Present-day movement characteristics of the Qinghai Nanshan fault and its surrounding area from GPS observation

The Qinghai Nanshan fault is a larger fault in the Northeastern Xizang Plateau.In previous studies,its movement characteristics are mainly investigated with geological and seismic observations,and the tectonic transformation role of the fault on its east is not yet clear.This study uses data fusion to obtain denser GPS observations near the Qinghai Nanshan fault.Based on tectonic characteristics,we establish a block model to investigate the fault slip rate,locking degree,and slip deficit.The results show that the Qinghai Nanshan fault slip rate is characterized by sinistral and convergent movement.Both the sinistral and convergent rates display a decreasing trend from west to east.The locking degree and slip deficit are higher in the western segment(with an average of about 0.74 and 1.1 mm/a)and lower in the eastern segment.Then,we construct a strain rate field using GPS observations to analyze the regional strain characteristics.The results indicate that along the fault,the western segment shows a larger shear strain rate and negative dilation rate.Regional earthquake records show that the frequency of earthquakes is lower near the fault.The joint results suggest that the western segment may have a higher earthquake risk.In addition,the insignificant fault slip rate in the eastern segment may indicate that it does not participate in the tectonic transformation among the Riyueshan,Lajishan,and West Qinling faults.

Development of biofertilizers for sustainable agriculture over four decades(1980-2022)

The application of biofertilizers is becoming an inevitable trend to substitute chemical fertilizers for sustainable agriculture.To better understand the development of biofertilizers from 1980 to 2022,we used bibliometric mining to analyze 12,880 journal articles related to biofertilizer.The network cooccurrence analysis suggested that the biofertilizers research can be separated into three stages.The first stage(1980-2005)focused on nitrogen fixation.The second stage(2006-2015)concentrated on the mechanisms for increasing plant yield.The third stage(2016-2022)was the application of biofertilizers to improve the soil environment.The keyword analysis revealed the mechanisms of biofertilizers to improve plant-growth:biofertilizers can impact the nutritional status of plants,regulate plant hormones,and improve soil environments and the microbiome.The bacteria use as biofertilizers,included Pseudomonas,Azospirillum,and Bacillus,were also identified through bibliometric mining.These findings provide critical discernment to aid further study of biofertilizers for sustainable agriculture.

Effect of sinomenine stellate ganglion block on chronic myocardial ischemia in rats

Objective:To investigate the protective effect of sinomenine stellate ganglion block(SGB)on chronic myocardial ischemia and its related mechanism.Methods:SD male and female rats(180~200g)were randomly divided into four groups:blank group,model group,lidocaine group,lidocaine+sinomenine group.The rats in blank group were fed with normal standard diet without modeling,and the other rats were fed with high-fat diet.After 8 weeks of feeding,the rats in high-fat diet group were significantly different from those in blank control group.Then they were randomly divided into 3 groups,10 rats in model group were injected with 0.9%NaCl into right stellate ganglion(RSG)After 2 weeks of continuous injection,pituitrin injection was continuously injected into sublingual vein of rats for 3 days,once every 24 hours;lidocaine group rats were injected with 0.24 mL 1%lidocaine injection in RSG,the rest was the same as model group;lidocaine+sinomenine group rats were injected with 0.24 mL 1%lidocaine injection+0.095 mL sinomenine hydrochloride+2.9 mL 0.8 mL 0.8 mL in RSG,the rest was the same as model group.At the end of the eighth week of the experiment,the rats in the high-fat diet feeding group and the standard ordinary diet feeding group were given the medicine after there was significant difference in blood lipid;before the third injection of pituitrin,the ECG changes of the rats in each group were observed;the general situation of the rats before and after the administration was observed;after the experiment,the blood of the rats in each group was taken from the abdominal aorta,and the serum oxidative stress indexes,such as total superoxide dismutase(SOD)and malondialdehyde,were detected(MDA,IL-6 and cTnI were measured.Results:compared with the blank group,the ECG of the model group changed significantly(P<0.01),the cTnI value increased significantly(P<0.01),indicating that the rat myocardial ischemia model was successfully established;compared with the model group,the SOD level of lidocaine group and lidocaine+sinomenine group increased significantly(P<0.05,P<0.01),the MDA level decreased significantly(P<0.05,P<0.01),IL-6 decreased significantly(P<0.05,P<0.01)05,P<0.01).Conclusion:sinomenine SGB has protective effect on rats with chronic myocardial ischemia,which is related to anti oxidative stress and inhibition of inflammatory reaction.

单中心催化剂及其聚烯烃材料的研发进展

聚烯烃是一种使用量最大、应用最广,并且生产过程能耗和污染很小的高分子材料,在汽车、包装、建筑、电器、医疗等领域应用十分广泛。随着我国深化供给侧结构性改革,构建国内国际相互促进的新发展格局的推进,解决高端产品自主可控,实现通用产品高质量发展已成为必然趋势。单中心催化剂及其聚合物产品研发,极大丰富了聚烯烃产品种类,拓展了聚烯烃产品的应用领域。文中概述了单中心催化剂体系组成、各类单中心催化剂的特点及高通量技术在单活性中心催化剂研发中的应用情况,详细介绍了各类主流单中心聚烯烃材料的特点及应用进展,并提出了未来我国单中心催化剂及其产品工业化发展方向。

留学生与近代中国教育经济学的萌生

留学生是近代中国教育经济学萌生的奠基者和开拓者。他们对教育经济问题的研究,既适应了近代教育事业发展的需要,也符合教育学科发展的趋势。留学生以教育与经济的相互关系、作用及规律为研究对象;研究内容涉及教育经费的筹集分配与使用、教育财政、教育投入与产出等方面;研究方法以实证方法为主。在留学生群体的努力下,近代中国教育经济学的萌生呈现出主体化、科学化、本土化的特点。留学生对教育经济问题的探讨,促进了近代教育事业的发展,推动了中国教育经济学的产生,也为当前构建中国特色教育经济学提供了可资借鉴的历史经验及有益启示。

Treatment of nutcracker syndrome with spermatic vein ligation and iliac vein anastomosis:Case report of three cases

Three patients with nutcracker syndrome(NCS) were enrolled in the study.Their clinical symptoms mainly included proteinuria and serious varicocele.Color Doppler ultrasound and computed tomography showed that the patients had constricted abdominal aortas,reduced superior mesenteric artery angles,and thinned left renal veins.Patients then underwent left spermatic vein ligation and iliac vein anastomosis.They were checked tliree months after their operation,and results showed that their sperms were improved and their proteinuria disappeared. The color Doppler ultrasound showed new cycle pathways.NCS clinical manifestations are complicated,and need combination diagnosis of symptoms and auxiliary examination to detennine surgical indications.Ligation of spermatic vein and vein anastomosis can be used to treat NCS.

Laboratory model study of newly deposited dredger fills using improved multiple-vacuum preloading technique

Problems continue to be encountered concerning the traditional vacuum preloading method in field during the treatment of newly deposited dredger fills.In this paper,an improved multiple-vacuum preloading method was developed to consolidate newly dredger fills that are hydraulically placed in seawater for land reclamation in Lingang Industrial Zone of Tianjin City,China.With this multiplevacuum preloading method,the newly deposited dredger fills could be treated effectively by adopting a novel moisture separator and a rapid improvement technique without sand cushion.A series of model tests was conducted in the laboratory for comparing the results from the multiple-vacuum preloading method and the traditional one.Ten piezometers and settlement plates were installed to measure the variations in excess pore water pressures and moisture content,and vane shear strength was measured at different positions.The testing results indicate that water dischargeetime curves obtained by the traditional vacuum preloading method can be divided into three phases:rapid growth phase,slow growth phase,and steady phase.According to the process of fluid flow concentrated along tiny ripples and building of larger channels inside soils during the whole vacuum loading process,the fluctuations of pore water pressure during each loading step are divided into three phases:steady phase,rapid dissipation phase,and slow dissipation phase.An optimal loading pattern which could have a best treatment effect was proposed for calculating the water discharge and pore water pressure of soil using the improved multiple-vacuum preloading method.For the newly deposited dredger fills at Lingang Industrial Zone of Tianjin City,the best loading step was 20 kPa and the loading of 40-50 k Pa produced the highest drainage consolidation.The measured moisture content and vane shear strength were discussed in terms of the effect of reinforcement,both of which indicate that the multiple-vacuum preloading method has a better treatment effect not only in decreasing the moisture content and increasing the bearing capacity,but also in increasing the process uniformity at different depths of foundation.

Assessing the deformation response of double-track overlapped tunnels using numerical simulation and field monitoring

The unprecedented rate of metro construction has led to a highly complex network of metro lines.Tunnels are being overlapped to an ever-increasing degree.This paper investigates the deformation response of double-track overlapped tunnels in Tianjin,China using finite element analysis(FEA)and field monitoring,considering the attributes of different tunneling forms.With respect to the upper tunneling,the results of the FEA and field monitoring showed that the maximum vertical displacements of the ground surface during the tail passage were 2.06 mm,2.25 mm and 2.39 mm obtained by the FEA,field monitoring and Peck calculation,respectively;the heaves on the vertical displacement curve were observed at 8 m(1.25D,where D is the diameter of the tunnel)away from the center of the tunnel and the curve at both sides was asymmetrical.Furthermore,the crown and bottom produce approximately0.38 mm and 1.26 mm of contraction,respectively.The results of the FEA of the upper and lower sections demonstrated that the tunneling form has an obvious influence on the deformation response of the double-track overlapped tunnel.Compared with the upper tunneling,the lower tunneling exerted significantly less influence on the deformation response,which manifested as a smaller displacement of the strata and deformation of the existing tunnel.The results of this study on overlapped tunnels can provide a reference for similar projects in the future.

Plasticity of language pathways in patients with low-grade glioma A diffusion tensor imaging study

Knowledge of the plasticity of language pathways neurosurgeons to achieve maximum resection wh n patients with low-grade glioma is important for e preserving neurological function. The current study sought to investigate changes in the ventral language pathways in patients with low-grade glioma located in regions likely to affect the dorsal language pathways. The results revealed no significant difference in fractional anisotropy values in the arcuate fasciculus between groups or between hemispheres. However, fractional anisotropy and lateralization index values in the left inferior longitudinal fasciculus and lateralization index values in the left inferior fronto-occpital fasciculus were higher in patients than in healthy subjects. These results indicate plasticity of language pathways in patients with low-grade glioma. The ventral language pathways may perform more functions in patients than in healthy subjects. As such, it is important to protect the ventral language pathways intraoperatively.

Prospective study found that peripheral lymph node sampling reduced the false-negative rate of sentinel lymph node biopsy for breast cancer

Background:Although sentinel lymph node biopsy(SLNB) can accurately predict the status of axillary lymph node(ALN) metastasis,the high false?negative rate(FNR) of SLNB is still the main obstacle for the treatment of patients who receive SLNB instead of ALN dissection(ALND).The purpose of this study was to evaluate the clinical significance of SLNB combined with peripheral lymph node(PLN) sampling for reducing the FNR for breast cancer and to discuss the effect of "skip metastasis" on the FNR of SLNB.Methods:At Shandong Cancer Hospital Affiliated to Shandong University between March 1,2012 and June 30,2015,the sentinel lymph nodes(SLNs) of 596 patients with breast cancer were examined using radiocolloids with blue dye tracer.First,the SLNs were removed;then,the area surrounding the original SLNs was selected,and the visible lymph nodes in a field of 3–5 cm in diameter around the center(i.e.,PLNs) were removed,avoiding damage to the structure of the breast.Finally,ALND was performed.The SLNs,PLNs,and remaining ALNs underwent pathologic examination,and the relationship between them was analyzed.Results:The identification rate of SLNs in the 596 patients was 95.1%(567/596);the metastasis rate of ALNs was 33.7%(191/567);the FNR of pure SLNB was 9.9%(19/191);and after the SLNs and PLNs were eliminated,the FNR was 4.2%(8/191),which was significantly decreased compared with the FNR before removal of PLNs(P Aected number(N) of SLNs,the patients were divided into four groups of N = 0.028).ccording to the det= 1,2,3,and ≥4;the FNR in these groups was 19.6,9.8,7.3,and 2.3%,respectively.For the patients with removal of PLNs was significantly decreased compared with that before remo≤2 or val of P≤3 detected SLNs,the FNR afterLNs(N 3:12.2% vs.4.7%,P ≤ 2:14.0% vs.4.7%,P = 0.019;N ≤ nt(P = 0.021),whereas for patients with ≥4 detected SLNs,the decrease in FNR was not statistically significa= 1.000).In the entire cohorts,the "skip metastasis" rate was 2.5%(15/596);the FNR caused by "skip metastasis" was 2.1%(4/191).Conclusions:The FNR of SLNB was associated with the number of SLNs.For patients with mpling can reduce the FNR of SLNB to an acceptable level of less than 5%.Because of the≤3 detected SLNs,PLN sa existence of the "skip metastasis" and distinct metastasis patterns,the FNR of SLNB cannot be completely eliminated.

Automated classification of dual channel dental imaging of auto-fluorescence and white lightby convolutional neural networks

Prevention is the most effective way to reduce dental caries.In order to provide a simple way to achieve oral healthcare direction in daily life,dual Channel,portable dental Imaging system that combine white light with autofluorescence techniques was established,and then,a group of volunteers were recruited,7200 tooth pictures of different dental caries stage and dental plaque were taken and collected.In this work,a customized Convolutional Neural Networks(CNNs)have been designed to classify dental image with early stage caries and dental plaque.Eighty percentage(n=6000)of the pictures taken were used to supervised training of the CNNs based on the experienced dentists'advice and the rest 20%(n=1200)were used to a test dataset to test the trained CNNs.The accuracy,sensitivity and specificity were calculated to evaluate perfor-mance of the CNNs.The accuracy for the early stage caries and dental plaque were 95.3%and 95.9%,respectively.These results shown that the designed image system combined the cus-tomized CNNs that could automatically and efficiently find early caries and dental plaque on occlusal,lingual and buccal surfaces.Therefore,this will provide a novel approach to dental caries prevention for everyone in daily life.

Application of medial column classification in treatment of intraarticular calcaneal fractures

BACKGROUND There are many types of treatments for calcaneal fractures,including conservative treatment,conventional surgical treatment,and minimally invasive surgery.The choice of specific treatment options is still controversial.Open reduction and internal fixation are currently the most commonly used surgical procedures in the clinic.A good fracture reduction effect can be achieved by using the lateral extension incision of the calcaneus;however,many studies have reported a high incidence of postoperative incision complications.Although there are many methods for the classification of intra-articular calcaneal fractures,it is generally believed that the computed tomography(CT)classification proposed by Sanders has high application value in the selection of treatment methods and evaluation of prognosis of calcaneal fractures.However,this method has no clear guiding significance for the choice of surgical incision and surgical plan.AIM To explore the application and clinical efficacy of medial column classification in the treatment of intra-articular calcaneal fractures.METHODS From July 2017 to July 2018,91 patients,including 60 males and 31 females aged 27 to 60 years,were enrolled.All participants had closed intra-articular calcaneal fracture,and their surgical options were selected under the guidance of medial column classification.The patients'fractures were classified according to the Sanders classification:Type II,35 cases;Type III,33 cases;and Type IV,23 cases.Among them,53 patients had medial column displacement(shortened varus)and underwent open reduction and internal fixation with L-lateral incision of the calcaneus;38 patients had no displacement of the medial column and underwent open reduction and internal fixation with tarsal sinus incision.The calcaneus Bohler angle,Gissane angle,length,width,height,and step thickness of the articular surface were evaluated by X-ray and three-dimensional CT before and after surgery and at the last follow-up.Foot function recovery was assessed by the Maryland foot scoring criteria.RESULTS All patients were followed for 5 to 14 mo,with an average of 10.5±2.9 mo.The fractures of all patients healed,and the healing time was 10 to 19 wk,with an average of 10.8±1.5 wk.One patient developed wound infection 1 wk after surgery and was actively debrided and implanted with antibiotic calcium sulfate to control the infection.The patient's fracture healed 5 mo after surgery.One patient developed a sural nerve injury,and the symptoms disappeared 3 mo after surgery.The patients were assessed according to the Maryland foot scoring system:Excellent in 77 cases,good in 10,and fair in 4.The excellent and good rate was 95.6%.CONCLUSION Medial column classification can effectively guide the surgical selection for intraarticular fractures of the calcaneus.

Intraoperative diffusion tensor imaging predicts the recovery of motor dysfunction after insular lesions

Insular lesions remain surgically challenging because of the need to balance aggressive resection and functional protection. Motor function deficits due to corticospinal tract injury are a common complication of surgery for lesions adjacent to the internal capsule and it is therefore essential to evaluate the corticospinal tract adjacent to the lesion. We used diffusion tensor imaging to evaluate the corticospinal tract in 89 patients with insular lobe lesions who underwent surgery in Chinese PLA General Hospital from February 2009 to May 2011. Postoperative motor function evaluation revealed that 57 patients had no changes in motor function, and 32 patients suffered motor dysfunction or aggravated motor dysfunction. Of the affected patients, 20 recovered motor function during the 6-12-month follow-up, and an additional 12 patients did not recover over more than 12 months of follow-up. Following reconstruction of the corticospinal tract, fractional anisotropy comparison demonstrated that preoperative, intraoperative and follow-up normalized fractional anisotropy in the stable group was higher than in the transient deficits group or the long-term deficits group. Compared with the transient deficits group, intraoperative normalized fractional anisotropy significantly decreased in the long-term deficits group. We conclude that intraoperative fractional anisotropy values of the corticospinal tracts can be used as a prognostic indicator of motor function outcome.

Stomach wall structure and vessels imaging by acoustic resolution photoacoustic microscopy

AIM To image stomach wall blood vessels and tissue, layerby-layer.METHODS We built up the acoustic resolution photoacoustic microscopy(AR-PAM) system for imaging layered tissues, such as the stomach wall. A tunable dye laser system was coupled to a fiber bundle. The fibers of the bundle were placed in nine directions with an incident angle of 45° around a high-frequency ultrasound transducer attached to the acoustic lens. This structure formed a dark field on the tissue surface under the acoustic lens and the nine light beams from the fibers to be combined near the focal point of the acoustic lens. The sample piece was cut from a part of the porcine stomach into a petri dish. In order to realize photoacoustic depth imaging of tumor, we designed a tumor model based on indocyanine green(ICG) dye. The ICG solution(concentration of 129 μM/m L)was mixed into molten gel, and then a gel mixture of ICG(concentration of 12.9 μM/mL) was injected into the stomach submucosa. The injection quantity was controlled by 0.1 mL to make a small tumor model. RESULTS An acoustic resolution photoacoustic microscopy based on fiber illumination was established and an axial resolution of 25 μm and a lateral resolution of 50 μm in its focal zone range of 500 μm has been accomplished. We tuned the laser wavelength to 600 nm. The photoacoustic probe was driven to do B-scan imaging in tissue thickness of 200 μm. The photoacoustic micro-image of mucosa and submucosa of the tissue have been obtained and compared with a pathological photograph of the tissue stained by hematoxylin-eosin staining. We have observed more detailed internal structure of the tissue. We also utilized this photoacoustic microscopy to image blood vessels inside the submucosa. High contrast imaging of the submucosa tumor model was obtained using ICG dye. CONCLUSION This AR-PAM is able to image layer-by-layer construction and some blood vessels under mucosa in the stomach wall without any contrast agents.

Ground movement induced by triple stacked tunneling with different construction sequences

This study tried to explore the ground movement induced by triple stacked tunneling(TST) with different construction sequences. A case study in Tianjin, China was used to investigate the ground movement during the TST(upper tunneling(UT)). For this, a modified Peck formula was proposed to predict the surface settlement induced by TST. Next, three sets of finite element analyses(FEA) were used to compare the effects of construction sequences(i.e. UT, middle tunneling(MT), and lower tunneling(LT)) on vertical and lateral ground displacements. The results of Tianjin case and UT reveal that compared to a Gaussian distribution for a single tunnel, the surface settlement curve of triple stacked tunnels is a bimodal distribution. It seems that the proposed modified Peck formula can effectively predict the surface settlement induced by TST. The results of the three sets of FEA demonstrate that the construction sequence has a significant influence on the ground movement. Among the three construction sequences, the largest lateral displacement is observed in the MT and the smallest one in UT.The existing tunnel has an inhibitory effect on the vertical displacement. The maximum value of the lateral displacement occurs at the depth of the new tunnel in each construction sequence.

Magnetic resonance diffusion tensor imaging-based evaluation of optic-radiation shape and position in meningioma

Employing magnetic resonance diffusion tensor imaging, three-dimensional white-matter imaging and conventional magnetic resonance imaging can demonstrate the tumor parenchyma, peritumoral edema and compression on surrounding brain tissue. A color-coded tensor map and three-dimensional tracer diagram were applied to clearly display the optic-radiation location, course and damage. Results showed that the altered anisotropy values of meningioma patients corresponded with optic-radiation shape, size and position on both sides. Experimental findings indicate that the magnetic resonance diffusion tensor imaging technique is a means of tracing and clearly visualizing the optic radiation.

QUANTIFYING NANOP ARTICLE TRANSPORT IN VIVO USING HYP ERSPECTRAL IMA GING WITH A DORSAL SKINFOLD WINDOW CHAMBER

We have developed a noninv asive imaging method to quantify in viwo drug delivery pharmaco-kinetics without the need for blood or tissue collection to determine drug concentration.By combining the techniques of hy perspectral imaging and a dorsal skinfold window chamber,this method enabled the real-time monitoring of vascular transport and tissue deposition of nano-particles labeled with near infrared(NIR)dye.Using this imaging method,we quantified the delivery pharmacokinetics of the native high-density lipoprotein(HDL)and epidermal growth factor receptor(EGFR)-targeted HDL nanoparticles and demonstrated these HDLs had long circulation time in blood stream(half-life>12h).These HDL nanoparticles could eficiently carry cargo DiR-BOA to extravasate from blood vesels,difuse through extr acellular matrix,and penetrate and be retained in the tumor site.The EGFR targeting specificity of EGFR-targeted HDL(EGFR-specific peptide conjugated HDL)was also visualized in vivo by competitive inhi bition with excess EGFR specifc peptide.In summary,this imaging technology may help point the way toward the development of novel imaging based pharmacokinetic assays for preclinical drugs and evaluation of drug delivery eficiency,providing a dynamic window into the devel opment and application of novel drug delivery systems.

ACTIVATABLE SMART PROBES FOR MOLECULAR OPTICAL IMAGING AND THERAPY

Recent years have seen the design and implementation of many optical activatable smart probes.These probes are activatable because they change their optical properties and are smart because they can identify specific targets.This broad class of detection agents has allowed previously unperformed visualizations,facilitating the study of diverse biomolecules including enzymes,nucleic acids,ions and reactive oxygen species.Designed to be robust in an in vivo environment,these probes have been used in tissue culture cells and in live small animals.An emerging class of smart probes has been designed to harness the potency of singlet oxygen generating photosensitizers.Combining the discrimination of activatable agents with the toxicity of photosensitizers represents a new and powerful approach to disease treatment.This review highlights some applications of activatable smart probes with a focus on developments of the past decade.

Measurement of Optical Fiber Geometry Parameters with Bessel Function Fitting Method

Geometry parameters of optical fiber are crucial in evaluating the quality of the optical fiber.Near⁃field light distribution method is recommended in GB15972.20-2008 for the measurement of geometry parameters.To distinguish the boundary between fiber core and cladding,it is necessary to illuminate the fiber.The end face of the core is a bright spot with unclear edge,so the true edge of the core and the cladding cannot be accurately judged.A method is proposed in this paper to measure the geometry parameters of optical fiber by Bessel function fitting.Theoretically,the solution to the electromagnetic vector of mode field satisfies Bessel function,and the boundary between the core and the cladding can be precisely extracted by Bessel function fitting.Edges of the fiber were fitted by elliptical curves,and the geometry parameters of the fibers could be calculated.Results show that the maximum deviations of the diameters and the average differences of the fibers were decreased under normal and abnormal conditions respectively.The proposed method is an efficient way to obtain edge data and can improve the accuracy and stability of geometry parameters of optical fibers.

A Routing Strategy with Link Disruption Tolerance for Multilayered Satellite Networks

Link disruption has a considerable impact on routing in multilayered satellite networks, which includes predictable disruption from the periodic satellite motion and unpredictable disruption from communication faults. Based on the analysis on the predictability of satellite links, a link disruption routing strategy is proposed for multilayered satellite networks, where, a topology period is divided into non-uniform slots, and a routing table in each slot is calculated by the topology predictability of satellite networks, and a congestion control mechanism is proposed to ensure the reliable transmission of packets, and a flooding mechanism is given to deal with the routes selection in the case of unpredictable link disruption. This routing strategy is implemented on the satellite network simulation platform, the simulation results show that the strategy has less delay and higher link utilization, and can meet the routing requirements of multilayered satellite networks.