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Unmanned aerial vehicle (UAV) has been utilized as an efficient data collector for Internet of Things (IoT) networks in sustainable industry 5.0. Whereas, how to sustain a stable power for the energy-constrained IoT devices (IoTDs) and to enhance the data gathering throughput of UAV-aided IoT networks via the wireless power transfer (WPT) or non-orthogonal multiple access (NOMA) is a twofold challenge. Thus, we propose to maximize the minimum UAV data collection throughput from the IoTDs via jointly optimizing the three-dimensional (3D) trajectories of two UAVs, scheduling and transmitting power of the IoTDs subject to the maximum flight velocity and minimum safe distance for the UAVs, as well as the harvested energy causality constraint for each IoTD during a finite UAV flight mission period. To tackle this non-convex problem with the strong interdependence of optimization parameters, we develop a 3D Trajectory Optimization and communication Resources Allocation Algorithm, named as TORAA, via employing the alternating optimization and successive convex approximation approaches, which alternately optimizes the UAVs’ 3D trajectories, the IoTDs’ scheduling and transmitting power sub-problems until the convergence criterion is met by the target function value. Moreover, we analyze the complexity and convergence characteristic of the TORAA. Numerous simulations have been performed to validate that the TORAA is capable of noteworthily enhancing the maximum minimum data collection throughput compared to the benchmark schemes with two-dimensional (2D) trajectories of the UAVs or constant transmitting power of the IoTDs.

AI-enabled logistics unmanned aerial vehicles (UAVs) are progressively revealing their unique advantages for future smart cities. Nevertheless, the existing research on logistics UAV path planning lacks to simultaneously consider the UAV energy consumption constraints, the customer time windows, the impacts of wind speed and direction. This omission renders the existing models inappropriate for real-world transportation systems. Besides, the UAVs are still constrained by the limited payload and battery due to the highly automatic delivery process. Consequently, we investigate the effect of wind speed and direction on UAV flight states, establishes pertinent parameters and their resolution methods impacted by wind conditions, and delves into the logistics UAV path planning issue that concurrently considers the UAV energy consumption constraints, the customer time windows, and the impact of wind conditions. To resolve the proposed trajectory optimization issue, the large-scale neighborhood search algorithm (LNS) is amalgamated with the genetic algorithm (GA), forming the GA-LNS, to address the static problem, while dynamic planning concepts are employed in the decoding process of GA-LNS to solve the dynamic trajectory optimization problem. Simulation results demonstrate that the devised algorithms yield superior solutions within a plausible timeframe, reducing distribution costs by approximately 9% in comparison to the conventional GA. Unlike the no-wind and static scenarios, path planning that incorporates dynamic wind conditions circumvents issues related to energy constraints and customer satisfaction bias evident in the prior cases. Furthermore, the proposed algorithm can provide a high-efficiency, low-energy-consumption, and low-delay UAV planning strategy in the scenario of UAV-assisted data collection.

In unmanned aerial vehicle (UAV)-assisted orthogonal frequency division multiplexing (OFDM) systems, the potential advantage of the line-of-sight (LoS) path, characterized by its high probability of existence, has not been fully harnessed, thereby impeding the improvement of channel estimation (CE) accuracy. Inspired by the ideas of integrated sensing and communication (ISAC), this letter develops a LoS sensing method aimed at detecting the presence of LoS path. Leveraging the prior information obtained from LoS path detection, the detection thresholds for resolvable paths are proposed for LoS and Non-LoS (NLoS) scenarios, respectively. By employing these specifically designed detection thresholds, denoising processing is applied to classical least square (LS) CE, thereby improving the CE accuracy. Simulation results validate the effectiveness of the proposed method in enhancing CE accuracy and demonstrate its robustness against parameter variations.

The three-dimensional (3-D) vibration-assisted turning (VAT) has attracted increasing attention for its merits in microstructure sculpturing and ultraprecision machining. However, most current 3-D VAT tools adopt complex structures and it is still difficult to implement high frequency and large amplitude simultaneously on a simple integrated tool. In this article, a 3-D VAT tool with high frequency and large amplitude adjustment capability is proposed for the first time, which adopts a more stable and compact single sandwich piezoelectric transducer structure. High frequency and large amplitude adjustment capabilities improve the machining efficiency and the range of machinable microstructures. The structure of the tool is simplified by using the sandwich-type single transducer structure, which is convenient to reduce cost and improve machining stability. Surface microstructures with variable inclination angles and distribution ratios are first sculptured by the proposed 3-D VAT tool, which provides a new idea for surface modification. In addition, surface microstructures with different depths and high-precision microgrooves are machined, and better machining results are obtained. The texture depth and machining efficiency of the microstructure are increased with the increase of amplitude and frequency. Microgrooves with a surface roughness of Sa 29 nm, minimized burrs and defects, and a specific cutting force reduction of 54.8% are obtained.

Climate change may affect water resources by altering various processes in natural ecosystems. Dynamic and statistical downscaling methods are commonly used to assess the impacts of climate change on water resources. Objectively, both methods have their own advantages and disadvantages. In the present study, we assessed the impacts of climate change on water resources during the future periods (2020–2029 and 2040–2049) in the upper reaches of the Kaidu River Basin, Xinjiang, China, and discussed the uncertainties in the research processes by integrating dynamic and statistical downscaling methods (regional climate models (RCMs) and general circulation modes (GCMs)) and utilizing these outputs. The reference period for this study is 1990–1999. The climate change trend is represented by three bias-corrected RCMs (i.e., Hadley Centre Global Environmental Model version 3 regional climate model (HadGEM3-RA), Regional Climate Model version 4 (RegCM4), and Seoul National University Meso-scale Model version 5 (SUN-MM5)) and an ensemble of GCMs on the basis of delta change method under two future scenarios (RCP4.5 and RCP8.5). We applied the hydrological SWAT (Soil and Water Assessment Tool) model which uses the RCMs/GCMs outputs as input to analyze the impacts of climate change on the stream flow and peak flow of the upper reaches of the Kaidu River Basin. The simulation of climate factors under future scenarios indicates that both temperature and precipitation in the study area will increase in the future compared with the reference period, with the largest increase of annual mean temperature and largest percentage increase of mean annual precipitation being of 2.4°C and 38.4%, respectively. Based on the results from bias correction of climate model outputs, we conclude that the accuracy of RCM (regional climate model) simulation is much better for temperature than for precipitation. The percentage increase in precipitation simulated by the three RCMs is generally higher than that simulated by the ensemble of GCMs. As for the changes in seasonal precipitation, RCMs exhibit a large percentage increase in seasonal precipitation in the wet season, while the ensemble of GCMs shows a large percentage increase in the dry season. Most of the hydrological simulations indicate that the total stream flow will decrease in the future due to the increase of evaporation, and the maximum percentage decrease can reach up to 22.3%. The possibility of peak flow increasing in the future is expected to higher than 99%. These results indicate that less water is likely to be available in the upper reaches of the Kaidu River Basin in the future, and that the temporal distribution of flow may become more concentrated.

The wind-dispersed seeds can rotate and fall like small vehicles with the help of the wind to obtain a longer propagation distance. Inspired by this, we propose a novel bubble-driven three-bladed whirling-swimmer (WS) to travel in the fluid as a vehicle. Four types of WSs with blade folding angles (φ) ranging from 10 to 60° were designed, and their swimming performance was evaluated. Regardless of the WS shape, the velocity increases linearly with φ, while the angular frequency exhibits an asymptotic value. Further, both the Stand rotational energy of the WS peak at 20° ≤ φ ≤ 30° for different WS shapes as well as the vertical force and the hydrodynamic torque were solved from a proposed mechanics model. This folding angle range is unexpectedly consistent with the coning angle during maple samaras’ stable falling. The WS lift and drag forces greatly depend on the interaction between the leading-edge vortex and the hub vortex. The results showed that the WS-IV seems to have the highest performance. Our work may shed new light on developing unpowered wireless swimmers of high swimming performance to provide a new way for underwater information collection, information transmission, and enhanced mixing.

The glucose metabolism of poultry draws wide attention as they have nearly twice the fasting blood glucose than that of mammals. To define the relationship between glucose metabolism and breed of chicken, the outcomes from different growth rate chickens showed that Arbor Acres (AA) broilers, a well-known fast-growing breed, had a lower fasting blood glucose concentration and glucose clearance rate when compared to Silky chickens, a Chinese traditional medicinal chicken with black skin and a slow growth rate. Moreover, AA broilers had a relatively slow rise in blood glucose in response to oral glucose solution than the Silky chickens on 21 and 42 d (P < 0.05), which is probably attributed to downregulated expression of pancreatic insulin (INS), and upregulated transcription of phosphoenolpyruvate carboxy kinase 1 (PCK1) and glucose transporter 2 (GLUT2) in the liver of AA broilers (P < 0.05). In response to feeding restriction from 7 to 21 d, both the fasting blood glucose and the response speed of AA broilers to oral glucose were increased on d 21 (P < 0.05), and the serum glucose concentrations after 3 weeks compensatory growth were improved by early feed restriction in AA broilers. Feed restriction could also upregulate the mRNA level of pancreatic INSon d 21 and 42, as well as decrease the expressions of PCK1, glucose-6-phosphatase catalytic (G6PC), and GLUT2in the liver on d 21 (P < 0.05) when compared to the free feeding group. These results revealed that Silky chickens have a stronger capability to regulate glucose homeostasis than AA broilers, and feed restriction could improve the fasting blood glucose and the response to oral glucose of AA broilers.

A synergistic pathway is regarded as a critical measure for tackling the intertwined challenges of climate change and air pollution in China. However, there is as yet no indicator that can comprehensively reflect such synergistic effects; hence, existing studies lack a consistent framework for comparison. Here, we introduce a new synergistic indicator defined as the pollutant generation per gross domestic product (GDP) and adopt an integrated analysis framework by linking the logarithmic mean Divisia index (LMDI) method, response surface model (RSM), and global exposure mortality model (GEMM) to evaluate the synergistic effects of carbon mitigation on both air pollutant reduction and public health in China. The results show that synergistic effects played an increasingly important role in the emissions mitigation of SO2, NOx, and primary particulate matter with an aerodynamic diameter no greater than 2.5 μm (PM2.5), and the synergistic mitigation of pollutants respectively increase from 3.1, 1.4, and 0.3 Mt during the 11th Five-Year Plan (FYP) (2006–2010) to 5.6, 3.7, and 1.9 Mt during the 12th FYP (2011–2015). Against the non-control scenario, synergistic effects alone contributed to a 15% reduction in annual mean PM2.5concentration, resulting in the prevention of 0.29 million (95% confidential interval: 0.28–0.30) PM2.5-attributable excess deaths in 2015. Synergistic benefits to air quality improvement and public health were remarkable in the developed and population-dense eastern provinces and municipalities. With the processes of urbanization and carbon neutrality in the future, synergistic effects are expected to continue to increase. Realizing climate targets in advance in developed regions would concurrently bring strong synergistic effects to air quality and public health.

Benefiting from the intrinsic convenience, flexibility, low cost, and unmanned aerial vehicles (UAVs) are envisioned to play an important role in future wireless communication systems. However, the limited on-board battery capacities and the broadcast characteristic of air-to-ground wireless channels bring some nonnegligible challenges on achieving secure UAV communications. To tackle these challenges, we propose to apply both the wireless power transfer and physical layer security techniques in a UAV communication system. We investigate the secrecy rate maximization problem by jointly optimizing the wireless charging duration, the trajectory, and transmit power of the UAV, subject to limited battery capacity, maximum flying speed, and energy-harvesting causal constraints. To solve this nonconvex problem, we first transform this problem into an equivalent problem with a smooth objective function, and then propose a low-complexity trajectory design and communication resources allocation algorithm for settling the reformulated problem via employing alternating optimization and SCP. Specifically, the reformulated problem is decomposed into three independent subproblems: the wireless charging duration optimization, the transmit power control, and the trajectory design of the UAV. Subsequently, we iteratively solve one of these three subproblems, while the others being fixed until the proposed algorithm converges. Extensive simulation results are provided to demonstrate that the proposed algorithm can significantly enhance the secrecy rate relative to the benchmark algorithms in absence of rechargeable battery or with fixed trajectory and transmit power.

Sodium dehydroacetate (DHA-Na) is a fungicidal preservative widely used in food and animal feed. DHA-Na can induce coagulation disorders in rats and poultry by inhibiting carboxylation of vitamin K-dependent proteins; it can also impair bone development in zebrafish. However, the effects of DHA-Na on broiler chicken bones remain unknown. Here, we assessed whether DHA-Na impairs bone development in broiler chickens. We administered Suji yellow chickens with 200 to 800 mg/kg DHA-Na, 2 mg/kg vitamin K, or both for 2 mo. Bone metabolite–related serum indicators, tissue micromorphology, and relevant protein expression were monitored during the treatment period. We also assessed primary chicken osteoblast activity, differentiation, and bone metabolite–related proteins after treatment with DHA-Na, vitamin K, or both. The results demonstrated that DHA-Na reduced bone index values and serum and bone osteoblast differentiation marker levels but blocked bone vitamin K cycle. DHA-Na also increased serum osteoclast differentiation marker levels, as well as the bone ratio of receptor activator of nuclear factor kappa-Β ligand to osteoprotegerin ratio. Moreover, DHA-Na reduced bone trabecular number, thickness, and area and increased trabecular separation considerably. In general, compared with the control group, the DHA-Na group demonstrated impairments in osteoblast activity and differentiation, as well as in the vitamin K cycle. By contrast, vitamin K supplementation led to considerable attenuation of the DHA-Na-induced decrease in osteogenic marker levels, along with a considerable increase in serum bone absorption marker levels and restoration of DHA-Na-induced bone microstructure damage. Vitamin K also attenuated DHA-Na-induced impairment in osteoclasts. In conclusion, the results indicated that in broiler chickens, DHA-Na supplementation can damage bones by inhibiting osteoblast function and increasing osteoclast activity; this damage can be prevented through vitamin K supplementation.

In order to improve the uniformity of the horizontal magnetic induction on the target surface, a cathode target configuration with a cylindrical permanent magnet inside and some cuboidal permanent magnets outside arranged roundly was designed for circular magnetron sputtering. The magnetic field was simulated by COMSOL software and verified by measurement. The experimental results were basically consistent with the simulation results. The magnetic field of the circular plane was distributed uniformly, and met the basic requirements of magnetic induction i.e. 20-50 mT for magnetron sputtering. The target utilization rate reached 40%-50%, and the heat dissipation capacity was improved to a certain extent. [ABSTRACT FROM AUTHOR]

Here, we present a method for Salmonelladetection using clustered regularly interspaced short palindromic repeats associated with the CRISPR-associated protein 12a-hybridization chain reaction (CRISPR/Cas12a-HCR) system combined with polymerase chain reaction/recombinase-assisted amplification (PCR/RAA) technology. The approach relies on the Salmonella invAgene as a biorecognition element and its amplification through PCR and RAA. In the presence of the target gene, Cas12a, guided by crRNA, recognizes and cleaves the amplification product, initiating the HCR. Fluorescently labeled single-stranded DNA (ssDNA) H1 and H2 were introduced, and the Salmonellaconcentration was determined based on the fluorescence intensity from the triggered HCR. Both assays demonstrate high specificity, sensitivity, simplicity, and rapidity. The detection range was 2 × 101–2 × 109CFU/mL, with an LOD of 20 CFU/mL, and the entire process enabled specific and rapid Salmonelladetection within 85–105 min. Field-incurred spiked recovery tests were conducted in mutton and beef samples using both assays, demonstrating satisfactory recovery and accuracy in animal-derived foods. By combining CRISPR/Cas12a with hybridization chain reaction technology, this study presents a rapid and sensitive Salmonelladetection method that is crucial for identifying pathogenic bacteria and monitoring food safety.

Multiple-input multiple-output (MIMO) is a promising technology to efficiently improve the achievable rate of white light-emitting diodes (LEDs) enabled visible light communication (VLC) systems. Nevertheless, for conventional MIMO techniques such as spatial diversity (SD) and spatial multiplexing (SMP), the working mode of each LED transmitter is independent of users’ spatial positions. In this article, we propose and investigate three user-centric MIMO techniques, including SD/SMP switching, adaptive SMP (aSMP), and SD-aided aSMP (SD-aSMP), for achievable rate improvement of indoor MIMO-VLC systems, by exploiting users’ spatial positions as a new degree of diversity. The analytical and simulation results show that the achievable rate of a 4 × 4 MIMO-VLC system in a typical indoor environment can be significantly improved by applying the user-centric MIMO techniques compared with the conventional ones. More specifically, SD/SMP switching can enjoy both high diversity gain of SD and high multiplexing gain of SMP at different signal-to-noise ratio (SNR) regions, while aSMP mitigates the adverse effect of noise amplification in conventional SMP and SD-aSMP can benefit from additional diversity gain. Furthermore, we also show that the proposed user-centric MIMO techniques outperform conventional MIMO techniques under the condition of only slightly increased computational complexity with limited feedback information.

In the context of climate change and over-exploitation of water resources, water shortage and water pollution in arid regions have become major constraints to local sustainable development. In this study, we established a Soil and Water Assessment Tool (SWAT) model for simulating non-point source (NPS) pollution in the irrigation area of the lower reaches of the Kaidu River Basin, based on spatial and attribute data (2010–2014). Four climate change scenarios (2040–2044) and two agricultural management scenarios were input into the SWAT model to quantify the effects of climate change and agricultural management on solvents and solutes of pollutants in the study area. The simulation results show that compared to the reference period (2010–2014), with a decline in streamflow from the Kaidu River, the average annual irrigation water consumption is expected to decrease by 3.84x108m3or 8.87% during the period of 2040–2044. Meanwhile, the average annual total nitrogen (TN) and total phosphorus (TP) in agricultural drainage canals will also increase by 10.50% and 30.06%, respectively. Through the implementation of agricultural management measures, the TN and TP in farmland drainage can be reduced by 14.49% and 16.03%, respectively, reaching 661.56 t and 12.99 t, accordingly, and the increasing water efficiency can save irrigation water consumption by 4.41 x108m3or 4.77%. The results indicate that although the water environment in the irrigation area in the lower reaches of the Kaidu River Basin is deteriorating, the situation can be improved by implementing appropriate agricultural production methods. The quantitative analysis results of NPS pollutants in the irrigation area under different scenarios provide a scientific basis for water environmental management in the Kaidu River Basin.

An ultrasensitive bio-barcode competitive immunoassay method based on droplet digital polymerase chain reaction (ddPCR) was developed for the determination of triazophos. Gold nanoparticles (AuNPs) were coated with monoclonal antibodies (mAbs) and complementary double-stranded DNA (dsDNA), which included bio-barcode DNA and thiol-capped DNA. Magnetic nanoparticle (MNP) probes were constructed by modifying the MNPs with ovalbumin–hapten conjugates (OVA–hapten). The target pesticide and OVA–hapten on the surface of the MNP probes competed with the AuNP probes simultaneously, and then the bio-barcode DNA was released for quantification by ddPCR. The concentration of released DNA was inversely proportional to the concentration of pesticide to be tested. Under the optimum conditions, the competitive immunoassay exhibited a wide linear range of 0.01–20 ng/mL and a low detection limit of 0.002 ng/mL. Spike recovery tests were carried out using apple, rice, cabbage, and cucumber samples to verify the feasibility of the method. The recovery and relative standard deviations (RSDs) of the technique ranged from 76.9 to 94.4% and from 10.8 to 19.9%, respectively. To further validate the results, a linear correlation analysis was performed between the proposed method and liquid chromatography–tandem mass spectrometry (LC–MS/MS). Consequently, the bio-barcode immunoassay based on nanoparticles and ddPCR, an ultrasensitive method, showed great potential for the determination of target pesticides in real samples.

In this letter, an intelligent resource allocation framework based on model-free reinforcement learning (RL) is first presented for multi-user integrated visible light communication and positioning (VLCP) systems, in order to maximize the sum rate of users while guaranteeing the users’ minimum data rates and positioning accuracy constraints. The learning framework can learn the optimal policy under unknown environment’s dynamics and the continuous-valued space, and a reward function is proposed to take into account the strict communication and positioning constraints. Moreover, a modified experience replay actor–critic (MERAC) RL approach is proposed to improve the learning efficiency and convergence speed, which efficiently collects the reliable experience and utilizes the most useful knowledge from the memory. Numerical results show that the MERAC approach can effectively learn to satisfy the strict constraints and achieve the fast convergence speed.

Visible light communication (VLC) systems utilizing conventional superposition coding/successive interference cancellation (SPC/SIC)-based non-orthogonal multiple access (NOMA) suffer from the error propagation effect due to imperfect SIC. In this letter, we propose a flexible-rate SIC-free NOMA technique for downlink VLC systems, based on constellation partitioning coding (CPC) and uneven constellation demapping (UCD). By using CPC/UCD, SIC is not required and hence error propagation can be eliminated in NOMA-based VLC systems. Moreover, by selecting a proper bit allocation scheme, flexible-rate multiple access can be supported in the VLC system applying CPC/UCD-based NOMA. Proof-of-concept two-user VLC experiments verify that, compared with conventional SPC/SIC-based NOMA, the bit error rate performance of the near user can be greatly improved by using CPC/UCD-based NOMA, and hence the effective power allocation ratio range can be substantially extended.

The ability of ICTP regional climate model version 4 (RegCM4.3) is investigated by using two land surface schemes: the biosphere-atmosphere transfer scheme (BATS) and the community land model version 3.5 (CLM3.5). To attain the best model configuration over the South Asia region, six sensitivity experiments are conducted with three different cumulus convection schemes. RegCM4.3 coupled with CLM3.5 and mixed convection scheme option (MIX-CLM), produced better simulation than BATS. The cold winter bias and the intensities of wet-dry biases over the foothills of Hindukush-Karakorum-Himalaya (HKH) and Central India are substantially reduced with MIX-CLM. In terms of seasonal variability, results suggest that different convection schemes behaved differently over sub-regions of the domain. The annual cycles of precipitation and temperature are better captured over the Bay of Bengal and Western Ghats by MIX-CLM. In spite of some deficiencies, the MIX-CLM scheme improves the model performance over the various parts of the domain.

Pyrethroids exist in numerous commercial insecticide formulations and have been used extensively all over the globe for pest control indoors and outdoors in many fields such as agriculture, public health, home use, and veterinary applications. The use of pyrethroids has increased continuously in recent years. This review aims to provide the latest research progress on newly developed haptens and antibodies, as well as their main applications in monitoring pyrethroid residues in the medical, environmental and agricultural fields. Two types of haptens were designed for pyrethroid insecticides. One recognized only a specific pyrethroid insecticide, whereas the other detected a series of pyrethroid insecticides with common molecular structures. Haptens and their conjugates were prepared to produce either monoclonal or polyclonal antibodies. The literature reviews have shown that a major trend for using enzyme immunoassay (EIA) methods to detect pyrethroid pesticide residues is to design universal immune haptens and prepare selective broad-spectrum antibodies. Besides, to develop immune detection methods for pyrethroid residues is an important research and development topic for monitoring the quality and safety of agricultural products worldwide.

Cu-doped muscovite(Mu) composite particles, abbreviated as Mu/Cu, were prepared vialiquid phase reduction method. The morphologies, phase composition and elementary distribution of the as-prepared Mu/Cu and raw muscovite particles were characterized by means of scanning electron microscope(SEM), X-ray diffraction(XRD) and energy dispersive spectrometry(EDS). The tirbological properties of Mu/Cu and Mu as lubricant additives in lithium grease were evaluated on a block-ring tribomachine. The roughness, 2D and 3D morphologies and elementary distribution of block worn surface were analyzed to explore the tribogical mechanism. The results show that muscovite are evenly coated by the cubic Cu nanoparticles in composite particles. Both Mu/Cu and Mu can effectively improve the tirbological properties of lithium grease and Mu/Cu exhibits better tribological performance than Mu. The friction coefficient of Mu/Cu is decreased by 69.2% as compared to that of lithium grease. The layer structure of muscovite is synergistic with Cu nanoparticles in contribution to the formation of lubricant film mainly consisting of O, Si, Fe, Cu as well as Al elements on the block worn surface thereby further reducing the friction and wear.

Fatty liver hemorrhagic syndrome is characterized by hepatic damage and hemorrhage impairing animal welfare in birds, which was well-known to be moderately relieved through dietary choline chloride supplementation in laying hens. Chinese herb has been proven to exert a positive role on hepatic health in human and rodents. Here, we investigated the effect of herbaceous mixture (HM), which consists of Andrographis paniculate, Silybum marianum, Azadirachta Indica, and Ocimum basilicum(2:3.5:1:2), on the hepatic lipid metabolism and health status in laying hens. A total of 240 Hy-line Brown hens (389-day-old) were randomly fed the basal diet with 0 mg/kg choline chloride (negative control, NC), 1,000 mg/kg choline chloride (control, Ctrl), or 300 mg/kg HM for 28 d. Birds fed HM diet exhibited lower serum triglyceride (TG) and low-density lipoprotein cholesterol concentration, and higher high-density lipoprotein cholesterol level than those received NC and Ctrl diets (P< 0.05). When compared to control and NC group, the diets with HM decreased the contents of total cholesterol and TG in liver, as well as upregulated the mRNA abundance of hepatic hormone-sensitive lipase and lipoprotein lipase. Meanwhile, the hepatic area and diameter of steatosis vacuoles were also decreased by dietary HM administration (P< 0.05), which accompanied by decreased serum alanine aminotransferase activity (P< 0.05). Birds fed HM diets enhanced the hepatic antioxidative capacity than those received NC and Ctrl diet. Dietary HM depressed the mRNA level of inflammatory cytokine as compared to NC but not Ctrl group. Collectively, the diet with 300 mg/kg HM has a favorable effect in decreasing the lipid deposition and protecting liver injury by alleviating hepatic oxidant stress and inflammation in post-peak laying hens.

A differential discrimination approach has been proposed in this paper to make fast discrimination from multi-returns in time-of-flight (TOF) systems. The time resolution of classical direct discrimination in a laser TOF system has been analyzed. A theoretical model of the differential discriminator has been established. As theoretical calculations and numerical simulations have shown, time resolution can be improved by using a differential discriminator instead of a classical direct discriminator, especially with large-amplitude signals. However, the relationship between the time resolution and the amplitude is not monotonic. The time resolution decreases as the amplitude decreases when the signals are small. But, through further analysis and simulations, a method to find an appropriate parameter, which can optimize the relationship curve, has been proposed. The theory and the simulations were verified by electrical circuit experiments, and the optical circuit experiments taken with two close targets of about 8.3 m. The FWHM of the laser is about 1.9 ns. The measured time resolution was better than 2.2 ns when the amplitude is 30 mV.

With the effective control of point source (PS) pollution accomplished, water pollution problems caused by non-point source (NPS) pollution have increased in recent years. The worsening agricultural NPS pollution has drawn the attention of the Chinese Government and researcher scientists and has resulted in the often mentioned “three red lines” on water resources management. One of the red lines is to control water pollution within a rational range. The Agricultural NPS pollution, which includes pollution from housing, and from livestock and crop production, is the main source. Based on the NPS pollution statutes, an index system for integrated evaluation of water quality, and a zoning scheme for rural water conservation were established. Using the method of one-dimensional Euclidean distance, this country is divided into 9 sub-zones at the provincial level, which are the first level zones. The zoning themes include natural resources, socio-economic development, water use efficiency, and pollutants emission intensity. According to pollution types of livestock, agriculture, or both, the first level zones are divided into 25 second level zones. The third class zoning is divided also based on pollution intensity of total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH3-N), chemical oxygen demand (COD), and biochemical oxygen demand (BOD). On the basis of the second level zoning, there were formed 70 rural water conservation third level zones. This case study in the Ashihe river watershed indicated that the main pollution sources are consistent with the zoning research result, and this zoning has shown a good way to guide the agricultural NPS pollution control in not only the wide rural area of China but also other parts of the world.

Influence of high-repetition-rate noise on a range-gated laser ranging and tracking system (LRTS) is studied both theoretically and experimentally. The interference mechanism of high-repetition-rate noise on range gates is revealed. The interference effect, especially the effect caused by relative shift between signal and noise, is presented through theoretical analysis and numerical simulation. In order to verify the simulation model, both electrical closed circuit and optical circuit experiments are further conducted. Both the simulation model and experiment results show that both periodic and nonperiodic noise pulses can enter the range gates of a LRTS and affect its operation with both their high repetition rate and relative shift to echo pulses.

We experimentally and theoretically investigate the effects of utilizing BaTiO3nanoparticles as additives in polythiophene/fullerene solar cells. BaTiO3nanoparticles were chosen because of their multifaceted potential for increasing exciton dissociation (due to their high dielectric constant) and light scattering. To achieve stable suspensions for device fabrication, the nanoparticles were functionalized with organic ligands. Solar cells fabricated in air showed ∼40% enhancement in the photocurrent primarily due to string-like aggregates of functionalized BaTiO3particles that increase light absorption without hindering charge collection. Solar cells fabricated in an inert atmosphere yielded overall more efficient devices, but the string-like aggregates were absent and enhancement in photocurrent was up to ∼6%. Simulations with the excitonic drift-diffusion model demonstrate that a bare nanoparticle significantly increases exciton dissociation, whereas the functional group negates this effect. Simulations utilizing the scattering matrix method reveal that absorption enhancements caused by light scattering increase as the nanoparticles aggregate into string-like structures. These results offer insights for morphological design of ternary-blend bulk-heterojunction organic solar cells.

Non-point source (NPS) pollution simulation in the high-precipitation coastal areas of China is difficult because varying annual typhoon incidence leads to highly contrasting rainfall patterns in dry years and wet years. An IMPULSE (Integrated Model of Non-point Sources Pollution Processes) based NPS model of the Changtan Reservoir watershed, which is a typical high-precipitation coastal area in China, was established based on the analysis of point and NPS pollution data, a digital elevation model, and data on land-use, soil, meteorology, economy, and agricultural management practice. Pre-processed pre-rainfall soil moisture levels were introduced during the simulation to model the effects of typhoons on hydrology. Rainfall events were simulated sequentially through the year and the model was calibrated and verified using hydrological and water quality data. Accuracy of the simulated rainfall runoff and water quality in the Changtan watershed was found to be acceptable. The study showed that the NPS modeling system could be applied to the simulation and prediction of NPS loadings in the Changtan Reservoir watershed.

A facile method was found to incorporate a mussel-inspired adhesive moiety into synthetic polymers, and mussel mimetic polyurethanes were developed as adhesive hydrogels. In these polymers, a urethane backbone was substituted for the polyamide chain of mussel adhesive proteins, and dopamine was appended to mimic the adhesive moiety of adhesive proteins. A series of mussel mimetic polyurethanes were created through a step-growth polymerization based on hexamethylene diisocyanate as a hard segment, PEG having different molecular weights as a soft segment, and lysine-dopamine as a chain extender. Upon a treatment with Fe3+, the aqueous mussel mimetic polyurethane solutions can be triggered by pH adjustment to form adhesive hydrogels instantaneously; these materials can be used as injectable adhesive hydrogels. Upon a treatment with NaIO4, the mussel mimetic polyurethane solutions can be cured in a controllable period of time. The successful combination of the unique mussel-inspired adhesive moiety with a tunable polyurethane structure can result in a new kind of mussel-inspired adhesive polymers.

A free space duplex communication system with a single laser and a modulated retro-reflector is presented. A method to minimize the echo wave bit error rate (BER) of this system is proposed by setting the optimum threshold automatically based on the measured mean power and irradiance variances with log-normal distribution and the Bayes minimum classification error criterion. Experiments were taken at a distance of 1.55 km in a weak turbulence and the measured BER was 0.0213. The BER performance of this system is studied and the result shows the experimental BER is in good accordance with the theoretical value.

Drinking water sources are highly valued by authorities for safeguarding the life of a city. Models are widely applied as important and effective tools in the management of water sources. However, it is difficult to apply models in water source management because water managers are often not equipped with the professional knowledge and operational skills necessary for making use of the models. This paper introduces a drinking water source simulation and prediction system that consists of a watershed model, a hydrological model and a water quality model. This system provides methods and technical guidance for the conventional management of water sources and emergency water event response. In this study, the sub-models of the system were developed based on the data of the Jiangdong Reservoir in Xiamen, and the model validation was based on local monitoring data. The hydrological model and water quality model were integrated by computer programming, and the watershed model was indirectly integrated into the system through a network platform. Furthermore, three applications for Jiangdong Reservoir water protection utilizing the system were introduced in this paper, including a conventional simulation, an emergency simulation, and an emergency measures evaluation.

Plant extract as the corrosion inhibitor has the multiple merits of inexpensive, eco-friendly and biodegradable. The corrosion inhibition of cold rolled steel (CRS) in dichloroacetic acid (Cl2HCCOOH) solution by Mikania micranthaextract (MME) was investigated by weight loss, electrochemical techniques and surface analysis. The results show that MME exhibits efficient inhibition, and the maximum inhibition efficiency is up to 91.2 % in 0.10 M Cl2HCCOOH. The adsorption of MME on CRS surface obeys Langmuir isotherm. The activation process from the reactant to transition state is endothermic. The inhibitive performance remains stable from 6 to 48 h at 20 and 30 °C, while drops initially from 6 to 24 h, and then keeps a steady state until 48 h. Increasing acid concentration leads to significant reduction of inhibitive action at 20 oC, while slightly decreases at 30 -50 °C. MME is a mixed-type inhibitor that drastically retards both cathodic and anodic reactions simultaneously. Electrochemical impedance spectroscopy has only one time constant, whose Nyquist appears a depressed capacitive loop, and there is only one peak in the Bode-phase plots. The radius of the capacitive arc gradually increases with the increase of MME concentration. Scanning electron microscopy and atomic force microscopy analyses can directly confirm that the addition of MME leads to a prominent reduction in corrosion as well as surface roughness of the CRS surface. The surface tension decreases with the increase of MME concentration. Besides ferulic and chlorogenic acids, other effective components in MME would contribute on the inhibitive action.

Abstract: Water environment security (WES) is defined in terms of three aspects: first, that it meets basic demands due to industrial and domestic usage; second, that it protects public health from acute and chronic threats; and third, that measures are adopted to ensure sustainable ecological functioning of freshwater resources. Limitations associated with current water environment security indicators in China — including inefficiency in terms of environmental monitoring, inappropriate indicators and parameters that do not take sufficient account of local water characteristics, and a lack of management targets —leads to a failure of effective water management. To achieve better water environment management, a systematic approach, encompassing several steps including establish ideal indicator system and narrow down the scope, screen priority pollutants, identify local characteristics and organize discussion workshop, should be followed to establish a comprehensive water environment indicator system. A case study in Suzhou is included to demonstrate the detailed operational procedures used to assess the risks associated with poor management practices relating to water environment security as well as design an appropriate water environment security indicator system.

Abstract: Characteristics of rainfall runoff from a 3.26 hm2 urban catchment with predominant land-use as lawn in Xiamen City, South-east China were investigated and analyzed. Water quality and quantity measurements of rainfall runoff were conducted for ten rainfall events over the period March, 2008 to April, 2009. The results indicated that chemical oxygen demand (COD) and total phosphorus (TP) were the major pollutants with event mean concentrations of 56.09 and 0.44 mg·L−1. From hydrograph and pollutograph analysis of two typical rainfall events, it was clear that the peak rainfall preceded the peak flowrate by about 15–20 min. Meanwhile, concentrations of major pollutants showed multiple peaks and these peaks usually preceded peak flowrate. There were no distinctive first-flush effects except for the rainfall events with the longest rainfall duration and largest runoff volume, which was verified by the fact that the first 30% runoff volume (FF30) carried 39.36% of the total suspended solids (TSS) load, 35.17% of the COD load, 28.13% of the TP load and 39.03% of the nitrate nitrogen load. Multivariate regression analysis further demonstrated that the total runoff volume had a positive correlation with the FF30 of TSS and COD.

Photonic generation of radio-frequency (RF) arbitrary microwave waveform with ultra-wide frequency tunable range based on a dispersion compensated optoelectronic oscillator (OEO) is proposed and experimentally demonstrated. Dispersion compensation scheme and specially designed fiber Bragg grating (FBG)-based Fabry–Perot (F-P) filters are employed in the OEO loop to realize a frequency tunable range of 3.5–45.4 GHz. An optimization process provided by the combination of an erbium-doped fiber amplifier (EDFA) and FBG is employed to improve the signal-to-noise ratio (SNR) of final RF signals. The generation of linear-frequency and phase-coded microwave waveforms, with a tunable carrier frequency ranging from 4 to 45 GHz and tuned chirping bandwidths or code rates, is experimentally demonstrated.

The output amplitude of the differential circuit is studied for differential discrimination in pulsed laser time-of-flight systems. Based on the studies of the probability of detection and the probability of false alarms, the minimum detectable input signal of differential discrimination can be calculated. The results indicate that the differential discrimination detectability of the small signal will be reduced. A combined discrimination is proposed in this Letter to improve the time resolution of the large signal and ensure the probability of detection of the small signal at the same time. A proper value of the circuit parameter is found to balance the time resolutions of the small and large signals.