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Abstract Background This cross-sectional study investigates infection prevention and control (IPC) competencies among healthcare professionals in northwest China, examining the influence of demographic factors, job titles, education, work experience, and hospital levels. Methods Data from 874 respondents across 47 hospitals were collected through surveys assessing 16 major IPC domains. Statistical analyses, including Mann-Whitney tests, were employed to compare competencies across variables. Results Significant differences were identified based on gender, job titles, education, work experience, and hospital levels. Females demonstrated higher IPC competencies, while senior positions exhibited superior performance. Higher educational attainment and prolonged work experience positively correlated with enhanced competencies. Variances across hospital levels underscored context-specific competencies. Conclusion Demographic factors and professional variables significantly shape IPC competencies. Tailored training, considering gender differences and job roles, is crucial. Higher education and prolonged work experience positively impact proficiency. Context-specific interventions are essential for diverse hospital settings, informing strategies to enhance IPC skills and mitigate healthcare-associated infections effectively.

Eclipta prostrata L. has been used in traditional medicine and known for its liver-protective properties for centuries. Wedelolactone (WEL) and demethylwedelolactone (DWEL) are the major coumarins found in E. prostrata L. However, the comprehensive characterization of these two compounds on non-alcoholic fatty liver disease (NAFLD) still remains to be explored. Utilizing a well-established zebrafish model of thioacetamide (TAA)-induced liver injury, the present study sought to investigate the impacts and mechanisms of WEL and DWEL on NAFLD through integrative spatial metabolomics with liver-specific transcriptomics analysis. Our results showed that WEL and DWEL significantly improved liver function and reduced the accumulation of fat in the liver. The biodistributions and metabolism of these two compounds in whole-body zebrafish were successfully mapped, and the discriminatory endogenous metabolites reversely regulated by WEL and DWEL treatments were also characterized. Based on spatial metabolomics and transcriptomics, we identified that steroid biosynthesis and fatty acid metabolism are mainly involved in the hepatoprotective effects of WEL instead of DWEL. Our study unveils the distinct mechanism of WEL and DWEL in ameliorating NAFLD, and presents a “multi-omics” platform of spatial metabolomics and liver-specific transcriptomics to develop highly effective compounds for further improved therapy.

Abstract Nitrogen (N) is an important nutrient for crop growth. However, the overuse of N fertilizers has led to a series of devastating global environmental issues. Recent studies show that multiple datasets have been created for agricultural N fertilizer application with varied temporal or spatial resolutions, nevertheless, how to synchronize and use these datasets becomes problematic due to the inconsistent temporal coverages, spatial resolutions, and crop-specific allocations. Here we reconstructed a comprehensive dataset for crop-specific N fertilization at 5-arc-min resolution (~10 km by 10 km) during 1961–2020, including N application rate, types, and placements. The N fertilization data was segmented by 21 crop groups, 13 fertilizer types, and 2 fertilization placements. Comparison analysis showed that our dataset is aligned with previous estimates. Our spatiotemporal N fertilization dataset could be used for the land surface models to quantify the effects of agricultural N fertilization practices on food security, climate change, and environmental sustainability.

Abstract Background Recurrent and metastatic thyroid cancer is more invasive and can transform to dedifferentiated thyroid cancer, thus leading to a severe decline in the 10-year survival. The thyroid-stimulating hormone receptor (TSHR) plays an important role in differentiation process. We aim to find a therapeutic target in redifferentiation strategies for thyroid cancer. Methods Our study integrated the differentially expressed genes acquired from the Gene Expression Omnibus database by comparing TSHR expression levels in the Cancer Genome Atlas database. We conducted functional enrichment analysis and verified the expression of these genes by RT-PCR in 68 pairs of thyroid tumor and paratumor tissues. Artificial intelligence-enabled virtual screening was combined with the VirtualFlow platform for deep docking. Results We identified five genes (KCNJ16, SLC26A4, TG, TPO, and SYT1) as potential cancer treatment targets. TSHR and KCNJ16 were downregulated in the thyroid tumor tissues, compared with paired normal tissues. In addition, KCNJ16 was lower in the vascular/capsular invasion group. Enrichment analyses revealed that KCNJ16 may play a significant role in cell growth and differentiation. The inward rectifier potassium channel 5.1 (Kir5.1, encoded by KCNJ16) emerged as an interesting target in thyroid cancer. Artificial intelligence-facilitated molecular docking identified Z2087256678_2, Z2211139111_1, Z2211139111_2, and PV-000592319198_1 (-7.3 kcal/mol) as the most potent commercially available molecular targeting Kir5.1. Conclusion This study may provide greater insights into the differentiation features associated with TSHR expression in thyroid cancer, and Kir5.1 may be a potential therapeutic target in the redifferentiation strategies for recurrent and metastatic thyroid cancer.

“Candidatus Liberibacter asiaticus” (CLas) is a notorious agent that causes Citrus Huanglongbing (HLB), which is transmitted by Diaphorina citri (D. citri). We recently found that the acquisition and transmission of CLas by D. citri was facilitated by Citrus tristeza virus (CTV), a widely distributed virus in the field. In this study, we further studied whether different CTV strains manipulate the host preference of D. citri, and whether endosymbionts variation is related to CTV strains in D. citri. The results showed that the non-viruliferous D. citri preferred to select the shoots infected with CTV, without strain differences was observed in the selection. However, the viruliferous D. citri prefered to select the mixed strain that is similar to the field’s. Furthermore, D. citri effectively acquired the CTV within 2–12 h depending on the strains of the virus. The persistence period of CTV in D. citri was longer than 24 days, without reduction of the CTV titers being observed. These results provide a foundation for understanding the transmission mode of D. citri on CTV. During the process of CTV acquisition and persistence, the titers of main endosymbionts in D. citri showed similar variation trend, but their relative titers were different at different time points. The titers of the “Candidatus Profftella armatura” and CTV tended to be positively correlated, and the titers of Wolbachia and “Candidatus Carsonella ruddii” were mostly negatively related with titers of CT31. These results showed the relationship among D. citri, endosymbionts, and CTV and provided useful information for further research on the interactions between D. citri and CLas, which may benefit the development of approaches for the prevention of CLas transmission and control of citrus HLB.

Grafting is a commonly used method for citrus propagation and transmitting 'Candidatus Liberibacter asiaticus' (CLas), the putative causing agent of citrus Huanglongbing (HLB). Optimization of the grafting inoculation methods facilitates the material preparation in HLB research. Citrus buds with CLas were grafted onto healthy sour tangerine (Citrus sunki Hort. ex Tanaka) seedlings by different methods such as top grafting ('T' grafting and 'V' grafting) and side grafting (abdominal grafting). Along with the symptom observation, titers of CLas in the leaves were detected by RT-qPCR monthly. The correlation between the growth status of buds or different grafting methods and the success rate of HLB transmission were analyzed. Our results suggest that sufficient DNA could be extracted to accurately detect the CLas from even only 0.0125 g leaf midrib or branch bark. The probability of CLas transmission was higher in plants inoculated with buds in better growth conditions. The success rate of 'T' grafting was significantly higher than that of side grafting and 'V' grafting. Additionally, in terms of HLB transmission efficiency, the two-bud grafting scheme was superior to the single-bud and three-bud grafting schemes. In conclusion, the grafting combinations with the highest HLB transmission efficiency were screened to provide a methodological reference for the practice or research of grafting to obtain plant material.

Diaphorina citri Kuwayama (D. citri) is an insect vector of phloem-limited ‘Candidatus Liberibacter asiatus’ (CLas), the presumed pathogen of citrus Huanglongbing (HLB). Recently, our lab has preliminarily found it acquired and transmitted Citrus tristeza virus (CTV), which was previously suggested to be vectored by species of aphids. However, the influences of one of the pathogens on the acquisition and transmission efficiency of the other pathogen remain unknown. In this study, CLas and CTV acquisition and transmission by D. citri at different development stages under field and laboratory conditions were determined. CTV could be detected from the nymphs, adults, and honeydew of D. citri but not from the eggs and exuviates of them. CLas in plants might inhibit CTV acquisition by D. citri as lower CTV–positive rates and CTV titers were detected in D. citri collected from HLB-affected trees compared to those from CLas–free trees. D. citri were more likely to obtain CTV than CLas from host plants co-infected with the two pathogens. Intriguingly, CTV in D. citri facilitated the acquisition and transmission of CLas, but CLas carried by D. citri had no significant effect on the transmission of CTV by the same vector. Molecular detection and microscopy methods confirmed the enrichment of CTV in the midgut after a 72-h acquisition access period. Collectively, these results raise essential scientific questions for further research on the molecular mechanism of pathogen transmission by D. citri and provide new ideas for the comprehensive prevention and control of HLB and CTV.

Huanglongbing (HLB) is the most harmful bacterial disease in citrus production in the world, and has been seriously ravaging the citrus groves of South China since the 1930s. The surveillance of the epidemiological characteristics of HLB is of utmost priority for citrus production in this region. In order to explore the effects of disease control measures, analyses on the space–time statistical features of the HLB epidemic, from 2019 to 2021, within six orchards in the Guangdong province are presented. Overall, the number of citrus plants in the orchards usually slightly decreased year by year. The reduction was mainly related to the level of plant susceptibility, which is correlated with citrus varieties. The maximum disease severity (incidence and race increment) was correlated with the awareness of this disease and the management intensity applied by the manager. A higher disease index was found in the conventional management orchards than in the comprehensive prevention and control orchards. Proper insect-protective screen houses can effectively prevent the epidemic of HLB, without affecting the fruit quality, and can also aid with higher yields. A high correlation was found between the geometry and topography of orchards and the HLB epidemic due to the wind direction from May to September and the Asia citrus psyllid activity characteristics. For flat orchards, the incidence of HLB in the north and entrance areas was higher than that in the southwest. In the mountain area, the incidence of the windward side in the south was higher than that of the leeward side in the north. Diseased trees tended to have an edge effect in the grove, whereas the trees of the same disease scale were found clustered in their distribution. These results allow a better understanding of HLB epidemiology and provide guidance for the early warning of HLB in new groves in areas that are severely affected by this disease. Furthermore, they also provide a scientific basis for the comprehensive prevention and control of HLB in old groves.

Dissolved organic carbon (DOC) plays an important role in the carbon cycle, radiative forcing, and biogeochemistry in cryospheric regions. In this study, concentrations, light-absorption properties and bioavailability of DOC from snow cover in Alaska were characterized. Results indicated that average concentrations of DOC in snow of Alaska (0.17 − 0.30 mg L−1) were lower than that found in Asian mountainous glaciers, but higher that found from polar regions snow. No significant trend of DOC was observed during April to May in 2017 due to the short term study; while the vertical variations generally showed a little higher values in the surface snow than that in the sub-surface snow. An obvious characteristic of DOC light-absorbance in snow between the wavelength of 300 and 700 nm indicated the mass absorption cross section of DOC at 365 nm (MACDOC365) was 0.32 ± 0.24 and 0.37 ± 0.32 m2 g−1 for the snow cover at Barrow site (Arctic Ocean coast) and the other Alaskan regions, respectively. The MACDOC365 values increased especially during snow melting, indicating the DOC with high MAC values were prone to retain in snow. The proportion of radiative forcing caused by DOC relative to that by black carbon in snow was approximately 2.3%, indicating that DOC in snow should be considered during the accelerated melt of snow cover. The bioavailability experiment of DOC in snow indicated that DOC may be an important bioavailable source for proglacial and coastal ecosystems in Alaskan Arctic regions. Using backward air mass trajectory analysis, we suggested that DOC deposited in snow at Barrow primarily originates from marine or terrestrial air mass, but the specific contribution of different sources cannot be quantified without data related to the DOC’s chemical composition and carbon isotopic signatures. This study highlighted the climatic implications of DOC in snow in the Arctic regions.

“Candidatus Liberibacter asiaticus” (CLas) is a phloem-restricted α-proteobacterium that is associated with citrus huanglongbing (HLB), which is the most destructive disease that affects all varieties of citrus. Although midrib is usually used as a material for CLas detection, we recently found that the bacterium was enriched in fruits, especially in the fruit pith. However, no study has revealed the molecular basis of these two parts in responding to CLas infection. Therefore, we performed transcriptome and UHPLC–MS-based targeted and untargeted metabolomics analyses in order to organize the essential genes and metabolites that are involved. Transcriptome and metabolome characterized 4834 differentially expressed genes (DEGs) and 383 differentially accumulated metabolites (DAMs) between the two materials, wherein 179 DEGs and 44 DAMs were affected by HLB in both of the tissues, involving the pathways of phenylpropanoid biosynthesis, phytohormone signaling transduction, starch and sucrose metabolism, and photosynthesis. Notably, we discovered that the gene expression that is related to beta-glucosidase and endoglucanase was up-regulated in fruits. In addition, defense-related gene expression and metabolite accumulation were significantly down-regulated in infected fruits. Taken together, the decreased amount of jasmonic acid, coupled with the reduced accumulation of phenylpropanoid and the increased proliferation of indole-3-acetic acid, salicylic acid, and abscisic acid, compared to leaf midribs, may contribute largely to the enrichment of CLas in fruit piths, resulting in disorders of photosynthesis and starch and sucrose metabolism.

Global changes in precipitation and atmospheric N deposition affect the geochemical cycle of the element and its hydrological cycle in the ecosystem. It may also affect the relationship between plant water use efficiency (WUE) and nutrients, as well as the relationship between plant nutrients. Desert ecosystems are vulnerable to global changes. Haloxylon ammodendron is the dominant species in the Asian desert. Revealing the variations in these relationships in H. ammodendron with precipitation and N deposition will enhance our understanding of the responses of plants to global change in terms of trade-off strategies of nutrient absorption, water and element geochemical cycles in desert ecosystems. Thus, we conducted field experiments with different amounts of water and N. This study showed that WUE of H. ammodendron was not correlated with nitrogen content (N), phosphorus content (P), and potassium content (K) when water and N supply were varied (p > 0.05 for WUE vs. N, P, and K), suggesting lack of coupling between water use and nutrient economics. This result was associated with the lack of correlation between plant nutrients and gas exchang in H. ammodendron. However, water addition, N addition and the interaction between both of them all played a role in the correlation between plant N, P and K owing to their different responses to water and N supplies. This indicates that global changes in precipitation and N deposition will affect N, P and K geochemical cycles in the Asian deserts dominated by H. ammodendron, and drive changes in the relationships between plant nutrients, resulting in changes in the trade-off strategy of plant absorption of N, P, and K.

ObjectiveHuman astroviruses (HAstVs) are single-stranded RNA viruses of the Astroviridae family. Infection of classic HAstVs is one of the most common causes of acute viral gastroenteritis (infectious viral diarrhea). There is a lack of data on the prevalence and genetic characterization of classic HAstVs in acute viral gastroenteritis in the whole population. This study aimed to investigate the epidemiological trend, genotypes, viral co-infections, and viral loads of classic HAstVs in Shanghai, China, from January 2015 to December 2016.MethodsA total of 6,051 non-redundant stool samples were collected in outpatients with acute diarrhea in Shanghai from January 2015 to December 2016. One-step real-time RT-PCR was used for screening viral diarrhea, including rotavirus A, rotavirus B, rotavirus C, norovirus genotype I and II, classic human astroviruses, and sapovirus. Real-time PCR was used for screening human enteric adenoviruses. Conventional RT-PCR was used for the amplification of viral fragments for genotyping. PCR products were sequenced and used for the construction of phylogenetic trees.ResultsThe detection rate of classic HAstVs was 1.55% (94/6,051). The prevalence of HAstV infection displayed a typical winter/spring (December to March) seasonality and was highest in the 5–14 age group. Eighty-six samples were genotyped, which revealed HAstV-1 as the most prevalent genotype, followed by HAstV-5, HAstV-4, HAstV- 2, HAstV-8, and HAstV-3. There was a dramatic rise in the prevalence of HAstV-4 from December 2015 to March 2016, and the viral loads of HAstV-4 were significantly higher than those of other genotypes. Among the mixed infection samples, noroviruses were found to be the most frequently co-infected enteric viruses with HAstV.ConclusionMultiple genotypes of classic HAstVs circulated in Shanghai from January 2015 to December 2016. For the first time, HAstV-3\4\5\8 were detected in Shanghai.

The operational environment faced by modern radars is becoming increasingly complex. The timely detection of the failure of a node and the adoption of countermeasures to ensure the stable operation of the system have become the focus of radar network management. In this study, based on traditional heartbeat detection algorithm, we use a radial-basis neural network model to predict the timeout value. Therefore, a neural network heartbeat detection algorithm is proposed, which is used to detect the failure of the combat platform. The experimental results show that the proposed algorithm can be used to reduce the failure detection delay and misjudge rate as compared with the existing algorithms, and can be applied to a complex radar network environment.

Nitrogen (N) partitioning between plant and soil pools is closely related to biomass accumulation and allocation, and is of great importance for quantifying the biomass dynamics and N fluxes of ecosystems, especially in low N-availability desert ecosystems. However, partitioning can differ among species even when growing in the same habitat. To better understand the variation of plant biomass allocation and N retention within ephemeral and annual species we studied the responses of MalcolmiaAfricana (an ephemeral) and Salsola affinis (an annual) to N addition, including plant growth, N retention by the plant and soil, and N lost to the environment using 15N (double-labeled 15NH415NO3 (5.16% abundance) added at 0, 0.8, 1.6, 3.2, and 6.4 g pot-1, equivalent to 0, 15, 30, 60, and 120 kg N ha-1) in a pot experiment. Higher N addition (N120) inhibited plant growth and biomass accumulation of the ephemeral but not the annual. In addition, the aboveground:belowground partitioning of N (the R:S ratio) of the ephemeral decreased with increasing N addition, but that of the annual increased. The N input corresponding to maximum biomass and 15N retention of the ephemeral was significantly less than that of the annual. The aboveground and belowground retention of N in the ephemeral were significantly less than those of the annual, except at low N rates. The average plant–soil system recovery of added 15N by the ephemeral was 70%, significantly higher than that of the annual with an average of 50%. Although the whole plant–soil 15N recovery of this desert ecosystem decreased with increasing N deposition, our results suggested that it may vary with species composition and community change under future climate and elevated N deposition.

ABSTRACT Soil salinization is a growing environmental problem caused by both natural and human activities. Excessive salinity in soil suppresses growth, decreases species diversity, and alters the community composition of plants; however, the effect of salinity on soil microbial communities is poorly understood. Here, we characterize the soil microbial community along a natural salinity gradient in Gurbantunggut Desert, Northwestern China. Microbial diversity linearly decreased with increases in salinity, and community dissimilarity significantly increased with salinity differences. Soil salinity showed a strong effect on microbial community dissimilarity, even after controlling for the effects of spatial distance and other environmental variables. Microbial phylotypes (n = 270) belonging to Halobacteria, Nitriliruptoria, [Rhodothermi], Gammaproteobacteria, and Alphaproteobacteria showed a high-salinity niche preference. Out of nine potential phenotypes predicted by BugBase, oxygen-related phenotypes showed a significant relationship with salinity content. To explore the community assembly processes, we used null models of within-community (nearest-taxon index [NTI]) and between-community (βNTI) phylogenetic composition. NTI showed a significantly negative relationship with salinity, suggesting that the microbial community was less phylogenetically clustered in more-saline soils. βNTI, the between-community analogue of NTI, showed that deterministic processes have overtaken stochastic processes across all sites, suggesting the importance of environmental filtering in microbial community assembly. Taken together, these results suggest the importance of salinity in soil microbial community composition and assembly processes in a desert ecosystem. IMPORTANCE Belowground microorganisms are indispensable components for nutrient cycling in desert ecosystems, and understanding how they respond to increased salinity is essential for managing and ameliorating salinization. Our sequence-based data revealed that microbial diversity decreased with increasing salinity, and certain salt-tolerant phylotypes and phenotypes showed a positive relationship with salinity. Using a null modeling approach to estimate microbial community assembly processes along a salinity gradient, we found that salinity imposed a strong selection pressure on the microbial community, which resulted in a dominance of deterministic processes. Studying microbial diversity and community assembly processes along salinity gradients is essential in understanding the fundamental ecological processes in desert ecosystems affected by salinization.

Wind-blown dust derived from the arid and semi-arid regions is an important atmospheric component affecting the Earth's radiation budget. Dust storms are prevailing in central Asia. Deposition of atmospheric dust in snow was measured on Glacier No.12 (5040 m a.s.l.) in the Laohugou Basin and Shiyi Glacier (4510 m a.s.l.) in the Yeniugou Basin, of western Qilian Mountains, China, mainly focusing on dust concentration and size distribution, chemistry, SEM–EDX analysis and Nd–Sr isotopic composition. An analysis of spatial distribution of dust concentration and size distribution in the snow cover at two sites suggests that deposition of dust in western Qilian Mountains is different between sites as the environment changes from west to east. Mean mass concentration of dust with 0.57 < d

Background: Chimeric antigen receptor T cells (CAR-Ts) have demonstrated remarkable efficacy in hematological cancers but have not yet translated in treating solid tumors. The significant hurdles limiting CAR-T therapy were from a paucity of differentially expressed cell surface molecules on solid tumors that can be safely targeted. Here, we present TSH receptor (TSHR) as a putative target for CAR-T therapy of differentiated thyroid cancer (DTC). Methods: We undertook a large-scale screen on thyroid cancer tissues and multiple internal organs through bioinformatical analysis and immunohistochemistry to date TSHR expression. Using 3 previously described monoclonal antibodies, we generated 3 third-generation CAR-Ts. We tested anti-TSHR CAR-T in vitro activity by T-cell function and killing assay. Then we tested preclinical therapeutical efficacy in a xenograft mouse model of DTC and analyzed mice’s physical conditions and histological abnormalities to evaluate anti-TSHR CAR-T’s safety. Results: TSHR is highly and homogeneously expressed on 90.8% (138/152) of papillary thyroid cancer, 89.2% (33/37) of follicular thyroid cancer, 78.2% (18/23) of cervical lymph node metastases, and 86.7% of radioactive iodine resistance diseases. We developed 3 novel anti-TSHR CAR-Ts from monoclonal antibodies M22, K1-18, and K1-70; all 3 CAR-Ts mediate significant antitumor activity in vitro. Among these, we demonstrate that K1-70 CAR-T can have therapeutical efficacy in vivo, and no apparent toxicity has been observed. Conclusion: TSHR is a latent target antigen of CAR-T therapy for DTC. Anti-TSHR CAR-T could represent a therapeutic option for patients with locoregional relapsed or distant metastases of thyroid cancer and should be tested in carefully designed clinical trials. [ABSTRACT FROM AUTHOR]

Variations in precipitation and atmospheric N deposition affect water and N availability in desert, and thus may have significant effects on desert ecosystems. Haloxylon ammodendron is a dominant plant in Asian desert, and addressing its physiological acclimatization to the changes in precipitation and N deposition can provide an insight into how desert plants adapt extreme environment by physiological adjustment. Carbon isotope ratio (δ13C) in plants has been suggested as a sensitive long-term indicator of physiological acclimatization. Therefore, this study evaluated the effect of precipitation change and increasing atmospheric N depositon on δ13C of H. ammodendron. Furthermore, Haloxylon ammodendron is a C4 plant, whether its δ13C can indicate water use-efficiency (WUE) has not been addressed. In the present study, we designed a field experiment with a completely randomized factorial combination of N and water, and measured δ13C, gas exchange and WUE of the assimilating branches of H. ammodendron. δ13C in H. ammodendron remained stable under N and water supply, while N addition, water addition and their interaction affected gas exchange and WUE in H. ammodendron. In addition, δ13C had no correlation with WUE. This result are associated with the irrelevance between δ13C and c[sub i]/c[sub a], which might be caused by a special value (0.37) of the degree of bundle-sheath leakiness (φ) or a lower activity of carbonic anhydrase (CA) of H. ammodendron. Thus, δ13C of H. ammodendron cannot be used for indicating its WUE. [ABSTRACT FROM AUTHOR]

Soil respiration (Rs) is the most important source of carbon dioxide emissions from soil to atmosphere. However, it is unclear what the interactive response of Rs would be to environmental changes such as elevated precipitation, nitrogen (N) deposition and warming, especially in unique temperate desert ecosystems. To investigate this an in situ field experiment was conducted in the Gurbantunggut Desert, northwest China, from September 2014 to October 2016. The results showed that precipitation and N deposition significantly increased Rs, but warming decreased Rs, which was mainly through its impact on the variation of soil moisture at 5 cm depth. In addition, the interactive response of Rs to combinations of the factors was much less than that of any single-factor, and the main interaction being a positive effect, except interaction from increased precipitation and high N deposition (60 kg N ha-1 yr-1). Although Rs was found to be a unimodal change pattern with the variation of soil mositure, soil temperature and soil NH4+-N content, and it was signicantly postively correlated to soil dissloved organic carbon (DOC) and pH, but from a structural equation model found that soil temperature was the most important controlling factor. Those results indicated that Rs was mainly interactively controlled by the soil multi-environmental factors and soil nutrients, and was very sensitive to elevated precipitation, N deposition and warming. But the interactions of multiple factors largely reduced between-year variation of Rs more than any single-factor, suggesting that the carbon cycle in temperate deserts could be profoundly influenced by positive carbon-climate feedbacks. [ABSTRACT FROM AUTHOR]

Macrophorins are representative examples of isoprenoid epoxycyclohexenones containing cyclized drimane moieties. We located and characterized the biosynthetic gene cluster of macrophorin from Penicillium terrestris. MacJ encoded by this cluster was characterized to be the first example of a membrane-bound type-II terpene cyclase catalyzing the cyclization of meroterpenoids via direct protonation of the terminal olefinic bond in acyclic yanuthones. The late-stage functionalization and substrate promiscuity of MacJ make it a potential biocatalyst for the synthesis of macrophorin analogues. [ABSTRACT FROM AUTHOR]

Selective and sensitive determination of nitrite is of great importance in practical application. In the present work, a novel nitrite sensing platform was built based on the fabrication of nitrogen-doped-carbon-coated hexagonal cobalt oxyhydroxide (CN@CoOOH) on reduced graphene oxide (RGO) using zeolitic imidazolate framework (ZIF)-67 as a precursor. The CN@CoOOH/RGO nanocomposite was confirmed by UV–visible spectroscopy, Fourier transform infrared spectroscopy, x-ray photoelectron spectrum, transmission electron microscopy, scanning electron microscopy, and x-ray diffraction. We applied the nanocomposite to detect nitrite selectively and sensitively through amperometry for the first time. The anodic current values increased with the addition of nitrite. Therefore, the concentrations of nitrite were quantitatively detected using a CN@CoOOH/RGO based sensor. A wider linear range of 0.1 to 7000 μM was obtained with a lower detection limit of 10 nM (S/N = 3). The proposed method was also applied to detect nitrite released from normal liver cells and human hepatoma cells. [ABSTRACT FROM AUTHOR]

When tunnel blasting is commenced through the subway station, it will cause the vibration of the station structure. The purpose of this paper is to explore the maximum allowable vibration velocity of the normal operation of the subway during the implementation process of tunneling projects, and to ensure the normal and safe operation of the subway during the construction. An example is given regarding the down-traversing of the power tunnel to the Convention and Exhibition Center Station in the Yanta four circuit transmission line transformation project of Dalian, in which the stations are set along the track bed and bottom of the side walls of the rail line. The vibration response and corresponding main vibration frequency at each station were monitored. It was found that the response value of the vibration velocity of the track bed was distributed 0.5 to 2.0 cm/s; the average response value of the vibration velocity on one side wall for the previous construction on the rail line is 0.3 cm/s, and the distribution range of the main vibration frequency is 50 to 140 Hz; the response of the vibration velocity on the other side wall for the subsequent construction on the rail line is large with a mean value of 0.6 cm/s, and the distribution range of the main vibration frequency is 40 to 180 Hz. Based on these research results and the relevant specifications, the authors state that the monitoring work on the normal operation of the subway should be based on the monitoring work of the track bed and should allow the maximum vibration velocity of the particles to be 1.1 cm/s and 0.8 cm/s, and the corresponding main vibration frequency ranges of 70 to 100 Hz and 35 to 60 Hz, respectively. The present paper’s research results are of use as guidance for further studies and they put forth the maximum allowable particle velocity of subway operation during tunnel blasting construction of a down-traversing subway station. [ABSTRACT FROM AUTHOR]

This work discusses the temporal variation of various physicochemical species in the meltwater runoff of Laohugou Glacier No. 12 (4260 m a.s.l.) in central Asia, and their correlation with dust particles, based on a two-year field observation in summer 2012 and 2013, mainly focusing on dust concentration and size distribution, meltwater chemistry, particles SEM-EDX analysis in the meltwater, and MODIS atmospheric optical depth fields around the Qilian Mountains in central Asia. We find that, the volume-size distribution of dust particles in the meltwater is mainly composed of three parts, which includes fine aerosol particles (with diameter of 0 ~3.0 µm, mainly PM 2.5), atmospheric dust (with diameter of 3.0 ~20 µm), and local dust particles (20 ~100 µm), respectively. Comparison of dust particles in the snowpack and meltwater runoff indicates that, large part of dust particles in the meltwater may have originated from atmospheric dust deposition to the snow and ice on the glacier, and transported into the meltwater runoff. Moreover, temporal variation of dust and major ions (especially crustal species) is very similar with each other, showing great influence of dust particles to the chemical constituents of the glacier meltwater. SPM and TDS implied significant influences of dust to the physical characteristics of the glacier meltwater. Results showed that, accelerated glacier melting may affect physicochemical characteristics of the meltwater at an alpine basin under global warming. MODIS atmospheric optical depth (AOD) fields derived using the Deep Blue algorithm, showed great influence of regional dust transportation over western Qilian Mountains in springtime. SEM-EDX analysis shows that dust particles in the glacier meltwater contain Si-, Al-, Ca-, K-, and Fe-rich materials, such as quartz, albite, aluminate, and fly ash, similar to that deposited in snowpack. These results showed great and even currently underestimated influences of atmospheric dust deposition to glacier meltwater physicochemistry at an alpine basin in central Asia. [ABSTRACT FROM AUTHOR]