need to be considered since fin amputation is routinely conducted for various research, especially genomic screening.

In the short term, parental presence while a human infant is in pain buffers the immediate pain responses, although emerging evidence suggests repeated social buffering of pain may have untoward long-term effects. To explore the short- and long-term impacts of social buffering of pain, we first measured the infant rat pup's [postnatal day (PN) 8, or 12] response to mild tail shock with the mother present compared to shock alone or no shock. Shock with the mother reduced pain-related behavioral activation and USVs of pups at both ages and reduced Fos expression in the periaqueductal gray, hypothalamic paraventricular nucleus, and the amygdala at PN12 only. At PN12, shock with the mother compared to shock alone differentially regulated expression of several hundred genes related to G-protein-coupled receptors (GPCRs) and neural development, whereas PN8 pups showed a less robust and less coherent expression pattern. In a second set of experiments, pups were exposed to daily repeated Shock-mother pairings (or controls) at PN5-9 or PN10-14 (during and after pain sensitive period, respectively) and long-term outcome assessed in adults. Shock+mother pairing at PN5-9 reduced adult carrageenan-induced thermal hyperalgesia and reduced Fos expression, but PN10-14 pairings had minimal impact. The effect of infant treatment on adult affective behavior showed a complex treatment by age dependent effect. Adult social behavior was decreased following Shock+mother pairings at both PN5-9 and PN10-14, whereas shock alone had no effect. Adult fear responses to a predator odor were decreased only by PN10-14 treatment and the infant Shock alone and Shock+mother did not differ. Overall, integrating these results into our understanding of long-term programming by repeated infant pain experiences, the data suggest that pain experienced within a social context impacts infant neurobehavioral responses and initiates an altered developmental trajectory of pain and affect processing that diverges from experiencing pain alone.