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The paper considers direct and inverse elastic scattering from a cavity in homogeneous medium with Dirichlet and Neumann boundary conditions. For direct scattering, existence and uniqueness are derived by variation approach. For inverse scattering, Fr$\acute{\rm e}$chet derivatives of the solution operators are investigated, which give local stability for Dirichlet case.

In order to optimize the position of the micro-texture on the negative chamfering edge ball-end milling cutter, the experiment of milling titanium alloy with the negative chamfering micro-texture b...

Background Exploration of adaptive evolution of organisms in response to environmental change can help to understand the evolutionary history of species and the underlying mechanisms of adaptation to local environments, thus guiding future conservation programmes. Before the introduction of Apis mellifera in China, eastern honey bees (Apis cerana) were the only species used for beekeeping in this region. In the mountains of Changbai, populations of A. cerana are considered a distinct ecotype of the species which formed through the distinct selective pressures in this area over time. Result We performed a measure of 300 wing specimens of eastern honey bees and obtained the geometric morphological variation in the wing of A. cerana in Changbai Mountain. A total of 3,859,573 high-quality SNP loci were yielded via the whole-genome resequencing of 130 individuals in 5 geographic regions. Conclusion Corresponding geometric morphology and population genomics confirmed the particularity of the A. cerana in Changbai Mountain. Genetic differentiation at the subspecies level exists between populations in Changbai Mountain and remaining geographic regions, and a significant reduction in the effective population size and an excessive degree of inbreeding may be responsible for a substantial loss of population genetic diversity. Candidate genes potentially associated with cold environmental adaptations in populations under natural selection were identified, which may represent local adaptations in populations. Our study provided insights into the evolutionary history and adaptation of A. cerana in Changbai Mountain, as well as its conservation.

Text mining has been a dominant approach to extracting useful information from massive unstructured data online. But existing tools for Chinese word segmentation are not ideal for processing social media text data in Cantonese. This project developed CyberCan (https://github.com/shenfei1010/CyberCan), a lexicon of contemporary Cantonese based on more than 100 million pieces of internet texts. We compared the performance of CyberCan with existing Mandarin and Cantonese lexicons in terms of their word segmentation performance. Findings suggest that CyberCan outperforms all existing lexicons by a considerable margin.

Additional file 10 Fig. S6. Photos showing the phenotypes of red deer and sika deer.

Additional file 5 Fig. S2. A-F indicate the SNP sites that could be accurately classified by the default parameters of GenomeStudio (those with the first and second patterns (Fig. S2A, B). All formed a single cluster (AA, 00, 00; 00, 00, BB), representing a monomorphic locus. Those with the third and fourth patterns (Fig. S2C, D, E, F) were markers that showed three (AA, AB, AB) and two (AA, 00, BB; AA, AB, 00) clearly definable clusters.

Additional file 11 Fig. S7. Photos showing the phenotypes of hybrid deer.

INTRODUCTION: Autosomal recessive (AR) and x-linked (XL) conditions are rare but collectively common which impact millions of people globally on morbidity, mortality and costs. Advanced medical technologies allow prospective parents to make informed reproductive decisions to avoid having affected children. Economic evaluations targeting on reproductive carrier screening (RCS) for AR and/or XL conditions have been conducted, but there has not been a systematic review in this area. AREAS COVERED: A systematic search of economic evaluations for RCS was undertaken using the following databases - EMBASE, MEDLINE and SCOPUS. The search strategy was designed to capture full economic evaluations related to RCS since 1990. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) strategy. The included 23 studies adopted various types of methodologies to conduct economic evaluations. The majority of studies examined a single condition. The various clinical strategies and screened conditions caused the different cost-effectiveness conclusions in the published studies. EXPERT OPINION: Establishing a validated and practical clinical strategy of RCS and investigating the cost-effectiveness of multiple conditions in one economic evaluation are critical for implementing RCS in the future. Further economic evaluations are essential to provide evidence-based practice for decision-makers.

Additional file 6 Fig. S3. A, B indicate the SNP sites that could not be accurately classified even with software adjustment.

Additional file 1 Fig. S1. Fst values of SNP sites on different chromosomes.

Additional file 8 Fig. S4. Venn diagram of sites for analysis. As can be seen from the figure, a total of 991 chip sites have been detected, 973 for MAF > 0.05, 850 for Call Rate > 95%, and 833 for SNP that meets MAF > 0.05 and Call Rate > 95%.

Lots of multi-layer heterogeneous sandstone reservoirs have reached extreme high water content and high recovery after long-time water-flooding development, and their low-permeability thin oil layers (LPTOLs) have gradually been the main potential reserves. Therefore, taking the geology of LPTOLs into account, an independent water-flooding development (IWD) method with stratified hydraulic fracturing (SHF) for LPTOLs is put forward. The method combines undeveloped LPTOLs as an individual strata series in one injection-production system, and the HPTOLs even with low water content are abandoned in order to reduce the reservoir vertical heterogeneity. To realize economic benefits, mature stratified hydraulic fracturing is necessary to increase production. The key of IWD is selecting and combining appropriate LPTOLs in an individual strata series. Two development modes, OW-OL and WW-OL, are designed by different wells' perforations and the oil layers' distribution. The difference between these two modes mainly depends on whether the oil-wells perforate the HPTOLs connected with the LPTOLs. Upon an embedded fracture model for simulating hydraulic fractures, the oil production and water content of one LPTOL are calculated with different physical factors of reservoir and fractures. According to the cumulative oil production under different factors, their impact degrees are evaluated by gray relative analysis method. Permeability, oil layer thickness and oil viscosity are three main factors influencing the development of LPTOLs, and flow coefficient is a comprehensive index composed of these three factors. Therefore, the flow coefficient variation degree is a core indicator to evaluate the vertical heterogeneity of an individual strata series, and IWD will get better water-flooding effect with lower flow coefficient variation degree. In order to analyze the effect of IWD, 30 cases are designed with different flow coefficient variation degree, different thickness of HPTOL and different IWD modes. Oil production and water content variation of two development modes are studied by simulation. OW-OL mode is superior to the WW-OL mode on water-flooding recovery. That is because the oil is mainly produced from layered-LPTOLs with less water content, the vertical water-flooding efficiency is higher at the production side, and the whole displacement is more balanced in the whole OW-OL strata series. IWD of LPTOLs is not only suitable for Chinese sandstone oilfields, but also has a general significance for other multi-layer sandstone reservoirs owing high-potential LPTOLs.

The Electric Conductivity of Stirred Clayey sediments into Water (EC), pH values and micropalaeontological studies of the underlying muddy sediments of the buried oyster reefs in Dawuzhuang and Airport sites, northwest coastal plain of Bohai Bay revealed a difference of the depositional environments of the underlying mud units in two sites. In Dawuzhuang, from the underlying to the overlying muds, environment changed from subtidal to the lower intertidal zone, which presented a falling tendency of relative sea level. However, the underlying mud in Airport site occurred in the intertidal and changed upwards to the reef body as being lagoonal environment. These indicate that the relative sea level fall resulted in intertidal environment in Dawuzhuang and a change from the open intertidal to relatively isolated intertidal lagoon environment in Airport site as a diatom thriving as well during the mid-Holocene all form the important reasons for the oyster reef development.

Genetic diseases of blood cells are prime candidates for treatment through ex vivo gene editing of CD34+ hematopoietic stem/progenitor cells (HSPCs), and a variety of technologies have been proposed to treat these disorders. Sickle cell disease (SCD) is a recessive genetic disorder caused by a single-nucleotide polymorphism in the β-globin gene (HBB). Sickle hemoglobin damages erythrocytes, causing vasoocclusion, severe pain, progressive organ damage, and premature death. We optimize design and delivery parameters of a ribonucleoprotein (RNP) complex comprising Cas9 protein and unmodified single guide RNA, together with a single-stranded DNA oligonucleotide donor (ssODN), to enable efficient replacement of the SCD mutation in human HSPCs. Corrected HSPCs from SCD patients produced less sickle hemoglobin RNA and protein and correspondingly increased wild-type hemoglobin when differentiated into erythroblasts. When engrafted into immunocompromised mice, ex vivo treated human HSPCs maintain SCD gene edits throughout 16 weeks at a level likely to have clinical benefit. These results demonstrate that an accessible approach combining Cas9 RNP with an ssODN can mediate efficient HSPC genome editing, enables investigator-led exploration of gene editing reagents in primary hematopoietic stem cells, and suggests a path toward the development of new gene editing treatments for SCD and other hematopoietic diseases.

Quantum evolutionary learning algorithm is a kind of fast algorithm which search the optimal solution of functions, with the help of Quantum thinking, this kind of algorithm has a high degree of parallelism, and the nature of fast speed. In this paper a frame work of quantum genetic search which is based on laser lidar image, in this frame work, a method of image quantum formulation is proposed, a wave function is used to describe the solution space to be searched, which makes the operand transformed from determined points to the whole solution space. Besides, an unequal probability initialization is shown in this paper, which solves the problem of misconvergence in the general initializations. What is more, an adaptive quantum rotary gate is designed to accelerate the convergence of the algorithm, which is adjusted automatically with the evolutional generation and fitness. The frame work given in this paper was applied in the target searching of streak tube imaging lidar, and shows rapid convergence and high stability with the premise of high-precision.