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The beetle Ophraella communa is an effective biological control agent against the invasive common ragweed spread across various ecosystems with variable temperature ranges. The trend in climate change attributed to fluctuating temperatures and abrupt rainfalls is expected to continue. This study aimed to better understand the effects of thermal fluctuation on O. communa by exposing all their life stages to heat stress under different treatments. Repeated exposure to high temperatures, relative to constant milder temperatures, increased the duration of immature development, mean generation time, and the adult longevity, decreased the intrinsic rate of increase, finite rate of population increase, net reproductive rate, survival rate, overall longevity, body length, and mass of adults and positively affected overall fecundity by prolonging the oviposition period, biasing sex ratio towards females. After exposure to heat stress, the mating success and production of viable offspring were higher in O. communa. Our findings demonstrate that exposure to heat stress negatively affects ragweed beetles, but they were able to survive and reproduce.

Various land degradation processes have led to land productivity reduction, food insecurity and ecosystem destruction. The Loess Plateau (LP) suffered from severe land degradation, such as vegetation degradation, soil erosion and desertification. This study assessed land degradation changes by considering different land degradation types including vegetation degradation, soil erosion, aridity, loss of soil organic carbon and desertification in the Huangfuchuan watershed of the northern LP. A comprehensive land degradation index (LDI) was developed by combining different degradation processes using the fuzzy logic modeling method. Our results showed significant land use transitions from bare land and sandy area to grass land and forest land from 1990 to 2018, which were consistent with an obvious increase in vegetation cover from 31.24% to 40.72%. The soil erosion rate predicted by the RUSLE model decreased by 51.95% during 1990–2018. The basin-average LDI decreased from 0.68 in 1990 to 0.51 in 2018, suggesting the great success of land degradation prevention in a fragile ecological environment region on the LP during the past decades. This study proposed an integrated framework for land degradation assessment in the high erodible area. The results can provide good references for the improvement of ecological environment in the future.

Royal jelly (RJ) is a kind of bee product widely used in cosmetics, medicine and other fields. Not only can RJ regulate the physiological function of bee population, but also play a specific biological role in many diseases. This paper overviews the main active ingredients in the functional food RJ, including major royal jelly protein, fatty acids, phenols, flavonoids, etc, and summarizes the active role of RJ in the maintenance of human health, such as the regulation of immunity, lifespan, memory, digestive system, blood glucose, obesity, antibacterial and anti-cancer effect, among which the regulation of memory can be used in the treatment of Alzheimer's disease. These findings will benefit for comprehensive understanding and use of RJ, hence making it more effective in maintaining health.

Objectives This study quantified how the efficiency of testing and contact tracing impacts the spread of COVID-19. The average time interval between infection and quarantine, whether asymptomatic cases are tested or not, and initial delays to beginning a testing and tracing programme were investigated.Setting We developed a novel individual-level network model, called CoTECT (Testing Efficiency and Contact Tracing model for COVID-19), using key parameters from recent studies to quantify the impacts of testing and tracing efficiency. The model distinguishes infection from confirmation by integrating a ‘T’ compartment, which represents infections confirmed by testing and quarantine. The compartments of presymptomatic (E), asymptomatic (I), symptomatic (Is), and death with (F) or without (f) test confirmation were also included in the model. Three scenarios were evaluated in a closed population of 3000 individuals to mimic community-level dynamics. Real-world data from four Nordic countries were also analysed.Primary and secondary outcome measures Simulation result: total/peak daily infections and confirmed cases, total deaths (confirmed/unconfirmed by testing), fatalities and the case fatality rate. Real-world analysis: confirmed cases and deaths per million people.Results (1) Shortening the duration between Is and T from 12 to 4 days reduces infections by 85.2% and deaths by 88.8%. (2) Testing and tracing regardless of symptoms reduce infections by 35.7% and deaths by 46.2% compared with testing only symptomatic cases. (3) Reducing the delay to implementing a testing and tracing programme from 50 to 10 days reduces infections by 35.2% and deaths by 44.6%. These results were robust to sensitivity analysis. An analysis of real-world data showed that tests per case early in the pandemic are critical for reducing confirmed cases and the fatality rate.Conclusions Reducing testing delays will help to contain outbreaks. These results provide policymakers with quantitative evidence of efficiency as a critical value in developing testing and contact tracing strategies.

ObjectiveA low concentration of plasma triiodothyronine (T3) indicates euthyroid sick syndrome (ESS), which could be associated with a poor outcome in patients in intensive care units (ICUs). This study evaluated the relationship between ESS and prognostic indicators in patients admitted to an ICU and examined the free T3 (FT3) cut-off points that could be associated with 28-day mortality.MethodsThis prospective observational study included patients admitted to the ICU of The Third Hospital of Hebei Medical University between February and November 2018. Baseline variables and data on the occurrence of low FT3 were collected. The patients were divided into ESS (FT3 < 3.28 pmol/L) and non-ESS groups. The relationship between ESS and prognostic indicators in patients admitted to the ICU was evaluated, and the FT3 cut-off points that could be associated with 28-day mortality were examined.ResultsOut of a total of 305 patients, 118 (38.7%) were in the ESS group. Levels of FT3 (P < 0.001) and FT4 (P = 0.001) were lower, while the 28-day mortality rate (P < 0.001) and hospitalization expenses in the ICU (P = 0.001) were higher in the ESS group. A univariable analysis identified ESS, FT3, free thyroxine (FT4)/FT3, the APACHE II score, the sequential organ failure (SOFA) score, the duration of mechanical ventilation, creatinine (CREA) levels, the oxygenation index (HGB), white blood cells, albumin (ALB) levels, age, and brain natriuretic peptide (BNP) levels as factors associated with 28-day mortality (all P < 0.05). The cut-off value of FT3 for 28-day mortality was 2.88 pmol/L, and the 28-day mortality rate and hospitalization expenses in the ICU were higher in patients with ESS. The syndrome was confirmed to be independently associated with 28-day mortality.ConclusionThis study determined the incidence of ESS in the comprehensive ICU to be 38.7%. APACHE II, SOFA, BNP, APTT, HGB, PLT, CREA, ALB, FT4, SBP, and DBP are closely related to ESS, while BNP, PLT, and ALB are independent risk factors for the syndrome.

Despite the fact that copper (Cu) is a vital micronutrient to maintain body function, high doses of Cu through environmental exposure damage various organs, especially the liver, which is the main metabolic organ. To investigate the influence of long-term Cu-induced toxicity on mitophagy and apoptosis in rat liver, 96 seven-month-old male Sprague-Dawley rats were fed TBCC for 24 weeks. The results revealed that exposure to high Cu concentrations could promote oxidative stress liver injury by increasing the hepatic function index (ALT, AST and ALP) and MDA content, while reducing the activity of antioxidant enzymes (T-SOD, GSH-Px and CAT) related to oxidative stress. Consistent with histopathological observations, proper dietary Cu (15–60 mg/kg) could improve antioxidant stress levels and induce a dose-dependent increase in the mRNA expression of mitophagy-related genes, whereas a high Cu concentration (120 mg/kg) could cause severe liver impairment and ultrastructural changes and a reduction in mitophagosomes, accompanied by downregulation of Atg5, Beclin1, Pink1, Parkin, NIX, P62 and LC3B. The expression of apoptosis-related genes (Bax, Bax/Bcl-2, Caspase3, Cytc and p53) and proteins (Caspase3 and p53) was upregulated with the addition of dietary Cu. The results demonstrated that an appropriate dose of TBCC could improve liver function by promoting mitophagy and Cu enzymes that play antioxidative roles, while the accumulation of excess Cu could induce liver lesions by enhancing apoptosis and inhibiting mitophagy pathways.

Among different synthetic compounds copper (Cu) is persistently and frequently used as growth promoter, antibacterial, antifungal and antiparasitic agent and has become common environmental pollutant. Therefore, this study explores the cardio-toxic effects of control group (10 mg/kg bw Cu) and treatment group (125 and 250 mg/kg bw Cu), and it association with process of autophagy and metabolomics in myocardium of pigs kept in three different experimental treatments for a period of 80 days. The results of serum biochemical parameters showed a significantly increase in creatinine kinase (CK), creatine kinase-MB (CK-MB), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and aspartate aminotransferase (AST) in pigs exposed to 125 mg/kg bw and 250 mg/kg bw Cu. Meanwhile, the severe structural abnormalities in cardiomyocytes were found when exposed to 250 mg/kg Cu at day 80. In addition, the mRNA and proteins (Beclin1, ATG5 and LC3II) expression levels were significantly increased and p62 was significantly decreased in cardiomyocytes exposed to 250 mg/kg Cu at day 80 of the trial. Further, UPLC-QTOF/MS technique showed that 7 metabolites were up-regulated and 37 metabolites were down-regulated in cardiomyocytes after 250 mg/kg Cu treatment, with a principal impact on the metabolic pathways including glycerophospholipid metabolism, one carbon pool by folate, fatty acid elongation and fatty acid degradation, which were related to autophagy. Overall, our study identified the autophagy processes and metabolites in metabolic pathways in Cu-induced myocardium injury, which provided useful evidence of myocardium toxicity caused by Cu exposure via metabolomics and multiple bioanalytic methods.

Royal jelly (RJ) is a natural bee product that contains a variety of biologically active ingredients and has antitumor, antiallergic, antibacterial and immune-regulating effects. Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the intestine that can cause abdominal pain and diarrhea. With this study, we aimed to explore the protective effect of RJ on DSS-induced colitis in mice. The physiochemical parameters (water, protein, 10-hydroxy-2-decenoic acid, total sugar, starch, ash and acidity) of the RJ samples used in this study met the requirements of the international and Chinese national standards. Treatment with RJ improved symptoms and colonic cell apoptosis and decreased intestinal permeability by increasing the expression of tight-junction protein, goblet cells and their secretion mucin, MUC2, in DSS-induced ulcerative colitis mice. RJ also reduced the expression of proinflammatory cytokine IL-6 and increased the expression of anti-inflammatory cytokine IL-10 and sIgA. DSS resulted in an increase in the relative abundance of Parabacteroides, Erysipelotrichaceae, Proteobacteria (Gammaproteobacteria, Enterobacteriales and Enterobacteriaceae) and Escherichia Shigella in the colon and a decrease in the relative abundance of Muribaculum. In the RJ treatment group, the relative abundance of the above intestinal flora was improved by treatment with 2.0 g/kg RJ. These results suggested that RJ alleviated DSS-induced colitis by improving the colonic mucosal barrier.

Agasicles hygrophila is a classical biological agent used to control alligator weed (Alternanthera philoxeroides). Previous research has indicated that the heat shock factor (HSF) is involved in regulating the transcriptional expression of Hsp70 in response to heat resistance in A. hygrophila. However, the regulatory mechanism by which AhHsf regulates the expression of AhHsp70 remains largely unknown. Here, we identified and cloned a 944 bp AhHsp70 promoter (AhHsp70p) region from A. hygrophila. Subsequent bioinformatics analysis revealed that the AhHsp70p sequence contains multiple functional elements and has a common TATA box approximately 30 bp upstream of the transcription start site, with transcription commencing at a purine base approximately 137 bp upstream of ATG. Promoter deletion analyses revealed that the sequence from −944 to −744 bp was the core regulatory region. A dual-luciferase reporter assay indicated that overexpressed AhHsf significantly enhanced the activity of AhHsp70p. Furthermore, qPCR showed that AhHsp70 expression increased with time in Spodoptera frugiperda (Sf9) cells, and AhHsf overexpression significantly upregulated AhHsp70 expression in vitro. Characterization of the upstream regulatory mechanisms demonstrated that AhHsf binds to upstream cis-acting elements in the promoter region of AhHsp70 from −944 to −744 bp to activate the AhHSF–AhHSP pathway at the transcriptional level to protect A. hygrophila from high temperature damage. Furthermore, we proposed a molecular model of AhHsf modulation of AhHsp70 transcription following heat shock in A. hygrophila. The findings of this study suggest that enhancing the heat tolerance of A. hygrophila by modulating the upstream pathways of the Hsp family can improve the biocontrol of A. philoxeroides.

Heat shock proteins are molecular chaperones that are involved in numerous normal cellular processes and stress responses, and heat shock factors are transcriptional activators of heat shock proteins. Heat shock factors and heat shock proteins are coordinated in various biological processes. The regulatory function of heat shock factors in the expression of genes encoding heat shock proteins (Hsps) has been documented in some model insects, however, the role of transcription factors in modulating Hsps in other insects is still limited. In this study, one heat shock factor gene (AhHsf) was isolated and its two potential target genes (AhHsp70 and AhsHsp21) were confirmed from Agasicles hygrophila. AhHsf sequence analysis indicated that it belongs to the Hsfs gene family. RT-qPCR showed that expression levels of heat shock factors and of two heat shock proteins significantly increased under heat stress. Injection with double-stranded Hsf RNA in freshly emerged adult beetles significantly inhibited expression of AhHsp70 and AhsHsp21, shortened the adult survival, drastically reduced egg production, and ultimately led to a decrease in fecundity. RNA interference (RNAi)-mediated suppression of AhHsp70 or AhsHsp21 expression also significantly affected expression of AhHsf. Our findings revealed a potential transcriptional function of AhHsf to regulate expression of AhHsp70 and AhsHsp21, which may play a key role in A. hygrophila thermotolerance. Our results improve our understanding of the molecular mechanisms of the AhHsf - AhHsps signaling pathway in A. hygrophila.

Ophraella communa is an effective bio-control agent of the invasive common weed. By now, the reference genes in O. communa have not yet been screened and validated. The aim of this study was to screen for the most stable reference genes in different backgrounds, such as different developmental stages, sexes, tissues, and male reproductive system with different body sizes. We selected 12 common housekeeping genes involved in different biological processes, including GAPDH, ACT1, ACT2, ARF1, ARF4, SDH, βTUBC, RPL4, RPL19, RPS18, EF1α, and COX as the candidate reference genes. To analyze the stability of the candidate reference genes, we first used three dedicated algorithms, GeNorm, NormFinder, and BestKeeper, and further comprehensive ranking was provided by ReFinder. The results showed that RPL19 and RPL4 exhibited the least variation in different developmental stages/sexes and in male reproductive systems with different body sizes. COX proved to be most suitable for normalizing the gene expression levels in different tissues, and coincidentally, RPL19 was also found to be second in terms of stability in this study. To the best of our knowledge, this is the first study to identify suitable reference genes for analyzing gene expression in O. communa; thus, this study would lay the foundation for future research on the molecular physiology and biochemistry of O. communa and other insects.

ABSTRACT The intestinal microbiota is significantly affected by the external environment, but our understanding of the effects of extreme environments such as plateaus is far from adequate. In this study, we systematically analyzed the variation in the intestinal microbiota and 76 blood clinical indexes among 393 healthy adults with different plateau living durations (Han individuals with no plateau living, with plateau living for 4 to 6 days, with plateau living for >3 months, and who returned to the plain for 3 months, as well as plateau-living Tibetans). The results showed that the high-altitude environment rapidly (4 days) and continually (more than 3 months) shaped both the intestinal microbiota and clinical indexes of the Han population. With prolongation of plateau living, the general characteristics of the intestinal microbiota and clinical indexes of the Han population were increasingly similar to those of the Tibetan population. The intestinal microbiota of the Han population that returned to the plain area for 3 months still resembled that of the plateau-living Han population rather than that of the Han population on the plain. Moreover, clinical indexes such as blood glucose were significantly lower in the plateau groups than in the nonplateau groups, while the opposite result was obtained for testosterone. Interestingly, there were Tibetan-specific correlations between glucose levels and Succinivibrio and Sarcina abundance in the intestine. The results of this study suggest that a hypoxic environment could rapidly and lastingly affect both the human intestinal microbiota and blood clinical indexes, providing new insights for the study of plateau adaptability. IMPORTANCE The data presented in the present study demonstrate that the hypoxic plateau environment has a profound impact on the gut microbiota and blood clinical indexes in Han and Tibetan individuals. The plateau-changed signatures of the gut microbiota and blood clinical indexes were not restored to the nonplateau status in the Han cohorts, even when the individuals returned to the plain from the plateau for several months. Our study will improve the understanding of the great impact of hypoxic environments on the gut microbiota and blood clinical indexes as well as the adaptation mechanism and intervention targets for plateau adaptation.

Thermal adaptation plays a fundamental role in the expansion and distribution of insects, and heat shock proteins (Hsps) play important roles in the temperature adaptation of various organisms. To determine the roles of Hsp genes (Hsp70, Hsp21, and sHsp21) on the high temperature tolerance of Agasicles hygrophila, we obtained complete cDNA (complementary DNA) sequences for Hsp70, Hsp21, and sHsp21 by rapid amplification of cDNA ends (RACE), analyzed their expression profiles under different high temperature treatments by quantitative reverse transcription polymerase chain reaction (RT-qPCR), and performed functional verification by RNA interference (RNAi). The open reading frames of Hsp70, Hsp21, and sHsp21 were 1940, 543, and 567 bp, encoding 650, 180, and 188 amino acids, respectively. Their molecular weights (MWs) were 71.757, 20.879, and 21.510 kDa, and the isoelectric points were 5.63, 6.45, and 6.24, respectively. Phylogenetic tree analysis showed that the Hsp70, Hsp21, and sHsp21 genes of A. hygrophila were relatively conserved in evolution. The Hsp70 and Hsp21 genes in A. hygrophila were homologous to those in Leptinotarsa decemlineata (87 and 79% similarity, respectively), and the sHsp21 gene in A. hygrophila was homologous to that in Lissorhoptrus oryzophilus (74% similarity). The amino acid polypeptide chain had highly conserved sequences of DLGGGTFD, VLVGGSTR, and GPTIEEVD. The sequence of EEVD was the characteristic motif of cytoplasmic Hsp70, and the highly conserved sequences of MALFR and MSLLP were characteristic sequences of Hsp2 and sHsp21, respectively. Relative quantitative real time PCR showed that the three Hsps could be induced by 4-h treatment at high temperatures. Significant upregulation of these Hsps was observed when the temperature was further increased. The RNAi results showed that the injection of the three Hsps’ dsRNA could suppress the expression at the gene level significantly. Compared with the control group, high temperature heat shock reduced the fecundity of A. hygrophila significantly, and the fecundity decreased with the increase in temperature. Our results suggest that Hsp70, Hsp21, and sHsp21 might play key roles in high temperature adaptation of A. hygrophila and help improve our understanding of their mechanism of thermotolerance.

As natural gas exploration expands to deep, ultra-deep and unconventional areas, more and more complex exploration targets are encountered. In this circumstance, it is necessary to improve the existing basic natural gas geological theories for guiding the exploration and discovery of more giant gas fields. In this paper, the researches on basic natural gas geological theories since the beginning of the 12th Five-Year Plan were engaged, and then the key exploration target zones were analyzed. Some results were obtained. (1) The theory of whole-process hydrocarbon generation of organic matters was improved and the geologic theories of organic matter hydrocarbon generation (e.g. the thermal evolution model of kerogen degradation and the successive gas generation of organic matters) were developed. (2) Multi-element natural gas genesis identification method, quantitative evaluation method for different types of seals/caprocks, tight sandstone gas accumulation theory for low hydrocarbon generation intensity region, and hydrocarbon accumulation theory for giant ancient carbonate gas field were established, and the geological theories of gas generation, genesis identification and hydrocarbon accumulation were developed to provide the effective guidance for the exploration breakthrough and discovery of giant gas fields in the key basins of China recently. Four conclusions were reached: (1) ancient carbonate rock, tight sandstone, foreland region, shale and volcanic rock are primary exploration targets for discovering giant gas fields; (2) craton and foreland basins are still the key exploration areas, and ancient uplift, gentle slope and thrust belt are the main enrichment zones; (3) ancient strata and deep formations are critical gas exploration targets in the future; (4) oil cracking gas in marine basins, tight sandstone gas and shale gas are the important replacement resources for future gas reserves and production growth. Keywords: Natural gas, Basic geological theory, New progress, Exploration domain, Ancient carbonate rock, Tight sandstone, Craton, Foreland basin, Giant gas field

The Upper Paleozoic in the north part of Tianhuan depression in the Ordos Basin, NW China has lower hydrocarbon generation intensity and complex gas-water relationship, the main factors controlling the formation of tight sandstone gas and the distribution of tight sandstone gas in the low hydrocarbon generation intensity area are studied. Through two-dimensional physical simulation experiment of hydrocarbon accumulation, analysis of reservoir micro-pore-throat hydrocarbon system and dissection of typical gas reservoirs, the evaluation models of gas injection pressure, reservoir physical property, and gas generation threshold were established to determine the features of tight gas reservoirs in low hydrocarbon intensity area: (1) at the burial depth of less than 3 000 m, the hydrocarbon generation intensity of (7−10)×108 m3/km2 is high enough to maintain effective charging; (2) tight sandstone in large scale occurrence is conducive to accumulation of tight gas; (3) differences in reservoir physical property control the distribution of gas pool, for the channel sandstone reservoirs, ones with better physical properties generally concentrate in the middle of sandstone zone and local structural highs; ones with poor physical properties have low gas content generally. Based on the dissection of the gas reservoir in the north Tianhuan depression, the formation of tight gas reservoirs in low hydrocarbon generating intensity area are characterized by “long term continuous charging under hydrocarbon generation pressure, gas accumulation in large scale tight sandstone, pool control by difference in reservoir physical property, and local sweet spot”, and the tight gas pools are distributed in discontinuous “sheets” on the plane. This understanding has been proved by expanding exploration of tight sandstone gas in the north Tianhuan depression. Key words: Ordos Basin, Tianhuan depression, hydrocarbon generation intensity, tight sandstone gas, reservoir-forming mechanism, distribution pattern

The position of the chromatin opening of Bemisia tabaci undergoes significant changes under different temperature stresses, and numerous regulatory factors have been found. In this study, we verified two key factors, cytochrome P450 4C1 and carbonic anhydrase 3. The results showed that invasive whiteflies had a significantly lower heat resistance after silencing BtCYP 4C1 and BtCar3. In addition, whiteflies had a higher cold tolerance after silencing BtCYP 4C1. These results indicate that BtCYP 4C1 and BtCar3 are key regulators in the temperature adaptation of B. tabaci. Moreover, they may be key factors in influencing the geographical distribution and dispersal of B. tabaci as an invasive species in China.

Before 11th five-year plan, geologists proposed the viewpoint that the gas generation intensity that's more than 20 × 108 m3/km2 was an important condition for forming conventional large gas fields. However, recent exploration findings indicate that large-area tight sandstone gas that has a gas generation intensity of less than 20 × 108 m3/km2 can still form reserves. This is an area worth exploring. Through innovative accumulation simulation, microscopic pore throat analysis of reservoirs, and dissection of typical gas reservoirs, several factors have been established, including the comprehensive evaluation models involving gas charging pressure, reservoir physical properties, and lower gas generation limit. In addition, the paper has made it certain that the tight sandstone gas in a low gas generation intensity area has accumulation characteristics such as “partial water displacing, long-term gas supply, gas control by tight reservoirs of scale, gas abundance control by physical properties, combined control and enrichment of dominant resources, etc.”, and has proposed the viewpoint that this area has the accumulation mechanism that of a “non-dominant transportation, long-term continuous charging, reservoir controlling by physical property difference, and enrichment in partial sweet spots” and shows discontinuous “patchy distribution” on the plane. This is of much significance to fine exploration and development of the trillion cubic meter resources of the low gas generation intensity areas in the west of Sulige gas field.

ABSTRACT Human pluripotent stem cells (hPSCs) are an important system to study early human development, model human diseases, and develop cell replacement therapies. However, genetic manipulation of hPSCs is challenging and a method to simultaneously activate multiple genomic sites in a controllable manner is sorely needed. Here, we constructed a CRISPR-ON system to efficiently upregulate endogenous genes in hPSCs. A doxycycline (Dox) inducible dCas9-VP64-p65-Rta (dCas9-VPR) transcription activator and a reverse Tet transactivator (rtTA) expression cassette were knocked into the two alleles of the AAVS1 locus to generate an iVPR hESC line. We showed that the dCas9-VPR level could be precisely and reversibly controlled by the addition and withdrawal of Dox. Upon transfection of multiplexed gRNA plasmid targeting the NANOG promoter and Dox induction, we were able to control NANOG gene expression from its endogenous locus. Interestingly, an elevated NANOG level promoted naïve pluripotent gene expression, enhanced cell survival and clonogenicity, and enabled hESCs to integrate with the inner cell mass (ICM) of mouse blastocysts in vitro. Thus, iVPR cells provide a convenient platform for gene function studies as well as high-throughput screens in hPSCs.

Chemosensory proteins (CSPs) are considered to be the transporter linking odorant chemicals and receptors on sensory neurons. However, the extensive expression patterns of CSPs in insects suggest that CSPs are also involved in other physiological processes; the range of their functions, however, remains uncertain. In this study, we successfully characterized and cloned the CSP12 of Ophraella communa (OcomCSP12). The open reading frame of OcomCSP12 encodes 131 amino acids, with four conserved cysteine residues. The expression patterns of OcomCSP12 validated by quantitative real-time PCR (qRT-PCR) showed that OcomCSP12 is specifically expressed in female ovary. Furthermore, compared with the control treatment, silencing OcomCSP12 resulted in significantly reduced oviposition in females. Surprisingly, the knock-down rate of OcomCSP12 exceeded 95% and remained depressed for more than 15 days, indicating that RNA interference (RNAi) was a suitable method for exploring the function of CSP12 in O. communa. These findings increase our understanding of the expression profile and function of the CSP gene family in insects.

Considering the predicted rising temperatures under current climate change and heat wave scenarios, organisms are expected to suffer more intense and frequent thermal stress. Induced heat is accumulated by organisms and can cause a variety of physiological stress responses. Ophraella communa is an effective biological control agent of common ragweed, Ambrosia artemisiifolia, but the responses of this biocontrol agent to heat stress have not been fully elucidated and, therefore, its potential responses to climate change are uncertain. We investigated the physiological metabolism of subsequent O. communa adults after: (1) different developmental stages (egg, larval, pupal, and adult) were exposed to thermal stress for 3 h each day for 3, 5, 5, and 5 days, respectively (by stage); and (2) individuals were exposed to thermal stress throughout the egg-to-adult period for 3 h each day. The high temperatures of 40, 42, and 44°C were used to induce thermal stress. A control group was reared at 28 ± 2°C. The results showed that short- or long-term exposure to daily phasic high temperatures significantly decreased water and lipid contents and significantly increased glycogen and glycerol contents in all adults (i.e., after exposure of different stages or throughout the egg-to-adult period). However, the total sugar content significantly increased in adults after the eggs and larvae were exposed to brief short-term thermal stress. Compared to the control, the total sugar content was also significantly higher in the adults and pupae exposed to 44°C. Total sugar content in females increased significantly in response to long-term phasic thermal stress at 40°C. However, sugar content of males exposed to 44°C decreased significantly. After long-term phasic thermal stress, water and glycogen contents in males were significantly higher than in females; however, females had higher total sugar and lipid contents. Therefore, our study provides a basic understanding of the metabolic responses of O. communa to thermal stress and offers insights into its potential as a natural biocontrol agent against A. artemisiifolia during the summer season and under predicted climate change scenarios.

Agasicles hygrophila is an effective biological control agent for the invasive weed Alternanthera philoxeroides, and because of this it has been introduced to many parts of the world where A. philoxeroides is a problem. Despite this, there are no reports at present about the reproduction of this important insect. Vitellogenin receptors (VgRs) belong to the superfamily of low-density lipoprotein receptors (LDLRs). One of the roles of VgRs is to regulate the absorption of yolk protein in insects. In this study, the full length vitellogenin receptor gene (AhVgR) from A. hygrophila was sequenced and found to encode a predicted protein of 1,642 amino acids. Sequence analysis of AhVgR revealed that it contains conserved structural motifs common to LDLR family members, and a phylogenetic analysis placed AhVgR as a separate group among the order Coleoptera. AhVgR was found to be specifically expressed in ovarian tissues, and it is first transcribed in the newly-emerged females. The expression patterns are consistent with VgR genes in other insects. RNA interference (RNAi)-mediated suppression of AhVgR gene expression in adult A. hygrophila females inhibited yolk protein deposition in the ovaries, shortened the ovariole, drastically reduced egg production, and ultimately led to a decrease in fecundity. In summary, our work shows that AhVgR is critical for transporting Vg into the oocytes and plays an important role in A. hygrophila reproduction.

The alligatorweed flea beetle Agasicles hygrophila is an insect used for biological control of the aquatic weed Alternanthera philoxeroides (alligatorweed). Because these insects are oviparous, synthesis, and transportation of yolk proteins is integral to reproduction. Vitellin, the chief protein constituent in egg yolk, is mainly synthesized in the fat body and its synthesis is regulated by the transcript levels of Vitellogenin (Vg). In our study, we first cloned and characterized three Vg genes from A. hygrophila and quantified the expression levels of these Vgs in different tissues and developmental stages by RT-qPCR. Analysis of the full-length cDNA sequences of the three A. hygrophila Vg genes revealed that the open reading frames of AhVg1, AhVg2, and AhVg3 were 5175, 5346, and 5385 bp, encoding 1724, 1781, and 1794 amino acids, respectively. RT-qPCR analysis revealed that these three AhVgs have similar expression patterns; expression in the fat body was significantly higher than that in other tissues, and the highest expression was observed in the adult developmental stage. RNA interference was used to explore the functions of the AhVgs. A. hygrophila female adults injected with dsRNA targeting the AhVg genes showed decreased AhVg gene expression. Down regulation of all three AhVgs significantly affected ovary development, reduced egg laying capacity, and reduced the egg hatch rate compared with the control groups. Our findings provide the basis for further study of the functions of Vg genes in other insect species.

The Kuche Depression is considered as the most important gas resource potential and gas exploring area with great gas resource potential and prospect in the Tarim Basin. Based on geochemical experimental analyses and comprehensive geological studies, the general geochemical characteristics of molecular and isotope compositions of rare gases as well as hydrocarbon gases and nonhydrocarbon gases are comparatively studied in the Kuche and Southwestern Depressions. Then, their genetic types are separately identified and gas originations are comprehensively discussed. The main results are as follows. (1) Gas fields in the Kuche Depression have a higher methane abundance, accompanied with low N2 and CO2 abundances, but the Akemomu gas field in the Southwestern Depression has a relatively lower average methane abundance, accompanied with high average N2 and CO2 abundances. The helium abundance of natural gases in gas fields from the Kuche Depression general has 1 order of magnitude higher than the air value. Comparatively, it has more than 2 orders of magnitude higher than the atmospheric value in the Akemomu gas field from the Southwestern Depression. The neon, argon, krypton, and xenon abundances in both Kuche and Southwestern Depressions are lower than the corresponding air values. (2) Natural gases from gas fields in the Kuche Depression and the Southwestern Depressions are generally typical coal-formed gases. The rare gases in the Kuche Depression have typical crustal genesis, mainly deriving from the radioactive decay of elements in the crust, while in the Akemomu gas field from the Southwestern Depression, the rare gases have main crustal genesis with a proportion of 92.5%, probably accompanied with a little mantled genetic contribution. (3) Natural gases in the Kuche Depression are generally derived from coal measure source rocks of Jurassic and Triassic, which principally originated from Jurassic in strata period and coals in source rock types. The Jurassic source rocks account for 55%-75% and the Triassic source rocks account for 25%-45% approximately, while coals occupy 68% and mudstones occupy 32% separately. Natural gases from the Akemomu gas field in the Southwestern Depression mainly originated from humic mudstones of marine and continental transitional source rocks of Carboniferous to Permian.

Ambrosia artemisiifolia is a noxious invasive alien weed, that is harmful to the environment and human health. Ophraella communa is a biocontrol agent for A. artemisiifolia, that was accidentally introduced to the Chinese mainland and has now spread throughout southern China. Recently, we found that upon artificial introduction, O. communa can survive in northern China as well. Therefore, it is necessary to study the cold hardiness of O. communa. Many genes have been identified to play a role in cold-tolerance regulation in insects, but the function of the gene encoding non-muscle myosin regulatory light chain (MRLC-sqh) remains unknown. To evaluate the role played by MRLC-sqh in the cold-tolerance response, we cloned and characterized MRLC-sqh from O. communa. Quantitative real-time PCR revealed that MRLC-sqh was expressed at high levels in the gut and pupae of O. communa. The expression of MRLC-sqh was shown to decrease after cold shock between 10 and 0 °C and ascend between 0 and −10 °C, but these did not show a positive association between MRLC-sqh expression and cold stress. Silencing of MRLC-sqh using dsMRLC-sqh increased the chill-coma recovery time of these beetles, suggesting that cold hardiness was reduced in its absence. These results suggest that the cold hardiness of O. communa may be partly regulated by MRLC-sqh. Our findings highlight the importance of motor proteins in mediating the cold response in insects.

Ophraellacommuna LeSage is an effective biological control agent of common ragweed, Ambrosia artemisiifolia L., which competes with crops and causes allergic rhinitis and asthma. However, thermal stress negatively affects the developmental fitness and body size of this beetle. High temperatures cause a variety of physiological stress responses in insects, which can cause oxidative damage. We investigated the total protein content and activity of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), and peroxidases (PODs) in O. communa adults when its different developmental stages were exposed to high temperatures (40, 42, and 44°C) for 3 h each day for 3, 5, 5, and 5 days, respectively (by stage), and a whole generation to high temperatures (40, 42, and 44°C) for 3 h each day. A control group was reared at 28 ± 2°C. Under short-term daily phasic high-temperature stress, total protein contents were close to the control as a whole; overall, SOD activities increased significantly, CAT activities were closer to or even higher than the control, POD activities increased at 40°C, decreased at 42 or 44°C; stage-specific response was also observed. Under long-term daily phasic high-temperature stress, total protein content increased significantly at 44°C, SOD activities increased at higher temperatures, decreased at 44°C; CAT activities of females increased at ≤42°C, and decreased at 44°C, CAT activities of males decreased significantly; POD activities of females increased at 40°C, decreased at ≥42°C, POD activities of males decreased at 44°C; and antioxidant enzymes activities in females were significantly higher than those in males. Antioxidative enzymes protect O. communa from oxidative damage caused by thermal stress.

Chill tolerance plays a crucial role that allows insect species to adapt to cold environments. Two Chinese geographical populations (Laibin and Yangzhou populations) were selected to understand the chill resistance and evolutionary potential in the Ophraella communa, a biological control agent of the invasive common ragweed, Ambrosia artemisiifolia. Super-cooling point assays, knockdown tests under static low-temperature conditions and determination of glycerol content were studied. ANOVAs indicated significant differences regarding chill coma recovery time, super-cooling point, and glycerol content across populations and sexes. The narrow-sense heritability (h2) estimates of cold resistance based on a parental half-sibling breeding design ranged from 0.39 to 0.53, and the h2 value was significantly higher in the Yangzhou population than in the Laibin population. Additive genetic variances were significantly different from zero for cold tolerance. The Yangzhou population of O. communa has a strong capability to quickly gain resistance to cold. We conclude that the O. communa beetle has a plasticity that can provide cold resistance in the changing climate conditions.