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We aimed to elucidate the characteristics of HIV molecular epidemiology and identify transmission hubs in eastern China using genetic transmission network and lineage analyses. HIV-TRACE was used to infer putative relationships. Across the range of epidemiologically-plausible genetic distance (GD) thresholds (0.1-2.0%), a sensitivity analysis was performed to determine the optimal threshold, generating the maximum number of transmission clusters and providing reliable resolution without merging different small clusters into a single large cluster. Characteristics of genetically linked individuals were analyzed using logistic regression. Assortativity (shared characteristics) analysis was performed to infer shared attributes between putative partners. 1,993 persons living with HIV-1 were enrolled. The determined GD thresholds within subtypes CRF07_BC, CRF01_AE, and B were 0.5%, 1.2%, and 1.7%, respectively, and 826 of 1,993 (41.4%) sequences were linked with at least one other sequence, forming 188 transmission clusters of 2-80 sequences. Clustering rates for the main subtypes CRF01_AE, CRF07_BC, and B were 50.9% (523/1027), 34.2% (256/749), and 32.1% (25/78), respectively. Median cluster sizes of these subtypes were 2 (2-52, n = 523), 2 (2-80, n = 256), and 3 (2-6, n = 25), respectively. Subtypes in individuals diagnosed and residing in Hangzhou city (OR = 1.423, 95% CI: 1.168-1.734) and men who have sex with men (MSM) were more likely to cluster. Assortativity analysis revealed individuals were more likely to be genetically linked to individuals from the same age group (AIage = 0.090, P

Infrared camouflage is an effective technique to avoid many kinds of target detection by detectors in the infrared band. For a high-temperature environment, thermal management of selective emission is crucial to dissipate heat in the mid-infrared non-atmospheric window (5–8 μm). However, it still remains challenges for balancing infrared camouflage and thermal management. Here, we experimentally demonstrate a multilayer film structure (MFS) for infrared camouflage with thermal management. Combining the ideal emission spectrum and genetic algorithm (GA), the inverse-design MFS containing 7 layers of five materials (SiO2, Ge, ZnS, Pt and Au) has been designed. Based on the hierarchical metamaterial, the optimized MFS has high performance of infrared camouflage to against the lidar detection in the near-infrared band. The experimental results reveal the high compatible efficiency among thermal camouflage (ε3–5μm = 0.21, ε8–14μm = 0.16), laser stealth (ε1.06μm = 0.64, ε1.55μm = 0.90, ε10.6μm = 0.76) and thermal management (ε5–8μm = 0.54). Therefore, the proposed MFSs are attractive as basic building block of selective emitter, for the application of advanced photonics such as radiative cooling, infrared camouflage, and thermal emission.

Trophic cascades are important determinants of food web dynamics and functioning, yet mechanisms accounting for variation in trophic cascade strength remain elusive. Here, we used food chain models and a mesocosm experiment (phytoplankton–zooplankton–shrimp) to disentangle the relative importance of two energetic processes driving trophic cascades: primary productivity and energy transfer efficiency. Food chain models predicted that the strength of trophic cascades was increased as the energy transfer efficiency between herbivore and predator (predator efficiency) increased, while its relationship with primary productivity was relatively weak. These model predictions were confirmed by a mesocosm experiment, which showed that the strength of trophic cascade increased with predator efficiency but remained unaffected by nutrient supply rate or primary productivity. Combined, our results indicate that the efficiency of energy transfer along the food chain, rather than the total amount of energy fixed by primary producers, determines the strength of trophic cascades. Our study provides an integrative perspective to reconcile energetic and population dynamics in food webs, which has implications for both ecological research and ecosystem management. [ABSTRACT FROM AUTHOR]

Fitts' law, a predictive model for motor task completion time, is widely utilized in human–computer interaction (HCI) research. While its formulas in two dimensions have achieved consensus over the decades, research diverges on its application in three dimensions. This paper synthesizes practical applications across touchscreens, virtual reality (VR), pedals, handheld devices, etc., with a specific emphasis on enhancing interaction experiences for vulnerable populations. This review studies Fitts' law's applicability in diverse interaction scenarios, highlighting design considerations for touchscreens and handheld/foot-held devices. This article underscores the need for future research to explore three-dimensional applications and consider user age, with potential expansions into medical and sports domains. This systematic review aims to empower designers in crafting more ergonomic products and improving HCI experiences. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB), caused by Fusarium graminearum, causes huge annual economic losses in cereal production. To successfully colonize host plants, pathogens secrete hundreds of effectors that interfere with plant immunity and facilitate infection. However, the roles of most secreted effectors of F. graminearum in pathogenesis remain unclear. We analyzed the secreted proteins of F. graminearum and identified 255 candidate effector proteins by liquid chromatography-mass spectrometry (LC-MS). Five subtilisin-like family proteases (FgSLPs) were identified that can induce cell death in Nicotiana benthamiana leaves. Further experiments showed that these FgSLPs induced cell death in cotton (Gossypium barbadense) and Arabidopsis (Arabidopsis thaliana). A signal peptide and light were not essential for the cell death-inducing activity of FgSLPs. The I9 inhibitor domain and the entire C-terminus of FgSLPs were indispensable for their self-processing and cell death-inducing activity. FgSLP-induced cell death occurred independent of the plant signal transduction components BRI-ASSOCIATED KINASE 1 (BAK1), SUPPRESSOR OF BIR1 1 (SOBIR1), ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1), and PHYTOALEXIN DEFICIENT 4 (PAD4). Reduced virulence was observed when FgSLP1 and FgSLP2 were simultaneously knocked out. This study reveals a class of secreted toxic proteins essential for F. graminearum virulence. Five subtilisin-like proteases among the secreted proteins of Fusarium graminearum induce plant cell death and contribute to F. graminearum virulence. [ABSTRACT FROM AUTHOR]

Gas turbines operate under harsh conditions of high temperature and pressure for extended periods, inevitably experiencing performance degradation. Predicting the performance degradation trend of gas turbines and optimizing planned maintenance cycles are crucial for the economic and safety aspects of gas turbine operation. In this study, a novel data-driven approach for predicting gas turbine performance degradation is proposed. Initially, gas turbine operating data are augmented using a mechanism model. Subsequently, a data-driven performance model is constructed based on support vector regression (SVR) and gas turbine operational characteristics, enabling real-time calculation of performance degradation indicators. Building on this, an Autoregressive Neural Network (AR-Net) is employed to construct a model for predicting the trend of performance degradation. The proposed method is applied to predict performance degradation caused by fouling in the compressor of a gas turbine. Comparative analysis with three other performance degradation prediction methods indicates that the proposed approach accurately identifies the performance degradation trend of gas turbines, determining the optimal maintenance timing. This holds significant importance for the condition-based maintenance of gas turbines. [ABSTRACT FROM AUTHOR]

Summary: Nuclear pore complex (NPC) is composed of multiple nucleoporins (Nups). A plethora of studies have highlighted the significance of NPC in plant immunity. However, the specific roles of individual Nups are poorly understood.NUCLEAR PORE ANCHOR (NUA) is a component of NPC. Loss of NUA leads to an increase in SUMO conjugates and pleiotropic developmental defects in Arabidopsis thaliana. Herein, we revealed that NUA is required for plant defense against multiple pathogens.NUCLEAR PORE ANCHOR associates with the transcriptional corepressor TOPLESS‐RELATED1 (TPR1) and contributes to TPR1 deSUMOylation. Significantly, NUA‐interacting protein EARLY IN SHORT DAYS 4 (ESD4), a SUMO protease, specifically deSUMOylates TPR1. It has been previously established that the SUMO E3 ligase SAP AND MIZ1 DOMAIN‐CONTAINING LIGASE 1 (SIZ1)‐mediated SUMOylation of TPR1 represses the immune‐related function of TPR1. Consistent with this notion, the hyper‐SUMOylated TPR1 in nua‐3 leads to upregulated expression of TPR1 target genes and compromised TPR1‐mediated disease resistance.Taken together, our work uncovers a mechanism by which NUA positively regulates plant defense responses by coordination with ESD4 to deSUMOylate TPR1. Our findings, together with previous studies, reveal a regulatory module in which SIZ1 and NUA/ESD4 control the homeostasis of TPR1 SUMOylation to maintain proper immune output. [ABSTRACT FROM AUTHOR]

Performing online damage evaluation of blades subjected to complex cyclic loads based on the operating state of a gas turbine enables real-time reflection of a blade's damage condition. This, in turn, facilitates the achievement of predictive maintenance objectives, enhancing the economic and operational stability of gas turbine operations. This study establishes a hybrid model for online damage evaluation of gas turbine blades based on their operational state. The model comprises a gas turbine performance model based on thermodynamic simulation, a component load calculation model based on a surrogate model, an updated cycle counting method based on four-point rainflow, and an improved damage mechanism evaluation model. In the new model, the use of a surrogate model for the estimation of blade loading information based on gas turbine operating parameters replaces the conventional physical modeling methods. This substitution enhances the accuracy of blade loading calculations while ensuring real-time performance. Additionally, the new model introduces an updated cycle counting method based on four-point rainflow and an improved damage mechanism evaluation model. In the temperature counting part, a characteristic stress that represents the stress information during the cyclic process is proposed. This inclusion allows for the consideration of the impact of stress fluctuations on creep damage, thereby enhancing the accuracy of the fatigue damage assessment. In the stress counting part, the model incorporates time information associated with each cycle. This concept is subsequently applied in determining the identified cyclic strain information, thereby improving the accuracy of the fatigue damage evaluation. Finally, this study applies the new model to an online damage evaluation of a turbine stationary blade using actual operating data from a micro gas turbine. The results obtained from the new model are compared with the EOH recommended by the OEM, validating the accuracy and applicability of the new model. [ABSTRACT FROM AUTHOR]

The failure of gas turbines' hot components due to fatigue significantly affects their efficient and stable operation. Conducting online damage assessment of components subjected to complex cyclic loads based on the working conditions of gas turbines can provide real-time reflection of component fatigue damage and achieve the purpose of predictive maintenance. In this study, we propose an online cycle counting method that considers temperature fluctuations during the cycle process. Our method is based on the four-point online rainflow counting method by coupling the counting variable with time, introducing the concept of the duration time for full cycles and half cycles, and incorporating a characteristic temperature that better represents the temperature information during the cycle process. With reference to the characteristic temperature, our proposed method comprehensively considers the form and parameters of subsequent life assessment models. This paper provides a detailed explanation of the proposed method and applies it to the fatigue damage assessment of turbine vanes in a micro gas turbine, thereby verifying its accuracy and applicability. [ABSTRACT FROM AUTHOR]

While the relationship between food web complexity and stability has been well documented, how complexity affects productivity remains elusive. In this study, we combine food web theory and a data set of 149 aquatic food webs to investigate the effect of complexity (i.e. species richness, connectance, and average interaction strength) on ecosystem productivity. We find that more complex ecosystems tend to be more productive, although different facets of complexity have contrasting effects. A higher species richness and/or average interaction strength increases productivity, whereas a higher connectance often decreases it. These patterns hold not only between realized complexity and productivity, but also characterize responses of productivity to simulated declines of complexity. Our model also predicts a negative association between productivity and stability along gradients of complexity. Empirical analyses support our predictions on positive complexity‐productivity relationships and negative productivity‐stability relationships. Our study provides a step forward towards reconciling ecosystem complexity, productivity and stability. [ABSTRACT FROM AUTHOR]

Simple Summary: Blood-based circulating cell-free DNA (cfDNA) biomarkers are important for cancer detection because they can provide a less invasive and more cost-effective way of detecting cancer and offer the possibility of screening large populations at risk for the early detection of multiple cancers. However, highly sensitive techniques are needed to detect circulating tumour DNA (ctDNA), and further optimization and standardization of pre-analytical and analytical steps are required to harness the full potential of cfDNA analysis. Blood-based detection of circulating cell-free DNA (cfDNA) is a non-invasive and easily accessible method for early cancer detection. Despite the extensive utility of cfDNA, there are still many challenges to developing clinical biomarkers. For example, cfDNA with genetic alterations often composes a small portion of the DNA circulating in plasma, which can be confounded by cfDNA contributed by normal cells. Therefore, filtering out the potential false-positive cfDNA mutations from healthy populations will be important for cancer-based biomarkers. Additionally, many low-frequency genetic alterations are easily overlooked in a small number of cfDNA-based cancer tests. We hypothesize that the combination of diverse types of cancer studies on cfDNA will provide us with a new perspective on the identification of low-frequency genetic variants across cancer types for promoting early diagnosis. By building a standardized computational pipeline for 1358 cfDNA samples across seven cancer types, we prioritized 129 shard genetic variants in the major cancer types. Further functional analysis of the 129 variants found that they are mainly enriched in ribosome pathways such as cotranslational protein targeting the membrane, some of which are tumour suppressors, oncogenes, and genes related to cancer initiation. In summary, our integrative analysis revealed the important roles of ribosome proteins as common biomarkers in early cancer diagnosis. [ABSTRACT FROM AUTHOR]

Occupying 7% of the World's forest area, plantation forests have been increasing globally for the past 30 years and serve as a natural climate solution. However, whether plantation forests share the same fate as natural forests under the changing climate remains an open question. By establishing a framework in which climate directly and indirectly triggers or exacerbates fire and pests to affect forest vitality, we compared the vitality and resilience of 705 large plantation patches and 187 large natural forest patches over the past 20 years in China. Overall, large patches of plantation forests showed consistent sustainability with natural forests across China and were mainly distributed in humid areas with the fewest and weakest droughts. Forty percent of the vitality decline of natural forests was explained by droughts, pests, and fires driven by climate, while 70% of the vitality decline of plantation forests was affected by a combination of these disturbances through different pathways. As the site environments became drier, an increasing number of plantation forests showed lower vitality relative to natural forests. Frequent and serious droughts not only magnified the direct impact of drought on plantation forests, possibly due to homogeneous forest structure regarding ages and species, but also exacerbated forest fires and caused lower vitality of 85% of plantation forests relative to natural forests in southwest China. The work highlighted threats to the sustainability of plantation forests in site environments with frequent drought, challenging the efforts of expanding plantation forests. [ABSTRACT FROM AUTHOR]

Understanding the formation of feeding links provides insights into processes underlying food webs. Generally, predators feed on prey within a certain body‐size range, but a systematic quantification of such feeding niches is lacking. We developed a size‐constrained feeding‐niche (SCFN) model and parameterized it with information on both realized and non‐realized feeding links in 72 aquatic and 65 terrestrial food webs. Our analyses revealed profound differences in feeding niches between aquatic and terrestrial predators and variation along a temperature gradient. Specifically, the predator–prey body‐size ratio and the range in prey sizes increase with the size of aquatic predators, whereas they are nearly constant across gradients in terrestrial predator size. Overall, our SCFN model well reproduces the feeding relationships and predation architecture across 137 natural food webs (including 3878 species and 136,839 realized links). Our results illuminate the organisation of natural food webs and enables novel trait‐based and environment‐explicit modelling approaches. [ABSTRACT FROM AUTHOR]

The effects of dispersal on spatial synchrony and population variability have been well documented in theoretical research, and a growing number of empirical tests have been performed. Yet a synthesis is still lacking. Here, we conducted a meta-analysis of relevant experiments and examined how dispersal affected spatial synchrony and temporal population variability across scales. Our analyses showed that dispersal generally promoted spatial synchrony, and such effects increased with dispersal rate and decreased with environmental correlation among patches. The synchronizing effect of dispersal, however, was detected only when spatial synchrony was measured using the correlation-based index, not when the covariance-based index was used. In contrast to theoretical predictions, the effect of dispersal on local population variability was generally nonsignificant, except when environmental correlation among patches was negative and/or the experimental period was long. At the regional scale, while low dispersal stabilized metapopulation dynamics, high dispersal led to destabilization. Overall, the sign and strength of dispersal effects on spatial synchrony and population variability were modulated by taxa, environmental heterogeneity, type of perturbations, patch number, and experimental length. Our synthesis demonstrates that dispersal can affect the dynamics of spatially distributed populations, but its effects are context dependent on abiotic and biotic factors. [ABSTRACT FROM AUTHOR]

Understanding the history and regional singularities of human impact on vegetation is key to developing strategies for sustainable ecosystem management. In this study, fossil and modern pollen datasets from China are employed to investigate temporal changes in pollen composition, analogue quality, and pollen diversity during the Holocene. Anthropogenic disturbance and vegetation's responses are also assessed. Results reveal that pollen assemblages from non‐forest communities fail to provide evidence of human impact for the western part of China (annual precipitation less than 400 mm and/or elevation more than 3000 m.a.s.l.), as inferred from the stable quality of modern analogues, principal components, and diversity of species and communities throughout the Holocene. For the eastern part of China, the proportion of fossil pollen spectra with good modern analogues increases from ca. 50% to ca. 80% during the last 2 millennia, indicating an enhanced intensity of anthropogenic disturbance on vegetation. This disturbance has caused the pollen spectra to become taxonomically less diverse over space (reduced abundances of arboreal taxa and increased abundances of herbaceous taxa), highlighting a reduced south–north differentiation and divergence from past vegetation between regions in the eastern part of China. We recommend that care is taken in eastern China when basing the development of ecosystem management strategies on vegetation changes in the region during the last 2000 years, since humans have significantly disturbed the vegetation during this period. [ABSTRACT FROM AUTHOR]

The nanostructure composed of nanomaterials and subwavelength units offers flexible design freedom and outstanding advantages over conventional devices. In this paper, a multifunctional nanostructure with phase-change material (PCM) is proposed to achieve tunable infrared detection, radiation cooling and infrared (IR)-laser compatible camouflage. The structure is very simple and is modified from the classic metal–dielectric–metal (MIM) multilayer film structure. We innovatively composed the top layer of metals with slits, and introduced a non-volatile PCM Ge2Sb2Te5 (GST) for selective absorption/radiation regulation. According to the simulation results, wide-angle and polarization-insensitive dual-band infrared detection is realized in the four-layer structure. The transformation from infrared detection to infrared stealth is realized in the five-layer structure, and laser stealth is realized in the atmospheric window by electromagnetic absorption. Moreover, better radiation cooling is realized in the non-atmospheric window. The proposed device can achieve more than a 50% laser absorption rate at 10.6 μm while ensuring an average infrared emissivity below 20%. Compared with previous works, our proposed multifunctional nanostructures can realize multiple applications with a compact structure only by changing the temperature. Such ultra-thin, integratable and multifunctional nanostructures have great application prospects extending to various fields such as electromagnetic shielding, optical communication and sensing. [ABSTRACT FROM AUTHOR]

In this paper, a dynamic color-variable solar absorber is designed based on the phase change material Sb2Se3. High absorption is maintained under both amorphous Sb2Se3 (aSb2Se3) and crystalline Sb2Se3 (cSb2Se3). Before and after the phase transition leading to the peak change, the structure shows a clear color contrast. Due to peak displacement, the color change is also evident for different crystalline fractions during the phase transition. Different incident angles irradiate the structure, which can also cause the structure to show rich color variations. The structure is insensitive to the polarization angle because of the high symmetry. At the same time, different geometric parameters enable different color displays, so the structure can have good application prospects. [ABSTRACT FROM AUTHOR]

The advanced coupled conversion technique based on the oxidative dehydrogenation (ODH) of alcohols and the reduction of CO2 is a potential strategy to solve the current energy and environmental crisis, and is of great significance for the upgrading conversion of CO2 to fuels. This work discloses that the Al3+ species-doped decatungstates (Al-DTs) can efficiently catalyze the coupled conversion of various aliphatic and aromatic primary/secondary alcohols with CO2 in MeCN under visible light illumination and very mild conditions, and the reductive efficiency of CO2 depends on the doping levels of Al3+ species in Al-DTs and the ODH reactivity of alcohols. After continuously illuminating for 12 h, the best, 4% Al-DT can provide 437 μmol acetophenone as the ODH product and 218 μmol CO2 reduction products (formic acid and methanol) with 1.82 h−1 turnover frequency in the photocatalytic coupled conversion of α-phenylethanol with CO2. Also, a trace amount of CO is detected from the photocatalytic coupled reactions. UV-vis spectra and isotope tracing tests using heavy oxygen water (H218O) support that the doubly-reduced blue H2DT species generated from the photocatalytic ODH of alcohols turns into its oxygen-deficient form ([DT2−]v) via an intra-molecular dehydration or lattice oxygen transfer and the latter, with the help of doped Al3+ species, may efficiently reduce CO2 to fuels via the multi-step proton-coupled electron transfer (PET) pathway. [ABSTRACT FROM AUTHOR]

Understanding the processes that stabilize species populations is a fundamental question in ecology and central to conservation biology. In metapopulations, dispersal can act as a 'double edged' sword for species stability by simultaneously decreasing local population variability (thereby decreasing local extinction risk) while increasing spatial synchrony (thereby increasing landscape‐level extinction risk). These dynamics may operate at different timescales, complicating efforts to assess their relative importance for long‐term stability. Here, we use a simple metapopulation model to understand how dispersal affects population variability and spatial synchrony across timescales. Our model shows that dispersal has contrasting effects at short versus long timescales on the variability and synchrony of populations. For populations that exhibit slow recovery when perturbed (i.e. under‐compensatory growth), dispersal decreases local population variability while increasing spatial synchrony at long timescales. In contrast, at short timescales dispersal increases local population variability while decreasing spatial synchrony. For populations that recover via damped oscillation when perturbed (i.e. over‐compensatory growth), the effects of dispersal are all opposite to those for populations with under‐compensatory growth, at both short and long timescales. The timescale‐dependent effect of dispersal has important implications for empirical studies. Specifically, studies conducted over short periods may only observe population variability increasing and spatial synchrony decreasing with dispersal, whereas the opposite patterns may predominate over longer periods. Our results provide novel insights on the dynamics underlying the role of dispersal and highlight the importance of time series length in empirical studies of metapopulations. [ABSTRACT FROM AUTHOR]

Summary: Nucleotide‐binding site (NBS)–leucine‐rich repeat (LRR) domain receptor (NLR) proteins play important roles in plant innate immunity by recognizing pathogen effectors. The Toll/interleukin‐1 receptor (TIR)‐NBS (TN) proteins belong to a subtype of the atypical NLRs, but their function in plant immunity is poorly understood. The well‐characterized Arabidopsis thaliana typical coiled‐coil (CC)‐NBS‐LRR (CNL) protein Resistance to Pseudomonas syringae 5 (RPS5) is activated after recognizing the Pseudomonassyringae type III effector AvrPphB. To explore whether the truncated TN proteins function in CNL‐mediated immune signaling, we examined the interactions between the Arabidopsis TN proteins and RPS5, and found that TN13 and TN21 interacted with RPS5. However, only TN13, but not TN21, was involved in the resistance to P. syringae pv. tomato (Pto) strain DC3000 carrying avrPphB, encoding the cognate effector recognized by RPS5. Moreover, the regulation of Pto DC3000 avrPphB resistance by TN13 appeared to be specific, as loss of function of TN13 did not compromise resistance to Pto DC3000 hrcC− or Pto DC3000 avrRpt2. In addition, we demonstrated that the CC and NBS domains of RPS5 play essential roles in the interaction between TN13 and RPS5. Taken together, our results uncover a direct functional link between TN13 and RPS5, suggesting that TN13 acts as a partner in modulating RPS5‐activated immune signaling, which constitutes a previously unknown mechanism for TN‐mediated regulation of plant immunity. Significance Statement: In this study, we found that the truncated nucleotide‐binding site (NBS)–leucine‐rich repeat (LRR) domain receptor (NLR) protein TN13 associated with the well‐characterized coiled‐coil (CC)‐NBS‐LRR (CNL)‐type NLR protein RPS5 in Arabidopsis. TN13 specifically modulated RPS5‐mediated resistance to Pseudomonas syringae expressing the effector avrPphB, suggesting that TN13 may act as a partner protein in RPS5‐activated immunity. These data uncover a direct link between TIR‐NBS (TN) and CNL proteins, and imply that there is a functional network among diverse NLR proteins regulating plant immunity. [ABSTRACT FROM AUTHOR]

Aedes albopictus is the only vector that can transmit the dengue virus in Zhejiang Province, central China, and it can develop insecticide resistance due to long-term exposure to pyrethroids. The presence of knockdown resistance (kdr) mutations is one of the mechanisms responsible for pyrethroid resistance, and has been reported in some Ae. albopictus populations in southern China. However, little is known about the DNA diversity of the voltage-gated sodium channel (VGSC) gene in Ae. albopictus populations in central China. Four Ae. albopictus field populations were collected, in Yiwu (YW), Quzhou (QZ), Wenzhou (WZ), and Jiaxing (JX) from Zhejiang Province, central China. The susceptibility of Ae. albopictus adults to three pyrethroids (beta-cypermethrin, deltamethrin, and permethrin) was tested using the WHO tube assay, and Kdr mutations were identified via PCR and sequencing. The relationship between kdr mutations and pyrethroid phenotypes was also analyzed. Of the four populations, none was sensitive to any pyrethroid tested, and the YW population showed the strongest pyrethroid resistance. Non-synonymous kdr mutations were detected in codons 1532 and 1534, domain III. At codon 1534, one mutant allele, TCC(S), was detected in the four populations with a frequency of 42.08%, while at codon 1532, one mutant allele, ACC(T), was detected in the JX and QZ populations, with frequencies of 4.22 and 3.03%, respectively. The F1534S mutant allele was positively correlated with both beta-cypermethrin and deltamethrin resistance phenotypes (OR > 1, P < 0.05), whereas the I1532T mutant allele was possibly negatively correlated with beta-cypermethrin, deltamethrin, and permethrin resistance phenotypes (OR < 1, P > 0.05). In conclusion, resistance and resistance mutations regarding to three pyrethroids are already present in the Ae. Albopictus populations from Zhejiang, central China, which prompts the need to use non-insecticide-based methods of insect control. [ABSTRACT FROM AUTHOR]

Food webs capture the trophic relationships and energy fluxes between species, which has fundamental impacts on ecosystem functioning and stability. Within a food web, the energy flux distribution between a predator and its prey species is shaped by food quantity–quality trade‐offs and the contiguity of foraging. But the distribution of energy fluxes among prey species as well as its drivers and implications remain unclear.Here we used 157 aquatic food webs, which contain explicit energy flux information, to examine whether a predator's foraging is asymmetric and biased towards lower or higher trophic levels, and how these patterns may change with trophic level. We also evaluate how traditional topology‐based approaches may over‐ or under‐estimate a predator's trophic level and omnivory by ignoring the asymmetric foraging patterns.Our results demonstrated the prevalence of asymmetric foraging in natural aquatic food webs. Although predators prefer prey at higher trophic levels with potentially higher food quality, they obtain their energy mostly from lower trophic levels with a higher food quantity. Both tendencies, that is, stronger feeding preference for prey at higher trophic levels and stronger energetic reliance on prey at lower trophic levels are alleviated for predators at higher trophic levels.The asymmetric foraging lowers trophic levels and omnivory at both species and food web levels, compared to estimates from traditional topology‐based approaches. Such overestimations by topology‐based approaches are most pronounced for predators at lower trophic levels and communities with higher number of trophic species.Our study highlights the importance of energy flux information in understanding the foraging behaviour of predators as well as the structural complexity of natural food webs. The increasing availability of flux‐based food web data will thus provide new opportunities to reconcile food web structure, functioning and stability. [ABSTRACT FROM AUTHOR]

To analyze the results of HIV screening and the HIV-positive rate based on different HIV detection strategies in Zhejiang Province, China. Data were downloaded from the AIDS Prevention and Control Information System on May 1, 2019. HIV screening, prevalence, and incidence data were analyzed from 2008 to 2018. The incidence of HIV was calculated from the results of BED testing. SPSS software (ver. 19.0) was used for the analysis. The number of people screened for HIV increased by 229.7% from 2008 to 2018, while the incidence of HIV increased from 1.14‱ (2010) to 1.67‱ (2018), peak by 2015 (2.28‱). The proportion of people screened for HIV in medical institutions increased from 62.0% in 2008 to 67.1% in 2018, while of all positive tests, 47.9% were conducted at medical institutions in 2008, which increased to 63.2% in 2018. VCT and STD clinic attendees, who had only 4.5% of all those undergoing HIV tests, accounted for 23.7% of all HIV positive in 2018. The rate of HIV-positive people and incidence of HIV both increased in Zhejiang Province between 2008 and 2015. The most effective strategy for detecting HIV new cases is screening visitors to VCT and STD clinics. [ABSTRACT FROM AUTHOR]

Background The purpose of this study was to research the molecular transmission and genetic evolutionary characteristics among CRF07_BC-infected patients in a developed area in Eastern China. Methods Plasma samples from newly diagnosed HIV-1-positive patients from 2015–2018 and basic demographic and epidemiological information were obtained. Pol sequences from CRF07_BC-infected patients were selected for phylogenetic, molecular transmission network, and Bayesian evolutionary analyses. Results Pol sequences were successfully obtained from 258 samples of CRF07_BC. Phylogenetic analysis revealed 2 distinct lineages: lineage 1 (66.3%, 171/258), primarily from men who have sex with men (MSM) and some heterosexual individuals, and lineage 2 (33.7%, 87/258), primarily from heterosexual individuals. Under an optimal genetic distance of 0.01 substitutions/site, 163 individuals (63.2%, 163/258) formed 23 groups comprising 6 clusters and 17 dyads in the networks. A distinctly large and rapidly growing cluster (C1) containing 105 individuals was identified, in which MSM with ≥4 links had quite a high transmission risk (low educational background, active sexual behavior, low sexual protection awareness, etc.). According to Bayesian analyses, most C1 clades formed from 2005 to 2009, most of which were closely geographically related to CRF07_BC epidemic strains from Anhui province. Conclusions Here, we elucidated the local transmission characteristics and epidemic pattern of HIV-1 CRF07_BC, revealing that MSM (especially with ≥4 links) may be a significant driver in the formation of active and rapid growth networks in regional CRF07_BC epidemics. Thus, unique region– and risk group–specific transmission network analysis based on a molecular approach can provide critical and insightful information for more effective intervention strategies to limit future HIV-1 transmission. [ABSTRACT FROM AUTHOR]

Despite the implementation of health education and free condom distribution for decades, the HIV/AIDS epidemic among older adults in China shows no sign of declining. This study aims to identify HIV transmission patterns and pathways in a rural county area and provide insight for developing effective HIV prevention strategies among older adults. Epidemiological field surveys combined with phylogenetic analysis were used to identify potential HIV transmission linkage in one rural county with a rapidly increasing HIV epidemic among older adults. A total of 160 HIV-positive individuals and their HIV-positive sexual partners diagnosed between 2015 and 2018 were recruited. Among them, 69.4% (n = 111) were diagnosed at age 50 or older, 68.1% (n = 109) were men, and 55.0% (n = 88) were married. Ninety-six participants self-reported as having been infected with HIV through commercial heterosexual behavior and 24 were infected from their HIV-positive spouse. CRF08_BC (67.0%, n = 73) and CRF07_AE (19.3%, n = 21) were the prevalent HIV stains and formed 15 clusters at distance cutoff of 0.0025. Participants diagnosed with HIV at age ≥50, those who were divorced or bereft their spouse, or infected with HIV locally were more prevalent within the 15 molecular clusters. We identified specific venues as the primary hotspot and found that commercial heterosexual contact between older men and commercial sex workers contributed to the local HIV epidemic. In rural areas with an increasing HIV epidemic, detecting HIV transmission clusters through epidemiological and phylogenetic analysis as well as designing localized HIV prevention strategies should be prioritized. [ABSTRACT FROM AUTHOR]