Ginger oil-loaded transdermal adhesive patch treats post-traumatic stress disorder

Objective:To find a viable alternative to reduce the number of doses required for the patients with post-traumatic stress disorder(PTSD),and to improve efficacy and patient compliance.Methods: In this study,we used ginger oil,a phytochemical with potential therapeutic properties,to prepare ginger oil patches.High-performance liquid chromatography(HPLC)was used to quantify the main active component of ginger oil,6-gingerol.Transdermal absorption experiments were conducted to optimize the various pressure-sensitive adhesives and permeation enhancers,including their type and concentration.Subsequently,the ginger oil patches were optimized and subjected to content determination and property evaluations.A PTSD mouse model was established using the foot-shock method.The therapeutic effect of ginger oil patches on PTSD was assessed through pathological sections,behavioral tests,and the evaluation of biomarkers such as tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),brain-derived neurotrophic factor(BDNF),and melatonin(MT).Results: The results demonstrated that ginger oil patches exerted therapeutic effects against PTSD by inhibiting inflammatory responses and modulating MT and BDNF levels.Pharmacokinetic experiments revealed that ginger oil patches maintained a stable blood drug concentration for at least one day,addressing the rapid metabolism drawback of 6-gingerol and enhancing its therapeutic efficacy.Conclusions: Ginger oil can be prepared as a transdermal drug patch that meets these requirements,and the bioavailability of the prepared patch is better than that of oral administration.It can improve PTSD with good patient compliance and ease of administration.Therefore,it is a promising therapeutic formulation for the treatment of PTSD.

Application of multi-algorithm ensemble methods in high-dimensional and small-sample data of geotechnical engineering:A case study of swelling pressure of expansive soils

Geotechnical engineering data are usually small-sample and high-dimensional,which brings a lot of challenges in predictive modeling.This paper uses a typical high-dimensional and small-sample swell pressure(P_(s))dataset to explore the possibility of using multi-algorithm hybrid ensemble and dimensionality reduction methods to mitigate the uncertainty of soil parameter prediction.Based on six machine learning(ML)algorithms,the base learner pool is constructed,and four ensemble methods,Stacking(SG),Blending(BG),Voting regression(VR),and Feature weight linear stacking(FWL),are used for the multi-algorithm ensemble.Furthermore,the importance of permutation is used for feature dimensionality reduction to mitigate the impact of weakly correlated variables on predictive modeling.The results show that the proposed methods are superior to traditional prediction models and base ML models,where FWL is more suitable for modeling with small-sample datasets,and dimensionality reduction can simplify the data structure and reduce the adverse impact of the small-sample effect,which points the way to feature selection for predictive modeling.Based on the ensemble methods,the feature importance of the five primary factors affecting P_(s) is the maximum dry density(31.145%),clay fraction(15.876%),swell percent(15.289%),plasticity index(14%),and optimum moisture content(13.69%),the influence of input parameters on P_(s) is also investigated,in line with the findings of the existing literature.

Negative pressure device-assisted autologous fat grafting: A case report

This report describes a novel technique for improving depressed scars using negative pressure suction-assisted autologous fat grafting.A 35-year-old woman presented with a 20-year history of bilateral central buttock con-cavities,causing aesthetic concerns.To maximize fat graft survival and enhance tissue volume,we implemented intermittent negative pressure suction on the recipient area for one month preoperatively.The patient expressed satisfaction with the cosmetic outcome,and a three-month follow-up confirmed a significantly improved fat graft survival rate.This minimally invasive,cost-effective,and easily reproducible technique offers a promising clinical strategy for treating depressed scars.

Pore-scale study of the pressure-sensitive effect of sandstone and its influence on multiphase flows

The pressure-sensitive effect on the pore structure of sandstone was investigated using X-ray computed micro-tomography and QEMSCAN quantitative mineral analysis. In a physical simulation study, we extracted the pore network model from digital cores at different confining pressures and evaluated the effect of pressure sensitivity on the multiphase displacement process. In both the pore network model and QEMSCAN scanning, the pore structure was observed to be damaged under a high confining pressure. Due to their different scales, the pores and throats exhibited inhomogeneous changes; further, the throats exhibited a significant variation compared to that exhibited by the pores. Meanwhile, the heterogeneity of the pore structure under the two aforementioned activities was aggravated by the elastic-plastic deformation of the pore structure.The pressure-sensitive effect increased the proportion of mineral particles, such as quartz(the main component of the core skeleton), and reduced the proportion of clay minerals. The clay minerals were originally attached to the pore walls or interspersed in the pores; however, as the pressure increased, the clay minerals accumulated in the pores resulting in blockage of the pores. While simulating the multiphase displacement process, increasing the confining pressure was observed to severely restrict the flowability of oil and water. This study promises to improve the efficiency of reservoir development in terms of oil and gas exploitation.

Simulation of the Pressure-Sensitive Seepage Fracture Network in Oil Reservoirs with Multi-Group Fractures

Stress sensitivity is a very important index to understand the seepage characteristics of a reservoir.In this study,dedicated experiments and theoretical arguments based on the visualization of porous media are used to assess the effects of the fracture angle,spacing,and relevant elastic parameters on the principal value of the permeability tensor.The fracture apertures at different angles show different change rates,which influence the relative permeability for different sets of fractures.Furthermore,under the same pressure condition,the fractures with different angles show different degrees of deformation so that the principal value direction of permeability rotates.This phenomenon leads to a variation in the water seepage direction in typical water-injection applications,thereby hindering the expected exploitation effect of the original well network.Overall,the research findings in this paper can be used as guidance to improve the effectiveness of water injection exploitation in the oil field industry.

Numerical investigation of a coupled moving boundary model of radial flow in low-permeable stress-sensitive reservoir with threshold pressure gradient

The threshold pressure gradient and formation stress-sensitive effect as the two prominent physical phenomena in the development of a low-permeable reservoir are both considered here for building a new coupled moving boundary model of radial flow in porous medium. Moreover, the wellbore storage and skin effect are both incorporated into the inner boundary conditions in the model. It is known that the new coupled moving boundary model has strong nonlinearity. A coordinate transformation based fully implicit finite difference method is adopted to obtain its numerical solutions. The involved coordinate transformation can equivalently transform the dynamic flow region for the moving boundary model into a fixed region as a unit circle, which is very convenient for the model computation by the finite difference method on fixed spatial grids. By comparing the numerical solution obtained from other different numerical method in the existing literature, its validity can be verified. Eventually, the effects of permeability modulus, threshold pressure gradient, wellbore storage coefficient, and skin factor on the transient wellbore pressure, the derivative, and the formation pressure distribution are analyzed respectively.

BLOOD PRESSURE CHANGE WITH AGE IN SALT-SENSITIVE TEENAGERS

Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing. Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years. Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teena-gers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8 ±5.2 mmHg, P< 0.01; 12.2% ±12.0% vs. 2.5% ±4.4%, P< 0.001, respectively). There was a similar trend for diastolic blood pressure (8.4 ±6.4 mmHg vs. 3.7 ±6.4 mmHg, P= 0.052; 13.2% ±10.6 % vs. 6.8% ±10.1%, P= 0.053, respectively). Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.

Numerical simulation of influence of viscous adhesive stress on viscous pressure bulging process of hemispherical sphere

The mechanical model of viscous pressure bulging process is presented. The viscous pressure bulging process of hemispherical sphere is analyzed by the numerical simulation and experiments. The research results show that the viscosity of viscous medium significantly affected the thickness distribution, strain distribution and shape of hemispherical sphere, which provides analytic basis for selecting reasonably viscous medium and designing process of viscous pressure forming.

Pressure-sensitive plasticity of lithiated silicon in Li-ion batteries

Lithiation-induced plasticity is a key factor that enables Si electrodes to maintain long cycle life in Li-ion batteries. We study the plasticity of various lithiated sili-con phases based on first-principles calculations and iden-tify the linear dependence of the equivalent yield stress on the hydrostatic pressure. Such dependence may cause the compression-tension asymmetry in an amorphous Si thin film electrode from a lithiation to delithiation cycle, and leads to subsequent ratcheting of the electrode after cyclic lithiation. We propose a yield criterion of amorphous lithi-ated silicon that includes the effects of the hydrostatic stress and the lithiation reaction. We further examine the micro-scopic mechanism of deformation in lithiated silicon under mechanical load, which is attributed to the flow-defects mediated local bond switching and cavitation. Hydrostatic compression confines the flow defects thus effectively strength-ens the amorphous structure, and vice versa.

Influence of Working Pressure on Ion Sensitive Probe Measurement in Microwave ECR Plasmas

In order to precisely measure the ion parameters in a microwave electron cyclotron resonance plasma using an ion sensitive probe,the dependences of the current-voltage（I-V）characteristics on the shielding height（h）and the potential difference between inner and outer electrodes（V_B）have been investigated at different working pressures of 0.03 Pa and 0.8 Pa.Results show that the I-V curves at higher pressure are more sensitive to the variation of h than those at lower pressure.The influence of V_B on ion temperature（T_i）measurement becomes more prominent when the pressure is increased from 0.03 Pa to 0.8 Pa.Under both pressures,the optimized h is obtained at the condition where the current reaches zero in the positive voltage region with a suitable V_B of-1.5 V because of effective shielding of the electron E×B drift.

Pre-placement of adhesive tape around wound sites can prevent air leakage in negative pressure wound therapy procedures

The introduction of negative pressure wound therapy has revolutionized the management of complicated wounds.However,the maintenance of an effective negative pressure environment is difficult in some instances,such as wounds in close proximity to an intestinal stoma or wounds surrounded by external fixations.We found that adhesive tape adheres more easily to itself than to wet skin or uneven surfaces.Therefore,we placed adhesive tape around surgical wounds prior to covering them with foam and sealing them with more tape.As a result of the strong adhesive force between pieces of tape,this method could provide a better environmental seal,even in situations where space is limited.Pre-placed adhesive tape around the wound site prior to foam placement could provide sufficient adhesion to maintain a continuous negative pressure environment during treatment.

Element Analysis of Instrumented Sharp Indentations into Pressure-sensitive Materials

Finite element analysis was carried out to investigate the conical indentation response of elastic-plastic solids within the framework of the hydrostatic pressure dependence and the power law strain hardening. A large number of 40 difierent combinations of elasto-plastic properties with n ranging from 0 to 0.5 and σy/E ranging from 0.0014 to 0.03 were used in the computations. The loading curvature C and the average contact pressure Pave were considered within the concept of representative strains and the dimensional analysis.Dimensionless functions associated with these two parameters were formulated for each studied value of the pressure sensitivity. The results for pressure sensitive materials lie between those for Von Mises materials and the elastic model.

Test and Study of the Rock Pressure Sensitivity for KeLa-2 Gas Reservoir in the Tarim Basin

KeLa-2 gas reservoir is the largest uncompartimentalized gas field so far discovered in China, with a reserve of hundreds of billions of cubic meters of dry gas. It has such features as extremely long interval (550m), high pressure (74.5MPa) and pressure coefficient (2.022). Gas reservoirs with a pressure coefficient of over 2.0 are not commonly found. The abnormal high-pressure reservoirs are quite different in characteristic and performance during the process of depletion exploitation. Therefore, it is necessary to know the property of pressure sensitivity for this abnormal high-pressure reservoir. The aim of this paper is to test the reservoir pressure sensitivity and to analyze its effect on the deliverability of gas. Through some experiments, the permeability change with the confining pressure of rock samples from KeLa-2 abnormal high-pressure gas reservoir is measured. A power function is used to match the measured data, and to derive an empirical equation to describe the change of permeability through the change of the reservoir pressure or effective overburden pressure. Considering the permeability change during the development of reservoirs, a conventional deliverability equation is modified, and the deliverability curve for KeLa-2 gas reservoir is predicted. The research indicates that the extent of the pressure sensitivity of rock samples from KeLa-2 is higher than that from the Daqing oilfield. KeLa-2 reservoir rock has the feature of an undercompaction state. The pressure sensitivity of a reservoir may decrease the well deliverability. It is concluded that for KeLa-2 reservoir the predicted absolute open flow (AOF), when the pressure sensitivity is taken into account, is approximately 70% of the AOF when permeability is constant and does not change with pressure.

Static solution on four-region spherial cavity expansion model in a pressure sensitive medium

Spherical cavity expansion model is often used to study the mechanic characteristics of pressure sensitive mediums. The most important one we do in the paper is that we construct a four-region model with σθ≠0 in damage region,which is different from what Satapathy did before and is more reasonable. By adopting this model,different constitutive equations were constructed by different method-elastic mechanics in elastic region,damage mechanics and fracture mechanics in damage region,and macro-micro mechanics theory in plastic region. Then using Durban's self-similarity assumption,the control differential equations with boundary conditions were established,and the static numerical solution of stress field and displacement field in the three different regions of elastic,damage and plastic area were discussed respectively. Results showed that this four-region model can describe precisely the mechanic characteristics of pressure sensitive mediums under initial pressure.

Field-assisted tunneling enabled pressure-sensitive composites/sensors for smart concrete structures

Spiky spherical nickel powder with sharp nano-tips on its surface is a kind of excellent fillers for developing pressure-sensitive cement-based composites/sensors for traffic detection,structural health monitoring,and border and military security.The sharp nano-tips on the surface of spiky spherical nickel particles can induce field emission and tunneling effects,which leads to the ultrahigh pressure-sensitive responses of the cement-based composites.In this paper,we systematically introduce research on nanotip-induced ultrahigh pressure-sensitive cement-based composites/sensors,with attentions to their pressure-sensitive property and sensing mechanism,pressure-sensitive characteristic model,and smart structure system for traffic detection.

Pressure-induced strongadhesion between chitosan nanofilms

The surface and adhesion forces between chitosan- coated mica surfaces in an acetic acid buffer solution were measured using a surface force apparatus （SFA）. The force- distance profiles were obtained under different pressure conditions. It was found that the chitosan was adsorbed on the mica surface and formed a stable nanofilm under acid conditions. The adsorbed chitosan nanofilms induced a short- range monotonically steric force when two such surfaces came close in the acid buffer. The adhesion forces between the two chitosan-coated mica surfaces varied with the loads. Strong adhesion between the two chitosan-coated mica surfaces was observed at high pressure. Such pressure-dependent adhesion properties are most likely related to the molecular configurations and hydrogen bonds reordering under high confinement.

High-Porosity Foam-Based Iontronic Pressure Sensor with Superhigh Sensitivity of 9280 kPa^(-1)

Flexible pressure sensors with high sensitivity are desired in the fields of electronic skins,human-machine interfaces,and health monitoring.Employing ionic soft materials with microstructured architectures in the functional layer is an effective way that can enhance the amplitude of capacitance signal due to generated electron double layer and thus improve the sensitivity of capacitive-type pressure sensors.However,the requirement of specific apparatus and the complex fabrication process to build such microstructures lead to high cost and low productivity.Here,we report a simple strategy that uses open-cell polyurethane foams with high porosity as a continuous three-dimensional network skeleton to load with ionic liquid in a one-step soak process,serving as the ionic layer in iontronic pressure sensors.The high porosity(95.4%) of PU-IL composite foam shows a pretty low Young's modulus of 3.4 kPa and good compressibility.A superhigh maximum sensitivity of 9,280 kPa^(-1) in the pressure regime and a high pressure resolution of 0.125% are observed in this foam-based pressure sensor.The device also exhibits remarkable mechanical stability over 5,000 compression-release or bending-release cycles.Such high porosity of composite structure provides a simple,cost-effective and scalable way to fabricate super sensitive pressure sensor,which has prominent capability in applications of water wave detection,underwater vibration sensing,and mechanical fault monitoring.

Accumulation and exploration enlightenment of shallow normal-pressure shale gas in southeastern Sichuan Basin, SW China

Based on the drilling, logging, experimental and testing data of Well PD1, a shallow normal-pressure shale gas well in the Laochangping anticline in southeastern Sichuan Basin, the shallow shale gas reservoirs of the Ordovician Wufeng Formation to Silurian Longmaxi Formation (Wufeng-Longmaxi) were investigated in terms of geological characteristics, occurrence mechanism, and adsorption-desorption characteristics, to reveal the enrichment laws and high-yield mechanism of shallow normal-pressure shale gas in complex structure areas. First, the shallow shale gas reservoirs are similar to the medium-deep shale gas reservoirs in static indicators such as high-quality shale thickness, geochemistry, physical properties and mineral composition, but the former is geologically characterized by low formation pressure coefficient, low gas content, high proportion of adsorbed gas, low in-situ stress, and big difference between principal stresses. Second, shallow shales in the complex structure areas have the gas occurrence characteristics including low total gas content (1.1-4.8 m3/t), high adsorbed gas content (2.5-2.8 m3/t), low sensitive desorption pressure (1.7-2.5 MPa), and good self-sealing. Third, the adsorbed gas enrichment of shales is mainly controlled by organic matter abundance, formation temperature and formation pressure: the higher the organic matter abundance and formation pressure, the lower the formation temperature and the higher the adsorption capacity, which is more beneficial for the adsorbed gas occurrence. Fourth, the shallow normal-pressure shale gas corresponds to low sensitive desorption pressure. The adsorbed gas can be rapidly desorbed and recovered when the flowing pressure is reduced below the sensitive desorption pressure. Fifth, the exploration breakthrough of Well PD1 demonstrates that the shallow complex structure areas with adsorbed gas in dominance can form large-scale shale reservoirs, and confirms the good exploration potential of shallow normal-pressure shale gas in the margin of the Sichuan Basin.

Temperature dependence of pressure sensitive flow in bulk metallic glass composites

The constraint factor,C,defined as hardness,H,to the yield strength,σ_(y),ratio,is an indirect measure of the pressure sensitivity in materials.Previous investigations determined that while C is less than 3 for crystalline materials,and remains invariant with change in temperature,it is greater than 3 for bulk metallic glasses(BMGs)and increases with increasing temperature,below their glass transition temper-ature,T_(g).In this study,the variations in C for two BMG composites(BMGCs),which have an amorphous matrix and in situ precipitated crystallineβ-Ti dendrites,which in one case transforms under stress toα”-Ti and deforms by slip in the other,as a function of temperature are examined and compared with that of a BMG.For this purpose,instrumented indentation tests,with a Berkovich tip,and uniaxial com-pression tests were performed to measure the H andσ_(y),respectively,on all alloys and their constituents at temperatures in the range of 0.48 T_(g)and 0.75 T_(g).σ_(y)and H of the BMGC with transforming dendrites(BMGC-T)increase and remain invariant with increasing temperature,respectively.Alternately,in BMG and the BMGC with non-transforming dendrites(BMGC–NT),the same properties decrease with increas-ing temperature.BMGC-T has the highest C of∼4.93 whereas that of BMGC–NT and BMG are∼3.72 and∼3.28,respectively,at 0.48 T_(g).With increasing temperature,C of the BMG and BMGC–NT increases with temperature,but that of the BMGC-T decreases.The values of C and their variations as a function of temperature were explained by studying the variation of pressure sensitivity of the amorphous phase and concluding that the plastic flow in BMGCs under constrained conditions,such as indentation,is con-trolled by the flow resistance of the amorphous matrix whereas that in uniaxial compression,which is only partially constrained,is controlled by plasticity in both the dendrites and matrix.

Soil Pressure Mini-sensor Made of Monocrystalline Silicon and the Measurement of Its Sensitivity Coefficient

A calibration test was done in order to measure its sensitivity coefficient by an improved soil test device.The experimental result shows that the soil pressure min-sensor made of the monocrystalline silicon（SPMMS）is proved to be good linear,high precision and less that can fetch precise data in low pressure range even near by O point,which guarantees the reliability of the soil pressure test in geotechnical engineering.