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The programmable switch offers a limited capacity of packet header vector (PHV) words that store packet header fields and metadata fields defined by network functions. However, existing switch compilers employ inefficient strategies of encoding fields on PHV words. Their encoding wastes scarce PHV words and may result in failures when deploying network functions. In this paper, we propose Melody, a new framework that reuses PHV words for as many fields as possible to achieve resource-efficient PHV encoding. Melody offers a field analyzer and an optimization framework. The analyzer identifies which fields can reuse PHV words while preserving the original packet processing logic. The framework integrates analysis results into its encoding to offer the resource-optimal decisions. Also, to achieve timeliness at runtime, it provides a Greedy-based heuristic, which quickly solves PHV encoding and returns near-optimal results. We evaluate Melody with production-scale network functions. Our results show that Melody reduces the consumption of PHV words by up to 85%.

In modern data center networks (DCNs), network-stack processing denotes a large portion of the end-to-end latency of TCP flows. So profiling network-stack latency anomalies has been considered as a crucial part in DCN performance diagnosis and troubleshooting. In particular, such profiling requires full coverage (i.e., profiling every TCP packet) and low overhead (i.e., profiling should avoid high CPU consumption in end-hosts). However, existing solutions rely on system calls or tracepoints in end-hosts to implement network-stack latency profiling, leading to either low coverage or high overhead. We propose Torp, a framework that offers full-coverage and low-overhead profiling of network-stack latency. Our key idea is to offload as much of the profiling from costly system calls or tracepoints to the Torp agent built on eBPF modules, and further to include a Torp handler on the ToR switch to accelerate the remaining profiling operations. Torp efficiently coordinates the ToR switch and the Torp agent on end-hosts to jointly execute the entire latency profiling task. We have implemented Torp on $32\times 100$ Gbps Tofino switches. Testbed experiments indicate that Torp achieves full coverage and orders of magnitude lower host-side overhead compared to other solutions.

Network administrators usually realize network functions in data plane programs. They employ the network-wide program deployment that decomposes input programs into match-action tables (MATs) while deploying each MAT on a specific switch. Since MATs may be deployed on different switches, existing solutions propose the inter-switch coordination that uses the per-packet header space to deliver crucial packet processing information among switches. However, such coordination incurs non-trivial per-packet byte overhead, leading to end-to-end performance degradation. We propose Hermes, a framework that aims to minimize the per-packet byte overhead. The key idea is to formulate network-wide program deployment as a mixed-integer programming (MIP) problem with the objective of minimizing the per-packet byte overhead. Also, Hermes offers a greedy-based heuristic that solves the problem in a near-optimal and timely manner. We have implemented Hermes on Tofino switches. Compared to existing frameworks, Hermes decreases the per-packet byte overhead by 156bytes while preserving end-to-end performance in terms of flow completion time and goodput.

To date, security researchers evaluate their solutions of mitigating distributed denial-of-service (DDoS) attacks via kernel-based or kernel-bypassing testing tools. However, kernel-based tools exhibit poor scalability in attack traffic generation while kernel-bypassing tools incur unacceptable monetary cost. We propose Excalibur, a scalable and low-cost testing framework for evaluating DDoS defense solutions. The key idea is to leverage the emerging programmable switch to empower testing tasks with Tbps-level scalability and low cost. Specifically, Excalibur offers intent-based primitives to enable academic researchers to customize testing tasks on demand. Moreover, in view of switch resource limitations, Excalibur coordinates both a server and a programmable switch to jointly perform testing tasks. It realizes flexible attack traffic generation, which requires a large number of resources, in the server while using the switch to increase the sending rate of attack traffic to Tbps-level. We have implemented Excalibur on a $64\times 100$ Gbps Tofino switch. Our experiments on a $64\times 100$ Gbps Tofino switch show that Excalibur achieves orders-of-magnitude higher scalability and lower cost than existing tools.

With the continuous integration of information technology and operation technology, the Industrial Internet of Things (IIoT) is gradually changing from closed to open. Operators can configure, monitor, or control the industrial production process remotely via Internet, which brings security threats to IIoTs. Since the IIoT focuses on the availability of industrial production, it is unfeasible to study security issues directly on the industrial field. Thus, constructing an IIoT cyber range to reproduce industrial scenarios for offensive and defensive confrontation research is necessary. However, the traditional IIoT cyber range relies on physical industrial field devices that are not reproducible and hard to recover from cyber-attacks. To solve these problems, in this article, we propose a framework for a digital twin-based cyber range and a digital twin construction method with multiple models. Cyber ranges with digital twins are more flexible and convenient. Based on the proposed method, an industrial scenario is reproduced using machine learning algorithms to predict temperature changes from different perspectives. The experimental result shows the ability of digital twins to construct an IIoT cyber range to reproduce production processes and replace field devices.

Recent efforts in network measurement place measurement tasks on programmable switches to measure high-speed traffic. These tasks extract flow data, i.e., events, from packets and send events to the control plane. However, the tasks may generate massive events in a short time. In this context, the links transferring events to the control plane and the control plane servers that handle events may be overloaded, i.e., control plane overload. None of existing solutions can eliminate control plane overload. In this paper, we propose MTP, a framework that eliminates control plane overload via careful measurement task placement. Our key idea is to allocate enough resources for each task during task placement to avoid control plane overload at runtime. For each task, MTP estimates its maximum possible rate of sending events to the control plane. Then its optimization framework addresses the resource restrictions of both switches and the control plane. The experiments on Tofino switches indicate that MTP outperforms existing solutions with higher accuracy in several use cases.

The green peach aphid, Myzus persicae, is the most serious agricultural pest worldwide, and its control relies mainly on insecticides such as neonicotinoids, due to their broad spectrum. Nicotinic acetylcholine receptors (nAChRs) are the target genes of neonicotinoids, and better knowledge of their toxicological mechanisms is crucial for developing new specific neonicotinoids, especially for non-model insects. In this study, we successfully cloned four nAChR α subunits in M. persicae and coexpressed them with Rattus norvegicus β2 in the Xenopus oocyte system. Screening results showed that Mpα1 and Mpα8 were narrowly tuned to sulfoxaflor and thiamethoxam, with EC50 values of 1.117 × 10−4 M and 9.681 × 10−5 M, respectively. Molecular modeling and docking results showed that a combination of positive (Lys) and aromatic (Trp) residues or positive (Lys) and polar (Ser) residues located at the interface of the corresponding α and β subunits of nAChR in Mpα1/ratβ2 or Mpα8/ratβ2 was the main contributor to ligand binding. Therefore, three residues (W143A, K144A and F260A) of Mpα1 and four residues (K63A, K134A, S146A and V290A) of Mpα8 were mutated to validate their contributions to the binding affinity of the corresponding ligand. In Mpα1, W143A resulted in a significantly lower sensitivity to sulfoxaflor than the other three mutations, and in Mpα8, S146A significantly reduced the response to thiamethoxam, suggesting crucial roles of these predicted hydrogen bonding sites in channel activation. These results provide evidence of the neonicotinoid toxicological mechanism in M. persicae and reveal new gene targets and binding sites for future pesticide design.

Oxidizing ClO−and IO4−exist widely in environment and are closely related to the health of organisms. Accordingly, fast, sensitive, and direct detection of the two species is significant. Using IFE in UCNPs @PAA and Fe(II)-phenanthroline system, an elegant ratiometric fluorescent nanosensor, without noble metal nanoparticle, was designed for the detection of ClO−and IO4−. Fe(II)-phenanthroline complex is used as fluorescent absorber, which can quench green light of UCNPs with gradually varied extent depending on the concentration of Fe(II). The linear zone extends to 800 and 120 μmol/L while the detection limit is 1.30 and 0.58 μmol/L for NaClO and NaIO4, respectively. Finally, the nanosensor was successfully applied to detect NaClO and NaIO4spiked in milk, spring water, and tap water with good recoveries.

Programmable switches empower stateful packet processing, in which incoming packets continuously update states in the data plane, while applications in the control plane read and write states. However, since the data plane and control plane are separated, a consistent view of states in both planes is required for stateful packet processing. Existing approaches suffer from either high latency or low accuracy. In this paper, we propose ApproSync, a framework that offers approximate state synchronization with low latency and high accuracy. To achieve low latency, ApproSync directly transfers states between switch ASICs and the control plane by bypassing switch operating systems. To achieve high accuracy, ApproSync utilizes the resources in the switch ASIC to realize rate control in state synchronization, such that it avoids potential state loss. It also bounds the divergence between the states in the data plane and that in the control plane under limited link capacity. We prototype ApproSync on Barefoot Tofino switches. The experimental results indicate that compared to existing approaches, ApproSync achieves order-of-magnitude latency reduction while maintaining high accuracy of state synchronization. Also, our experiments demonstrate that ApproSync provides significant latency benefits to existing network management applications and well preserves high application-level accuracy.

Distributed denial-of-service (DDoS) attacks have long been the most severe and destructive attack on modern networks. Some solutions place several middleboxes that run security-oriented network functions (SNFs) in the network to defend against DDoS attacks. However, middleboxes are proprietary and fixed-function, making them costly and inflexible when handling attack dynamics. Another class of solutions exploits the capability of software-defined networking (SDN) and network function virtualization (NFV) to run virtualized SNFs on commodity servers. This reduces the cost of DDoS attack mitigation while enabling high flexibility by dynamically removing or adding SNF instances. However, this class of solutions sacrifices packet processing performance and incurs non-trivial end-to-end latency, which is unacceptable for many latency-sensitive internet services. Recently, the emergence of programmable switches brings a promising alternative solution: arbitrary SNFs can be directly performed in line-rate ASIC pipelines of programmable switches, enabling low-cost, flexible, and high-performance DDoS attack mitigation. In this article, we present an illustrative survey of recent solutions that leverage programmable switches to provide DDoS attack mitigation. Our survey can help understand how to make full use of the benefits of programmable switches to defend against DDoS attacks.

Novel double-network (DN) ion-conducting hydrogel (ICH) based on a poly(ionic liquid)/MXene/poly(vinyl alcohol) system (named PMP DN ICH) was synthesized using freeze–thawing and ionizing radiation technology.The PMP DN ICH possesses a multiple cross-linking mechanism and exhibits outstanding ionic conductivity (63.89 mS cm−1), excellent temperature resistance (−60–80 °C) and decent mechanical performance.The well-designed PMP DN ICH shows considerable potential in wearable sensing, energy storage, and energy harvesting.

Wheat root diseases can seriously reduce yields and quality of wheat. 1,2,4-Triazole benzoyl arylamine derivatives previously showed good activities against some wheat root fungal pathogens. To further systematically disclose the structure–activity relationship, a series of benzoyl arylamines were designed and prepared. Their structures were characterized and fungicidal activities against Gaeumannomyces graminisvar. triticiand Fusarium graminearumwere evaluated. The results indicated that the structure of the N-heterocyclic group and the substituted group and their position on the benzamide scaffold had an important influence on the activities, as predicted. Finally, compound 18fwas found to show excellent activities against G. graminisvar. tritici, F. graminearum, Fusarium culmorum, Fusarium pseudograminearum, and Fusarium moniliformewith half-maximum effective concentrations of 0.002, 0.093, 0.011, 0.881, and 0.287 μg/mL, respectively. These results proposed that compound 18fdeserved serious consideration as a novel fungicide candidate for the control of wheat root diseases.

Ulcerative colitis(UC) is a chronic inflammatory bowel disease caused by many factors including colonic inflammation and microbiota dysbiosis. Previous studies have indicated that celastrol(CSR) has strong anti-inflammatory and immune-inhibitory effects. Here, we investigated the effects of CSR on colonic inflammation and mucosal immunity in an experimental colitis model, and addressed the mechanism by which CSR exerts the protective effects. We characterized the therapeutic effects and the potential mechanism of CSR on treating UC using histological staining, intestinal permeability assay, cytokine assay, flow cytometry, fecal microbiota transplantation (FMT), 16S rRNA sequencing, untargeted metabolomics, and cell differentiation. CSR administration significantly ameliorated the dextran sodium sulfate (DSS)-induced colitis in mice, which was evidenced by the recovered body weight and colon length as well as the decreased disease activity index (DAI) score and intestinal permeability. Meanwhile, CSR down-regulated the production of pro-inflammatory cytokines and up-regulated the amount of anti-inflammatory mediators at both mRNA and protein levels, and improved the balances of Treg/Th1 and Treg/Th17 to maintain the colonic immune homeostasis. Notably, all the therapeutic effects were exerted in a gut microbiota-dependent manner. Furthermore, CSR treatment increased the gut microbiota diversity and changed the compositions of the gut microbiota and metabolites, which is probably associated with the gut microbiota-mediated protective effects. In conclusion, this study provides the strong evidence that CSR may be a promising therapeutic drug for UC.

The Minamata Convention on Mercury calls for Hg control actions to protect the environment and human beings from the adverse impacts of Hg pollution. It aims at the entire life cycle of Hg. Existing studies on the Hg cycle in the global environmental–economic system have characterized the emission-to-impact pathway of Hg pollution. That is, Hg emissions/releases from the economic system can have adverse impacts on human health and ecosystems. However, current modeling of the Hg cycle is not fully looped. It ignores the feedback of Hg-related environmental impacts (including human health impacts and ecosystem impacts) to the economic system. This would impede the development of more comprehensive Hg control actions. By synthesizing recent information on Hg cycle modeling, this critical review found that Hg-related environmental impacts would have feedbacks to the economic system via the labor force and biodiversity loss. However, the interactions between Hg-related activities in the environmental and economic systems are not completely clear. The cascading effects of Hg-related environmental impacts to the economic system throughout global supply chains have not been revealed. Here, we emphasize the knowledge gaps and propose possible approaches for looping the Hg cycle in global environmental–economic system modeling. This progress is crucial for formulating more dynamic and flexible Hg control measures. It provides new perspectives for the implementation of the Minamata Convention on Mercury.

India is among the largest emitters of atmospheric mercury (Hg) in the world. India’s production activities have associated Hg emissions which can be attributed to final demands (e.g., purchases by households, governments, and private investments) of nations driving upstream production from the demand perspective, or primary inputs (e.g., labor and capital supply) of nations enabling downstream production from the supply perspective. This study identifies key nations and sectors that directly and indirectly drove India’s Hg emissions from both the demand and supply perspectives during 2004–2014. While domestic final demand was the dominant driver from the demand perspective (driving about 80–85% of the total), USA, China, and UAE are important foreign drivers. Similarly, from the supply perspective, domestic primary inputs were the dominant drivers. However, the share of foreign inputs enabling Hg emissions increased from 16 to 23% during the decade. Saudi Arabia, Indonesia, Australia, and China are the top foreign supply-side drivers. The Construction sector is an important demand-side driver, whereas fossil fuel sectors are important supply-side drivers. These findings can guide global and national policies for demand- and supply-side management of Hg emissions in India and assist in the successful implementation of the Minamata Convention on Mercury.

The methyl-CpG-binding domain 2 (MBD2) interprets DNA methylome-encoded information through binding to the methylated CpG DNA, by which it regulates target gene expression at the transcriptional level. Although derailed DNA methylation has long been recognized to trigger or promote autoimmune responses in type 1 diabetes (T1D), the exact role of MBD2 in T1D pathogenesis, however, remains poorly defined. Herein, we generated an Mbd2knockout model in the NOD background and found that Mbd2deficiency exacerbated the development of spontaneous T1D in NOD mice. Adoptive transfer of Mbd2−/−CD4 T cells into NOD.scidmice further confirmed the observation. Mechanistically, Th1 stimulation rendered the Stat1promoter to undergo a DNA methylation turnover featured by the changes of DNA methylation levels or patterns along with the induction of MBD2 expression, which then bound to the methylated CpG DNA within the Stat1promoter, by which MBD2 maintains the homeostasis of Th1 program to prevent autoimmunity. As a result, ectopic MBD2 expression alleviated CD4 T cell diabetogenicity following their adoptive transfer into NOD.scidmice. Collectively, our data suggest that MBD2 could be a viable target to develop epigenetic-based therapeutics against T1D in clinical settings.

An asymmetric reductive amination of aryl N‐heteroaryl ketones with Benzyl Amines has been realized via one‐pot two‐step process, using p‐toluenesulfonic acid and chiral iridium complexes as catalysts, a mixture of formic acid/triethylamine as a reductant. Twenty‐three examples of chiral aryl N‐heteroaryl methylamines were obtained with good yields and up to 99% ee. Various chiral aryl N‐heteroaryl methylamineswere prepared with good yields and up to 99% enantioselectivity via one‐pot stepwise ketimine formation/asymmetric transfer hydrogenation of aryl N‐heteroaryl ketones and benzyl amines.

The aspartate to alanine transaminase (AST/ALT) ratio indicates oxidative stress and inflammatory reactions related to the occurrence of diabetic retinopathy (DR). Currently, there are no reports on the correlation between AST/ALT ratio and DR. Hence, this study aimed to explore the relationship between AST/ALT ratio and DR. This cross-sectional study utilized data from the Metabolic Management Center of the First People’s Hospital in City. In total, 1365 patients with type 2 diabetes mellitus (T2DM) participated in the study, including 244 patients with DR and 1121 patients without DR. We collected the results of fundus photography, liver function, and other research data and grouped them according to tertiles of AST/ALT ratios. DR prevalence was the highest in the group with the highest AST/ALT ratio (22.12%, P = .004). Both univariate (OR = 2.25, 95% CI: 1.51–3.34, P < .001) and multivariable logistic regression analyses (adjusted for confounding factors) showed that the risk of DR increased by 36% when the AST/ALT ratio increased by 1 standard deviation (SD) (OR = 1.36, 95% CI: 1.16–1.59, P < .001), and 29.3% was mediated by the duration of diabetes. A sensitivity analysis confirmed the stability of the results. This study showed that an increase in AST/ALT ratio is an independent risk factor for DR.

Given the growing interest in eco-friendly lighting solutions, the use of high-quality phosphors has become integral to the advancement of all-solid white light-emitting diodes (WLEDs). One novel phosphor, La3Ga5SiO14:Mn4+(LGS), has been successfully synthesized via a high-temperature solid-state reaction. The crystal structure of LGS is classified as belonging to the trigonal phase, with a space group P321. The excitation spectrum exhibits a wide peak within the wavelength range of 280–440 nm. It emits a highly intense red light, with a peak emission occurring at 715 nm within the spectral range of 670–740 nm is attributed to the transition of Mn4+from 4A2gto 4T2g. LGS:Mn4+demonstrates a favorable quantum efficiency of 16% when doped with a concentration of 0.25 mol% Mn. The decay curve of LGS:Mn4+exhibits a pattern of decreasing lifetime as the dopant concentration increases. Additionally, the LGS:Mn4+products demonstrate a CIE chromaticity of (0.688, 0.2644), which is located within the deep red light region. All the aforementioned findings support the potential application of LGS:Mn4+specimens in WLEDs, thereby contributing to the progress of environmentally friendly and energy-efficient lighting.

A fluorescent chiral sensor is proposed based on the inner filter effect (IFE) of chiral Au nanoparticles (AuNPs) on MoS2quantum dots (MoS2QDs), which can be used for the discrimination of the isomers of tyrosine (Tyr). l-Tyrosine (l-Tyr) can induce obvious agglomeration of the chiral AuNPs, leading to an attenuated IFE of the chiral AuNPs and greatly restored fluorescence of the MoS2QDs, and thus the enantioselective recognition of the Tyr isomers can be achieved. Also, l-Tyr but not d-Tyr induced agglomeration of the chiral AuNPs is confirmed by the larger association constant between l-Tyr and the chiral sensor.

Background: Since December 2019, novel coronavirus (SARS-CoV-2)-induced pneumonia (COVID-19) occurred in Wuhan, and rapidly spread throughout China. COVID-19 patients demonstrated significantly different outcomes in clinic. We aimed to figure out whether obesity is a risk factor influencing the progression and prognosis of COVID-19. Methods: 95 patients with COVID-19 were divided into obesity group and non-obesity group according to their body mass index (BMI). The demographic data, clinical characteristics, laboratory examination, and chest computed tomography (CT) were collected, analyzed and compared between two groups. Results: Our data showed that COVID-19 patients with obesity had more underlying diseases and higher mortality rate compared to those without obesity. Furthermore, patients with obesity also demonstrated more severe pathological change in lung and higher blood lymphocytes, triglycerides, IL-6, CRP, cystatin C, alanine aminotransferase (ALT), erythrocyte sedimentation rate (ESR), which may greatly influence disease progression and poor prognosis of COVID-19. Conclusions: It suggest that obesity contributes to clinical manifestations and may influence the progression and prognosis of COVID-19 and it is considered as a potential risk factor of the prognosis of COVID-19. Special medical care and appropriate intervention should be performed in obesity patients with COVID-19 during hospitalization and later clinical follow-up, especially for those with additional other comorbidities.

Over 100 nations signed the Minamata Convention on Mercuryto control the adverse effects of mercury (Hg) emissions on human beings. A spatially explicit analysis is needed to identify the specific sources and distribution of Hg-related health impacts. This study maps China’s Hg-related health impacts and global supply chain drivers (i.e., global final consumers and primary suppliers) at a high spatial resolution. Here we show significant spatial heterogeneity in hotspots of China’s Hg-related health impacts. Approximately 1% of the land area holds only 40% of the Chinese population but nearly 70% of the fatal heart attack deaths in China. Moreover, approximately 3% of the land area holds nearly 60% of the population but 70% of the intelligence quotient (IQ) decrements. The distribution of hotspots of China’s Hg-related health impacts and global supply chain drivers are influenced by various factors including population, economy, transportation, resources, and dietary intake habits. These spatially explicit hotspots can support more effective policies in various stages of the global supply chains and more effective international cooperation to reduce Hg-related health impacts. This can facilitate the successful implementation of the Minamata Convention on Mercury.

Hyperglycemia is the consequence of blood glucose dysregulation and a driving force of diabetic complications including retinopathy, nephropathy and cardiovascular diseases. The serum and glucocorticoid inducible kinase-1 (SGK1) has been suggested in the modulation of various pathophysiological activities. However, the role of SGK1 in blood glucose homeostasis remains less appreciated. In this review, we intend to summarize the function of SGK1 in glucose level regulation and to examine the evidence supporting the therapeutic potential of SGK1 inhibitors in hyperglycemia. Ample evidence points to the controversial roles of SGK1 in pancreatic insulin secretion and peripheral insulin sensitivity, which reflects the complex interplay between SGK1 activation and blood glucose fluctuation. Furthermore, SGK1 is engaged in glucose absorption and excretion in intestine and kidney and participates in the progression of hyperglycemia-induced secondary organ damage. As a net effect, blockage of SGK1 activation via either pharmacological inhibition or genetic manipulation seems to be helpful in glucose control at varying diabetic stages.

A method for the efficient synthesis of chiral cycloallylalcohols has been developed, achieving excellent yields and enantioselectivities (>99% conversion, turnover number of ≤50 000, and >99% ee). This approach accommodates a variety of cycloalkenones with different aryl substituents and is tolerant of a broad range of functional groups. The synthetic utility of this method has been demonstrated through gram-scale synthesis and subsequent transformations into diverse enantioenriched oxygen-containing compounds.

A novel full atom-economic process for the transformation of alkynes into chiral alcohols by TfOH-catalyzed hydration coupled with Ru-catalyzed tandem asymmetric hydrogenation in TFE under simple conditions has been developed. A range of chiral alcohols was obtained with broad functional group tolerance, good yields, and excellent stereoselectivities.

The CRAFITY score can predict survival and radiological response to systemic front-line treatment in patient with hepatocellular carcinoma (HCC).

A highly enantioselective transfer hydrogenation of non-ortho-substituted aryl N-heteroaryl ketones, using readily available chiral diamine-derived iridium complex (S,S)-1fas a catalyst and sodium formate as a hydrogen source in a mixture of H2O/i-PrOH (v/v = 1:1) under ambient conditions, is described. The chiral aryl N-heteroaryl methanols were obtained with up to 98.2% ee by introducing an N-oxide as a removable ortho-substituent. In contrast, no more than 15.1% ee was observed in the absence of an N-oxide moiety. Furthermore, the practical utility of this protocol was also demonstrated by gram-scale asymmetric synthesis of bepotastine besilate in 51% total yield and 99.9% ee.

•Transmission centers of embodied forage-livestock conflicts (FLCs) are revealed.•Spatial distribution of transmission centers changed during 2005–2015.•Structural changes in supply chains influence the dynamics of transmission centers.•Productivity improvement of transmission centers can help mitigate the FLCs.

The meadow moth, Loxostege sticticalis, is a typical agricultural pest that uses sex pheromones to mediate mating behavior; however, the mechanism underlying the selectivity of its pheromone-binding proteins (PBPs) remains unknown. In this study, LstiPBP1 and LstiPBP3 were cloned, expressed, and purified, and the fluorescence binding assay showed that LstiPBP1 binds to the major sex pheromone component, E-11-tetradecenol (E11-14:OH), with high affinity; moreover, E11-14:OH could evoke a significant antennal electrophysiological response and attract L. sticticalismales. After LstiPBP1 was silenced, both the antennal response and attractiveness of E11-14:OH decreased significantly. Molecular docking predicted that a hydrogen bonding site, Leu37, played key role in the binding of LstiPBP1 to E11-14:OH. After Leu37 was mutated, the E11-14:OH-binding affinity decreased drastically. These results suggest that LstiPBP1 participates in E11-14:OH recognition and could be used as a target gene to disturb the mating behavior of L. sticticalisand develop new odorants for pest control.

Herein we report that the reactions of potassium ferrate (VI) with a number of reductants can produce strong chemiluminescence (CL) in acidic aqueous solution. The CL Spectra were registered and compared with the classical KMnO4and NaClO-H2O2CL systems. The characteristic emission peaks at 1268 and 1050 nm were observed, which are consistent to the spectrum obtained from the NaClO–H2O2system. Additional emission bands at 680 nm further confirmed the formation of singlet oxygen dimers. The high CL intensity and the chemically green nature of K2FeO4, prompt us to further develop it as a novel CL reagent. Sensitive response and wide calibration ranges were obtained for dopamine, ascorbic acid, and ethanol. The linear range for the determination of three analytes were 50 nM to 50 μM for dopamine (LOD: 20 nM), 5.0 μM to 1.0 mM for ascorbic acid (LOD: 2.21 μM), and 0.5 μM to 1.0 mM for ethanol (LOD: 0.30 μM). Thus, K2FeO4has a great potential for the postcolumn detection of those UV featureless compounds.

A lignin amphoteric surfactant and betaine could enhance the enzymatic hydrolysis of lignocellulose and recover cellulase. The effects of lignosulfonate quaternary ammonium salt (SLQA) and dodecyl dimethyl betaine (BS12) on enzymatic hydrolysis digestibility, ethanol yield, yeast cell viability, and other properties of high-solid enzymatic hydrolysis and fermentation of a corncob residue were studied in this research. The results suggested that SLQA and 1 g/L BS12 effectively improved the ethanol yield through enhancing enzymatic hydrolysis. SLQA had no significant effect on the yeast cell membrane and glucose fermentation. However, 5 g/L BS12 reduced the ethanol yield as a result of the fact that 5 g/L BS12 damaged the yeast cell membrane and inhibited the conversion of glucose to ethanol. Our research also suggested that 1 g/L BS12 enhanced the ethanol yield of corncob residue fermentation, which was attributed to the fact that lignin in the corncob adsorbed BS12 and decreased its concentration in solution to a safe level for the yeast.

Nanodots are attractive stimuli-responsive luminescence materials for anti-counterfeiting and information encryption. However, their applications are limited by low water solubility and single-mode information identification by naked eyes under UV light illumination. Herein, we report one type of new nanodots, main-chain imidazolium-based ionic polymer dots (IPDs). There is no edge effect in IPDs, and the ionic groups are homogenously distributed in the entire dot. IPDs exhibit high water solubility, good stability, narrow size distribution, low toxicity, and exceptional optical performance without additional modification. Written information using aqueous IPD solution is invisible in natural light, but can be recognized by a portable UV lamp. Moreover, they can be further encrypted and decrypted using easily available and nontoxic sodium carbonate and acetic acid, respectively. The encrypted information is invisible in natural light and/or UV light. This study provides a new prospect for high-level data recording and security protection by using water-soluble IPDs as invisible security ink.

NaGdF4: A (A = Eu, Tb)@NaGdF4: Yb, Tm@NaGdF4: Yb, Nd core–shell–shell is designed to achieve 808 nm excited upconversion emission tuning. On the basis of the above core–shell–shell nanostructure, intense upconversion emission has been realized for activators without long-lived intermediate states (Eu3+, Tb3+) through Gd3+-mediated energy migration under 808 nm irradiation, enriching the emission colors. The spatial separation, where sensitizer (Nd3+), accumulator (Tm3+), and activator (Eu3+, Tb3+) are doped into separated layers, effectively suppresses nonradiative decays so that the doping concentration of Nd3+can reach to 40%, vastly enhancing the luminescence intensity. Notably, when Gd3+ions are replaced by Nd3+or inert Y3+in NaGdF4: Yb, Nd outer shell, without Gd3+-mediated energy migration, the deleterious energy transfer from Tm3+in the interlayer to surface quenchers is suppressed, and thus, more active energy is trapped by activators, which induces the further change of upconversion emission color. Furthermore, the multicolor upconversion tuning can also be realized via Tb3+-mediated energy migration. 808 nm excited multicolor upconversion tuning, overcoming low tissue penetration and overheating effect under 980 nm excitation, improves the feasibility of upconversion nanoparticles in multicolor imaging and multiplexed detection areas.

This work shrinks down the size of Ge-on-Si photodetectors to reduce the dark current and maintain the optical responsivity by surrounding photonic crystals. Numerical simulation shows that the employment of photonic crystal in the Si slab effectively prohibits the radiation modes from those guided outgoing waves and facilitates light cyclic absorption in the epitaxial Ge region. A photodetector with a 5 μm long Ge absorption region is demonstrated with a dark current of 150 nA (1 μA up to 70°C), a 3 dB bandwidth of 17 GHz, and a responsivity of 0.75 A/W.

In order to incorporate linguistic information into decision making, it is necessary to apply computing with words (CW) techniques. Traditional CW models use only single and simple linguistic terms to represent both input and output, which limits the flexibility in information processing. Recent researches on computing with comparative linguistic expression, including extension models, has partially overcome this limitation. Nonetheless, the flexibility of linguistic information expression remains limited due to the discrete distributions of primary terms. A complete CW framework should include both encoding and decoding technologies for linguistic information, but previous researches have primarily focused on fuzzy encoding approaches, while ignoring fuzzy decoding techniques for linguistic expressions. To improve the accuracy and interpretability of CW in dealing with linguistic expressions, this research proposes a novel model called 2-tuple comparative linguistic expression (2-TCLE). To establish a framework for studying fuzzy representations of linguistic expressions, both fuzzy encoding and decoding approaches for 2-TCLE will be presented in a systematic manner that are performed to match each other. A novel linguistic computational model for dealing with 2-TCLE is presented and then applied to solve a multi-criteria group decision making case study. • A novel model named 2-TCLE is proposed. • Fuzzy encode approach for 2-TCLE is studied. • Fuzzy decode approach for 2-TCLE is studied. • A novel CW model dealing with 2-TCLE is provided. • The proposed CW model is applied to MCGDM. [ABSTRACT FROM AUTHOR]

A highly efficient transfer hydrogenation of α‐aryl selenomethyl ketones, using readily available chiral diamine‐derived ruthenium complex as a catalyst and a mixture of formic acid and triethylamine as a hydrogen source in dichloromethane under ambient conditions, is described. A wide range of chiral β‐hydroxy selenides was obtained in 90–99% ee values and moderate to good yields. The practicability is also demonstrated by a gram‐scale synthesis and downstream derivatization. A highly efficient transfer hydrogenation of α‐aryl selenomethyl ketones to chiral β‐hydroxy selenides catalysed by chiral diamine‐derived ruthenium complex with a mixture of formic acid and triethylamine as a hydrogen source is described.

Forage–livestock conflict (FLC) is a major anthropogenic cause of rangeland degradation. It poses tremendous threats to the environment owing to its adverse impacts on carbon sequestration, water supply and regulation, and biodiversity conservation. Existing policy interventions focus on the in situ FLCs induced by local production activities but overlook the role of consumption activities in driving FLCs. Here, we investigate the spatiotemporal variations in China’s FLCs and the domestic final consumers at the county level by combining remote sensing data and multi-regional input–output model. Results show that during 2005–2015, China’s pastoralism induced an average of 82 million tons of FLCs per year. Domestic final demand was responsible for 85–93% of the FLCs in China. There was spatiotemporal heterogeneity in domestic consumption driving China’s FLCs. In particular, the final demand of non-pastoral regions was responsible for around three-quarters (74–79%) of the total FLCs throughout the decade. The rangeland-based livestock raising, agricultural and sideline product processing, and catering sectors are important demand-side drivers. These findings can support targeted demand-side strategies and interregional cooperation to reduce China’s FLCs, thus mitigating rangeland degradation.

Surface-enhanced Raman scattering (SERS) is often impaired by the limited affinity of molecules to plasmonic substrates. Here, we use carbon fiber microelectrodes modified with silver nanoparticles as a plasmonic microsubstrate with tunable affinity for enrichment and molecular identification by SERS. The silver nanoparticles self-assemble by electrostatic interaction with diamine molecules that are electrochemically grafted onto the surface of the microelectrodes. β-carotene and trans-β-Apo-8′-carotenal, producing similar resonant SERS spectra, are employed as model molecules to study the effect of electroenrichment and SERS screening for different electrode potentials. The data show that at a characteristic electrode potential, the low affinity of polyene chains without hydrophilic groups to the substrate can be overcome. Different potentials were applied to recognize the two types of carotenoids by their typical SERS signal, and the applicability of this strategy was further confirmed in the environment of a real cell culture. The results indicate that by regulating the potential, carotenoid molecules with a similar molecular structure can be selectively quantified and identified by SERS. The developed SERS-active microelectrode is expected to help the development of portable, miniaturized point-of-care diagnostic SERS sensors.

Vacuum residue is utilized by a process involving the residue cracking and coke gasification regeneration. In this process, vacuum residue is first converted into the products of light olefins and light oils by catalytic cracking, and then the cracking-generated coke is gasified into H2-rich syngas by using a bifunctional base catalyst. Their cracking gasification effects of vacuum residue are studied in a dual fluidized bed reactor. The results show that the solid base catalysts could enhance light olefin yield (have high olefinicity) and inhibit the formation of coke in comparison with silica sand and a hydrothermal treatment zeolite catalyst (FCC catalyst). Furthermore, the catalyst prepared at a CaO/Al2O3molar ratio of 12:7 displayed a better cracking effect than the one produced at the molar ratio of 1:1. The effects of the reaction temperature and the catalyst-to-oil ratio on the distribution of cracking liquid from vacuum residue solid base cracking are discussed. The results showed that the heavy oil conversion of more than 93.0%, the light oil yield of about 81.0 wt %, the coke of ca. 5.2 wt %, and the C2–C3 olefinicity of higher than 53.0% are achieved by cracking at 700 °C with a catalyst-to-oil ratio of 7.0. The coke over solid base catalyst is well gasified at 800 °C in an atmosphere of steam–oxygen. The content of H2is about 55.5 vol % and with the CH4content of less than 0.2 vol % in comparison with 36.6 and 2.4 vol % over the FCC catalyst, respectively. The cracking effects of solid base catalysts are stable via a few cycles process, although a decrease in catalytic effect is observed.

In the Software-defined networking (SDN), when multiple control domains are used in control services, the transient state problem can occur causing the service flow interruption when border switches are updated a synchronously. We analyze the uniqueness of this problem for SDN, and propose a light-weight protocol for safe reconfiguration of the border switches in order to improve the availability of the services running in SDN. Our solution is designed as a generic supervision layer added in the control plane to support different types of services. To demonstrate the benefits, we implement a prototype of Information centric networks (ICN) with the protocol, and conduct experiments using Planet Lab. The results show the ICN service can continuously serve high volume requests for contents despite the congestions built by the heavy background traffic. The performance gains in terms of the mean and standard deviation of the content retrieve delay are 40.5% and 21.56%.

Abstract

Electro-optical hybrid logic is a potential solution to implement both electrical and optical signal processing, which receives analog or digital, electrical or optical signals and produces logic signals in a desired manner. In light of the transfer matrix theory, we found that one can steer light into different output ports of a multimode interference coupler by controlling the phases in a multivalued manner on the image-extended arms. This implementation acts as an analog-to-digital convertor from electric domain to optical domain. Also, an electrical-to-optical 2-to-2^2 binary-coded decoder is described and examined by the 3D beam propagation method.

High removal rate of polysilicon and high selectivity between silicon and oxide, are two important performance targets in DRAM chemical mechanical polishing (CMP). Traditionally, the polysilicon CMP is dominated by mechanical effects, owing to the relatively inert chemical property of silicon. We have shown that chemistry also played an important role in polysilicon polishing. In this paper, a novel polysilicon CMP slurry with an optimized chemistry is reported. It is specifically formulated for DRAM polysilicon polishing. It exhibits high removal rate, high selectivity (silicon/oxide), low defects and excellent surface quality.

No Abstract

Our previous studies in which neural tissue was transplanted into neonatal rat brains have demonstrated that the patterns of astrocyte migration are stereotypic and are mainly influenced by local factors in the host brain. Here we examine how these patterns are affected by the relative maturity of donor cells and recipient brains. In one group of animals, adult mouse corpus callosum was transplanted into the cortex or midbrain of neonatal rat brains; in a second group, corpus callosum from 2- to 3-day-old mice was placed in adult rats. The location of the grafts and the distribution of donor astrocytes were defined by using a monoclonal antibody (anti-M2) specific for mouse astrocytes. In marked contrast to previous studies involving transplantation into neonatal hosts, very few neonatal astrocytes placed into adult brains invaded the gray matter and these never migrated more than 250 μm from the graft. The migration in adult brains also failed to show targeted migration to regions such as the substantia nigra. In the second group, astrocytes from adult grafts implanted in neonatal hosts migrated in both gray and white matter of brains in patterns similar to those of neonatal cells placed in neonatal brains. These observations suggest that the astrocyte migration in the white and gray matter is guided by different cues and that the maturation of host brain environment, but not the age of donor cells, influences the pattern of cell migration.