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At present, medical ultrasound technology is gradually developing from the traditional imagingof tissue and organ structure based on wave effect of ultrasound, and the treatment of diseased tissue based on thermal and cavitation effects, to the direction of multi-functional integration of diagnosis and treatment. Therefore, asone of the most important biological effects, the mechanical effect of ultrasound (i.e. acoustic radiation force) hasattracted more and more attention from scientific researchers and medical staffs. Benefiting from the in-depthunderstanding of the theory and mechanism of ultrasonic mechanical effect, as well as the rapid development ofinformation and electronic technology, a variety of new ultrasonic diagnosis and treatment technologies based onacoustic radiation force have emerged in recent years, which have greatly expanded the application of ultrasoundin clinics. For example, ultrasound elastography that can quantitatively measure the tissue stiffness and image itsdistribution, which can provide early screening for liver cirrhosis and breast cancer; as well as ultrasound neuromodulation that can non-invasively regulate the state of nerve cells in the brain, which can provide unique toolsfor brain disease treatment and neuroscience research. This article will systematically introduce the representativeachievements of these new medical ultrasound technologies based on the mechanical effect of ultrasound in recentyears, and analyze their future development directions.

Abstract Background Mutations in CNKSR2 have been described in patients with neurodevelopmental disorders characterized by childhood epilepsy, language deficits, and attention problems. The encoded protein plays an important role in synaptic function. Case presentation Whole-exome sequencing was applied to detect pathogenic variants in a patient with clinical symptoms of psychomotor development, attention deficit, poor logical thinking ability, and an introverted personality, but without epilepsy or any significant electroencephalogram changes. Genetic study revealed a splicing mutation (c.1904 + 1G > A) and RT-PCR revealed aberrant splicing of exon 16, leading to a reading-frame shift and a truncated protein in the PH domain. Conclusions This is the first report of a splicing variant of CNKSR2, and the unique clinical features of this pedigree will help extend our understanding of the genetic and phenotypic spectra of CNKSR2-related disorders.

In order to solve the problem of ship wake detection in synthetic aperture radar (SAR) image, a coherent speckle noise suppression algorithm based on analytic dictionary and a wake detection algorithm based on Radon transform are proposed. First, the morphological component separation algorithm based on analytic dictionary is used to separate the components of SAR image. The structural component image with ship wake and the texture component image with speckle noise and sea clutter are obtained. Then, the local Radon transform is performed on the structural component that contains the ship wakes. Finally, the real and false local peak points are distinguished by the ship wake recognition algorithm based on peak clustering decision, so as to obtain the local peak points generated by the real wakes and determine the specific position of the ship wakes. The experimental results show that the proposed algorithm can effectively detect the ship wakes in SAR images.

A modified progressive damage model is constructed to analyze the damage mechanics and damage development of composite laminates induced by low-velocity impact in this article. The damage modes are judged by the 3D Hashin failure criterion. A modified damage evolution model, which was constructed based on through-thickness normal strain component ε 33 , is implemented to describe progressive damage of composites. Cohesive elements with quadratic failure criterion and B-K criterion are applied to simulate the development of delamination. The 3D Hashin criterion and modified damage evolution model are coded in VUMAT and called in the ABAQUS/Explicit package. The damage distribution and mechanical behavior, including impactor energy, react force, displacement, predicted by numerical simulation are compared with the experimental data of different impact energies (7.35, 11.03, and 14.70 J). The numerical results and experimental data are in good agreement, which suggests that the modified damage evolution model is beneficial for studying the dynamic mechanical behavior during impact. Moreover, the influence of cohesive element thickness on numerical results is discussed. It is concluded that the cohesive element thickness should be adopted between 0.001 and 0.0075 mm.

The work presents a detailed investigation of mechanical properties and deformation mechanism of ultrathin commercial pure Ti foils subjected to uniaxial tensile. The initial microstructure of the annealed Ti foils is fine equiaxed grains, with an average grain size of 3.3 µm. The main types of texture in pure Ti foils are {10 1 ̅ 3} and {11 2 ̅ 4}. Dimples, tear ridges and slip traces are found on the fracture surface, and the elongation reaches 16.7%. The large tensile elongation of pure Ti foils can be attributed to the slip of dislocations, twinning and phase transformation of HCP-Ti to FCC-Ti, which is confirmed by both X-ray diffraction and transmission electron microscope. The orientation relationship of the two phases is determined to be: <0001> HCP // <001> FCC , <11 2 ̅ 0 > HCP // <1 1 ̅ 0 > FCC and {01 1 ̅ 0} HCP // {110} FCC . According to this relationship, the HCP to FCC phase transformation expands the volume of the unit cell by about 10.5%. Furthermore, the volume fraction of FCC-Ti is determined to be about 3.44%. Therefore, the transformation is expected to contribute about 3.6% to the applied strain. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To analyze the links between NFATC1 gene polymorphism and congenital heart disease in children. PATIENTS AND METHODS: In the present study, we selected 85 children patients with congenital heart disease who were hospitalized from February 2013 to February 2015 as research subjects (observation group), and 92 healthy subjects as control group. Restriction fragment length polymorphism (RFLP) was used for analysis of NFATC1 gene in samples from each group. RESULTS: The distribution of NFATC1 genotype and allele between the observation group (children with congenital heart disease) and the control group showed no significant difference (p >0.05), but AA, GG genotypes, and allele frequency between pathological samples of children with congenital heart disease and the control group displayed significant difference (p <0.05) (X2 = 16.04, p <0.05; X2 = 16.29, p <0.05). Further analyses showed that AA, GG, AG genotype and allele frequency among children with congenital heart disease in observation group also showed a difference, i.e., homozygote (AA, GG) ratio in children with severe congenital heart disease is relatively high. CONCLUSIONS: There is a correlation between NFATC1 genes and the incidence of congenital heart disease in children, and a correlation between different genotypes and allele frequency and the incidence of the disease. [ABSTRACT FROM AUTHOR]

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The work presents a detailed investigation of the microstructure characteristics of the γ-fiber (normal direction//<111>) in electron beam melted Ta-2.5W alloy subjected to cold rolling. With increasing strain, the average space of microbands decreases towards a saturation value which is about 0.5 μm. The typical microstructure in γ fiber is microbands and shear bands in different appearance. The microbands are relatively straight and aligned close with slip planes when the strain is lower than 60%. The non-crystallographic irregular microbands and shear bands prevail in γ fiber when the strain is larger than 70%. When the strain reaches 90%, a group of parallel macroshear bands are formed. The orientation of γ fiber can spread up to 60°. Both {111}<112> and {001}<120> new orientations are developed in {111}<110> orientation. Many new developed high angle boundaries of these new grains are coincident site lattice boundaries (Σ3 and Σ9). Meanwhile, these new grains and matrix always share a common <111> or <110> with matrix. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The objective of the present study was to analyze the correlation between GNAS2 gene polymorphisms and children with arrhythmia. PATIENTS AND METHODS: We followed 89 children with arrhythmia treated in our hospital from April 2013 to April 2015, comprising the observation group, while 92 healthy subjects were taken as the control group. We analyzed polymorphisms of the GNAS2 gene from both groups by restriction fragment length polymorphism (RFLP). RESULTS: There were no significant differences (p>0.05) in GNAS2 genotype or allelic distribution between the observation group and control group. However, there were significant differences in the gene frequency of homozygotes (TT and GG) and alleles between the control group and samples from children with arrhythmia (p<0.05) (X2=16.57, p<0.05; X2=17.48, p<0.05). Further study of samples from both groups indicate that gene frequency of homozygous (TT and GG) or heterozygous (TG) genes and alleles also had differences, indicating that homozygotes (TT and GG) are in relatively high proportion among patients with severe cases of arrhythmia. CONCLUSIONS: Morbidity in patients with arrhythmia is related to GNAS2 gene polymorphisms. Differences in genotype and allele frequency are related to the severity of illness. [ABSTRACT FROM AUTHOR]

In order to study the influence of scanning strategy on the printing quality and properties of the formed parts,unidirectional scanning along one axis (X-scan),unidirectional scanning with 90° rotation in each layer (XY-scan),strip partition scanning strategy with direction changes in each layer (S-scan), checkerboard partition scanning strategy with direction changes in each layer (C-scan) were chosen to print 18Ni300 maraging steel by selective laser melting (SLM) process.The effects of different scanning strategies on the surface morphology, relative density,microstructure and mechanical properties of printed parts were studied systematically. The anisotropy of tensile properties of different scanning strategies in different forming directions was analyzed. The results show that the print quality and properties of the partition scanning strategies are better than that of X scanning strategy and XY scanning strategy. The reason is that during the printing process, the partition scanning strategy can divide each layer of laser scanning into multiple areas for printing, which improves the condensing rate for each layer. Compared with X scanning strategy and XY scanning strategy, the scanning direction of the partition scanning strategy changes periodically, which not only helps to fill the bulge and lap gap of the upper layer, but also reduces the heat accumulation and improves the performance of the sample.

Abstract Background SHORT syndrome is a rare genetic disease named with the acronyms of short stature, hyper-extensibility of joints, ocular depression, Rieger anomaly and teething delay. It is inherited in an autosomal dominant manner confirmed by the identification of heterozygous mutations in PIK3R1. This study hereby presents a 15-year-old female with intrauterine growth restriction, short stature, teething delay, characteristic facial gestalts who was identified a novel de novo nonsense mutation in PIK3R1. Case presentation The proband was admitted to our department due to irregular menstrual cycle and hirsutism with short stature, who had a history of intrauterine growth restriction and presented with short stature, teething delay, characteristic facial gestalts, hirsutism, and thyroid disease. Whole-exome sequencing and Sanger sequencing revealed c.1960C > T, a novel de novo nonsense mutation, leading to the termination of protein translation (p. Gln654*). Conclusions This is the first case report of SHORT syndrome complicated with thyroid disease in China, identifying a novel de novo heterozygous nonsense mutation in PIK3R1 gene (p. Gln654*). The phenotypes are mildly different from other cases previously described in the literature, in which our patient presents with lipoatrophy, facial feature, and first reported thyroid disease. Thyroid disease may be a new clinical symptom of patients with SHORT syndrome.

The colonization of microorganisms planted on the surface of teeth and restoration materials is the main cause of oral disease and treatment failure. How to improve the antibacterial properties of dental materials is a hot topic in dentistry. Nano-sized antibacterial materials have attracted much attention. Among them, metal and metal oxide nanoparticles are prominent due to their strong and broad-spectrum antibacterial activity. Thus, in recent years, many studies have used metal and metal oxide nanoparticles to develop antimicrobial dental materials for resin restoration, root canal therapy, orthodontic treatment, and implant surface and removable denture repair and have found that the antibacterial properties of nano-sized materials are significantly enhanced. However, the mechanical properties and esthetic properties of the modified materials are affected, so it is still necessary to explore appropriate modification methods. In addition, most of the experiments are carried out in vitro, which cannot accurately simulate the oral environment. Therefore, the antibacterial effect, cytotoxicity and immune response of these materials in vivo still need further research and exploration. This paper reviewed the potential antibacterial mechanisms and the safety of those nanoparticles and their applications in dentistry.

In recent years, due to precise control of the amorphous mineral precursor in the demineralization of dentine collagen fibers in orderly deposition, forming apatite crystals similar to the natural mineralized dentin, the bottom-up remineralization approach which does not depend on the existence of seed crystallites, dentin biomimetic mineralization techniques gradually become a hotspot in the research field of restoration of demineralized dentin caused by dental caries. This paper reviews the changing concepts and practices of the remineralization of demineralized dentin, emphasizing biomimetic remineralization studies. The results of the literature review show that the traditional dentin remineralization method is usually a disordered mixture of demineralized dentin and minerals, so mineralized dentin is not comparable to natural mineralized dentin in terms of the morphological characteristics and mechanical properties. With its gradual increase in recent years, dentine biomimetic mineralization technology perfectly resembles the minerals in the dentin overlapping sequence arranged with the dentine collagen fiber structure characteristics, leading to greatly improved microstructural, physical and chemical properties. As a result, dentine biomimetic mineralization technology is expected to achieve new breakthroughs in the fields of resin-dentin bonding mixing layers and the decay of dentin. At present, the technical obstacles that need to be overcome in the clinical application of the biomimetic remineralization of dentin are how to continuously supplement all the active ingredients needed for mineralization in the process of remineralization and how to keep the mechanical properties of the parent material unchanged while slowly releasing all ingredients. Researchers have successively proposed three-step transportation of the biomimetic remineralization of raw materials, as well as the preparation of mineralization precursors stabilized by polymers in advance and the reuse of mesoporous silicon nanomaterials for the transportation of the mineralized ingredient system. The concept described above provides the preliminary in vitro experimental basis for the transformation of the biomimetic remineralization strategy of dentin in clinical applications.

In view of the limitation of wide application of polypropylene(PP) with low strength, poor low-temperature brittleness and easy combustion, a kind of PP matrix nanocomposites was designed and prepared. Sb2O3 nanoparticles (nano-Sb2O3) modified by silane coupling agent of KH550 were dispersed into brominated polystyrene(BPS)-PP matrix by ball milling dispersion and melt blending method, respectively. And the nano-Sb2O3/BPS-PP composites samples were obtained by injection molding method. The effects of nano-Sb2O3 particles on mechanical properties of nano-Sb2O3/BPS-PP composites were investigated. The results showed that the surface of nano-Sb2O3 particles was successfully modified by the KH550 and the interfacial adhesion between nano-Sb2O3 and PP matrix was improved. With increasing of the mass fraction of nano-Sb2O3, the tensile strength and impact strength of nano-Sb2O3/BPS-PP composites were improved accompanying by increasing of crystallinity and refining grain of the composites. When the mass fraction of nano-Sb2O3 was 3 wt%, the tensile strength of nano-Sb2O3/BPS-PP composites was 43 MPa, which was 30.3% higher than that of PP. When the mass fraction of nano-Sb2O3 was 2 wt%, the impact strength of the composites was 44.19 kJ·m−2, which was 30.8% higher than that of PP.

This paper examines and discusses the dynamic response of a high-speed train-bridge-soil-pile foundation system to near-fault earthquakes. A 72 + 120 + 72 m continuous girder bridge of a high-speed railroad was selected as the model for calculation. Based on the p-y model for simulating pile-soil interaction, the moment-curvature analysis program XTRACT is used to calculate the moment and curvature of bridge piers and pile foundation sections, and the finite element (FE) software is used to establish two nonlinear global bridge models under seismic effects in the high-intensity zone, one considering pile-soil interaction and one without considering pile-soil interaction. The Ap/Vp parameter, the ratio of peak acceleration to peak velocity of transverse ground shaking, is used to reflect the impulse characteristics of earthquakes and the effect of the Ap/Vp parameter on the dynamic response of bridges to earthquakes was studied. The elastic-plastic response of the bridge system was calculated under lateral and vertical near-fault (NF) impulse/NF nonimpulse/far-field (FF) ground motions (GMs). The study shows that the structural displacement increases, and the internal force decreases after considering the pile-soil interaction. The results show that the bridge piers enter the elastoplastic phase under rare earthquakes. The NF ground shaking couples with the bridge into the elastoplastic phase with a more significant impulse period than the FF ground shaking intensifies the dynamic response of the bridge structure.

We develop a novel approach to measure the dust attenuation properties of galaxies, including the dust opacity, the shape of the attenuation curve, and the strength of the 2175 Å absorption feature. From an observed spectrum, the method uses a model-independent approach to derive a relative attenuation curve with an absolute amplitude calibrated using NIR photometry. The dust-corrected spectrum is fitted with stellar population models to derive the dust-free model spectrum, which is compared with the observed SED/spectrum from NUV to NIR to determine the dust attenuation properties. We apply this method to investigate dust attenuation on kiloparsec scales using a sample of 134 galaxies with integral field spectroscopy from MaNGA, NIR imaging from 2MASS, and NUV imaging from Swift/UVOT. We find that the attenuation curve slope and the 2175 Å bump in both the optical and NUV span a wide range at kiloparsec scales. The slope is shallower at higher optical opacity, regardless of the specific star formation rate (sSFR), the minor-to-major axis ratio ( b / a ) of the galaxies, and the location of spaxels within individual galaxies. The 2175 Å bump presents a strong negative correlation with the sSFR, while the correlations with the optical opacity, b / a , and the locations within individual galaxies are all weak. All of these trends appear to be independent of the stellar mass of the galaxies. Our results support the scenario that the variation of the 2175 Å bump is driven predominantly by processes related to star formation, such as the destruction of small dust grains by UV radiation in star-forming regions.

Vitamin D is an essential nutrient in the body. In recent years, increasing attention has been paid to its role in regulating immunity and anti-inflammatory effects. However, the application of vitamin D in vivo may produce some side effects, such as hypercalcemia and hypercalciuria. Some analogs of vitamin D obtained through molecular modification can reduce the side effects while retaining a similar regulatory action as that of vitamin D. The supplementation of vitamin D or the use of vitamin D analogs may contribute to the prevention and treatment of immune inflammatory diseases. This article reviews the role of vitamin D and its analogues in the prevention and treatment of oral mucosal diseases and periodontal diseases. The literature review results show that vitamin D and its analogues can protect the integrity of the oral mucosal barrier, prevent or delay the occurrence of oral lichen planus, and provide a reference value for the prevention and treatment of periodontitis.

Childhood epilepsy is a considerably heterogeneous neurological condition with a high worldwide incidence. Genetic diagnosis of childhood epilepsy provides the most accurate pathogenetic evidence; however, a large proportion of highly suspected cases remain undiagnosed. Accumulation of rare variants at the exome level as a multigenic burden contributing to childhood epilepsy should be further evaluated. In this retrospective analysis, exome-level sequencing was used to depict the mutation spectra of 294 childhood epilepsy patients from Shanghai Children’s Medical Center, Department of Neurology. Furthermore, variant information from exome sequencing data was analyzed apart from monogenic diagnostic purposes to elucidate the possible multigenic burden of rare variants related to epilepsy pathogenesis. Exome sequencing reached a diagnostic rate of 30.61% and identified six genes not currently listed in the epilepsy-associated gene list. A multigenic burden study revealed a three-fold possibility that deleterious missense mutations in ion channel and synaptic genes in the undiagnosed cohort may contribute to the genetic risk of childhood epilepsy, whereas variants in the gene categories of cell growth, metabolic, and regulatory function showed no significant difference. Our study provides a comprehensive overview of the genetic diagnosis of a Chinese childhood epilepsy cohort and provides novel insights into the genetic background of these patients. Harmful missense mutations in genes related to ion channels and synapses are most likely to produce a multigenic burden in childhood epilepsy.

Methane seeps are chemosynthetic ecosystems in the deep-sea environment. Microbial community structures have been extensively studied in the seepage-affected sediments and investigation in the water column above the seeping sites is still lacking. In this study, prokaryotic communities in the bottom water about 50 cm from the seabed at methane seeps with various seepage intensities in Haima, South China Sea were comparatively studied by using 16S ribosomal RNA gene sequencing. These sites were assigned based on their distinct methane content levels and seafloor landscapes as the non-seepage (NS) site, low-intensity seepage (LIS) site, and high-intensity seepage (HIS) site. The abundances of the dominant phyla Proteobacteria, Bacteroidetes, and Actinobacteria differed significantly between NS and the two seepage sites (p < 0.05). Alpha diversity differed among the three sites with the HIS site showing the lowest community diversity. Principal component analysis revealed highly divergent bacterial community structures at three sites. Many environmental variables including temperature, alkalinity, pH, methane, dissolved organic carbon (DOC), and inorganic nutrients were measured. Redundancy analysis indicated that methane content is the key environmental factor driving bacterial community variation (p = 0.001). Linear discriminant analysis effect size analysis identified various differentially enriched genera at the LIS and HIS sites. Phylogenetic analysis revealed close phylogenetic relationship among the operational taxonomic units of these genera with known oil-degrading species, indicating oil seepage may occur at the Haima cold seeps. Co-occurrence networks indicated that the strength of microbial interactions was weakest at the HIS site. This study represents a comprehensive comparison of microbial profiles in the water column of cold seeps in the SCS, revealing that the seepage intensity has a strong impact on bacterial community dynamics.

Abstract Background Osteopetrosis is characterized by increased bone density and bone marrow cavity stenosis due to a decrease in the number of osteoclasts or the dysfunction of their differentiation and absorption properties usually caused by biallelic variants of the TCIRG1 and CLCN7 genes. Methods In this study, we describe five Chinese children who presented with anemia, thrombocytopenia, hepatosplenomegaly, repeated infections, and increased bone density. Whole‐exome sequencing identified five compound heterozygous variants of the CLCN7 and TCIRG1 genes in these patients. Results Patient 1 had a novel variant c.1555C>T (p.L519F) and a previously reported pathogenic variant c.2299C>T (p.R767W) in CLCN7. Patient 2 harbored a novel missense variant (c.1025T>C; p.L342P) and a novel splicing variant (c.286‐9G>A) in CLCN7. Patients 3A and 3B from one family displayed the same compound heterozygous TCIRG1 variant, including a novel frameshift variant (c.1370del; p.T457Tfs*71) and a novel splicing variant (c.1554+2T>C). In Patient 4, two novel variants were identified in the TCIRG1 gene: c.676G>T; p.E226* and c.1191del; p.P398Sfs*5. Patient 5 harbored two known pathogenic variants, c.909C>A (p.Y303*) and c.2008C>T (p.R670*), in TCIRG1. Analysis of the products obtained from the reverse transcription‐polymerase chain reaction revealed that the c.286‐9G>A variant in CLCN7 of patient 2 leads to intron 3 retention, resulting in the formation of a premature termination codon (p.E95Vfs*8). These five patients were eventually diagnosed with autosomal recessive osteopetrosis, and the three children with TCIRG1 variants received hematopoietic stem cell transplantation. Conclusions Our results expand the spectrum of variation of genes related to osteopetrosis and deepen the understanding of the relationship between the genotype and clinical characteristics of osteopetrosis.