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Background: Brucellosis is a zoonotic infectious disease. Neurobrucellosis occurs when Borrelia burgdorferi infects the nervous system and is a complication of brucellosis. Infection is a common post-cranioplasty complication, although co-infection with B. burgdorferi is rare. In this article, we report a case of neurobrucellosis caused by B. burgdorferi infection after cranioplasty in a female patient with traumatic brain injury and review the literature. Case Description: A 37-year-old woman with traumatic brain injury underwent emergency clot removal and decompression craniectomy. Three-dimensional titanium mesh cranioplasty was performed 4 years later. Unfortunately, only 1 year later, the skull repair material had to be removed because of a localized scalp infection in the area of the skull repair. Cranioplasty was performed 5 months later with polyetheretherketone material. The patient remained free of symptoms until July 27, 2022, when the patient was readmitted for a headache. The final diagnosis of neurobrucellosis was made after relevant examinations, tests, and subcutaneous puncture of aspirated pus for bacterial cultures and special genus tests. Following the standard protocol, the patient was treated effectively. Conclusion: Neurobrucellosis occurs after a patient contracts a neurological infection through contact with the excrement of an infected animal or ingestion of food from an infected or diseased animal. Any postoperative complications of specific infections can cause physical pain and a heavy financial burden on the patient because of the special and expensive materials used for cranial repair. Therefore, we recommend screening patients from areas at epidemiological risk for relevant diseases before undergoing cranioplasty.

Water is the most abundant molecule found on the earth's surface and is a key factor in multiscale rock destruction. However, given the fine-grained nature of rock and the complexity of its internal structure, the microstructural evolution of rock under the action of water has not yet been elucidated in detail, and little is understood about the relationship between the rock structure and solid–liquid unit. A variety of techniques were used in this study to track the mechanical properties, pore and crack characteristics, and mineral structure degradation characteristics of sandstone at different stages under the action of deionized water, and the evolution mechanisms of the microstructure were analyzed at the molecular scale. The results showed that during the water–rock interaction process, water was adsorbed onto the surface of dolomite minerals and the hydrophilic surface of clay minerals, forming a high-density hydrogen bond network. However, different mineral surface structures had different water adsorption structures, resulting in the strain of the dense clay mineral aggregates under expansion action. Stress concentrated at crack tips under the capillary force of dolomite minerals (very weak dolomite dissolution). These effects resulted in a substantial increase in the number of small pores and enhancements in pore–crack connectivity, and the rock strength exhibited varying degrees of decline at different stages of wet-dry cycles. In general, the results of this paper will help to further elucidate the internal connections between molecular-scale and macroscale processes in rock science.

Microfocus X-ray CT scanning (μCT) is one of the most effective methods for visualization of pore-fracture structure in rock, and its effectiveness in 3d imaging of pore-fracture in tight sandstone should be further explored.Taking the tight sandstone at the dam site of Baihetan Hydropower Station as an example, the pore-fracture 3D imaging characteristics of samples with different scanning accuracy were explored by using ultra-high precision μCT technology and segmentation algorithm, and their influence on obtaining key structural information was analyzed by SEM test.The results show that the combined segmentation method of interactive threshold and Top-hat can extract the pore and fracture information of tight sandstone more accurately. The interactive threshold segmentation method is suitable for the extraction of large pore and fracture, and the Top-hat segmentation method is suitable for the extraction of small pore.Small pores and microcracks are very developed in tight sandstone structure, and there are many isolated pores. Compared with 1.5 μm scanning resolution, 0.62 μm scanning resolution presents a clearer pore network model, but due to the limited testing range at the nanoscale, the key structural information properties may be magnified.Critical microstructure information may be missed when the scanning resolution is greater than 2μm.Therefore, in the study of three-dimensional characteristics of pores and fractures in tight sandstone, high scanning accuracy should be selected and multi-region information acquisition should be carried out to effectively reveal the key microstructure features. This basic work provides a support for further effectively revealing the structural evolution information of tight rocks.

Anchored slide-resistant piles are one of the main supporting structures for landslides. To date, there is still a lack of systematic studies on the characteristics of the mechanics and deformation of anchored slide-resistant piles in weak-hard interbedded strata. This study taking weak-hard interbedded strata as the geological background, based on the self-developed flexible inclinometer and automatic loading system, the test system was constructed. Model tests of landslides reinforced by anchored slide-resistant piles were conducted, and the force and deformation characteristics of piles, anchor cables, and sliding mass were revealed in the process of increasing loading force. The influence of the layout of anchor cables on the force and deformation of the pile-anchor was analyzed. The influence mechanism of the stratum with weak-hard interbedded rock on the anchored slide-resistant piles was analyzed by numerical simulation. In addition, the theoretical analysis was carried out by taking the double-anchored pile as an example. The results show that: ① in the landslide-pile-anchor system, the deep displacement of the pile and sliding mass decreases with increasing pile depth, the growth rate of the rear is greater than that of the middle in the sliding mass, and the growth rate of the sliding mass is greater than that of the pile. ② The thrust sharing ratio of the pile-anchor undergoes four stages, which is approximately 9∶1 when it becomes stable. Meanwhile, the bending moment of the pile is distributed in an "S" shape under the action of the anchor cable tension, and the positive and negative bending moments are asymmetrical. ③ The growth rate of the anchor cable tension increases with the increase in the anchoring angle, and the influence of different anchoring angles on the internal force of the pile is mainly reflected in the loaded section. ④ The multianchored pile structure can share more thrust than the single-anchored pile, and the maximal bending moment values of the double-anchored pile and triple-anchored pile are reduced by 22.41% and 40.55%, respectively. ⑤ Compared with the homogeneous stratum, the stress of the bedrock at the interface between a weak and hard rock in the weak-hard interbedded stratum changes abruptly, and the thickness ratios of the weak rock and whether the pile bottom is embedded in hard rock all affect the axial force of the anchor cable and the pile-rock interaction to varying degrees.Meanwhile, the theoretical value for the internal force of the double-anchored pile is closer to the test result. The study results of this paper can provide evidence for the optimal design of projects for landslides reinforced by anchored slide-resistant piles in weak-hard interbedded strata.

Hydrodynamic-driven bedding rock landslides are the focus of research in the field of landslide geological hazards due to their large number, frequent disasters, and excessive harm. However, the understanding of the initiation mechanism of landslides is still insufficient, and the accurate prediction of landslides still faces great challenges. Because of this, this paper takes moderate-dip angle bedding rock landslides with weak interlayers as the research object and conducts a series of landslide model tests under the action of hydrodynamics by constructing an ideal single-layer landslide physical model. On this basis, the macroscopic deformation evolution process of the landslide and the erosion degradation characteristics of the slide zone soil is analyzed in depth. The results show that the failure of bedding rock landslides is associated with the slip surface roughness and dip angle and can go through four stages: the initial deformation stage, uniform deformation stage, accelerated deformation stage, and failure stage.The seepage erosion in the sliding zone causes the loss of aggregates, which reduces the shear strength and causes the slope to slide. Simultaneously, the compression-shear action and the deformation of the overlying slope also adversely affect erosion strength.Based on the variation law of soil cohesion in the sliding zone with hydraulic gradient and erosion time, a seepage-driven evolution model of soil cohesion in the sliding zone is proposed, which can describe the degradation process of soil cohesion in the sliding zone well. The existence of sliding surface roughness not only significantly affects the deterioration law of the sliding zone, but also changes the failure modes of different regions of the sliding zone. By considering the influence of the roughness on the failure modes of different areas of the sliding zone, the multi-effect correlation analysis of dynamic water is carried out, and the mechanical model of the landslide is established, which realizes the effective evaluation of the dynamic stability of the landslide. The research achievements in this study can provide a theoretical reference for predicting and preventing actual hydrodynamic-driven bedding rock landslides.

As a discipline, the science of natural hazards and disaster risk aims to explain the spatial-temporal pattern, process and mechanism, emergency response and risk mitigation of natural hazards, which requires a multidisciplinary and interdisciplinary approach. With the support of Natural Science Finance of China (NSFC) and Chinese Academy of Sciences (CAS), in-depth research and systematic analysis on natural hazards and disaster risk were conducted. In this paper, the state of the art in research on natural hazards is summarized from seven aspects: formation process, mechanism and dynamic of natural hazards, disaster risk assessment, forecast, monitoring and early warning, disaster mitigation, emergency treatment and rescue, risk management and post-disaster reconstruction. The trends within the natural hazards and disaster risk as a discipline were identified, along with existing shortcomings and significant gaps that need to be addressed. This paper highlighted: 1) the scientific challenges including the frontier scientific issues and technological gaps on natural hazards and disaster risk discipline from 2025 to 2035 in China, and 2) the proposal to develop a systemic and holistic natural hazards and disaster risk discipline.

Abstract Backgrounds Pregnancy termination during the second trimester in patients with placenta previa and placenta accreta spectrum (PAS) is a complex and challenging clinical problem. Based on our literature review, there has been a relative increase in the number of such cases being treated by hysterotomy and/or local uterine lesion resection and repair. In the present study, a retrospective analysis was conducted to compare the clinical outcomes when different management strategies were used to terminate pregnancy in the patients with placenta previa and PAS. Methods A total of 51 patients who underwent pregnancy termination in the second trimester in Beijing Obstetrics and Gynecology Hospital between June 2013 and December 2018 were retrospectively analyzed in this study. All patients having previous caesarean delivery (CD) were diagnosed with placenta previa status and PAS. Results ① Among the 51 patients, 16 cases received mifepristone and misoprostol medical termination, 15 cases received mifepristone and Rivanol medical termination, but 1 of them was transferred to hysterotomy due to failed labor induction, another 20 cases were performed planned hysterotomy. There was no placenta percreta cases and uterine artery embolization (UAE) was all performed before surgery.② There were 31 cases who underwent medical termination and 30 cases were vaginal delivery. Dilation and evacuation (D&E) were used in 20 cases of medical abortion failure and in all 30 cases of difficult manual removal of placental tissue. ③ A statistically significant difference was found among the three different strategies in terms of gestational weeks, the type of placenta previa status, main operative success rate and β-HCG regression time (P

Rainstorm is one of the most important factors for inducing landslide, but researches on the response mechanism of landslide deformation under the action of torrential rain are still insufficient. In view of this situation, Baijiabao landslide in the Three Gorges Reservoir area is taken as an example, to analyze the deformation response characteristics under the circumstance of rainstorm on the basis of detailed monitoring data. A landslide mutual information method is used to reveal the influences of rainfall and reservoir water level variation on the deformation of Baijiabao landslide under rainstorm conditions. The deformation of Baijiabao landslide is mainly affected by the variation of reservoir water level, and the expansion of slope surface cracks is mainly triggered by rainfall. Rainstorm is the main cause of the accelerated deformation of landslide after rain and rapid expansion of slope surface cracks located in the boundaries. The research method in this paper can be extended to the analysis of the response characteristics of landslide under the combined action of other multi-conditions and provide some references for disaster prevention and mitigation of the reservoir landslides under the similar effect of rainstorm conditions.

The mechanical behavior of loess is highly predicated on variation in its moisture content. While the impacts of the water content on the shearing behavior and collapsibility of loess have been extensively studied, its effect on tensile characteristics has received relatively little attention. In this study, a series of tensile tests were conducted on remolded specimens of a clayey loess that were collected from Ili Valley in China. Two sets of loess specimens with varying water contents were prepared separately using wetting and drying methods. The influence of the water content on the tensile stress–strain response, failure mode and tensile strength was investigated by combining the tensile test results and particle image velocimetry (PIV) analysis. On this basis, a nuclear magnetic resonance (NMR) test and scanning electron microscopy (SEM) observations were implemented in order to assist with the interpretation of the underlying mechanism. The test results indicate that the tensile failure process and the variation of tensile strength with varying water contents differ for specimens that are prepared with wetting and drying methods; a finding which arises from the differences in the soil microstructure, clay–water interaction and the distribution of capillary and adsorbed water. This research has shown that the tensile strength of clayey loess is essentially dominated by the clay’s hydration/cementation and the development of capillary and adsorption suction as well as the microstructural evolution that occurs with the change in the water content. Based on the experimental observations, a conceptual model is proposed in order to interpret the effect of water content on loess’ tensile behavior.

Montmorillonite (MMT) is highly sensitive to environmental changes and therefore plays a key role in the structural evolution of rocks and soils and even damage and disasters. The effects of important environmental factors (the temperature and water content) on MMT structural properties require in-depth study. The structure and morphology of sodium montmorillonite (Na-MMT) and its thermal products (micro-nanoparticles) were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). A molecular dynamics (MD) simulation was performed to investigate how temperature (below the failure temperature of the Na-MMT crystal layer) affects the structural properties of hydrated MMT. (1) The laboratory results showed that increasing the temperature significantly affected water molecules, and the particle aggregates exhibited inhomogeneous thermal expansion. The interlayer structure collapsed at 500–700°C. (2) In the simulation, the pull-off force inhibited interactions among oxides, crystal layers on both sides of the sample, and the bonding structure of water molecules, thus exposing the stress on the bonding body for analysis. The MMT ultimate stresses in the X, Y, and Z directions all trended downward with increasing water content and temperature. (3) Environmentally induced damage was most likely to occur in the Z direction. Increasing the number of interlayer water molecules increased the layer spacing and considerably weakened van der Waals forces, such that the roles of the electrostatic force and the interlayer hydrogen bond network gradually became significant. The most significant impact of increasing the temperature was reflected in the hydrogen bonding network, resulting in the destruction of the interlayer water bridge, the gradual failure of the layered bonding structure, and the formation or development of cracks. This improved understanding of the structural properties of MMT aggregates under environmental change advances research on the evolutionary behaviour of nano-, micro-, and macrostructures of rocks and soils.

The shear constitutive model of the slip zone soil can be used to quantitatively describe the relationship between shear stress and shear displacement, which is of great significance for the analysis of deformation mechanism and stability evaluation of landslides. The conventional shear constitutive models were usually proposed based on statistical damage theory with the Weibull distribution function, which is widely used in the field of rock material. However, there are great differences in the structure and mechanical properties of soil and rock; therefore, the suitability of the damage distribution functions for the slip zone soil needs to be further investigated. In this study, eight distribution functions are introduced to describe the damage evolution process of the slip zone soil and applied to two groups of shear stress–shear displacement curves (named shear curves) with different softening characteristics, i.e., strong softening type and weak softening type. The results show that: (1) the applicability of the various damage distribution functions to the two softening types of shear curves is obviously different; (2) the commonly used Weibull distribution is only suitable for the weak softening shear curves; (3) the shear constitutive models based on Gamma, Exponential, and Logistic distributions are the best three models for the strong softening curve; the shear constitutive models based on Gamma, Weibull, and Exponential distributions are the best three models for the weak softening curve; (4) Gamma distribution function is the optimal model in both strong softening and weak softening types of shear curves, and the parameters of the function have clear physical meaning in the shear constitutive model. In general, the Gamma distribution function can more objectively reflect the whole shear damage evolution process of the slip zone soil than other distribution functions.

Natural hazards deserve the use of state-of-the-art tools and techniques to cope with them [...]

Landslide displacement monitoring plays a fundamental role in the study of landslide evolution mechanisms, forecasting, risk assessment, prevention, and control. To fill the deficiencies of traditional instrumentation for measuring landslide displacement distributed along lateral direction, a landslide displacement measurement method based on deformation-coupled pipeline trajectory measurement is proposed, and a pipeline trajectory inertial measurement instrument is developed. The developed instrument, primarily comprised of a single shaft gyro, two axis accelerometers, and an external roller encoder, is designed as an axial half strapdown-radial half platform structure combined with a mechanical gravity platform. This structure avoids the singularity of pitch angle and roll angle and can expediently calculate a pipeline trajectory with an Eulerian transformation when obtaining several basic physical variables, e.g., the axial linear velocity, pitch angle, roll angle, and azimuth angle. Additionally, the pipeline trajectory, measured at different times, possesses the ability to reflect the displacement evolution feature of landslides. The results of prototype simulation tests imply a single measurement accuracy of a 12 cm/100 m span and a singly periodic multiple (more than five times) measurement accuracy of a 3 cm/100 m span, which meets medium-precision displacement measurement requirements for a landslide. Additionally, the finished instrument has been successfully applied to the deformation monitoring of the Majiagou I# landslide, which further verifies its feasibility and offers a reference for similar landslides.

To estimate the association between uterine fibroids and adverse obstetric outcomes.This was a retrospective cross-sectional study of 112,403 deliveries from 14 provinces and 39 different hospitals in 2011 in mainland China. We compared pregnancy outcomes in women with and without uterine fibroids who underwent detailed second trimester obstetric ultrasonography during 18 to 22 weeks. Obstetric outcomes include cesarean delivery, breech presentation, preterm delivery, placenta previa, placental abruption, premature rupture of membranes and neonatal birthweight. Univariate analyses and multivariate logistic regression analyses were performed.Of 112,403 women who underwent routine obstetric survey, 3,012 (2.68%) women were identified with at least 1 fibroid. By univariate and multivariate analyses, the presence of uterine fibroids was significantly associated with cesarean delivery (Adjusted odds radio [AOR] 1.8, 95% confidence interval [CI] 1.7-2.0), breech presentation (AOR 1.3, 95% CI 1.2-1.5) and postpartum hemorrhage (AOR 1.2, 95% CI 1.1-1.4). The size of uterine fibroids and location in uterus had important effect on the mode of delivery. The rates of PPH were significantly higher with increasing size of the uterine fibroid (P

This paper develops a new method to directly determine the composite elastic modulus of the reinforced con­crete cantilever pile rather than adopt theoretical or empirical approaches. On the basis of the theory of material mecha­nism, the load-deflection equation was deduced to create the relationship between the elastic modulus and the ratio of load-deflection. The numerical modelling tests based on ANSYS separation modelling technology were carried out to determine the composite elastic modulus under different reinforcement ratio, concrete strength grade and distribution pat­tern of driving force. The results can be used to create the quantitative relationship between the composite elastic modulus and reinforcement ratio as well as concrete strength grade. Comparison amongst various lateral load pattern were made to show that the deflection of pile head is obviously affected by the lateral load pattern, and the corresponding equations of the deflection of the pile head under different lateral load pattern were proposed, which can reflect the ranking of the great influence on the deflection of the pile head, rectangular, trapezoidal and triangular lateral load pattern in order. First published online: 24 Aug 2015

The physical model test of landslides is important for studying landslide structural damage, and parameter measurement is key in this process. To meet the measurement requirements for deep displacement in landslide physical models, an automatic flexible inclinometer probe with good coupling and large deformation capacity was designed. The flexible inclinometer probe consists of several gravity acceleration sensing units that are protected and positioned by silicon encapsulation, all the units are connected to a 485-comunication bus. By sensing the two-axis tilt angle, the direction and magnitude of the displacement for a measurement unit can be calculated, then the overall displacement is accumulated according to all units, integrated from bottom to top in turn. In the conversion from angle to displacement, two spline interpolation methods are introduced to correct and resample the data; one is to interpolate the displacement after conversion, and the other is to interpolate the angle before conversion; compared with the result read from checkered paper, the latter is proved to have a better effect, with an additional condition that the displacement curve move up half the length of the unit. The flexible inclinometer is verified with respect to its principle and arrangement by a laboratory physical model test, and the test results are highly consistent with the actual deformation of the landslide model.

Hypertensive disorders of pregnancy (HDP) are a group of medical complications in pregnancy and also a risk factor for severe pregnancy outcomes, but it lacks a large-scale epidemiological investigation in recent years. This survey represents a multicenter cross-sectional retrospective study to estimate the prevalence and analyze the risk factors for HDP among the pregnant women who had referred for delivery between January 1st 2011 and December 31st 2011 in China Mainland. A total of 112,386 pregnant women were investigated from 38 secondary and tertiary specialized or general hospitals randomly selected across the country, of which 5,869 had HDP, accounting for 5.22% of all pregnancies. There were significant differences in the prevalence of HDP between geographical regions, in which the North China showed the highest (7.44%) and Central China showed the lowest (1.23%). Of six subtypes of HDP, severe preeclampsia accounted for 39.96%, gestational hypertension for 31.40%, mild preeclampsia for 15.13%, chronic hypertension in pregnancy for 6.00%, preeclampsia superimposed on chronic hypertension for 3.68% and eclampsia for 0.89%. A number of risk factors for HDP were identified, including twin pregnancy, age of >35 years, overweight and obesity, primipara, history of hypertension as well as family history of hypertension and diabetes. The prevalence of pre-term birth, placental abruption and postpartum hemorrhage were significantly higher in women with HDP than those without HDP. The possible risk factors confirmed in this study may be useful for the development of early diagnosis and appropriate treatment of HDP.

Abstract One question in lymphocyte homing is how integrins are rapidly activated to enable immediate arrest of fast rolling lymphocytes upon encountering chemokines at target vascular beds given the slow chemokine-induced integrin inside-out activation. Herein we demonstrate that chemokine CCL25-triggered Ca2+ influx induces T cell membrane-proximal external Ca2+ concentration ([Ca2+]ex) drop in 6 s from physiological concentration 1.2 mM to 0.3 mM, a critical extracellular Ca2+ threshold for inducing αLβ2 activation, triggering rapid αLβ2 activation and T cell arrest before occurrence of αLβ2 inside-out activation. Talin knockdown inhibits the slow inside-out activation of αLβ2 but not [Ca2+]ex drop-triggered αLβ2 quick activation. Blocking Ca2+ influx significantly suppresses T cell rolling-to-arrest transition and homing to skin lesions in a mouse psoriasis model, thus alleviating skin inflammation. [Ca2+]ex decrease-triggered rapid integrin activation bridges the gap between initial chemokine stimulation and slow integrin inside-out activation, ensuring immediate lymphocyte arrest and subsequent diapedesis on the right location.

The Northwest Pacific Ocean is the most productive fishing ground in the Pacific Ocean, with a continuous rise in water temperature since 1990. We developed stacked species distribution models (SSDMs) to estimate the impacts of climate change on the distribution dynamics of economically significant species under three climate change scenarios for the periods 2040-2060 and 2080-2100. Overall, water temperature is the most important factor in shaping the distribution patterns of species, followed by water depth. The predictive results indicate that all the species show a northward migration in the future, and the migration distance varies greatly among species. Most pelagic species will expand their habitats under climate change, implying their stronger adaptability than benthic species. Tropical fishes are more adaptable to climate change than species in other climate zones. Though limitations existed, our study provided baseline information for designing a climate-adaptive, dynamic fishery management strategy for maintaining sustainable fisheries.