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Transition-metal dichalcogenides (TMDs) have attracted intense research interest for a broad range of device applications. Atomic layer deposition (ALD), a CMOS compatible technique, can enable the preparation of high-quality TMD films on 8 to 12 in. wafers for large-scale circuit integration. However, the ALD growth mechanisms are still not fully understood. In this work, we systematically investigated the growth mechanisms for WS2and found them to be strongly affected by nucleation density and film thickness. Transmission electron microscope imaging reveals the coexistence and competition of lateral and vertical growth mechanisms at different growth stages, and the critical thicknesses for each mechanism are obtained. The in-plane lateral growth mode dominates when the film thickness remains less than 5.6 nm (8 layers), while the vertical growth mode dominates when the thickness is greater than 20 nm. From the resulting understanding of these growth mechanisms, the conditions for film deposition were optimized and a maximum grain size of 108 nm was achieved. WS2-based field-effect transistors were fabricated with electron mobility and on/off current ratio up to 3.21 cm2V–1s–1and 105, respectively. Particularly, this work proves the capability of synthesis of TMD films in a wafer scale with excellent controllability of thickness and morphology, enabling many potential applications other than transistors, such as nanowire- or nanosheet-based supercapacitors, batteries, sensors, and catalysis.

We present an experimental platform of operando nanoindentation that probes the dynamic mechanical behaviors of electrodes during real-time electrochemical reactions. The setup consists of a nanoindenter, an electrochemical station, and a custom fluid cell integrated into an inert environment. We evaluate the influence of the argon atmosphere, electrolyte solution, structural degradation and volumetric change of electrodes upon Li reactions, as well as the surface layer and substrate effects by control experiments. Results inform on the system limitations and capabilities, and provide guidelines on the best experimental practices. Furthermore, we present a thorough investigation of the elastic-viscoplastic properties of amorphous Si electrodes, during cell operation at different C-rates and at open circuit. Pure Li metal is characterized separately. We measure the continuous evolution of the elastic modulus, hardness, and creep stress exponent of lithiated Si and compare the results with prior reports. operando indentation will provide a reliable platform to understand the fundamental coupling between mechanics and electrochemistry in energy materials.

The plant genome produces an extremely large collection of long noncoding RNAs (lncRNAs) that are generally expressed in a context-specific manner and have pivotal roles in regulation of diverse biological processes. Here we mapped the transcriptional heterogeneity of lncRNAs and their associated gene regulatory networks at single-cell resolution. We generated a comprehensive cell atlas at the whole-organism level by integrative analysis of 28 published single-cell RNA-sequencing (scRNA-seq) datasets from Arabidopsisjuvenile seedlings. We then provided an in-depth analysis of cell type-related lncRNA signatures that shows consistent expression patterns with canonical protein-coding gene markers. We further demonstrated that the cell-type specific expression of lncRNAs largely explains their tissue specificity. In addition, we predicted gene regulatory networks based on motif enrichment and co-expression analysis of lncRNAs and mRNAs, and identified putative transcription factors orchestrating the cell type-specific lncRNA expression. The above analysis results are available at the single cell-based plant lncRNA atlas database (scPLAD; https://biobigdata.nju.edu.cn/scPLAD/). Overall, this work demonstrates the power of integrative single-cell data analysis applied to plant lncRNA biology and provides fundamental insights into lncRNA expression specificity and associated gene regulation.

“Saccharumcomplex” is a hypothetical group of species, which is supposed to be involved in the origin of modern sugarcane, and displays large genomes and complex chromosomal alterations. The utilization of restricted parents in breeding programs of modern cultivated sugarcane has resulted in a genetic blockage, which controlled its improvement because of the limited genetic diversity. The use of wild relatives is an effective way to broaden the genetic composition of cultivated sugarcane. Due to the infrequent characterization of genomes, the potential of wild relatives is diffused in improving the cultivated sugarcane. To characterize the genomes of the wild relatives, the genome size and phylogenetic relationships among eight species, including Saccharum spontaneum, Erianthus arundinaceus, E. fulvus, E. rockii, Narenga porphyrocoma, Miscanthus floridulus, Eulalia quadrinervis,and M. sinensiswere evaluated based on flow cytometry, genome surveys, K-mer analysis, chloroplast genome sequencing, and whole-genome SNPs analysis. We observed highly heterozygous genomes of S. spontaneum, E. rockii, and E. arundinaceusand the highly repetitive genome of E. fulvus. The genomes of Eulalia quadrinervis, N. porphyrocoma, M. sinensis, and M. floriduluswere highly complex. Phylogenetic results of the two approaches were dissimilar, however, both indicate E. fulvusdisplayed closer relationships to Miscanthusand Saccharumthan other species of Saccharumcomplex. Eulalia quadrinerviswas more closely related to M. floridulusthan M. sinensis; E. arundinaceusdiffer significantly from Miscanthus, Narenga,and Saccharum, but was relatively close to Erianthus.We proved the point of E. rockiiand E. fulvusshould not be classified as one genus, and E. fulvusshould be classified as the Saccharumgenus.

Fuel spray characteristics in a swirl-cup model annular combustor are investigated. In order to better quantify and distinguish the diameters and numbers of the fuel droplets, and their size distributions, image-processing technologies are applied for raw images of fuel spray field. These techniques include gradation processing, edge detection, smooth disposal, outline extraction and picture disposal. Experimental results show that the proposed image-processing technologies demonstrate an effective method for the characterization of the fuel spray field in the studied gas turbine combustor. Parametric studies were also conducted to investigate the influences of different inlet parameters such as inlet air temperature, inlet air flux and fuel air ratio on the spray field. It was found that the fuel atomization becomes better with the increase of inlet air temperature and fuel air ratio; however, the change of inlet air flux has a minimum effect on the spray field.

The three-dimensional flow-temperature numerical coupling model was established based on the Three-Dimensional Environment Fluid Dynamics Code Model. The reservoir water temperature was simulated coupled flow and water temperature and stratification pattern was analyzed attempting to provide scientific reference for water design and operation management on proposed reservoir, which could slow down the influence of low temperature water of proposed reservoir on ecological environment and aquatic biodiversity of the downstream river. Results show that reservoir water temperature stratification pattern distinguishes obviously among low temperature period, rising temperature period, high temperature period and cooling period and the temperature hysteresis effect is remarkable. The drainage of low-temperature water in summer should be prevented from influencing downstream ecological environment and the mechanism of the impact of high-temperature water in winter on ecological environment needs further study.

Background: Radiotherapy is the standard and most effective treatment for nasopharyngeal carcinoma (NPC) in its early stages. However, its application in fighter pilots returning to flying duties with NPC has not been previously reported, presumably due to post-radiotherapeutic complications. Case report: A 36-yr-old male fighter pilot had a painless mass in the left neck for 5 mo. Pathological diagnosis demonstrated nonkeratinizing squamous cell carcinoma in the left nasopharynx which had metastasized to lymph nodes in the left side of the neck. He was diagnosed and staged with NPC (T1N2M0) before treatment with radiotherapy and adjuvant chemotherapy. The patient suffered from catarrhal otitis media and xerostomia after 3 mo of radiotherapy, but these symptoms resolved. After a total of 8 mo of radiotherapy, he was in remission with no evidence of tumor recurrence or metastasis. He had normal Eustachian tube, hearing, and vestibular function before and after hypobaric chamber testing and passed all flight-related physical examinations. Consequently, he was granted a medical waiver and returned to flying status in two-seat fighter aircraft, flying for 53 h in a 12-mo period. After passing all flight-related tests again, he was then allowed to fly in single-seat aircraft. At the time of submission of this article, he has flown for 147 h and remained on flying status for 26 mo. He w ill be monitored annually for long-term effects of radiotherapy and/or disease recurrence. Conclusions: Fighter pilots with NPC may be safely considered for medical waiver with appropriate monitoring after successful treatment. [ABSTRACT FROM AUTHOR]

The article offers information on photographer Janice Chung who is photographing women in Queens, New York for her to understand her Korean American identity, along with her taken photographs including "Helen," "Mother Before Naptime," and "Visiting Big Aunt."

Background: Pulmonary sequestration is a rare congenital malfor-mation. The diagnosis of pulmonary sequestration is based on the iden-tification of an abnormal arterial supply. Conventional treatment for pulmonary sequestration is surgical removal of the tissue, which may induce serious trauma and requires a long recovery time. Recently, en-dovascular treatment has become feasible as a safer and less invasive method to treat pulmonary sequestration. Case report: To the best of our knowledge, pulmonary sequestration has not been reported in pilots. In this study, we report a fighter pilot case of intralobar pulmonary se-questration detected with the assistance of spiral computed tomography (CT) and digital subtraction angiography. The young fighter pilot had experienced recurrent hemoptysis and pulmonary infections for approx-imately 10 yr before the pulmonary sequestration was diagnosed. We performed a transcatheter arterial embolization and a subsequent CT angiography confirmed complete infarction of the sequestration. After the treatment, no clinical complications were observed and the patient, with normal lung function restored, was qualified to serve as a fighter pilot again. Discussion: Compared with conventional removal surgery, endovascular treatment is a superior treatment for pulmonary sequestra-tion in a fighter pilot in maintenance of pilot qualification. [ABSTRACT FROM AUTHOR]

A confined, quasi‐static uniaxial compression method, named as the compressive stiffness test (CST), is promoted to evaluate the quality of different RDX crystalline particles which are obtained from commercial and reprocessed lots. This method is based on the fact that the fragmentation or fracture behavior in the compression process could be correlated to the external/internal defects of targeted crystalline particles. The quality difference between the commonly used RDX and reprocessed RDX can be easily discriminated by compaction curves and the defined initial secant modulus can be used as a quantitative parameter to grade RDX particles. The results show that the RDX recrystallized from mixed solvents and spheroidized by treatment with solvent is of much higher quality than the commonly used RDX, and the particle size as well as external characteristics exert limited effects on the compaction curves, but the key factor is internal defects, which affect the coherence strength of RDX crystalline particles. Qualitative optical image analysis and quantitative particle apparent density measurements by liquid density gradient tubes also give consistent results with those from the CST.

Objective: To establish a new assay for platelet-activating factor (PAF), to compare it with bio-assay; and to discuss its significance in some elderly people diseases such as cerebral infarction and coronary, heart disease. Methods: To measure PAF levels in 100, controls, 23 elderly patients with cerebral infarction and 65 cases with coronary heart disease by reversed phase high-performance liquid chromatographic technique (rHPLC). Results: rHPLC is more convenient, sensitive, specific, and less confusing, compared with bio-assay. The level of plasma PAF in patients with cerebral infarction was higher than that in the controls (P<0.01), and in patients with coronary heart disease. Conclusion: Detection of PAF with rHPLC is more reliable and more accurate. The new assay has important significance in PAF research.

β-glucanase was purified from a solid-state culture ofTrichoderma reeseion wheat bran in three steps which comprised ammonium sulfate precipitation, Sephadex G-100 chromatography, and DEAE-Sephadex A-50 chromatography. The molecular mass was determined to be 35.21 kilodaltons by sodium dodecyl sulfate-12.5% polyacrylamide gel electrophoresis. The β-glucanase at low pHs was more stable than that at high pHs, and optimum pH was 5.0. The optimum temperature was 60°C, and β-glucanase was relatively stable at below 40°C for 60 min. TheKmof the enzyme on β-glucan was 10.86 mg/ml, and theVmaxon β-glucan was 14286 μmol of glucose equivalents per mg of the pure enzyme per min. The β-glucanase activity was significantly inhibited by Fe3+ions, and was reduced in the presence of Cu2+ions, Mn2+ions and Mg2+ions at 5 mmol/L and 10 mmol/L, respectively. The β-glucanase activity was stimulated by Co2+ions, Ca2+ions, Zn2+ions, and Fe2+ions at 1 mmol/L and 5 mmol/L, respectively.

The ingestion of giant freshwater prawn, Chinese prawn and giant tiger prawn had continuity and the ingestion high peak occurred at night. Light and temperature had significant effects on the daily ingestion rate (DIR) of giant freshwater prawnMacrobrachium rosenbergii. Red light and blue light favorably induced favorable ingestion. In the adaptive range of temperature, the DIR increased with rising temperature and feeding frequency, but decreased with rising body weight.

Temperature and the dissolved oxygen content affect the oxygen consumption of juveniles of Chinese prawn (Penaeus chinensis), giant tiger prawn (P. monodon) and giant freshwater prawn (Macrobrachium rosenbergii). There is good correlation between the oxygen consumption rate (V, mg/g·h) of the above three prawn species and the water temperature, and dissolved oxygen. In the range of test temperature,Vincreased with water temperature and dissolved oxygen content. TheVof the above three prawn species increased 0.085 mg/g·h, 0.093 mg/g·h and 0.08 mg/g·h respectively with each °C of rising temperature. The comatose point and stifling point of the juveniles rose obviously at unsuitable temperature.

Abnormal vocal cord mobility may result from trauma to the cricoarytenoid joint. A rabbit model of this kind of trauma was established in order to investigate pathological changes of the traumatized joint. Two types of pathological changes in the cricoarytenoid joint (acute inflammatory reaction in the early stage and fibrosis in the later stage) were noted. The above phenomena might be the mechanism of vocal cord dysfunction caused by trauma to the cricoarytenoid joint. The recovery of vocal cord function may depend on whether or not there is fibrosis of the cricoarytenoid joint. It is almost impossible to regain normal vocal cord function as soon as fibrosis of the joint occurs. Therefore, it is important to treat the patients effectively and immediately in the early stage of trauma for recovery.

Abstract: High temperature is an important factor inducing bacterial disease of the prawn (Penaeus orientalis). Water temperature over 35°C apparently stopped tested baculovirus from multiplying. High contents of ammonia-nitrogen and nitrite-nitrogen poison the prawn’s body, weaken its physique and may induce and worsen the disease.

This paper deals with the optimal distribution problem of large urban water supply system in our country. The mathematical model of the problem is developed. It possesses the separable, but nonconvex structure. The Lagrangian approach, representing the dual method, can not be used directly to solve this optimization problem. In order for primal-dual methods to be applicable to this type of large-scale and nonconvex optimization problem, a method by means of which a nonconvex problem is convexified is considered based on the principle of the multiplier approach in the paper. Under the transformation of the general multiplier approach, separability of the type песеззагу for applications of decomposition algorithms does not exist. The convexificat ion method proposed in this paper preserves the separablity of the problem. The decomposition-coordination optimization algorithm based on the convexification method and the multiplier approach is carefully discussed. The algorithm is not limited to the optimal distribution problem of water supply system. It may be used to solve other types of problems. The algorithm has been simulated in some real urban water supply systems. The satisfactory results are obtained.

Summary: We used the flow cytometric immunoassay to study the correlation between the tumor-suppressor gene product p53− and the DNA ploidy in 30de novo cases of acute nonlymphocytic leukemia (ANLL). The results showed that 15 cases were negative and the other 15 cases were positive expression for p53. As compared with p53 negative (p53) cases, the patients with positive p53 (p53+) had higher percentage of bone marrow blasts and lower peripheral leukocyte and platelet counts, which had no influence on the complete remission rate. Before treatment, DNA diploidy was seen in 18 cases including 12 p53− cases, and DNA aneuploidy in 12 cases including 9 p53+. After therapy, aneuploidy could be transformed into diploidy. Patients with P53+ or having aneuploidy in complete remission were at risk for early relapse. We believe that p53 may be involved in the process of leukemogenesis and progression of ANLL.

Abstract: This study deals with the hydrochemical state and management measures for the intermediate culture pond for Chinese prawn (Penaeus orientalis) juveniles. The test result showed that the intermediate culture of Chinese prawn juvenile can be advanced to around March 20 in the Shanghai area if they are cultured in ponds in simple greenhouses of plastic knitting cloth. The density of juveniles introduced was about 35 million per hectare, survival was up to 55%.

In this paper the hierarchical optimization of a nonlinear dynamical input-output model with time delays is studied. By combining the strategies of the costate prediction approach due to Hassan and Singh and the time delay algorithm by Tamura, the variable prediction-time decomposition technique is put forward. Based on the technique, the investment decision prediction method with three-level hierarchical optimization structure is proposed. An applied example and the conclusions obtained demonstrate that the method proposed by the paper is rather simple and effective when compared with those for linear model.

In this paper a multisubregional nonlinear dynamical waterenvironment-economy input-output model is developed which is based on the balance between production and use of outputs and the two-level scheme for treatment of water pollution. The model is combined with the water quality model of a river system in the regional area and a multisubregional waterenvironment-economy planning problem is established. In order to solve the large scale problem, a multiobjective hierarchical optimization algorithm is proposed. Theoretical analysis and computer simulation show that more factors are considered in the models and the calculations for optimization of planning are improved effectively by means of a hierarchical structure. So the method in the paper provides a useful tool for a regional waterenvironment-economy planning.

A test device is developed for studying the dynamic process of an electrowetting liquid lens. By analyzing the light signals through the liquid lens, the dynamical properties of the lens are investigated. In our experiment, three types of pulse, i.e., sine, bipolar pulse, and single pulse signals, are employed to drive the liquid lens, and the dynamic characteristics of the lens are subsequently analyzed. The results show that the positive and negative polarities of the driving voltage can cause a significant difference in the response of the liquid lens; meanwhile, the lens's response to the negative polarity of the driving voltage is clearer. We use the theory of charge restraint to explain this phenomenon, and it is concluded that the negative ions are more easily restrained by a dielectric layer. This work gives direct guidance for practical applications based on an electrowetting liquid lens.