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Assessing collective drug consumption based on the species and concentrations of illicit drugs and their metabolites in wastewater is an objective, real-time, accurate, convenient and effective monitoring technology. In order to establish a rapid screening and confirmation method for the abuse of opioids, amphetamines and benzodiazepines in wastewater, solid phase extraction was used to pretreat the wastewater sample, and ultra-high liquid chromatography tandem high resolution mass spectrometry was used to screen and confirm 36 kinds of analytes. Moreover, the method was applied to real wastewater samples collected from different wastewater treatment plants. Different HPLC columns and mobile phases were tested for optimization of the method. The peak shapes, retention time, separation and sensitivity of the chromatographic procedure were evaluated. Finally, an Accucore Hypersil Gold column (100 mm×2.1 mm×1.9 μm), and the mobile phases of ultrapure water with 2 mmol/L ammonium formate 0.1%-formic acid (A) and acetonitrile-methanol (1∶1, V/V) with 2 mmol/L ammonium formate and 0.1% formic acid were applied because of good peak shapes and separation. TraceFinder software was selected for rapid screening, and retention time, molecular mass, fragment ions and isotope distribution were collected as the screening basis. A substance could be judged as positive if it all met these 4 screening conditions. Therefore, the results obtained were more authentic and reliable. The LODs ranged from 5 to 20 ng/L. The extraction recoveries were higher than 70% for all compounds in wastewater, and the matrix effect ranged from -24.4% to 21.2%. In the real wastewater samples, 4 opioids of morphine, codeine, pethidine, tramadol, 1 amphetamine of methamphetamine and 4 benzodiazepines of diazepam, nordazepam, estazolam, alprazolam were detected, and the error of all compounds were less than 5×10-6. There are many kinds of abused substances in wastewater, and the regional prevalence is also different. The method established in this article can be used for rapid and accurate screening and confirmation abused substances in wastewater.

This paper proposes an image reconstruction method for simultaneous multi-slice imaging (SMS) by combining the virtual conjugate coil (VCC) technology and robust artificial-neural-networks for k-space interpolation (RAKI). This method can effectively improve the reconstruction quality, and is named VIRGINIA (VIRtual conjuGate coIls Neural-networks InterpolAtion). VIRGINIA utilizes the complex conjugate symmetry property of the virtual coil concept to generate virtual coil data for training, and obtains better image quality by applying the trained network to the original aliased SMS data. With experimental data, the VIRGINIA method was compared to other reconstruction methods (i.e., RAKI only and slice-GRAPPA) in terms of quantitative indices such as structural similarity index (SSIM), peak signal-to-noise ratio (PSNR) and root mean square error (RMSE). The results demonstrated that, under some certain slice-acceleration factors, VIRGINIA produced better reconstruction quality than those obtainable by Slice-GRAPPA and RAKI.

Integration of order acceptance and scheduling on unrelated parallel machines is a joint decision problem, and arise from the multi-variety customized production environment, which usually has the following characteristics. First, there are a number of parallel machines (production lines), each of which can only produce a limited variety of products referred as the machine-eligibility constraint. Second, the processing technologies of various machines differ; thus, these parallel machines are unrelated. Third, because the machines are unrelated, the setup time of an order is related not only to the order sequence but also to the machine used, which is called a sequence-and machine-dependent setup time. To minimize total cost, this study investigates the scheduling problems posed by order acceptance and unrelated parallel machines with setup time and machine-eligibility constraints. In this problem, an order has two options, rejection or acceptance. If an order is rejected, it generates a rejection cost. Otherwise, the order process must be completed before the due date, or there will be a tardiness cost. Therefore, the total cost spent is calculated as the sum of the total rejection cost of rejected orders and total weighted tardiness cost of accepted orders. To solve this problem, the effect of rejecting an order on the total cost was analyzed, and a list of rejecting methods and rejection rules were proposed. Furthermore, a cooperative coevolving genetic algorithm (CCGA) was developed. In this CCGA, an encoding scheme was proposed that divides chromosomes into two subsets corresponding to the order list and order assignment. Moreover, a list-rejecting-based decoding procedure was presented for deciding rejection for a chromosome. As the two subsets are independent of each other and their evolutionary constraints are essentially different, a cooperative coevolution strategy was applied to evolve the subpopulations of these subsets using partheno-genetic and traditional genetic operators. Computational experiments on a large set of randomly generated instances were performed to verify the effectiveness and efficiency of this algorithm. Additionally, the impacts of problem size and rejection cost were studied experimentally. The results reveal that in the majority of cases characterized by various problem sizes and rejection costs, the proposed algorithm performs effectively and efficiently.

The CO2 huff-n-puff is an effective substitute technology to further improve oil recovery of natural fractured tight oil reservoirs after water flooding, for its high displacement efficiency and superior injectivity. The CO2 huff-n-puff process is influenced by many factors, such as miscible degree, complex fracture networks, and production schemes. What is worse, those influence facts affect each other making the process more complex. Many researchers concentrated on mechanisms and single sensitivity analysis of CO2 huff-n-puff process, whereas few optimized this process with the consideration of all influence factors and multiobjective to get favorable performance. We built multiobjective consisted of miscible degree, oil recovery, and gas replacing oil rate considering the aspects of CO2 flooding special characteristic, technical effectiveness, and economic feasibility, respectively. We have taken Yuan 284 tight oil block as a case, firstly investigated sensitivity analysis, and then optimized CO2 huff-n-puff process using orthogonal experiment design with multifactors and multiobjectives. The optimization results show CO2 huff-n-puff can significantly improve oil recovery by 8.87% original oil in place (OOIP) compared with water flooding, which offers guidelines for field operations.

A traceable method is presented, to study the purities of certified reference material of 1,2,3,4-tetrachlorobenzene with the assessment of uncertainties. The purities of 1,2,3,4-tetrachlorobenzene were determined by the mass balance method. The qualitative analysis of main non-volatile impurities was identified as 1,2,3,5-tetrachlorobenzene with Gas Chromatography-Mass Spectrometry (GC-MS) and standard addition. The quantitative analysis for the impurities was measured by Gas Chromatography-Flame Ionization Detector (GC-FID). The content of water and ash in 1,2,3,4-tetrachlorobenzene were respectively measured by Karl-Fischer titrator and ignited at 900℃ in a muffler roaster. The residuals of solvent were confirmed as ethyl ether by Headspace Gas Chromatography-Mass Spectrometry. The certified result with the mass balance method was 98.79% and the expanded uncertainty was 0.20% (k=2). The good homogeneity result in the 95% confidence interval was validated by F-test and t-test statistical methods with samples from 500 different bottles. The stability inspection was carried out on short-term (one month) and long-term (12 months) tests, and the results indicate that the stability period for 1,2,3,4-tetrachlorobenzene of storage is no less than 12 months at 20℃.

.In view of the problem of poor error stability of the three-phase energy meter verification device under low current load, the working principle and error calculation method of the device are analyzed. The harmonics content and error data of the device under low current load before and after the installation of the isolation transformer are tested on site. And the role of the isolation transformer in suppressing the harmonics of the device is analyzed. From the harmonics content and error data of the output current of the device before and after the installation of the isolation transformer, it can be seen that the isolation transformer can effectively suppress the harmonics content of the device at the time of low current output and also improve the error stability under low current load.

With the development of GPU general-purpose computing, GPU heterogeneous cluster has become a widely used parallel data processing solution in modern data center. Temperature management and controlling has become a new research hotspot in big data continuous computing. Temperature heat island in cluster has important influence on computing reliability and energy efficiency. In order to prevent the occurrence of GPU cluster temperature heat island, a big data task scheduling model for preventing temperature heat island was proposed. In this model, temperature, reliability and computing performance are taken into account to reduce node performance difference and improve throughput per unit time in cluster. Temperature heat islands caused by slow nodes are prevented by optimizing scheduling. The experimental results show that the proposed scheme can control node temperature and prevent the occurrence of temperature heat island under the premise of guaranteeing computing performance and reliability.

Summary: As an essential macronutrient, phosphorus (P) is often a limiting nutrient because of its low availability and mobility in soils. Drought is a major environmental stress that reduces crop yield. How plants balance and combine P‐starvation responses (PSRs) and drought resistance is unclear. In this study, we identified the transcription factor ZmPHR1 as a major regulator of PSRs that modulates phosphate (Pi) signaling and homeostasis. We found that maize zmphr1 mutants had reduced P concentration and were sensitive to Pi starvation, whereas ZmPHR1‐OE lines displayed elevated Pi concentration and yields. In addition, 57% of PSR genes and nearly 70% of ZmPHR1‐regulated PSR genes in leaves were transcriptionally responsive to drought. Under moderate and early drought conditions, the Pi concentration of maize decreased, and PSR genes were up‐regulated before drought‐responsive genes. The ZmPHR1‐OE lines exhibited drought‐resistant phenotypes and reduced stomatal apertures, whereas the opposite was true of the zmphr1 mutants. ZmPT7‐OE lines and zmspx3 mutants, which had elevated Pi concentration, also exhibited drought resistance, but zmpt7 mutants were sensitive to drought. Our results suggest that ZmPHR1 plays a central role in integrating Pi and drought signals and that Pi homeostasis improves the ability of maize to combat drought. [ABSTRACT FROM AUTHOR]

Anode‐free and anode‐less lithium (Li) metal batteries provide cell safety and afford maximum energy density. However, their practical applications are hampered by poor cycling performances. In this study, a composite of LiC6 phase in highly reduced graphene (HrGO, LC‐HrGO) is proposed as a current collector for Li metal plating. LC‐HrGO provided homogenous plating sites and favorable conductivity, which facilitated Li metal plating with reduced nucleation barrier. The LiC6 in composite is not easily delithiated, and the HrGO is not easily lithiated. The obtained anode‐free batteries based on the LC‐HrGO current collector showed a capacity retention of 60 % after 100 cycles, and the corresponding anode‐less batteries indicated a stable specific capacity of 134.5 mAh g−1 after 250 cycles and a remarkable rate capacity of 130.1 mA h g−1 at 5 C. The work provides valuable concepts for fabricating promising current collectors towards Li metal batteries and beyond for high‐level services. [ABSTRACT FROM AUTHOR]

Background: Foreign body-induced cancer is a traditional way of understanding cancer development. The induction of cancers by exogenous foreign bodies has been identified in many organs. However, small bowel adenocarcinoma induced by foreign bodies has not been reported in the literature, although the incidence of small bowel adenocarcinoma is increasing globally. Case Presentation: A 70-year-old man was hospitalized for persistent right-sided abdominal pain for 3 months. Abdominal computed tomography revealed localized thickening and clustering of the small bowel wall in the right abdominal cavity. A comminuted fracture of the right 11th rib protruding into the abdominal cavity was observed, with a bone fragment located within the intestinal mass. Exploratory laparotomy was performed, and extensive adhesions were noted among the greater omentum, small bowel, mesentery, and right abdominal wall. Radical resection and lymph node dissection of the affected small bowel and appendix were performed. We also excised the rib end and repaired the abdominal wall to prevent further irritation. The patient was discharged 12 days post-surgery and follow-up assessments revealed no reported discomfort. Conclusion: We first report a case of small bowel adenocarcinoma induced by self-bone tissue, along with successful radical tumor excision and thorough foreign body removal. This case highlights the significant role of chronic inflammation in carcinogenesis. [ABSTRACT FROM AUTHOR]

A new compound, vestitain A (1), together with 11 known compounds were isolated from the ripe fruits of Embelia vestita Roxb., among them compounds 5,10-12 were isolated from this plant for the first time. Their structures were elucidated and characterized by detailed spectroscopic analysis. Further, the isolated new compound 1 was evaluated for its hypoglycemic effects in vivo. Our research showed that compound 1 could decrease the fasting blood glucose (FBG) by approximately 36.31% in diabetic rats at the high dose (800 mg/kg). By the Morris Water Maze experiments, we found that compound 1 had the effect of intervention on social behavior in diabetic rats, which might provide a reference basis for its development and utilization as a potential hypoglycemic drug. [ABSTRACT FROM AUTHOR]