Guangxi In China Research Articles

Association Between Urinary Rare Earth Element Levels and Metabolic Syndrome: A Cross-sectional Study in the Minority Population of Guangxi in China.

This study aimed to investigate the association between rare earth elements (REEs) and metabolic syndrome (MetS). We used a cross-sectional design based on the baseline data of the Prospective Cohort Study of Chronic Diseases in Ethnic Minority Natural Population in Guangxi in China. Logistic regression and BKMR models were employed to evaluate the association between REEs and risk of MetS. Although REEs were not significantly associated with MetS, certain elements such as La, Pr, and Nd were negatively associated with abdominal obesity, whereas Ce, Pr, Nd, and Dy were positively associated with hypertension. BKMR models suggested a U-shaped relationship between mixed REEs and MetS, with varying effects on abdominal obesity and high blood pressure. This study suggests that exposure to REEs may be associated with a reduced risk of abdominal obesity and an increased risk of high blood pressure.

Five new species of the genus Phlugiolopsis Zeuner, 1940 (Tettigoniidae: Meconematinae) from China

This paper reports five new species of Phlugiolopsis Zeuner, 1940 from Sichuan, Yunnan and Guangxi in China, i.e., Phlugiolopsis luojishanensis sp. nov., Phlugiolopsis lata sp. nov., Phlugiolopsis rongshuiensis sp. nov., Phlugiolopsis acuta sp. nov. and Phlugiolopsis daweishanensis sp. nov. We present a redescription of the male of Phlugiolopsis punctata Wang, Li & Liu, 2012, describe the female of Phlugiolopsis punctata Wang, Li & Liu, 2012 and the male of Phlugiolopsis pentagonis Bian, Shi & Chang, 2013 for the first time. In addition, images illustrating the morphology of these species and seven previously described species are provided. The distribution map of the genus Phlugiolopsis from China is also provided.

Prediction on the changes in potential suitable areas for mangroves along the coast of Guangxi and the threat from Spartina alterniflora invasion.

As one of the important blue carbon pools in tropical and subtropical intertidal zones, mangroves are widely distributed along the coast of Guangxi in China. To deeply explore the variations of potential suitable habitats for mangroves in China under the background of climate change, based on remote sensing interpretation data of coastal wetlands in Guangxi, global marine environment and bioclimatic environment data in 2021, we constructed a maximum entropy habitat distribution model to simulate the spatial distribution of potential suitable areas for mangroves and the invasive species, Spartina alterniflora, along the coast of Guangxi, and predicted the patterns under extreme climate change scenarios (SSP5-8.5). The results showed that the interpreted area of mangrove forests along the coastline of Guangxi was 9136.7 hm2 in 2021, while the predicted area of potential suitable habitat area was 55955.9 hm2. Current distribution area of mangroves had basically covered its potential high suitability area and nearly 10% of the moderate suitability area. The current area of S. alterniflora was 1320.4 hm2, and the predicted area of potential high suitability area was twice of current area, indicating that there was still a large proportion of high suitability area that was not occupied by S. alterniflora. The most important environmental factors driving the distribution of potential habitats in mangroves were offshore Euclidean distance (62.2%), terrain deviation index (8.7%), average sea surface temperature in the hottest season (6.1%), and seabed terrain elevation (5.6%). The contribution of geographical conditions on mangrove distribution was predominant. Under the climate change scenario (SSP5-8.5), potential suitable area for mangroves would increase by 5.3%, while that for S. alterniflora would decrease by 3.1%. The overlapping proportion of the potential suitable area for mangroves and S. alterniflora was similar under current and SSP5-8.5 scenarios, being 15.2% and 14.5%, respectively. In the future, it is necessary to strengthen the protection and ecological restoration of mangroves along the coast of Guangxi and there is great challenge for preventing further invasion of S. alterniflora.

Assessing the Performance of Water Vapor Products from ERA5 and MERRA-2 during Heavy Rainfall in the Guangxi Region of China

Precipitable water vapor (PWV) is a crucial factor in regulating the Earth’s climate. Moreover, it demonstrates a robust correlation with precipitation. Situated in a region known for the generation and development of tropical cyclones, Guangxi in China is highly susceptible to floods triggered via intense rainfall. The atmospheric water vapor in this area displays prominent spatiotemporal features, thus posing challenges for precipitation forecasting. The water vapor products within the MERRA-2 and ERA5 reanalysis datasets present an opportunity to overcome constraints associated with low spatiotemporal resolution. In this study, the PWV data derived from GNSS and meteorological measurements in Guangxi from 2016 to 2018 were used to evaluate the accuracy of MERRA-2 and ERA5 water vapor products and their relationship with water vapor variations during extreme rainfall. Using GNSS PWV as a reference, the average bias of MERRA-2 PWV and ERA5 PWV for heavy rainfall was −0.22 mm and 1.84 mm, respectively, with average RMSE values of 3.72 mm and 3.31 mm. For severe rainfall, the average bias of MERRA-2 PWV and ERA5 PWV was −0.14 mm and 2.92 mm, respectively, with average RMSE values of 4.28 mm and 4.01 mm. During heavy rainfall days from Days 178 to 184 in 2017, the average bias of MERRA-2 PWV and ERA5 PWV was 0.92 mm and 2.42 mm, respectively, with average RMSE values of 4.04 mm and 3.40 mm. The accuracy was highest at the Guiping and Hechi stations and lowest at the Hezhou and Rongshui stations. Furthermore, when comparing MERRA-2/ERA5 PWV with GNSS PWV and actual precipitation, the trends in the variations of MERRA-2/ERA5 PWV were generally consistent with GNSS PWV and aligned with the increasing or decreasing trends of actual precipitation. In addition, ERA5 PWV exhibited high accuracy. Before the onset of heavy rainfall, PWV has a sharp surge. During heavy rainfall, PWV reaches its peak value. Subsequently, after the cessation of heavy rainfall, PWV tends to stabilize. Therefore, the reanalysis data of PWV can effectively reveal significant changes in water vapor and actual precipitation during periods of heavy rainfall in the Guangxi region.

Future habitat changes of Bactrocera minax Enderlein along the Yangtze River Basin using the optimal MaxEnt model.

Bactrocera minax (Enderlein, 1920) (Diptera: Tephritidae) is a destructive citrus pest. It is mainly distributed throughout Shaanxi, Sichuan, Chongqing, Guizhou, Yunnan, Hubei, Hunan, and Guangxi in China and is considered to be a second-class pest that is prohibited from entering that country. Climate change, new farming techniques, and increased international trade has caused the habitable area of this pest to gradually expand. Understanding the suitable habitats of B. minax under future climate scenarios may be crucial to reveal the expansion pattern of the insect and develop corresponding prevention strategies in China. Using on the current 199 distribution points and 11 environmental variables for B. minax, we chose the optimal MaxEnt model to screen the dominant factors that affect the distribution of B. minax and to predict the potential future distribution of B. minax in China under two shared socio-economic pathways (SSP1-2.6, SSP5-8.5). The current habitat of B. minax is located at 24.1-34.6°N and 101.1-122.9°E, which encompasses the provinces of Guizhou, Sichuan, Hubei, Hunan, Chongqing, and Yunnan (21.64 × 104 km2). Under future climate scenarios, the potential suitable habitat for B. minax may expand significantly toward the lower-middle reaches of the Yangtze River. The land coverage of highly suitable habitats may increase from 21.64 × 104 km2 to 26.35 × 104 × 104 km2 (2050s, SSP5-8.5) ~ 33.51 × 104 km2 (2090s, SSP5-8.5). This expansion area accounts for 29% (2050s, SSP1-2.6) to 34.83% (2090s, SSP1-2.6) of the current habitat. The center of the suitable habitat was predicted to expand towards the northeast, and the scenario with a stronger radiative force corresponded to a more marked movement of the center toward higher latitudes. A jackknife test showed that the dominant variables affecting the distribution of B. minax were the mean temperature of the driest quarter (bio9), the annual precipitation (bio12), the mean diurnal range (bio2), the temperature annual range (bio7), and the altitude (alt). Currently, it is possible for B. minax to expand its damaging presence. Regions with appropriate climate conditions and distribution of host plants may become potential habitats for the insects, and local authorities should strengthen their detection and prevention strategies. Climate changes in the future may promote the survival and expansion of B. minax species in China, which is represented by the significant increase of suitable habitats toward regions of high altitudes and latitudes across all directions but with some shrinkage in the east and west sides.

First report of anthracnose caused by Colletotrichum siamense on Illicium verum in China.

Aniseed (Illicium verum) is a woody spice tree that has been grown in China for a long time. Anthracnose is an important disease of aniseed, which can cause severe leaf drop. In Sep. 2020, severe anthracnose was observed in Shanglin (23°35'5"N, 108°19'51"E), Nanning, Guangxi in China, and the incidence was 85%. The symptoms at the early stage were small, round and watery, then became larger and gradually turned brown. The acervuli would appear at the later stage, and contain many conidia. Leaves with disease were randomly sampled from 10 plants, and were cut into small rectangular pieces of 0.5×1 cm, and disinfected with 75% alcohol 1 min, with 0.1% HgCl2 3 min. After washing with sterile water 3 times, they were placed onto potato dextrose agar (PDA) medium and incubated at 25°C for 5 days. The average colony growth rate was 11.85 mm/d in 7 days. The colony was white or light gray in the initial stage, with dense aerial mycelium, and the central mycelium of the colony was dark grey in the later stage. Conidia were colorless, single spore, smooth, cylindrical, both ends obtuse, with an average size of 14.95 ± 0.97 μm × 5.46 ± 0.44 μm (n = 100). The conidial appressorium was oval or club-shaped, brown, margin intact, with an average size of 7.83 ± 1.21 μm × 5.82 ± 0.58μm (n = 50). Three strains GXNN02, GXNN03 and GXNN05 were selected for further study. Primer pairs T1/βt2b, ACT512/ACT783, GDF/GDR, CHS1-79F / CHS1-354R and ITS1/ITS4 (Weir et al. 2012) were used to amplify tubulin (TUB), actin (ACT), 3-phosphate glyceraldehyde dehydrogenase (GAPDH), chitinase (CHS1) and the internal transcribed spacers of rDNA (ITS) respectively. BLASTn searches showed that the TUB (ON619861-63 ), ACT (ON619852-54), GAPDH (ON619855-57), CHS1 (ON619858-60) and ITS (ON573028-30) sequences had the highest similarity to Colletotrichum siamense with up to 99% (699/702, 676/679, 699/702) identity for TUB (JX010404.1); 99% (281/282, 253/254, 249/250) identity for ACT (JX009518.1); 99% (275/277, 275/277, 239/241) identity for GAPDH (JX009924.1); 99% (296/299, 296/299, 259/262) identity for CHS1 (JX009865.1); up to 99% (527/530, 485/487, 527/530) identity for ITS (JX010171.1) of ex-type ICMP 18578. A ML tree was constructed by combining 5 sequenced loci, and three isolates clustered in the C. siamense clade with 94% bootstrap support. Therefore, combined with the morphological characteristics, the pathogens were identified as C. siamense. In a pathogenicity test, these three isolates were tested on 9 healthy aniseed seedlings with at least 10 leaves, and 3 seedlings as control. The leaves were surface disinfected with 75% alcohol, and then wiped with sterilized water three times. Holes were made near the edge of the leaves and were sprayed with conidial solution (6×106 spores/mL) in test groups, and use sterilized water as control. Then the leaves were sealed inside a plastic bag for 48 h to retain moisture. Brown spot and black acervuli, similar to the symptoms in the field, were observed on the leaves in test groups within 10-15 days. No symptoms were observed on the negative control leaves. The pathogens were reisolated from the treated infected leaves and were identified as C. siamense, thus fulfilling Koch's postulates. The pathogenicity test was confirmed by repeating in triplicate. The isolation frequency of C. siamense in our samples was 82.50%. To our knowledge, this is the first report of C. siamense in China. Further research on the occurrence of the disease will help prevent the spread of the disease.

Association between the AKT1 single nucleotide polymorphism (rs2498786, rs2494752 and rs5811155) and microscopic polyangiitis risk in a Chinese population

Microscopic polyangiitis (MPA) is an autoimmune disease, characterized by ANCA in blood and necrotizing inflammation of small and medium-sized vessels, one of the three clinical phenotypes of ANCA-associated vasculitis (AAV). Autophagy has been confirmed to be involved in the pathogenesis of AAV. AKT1 is one of the autophagy-regulated proteins. Its single nucleotide polymorphisms (SNPs) are associated with multiple immune-related diseases, but there are rarely studies in AAV. The incidence rate of AAV has a notable geographic difference, and MPA is predominant in China. The aim of this study was to investigate the association between AKT1 SNP and MPA risk. Genotypes of 8 loci in AKT1 were evaluated by multiplex polymerase chain reaction (PCR) and high-throughput sequencing in 416 people, including 208 MPA patients and 208 healthy volunteers from Guangxi in China. Additionally, data of 387 healthy volunteers from China were obtained from the 1000Genomes Project on public database. Differences were observed between the loci (rs2498786, rs2494752, and rs5811155) genotypes in AKT1 and MPA risk (P = 7.0 × 10–4, P = 3.0 × 10–4, and P = 5.9 × 10–5, respectively). A negative association was detected in the Dominant model (P = 1.2 × 10–3, P = 2.0 × 10–4 and P = 3.6 × 10–5, respectively). A haplotype (G-G-T) was associated with MPA risk negatively (P = 7.0 × 10–4). This study suggests that alleles (rs2498786 G, rs2494752 G and rs5811155 insT) are protective factors for MPA and alleles (rs2494752 G and rs5811155 insT) for MPO-ANCA in patients with MPA. There is a haplotype (G-G-T), which is a protective factor for MPA. It suggests that the role of AKT1 in MPA/AAV needs further study to provide more intervention targets for MPA/AAV.

First report of branch blight caused by Diaporthe ueckerae on Eucalyptus citriodora in China.

Eucalyptus citriodora is a wood and oil dual-purpose tree with strong growth adaptability and high ornamental value. Recent years, it has been widely planted in Guangxi in China. In Nov. 2021, branch blight was found to be widespread on E. citriodora in Qinzhou in China (21°57'57"N, 108°42'6"E). The occurrence area was over 7000 m2, and the disease incidence was 23% (23/100). Twigs were withered in most of infected plants, and only top branch died in few plants. The lesions started from branch tips, then expanded and caused 5-20 cm branches died in final. The lesions were tiny and brown at early stage, then turned dark brown or black. Ten diseased branches were sampled randomly in field and were cut into 1 cm pieces. After surface disinfecting with 75% ethanol for 3 min, 0.1% HgCl2 for 5 min, washing with sterile water three times, samples were placed onto Potato Dextrose Agar (PDA) medium. Hyphae appeared after incubating for 5 days at 28 ℃. The diameter of colonies reached 64-71 mm after 7 days incubation. The colonies were white and felt-like, and then turned yellowish gradually with flourish aerial hyphae. Two weeks later, pycnidia appeared, which were nearly spherical, initial pale yellow and later black. Sometimes secretions overflowed from the aperture on pycnidia. There were 2 types of conidia (α and β type), which were unicellular and hyaline. The α type was spindle to ellipse and had 1-2 oil globule, with 5.56±0.50 × 2.67±0.39 μm (n=100) in size. The β type was linear and one end bent in hook shape, with 17.10±2.54 × 1.55±0.32 μm (n=50) in size. Three isolates (LEQZ01, LEQZ02, LEQZ03) were selected for further study. The internal transcribed spacers (ITS) region of rDNA, translation elongation factor 1-α (tef1 α) and β-tubulin (tub2) genes were amplified using primer pairs ITS1/ITS4 (White et al. 1990), EF1-983F/EF1-1567R (Rehner et al. 2005) and Tub1/ Tub2 (Chauhan et al. 2007), respectively. BLASTn searches showed that the ITS (OM339849, ON075781, ON075782), tef1 α (ON093807-ON093809) and tub2 (ON093810-ON093812) sequences had the highest similarity with Diaporthe ueckerae strains, with 99% (543/549, 544/549, 544/549) identity for ITS (NR 147543.1), with 99% (350/351, 353/353, 349/350) identity for tef1 α (KY569388.1), with 99% (754/754, 753/754, 754/754) identity for tub2 (MW514128.1). A neighbor-joining tree constructed by combining 3 sequenced loci. Three isolates clustered in the D. ueckerae clade with 100% bootstrap support. Based on morphological (Yi et al. 2018) and molecular evidences, the pathogen was identified as D. ueckerae. In a pathogenicity test, 20 healthy E. citriodora seedlings were divided into 4 groups. Before inoculation, twigs were surface disinfected with 75% ethanol followed by washing 3 times using sterile water. Tiny artificial wounds at 5 cm below the seedling top were inoculated by hyphae taken from colonies incubated for 7 days at 25 ℃ in the dark, and covered with damp cotton in 1-3 groups (Yi et al. 2018). Yet the wounds were covered with damp cotton in control group. Two days later, wounds started to turn brown in test groups, and symptoms similar to field were obtained after 10 days. But no lesion emerged in control group. Then germs were re-isolated from symptomatic twigs and identified as D. ueckerae following the methods above. To our knowledge, this is the first report of branch blight caused by D. ueckerae on E. citriodora in China. Further researches on disease epidemiology would help to prevent spread to more locations.

Soil nutrient contents and stoichiometry within aggregate size classes varied with tea plantation age and soil depth in southern Guangxi in China

Abstract. Soil ecological stoichiometry offers a tool to explore the distribution, cycling, limitation, and balance of chemical elements in tea plantation ecosystems. This study aimed to explore how soil organic C (OC) and nutrient contents (total N (TN), total P (TP), Ca2+, Mg2+, Fe2+, and Mn2+) as well as their stoichiometric ratios (C/N, C/P, N/P, Ca/Mg, and Fe/Mn) varied with tea plantation age (8, 17, 25, and 43 years) and soil depth (0–10, 10–20, 20–40, and 40–60 cm) within aggregates in southern Guangxi in China. Our results showed that tea plantation age and soil depth significantly affected soil nutrient stoichiometry in different sizes of aggregates. Among different ages of tea plantations, soil OC, TN, and TP contents as well as C/N, C/P, and N/P ratios significantly decreased as the soil depth increased. In addition, soil Ca2+ and Mg2+ contents were significantly lower in the surface soil layer than the deeper soil layer, whereas soil Fe2+ and Mn2+ contents showed opposite trends, and no significant differences were detected in Ca/Mg and Fe/Mn ratios among different soil depths. At the 0–40 cm soil depth, continuous planting of tea corresponded to increases in soil OC, TN, Fe2+, and Mn2+ contents, whereas soil Ca2+ and Mg2+ contents significantly decreased over time. During the process of tea growth, the losses of soil Ca2+ and Mg2+, especially Ca2+ (as indicated by the decrease in the soil Ca/Mg ratio), led to soil acidification, which reduced Fe2+ absorption and enhanced Mn2+ uptake by tea plants (as indicated by the increase in the soil Fe/Mn ratio). In general, tea plantation age affected the variations of soil nutrient contents and stoichiometry, and such effects were more obvious at the 0–40 cm soil depth, in contrast to the 40–60 cm soil depth.

Analysis of the Mineral Compositions of Lateritic Clay in Guangxi and their Influence

In order to study the effect of mineral composition on the physical properties of lateritic clays, the mineral compositions of four kinds of lateritic clay from Guangxi province in China were quantitatively analyzed by means of DTA, XRD, SEM, XRF and total chemical element analysis. On this basis, the variation law of macroscopic physical properties of lateritic clay was analyzed from the perspective of mineralogy. The results show that kaolinite and goethite are the main minerals of lateritic clays from Guangxi in China. The mineral compositions of these four samples are quantitatively and accurately analyzed by Bogue’s method. According to the study on mineral compositions of soil samples, the physical properties of lateritic clay are related to its clay minerals and cemented substances. The liquid limit (LL) or plastic limit (PL) increases with the increase of the ability and content of clay minerals to adsorb water. The lateritic clay is dominated by kaolinite minerals with low adsorption capacity, so the observed boundary water content (LL and PL) of high value of lateritic clays can be explained by the contribution of “inert water” in soil pores. The iron-bonded cement minerals (the form of existence is goethite) in lateritic clay have great influence on the liquid and plastic limits, which decrease linearly with the increase of goethite, whereas the goethite has relatively smaller effect on shrinkage characteristics. It is believed that the shrinkage characteristics of lateritic clay may also be affected by other factors.

Diversity and pathogenicity of Alternaria species associated with the invasive plant Ageratina adenophora and local plants.

Pathogen accumulation after introduction is unavoidable for exotic plants over a long period of time. Therefore, it is important to understand whether plant invasion promotes novel pathogen emergence and increases the risk of pathogen movement among agricultural, horticultural, and wild native plants. In this study, we used multiple gene analysis to characterize the species composition of 104 isolates of Alternaria obtained from the invasive plant Ageratina adenophora and native plants from Yunnan, Hubei, Guizhou, Sichuan, and Guangxi in China. Phylogenetically, these strains were from A. alternata (88.5%), A. gossypina (10.6%) and A. steviae (0.9%). There was a high amount of sharing between strains associated with A. adenophora and with local plants. Pathogenicity tests indicated that most of these Alternaria strains are generalists; the isolates with a wider host range were more virulent to the plant. Woody plants were more resistant to these strains than herbaceous plants and vines. However, the invasive plant A. adenophora was highly sensitive to these strains. Our data are valuable for understanding how A. adenophora invasion impacts the Alternaria species composition of the native plant and whether A. adenophora invasion causes potential disease risks in invaded ecosystems.

Two new species of the genus Endelus Deyrolle, 1864 from China (Coleoptera: Buprestidae)

• Two new species, Endelus ( E .) violaceithorax sp. n. and Endelus ( E .) wangi sp. n. from China, are described and illustrated. • A key to separate Chinese Endelus species is provided. • Endelus ( Kubaniellus ) kareni Kalashian, 1997 are firstly recorded from Guangxi in China. The genus Endelus Deyrolle, 1864 belongs to the subfamily Agrilinae, tribe Aphanisticini. Two new species, E. ( E. ) violaceithorax sp. n. from Hainan Island and E. ( E. ) wangi sp. n. from Guangxi and Yunnan, are herein described and illustrated. A key to separate species of the subgenus Endelus Deyrolle, 1864 from China is provided. www.zoobank.org/urn:lsid:zoobank.org:pub:CF144204-86FB-401D-AF75-B740CCD020DC.

Effects of hydrostatic pressure and temperature on the nonlinear optical properties of semiparabolic plus semi-inverse squared quantum wells* *Project supported by the Natural Science Foundation of China (Grant Nos.11604289, 11804063, and 51971193), the BaGui scholar program of Guangxi Province in China and the Natural Science Foundation of Guangxi in China (Grant No.2016GXNSFBA380017).

In this study, the effects of hydrostatic pressure and temperature on nonlinear optical rectification (OR), second-harmonic generation (SHG), third-harmonic generation (THG) and the linear, nonlinear, and total optical absorption coefficients (OACs) of a semiparabolic plus semi-inverse squared quantum well (QW) are theoretically investigated. The results show that hydrostatic pressure and temperature have significant effects on the optical properties of semiparabolic plus semi-inverse squared QWs, and that the energy levels and magnitudes of the resonant peaks of OR, SHG, THG, and the total OACs vary according to the shape of the limiting potential, the hydrostatic pressure, and the temperature. It is easily seen that the peak positions of the resonant peaks of OR, SHG, THG, and the total OACs in the semiparabolic plus semi-inverse squared QW show a red shift with increasing hydrostatic pressure, but a blue shift with increasing temperature. Therefore, the magnitude and position of the resonant peaks of OR, SHG, THG, and the total OACs can be adjusted by changing the hydrostatic pressure and the temperature, which promise a new degree of freedom in the tunability of various electro-optical devices.

Species of Colletotrichum on bamboos from China

ABSTRACT Twenty-seven Colletotrichum isolates associated with asymptomatic tissues of bamboo (Bambusoideae, Gramineae) were isolated from Anhui, Beijing, and Guangxi in China. Based on multilocus (internal transcribed spacer [ITS], glyceraldehyde-3-phosphate dehydrogenase [GAPDH], chitin synthase [CHS], actin [ACT], beta-tubulin [TUB2]) phylogenetic analyses and morphological characteristics, three species were distinguished, including two novel species, C. bambusicola and C. guangxiense, and one known species, C. metake, which is a first report for China. These species have hitherto only been discovered on Bambusoideae, indicating that they probably have host preference.

COVID-19’s influence on the credit risks and enterprise innovation of the Guangxi manufacturing——Based on the measure of KMV model

The paper used the KMV model to manufacturing industry of Guangxi in China to concretely abstract the credit risk and enterprise innovation into a measurable quantitative index, and compare the changes in credit risk before and after COVID-19. This paper selects 17 Listed Companies in Guangxi manufacturing industry as empirical samples, and calculates the expected default rate of different companies by using the traditional and modified KMV models. The larger the index value is, the higher the credit risk is, And then affect the enterprise innovation activities. The results show that the overall credit risk management ability of Guangxi’s manufacturing industry is relatively high, but by the impact of COVID-19, credit risk has increased. If left unguarded, it will have an impact on enterprise innovation.

A recursive algorithm for student selection of schools in a constrained serial dictatorship mechanism

ABSTRACT The constrained serial dictatorship mechanism is a popular method used in school admissions. However, due to the number of combinations possible, simulating the behaviour of students in their selection of schools and computing the best strategy for them to select a limited number of schools is currently a highly complex and time-consuming endeavour. The purpose of this study is to propose a recursive algorithm to significantly reduce this computational time and to provide an empirical application by employing this algorithm. To do this, I studied how the behaviours and utilities of students will change if provided with more choices for college admissions in Guangxi in China. The results indicate that neither the behaviours nor the utilities change significantly with the provision of more choices, which implies that increasing the available choices of schools for students in Guangxi would be a waste of resources.

Peer Education Intervention on Adolescents' Anxiety, Depression, and Sleep Disorder during the COVID-19 Pandemic.

Adolescents' anxiety and depression during the coronavirus disease 2019 (COVID-19) pandemic outbreak cannot be ignored. In public health crisis events, adolescents are prone to negative psychological problems, such as anxiety and depression. Hence, this research focuses on the use of reasonable and efficient methods to intervene in adolescents' psychological problems during the COVID-19 pandemic. From February to April 2020, we conducted an anonymous online survey on a total of 1,200 adolescents in the provinces of Hunan and Guangxi in China. Moreover, we randomly divided a total of 150 middle school students with anxiety scores greater than 50 and volunteered to participate in the intervention experiment into control and intervention groups, with 75 members in each group. On the basis of the proposed routine treatment, we conducted 8 weeks of model 328-based peer education intervention in the intervention group. After the intervention, the self-rating anxiety scale scores (SAS) of the intervention group are better than those of the control group (P<0.001). Moreover, the self-rating depression scale (SDS) scores of both groups are reduced, but the effect is more significant on the intervention group (P<0.001) than on the control group. Finally, the total Pittsburgh sleep quality index (PSQI) scores of both groups are reduced, but the effect is more significant on the intervention group than on the control group (P=0.001 and <0.001, respectively). Model 328-based peer education intervention can significantly reduce the level of anxiety and depression in adolescents and improve their sleep quality.

Microplastics in freshwater and wild fishes from Lijiang River in Guangxi, Southwest China

Microplastics (MPs) are ubiquitous contaminants of emerging concern that have gained great attention recently due to their widespread appearance in the environment and potential adverse effects on living biota. Lijiang in Guangxi in China is a world-famous place of tourist attraction and attracted thousands of visitors every year. However, little is known regarding occurrence and distribution of MPs in freshwater and wild fishes in the Lijiang River. In this study, we used stereoscopy and micro Fourier transform infrared spectrometry (μ-FTIR) methods to investigate the abundance, morphotype, size distribution, and polymer type of MPs in freshwater collected by plankton nets and bulk sampling by pumping and filtration. Results showed that abundance of MPs in freshwater with bulk sampling by pumping (67.5 ± 65.6 items/m3) was significantly higher than those using plankton nets (0.67 ± 0.41 items/m3 and 0.15 ± 0.15 items/m3 for mesh sizes of 75 μm and 300 μm, respectively). An average abundance of MPs detected in wild fishes was 0.6 ± 0.6 items/individual, of which, a majority was found in the gastrointestinal tracts. Large-sized (>0.3 mm) and colored MPs in morphotypes of flakes and fibers dominated in both freshwater and wild fishes. Polypropylene-polyethylene copolymer and polyethylene were the top two abundant polymer types of MPs in freshwater, while polyethylene terephthalate dominated in wild fishes. This study provides evidences for our better understanding of pollution status of MPs in the Lijiang River.

Unveiling the morphology of the Oriental rare monotypic ant genus Opamyrma YAMANE, BUI & EGUCHI, 2008 (Hymenoptera: Formicidae: Leptanillinae) and its evolutionary implications, with first descriptions of the male, larva, tentorium, and sting apparatus

The monotypic genus Opamyrma Yamane, Bui & Eguchi, 2008 (Hymenoptera, Formicidae, Leptanillinae) is an extremely rare relictual lineage of apparently subterranean ants, so far known only from a few specimens of the worker and queen from Ha Tinh in Vietnam and Hainan in China. The phylogenetic position of the genus had been uncertain until recent molecular phylogenetic studies strongly supported the genus to be the most basal lineage in the cryptic subterranean subfamily Leptanillinae. In the present study, we examine the morphology of the worker, queen, male, and larva of the only species in the genus, Opamyrma hungvuong Yamane, Bui & Eguchi, 2008, based on colonies newly collected from Guangxi in China and Son La in Vietnam, and provide descriptions and illustrations of the male, larva, and some body parts of the worker and queen (including mouthparts, tentorium, and sting apparatus) for the first time. The novel morphological data, particularly from the male, larva, and sting apparatus, support the current phylogenetic position of the genus as the most basal leptanilline lineage. Moreover, we suggest that the loss of lancet valves in the fully functional sting apparatus with accompanying shift of the venom ejecting mechanism may be a non-homoplastic synapomorphy for the Leptanillinae within the Formicidae.Open access, licensed under CC BY 4.0. © 2020 The Author(s).DOI: 10.25849/myrmecol.news_030:027Pages: 27-52Volume: 30Year: 2020Journal: Myrmecol. News

Genetic Diversity of Indigenous Pigs from South China Area Revealed by SNP Array.

Simple SummaryThe pig is one of the most important livestock animals, providing the majority of protein for humans. The population genetics analysis of pigs not only helps humans understand the domestication of the pig but also helps breeders in the genetic improvement of pigs. In this study, the population genetics of 11 pig breeds of South China were analyzed with the help of single nucleotide polymorphism (SNP) chips. The results showed that the genetic diversity of South China indigenous pigs is declining rapidly, and gene introgression from commercial pigs to indigenous pigs was detected. Selection signature analysis showed differences among South China indigenous pig breeds, commercial pig breeds, and wild pig breeds were present for meat quality and growth. Our study deepened understanding of the conservation status and selection mechanisms of Chinese indigenous pigs.To investigate the genetic diversity, population structure, extent of linkage disequilibrium (LD), effective population size (Ne), and selection signatures in indigenous pigs from Guangdong and Guangxi in China, 226 pigs belonging to ten diverse populations were genotyped using single nucleotide polymorphism (SNP) chips. The genetic divergence between Chinese and Western pigs was determined based on the SNP chip data. Low genetic diversity of Dahuabai (DHB), Luchuan (LC), Lantang (LT), and Meihua (MH) pigs, and introgression of Western pigs into Longlin (LL), MH, and Yuedonghei (YDH) pigs were detected. Analysis of the extent of LD showed that indigenous pigs had low LD when pairwise SNP distance was short and high LD when pairwise SNP distance was long. Effective population size analysis showed a rapid decrease for Chinese indigenous pigs, and some pig populations had a relatively small Ne. This result indicated the loss of genetic diversity in indigenous pigs, and introgression from Western commercial pigs. Selection signatures detected in this study overlapped with meat quality traits, such as drip loss, intramuscular fat content, meat color b*, and average backfat thickness. Our study deepened understanding of the conservation status and domestication of Chinese indigenous pigs.