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During infrared detection, the thermal radiation from the background generates substantial photon noise and thus severely limit the capability of an infrared detector to identify a target. Going beyond this limitation has been a long‐standing challenge in the development of infrared detectors. This paper proposes to break this limitation by creating a narrow photoresponse band with a high peak responsivity to reject the background radiation and enhance the responsivity to the target with characteristic emission lines. This scheme is numerically demonstrated in a dimerized grating integrated quantum well infrared photodetector, based on critical coupling with a Brillouin zone folding induced quasi‐bound state in the continuum (BIC). The asymmetric deformation of the grating structure folds the photonic band and generates a quasi‐BIC with a tunable high radiation Q factor (QR) at the Γ point. By reducing the doping concentration of the quantum wells for a high absorption Q factor (QA) and tuning the QR to make QR = QA for critical coupling, a narrowband photoresponse with a high peak responsivity is achieved and the background‐limited specific detectivity of 4.55 × 1012 cm Hz1/2 W−1 is obtained for a 2π field of view, surpassing the ideal‐photoconductor limit by 92 times. [ABSTRACT FROM AUTHOR]

Summary: The primary objective of this paper is to enhance the efficient utilization of communication resources. To achieve this, the paper delves into the disturbance observer based adaptive heading control strategy for Unmanned Marine Vehicles with event‐triggered and input quantization. Furthermore, in order to mitigate the impact of slow time‐varying external disturbances within the control system, the disturbance observer is employed for estimation. Within the context of a networked control, control input is subjected to quantization via an input quantizer, and the process of input quantization is described by using a linear analytical model. Importantly, no foreknowledge of quantization parameters is necessary for the quantized feedback controllers. Subsequently, the sliding mode control method is combined with event‐triggered mechanismss to design quantization feedback control system. The stability of the closed‐loop system is established in line with the fundamental tenets of Lyapunov stability theory, validating the bounded nature of both observation and heading tracking control errors. The effectiveness of the proposed heading control scheme is further underscored through a series of simulation experiments. [ABSTRACT FROM AUTHOR]

Summary: This article delves into the adaptive heading tracking control of unmanned surface vehicle (USV) by incorporating an event‐triggered mechanism and signal quantization. The primary objective is to save communication resources while alleviating the burden of signal transmission. To address time‐varying external perturbations inherent in the control system, a disturbance observer is employed for precise estimation. Additionally, a linear model is introduced to delineate the procedure of quantization. By furnishing the controller with purpose‐designed quantized control input, the adaptive tracking control system can effectively track desired input without requiring any prior knowledge of the quantized parameters. The article substantiates its claims by demonstrating the system's stability in the absence of quantization considerations and the bounded nature of quantization errors through a series of presented lemmas. Further, the stability of the USV heading control system, integrated with an event‐triggered mechanism and signal quantization, is proofed in accordance with Lyapunov stability theory. Finally, the proposed strategy's efficacy and practical applicability are validated through experimental simulations. [ABSTRACT FROM AUTHOR]

Climatic wetting‐drying cycles exacerbated by climate change can trigger several weakening mechanisms in surface soils, potentially leading to instability and failure of slopes and earthen structures. This study proposes a bio‐mediated approach based on microbially induced calcite precipitation (MICP) to increase soil resilience to wetting‐drying cycles. To explore its viability and the underlying mechanisms, we conducted a series of laboratory tests on clayey soil that underwent six wetting‐drying cycles. The tests were conducted with different treatment methods to investigate the effect of treatment sequence and cementation solution concentration. After MICP treatment, the initial evaporation rate, surface crack ratio during drying, and total soil weight loss during rainfall erosion were reduced by up to 32%, 85%, and 90%, respectively. Spraying the cementation solution first in the MICP treatment sequence proves more effective in improving soil water retention capacity. On the other hand, initiating the sequence with the bacterial solution demonstrates a more pronounced effect in reducing soil desiccation cracks and erosion. Microstructure analysis reveals that the content and distribution of CaCO3 precipitation are the major factors controlling the effectiveness of MICP for the cementation of clayey soil. Employing MICP can minimize the carbon footprint and contribute to developing environmentally friendly solutions for soil improvement in regions affected by climatic wetting‐drying cycles. Plain Language Summary: The rising frequency and intensity of climatic wetting‐drying cycles driven by climate change pose a threat to surface soil stability, consequently increasing the risk of land degradation, soil erosion, landslide, and other forms of ground instabilities and failures. This study presents a bio‐mediated approach using microbially induced calcite precipitation to enhance soil resilience to wetting‐drying cycles. Experimental results show that MICP is capable of improving soil properties related to water retention, desiccation resistance, and erosion control. The microstructure analysis further elucidates the role of MICP‐induced CaCO3 precipitation in cementing clayey soil and demonstrates that the bio‐created buffer barrier significantly mitigates the adverse effect of climatic wetting‐drying cycles on surface soil. This study is expected to offer an environmentally friendly and sustainable soil improvement solution in regions impacted by cascading climatic extremes. Key Points: A sustainable bio‐mediated approach using microbially induced calcite precipitation (MICP) was applied to enhance soil resilience to climatic wetting‐drying cyclesMICP significantly improves water retention, desiccation and erosion resistance of surface soilThis study provides new insights into the fundamental mechanisms of the interaction between climate and MICP‐treated soil [ABSTRACT FROM AUTHOR]

BACKGROUND: Sex pheromones have proven to be a viable tool for monitoring and controlling pests and is an important part of integrated pest management (IPM). The noctuid moth Macdunnoughia crassisigna Warren poses a significant threat as a defoliator pest, impacting soybean and cruciferous vegetable production and quality in East Asia. However, a lack of comprehensive knowledge about its sexual chemical signaling hampers the development of semiochemical‐based IPM approaches for M. crassisigna. RESULTS: We first determined the mating rhythms of M. crassisigna. We then collected pheromones from the sex glands of virgin females at the mating peak and analyzed their components using gas chromatography–electroantennogram detection analysis. The results showed that three components elicited significant electrophysiological responses in male antennae. Gas chromatography–mass spectrometry analysis characterized these components as (Z)‐7‐dodecene acetate (Z7‐12:OAc), (Z)‐9‐tetradecene acetate (Z9‐14:OAc), and (Z)‐11‐hexadecen‐1‐ol (Z11‐16:OH). Further field experiments indicated that the mixture of Z7‐12:OAc and Z9‐14:OAc at a ratio of 3:1 displayed significant attractivity to males, confirming its role as a putative sex pheromone of M. crassisigna. Long‐term monitoring tests showed that traps baited with these pheromone lures effectively mirrored the population dynamics of M. crassisigna. CONCLUSION: This study successfully identified and validated the sex pheromone released by female M. crassisigna and formulated potent sex lures for field‐based pest monitoring. These findings enriched our understanding of chemical communication in Noctuidae and laid a foundation for developing practical monitoring and control methods against M. crassisigna. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

While the western part of northern Tarim Craton has long been considered as a Paleozoic passive margin, a pronounced Silurian‐Devonian magmatism developed on eastern part of this margin may indicate different but active margin setting. In this contribution, detailed structural mapping, petro‐structural analysis, and geochronological investigations were conducted in the Korla area, eastern part of northern Tarim Craton. Three main generations of fabrics were recognized. The earliest pervasive fabric is an originally sub‐horizontal metamorphic S1 foliation that is in part associated with migmatization characterized by high temperature/low pressure metamorphic mineral assemblages, interpreted as reflecting crustal extension. S1 foliation was affected by D2 contraction forming regional‐scale F2 upright folds associated with sub‐vertical axial planar foliation S2. D3 is marked by development of NW‐SE oriented dextral fault, asymmetric mega‐folding of S2 and spaced NW‐SE‐striking S3 foliation, likely in response to dextral transpression. Geochronological data indicate that D1 extension occurred from ca. 420 to 410 Ma, D2 contraction started around 410 Ma and lasted till 400 Ma or later, and D3 transpression was ongoing around ∼370 Ma. Integrated with regional data, an updated geodynamic model is proposed by interpreting the Central Tianshan, South Tianshan and NE Tarim Craton as an early Paleozoic supra‐subduction system. We suggest that the Silurian‐Devonian event reflects thermal softening and horizontal stretching of the supra‐subduction crust, resulting in drifting of the Central Tianshan continental arc from the proto Tarim Craton in association with opening of the South Tianshan back‐arc basin in‐between. Key Points: NE Tarim Craton formed a sub‐horizontal HT/LP foliation in response to crustal extension in the late Silurian‐early DevonianThinned and thermally softened northern Tarim margin was affected by middle Devonian shorteningEarly Paleozoic northern Tarim, South Tianshan, and Central Tianshan evolved into one supra‐subduction environment [ABSTRACT FROM AUTHOR]

Structural and metamorphic effects of a Devonian extension‐shortening cycle in the NW Chinese Altai were investigated using combined structural‐petrological analysis and zircon and monazite U‐Pb geochronology. Structural observations revealed a ubiquitous, sub‐horizontal metamorphic fabric (S1), which was originally sub‐parallel with horizontal bedding (S0) of supracrustal Devonian volcanic‐sedimentary basins. This metamorphic fabric is defined by a sillimanite‐bearing migmatitic gneissosity associated with extensional shear bands and a cordierite‐bearing schistosity in the orogenic lower and middle crust, respectively. Staurolite relics preserved in the S1 fabric are interpreted as relics of older, higher pressure Barrovian‐type metamorphism. These structural‐metamorphic features are correlated with decompression and heating and interpreted as reflecting a crustal‐scale extensional phase. S1 was folded to form N‐S‐oriented upright antiforms cored by migmatites and locally transposed by steep S2 foliation during a ∼W‐E‐directed shortening (in current coordinates). Andalusite and cordierite overgrew the migmatitic S2 foliation attesting to decreasing pressure associated with vertical extrusion of migmatites in cores of F2 antiforms. New U‐Pb age data from subhorizontally foliated migmatites suggest that the D1 extension started at least before ∼410 Ma. Age data of syn‐D2 granite intrusions and dykes constrain the D2 shortening starting soon after D1 extension and ending at ∼378 Ma. Combined with regional data, cycles of extensional and contractional tectonic regimes can be defined, which also show eastward migration along‐strike of the Altai range. Such extension‐shortening cycles could result from alternating retreating and advancing subduction, which governed the evolution of the Altai accretionary system from the Ordovician until the Carboniferous. Key Points: Crustal extension in the Chinese Altai formed a sub‐horizontal high‐temperature/low‐pressure fabric at Early‐Middle DevonianMiddle Devonian upright folding accounted for shortening of heterogeneously extended, partially molten and stratified crustMultiple shortening‐extension cycles as proxies of alternating retreats and advances of subduction system governed evolution of Altai [ABSTRACT FROM AUTHOR]

For a long time in the practice of geotechnical engineering, soil has been viewed as an inert material, comprising only inorganic phases. However, microorganisms including bacteria, archaea and eukaryotes are ubiquitous in soil and have the capacity and capability to alter bio‐geochemical processes in the local soil environment. The cumulative changes could consequently modify the physical, mechanical, conductive and chemical properties of the bulk soil matrix. In recent years, the topic of bio‐mediated geotechnics has gained momentum in the scientific literature. It involves the manipulation of various bio‐geochemical soil processes to improve soil engineering performance. In particular, the process of microbial‐induced calcium carbonate precipitation (MICP) has received the most attention for its superior performance for soil improvement. The present work aims to shape a comprehensive understanding of recent developments in bio‐mediated geotechnics, with a focus on MICP. Referring to around one hundred studies published over the past five years, this review focuses on popular and alternative MICP processes, innovative raw materials and additives for MICP, emerging tools and testing methodologies for characterizing MICP at multi‐scale, and applications in emerging and/or unconventional geotechnical fields. [ABSTRACT FROM AUTHOR]

Soils are a host to several micro‐organisms which are responsible for various biogeochemical processes prevailing in the geoenvironment. Such processes have been utilized to alter engineering properties of the coarse‐grained soils viz., sands, such as strength, liquefaction potential and permeability. One of such processes, which has been explored by several researchers, is Biogenic Calcite Precipitation (BCP) in the coarse‐grained soils. Though the impact of biogenic calcite (BC) on engineering behaviour of sands has been dealt with in great detail, the mechanism of calcite 'growth' on their surface, which primarily depends on biosorption (i.e. attachment of bacterial cells), has not been investigated and/or discussed in detail. It should be noted that biosorption would strongly depend upon the overall surface characteristics of the sand grains, apart from their chemico‐mineralogical characteristics. Unlike fine‐grained soils, where the bacteria‐soil interaction is being investigated extensively by researchers, the above‐referred studies on sands have been pretermitted, largely. With this in view, an attempt has been made to investigate the mechanisms associated with the interaction of bacterial cells with sand grains and BC substrates, which is a precursor for the biogeochemical processes such as BCP, bioremediation and biological degradation of soils. Highlighting the role of key factors in bacterial cell‐sand interactions, a conceptual model has been proposed for the growth of biogenic calcite around a sand grain. Such a fundamental study, conducted by employing Atomic Force Microscopy and Extended Derjaguin‐Landau‐Verwey‐Overbeek (ExDLVO) theory, provides an insight into the biosorption on sands and BC. [ABSTRACT FROM AUTHOR]

An effective and efficient photovoltaic performance is significantly affected by the interface between different constituents of dye sensitized solar cells (DSSC). A novel dual post treatment of TiCl4 and urea solutions on different layers of TiO2 electrode is addressed and the TiO2 particle morphology, dye‐adsorption amount on the TiO2 electrode and the photovoltaic performance of the DSSC based on those electrodes are characterised in this work. TiCl4 treatment can form more binding site on TiO2 particles and urea treatment structures a thin layer of g‐C3N4 on the surface of TiO2 particles. This strategy can not only effectively increase the dye‐adsorption for light‐harvesting, but also facilitate the electron transfer through inhibiting the charge recombination between TiO2 and electrolyte, and moreover, it provides excess electrons for the photoanodes. The DSSC fabricated from TiO2 electrode processed with urea treatment on the sixth layer exhibited the highest power conversion efficiency of 8.94% with a short current density Jsc of 24.09 mA cm–2, an open circuit voltage Voc of 583 mV and a fill factor of 63.8. [ABSTRACT FROM AUTHOR]

publisher‐imprint‐name Springer volume‐issue‐count 1 issue‐article‐count 0 issue‐toc‐levels 0 issue‐pricelist‐year 2020 issue‐copyright‐holder The Author(s) issue‐copyright‐year 2020 article‐contains‐esm Yes article‐numbering‐style Unnumbered article‐registration‐date‐year 2020 article‐registration‐date‐month 1 article‐registration‐date‐day 6 article‐toc‐levels 0 toc‐levels 0 volume‐type Regular journal‐product ArchiveJournal numbering‐style Unnumbered article‐grants‐type OpenChoice metadata‐grant OpenAccess abstract‐grant OpenAccess bodypdf‐grant OpenAccess bodyhtml‐grant OpenAccess bibliography‐grant OpenAccess esm‐grant OpenAccess online‐first false pdf‐file‐reference BodyRef/PDF/40169_2020_Article_257.pdf pdf‐type Typeset target‐type OnlinePDF issue‐type Regular article‐type OriginalPaper journal‐subject‐primary Medicine & Public Health journal‐subject‐secondary Medicine/Public Health, general journal‐subject‐collection Medicine open‐access true --> Background: The present study sought to identify a panel of DNA markers for noninvasive diagnosis using cell‐free DNA (cfDNA) from urine supernatant or cellular DNA from urine sediments of hematuria patients. A panel of 48 bladder cancer‐specific genes was selected. A next‐generation sequencing‐based assay with a cfDNA barcode‐enabled single‐molecule test was employed. Mutation profiles of blood, urine, and tumor sample from 16 bladder cancer patients were compared. Next, urinary cellular DNA and cfDNA were prospectively collected from 125 patients (92 bladder cancer cases and 33 controls) and analyzed using the 48‐gene panel. The individual gene markers and combinations of markers were validated according to the pathology results. The mean areas under the receiver operating characteristic (ROC) curves (AUCs) obtained with the various modeling approaches were calculated and compared. Results: This pilot study of 16 bladder cancer patients demonstrated that gene mutations in urine supernatant and sediments had better concordance with cancer tissue as compared with plasma. Logistic analyses suggested two powerful combinations of genes for genetic diagnostic modeling: five genes for urine supernatant (TERT, FGFR3, TP53, PIK3CA, and KRAS) and seven genes for urine sediments (TERT, FGFR3, TP53, HRAS, PIK3CA, KRAS, and ERBB2). The accuracy of the five‐gene panel and the seven‐gene panel in the validation cohort yielded AUCs of 0.94 [95% confidence interval (CI) 0.91–0.97] and 0.91 (95% CI 0.86–0.96), respectively. With the addition of age and gender, the diagnostic power of the urine supernatant five‐gene model and the urine sediment seven‐gene model improved as the revised AUCs were 0.9656 (95% CI 0.9368–0.9944) and 0.9587 (95% CI 0.9291–0.9883). Conclusions: cfDNA from urine bears great diagnostic potential. A five‐gene panel for urine supernatant and a seven‐gene panel for urine sediments are promising options for identifying bladder cancer in hematuria patients. [ABSTRACT FROM AUTHOR]

The Claisen condensation reaction is a classical method used for the formation of C−C bonds. Homo‐ and cross‐Claisen condensation reactions are usually carried out using a Ti(IV)‐based reagent at ultra‐low‐temperatures. In this report, intermediate β‐keto acyl imidazoles were synthesised using a sodium imidazolide‐catalysed homo‐ and cross‐condensation reaction of N‐acyl imidazoles performed under mild conditions and subsequently used to prepare a range of β‐keto esters and ketones via alcoholysis or hydrolysis. This method is particularly suitable for the synthesis of isotopically‐labelled acetylacetic ester compounds. N‐acyl imidazole compounds are useful reactants for the Claisen condensation reaction. [ABSTRACT FROM AUTHOR]

During the summer of 2018, one Syringa reticulata plant showing witches' broom and small leaves was observed in Beijing, China. Molecular diagnostic tools and electron microscopic cell observation were used to detect the possible pathogen of this disease. As a result, the phytoplasma in the symptomatic S. reticulata tree was confirmed by amplifying the 16S rRNA gene using the phytoplasma‐specific universal primer pair R16mF2/R16mR1 and observation with transmission electron microscopy. The rp and tuf genes of the phytoplasma were also cloned and sequenced as the 16S rRNA gene. Sequence and phylogenetic analyses of the 16S rRNA, rp and tuf genes indicated that the phytoplasma associated with S. reticulata witches' broom (SrWB) disease belonged to the 16SrV‐B subgroup, and it was closely related to the 16SrV‐B subgroup phytoplasma strain jujube witches' broom, which causes serious disease of jujube fruit trees in China. This study shows the S. reticulata tree as a new host of a phytoplasma belonging to the 16SrV‐B subgroup in China. [ABSTRACT FROM AUTHOR]

BACKGROUND Neonicotinoid insecticides (NIs) have been recently banned in some countries because of increased pest resistance and deleterious risks to non‐target organisms. Recent studies considered all parts of crops as a whole part in plant protection. However, there are few reports focused on the distribution and metabolic trends of NIs on target feeding sites of different pests in apple orchards. RESULTS: The spatial and temporal distribution, absorption, degradation, and metabolism of three NIs, imidacloprid, acetamiprid, and thiamethoxam, on different parts of apple trees were studied under foliar spray and root irrigation treatments. In the spray treatment, the initial average concentration ratios (TCRs) were 31.6% for lower shoots, 23.3% for upper leaves, 23.2% for upper shoots, 21.0% for lower leaves, and 0.5% and 0.4% for upper and lower fruits, respectively. The average half‐lives of the three NIs were 2.9 days for shoots, 7.4 days for leaves, and 10.8 days for fruits. The degradation rate of shoots was 2.5 times that of leaves, and 3.6 times that of fruits. Imidacloprid olefin and N‐methyl acetamiprid were two of the main metabolites. In the root treatment, both roots and soils had high TCRs during the whole sampling period. Only imidacloprid was transmitted to above‐ground parts of the plants, with TCRs of 0.38–50.94%. CONCLUSION: This study found significant differences in spatial and temporal distribution, degradation, metabolism, and trends of NIs on different pest target sites of apple trees. The data obtained may help promote scientific control of target pests and evaluation of safety for non‐target species in orchards. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: The plant bug, Apolygus lucorum Meyer‐Dür, has begun a resurgence and has become a key pest in cotton in northern China, with the wide‐scale adoption of transgenic Bt cotton. We attempted to develop a new approach to the control of this plant bug by identifying and utilizing its sex pheromone. RESULTS: Extracts from A. lucorum adults and nymphs were analyzed using gas chromatography–mass spectrometry (GC–MS) and gas chromatography–electroantennogram detection (GC–EAD) to identify the sex pheromone components. (E)‐4‐Oxo‐2‐hexenal and (E)‐2‐hexenyl butyrate were the major sex pheromone components from females and were also electrophysiology‐active towards male antennae. For males, (E)‐4‐oxo‐2‐hexenal and hexyl butyrate were the major sex pheromone components. These three components, however, were not detected in nymphs. Field tests showed that binary blends of (E)‐4‐oxo‐2‐hexenal and (E)‐2‐hexenyl butyrate at a ratio of 3:2 resulted in trapping the greatest numbers of A. lucorum males. A long‐term dispenser was developed by loading the pheromone components dissolved in sunflower oil into polyethylene vials. Further field evaluation showed that the polyethylene dispensers attracted significantly more bugs even when deployed in the field for 5 weeks. CONCLUSION: We identified the sex pheromone of A. lucorum and developed a type of high‐efficiency and long‐term lure. Our results could expand knowledge of the pheromones of plant bugs, and provide novel technologies to monitor and control this pest. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Bio‐mediated soil improvement involves the usage of microbes to improve soil engineering performance through a series of bio‐geochemical processes. In particular, Microbially Induced Calcite Precipitation (MICP), a ubiquitous bio‐geochemical process that occurs in soil and results in permanent inorganic cementation between soil grains, has received the greatest research focus. While substantial progress has been made to develop MICP as a mainstream soil improvement technique, we still need to: (a) improve our understanding of the fundamental microbial, chemical and flow processes involved; (b) achieve multi‐functionality by coupling engineering performance enhancement with ecological, environmental and carbon footprint benefits; and (c) maintain ecological balance and environmental friendliness, avoid long‐term deterioration and lower the energy demand. [ABSTRACT FROM AUTHOR]

To simplify the control structure and increase the anti-disturbance performance, a non-cascade control method for a permanent magnet synchronous motor drive system is studied, which regulates the speed and current in one loop. The proposed control scheme is a composite control strategy including speed-current single-loop feedback control and feedforward compensation based on disturbance estimation. A feedback controller based on backstepping sliding mode control is proposed to realise speed-current single-loop. Disturbance estimated by a third-order extended state observer is used in feedforward compensation. Rigorous analysis of stability is conducted to validate the convergence of the control scheme. Simulation and experimental results demonstrate that the proposed control scheme achieves a better speed tracking performance and disturbance rejection property over proportional--integral--derivative and sliding mode control. [ABSTRACT FROM AUTHOR]

BACKGROUND Phytophthora capsici is a devastating pathogen for crop. Cellulose synthase 3 (CesA3) is a target for many potential fungicides such as valinamide derivatives. However, the 3‐dimensional structure (3‐DS) of CesA3 in Phytophthora capsici was still unknown. RESULTS: Here CesA3 protein sequence was retrieved from the NCBI protein sequence database We did the 3‐DS structural modeling for CesA3 and used molecular dynamics to optimize the model. The model was further validated by the Ramachandran plot in PROCHECK program. Two series of new valinamide compound were synthesized and tested for its biological activity. The docking data obtained by the model perfectly matched with the biometric data, indicating that the model is valid. Moreover, docking study data revealed the mechanism of action of inhibitors on target enzymes. CONCLUSION: The 3‐DS structural model was analyzed from the perspective of the biocide receptor, the structure of the target protein and the mechanism of action of the compound. It provides a new perspective for the design of new fungicides. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Diamondback moth, Plutella xylostella L., is a very important pest of cruciferous vegetables causing excessive economic losses worldwide. Bioactivities of halo‐, diazo‐, and cyclopropane acetates of P. xylostella sex pheromone have been evaluated using electrophysiology and enzyme inhibition assays. RESULTS: A total of 23 sex pheromone analogs of P. xylostella were designed and synthesized and the result shows that (11Z)‐hexadec‐11‐en‐1‐yl 2,2,2‐trifluoroacetate, (11Z)‐hexadec‐11‐en‐1‐yl 2,2,3,3,3‐pentafluoropropanoate, and (11Z)‐hexadec‐11‐en‐1‐yl trifluoromethanesulfonate elicited potential inhibitory effects at all doses tested in the electrophysiology and enzyme inhibition assays. Interference of locating the sex pheromone source was found strongest when these three analogs were mixed with the sex pheromone at a 10:1 ratio. In addition, field test showed that the rate of mating disruption was over 90% when (11Z)‐hexadec‐11‐en‐1‐yl 2,2,2‐trifluoroacetate or (11Z)‐hexadec‐11‐en‐1‐yl 2,2,3,3,3‐pentafluoropropanoate was mixed with the sex pheromone at a 10:1 ratio. CONCLUSION: Two sex pheromone antagonists were screen out by electrophysiology, enzyme inhibition assays, wind tunnel and field tests. We believe that these antagonists could be used to establish a novel eco‐friendly measure to control P. xylostella and provide evidence for clarifying the specific functions and molecular mechanisms of sex pheromone antagonists. © 2018 Society of Chemical Industry Diamondback moth Plutella xylostella L. is a very important pest of cruciferous vegetables causing excessive economic losses worldwide. Bioactivities of halo‐, diazo‐, and cyclopropane acetates of P. xylostellasex pheromone have been evaluated using electrophysiology and enzyme inhibition assays. [ABSTRACT FROM AUTHOR]

AVO inversion is a seismic exploration methodology used to predict the earth's elastic parameters and thus rocks and fluid properties. It is built up on elastic theory and does not consider the seismic dispersion in real strata. Recent experiments and theory of rock physics have shown that in hydrocarbon-bearing rocks, especially in gas-bearing ones, the change of seismic velocity with frequency may be pretty remarkable for fluid flow in pore space. Some scholars proposed methods about seismic dispersion, such as frequency-dependent AVO inversion, to forecast oil and gas reservoirs underground. In this paper, we demonstrate an improved scheme of frequency-dependent AVO inversion, which is based on conventional Smith-Gidlow's AVO equation, to extract seismic dispersion and predict the hydrocarbon underground. A simple model with gas-bearing reservoir is devised to validate the inversion scheme, and further analysis indicates that our scheme is more accurate and reasonable than the previous scheme. Our new scheme applied to the tight gas reservoirs in Fenggu area of western Sichuan depression of China finds that regions with high dispersion gradients correlate well with regions with prolific gas. Analysis and case studies show that our scheme of frequency-dependent AVO inversion is an efficient approach to predict gas reservoirs underground. [ABSTRACT FROM AUTHOR]

BACKGROUND Treated soil is the second most prevalent application technique for all registered pesticides in China. Some developing countries also adopt this method. However, the safety of this scenario has not been reported in the literature. Experiments were therefore conducted to assess exposure using standard whole-body dosimetry and air sampling methodologies. RESULTS Dermal deposition was the main route of exposure in this scenario. The total dermal unit exposure ( UE) of operators to clothianidin-treated soil was 51.7 mg kg−1 AI handled ( SD = 20.59, n = 16), and hands accounted for 36%. Inhalation UE was 0.04 mg kg−1 AI handled ( SD = 0.02, n = 4), negligible compared with dermal exposure. Using an NOAEL (no observed adverse effect level) of 10 mg kg−1 day−1, the margin of exposure was 773, i.e. greater than 100. CONCLUSION For the first time, the scenario of treated soil exposure was assessed and was found to pose less risk than conventional pesticide application. These results can be used as a reference in pesticide management. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

To reduce energy consumption and protect the environment, a type of hollow shale block with 29 rows of holes was designed and produced. This paper investigated the thermal properties of hollow shale blocks and walls. First, the guarding heat-box method was used to obtain the heat transfer coefficient of the hollow shale block walls. The experimental heat transfer coefficient is 0.726 W/m2·K, which would save energy compared to traditional wall materials. Then, the theoretical value of the heat transfer coefficient was calculated to be 0.546 W/m2·K. Furthermore, the one-dimensional steady heat conduction process for the block and walls was simulated using the finite element analysis software ANSYS. The predicted heat transfer coefficient for the walls was 0.671 W/m2·K, which was in good agreement with the test results. With the outstanding self-insulation properties, this type of hollow shale block could be used as a wall material without any additional insulation measures in masonry structures. [ABSTRACT FROM AUTHOR]

In northern China, due to the large-scale adoption of transgenic Bacillus thuringiensis Berliner (Bt) cotton, the number of Adelphocoris lineolatus ( Goeze) ( Hemiptera: Miridae) has increased quickly, causing significant loss in cotton and alfalfa production. One of the environmentally safe strategies without use of pesticides is the application of insect pheromone for mating disruption. In our study, we aim to identify the active components in sexually mature virgin female A. lineolatus, and activity and optimal ratio of these components. By using gas chromatography-mass spectrometry ( GC- MS) and gas chromatography-electroantennographic detection ( GC- EAD), we identified three active compounds: hexyl butyrate ( HB), ( E)-2-hexenyl butyrate (E2 HB), and ( E)-4-oxo-2-hexenal (4- OHE). We examined the release rate of septum and tube dispensers in a wind tunnel. In a field experiment, deletion of 4- OHE or E2 HB resulted in significant suppression of male trap catches, indicating that E2 HB or 4- OHE may be the active pheromone components. Traps baited with a blend of 4- OHE and E2 HB at 2:5, 3:4, and 4:3 caught significantly more males, suggesting that the optimal ratio of 4- OHE and E2 HB could be in the range of 1:1 to 1:2. The addition of a large amount of HB could strongly reduce the attractive activity of both virgin females and artificial lures. We also compared the attractiveness of septum lures and tube lures in field experiments. The septum lures attracted males in the first 3 days. The tube lures caught more males after 3 days and the attractive effects existed up to 5 weeks, suggesting them as a tool for long-term monitoring and control of plant bugs. [ABSTRACT FROM AUTHOR]

BACKGROUND With the objective of finding novel valuable herbicidal candidates, a series of novel 4-(1 H-pyrazol-1-yl)-6-(alkynyloxy)-pyrimidine derivatives were synthesised and their herbicide activities were evaluated in vivo. RESULTS The results showed that many target compounds expressed bleaching activities. Among these, compound 5 h showed the best bleaching activity to gramineous weeds, being able to produce the highest inhibition of chlorophyll level in seedlings of Pennisetum alopecuroides L. ( IC50 = 3.48 mg L−1). Moreover, compound 5 h expressed good selective toxicity between gramineous P. alopecuroides L. and broadleaf plant Brassica campestris L. CONCLUSIONS The present work demonstrates that pyrimidine derivatives containing pyrazole can be used as potential lead compounds for developing novel pigment biosynthesis inhibitors. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND To date, no research has been conducted to establish exposure levels for occupational pesticide operators under typical use scenarios in China. Through surrogate skin techniques (the whole-body method), the authors monitored dermal and inhalation exposure of pesticide applicators in China. In addition, the exposure of pesticide mixers was analysed. RESULTS The total dermal exposure of inexperienced and experienced applicators was respectively 4037 and 536 mg kg−1 of active ingredient ( AI) handled for application to maize that was <80 cm in height. The exposure level was highest on hands; the closer to the hands, the lower arms and the upper legs, the higher the exposure. The unit exposure of mixers differed according to the formulation; exposure to emulsifiable concentrate ( EC) and oil-in-water emulsion ( EW) was greater than exposure to wettable powder ( WP) or wettable dispersible granules ( WG). The unit exposure of mixers via inhalation was significantly greater than that of applicators when chlorpyrifos (48% EC) was used ( P < 0.0001). CONCLUSIONS The main objectives of this study were to provide an indication of the realistic exposure risk of mixers and applicators, and to contribute useful information for risk mitigation and management and epidemiological studies in China. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Atrazine is a long-lasting herbicide that has been shown to affect hormone levels in amphibians. Using the C-13 labeled atrazine to detect its residue is effective and essential. This study presents three steps for the synthesis of [13C3]atrazine, which starts from [13C]urea, and results in the incorporation of C-13 atoms at the 1, 3 and 5 positions of the S-triazine ring of atrazine. The method prepares the product in an overall yield of 57.6% and chemical purity of 98.6%, for use as an internal standard. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In the title compound, C8H9ClN2O, the dihedral angle between the benzene ring and the methyl-amide substituent is 68.39 (11)°. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming layers parallel to the ab plane.

In the title compound, C19H18F3NO4, which was designed and synthesized as a dual-site inhibitor of insect AChE (acetyl-cholinesterase), the dihedral angle between the methyl-carbamate group and the benzene ring is 72.47 (6)°. In the crystal, inversion dimers are linked by pairs of N-H⋯O hydrogen bonds.

There are two mol-ecules in the asymmetric unit of the title compound, C(12)H(11)BrN(4)O. The dihedral angles between the pyrazole and pyrimidine rings are 1.28 (17) and 1.56 (17)° in the two mol-ecules. In one of the mol-ecules, the but-3-yn-yloxy side chain is disordered over two sets of sites in a 0.714 (8):0.286 (8) ratio.

In the title compound, C(11)H(9)IN(4)O, the dihedral angle between the pyrazole and pyrimidine rings is 6.30 (16)°. In the crystal, weak C-H⋯O inter-actions link the mol-ecules.

The complete mol-ecule of the the title compound, C(14)H(10)F(6)N(6), is generated by crystallographic twofold symmetry, with two C atoms lying on the roatation axis. The dihedral angle between the central and peripheral rings is 25.97 (8)°.