Path planning is a key research issue in the field of unmanned aerial vehicle (UAV) applications. In practical applications, multi-objective path planning is usually required for multi-UAVs, so this paper proposes the improved balanced artificial bee colony (IB-ABC) algorithm to optimize multi-objective path planning. The algorithm adopts the ABC algorithm that emphasizes the global search capability, which is based on iterative feedback information. It uses single-element points, multi-element points, and iteration constraints to optimize the strategies of employed bees, follower bees, and scout bees, respectively. In terms of time and priority, simulation experiments prove that the IB-ABC algorithm can balance local and global search capabilities, accelerate the speed of convergence, and realize multi-UAV path planning in complex mountain environments.

Due to the lack of research between the inner layers in the structure of colonic mucous and the metabolism of fatty acid in the constipation model, we aim to determine the changes in the mucous phenotype of the colonic glycocalyx and the microbial community structure following treatment with Rhubarb extract in our research. The constipation and treatment models are generated using adult male C57BL/6N mice. We perform light microscopy and transmission electron microscopy (TEM) to detect a Muc2-rich inner mucus layer attached to mice colon under different conditions. In addition, 16S rDNA sequencing is performed to examine the intestinal flora. According to TEM images, we demonstrate that Rhubarb can promote mucin secretion and find direct evidence of dendritic structure-linked mucus structures with its assembly into a lamellar network in a pore size distribution in the isolated colon section. Moreover, the diversity of intestinal flora has noticeable changes in constipated mice. The present study characterizes a dendritic structure and persistent cross-links have significant changes accompanied by the alteration of intestinal flora in feces in models of constipation and pretreatment with Rhubarb extract.

Methomyl is a broad-spectrum carbamate insecticide that has a variety of toxic effects on humans and animals. However, there have been no studies on the toxicity of methomyl in female mammalian oocytes. This study investigated the toxic effects of environmental oestrogen methomyl exposure on mouse oocyte maturation and its possible mechanisms. Our results indicated that methomyl exposure inhibited polar body extrusion in mouse oocytes. Compared with that in the control group, in the methomyl treatment group, superoxide anion free radicals in oocytes were significantly increased. In addition, the mitochondrial membrane potential of metaphase II stage oocytes in the methomyl treatment group was significantly decreased, resulting in reduced mouse oocyte quality. After 8.5 h of exposure to methomyl, metaphase I stage mouse oocytes displayed an abnormal spindle morphology. mRNA expression of the pro-apoptotic genes Bax and Caspase-3 in methomyl-treated oocytes increased, which confirmed the apoptosis. Collectively, our results indicated that mouse oocyte maturation is defective after methomyl treatment at least through disruption of spindle morphology, mitochondrial function and by induction of oxidative stress.

We present a theoretical study of mode evolution in high-power distributed side-coupled cladding-pumped (DSCCP) fiber amplifiers. A semi-analytical model taking the side-pumping schemes, transverse mode competition, and stimulated thermal Rayleigh scattering into consideration has been built, which can model the static and dynamic mode evolution in high-power DSCCP fiber amplifiers. The mode evolution behavior has been investigated with variation of the fiber amplifier parameters, such as the pump power distribution, the length of the DSCCP fiber, the averaged coupling coefficient, the number of the pump cores and the arrangement of the pump cores. Interestingly, it revealed that static mode evolution induced by transverse mode competition is different from the dynamic evolution induced by stimulated thermal Rayleigh scattering. This shows that the high-order mode experiences a slightly higher gain in DSCCP fiber amplifiers, but the mode instability thresholds for DSCCP fiber amplifiers are higher than those for their end-coupled counterparts. By increasing the pump core number and reducing the averaged coupling coefficient, the mode instability threshold can be increased, which indicates that DSCCP fibers can provide additional mitigation strategies of dynamic mode instability.

A kind of tapered segmented cladding fiber (T-SCF) with large mode area (LMA) is proposed, and the mode and amplification characteristics of T-SCFs with concave, linear, and convex tapered structures are investigated based on finite-element method (FEM) and few-mode steady-state rate equation. Simulation results indicate that the concave tapered structure can introduce high loss for high-order modes (HOMs) that is advantageous to achieve single-mode operation, whereas the convex tapered structure provides large effective mode area that can help to mitigate nonlinear effects. Meanwhile, the small-to-large amplification scheme shows further advantages on stripping off HOMs, and the large-to-small amplification scheme decreases the heat load density induced by the high-power pump. Moreover, single-mode propagation performance, effective mode area, and heat load density of the T-SCF are superior to those of tapered step index fiber (T-SIF). These theoretical model and numerical results can provide instructive suggestions for designing high-power fiber lasers and amplifiers.

The objective of this study was to analyze differences in birth weight and overweight/obesity in a Shanghai twin cohort. We also wanted to study their association and explore possible risk factors for the discordance of overweight/obesity within twins. This was an internal case–control study designed for twins. The 2012 Shanghai Twin Registration System baseline survey data of a total of 3417 twin pairs were statistically analyzed using SPSS22 software. Results show that the body mass index (BMI) of the Shanghai twin population increased with age. Twins with a high birth weight had a higher BMI and a higher rate of overweight and obesity; 0- to 6-year-old twins, male twins and dizygotic (DZ) twins had higher rates of overweight/obesity than other groups. The greater the discordant birth weight rate of twins, the more obvious the difference in BMI (p < .05). There was a significant difference in overweight/obesity between twins with a relative difference of birth weight ≥15% in DZ twins (p < .05). DZ twins, male twins and 0- to 6-year-old twins were more likely to be discordant in overweight/obese than others. The discordant birth weight within twins was not a risk factor for discordant overweight/obesity. However, attention should be paid to childhood obesity, and appropriate interventions should be made at the appropriate time. Genetics may play an important role in the occurrence and development of overweight/obesity. In conclusion, discordant growth and development in the uterus early in life may not lead to discordant weight development in the future.

This study aimed to evaluate to what extent the different interval times between trophectoderm (TE) biopsy and vitrification influence the clinical outcomes in preimplantation genetic testing (PGT) cycles. Patients who underwent frozen embryo transfer (FET) after PGT between 2015 and 2019 were recruited. In total, 297 cycles with single day 5 euploid blastocyst transfer were included. These cycles were divided into three groups according to the interval times: <1 h group, 1–2 h group, and ≥2 h group. Blastocyst survival, clinical pregnancy, miscarriage, and ongoing pregnancy rates were compared. The results showed that, in PGT-SR cycles, survival rate in the ≥2 h group (96.72%) was significantly lower than in the <1 h group (100%, P = 0.047). The clinical pregnancy rate in the ≥2 h group was 55.93%, significantly lower than in the <1 h group (74.26%, P = 0.017). The ongoing pregnancy rates in the 1–2 h group and the ≥2 h group were 48.28% and 47.46%, respectively, significantly lower than that in the <1 h group (67.33%, P < 0.05). The miscarriage rate in the 1–2 h group was 18.42%, significantly higher than that in the <1 h group (5.33%, P = 0.027). In PGT-A cycles, the clinical pregnancy and ongoing pregnancy rates in the <1 h group were 67.44% and 53.49%, respectively, higher than that in the 1–2 h group (52.94%, 47.06%, P > 0.05) and the ≥2 h group (52.63%, 36.84%, P > 0.05). In conclusion, vitrification of blastocysts beyond 1 h after biopsy significantly influences embryo survival and clinical outcomes and is therefore not recommended.

To understand the characteristics and influencing factors related to cluster infections in Jiangsu Province, China, we investigated case reports to explore transmission dynamics and influencing factors of scales of cluster infection. The effectiveness of interventions was assessed by changes in the time-dependent reproductive number (Rt). From 25th January to 29th February, Jiangsu Province reported a total of 134 clusters involving 617 cases. Household clusters accounted for 79.85% of the total. The time interval from onset to report of index cases was 8 days, which was longer than that of secondary cases (4 days) (χ2 = 22.763, P < 0.001) and had a relationship with the number of secondary cases (the correlation coefficient (r) = 0.193, P = 0.040). The average interval from onset to report was different between family cluster cases (4 days) and community cluster cases (7 days) (χ2 = 28.072, P < 0.001). The average time interval from onset to isolation of patients with secondary infection (5 days) was longer than that of patients without secondary infection (3 days) (F = 9.761, P = 0.002). Asymptomatic patients and non-familial clusters had impacts on the size of the clusters. The average reduction in the Rt value in family clusters (26.00%, 0.26 ± 0.22) was lower than that in other clusters (37.00%, 0.37 ± 0.26) (F = 4.400, P = 0.039). Early detection of asymptomatic patients and early reports of non-family clusters can effectively weaken cluster infections.

A multidisciplinary fieldwork and research project was recently begun at the Yangshang site (220–140 ka), a late Early Paleolithic locale in the western Chinese Loess Plateau. 1696 lithic artifacts and 337 faunal remains were recovered during the excavation. Sedimentological and paleoenvironmental investigations indicate the site preserves a relatively long and minimally disturbed archaeological sequence associated with paleoenvironmental changes during MIS 7–6. A detailed techno-typological analysis of Yangshang's lithic assemblages was undertaken to examine the influence of glacial cycles on late Middle Pleistocene hominin technological strategies in the western Chinese Loess Plateau. The results show that while the Yangshang site is dominated by quartz-based core/flake assemblages typical of most Early Paleolithic sites in North China, the lithic assemblages provide evidence that different provisioning systems existed during the penultimate glaciation. We argue that these shifts reflect changes in land use and mobility that were tied to climate change. Our results suggest that theoretically informed statistical analyses of so-called unchanging and crude lithic technology can yield meaningful evidence for behavioral shifts.

Primary liver cancer is the third leading cause of cancer-related death worldwide. Most patients are diagnosed at late stages with poor prognosis; thus, identification of modifiable risk factors for primary prevention of liver cancer is urgently needed. The well-established risk factors of liver cancer include chronic infection with hepatitis B virus (HBV) or hepatitis C virus (HCV), heavy alcohol consumption, metabolic diseases such as obesity and diabetes, and aflatoxin exposure. However, a large proportion of cancer cases worldwide cannot be explained by current known risk factors. Dietary factors have been suspected as important, but dietary aetiology of liver cancer remains poorly understood. In this review, we summarised and evaluated the observational studies of diet including single nutrients, food and food groups, as well as dietary patterns with the risk of developing liver cancer. Although there are large knowledge gaps between diet and liver cancer risk, current epidemiological evidence supports an important role of diet in liver cancer development. For example, exposure to aflatoxin, heavy alcohol drinking and possibly dairy product (not including yogurt) intake increase, while intake of coffee, fish and tea, light-to-moderate alcohol drinking and several healthy dietary patterns (e.g. Alternative Healthy Eating Index) may decrease liver cancer risk. Future studies with large sample size and accurate diet measurement are warranted and need to consider issues such as the possible aetiological heterogeneity between liver cancer subtypes, the influence of chronic HBV or HCV infection, the high-risk populations (e.g. cirrhosis) and a potential interplay with host gut microbiota or genetic variations.

In recent years, there have been a significant influenza activity and emerging influenza strains in China, resulting in an increasing number of influenza virus infections and leading to public health concerns. The aims of this study were to identify the epidemiological and aetiological characteristics of influenza and establish seasonal autoregressive integrated moving average (SARIMA) models for forecasting the percentage of visits for influenza-like illness (ILI%) in urban and rural areas of Shenyang. Influenza surveillance data were obtained for ILI cases and influenza virus positivity from 18 sentinel hospitals. The SARIMA models were constructed to predict ILI% for January–December 2019. During 2010–2018, the influenza activity was higher in urban than in rural areas. The age distribution of ILI cases showed the highest rate in young children aged 0–4 years. Seasonal A/H3N2, influenza B virus and pandemic A/H1N1 continuously co-circulated in winter and spring seasons. In addition, the SARIMA (0, 1, 0) (0, 1, 2)12 model for the urban area and the SARIMA (1, 1, 1) (1, 1, 0)12 model for the rural area were appropriate for predicting influenza incidence. Our findings suggested that there were regional and seasonal distinctions of ILI activity in Shenyang. A co-epidemic pattern of influenza strains was evident in terms of seasonal influenza activity. Young children were more susceptible to influenza virus infection than adults. These results provide a reference for future influenza prevention and control strategies in the study area.

Trypophloeus klimeschi Eggers (Coleoptera: Curculionidae: Scolytinae) was first discovered in China in 2003, and it exhibits strong species specificity to Populus alba var. pyramidalis Bunge (Salicaceae). To screen plant volatile compounds for monitoring and trapping T. klimeschi, the electroantennogram responses of adult T. klimeschi to eight plant volatiles, including nonanal, 2-methylbutanal, decanal, 2-hydroxybenzaldehyde, (Z)-3-hexen-1-ol benzoate, methyl benzoate, methyl salicylate, and geraniol were tested at various concentrations. Behavioural responses of female and male adults to various concentrations of these eight plant volatiles were also determined using a Y-tube olfactometer. We then tested the effectiveness of these compounds as lures for trapping T. klimeschi in the field. Electroantennogram tests showed that T. klimeschi possesses olfactory sensitivity for eight compounds. Additionally, walking T. klimeschi exhibited attraction to low concentrations (≤ 1 μg/μL) of all eight compounds in Y-tube olfactometer. Field experiment results indicated that baits composed of each volatile compound alone were more attractive to greater numbers of T. klimeschi than the control. The methyl benzoate bait was better attracted by T. klimeschi than other tested volatiles. These results suggest that these compounds could be used in attraction of this stem-boring pest. This study could have important implications for the development of an effective semiochemical-based management tool for T. klimeschi in the field.