This paper is a statistical survey of Southern Hemisphere cold and hot polar cap patches,in relation to the interplanetary magnetic field(IMF)and ionospheric convection geometry.A total of 11,946 patch events were ide...This paper is a statistical survey of Southern Hemisphere cold and hot polar cap patches,in relation to the interplanetary magnetic field(IMF)and ionospheric convection geometry.A total of 11,946 patch events were identified by Defense Meteorological Satellite Program(DMSP)F16 during the years 2011 to 2022.A temperature ratio of ion/electron temperature(T_(i)/T_(e))<0.68 is recommended to define a hot patch in the Southern Hemisphere,otherwise it is defined as a cold patch.The cold and hot patches have different dependencies on IMF clock angle,while their dependencies on IMF cone angle are similar.Both cold and hot patches appear most often on the duskside,and the distribution of cold patches gradually decreases from the dayside to the nightside,while hot patches have a higher occurrence rate near 14 and 21 magnetic local time(MLT).Moreover,we compared the key plasma characteristics of polar cap cold and hot patches in the Southern and Northern Hemispheres.The intensity of the duskside upward field-aligned current of patches in the Southern Hemisphere(SH)is stronger than that in the Northern Hemisphere(SH),which may be due to the discrepancy in conductivities between the two hemispheres,caused by the tilted dipole.In both hemispheres,the downward soft-electron energy flux of the dawnside patches is significantly greater than that of the duskside patches.展开更多
Our work was to study the preparation,physicochemical characterization,and in vitro characteristic of Zingiber cassumunar blended patches.The Z.cassumunar blended patches incorporating Z.cassumunar Roxb.also known as ...Our work was to study the preparation,physicochemical characterization,and in vitro characteristic of Zingiber cassumunar blended patches.The Z.cassumunar blended patches incorporating Z.cassumunar Roxb.also known as Plai were prepared from chitosan and polyvinyl alcohol with glycerin as plasticizer.They were prepared by adding all ingredients in a beaker and homogeneously mixing them.Then,they were transferred into Petri-dish and dried in hot air oven.The hydrophilic nature of the Z.cassumunar blended patches was confirmed by the moisture uptake,swelling ratio,erosion,and porosity values.The FTIR,DSC,XRD,and SEM studies showed revealed blended patches with amorphous region that was homogeneously smooth and compact in both surface and cross section dimensions.They exhibited controlled the release behavior of(E)-4-(30,40-dimethoxyphenyl)but-3-en-lol(compound D)that is the main active compound in Z.cassumunar for anti-inflammation activity.However,in in vitro skin permeation study,the compound D was accumulated in newborn pig skin more than in the receptor medium.Thus,the blended patches showed the suitable entrapment and controlled release of compound D.Accordingly,we have demonstrated that such chitosan and polyvinyl alcohol formulated patches might be developed for medical use.展开更多
With the development of pharmaceutics and other disciplines theories and advanced technologies, the application of many new drug delivery systems has gradually increased in clinical veterinary. Among the many drug del...With the development of pharmaceutics and other disciplines theories and advanced technologies, the application of many new drug delivery systems has gradually increased in clinical veterinary. Among the many drug delivery systems, transdermal patch can maintain stable and effective plasma concentration and therapeutic effect in vivo for a long time after skin dressing delivery, which provides a safe and effective drug-delivery way for the therapy and prevention of some chronic diseases and partial analgesia in a simple and convenient way. Veterinary drug transdermal preparations have been developed both at home and abroad, and satisfactory results have been achieved in the experimental application. Based on the study of veterinary transdermal patches at home and abroad, this paper systematically describes the development and characteristics of transdermal patches, the factors affecting skin permeation and the evaluation this type of preparations in veterinary drugs.展开更多
For the truss structure composed of active-elements with piezoelectric patches affixed to its surface,taking the mechani-cal-electric coupling effect under the action of electric loads and mechanical loads into consid...For the truss structure composed of active-elements with piezoelectric patches affixed to its surface,taking the mechani-cal-electric coupling effect under the action of electric loads and mechanical loads into consideration,the finite element model for static force analysis is established by using the theory of mechanics. The failure mechanism of piezoelectric elements is discussed and the failure criteria of piezoelectric elements are proposed. The expression of safety margins for the element of piezoelec...展开更多
The objective of the present study is to examine cardiovascular protective action of a newly developed transdermal patch by incorporating bisoprolol and isosorbide dinitrate in spontaneously hypertensive rats. As the ...The objective of the present study is to examine cardiovascular protective action of a newly developed transdermal patch by incorporating bisoprolol and isosorbide dinitrate in spontaneously hypertensive rats. As the combination therapy with these two synergistic drugs at low doses through a suitable form of administration could provide optimal therapeutic benefit, we further evaluated the effects of a 42 d period of anti-hypertensive treatment in spontaneously hypertensive rats. Rats were divided into the following five groups: control (blank patch), bisoprolol fumarate tablets (BP-FT, 20.0 mg/kg, i.g.), bisoprolol transdermal patch (BP-TP, 20.0 mg/kg), isosorbide dinitrate transdermal patch (ISDN-TP, 20.0 mg/kg), and the combination of BP and ISDN in a transdermal patch at low doses (8 and 12 mg/kg, respectively). The effects of treatment were evaluated via biochemical indicators related to cardiovascular protection, structure and function. The combination therapy had synergistic anti-hypertensive effects and significantly reduced blood pressure with the benefit of controlling blood pressure variability compared to BP-FT and BP-TP. The combined treatment also reduced heart rate as well as BP-FT and BP-TP, while ISDN-TP had no evident effects on blood pressure, heart rate, and cardiovascular protection. Combination therapy was superior to BP-TP and BP-FT at increasing blood atrial natriuretic peptide and nitric oxide, while also reducing cardiac hydroxyproline and endothelin-1 with no difference in blood endothelin-1 and cardiac malondialdehyde levels. Cardiovascular remodeling differed among the groups, with the combination therapy reducing cardiac hypertrophy and the aortic media/lumen ratio. The consequential improvements in relaxation in response to cumulative concentrations of acetylcholine may explain the associated improvement in endothelial function. Combi- nation treatment with a transdermal patch exhibited a synergistic therapeutic effect. Such favorable cardiovascular effects with nitric oxide donors and β-blockade combination through a transdermal patch may provide long-term cardiovascular protection during anti-hypertensive treatment.展开更多
The dynamics of soil seed banks and seed movement was investigated in three bare alkali-saline patches in Songnen grassland, Northeast China, for exploring their potential role in the vegetation restoration of bare al...The dynamics of soil seed banks and seed movement was investigated in three bare alkali-saline patches in Songnen grassland, Northeast China, for exploring their potential role in the vegetation restoration of bare alkali-saline patches. The results showed that the seed banks and the seed movement in these patches were very similar to each other, and to some extent the seed movement was related to patch-side vegetation there. Seed movement across the soil surface of these bare alkali-saline patches was abundant and dominated by the seeds of pioneer species, such as Chloris virgata and Suaeda corniculata, which accounted for over 96% of these trapped seeds. In the contrast, soil seed banks of bare patches were extremely small, in different seasons, especially in May and June, even no any seed have been found, mainly due to lowest retaining capacity of surface soil to those abundant seed movement. Both soil seed banks and seed movement showed seasonal variation, and usually reached the maximum in October. Soil seed banks of bare alkali-saline patches, which were extremely small and difficult to recruit naturally, may inhibit speed of vegetation restoration. It is suggested that seed movement would be the potential seed source and play a potentially important role in the process of vegetation restoration of bare alkali-saline patches by enhancing the soft retaining capacity to seed movement.展开更多
Myocardial infarction(MI)is one of the common cardiovascular diseases that occurs with a blockage in one or more of the coronary arteries to lead to the damage of the myocardium,resulting in a lifethreatening conditio...Myocardial infarction(MI)is one of the common cardiovascular diseases that occurs with a blockage in one or more of the coronary arteries to lead to the damage of the myocardium,resulting in a lifethreatening condition.To repair the damaged myocardium in MI,researchers are looking forwards to new ways to postpone the progression of myocardial injury.Cardiac patches,the scaffolds layered on the heart surface,can provide mechanical support for the infarction site and improve cardiac function by delivering various bioactive factors or cells,showing considerable curative effect in the treatment of MI.Biomaterials with certain biocompatibility and mechanical properties have received widespread attention for the application in cardiac patches.In this review,we focus on the recent progress on these biomaterialsbased cardiac patches,which could be categorized into two types according to the sources of materials including(ⅰ)natural materials and(ⅱ)synthetic materials.The major advantages and current challenges of each type are discussed and a brief perspective on the future research directions is presented.展开更多
Objective:To achieve transbuccal release of carbamazepine by loading in unidirectional release mucoadhesive buccal patches.Methods:Buccal patches of carbamazepine with unidirectional drug release were prepared using h...Objective:To achieve transbuccal release of carbamazepine by loading in unidirectional release mucoadhesive buccal patches.Methods:Buccal patches of carbamazepine with unidirectional drug release were prepared using hydroxypropyl methyl cellulose,polyvinyl alcohol,polyvinyl pyrrolidone and ethyl cellulose by solvent casting method.Water impermeable backing layer(Pidilite?Biaxially-oriented polypropylene film)of patches provided unidirectional drug release.They were evaluated for thickness,mass uniformity,surface pH and folding endurance.Six formulations FA2,FA8,FA10,FBI,FB14 and FB16(folding endurance above 250)were evaluated further for swelling studies,ex vivo mucoadhesive strength,ex vivo mucoadhesion time,in vitro drug release,ex vivo permeation,accelerated stability studies and FTIR and XRD spectral studies.Results:The ex vivo mucoadhesion time of patches ranged between 109 min(FA10)to 126 min(FB14).The ex vivo mucoadhesive force was in the range of 0.278 lo 0.479 kg/m/s.The in vitro drug release studies revealed that formulation FA8 released 84%and FB16 released 99.01%of drug in140 min.Conclusions:The prepared unidirectional buccal patches of carbamazepine provided a maximum drug release within specified mucoadhesion period and it indicates a potential alternative drug delivery system for systemic denvery of carbamazepine.展开更多
We presented a 20-year-old patient with Crohn's disease (CD).Colonoscopy revealed longitudinal ulceration in the terminal ileum and rectal aphtoid ulcers.After treatment with mesalamine and total parenteral nutrit...We presented a 20-year-old patient with Crohn's disease (CD).Colonoscopy revealed longitudinal ulceration in the terminal ileum and rectal aphtoid ulcers.After treatment with mesalamine and total parenteral nutrition,repeat colonoscopy revealed a granular elevated area in the terminal ileum,which appeared as an irregular dome-like elevation with irregularly arranged villi on magnifying endoscopy.Biopsy specimens taken from the region showed microgranulomas and lymphoid hyperplasia,Scanning electron microscopy revealed the presence of M cells,confirming that the area corresponded to Peyer's patches.Peyer's patches by magnifying endoscopy and electron microscopy may provide insights into the pathogenesis of CD.展开更多
Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patch...Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems.The dye coverage,uniform infiltration depth,maximum infiltration depth,total stained area and heterogeneous infiltration stained area were measured by two indices,the maximum infiltration depth index(MIDI)and heterogeneous infiltration index(HII),which were calculated by processing dye-stained photos.The MIDI and HII of soil under shrubs were 1.41±0.14 and 0.29±0.068,respectively,and larger than those of grass soil,1.26±0.14 and0.20±0.076.Using the MIDI,HII,field soil moisture and rainfall data,the infiltration depth and heterogeneous infiltration amount for 26 nature rainfall events were calculated.The results imply that water can infiltrate to a deeper layer beneath shrub canopy than beneath grass patches and that more water infiltration occurs beneath shrub canopy than beneath grass patches.These results are of prime importance for arid and semiarid ecosystems with a limited water supply due to high evaporation and low precipitation.展开更多
A new dual-polarized staggered and stacked patches antenna with wide impedance band-width and high isolation is proposed.The antenna consists of two groups of radiation patches,in 7 layers,and uses the orthogonal adja...A new dual-polarized staggered and stacked patches antenna with wide impedance band-width and high isolation is proposed.The antenna consists of two groups of radiation patches,in 7 layers,and uses the orthogonal adjacent coupling structure on staggered layer to excite a pair of linear polarization modes.Thanks to the staggered feeder mode,it has increased the isolation performance be-tween ports and compressed the transverse size of the antenna.As a result of the combination of staggered stack-up between the patches and the stepped gradient shape of the main radiating patches,it has effectively expanded the impedance bandwidth of the antenna.The proposed antenna is simulated,fabricated and measured.The staggered feeding structure effectively reduces the cross-sectional area of the antenna,and greatly improves the isolation between feeding ports.The measurement results show that the impedance bandwidths for vertical and horizontal polarization modes are 40.2%(638-960 MHz)and 40.0%(645-968 MHz)respectively when the return loss is lower than-10 dB,and the isolation between feeding ports is better than-30 dB.Meanwhile,the antenna has a stable and symmetrical radiation pattern across the working band,therefore making it suitable to be used as antenna and antenna array element of mobile wireless communication base stations.展开更多
To estimate woody plant biomass stocks in different patches of forest ecosystems, total 20, 500 × 10 m (0.5 ha) sized line transects were laid in a protected area of Tripura, Northeast India. Overall, 9160 indivi...To estimate woody plant biomass stocks in different patches of forest ecosystems, total 20, 500 × 10 m (0.5 ha) sized line transects were laid in a protected area of Tripura, Northeast India. Overall, 9160 individuals were measured at ≥10 cm diameter at breast height (dbh) in 10 ha sampled area. Estimation of biomass suggested that highest coefficient for allometric relationships between density and biomass in 10 dbh classes was observed in bamboo brakes (R<sup>2</sup> = 0.90) than lowest for semi evergreen patch (R<sup>2</sup> = 0.48). The stock of carbon (C) was differ significantly along the forest patches (F = 7.01, df = 3.19;p < 0.01). Most of biomass stock (69.38%) was accumulated in lower dbh class (<30 cm) and only 23% of biomass was estimated at higher dbh classes (> 70 cm). Range of biomass stock (37.85 - 85.58 Mg ha<sup>-</sup><sup>1</sup>) was low, compared to other tropical forest ecosystems in India, which implies that the proper management is required to monitor regional ecosystem C pool.展开更多
Based on the finite element method, a numerical investigation into the bonded repair efficiency of cracked plates under in plane biaxial loadings is presented. The main considerations are: reduction in stress intensi...Based on the finite element method, a numerical investigation into the bonded repair efficiency of cracked plates under in plane biaxial loadings is presented. The main considerations are: reduction in stress intensity factor (SIF) at the crack tip, the maximum tensile stress in the composite patch and the maximum shear stress in the adhesive bond between the patch and the plate. Without the patch, a tensile or compressive stress parallel to the crack has no effect on the SIF at the crack tip. While with a composite patch, there exists coupling effect between the normal stress parallel to the crack and the SIF, and the coupling effect depends significantly on ply orientation of the patch and the biaxial stress ratio of the plate.展开更多
Bare patches in alpine meadow are the main manifestation of its degradation.The change of bare patches in an alpine meadow in the Yellow River Source Zone during 2018-2019 was studied in relation to the disturbances c...Bare patches in alpine meadow are the main manifestation of its degradation.The change of bare patches in an alpine meadow in the Yellow River Source Zone during 2018-2019 was studied in relation to the disturbances caused by plateau pika(Ochotona curzoniae)population and simulated grazing via artificial mowing both independently and interactively.The disturbance was set at three levels of high,medium and no disturbance(control group).Bare patches were mapped by from unmanned aerial vehicle(UAV)images with fine resolution of 1 cm obtained in August 2018 and August 2019 in ArcGIS.The results showed that the total area of bare patches decreased by 112.05 m2 in sub-plots devoid of pika disturbance but increased by 126.37 m2 in other subplots.The highest rate of increase is 89.02%.The individual effect of pika exceeds the joint effect of pika and mowing disturbances.The sole effect of mowing is lower than the joint effect of pika disturbance and intensive mowing,but higher than the joint influence of pika disturbance and moderate mowing.Strong pika disturbance(14 per sub-plot)caused the influence of mowing from moderate to intensive to increase by five-fold.The area of bare patches treated with moderate mowing and no pika disturbance decreased at the highest pace(-37.22%).Intensive mowing and medium density pikas(100 pikas/ha)are considered the thresholds at which the bare patches start to expand.Even if the meadow is mowed at the medium and high intensity,the area of bare patches can be significantly reduced if plateau pika population is controlled to a low level.ANOVA analysis and longterm macro-scale satellite-derived results reveal that pika disturbance is more important in causing the bare patches to change than simulated grazing.Therefore,it is more important to control the number of pikas than to reduce grazing intensity to prevent the expansion of bare patches in the degraded alpine meadow in the study area.展开更多
Global climate changes have significantly affected tree growth and forest structures and functions in some arid and semi-arid regions,which are becoming warmer and wetter.Due to natural factors such as climate and ter...Global climate changes have significantly affected tree growth and forest structures and functions in some arid and semi-arid regions,which are becoming warmer and wetter.Due to natural factors such as climate and terrain,some tree species may form different forest patches at the edges of their distribution areas.However,how forest patches of various sizes respond to climate change is unclear.In this study,we collected 203 tree cores from six different sizes of forest patches at the edge of the distribution area of Picea crassifolia Kom.in the northeast Tibetan Plateau.And we used the dendrochronology method to study the response of tree growth and resilience in different forest patches to climate change from 1961 to 2020.We simultaneously measured the contents of nonstructural carbohydrates(NSC),total nitrogen and total phosphorus of tree needles.Our results showed that the growth of trees in small-and medium-size forest patches(0.8–18.6 ha)has increased significantly.The early growing season(May–July)minimum temperature was the most important climate factor driving the growth of small-and medium-sized patch trees.The early growing season maximum temperature was the most important climate factor that inhibited the growth of trees in the largest patches(362.8 ha).The growth of individual trees in medium forest patches was better and the correlation with annual minimum temperature,maximum temperature,precipitation,actual evapotranspiration,and palmer drought severity index was stronger.The higher NSC content,stronger photosynthesis,and higher nitrogen utilization efficiency in leaves might be one of the reasons for the better growth of trees in moderate forest patches.In extreme drought years,as the forest patch area increased,the overall trend of tree growth resistance showed a unimodal pattern,with the highest at a forest patch area of 7.1 ha,while the overall trend of tree growth recovery was opposite.Therefore,we should strengthen the management of trees in large forest patches to cope with climate change.展开更多
Pose-invariant facial expression recognition(FER)is an active but challenging research topic in computer vision.Especially with the involvement of diverse observation angles,FER makes the training parameter models inc...Pose-invariant facial expression recognition(FER)is an active but challenging research topic in computer vision.Especially with the involvement of diverse observation angles,FER makes the training parameter models inconsistent from one view to another.This study develops a deep global multiple-scale and local patches attention(GMS-LPA)dual-branch network for pose-invariant FER to weaken the influence of pose variation and selfocclusion on recognition accuracy.In this research,the designed GMS-LPA network contains four main parts,i.e.,the feature extraction module,the global multiple-scale(GMS)module,the local patches attention(LPA)module,and the model-level fusion model.The feature extraction module is designed to extract and normalize texture information to the same size.The GMS model can extract deep global features with different receptive fields,releasing the sensitivity of deeper convolution layers to pose-variant and self-occlusion.The LPA module is built to force the network to focus on local salient features,which can lower the effect of pose variation and self-occlusion on recognition results.Subsequently,the extracted features are fused with a model-level strategy to improve recognition accuracy.Extensive experimentswere conducted on four public databases,and the recognition results demonstrated the feasibility and validity of the proposed methods.展开更多
Objective: To research the expression of hypoxia inducible factor-1 alpha (HIF-1 alpha) on the apoptosis and number of T lymphocyte in Peyer’s patches after severe burn on plateau in rats. Methods: Wistar rats (n = 1...Objective: To research the expression of hypoxia inducible factor-1 alpha (HIF-1 alpha) on the apoptosis and number of T lymphocyte in Peyer’s patches after severe burn on plateau in rats. Methods: Wistar rats (n = 130) were subjected to deep thickness burn injury (30% TBSA, III degree), at two different altitudes. 60 of them were given delayed fluid resuscitation (DFR, n = 30 at each altitude) 6 h after burn at different altitude;60 of them were carried out immediate fluid resuscitation (IFR, n = 30 at each altitude);10 rats were subjected to 37°C warm water as sham burn (SG, n = 10). The Peyer’s patches were harvested from the ileum of rats at different time point after burn respectively. The expression of HIF-1 alpha, CD3(+) and the apoptosis and number of T lymphocyte in Peyer’s patches were detected by tissue microarray technology and immunohistochemistry. Results: The apoptosis was higher in DFR group than that in IFR group. The increase in HIF-1 alpha expression was observed mainly on cell nucleus in T lymphocytes. The expression levels of HIF-1 alpha in Peyer’s patches were much higher in DFR group and IFR group than those in SG, and they were higher at high altitude (3848 metres) than those at lower altitude (1517 metres), and also higher in DFR group compared with IFR group (all P < 0.05). The expression levels of CD3<sup>+</sup> in Peyer’s patches were much lower in DFR group and IFR group than those in sham group, and the lowest value appeared at 12 hours after burn (all P < 0.05). Conclusion: High expression of HIF-1 alpha may induce the apoptosis of T lymphocytes in Peyer’s patches after severe burn with delayed fluid resuscitation in rats at plateau.展开更多
基金supported by the National Natural Science Foundation of China(Grants 42325404,42120104003,42204164,42474219 and U22A2006)the Chinese Meridian Project,the International Partnership Program of Chinese Academy of Sciences(Grant 183311KYSB20200003)+7 种基金Shandong Provincial Natural Science Foundation(Grants ZR2022QD077,ZR2022MD034)the Stable-Support Scientific Project of China Research Institute of Radiowave Propagation(Grant A132312191)the foundation of the National Key Laboratory of Electromagnetic Environment(Grant 6142403180204)the Chongqing Natural Science Foundation(Grants cstc2021ycjh-bgzxm0072,CSTB2023NSCQ-LZX0082)National Program on Key Basic Research Project(Grant 2022173-SD-1)The work in Norway is supported by the Research Council of Norway Grant 326039Work at UCLA has been supported by NSF grant AGS-2055192This research was supported by the International Space Science Institute(ISSI)in Bern and Beijing,through ISSI International Team project#511(Multi-Scale Magnetosphere-Ionosphere-Thermosphere Interaction).
文摘This paper is a statistical survey of Southern Hemisphere cold and hot polar cap patches,in relation to the interplanetary magnetic field(IMF)and ionospheric convection geometry.A total of 11,946 patch events were identified by Defense Meteorological Satellite Program(DMSP)F16 during the years 2011 to 2022.A temperature ratio of ion/electron temperature(T_(i)/T_(e))<0.68 is recommended to define a hot patch in the Southern Hemisphere,otherwise it is defined as a cold patch.The cold and hot patches have different dependencies on IMF clock angle,while their dependencies on IMF cone angle are similar.Both cold and hot patches appear most often on the duskside,and the distribution of cold patches gradually decreases from the dayside to the nightside,while hot patches have a higher occurrence rate near 14 and 21 magnetic local time(MLT).Moreover,we compared the key plasma characteristics of polar cap cold and hot patches in the Southern and Northern Hemispheres.The intensity of the duskside upward field-aligned current of patches in the Southern Hemisphere(SH)is stronger than that in the Northern Hemisphere(SH),which may be due to the discrepancy in conductivities between the two hemispheres,caused by the tilted dipole.In both hemispheres,the downward soft-electron energy flux of the dawnside patches is significantly greater than that of the duskside patches.
基金the Faculty of Pharmacy and the Research Institute of Rangsit University(Grant No.74/2555)for financial supports.
文摘Our work was to study the preparation,physicochemical characterization,and in vitro characteristic of Zingiber cassumunar blended patches.The Z.cassumunar blended patches incorporating Z.cassumunar Roxb.also known as Plai were prepared from chitosan and polyvinyl alcohol with glycerin as plasticizer.They were prepared by adding all ingredients in a beaker and homogeneously mixing them.Then,they were transferred into Petri-dish and dried in hot air oven.The hydrophilic nature of the Z.cassumunar blended patches was confirmed by the moisture uptake,swelling ratio,erosion,and porosity values.The FTIR,DSC,XRD,and SEM studies showed revealed blended patches with amorphous region that was homogeneously smooth and compact in both surface and cross section dimensions.They exhibited controlled the release behavior of(E)-4-(30,40-dimethoxyphenyl)but-3-en-lol(compound D)that is the main active compound in Z.cassumunar for anti-inflammation activity.However,in in vitro skin permeation study,the compound D was accumulated in newborn pig skin more than in the receptor medium.Thus,the blended patches showed the suitable entrapment and controlled release of compound D.Accordingly,we have demonstrated that such chitosan and polyvinyl alcohol formulated patches might be developed for medical use.
基金Supported by the Program for Technology Research and Development and Its Demonstration and Popularization of Beijing Vocational College of Agriculture(XY-YF-15-08)~~
文摘With the development of pharmaceutics and other disciplines theories and advanced technologies, the application of many new drug delivery systems has gradually increased in clinical veterinary. Among the many drug delivery systems, transdermal patch can maintain stable and effective plasma concentration and therapeutic effect in vivo for a long time after skin dressing delivery, which provides a safe and effective drug-delivery way for the therapy and prevention of some chronic diseases and partial analgesia in a simple and convenient way. Veterinary drug transdermal preparations have been developed both at home and abroad, and satisfactory results have been achieved in the experimental application. Based on the study of veterinary transdermal patches at home and abroad, this paper systematically describes the development and characteristics of transdermal patches, the factors affecting skin permeation and the evaluation this type of preparations in veterinary drugs.
基金National Defense Basic Foundation (Z192002A001)National Defense Monograph Foundation
文摘For the truss structure composed of active-elements with piezoelectric patches affixed to its surface,taking the mechani-cal-electric coupling effect under the action of electric loads and mechanical loads into consideration,the finite element model for static force analysis is established by using the theory of mechanics. The failure mechanism of piezoelectric elements is discussed and the failure criteria of piezoelectric elements are proposed. The expression of safety margins for the element of piezoelec...
基金‘863'High Technology R&D Project of Ministry of Science and Technology of China(Grant No.2004AA2Z3073).
文摘The objective of the present study is to examine cardiovascular protective action of a newly developed transdermal patch by incorporating bisoprolol and isosorbide dinitrate in spontaneously hypertensive rats. As the combination therapy with these two synergistic drugs at low doses through a suitable form of administration could provide optimal therapeutic benefit, we further evaluated the effects of a 42 d period of anti-hypertensive treatment in spontaneously hypertensive rats. Rats were divided into the following five groups: control (blank patch), bisoprolol fumarate tablets (BP-FT, 20.0 mg/kg, i.g.), bisoprolol transdermal patch (BP-TP, 20.0 mg/kg), isosorbide dinitrate transdermal patch (ISDN-TP, 20.0 mg/kg), and the combination of BP and ISDN in a transdermal patch at low doses (8 and 12 mg/kg, respectively). The effects of treatment were evaluated via biochemical indicators related to cardiovascular protection, structure and function. The combination therapy had synergistic anti-hypertensive effects and significantly reduced blood pressure with the benefit of controlling blood pressure variability compared to BP-FT and BP-TP. The combined treatment also reduced heart rate as well as BP-FT and BP-TP, while ISDN-TP had no evident effects on blood pressure, heart rate, and cardiovascular protection. Combination therapy was superior to BP-TP and BP-FT at increasing blood atrial natriuretic peptide and nitric oxide, while also reducing cardiac hydroxyproline and endothelin-1 with no difference in blood endothelin-1 and cardiac malondialdehyde levels. Cardiovascular remodeling differed among the groups, with the combination therapy reducing cardiac hypertrophy and the aortic media/lumen ratio. The consequential improvements in relaxation in response to cumulative concentrations of acetylcholine may explain the associated improvement in endothelial function. Combi- nation treatment with a transdermal patch exhibited a synergistic therapeutic effect. Such favorable cardiovascular effects with nitric oxide donors and β-blockade combination through a transdermal patch may provide long-term cardiovascular protection during anti-hypertensive treatment.
基金The study was supported by the State Basic Research and Development Plan of China (G2000018602)
文摘The dynamics of soil seed banks and seed movement was investigated in three bare alkali-saline patches in Songnen grassland, Northeast China, for exploring their potential role in the vegetation restoration of bare alkali-saline patches. The results showed that the seed banks and the seed movement in these patches were very similar to each other, and to some extent the seed movement was related to patch-side vegetation there. Seed movement across the soil surface of these bare alkali-saline patches was abundant and dominated by the seeds of pioneer species, such as Chloris virgata and Suaeda corniculata, which accounted for over 96% of these trapped seeds. In the contrast, soil seed banks of bare patches were extremely small, in different seasons, especially in May and June, even no any seed have been found, mainly due to lowest retaining capacity of surface soil to those abundant seed movement. Both soil seed banks and seed movement showed seasonal variation, and usually reached the maximum in October. Soil seed banks of bare alkali-saline patches, which were extremely small and difficult to recruit naturally, may inhibit speed of vegetation restoration. It is suggested that seed movement would be the potential seed source and play a potentially important role in the process of vegetation restoration of bare alkali-saline patches by enhancing the soft retaining capacity to seed movement.
基金supported by the National Natural Science Foundation of China(Nos.91839101,21774086)the Natural Science Foundation of Jiangsu Province(No.BK20180093)+4 种基金the Suzhou Municipal Science and Technology Foundation(No.SYS2018026)the Introduction Project of Clinical Medicine Expert Team for Suzhou(No.SZYJTD201704)the Project of Improvement in Clinical Trial Ability of Cardiovascular Group of the First Affiliated Hospital of Soochow University(No.201900180019)the Application Research on New Platelet Function-detecting Technology in Thrombosis Prevention(No.31010303010982)the Priority Academic Program Development of Jiangsu Higher Education。
文摘Myocardial infarction(MI)is one of the common cardiovascular diseases that occurs with a blockage in one or more of the coronary arteries to lead to the damage of the myocardium,resulting in a lifethreatening condition.To repair the damaged myocardium in MI,researchers are looking forwards to new ways to postpone the progression of myocardial injury.Cardiac patches,the scaffolds layered on the heart surface,can provide mechanical support for the infarction site and improve cardiac function by delivering various bioactive factors or cells,showing considerable curative effect in the treatment of MI.Biomaterials with certain biocompatibility and mechanical properties have received widespread attention for the application in cardiac patches.In this review,we focus on the recent progress on these biomaterialsbased cardiac patches,which could be categorized into two types according to the sources of materials including(ⅰ)natural materials and(ⅱ)synthetic materials.The major advantages and current challenges of each type are discussed and a brief perspective on the future research directions is presented.
基金supported by RR college of Pharmacy affiliated to Rajiv Gandhi University of Health Sciences,Bangalore,India(Grant No.RRCP\PCEUTICS\IHR&D\231)
文摘Objective:To achieve transbuccal release of carbamazepine by loading in unidirectional release mucoadhesive buccal patches.Methods:Buccal patches of carbamazepine with unidirectional drug release were prepared using hydroxypropyl methyl cellulose,polyvinyl alcohol,polyvinyl pyrrolidone and ethyl cellulose by solvent casting method.Water impermeable backing layer(Pidilite?Biaxially-oriented polypropylene film)of patches provided unidirectional drug release.They were evaluated for thickness,mass uniformity,surface pH and folding endurance.Six formulations FA2,FA8,FA10,FBI,FB14 and FB16(folding endurance above 250)were evaluated further for swelling studies,ex vivo mucoadhesive strength,ex vivo mucoadhesion time,in vitro drug release,ex vivo permeation,accelerated stability studies and FTIR and XRD spectral studies.Results:The ex vivo mucoadhesion time of patches ranged between 109 min(FA10)to 126 min(FB14).The ex vivo mucoadhesive force was in the range of 0.278 lo 0.479 kg/m/s.The in vitro drug release studies revealed that formulation FA8 released 84%and FB16 released 99.01%of drug in140 min.Conclusions:The prepared unidirectional buccal patches of carbamazepine provided a maximum drug release within specified mucoadhesion period and it indicates a potential alternative drug delivery system for systemic denvery of carbamazepine.
文摘We presented a 20-year-old patient with Crohn's disease (CD).Colonoscopy revealed longitudinal ulceration in the terminal ileum and rectal aphtoid ulcers.After treatment with mesalamine and total parenteral nutrition,repeat colonoscopy revealed a granular elevated area in the terminal ileum,which appeared as an irregular dome-like elevation with irregularly arranged villi on magnifying endoscopy.Biopsy specimens taken from the region showed microgranulomas and lymphoid hyperplasia,Scanning electron microscopy revealed the presence of M cells,confirming that the area corresponded to Peyer's patches.Peyer's patches by magnifying endoscopy and electron microscopy may provide insights into the pathogenesis of CD.
基金National Natural Science Foundation of China (41025001, 41130640 )We would like to thank the anonymous reviewers for their valuable and constructive comments. The authors also wish to thank the Shuai Guan-yuan and Sun Xiu-min for assistance in the field work.
文摘Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems.The dye coverage,uniform infiltration depth,maximum infiltration depth,total stained area and heterogeneous infiltration stained area were measured by two indices,the maximum infiltration depth index(MIDI)and heterogeneous infiltration index(HII),which were calculated by processing dye-stained photos.The MIDI and HII of soil under shrubs were 1.41±0.14 and 0.29±0.068,respectively,and larger than those of grass soil,1.26±0.14 and0.20±0.076.Using the MIDI,HII,field soil moisture and rainfall data,the infiltration depth and heterogeneous infiltration amount for 26 nature rainfall events were calculated.The results imply that water can infiltrate to a deeper layer beneath shrub canopy than beneath grass patches and that more water infiltration occurs beneath shrub canopy than beneath grass patches.These results are of prime importance for arid and semiarid ecosystems with a limited water supply due to high evaporation and low precipitation.
基金Natural Science Founda-tion of China(Grant 61171051 and 61771063)Plan-ning projects of Hebei provincial department(Grant 15210410)Research Fund Project of North China Institute of Aerospace Engineering(Grant BKY-2021-13)。
文摘A new dual-polarized staggered and stacked patches antenna with wide impedance band-width and high isolation is proposed.The antenna consists of two groups of radiation patches,in 7 layers,and uses the orthogonal adjacent coupling structure on staggered layer to excite a pair of linear polarization modes.Thanks to the staggered feeder mode,it has increased the isolation performance be-tween ports and compressed the transverse size of the antenna.As a result of the combination of staggered stack-up between the patches and the stepped gradient shape of the main radiating patches,it has effectively expanded the impedance bandwidth of the antenna.The proposed antenna is simulated,fabricated and measured.The staggered feeding structure effectively reduces the cross-sectional area of the antenna,and greatly improves the isolation between feeding ports.The measurement results show that the impedance bandwidths for vertical and horizontal polarization modes are 40.2%(638-960 MHz)and 40.0%(645-968 MHz)respectively when the return loss is lower than-10 dB,and the isolation between feeding ports is better than-30 dB.Meanwhile,the antenna has a stable and symmetrical radiation pattern across the working band,therefore making it suitable to be used as antenna and antenna array element of mobile wireless communication base stations.
文摘To estimate woody plant biomass stocks in different patches of forest ecosystems, total 20, 500 × 10 m (0.5 ha) sized line transects were laid in a protected area of Tripura, Northeast India. Overall, 9160 individuals were measured at ≥10 cm diameter at breast height (dbh) in 10 ha sampled area. Estimation of biomass suggested that highest coefficient for allometric relationships between density and biomass in 10 dbh classes was observed in bamboo brakes (R<sup>2</sup> = 0.90) than lowest for semi evergreen patch (R<sup>2</sup> = 0.48). The stock of carbon (C) was differ significantly along the forest patches (F = 7.01, df = 3.19;p < 0.01). Most of biomass stock (69.38%) was accumulated in lower dbh class (<30 cm) and only 23% of biomass was estimated at higher dbh classes (> 70 cm). Range of biomass stock (37.85 - 85.58 Mg ha<sup>-</sup><sup>1</sup>) was low, compared to other tropical forest ecosystems in India, which implies that the proper management is required to monitor regional ecosystem C pool.
文摘Based on the finite element method, a numerical investigation into the bonded repair efficiency of cracked plates under in plane biaxial loadings is presented. The main considerations are: reduction in stress intensity factor (SIF) at the crack tip, the maximum tensile stress in the composite patch and the maximum shear stress in the adhesive bond between the patch and the plate. Without the patch, a tensile or compressive stress parallel to the crack has no effect on the SIF at the crack tip. While with a composite patch, there exists coupling effect between the normal stress parallel to the crack and the SIF, and the coupling effect depends significantly on ply orientation of the patch and the biaxial stress ratio of the plate.
基金financially supported by the National Natural Science Foundation of China(Grant No.31872999)Project of the Science and Technology Department of Qinghai Province(Grant No.2018-ZJ781)+2 种基金Discipline Innovation and Introducing Talents Program of Higher Education Institutions(the 111 Project)(Grant No.D18013)Changjiang Scholars and Innovation Team Development plan(Grant No.IRT17R62)China Scholarship Council(Grant No.201907660003)。
文摘Bare patches in alpine meadow are the main manifestation of its degradation.The change of bare patches in an alpine meadow in the Yellow River Source Zone during 2018-2019 was studied in relation to the disturbances caused by plateau pika(Ochotona curzoniae)population and simulated grazing via artificial mowing both independently and interactively.The disturbance was set at three levels of high,medium and no disturbance(control group).Bare patches were mapped by from unmanned aerial vehicle(UAV)images with fine resolution of 1 cm obtained in August 2018 and August 2019 in ArcGIS.The results showed that the total area of bare patches decreased by 112.05 m2 in sub-plots devoid of pika disturbance but increased by 126.37 m2 in other subplots.The highest rate of increase is 89.02%.The individual effect of pika exceeds the joint effect of pika and mowing disturbances.The sole effect of mowing is lower than the joint effect of pika disturbance and intensive mowing,but higher than the joint influence of pika disturbance and moderate mowing.Strong pika disturbance(14 per sub-plot)caused the influence of mowing from moderate to intensive to increase by five-fold.The area of bare patches treated with moderate mowing and no pika disturbance decreased at the highest pace(-37.22%).Intensive mowing and medium density pikas(100 pikas/ha)are considered the thresholds at which the bare patches start to expand.Even if the meadow is mowed at the medium and high intensity,the area of bare patches can be significantly reduced if plateau pika population is controlled to a low level.ANOVA analysis and longterm macro-scale satellite-derived results reveal that pika disturbance is more important in causing the bare patches to change than simulated grazing.Therefore,it is more important to control the number of pikas than to reduce grazing intensity to prevent the expansion of bare patches in the degraded alpine meadow in the study area.
基金supported by the National Natural Science Foundation of China(Nos.31971460 and 32271646s).
文摘Global climate changes have significantly affected tree growth and forest structures and functions in some arid and semi-arid regions,which are becoming warmer and wetter.Due to natural factors such as climate and terrain,some tree species may form different forest patches at the edges of their distribution areas.However,how forest patches of various sizes respond to climate change is unclear.In this study,we collected 203 tree cores from six different sizes of forest patches at the edge of the distribution area of Picea crassifolia Kom.in the northeast Tibetan Plateau.And we used the dendrochronology method to study the response of tree growth and resilience in different forest patches to climate change from 1961 to 2020.We simultaneously measured the contents of nonstructural carbohydrates(NSC),total nitrogen and total phosphorus of tree needles.Our results showed that the growth of trees in small-and medium-size forest patches(0.8–18.6 ha)has increased significantly.The early growing season(May–July)minimum temperature was the most important climate factor driving the growth of small-and medium-sized patch trees.The early growing season maximum temperature was the most important climate factor that inhibited the growth of trees in the largest patches(362.8 ha).The growth of individual trees in medium forest patches was better and the correlation with annual minimum temperature,maximum temperature,precipitation,actual evapotranspiration,and palmer drought severity index was stronger.The higher NSC content,stronger photosynthesis,and higher nitrogen utilization efficiency in leaves might be one of the reasons for the better growth of trees in moderate forest patches.In extreme drought years,as the forest patch area increased,the overall trend of tree growth resistance showed a unimodal pattern,with the highest at a forest patch area of 7.1 ha,while the overall trend of tree growth recovery was opposite.Therefore,we should strengthen the management of trees in large forest patches to cope with climate change.
基金supported by the National Natural Science Foundation of China (No.31872399)Advantage Discipline Construction Project (PAPD,No.6-2018)of Jiangsu University。
文摘Pose-invariant facial expression recognition(FER)is an active but challenging research topic in computer vision.Especially with the involvement of diverse observation angles,FER makes the training parameter models inconsistent from one view to another.This study develops a deep global multiple-scale and local patches attention(GMS-LPA)dual-branch network for pose-invariant FER to weaken the influence of pose variation and selfocclusion on recognition accuracy.In this research,the designed GMS-LPA network contains four main parts,i.e.,the feature extraction module,the global multiple-scale(GMS)module,the local patches attention(LPA)module,and the model-level fusion model.The feature extraction module is designed to extract and normalize texture information to the same size.The GMS model can extract deep global features with different receptive fields,releasing the sensitivity of deeper convolution layers to pose-variant and self-occlusion.The LPA module is built to force the network to focus on local salient features,which can lower the effect of pose variation and self-occlusion on recognition results.Subsequently,the extracted features are fused with a model-level strategy to improve recognition accuracy.Extensive experimentswere conducted on four public databases,and the recognition results demonstrated the feasibility and validity of the proposed methods.
文摘Objective: To research the expression of hypoxia inducible factor-1 alpha (HIF-1 alpha) on the apoptosis and number of T lymphocyte in Peyer’s patches after severe burn on plateau in rats. Methods: Wistar rats (n = 130) were subjected to deep thickness burn injury (30% TBSA, III degree), at two different altitudes. 60 of them were given delayed fluid resuscitation (DFR, n = 30 at each altitude) 6 h after burn at different altitude;60 of them were carried out immediate fluid resuscitation (IFR, n = 30 at each altitude);10 rats were subjected to 37°C warm water as sham burn (SG, n = 10). The Peyer’s patches were harvested from the ileum of rats at different time point after burn respectively. The expression of HIF-1 alpha, CD3(+) and the apoptosis and number of T lymphocyte in Peyer’s patches were detected by tissue microarray technology and immunohistochemistry. Results: The apoptosis was higher in DFR group than that in IFR group. The increase in HIF-1 alpha expression was observed mainly on cell nucleus in T lymphocytes. The expression levels of HIF-1 alpha in Peyer’s patches were much higher in DFR group and IFR group than those in SG, and they were higher at high altitude (3848 metres) than those at lower altitude (1517 metres), and also higher in DFR group compared with IFR group (all P < 0.05). The expression levels of CD3<sup>+</sup> in Peyer’s patches were much lower in DFR group and IFR group than those in sham group, and the lowest value appeared at 12 hours after burn (all P < 0.05). Conclusion: High expression of HIF-1 alpha may induce the apoptosis of T lymphocytes in Peyer’s patches after severe burn with delayed fluid resuscitation in rats at plateau.