Hybrid composite materials combine different fibers in preform and take advantages of different mechanical behaviors for improving ballistic impact damage tolerances.Here we report ballistic impact damages of plain-wo...Hybrid composite materials combine different fibers in preform and take advantages of different mechanical behaviors for improving ballistic impact damage tolerances.Here we report ballistic impact damages of plain-woven laminates with different hybrids and stacking sequences.Three kinds of hybrid laminates,i.e.,carbon/Kevlar,carbon/ultra-high molecular weight polyethylene(UHMWPE),and UHMWPE/Kevlar,had been prepared and tested in ballistic penetration with fragment simulating projectiles(FSP).The residual velocities of the projectiles and impact damage morphologies of the laminates have been obtained to show impact energy absorptions for the different hybrid schemes.A microstructural model of the hybrid laminates had also been established to show impact damage mechanisms with finite element analysis(FEA).We found that the UHMWPE/Kevlar hybrid laminates with Kevlar layers as the front face have the highest energy absorption capacity,followed by the carbon/Kevlar hybrid laminates with carbon layers as the front face.The main damage modes are fiber breakages,matrix crack and interlayer delamination.The ballistic damage evolutions from the FEA results show that the major damage is shear failure for front layers,while tension failure for the back layers.We expect that the ballistic impact performance could be improved from the different hybrid schemes.展开更多
Hail is a meteorological phenomenon that directly concerns to agricultural sector in Iran. Hailstorms affect crop yield that depends on the crop species and the phonological time. In this investigation, climatological...Hail is a meteorological phenomenon that directly concerns to agricultural sector in Iran. Hailstorms affect crop yield that depends on the crop species and the phonological time. In this investigation, climatological study of hail fall has been performed through the available dataset in 118 synoptic stations across the country during a period of 20 years (1985-2004) and hail event map was drawn. After analyzing the data and considering the produced maps, regarding the number of hail occurrence in the country, the following provinces respectively illustrate the highest annual mean of hail fall;Chaharmahal-e-bakhtiari, Ilam, Tehran and Kurdistan (about 4 times/yearly). In the next step, using the statistics of the agricultural insurance affairs during 1995-2005, cultivation areas damaged by hail fall in the farms of agricultural strategic products including;irrigated and rain fed wheat, grain, rice, cotton, sugar beet and potato have been studied, and then the classified maps of hail damage have been plotted for each province and crop. The produced maps indicate that most of the damaged area by hail fall has been related to irrigated wheat crop, with an annual average of 12690.8 hectares in the whole country, then the damaged crops were ordered respectively as following: rain fed wheat, sugar beet, potato, grain, cotton and rice.展开更多
In 2010, the fracking discussion in Germany caused a number of changes in German law, which came into force in 2016.Especially the production of gas had to be regulated.With the legislation amendment, the Subsidence-A...In 2010, the fracking discussion in Germany caused a number of changes in German law, which came into force in 2016.Especially the production of gas had to be regulated.With the legislation amendment, the Subsidence-Area Mining Regulation has been revised, too.The changes expand the compensation of mining damages, especially to the extraction with drilling from the surface and underground storage.Although the Subsidence-Area Mining Regulation has been revised, the area of main influence(subsidence of 10 cm)remains to determine a relevant boundary for mining damages.The determination and prediction of this boundary above caverns are presented in this paper.In addition, further elements of ground movements and their relevance to mine damages are analyzed.The usage of the area of main influence to fix a relevant boundary for mining damages does not correspond to the relevant elements of ground movements.A limit for differences in subsidence(tilt) or horizontal changes in length should be preferred to describe the relevance of mining damages on buildings.Furthermore, this paper outlines the meaning of using the area of main influence to fix a relevant boundary for mining damages.展开更多
BACKGROUND: Some scholars believed that the neuronal injury after status epilepticus is apoptosis,the main evidence is the changes of expressions of various apoptosis releted genes,such as immediate-early gene,p53 gen...BACKGROUND: Some scholars believed that the neuronal injury after status epilepticus is apoptosis,the main evidence is the changes of expressions of various apoptosis releted genes,such as immediate-early gene,p53 gene and genes of bcl-2 family,etc.But there is still no ultrastructural evidence for apoptosis.OBJECTIVE: To observe the ultrastructural damages of mitochondrion and nucleus and the changes of caspase expression in neurons of hippocampal CA3 region in rats with status epilepticus induced by kainic acid.DESIGN: A randomized controlled study.SETTING: Department of Anesthesiology and Department of Neurology,Qilu Hospital of Shandong University.MATERIALS: Seventy-five adult male Wistar rats of 250-300 g.clean degree,were provided by the experimental animal center of Shandong University.Kainic acid was purchased from Sigma Company (USA);rabbit anti-rat polyclonal antibody caspase-3 from Santa Cruz Company(USA).METHODS:The experiments were carried out in the Department of Anesthesiology,Qilu Hospital of Shandong University from October 2005 to February 2006.①The 75 rats were randomly divided into experimental group (n=45)and control group(n=30).②Model establishment,convulsion grading and the judging standards for status epilepticus:Rats in the experimental group were given intraperitoneal injection of kainic acid(10 mg/kg),and those in the control group were injected with saline of the same volume.The time of seizure was recorded and their behavioral manifestations were observed,and the seizure was terminated by intraperitoneal injection of diazepam(10 mg/kg).③Observation under electron microscope:At 3, 12 and 24 hours after status epilepticus respectively,bilateral hippocampal tissues were taken out,semithin sections of about 75 nm were prepared after fixation,dehydration and embedding,and then observed under H-800 transmission electron microscope.④Immunohistochemical detection:Bilateral hippocampi were removed at 3,12 and 24 hours after status epilepticus respectively,the fixation,dehydration,transparence,wax immersion and embedding were performed,then serial sections of CA3 region were immunohistochemically determined by the SABC method.Leica QWinV3 image analytical software was applied,then the average number and average gray value of positive cells were calculated.MAIN OUTCOME MEASURES:Results of observation under electron microscope,that of immunohistochemical staining of neurons in hippocampal CA3 region;Comparison of number of caspase-3 positive cells and gray value.RESULTS: All the 75 Wistar rats were involved in the analysis of results.①Results of observation under electron microscope:At 3 hours after status epilepticus,swelling crista and membranous disintegration were observed under electron microscope.At 24 hours,obvious nuclear changes occurred,and manifested as the side-aggegation of chromatins.②Results of immunohistochemical detection:In the experimental group,the number of caspase-3 positive cells at 3 hours after status epilepticus had no obvious difference as compared with that in the control group(P＞0.05):At 12 hours,the number and gray value of caspase-3 positive cells in the experimental group were higher than those in the control group (10.49±0.68 vs.5.33±0.43;45.57±2.27 vs,19.79±0.33,P＜0.05),the same results were also observed at 24 hours(37.36±0.57 vs.5.12±0.47;115.24±1.22 vs.18.73±0.42,P＜0.01).CONCLUSION:In the rat models of status epilepticus induced by kainic acid,mitochondrial damage was earlier than the increase of caspase-3 expression and nuclear changes,which suggested that mitochondrion was the key link for the neuronal death after status epilepticus.展开更多
A number of devastating flood events have oc-curred in the various river basins of Turkey in the last decade. Because floods caused deaths, suffering and extensive damages to both public and private properties in the ...A number of devastating flood events have oc-curred in the various river basins of Turkey in the last decade. Because floods caused deaths, suffering and extensive damages to both public and private properties in the flood areas, the government had to most of the damage in addi-tion to losing significant revenues due to the consequences of costly social and economic disruption. On the other hand, some social structures such as socioeconomic activities, land-use patterns and hydro-morphological processes are destroyed. Whereas flood control structures are considered as one of the basic strategies that can reduce flood damages and in this context flood protection planning should consider the full range of the hazard mitigation activities. In Turkey, between 1945 and 1990, 737 flooding events were occurred and at least 830 people were killed. In 1998, there was a major flooding in Zonguldak-Bartin region located on north of Turkey. Due to this devastated flooding, people lost their life and numbers of engineer-ing structures built on the river and surrounding area were totally destroyed or heavily damaged. Both side of the canal were covered with muddy soil having 0.10-0.15 m thickness. Cleaning up process took sometimes in the region. In this paper, all these subjects have been investigated in the basin and some engineering proposals have been presented.展开更多
Objective: To explore the effect of lipoic acid on oxidative stress and damages to sensory nerve subsets in patients with diabetic peripheral neuropathy. Methods: A total of 150 patients with diabetic peripheral neuro...Objective: To explore the effect of lipoic acid on oxidative stress and damages to sensory nerve subsets in patients with diabetic peripheral neuropathy. Methods: A total of 150 patients with diabetic peripheral neuropathy who had received treatment in the Hospital between January 2017 and July 2018 were selected. The patients were randomly divided into two groups, with 75 cases in each group. The control group was treated with Xueshuangtong Injection and Kallikrein, and the observation group was treated with lipoic acid plus medicines given to the control group. The nerve conduction velocity, blood pressure and blood glucose, serum lipids, and serum inflammatory factors were compared between the two groups. Results: The CPT values of the median nerve-ulnar nerves, bilateral superficial peroneal nerves and deep peroneal nerves in the observation group at 5 Hz, 250 Hz, and 2000 Hz were lower than those in the control group, and the difference was statistically significant. After treatment, the SOD in the observation group was higher than that in the control group, and the MDA and Hs-CRP were lower than those in the control group, where the difference was statistically significant. After treatment, the levels of blood pressure and blood glucose in the observation group were lower than those in the control group, and the difference was statistically significant. After treatment, LDL-C, TC, and TG in the observation group were lower than those in the control group, and HDL-C was higher than that in the control group. The difference was statistically significant. Conclusion: For patients with type 2 diabetes, lipoic acid can help improve the clinical treatment, which can improve the levels of blood glucose, blood pressure and blood lipid, increase nerve conduction velocity, and reduce the damage to sensory nerve subgroup.展开更多
Accurate seismic assessment and proper aseismic design of underground structures require a comprehensive understanding of seismic performance and response of underground structures under earthquake force.In order to u...Accurate seismic assessment and proper aseismic design of underground structures require a comprehensive understanding of seismic performance and response of underground structures under earthquake force.In order to understand the seismic behavior of tunnels during an earthquake,a wide collection of case histories has been reviewed from the available literature with respect to damage classification,to discuss the possible causes of damage,such as earthquake parameters,structural form and geological conditions.In addition,a case of Tawarayama tunnel subjected to the 2016 Kumamoto earthquake is studied.Discussion on the possible influence factors aims at improving the performancebased aseismic design of tunnels.Finally,restoration design criterion and methods are presented taking Tawarayama tunnel as an example.展开更多
A large number of buildings were seriously damaged or collapsed in the "5.12" Wenchuan earthquake. Based on field surveys and studies of damage to different types of buildings, seismic design codes have been...A large number of buildings were seriously damaged or collapsed in the "5.12" Wenchuan earthquake. Based on field surveys and studies of damage to different types of buildings, seismic design codes have been updated. This paper briefly summarizes some of the major revisions that have been incorporated into the "Standard for classification of seismic protection of building constructions GB50223-2008" and "Code for Seismic Design of Buildings GB50011-2001." The definition of seismic fortification class for buildings has been revisited, and as a result, the seismic classifications for schools, hospitals and other buildings that hold large populations such as evacuation shelters and information centers have been upgraded in the GB50223-2008 Code. The main aspects of the revised GB50011-2001 code include: (a) modification of the seismic intensity specified for the Provinces of Sichuan, Shanxi and Gansu; (b) basic conceptual design for retaining walls and building foundations in mountainous areas; (c) regularity of building configuration; (d) integration of masonry structures and precast RC floors; (e) requirements for calculating and detailing stair shafts; and (f) limiting the use of single-bay RC frame structures. Some significant examples of damage in the epicenter areas are provided as a reference in the discussion on the consequences of collapse, the importance of duplicate structural systems, and the integration of RC and masonry structures.展开更多
Background:Nicotine administration can generate severe oxidative stress and lipid peroxidation.Royal jelly,with its antioxidant properties,acts as a scavenger of reactive oxygen species.This study describes the apithe...Background:Nicotine administration can generate severe oxidative stress and lipid peroxidation.Royal jelly,with its antioxidant properties,acts as a scavenger of reactive oxygen species.This study describes the apitherapy effects of royal jelly on testicular damage following nicotine administration.Methods:Forty-eight male BALB/c mice were divided into 8 groups(n=6):saline,3 different doses of royal jelly(100,150,and 200 mg/kg body weight(BW)per day),nicotine(1.5 mg/kg),and 3 different groups of Nic+Roy(1.5 mg/kg of Nic+100,150,and 200 mg/kg BW per day of royal jelly).Nicotine was administrated intraperitoneally,and royal jelly was prescribed orally for 10 consecutive days.Serum levels of hormones(testosterone,luteinizing hormone,and follicle-stimulating hormone),total antioxidant capacity,nitric oxide(NO)status,malondialdehyde levels,sperm DNA fragmentation,sperm parameters,histopathological changes(H&E staining),immunohistochemistry against apoptotic proteins,and gene expression of Bcl-2,p53,Caspase-3,and Nrf2(real-time PCR)were assessed to evaluate the molecular and histological changes.Results:Hormone levels,sperm parameters,and status of antioxidants were decreased significantly(p<.05)following nicotine administration.Moreover,royal jelly treatment normalized hormonal and antioxidant characteristics,decreased apoptotic gene expression,increased Nfr2 gene expression,and restored histopathological alteration to the physiological status significantly(p<.05).Conclusion:Royal jelly upregulates the antioxidant status,inhibits the mitochondrialdependent apoptosis pathway,and increases the rate of proliferation.This therapeutic agent effectively protected the testis against nicotine-associated damages by antioxidant and anti-apoptotic effects.展开更多
DNA damage is one of the most important consequences of oxidative stress in the cells. If DNA repair is unable to modify these inducible DNA damages, genomic instability may lead to mutation, cancer, aging and many ot...DNA damage is one of the most important consequences of oxidative stress in the cells. If DNA repair is unable to modify these inducible DNA damages, genomic instability may lead to mutation, cancer, aging and many other diseases. Single cell gel electrophoresis or comet assay is a common and versatile method to quantify these types of DNA damages. DNA damages induced by hydrogen peroxide(H_2O_2) are one of the proper models for measurement of protective ability of different compounds. So the main aim of this review is to provide an overview about protection ability of medicinal plants and their potential mechanism against H_2O_2 induced DNA damages. In this review, relevant researches on the effect of medicinal plants on DNA damages induced by H_2O_2 and possible molecular mechanisms are discussed.It seems that, medicinal plants are considered as therapeutic key factors to protect DNA from consequences caused by oxidative stress. Sufficient in vitro evidences introduce them as DNA protective agents through different mechanisms including antioxidant activity and some other cellular mechanisms. Moreover, in order to correlate the antigenotoxicity effects with their potential antioxidant property, most of medicinal plants were evaluated in term of antioxidant activity using standard methods. This review highlights the preventive effects of herbal medicine against oxidative DNA damages as well as provides rational possibility to engage them in animal studies and future clinical investigations.展开更多
During the last four decades, reinforced-concrete structure failures have been happening widely for many reasons, such as increased service loads, war accidents, fire, and durability problems. The economic losses due ...During the last four decades, reinforced-concrete structure failures have been happening widely for many reasons, such as increased service loads, war accidents, fire, and durability problems. The economic losses due to those failures are very high. An expert system is an interactive computer-based decision tool that uses both facts and heuristics to solve difficult problems based on knowledge acquired from experts. To realize these requirements, a logic programming visual basic language is used together with visual diagnosis. The expert system, Diagnosis of Fire-Caused Damages to Reinforced-Concrete Tunnel Lining (DFCDRCTL) was developed in this work for diagnosing the annual damages caused by fire. The program is used as an alternative of a human expert to make annual technical decisions in diagnosing fire damages at the second reinforced-concrete tunnel lining segment. It is concluded that the proposed DFCDRCTL expert system is easy to use, and is fast and helpful for engineers.展开更多
This paper is a short introduction to the common type of damages in composite structures and different ways of their inspection. Due to the high increase of interest in composite materials in past decades and their us...This paper is a short introduction to the common type of damages in composite structures and different ways of their inspection. Due to the high increase of interest in composite materials in past decades and their usage in different structures, there is a need to discuss the damage types in them along with different ways of inspection. This paper provides a short review of these facts in order to fill out the gap that there is in the literature. Major emphasis is placed on the damage types and their mechanisms and inspection methods, mostly focused on wave propagation based structural health monitoring (SHM).展开更多
Snow damage on natural stands is an important problem concerning mountainous forest management.In the present research,the frequency and intensity of heavy snow damage on natural stands and the relationship of damages...Snow damage on natural stands is an important problem concerning mountainous forest management.In the present research,the frequency and intensity of heavy snow damage on natural stands and the relationship of damages with characteristics of trees,stand and topography were studied in mountainous forests of northern Iran.A systematic sampling design was applied to the study area(140 ha),with 122 circular plots.The grid dimension was100 m and each plot area was 1000 m^2.The four types of snow damage to trees include:crown damage(8.6%),stem breakage(5.4%),uprooting(3.2%),and bending(1.4%).The frequency of crown damage grew with an increase inthe diameter at breast height(DBH),while the frequency of stem breakage,uprooting and bending decreased with an increase the DBH.The frequency of crown damage,stem breakage,and total damages was related to tree species(p<0.01).Not all tree species were equally susceptible to snow damage.The amount of damage grew with increasing elevation and slope angle and decreased with increasing soil depth.Young trees(DBH<25 cm)were more susceptible to snow damage than other trees.Snow damage decreased by as the trees in the stand became more mixed in age.The susceptibility of trees to snow damage increased by height and slenderness coefficient.With adequate silvicultural operation,snow damage can be reduced to a minimum level in these natural forests.展开更多
Two complementary types NPN and PNP of bipolar junction transistors(BJTs) were exposed to high dose of neutrons and gamma rays. The change in the base and collector currents, minority carriers lifetime, and current ga...Two complementary types NPN and PNP of bipolar junction transistors(BJTs) were exposed to high dose of neutrons and gamma rays. The change in the base and collector currents, minority carriers lifetime, and current gain factor β with respect to the dose were analyzed. The contributions of the base current according to the defect types were also reported.It was declared that the radiation effect of neutrons was almost similar between the two transistor types, this effect at high dose may decrease the value of β to less than one. The Messenger-Spratt equation was used to describe the experimental results in this case. However, the experimental data demonstrated that the effect of gamma rays was generally higher on NPN than PNP transistors. This is mainly attributed to the difference in the behavior of the trapped positive charges in the SiO_2 layers. Meanwhile, this difference tends to be small for high gamma dose.展开更多
Neurodegenerative diseases are a class of chronic and complex disorders featuring progressive loss of neurons in distinct brain areas.The mechanisms responsible for the disease progression in neurodegeneration are not...Neurodegenerative diseases are a class of chronic and complex disorders featuring progressive loss of neurons in distinct brain areas.The mechanisms responsible for the disease progression in neurodegeneration are not fully illustrated.In this observational study,we have examined diverse biochemical parameters in the caudate and putamen of patients with Lewy body diseases(LBDs)and Alzheimer disease(AD),shedding some light on the involvement of oxidative damage and neuroinflammation in advanced neurodegeneration.We performed Spearman and Mantel-Cox analyses to investigate how oxidative stress and neuroinflammation exert comprehensive effects on disease progression and survival.Disease progression in LBDs correlated positively with poly(ADP-Ribose)and triggering receptors expressed on myeloid cell 2 levels in the striatum of LBD cohorts,indicating that potential parthanatos was a dominant feature of worsening disease progression and might contribute to switching microglial inflammatory phenotypes.Disease progression in AD corresponds negatively with 8-oxo-7,8-dihydro-2′-deoxyguanosine(8-oxo-d G)and myeloperoxidase concentrations in the striatum,suggesting that possible mitochondria dysfunction may be involved in the progression of AD via a mechanism ofβ-amyloid entering the mitochondria and subsequent free radicals generation.Patients with lower striatal 8-oxo-d G and myeloperoxidase levels had a survival advantage in AD.The age of onset also affected disease progression.Tissue requests for the postmortem biochemistry,genetics,and autoradiography studies were approved by the Washington University Alzheimer's Disease Research Center(ADRC)Biospecimens Committee(ethics approval reference number:T1705,approval date:August 6,2019).Recombinant DNA and Hazardous Research Materials were approved by the Washington University Environmental Health&Safety Biological Safety Committee(approval code:3739,approval date:February 25,2020).Radioactive Material Authorization was approved by the Washington University Environmental Health&Safety Radiation Safety Committee(approval code:1056,approval date:September 18,2019).展开更多
The properties of oil and gas formation could be significantly damaged during drilling and completion operations as a result of mud invasion,fluid incompatibility and interaction with rock minerals.This paper presents...The properties of oil and gas formation could be significantly damaged during drilling and completion operations as a result of mud invasion,fluid incompatibility and interaction with rock minerals.This paper presents a systematic method for evaluating formation damage during filter cake deposition(primary damage)and removal process(secondary damage).The role of primary damage in the evolution of secondary damage was also investigated.The interaction of the filter cake solvent(chelating agent solution)with the rock samples was implemented through core flooding experiment.Nuclear Magnetic Resonance(NMR)was used to evaluate the properties of the rock sample,pre and post filter cake deposition and removal processes.The results show that secondary damaged is a strong function of the location and the intensity of the primary damage.The rock type and its pore structure also play important roles in both primary and secondary damage.The extent of secondary damage depends on the amount of barium sulphate deposited during primary damage.The chelating agent used to dissolve the barites in sandstones,deposited the barite in the small pores while it enlarges the bigger pores.In contrast,the chelating agent in the carbonate samples had multiple barite deposition points.展开更多
In connection with the design of floating wind turbines,stochastic dynamic analysis is a critical task considering nonlinear wind and wave forces.To study the random structural responses of a newly designed submerged ...In connection with the design of floating wind turbines,stochastic dynamic analysis is a critical task considering nonlinear wind and wave forces.To study the random structural responses of a newly designed submerged tension leg platform(STLP)wind turbine,a set of dynamic simulations and comparison analysis with the MIT/NREL TLP wind turbine are carried out.The signal filter method is used to evaluate the mean and standard deviations of the structural response.Furthermore,the extreme responses are estimated by using the mean upcrossing rate method.The fatigue damages for blade root,tower,and mooring line are also studied according to the simulated time-series.The results and comparison analysis show that the STLP gives small surge and pitch motions and mooring line tensions in operational sea states due to the small water-plane area.Additionally,in severe sea states,the STLP gives lower extreme values of platform pitch,slightly larger surge and heave motions and better towerbase and mooring line fatigue performances than those of the MIT/NREL TLP.It is found that the STLP wind turbine has good performances in structural responses and could be a potential type for exploiting the wind resources located in deep waters.展开更多
文摘Hybrid composite materials combine different fibers in preform and take advantages of different mechanical behaviors for improving ballistic impact damage tolerances.Here we report ballistic impact damages of plain-woven laminates with different hybrids and stacking sequences.Three kinds of hybrid laminates,i.e.,carbon/Kevlar,carbon/ultra-high molecular weight polyethylene(UHMWPE),and UHMWPE/Kevlar,had been prepared and tested in ballistic penetration with fragment simulating projectiles(FSP).The residual velocities of the projectiles and impact damage morphologies of the laminates have been obtained to show impact energy absorptions for the different hybrid schemes.A microstructural model of the hybrid laminates had also been established to show impact damage mechanisms with finite element analysis(FEA).We found that the UHMWPE/Kevlar hybrid laminates with Kevlar layers as the front face have the highest energy absorption capacity,followed by the carbon/Kevlar hybrid laminates with carbon layers as the front face.The main damage modes are fiber breakages,matrix crack and interlayer delamination.The ballistic damage evolutions from the FEA results show that the major damage is shear failure for front layers,while tension failure for the back layers.We expect that the ballistic impact performance could be improved from the different hybrid schemes.
文摘Hail is a meteorological phenomenon that directly concerns to agricultural sector in Iran. Hailstorms affect crop yield that depends on the crop species and the phonological time. In this investigation, climatological study of hail fall has been performed through the available dataset in 118 synoptic stations across the country during a period of 20 years (1985-2004) and hail event map was drawn. After analyzing the data and considering the produced maps, regarding the number of hail occurrence in the country, the following provinces respectively illustrate the highest annual mean of hail fall;Chaharmahal-e-bakhtiari, Ilam, Tehran and Kurdistan (about 4 times/yearly). In the next step, using the statistics of the agricultural insurance affairs during 1995-2005, cultivation areas damaged by hail fall in the farms of agricultural strategic products including;irrigated and rain fed wheat, grain, rice, cotton, sugar beet and potato have been studied, and then the classified maps of hail damage have been plotted for each province and crop. The produced maps indicate that most of the damaged area by hail fall has been related to irrigated wheat crop, with an annual average of 12690.8 hectares in the whole country, then the damaged crops were ordered respectively as following: rain fed wheat, sugar beet, potato, grain, cotton and rice.
文摘In 2010, the fracking discussion in Germany caused a number of changes in German law, which came into force in 2016.Especially the production of gas had to be regulated.With the legislation amendment, the Subsidence-Area Mining Regulation has been revised, too.The changes expand the compensation of mining damages, especially to the extraction with drilling from the surface and underground storage.Although the Subsidence-Area Mining Regulation has been revised, the area of main influence(subsidence of 10 cm)remains to determine a relevant boundary for mining damages.The determination and prediction of this boundary above caverns are presented in this paper.In addition, further elements of ground movements and their relevance to mine damages are analyzed.The usage of the area of main influence to fix a relevant boundary for mining damages does not correspond to the relevant elements of ground movements.A limit for differences in subsidence(tilt) or horizontal changes in length should be preferred to describe the relevance of mining damages on buildings.Furthermore, this paper outlines the meaning of using the area of main influence to fix a relevant boundary for mining damages.
文摘BACKGROUND: Some scholars believed that the neuronal injury after status epilepticus is apoptosis,the main evidence is the changes of expressions of various apoptosis releted genes,such as immediate-early gene,p53 gene and genes of bcl-2 family,etc.But there is still no ultrastructural evidence for apoptosis.OBJECTIVE: To observe the ultrastructural damages of mitochondrion and nucleus and the changes of caspase expression in neurons of hippocampal CA3 region in rats with status epilepticus induced by kainic acid.DESIGN: A randomized controlled study.SETTING: Department of Anesthesiology and Department of Neurology,Qilu Hospital of Shandong University.MATERIALS: Seventy-five adult male Wistar rats of 250-300 g.clean degree,were provided by the experimental animal center of Shandong University.Kainic acid was purchased from Sigma Company (USA);rabbit anti-rat polyclonal antibody caspase-3 from Santa Cruz Company(USA).METHODS:The experiments were carried out in the Department of Anesthesiology,Qilu Hospital of Shandong University from October 2005 to February 2006.①The 75 rats were randomly divided into experimental group (n=45)and control group(n=30).②Model establishment,convulsion grading and the judging standards for status epilepticus:Rats in the experimental group were given intraperitoneal injection of kainic acid(10 mg/kg),and those in the control group were injected with saline of the same volume.The time of seizure was recorded and their behavioral manifestations were observed,and the seizure was terminated by intraperitoneal injection of diazepam(10 mg/kg).③Observation under electron microscope:At 3, 12 and 24 hours after status epilepticus respectively,bilateral hippocampal tissues were taken out,semithin sections of about 75 nm were prepared after fixation,dehydration and embedding,and then observed under H-800 transmission electron microscope.④Immunohistochemical detection:Bilateral hippocampi were removed at 3,12 and 24 hours after status epilepticus respectively,the fixation,dehydration,transparence,wax immersion and embedding were performed,then serial sections of CA3 region were immunohistochemically determined by the SABC method.Leica QWinV3 image analytical software was applied,then the average number and average gray value of positive cells were calculated.MAIN OUTCOME MEASURES:Results of observation under electron microscope,that of immunohistochemical staining of neurons in hippocampal CA3 region;Comparison of number of caspase-3 positive cells and gray value.RESULTS: All the 75 Wistar rats were involved in the analysis of results.①Results of observation under electron microscope:At 3 hours after status epilepticus,swelling crista and membranous disintegration were observed under electron microscope.At 24 hours,obvious nuclear changes occurred,and manifested as the side-aggegation of chromatins.②Results of immunohistochemical detection:In the experimental group,the number of caspase-3 positive cells at 3 hours after status epilepticus had no obvious difference as compared with that in the control group(P＞0.05):At 12 hours,the number and gray value of caspase-3 positive cells in the experimental group were higher than those in the control group (10.49±0.68 vs.5.33±0.43;45.57±2.27 vs,19.79±0.33,P＜0.05),the same results were also observed at 24 hours(37.36±0.57 vs.5.12±0.47;115.24±1.22 vs.18.73±0.42,P＜0.01).CONCLUSION:In the rat models of status epilepticus induced by kainic acid,mitochondrial damage was earlier than the increase of caspase-3 expression and nuclear changes,which suggested that mitochondrion was the key link for the neuronal death after status epilepticus.
文摘A number of devastating flood events have oc-curred in the various river basins of Turkey in the last decade. Because floods caused deaths, suffering and extensive damages to both public and private properties in the flood areas, the government had to most of the damage in addi-tion to losing significant revenues due to the consequences of costly social and economic disruption. On the other hand, some social structures such as socioeconomic activities, land-use patterns and hydro-morphological processes are destroyed. Whereas flood control structures are considered as one of the basic strategies that can reduce flood damages and in this context flood protection planning should consider the full range of the hazard mitigation activities. In Turkey, between 1945 and 1990, 737 flooding events were occurred and at least 830 people were killed. In 1998, there was a major flooding in Zonguldak-Bartin region located on north of Turkey. Due to this devastated flooding, people lost their life and numbers of engineer-ing structures built on the river and surrounding area were totally destroyed or heavily damaged. Both side of the canal were covered with muddy soil having 0.10-0.15 m thickness. Cleaning up process took sometimes in the region. In this paper, all these subjects have been investigated in the basin and some engineering proposals have been presented.
文摘Objective: To explore the effect of lipoic acid on oxidative stress and damages to sensory nerve subsets in patients with diabetic peripheral neuropathy. Methods: A total of 150 patients with diabetic peripheral neuropathy who had received treatment in the Hospital between January 2017 and July 2018 were selected. The patients were randomly divided into two groups, with 75 cases in each group. The control group was treated with Xueshuangtong Injection and Kallikrein, and the observation group was treated with lipoic acid plus medicines given to the control group. The nerve conduction velocity, blood pressure and blood glucose, serum lipids, and serum inflammatory factors were compared between the two groups. Results: The CPT values of the median nerve-ulnar nerves, bilateral superficial peroneal nerves and deep peroneal nerves in the observation group at 5 Hz, 250 Hz, and 2000 Hz were lower than those in the control group, and the difference was statistically significant. After treatment, the SOD in the observation group was higher than that in the control group, and the MDA and Hs-CRP were lower than those in the control group, where the difference was statistically significant. After treatment, the levels of blood pressure and blood glucose in the observation group were lower than those in the control group, and the difference was statistically significant. After treatment, LDL-C, TC, and TG in the observation group were lower than those in the control group, and HDL-C was higher than that in the control group. The difference was statistically significant. Conclusion: For patients with type 2 diabetes, lipoic acid can help improve the clinical treatment, which can improve the levels of blood glucose, blood pressure and blood lipid, increase nerve conduction velocity, and reduce the damage to sensory nerve subgroup.
基金funded by Japan Society for the Promotion of Science(JSPS)Grant-in-Aid for Scientific Research(Grant No.17H03506)JSPS-NSFC Bilateral Joint Research Project,Japan。
文摘Accurate seismic assessment and proper aseismic design of underground structures require a comprehensive understanding of seismic performance and response of underground structures under earthquake force.In order to understand the seismic behavior of tunnels during an earthquake,a wide collection of case histories has been reviewed from the available literature with respect to damage classification,to discuss the possible causes of damage,such as earthquake parameters,structural form and geological conditions.In addition,a case of Tawarayama tunnel subjected to the 2016 Kumamoto earthquake is studied.Discussion on the possible influence factors aims at improving the performancebased aseismic design of tunnels.Finally,restoration design criterion and methods are presented taking Tawarayama tunnel as an example.
基金National Natural Science Foundation of China Under Grant No.50439010 NSFC and Korea Science and Engineering Foundation Under Grant No.50811140341
文摘A large number of buildings were seriously damaged or collapsed in the "5.12" Wenchuan earthquake. Based on field surveys and studies of damage to different types of buildings, seismic design codes have been updated. This paper briefly summarizes some of the major revisions that have been incorporated into the "Standard for classification of seismic protection of building constructions GB50223-2008" and "Code for Seismic Design of Buildings GB50011-2001." The definition of seismic fortification class for buildings has been revisited, and as a result, the seismic classifications for schools, hospitals and other buildings that hold large populations such as evacuation shelters and information centers have been upgraded in the GB50223-2008 Code. The main aspects of the revised GB50011-2001 code include: (a) modification of the seismic intensity specified for the Provinces of Sichuan, Shanxi and Gansu; (b) basic conceptual design for retaining walls and building foundations in mountainous areas; (c) regularity of building configuration; (d) integration of masonry structures and precast RC floors; (e) requirements for calculating and detailing stair shafts; and (f) limiting the use of single-bay RC frame structures. Some significant examples of damage in the epicenter areas are provided as a reference in the discussion on the consequences of collapse, the importance of duplicate structural systems, and the integration of RC and masonry structures.
基金funded by Kermanshah University of Medical Sciences(grant no.96067)。
文摘Background:Nicotine administration can generate severe oxidative stress and lipid peroxidation.Royal jelly,with its antioxidant properties,acts as a scavenger of reactive oxygen species.This study describes the apitherapy effects of royal jelly on testicular damage following nicotine administration.Methods:Forty-eight male BALB/c mice were divided into 8 groups(n=6):saline,3 different doses of royal jelly(100,150,and 200 mg/kg body weight(BW)per day),nicotine(1.5 mg/kg),and 3 different groups of Nic+Roy(1.5 mg/kg of Nic+100,150,and 200 mg/kg BW per day of royal jelly).Nicotine was administrated intraperitoneally,and royal jelly was prescribed orally for 10 consecutive days.Serum levels of hormones(testosterone,luteinizing hormone,and follicle-stimulating hormone),total antioxidant capacity,nitric oxide(NO)status,malondialdehyde levels,sperm DNA fragmentation,sperm parameters,histopathological changes(H&E staining),immunohistochemistry against apoptotic proteins,and gene expression of Bcl-2,p53,Caspase-3,and Nrf2(real-time PCR)were assessed to evaluate the molecular and histological changes.Results:Hormone levels,sperm parameters,and status of antioxidants were decreased significantly(p<.05)following nicotine administration.Moreover,royal jelly treatment normalized hormonal and antioxidant characteristics,decreased apoptotic gene expression,increased Nfr2 gene expression,and restored histopathological alteration to the physiological status significantly(p<.05).Conclusion:Royal jelly upregulates the antioxidant status,inhibits the mitochondrialdependent apoptosis pathway,and increases the rate of proliferation.This therapeutic agent effectively protected the testis against nicotine-associated damages by antioxidant and anti-apoptotic effects.
文摘DNA damage is one of the most important consequences of oxidative stress in the cells. If DNA repair is unable to modify these inducible DNA damages, genomic instability may lead to mutation, cancer, aging and many other diseases. Single cell gel electrophoresis or comet assay is a common and versatile method to quantify these types of DNA damages. DNA damages induced by hydrogen peroxide(H_2O_2) are one of the proper models for measurement of protective ability of different compounds. So the main aim of this review is to provide an overview about protection ability of medicinal plants and their potential mechanism against H_2O_2 induced DNA damages. In this review, relevant researches on the effect of medicinal plants on DNA damages induced by H_2O_2 and possible molecular mechanisms are discussed.It seems that, medicinal plants are considered as therapeutic key factors to protect DNA from consequences caused by oxidative stress. Sufficient in vitro evidences introduce them as DNA protective agents through different mechanisms including antioxidant activity and some other cellular mechanisms. Moreover, in order to correlate the antigenotoxicity effects with their potential antioxidant property, most of medicinal plants were evaluated in term of antioxidant activity using standard methods. This review highlights the preventive effects of herbal medicine against oxidative DNA damages as well as provides rational possibility to engage them in animal studies and future clinical investigations.
基金Funded by the National Natural Science Foundation of China under Grant No. 51278427the Program for New Century Excellent Talents in Universities under Grant No. 10-0667+1 种基金the National Natural Science Foundation of High Iron Mutual Funds (No. U1134208)the Fundamental Research Funds for the Central Universities (No. SWJTU11ZT33)
文摘During the last four decades, reinforced-concrete structure failures have been happening widely for many reasons, such as increased service loads, war accidents, fire, and durability problems. The economic losses due to those failures are very high. An expert system is an interactive computer-based decision tool that uses both facts and heuristics to solve difficult problems based on knowledge acquired from experts. To realize these requirements, a logic programming visual basic language is used together with visual diagnosis. The expert system, Diagnosis of Fire-Caused Damages to Reinforced-Concrete Tunnel Lining (DFCDRCTL) was developed in this work for diagnosing the annual damages caused by fire. The program is used as an alternative of a human expert to make annual technical decisions in diagnosing fire damages at the second reinforced-concrete tunnel lining segment. It is concluded that the proposed DFCDRCTL expert system is easy to use, and is fast and helpful for engineers.
文摘This paper is a short introduction to the common type of damages in composite structures and different ways of their inspection. Due to the high increase of interest in composite materials in past decades and their usage in different structures, there is a need to discuss the damage types in them along with different ways of inspection. This paper provides a short review of these facts in order to fill out the gap that there is in the literature. Major emphasis is placed on the damage types and their mechanisms and inspection methods, mostly focused on wave propagation based structural health monitoring (SHM).
文摘Snow damage on natural stands is an important problem concerning mountainous forest management.In the present research,the frequency and intensity of heavy snow damage on natural stands and the relationship of damages with characteristics of trees,stand and topography were studied in mountainous forests of northern Iran.A systematic sampling design was applied to the study area(140 ha),with 122 circular plots.The grid dimension was100 m and each plot area was 1000 m^2.The four types of snow damage to trees include:crown damage(8.6%),stem breakage(5.4%),uprooting(3.2%),and bending(1.4%).The frequency of crown damage grew with an increase inthe diameter at breast height(DBH),while the frequency of stem breakage,uprooting and bending decreased with an increase the DBH.The frequency of crown damage,stem breakage,and total damages was related to tree species(p<0.01).Not all tree species were equally susceptible to snow damage.The amount of damage grew with increasing elevation and slope angle and decreased with increasing soil depth.Young trees(DBH<25 cm)were more susceptible to snow damage than other trees.Snow damage decreased by as the trees in the stand became more mixed in age.The susceptibility of trees to snow damage increased by height and slenderness coefficient.With adequate silvicultural operation,snow damage can be reduced to a minimum level in these natural forests.
文摘Two complementary types NPN and PNP of bipolar junction transistors(BJTs) were exposed to high dose of neutrons and gamma rays. The change in the base and collector currents, minority carriers lifetime, and current gain factor β with respect to the dose were analyzed. The contributions of the base current according to the defect types were also reported.It was declared that the radiation effect of neutrons was almost similar between the two transistor types, this effect at high dose may decrease the value of β to less than one. The Messenger-Spratt equation was used to describe the experimental results in this case. However, the experimental data demonstrated that the effect of gamma rays was generally higher on NPN than PNP transistors. This is mainly attributed to the difference in the behavior of the trapped positive charges in the SiO_2 layers. Meanwhile, this difference tends to be small for high gamma dose.
文摘Neurodegenerative diseases are a class of chronic and complex disorders featuring progressive loss of neurons in distinct brain areas.The mechanisms responsible for the disease progression in neurodegeneration are not fully illustrated.In this observational study,we have examined diverse biochemical parameters in the caudate and putamen of patients with Lewy body diseases(LBDs)and Alzheimer disease(AD),shedding some light on the involvement of oxidative damage and neuroinflammation in advanced neurodegeneration.We performed Spearman and Mantel-Cox analyses to investigate how oxidative stress and neuroinflammation exert comprehensive effects on disease progression and survival.Disease progression in LBDs correlated positively with poly(ADP-Ribose)and triggering receptors expressed on myeloid cell 2 levels in the striatum of LBD cohorts,indicating that potential parthanatos was a dominant feature of worsening disease progression and might contribute to switching microglial inflammatory phenotypes.Disease progression in AD corresponds negatively with 8-oxo-7,8-dihydro-2′-deoxyguanosine(8-oxo-d G)and myeloperoxidase concentrations in the striatum,suggesting that possible mitochondria dysfunction may be involved in the progression of AD via a mechanism ofβ-amyloid entering the mitochondria and subsequent free radicals generation.Patients with lower striatal 8-oxo-d G and myeloperoxidase levels had a survival advantage in AD.The age of onset also affected disease progression.Tissue requests for the postmortem biochemistry,genetics,and autoradiography studies were approved by the Washington University Alzheimer's Disease Research Center(ADRC)Biospecimens Committee(ethics approval reference number:T1705,approval date:August 6,2019).Recombinant DNA and Hazardous Research Materials were approved by the Washington University Environmental Health&Safety Biological Safety Committee(approval code:3739,approval date:February 25,2020).Radioactive Material Authorization was approved by the Washington University Environmental Health&Safety Radiation Safety Committee(approval code:1056,approval date:September 18,2019).
基金the research support of the College of Petroleum Engineering and Geosciences at King Fahd University of Petroleum&Minerals。
文摘The properties of oil and gas formation could be significantly damaged during drilling and completion operations as a result of mud invasion,fluid incompatibility and interaction with rock minerals.This paper presents a systematic method for evaluating formation damage during filter cake deposition(primary damage)and removal process(secondary damage).The role of primary damage in the evolution of secondary damage was also investigated.The interaction of the filter cake solvent(chelating agent solution)with the rock samples was implemented through core flooding experiment.Nuclear Magnetic Resonance(NMR)was used to evaluate the properties of the rock sample,pre and post filter cake deposition and removal processes.The results show that secondary damaged is a strong function of the location and the intensity of the primary damage.The rock type and its pore structure also play important roles in both primary and secondary damage.The extent of secondary damage depends on the amount of barium sulphate deposited during primary damage.The chelating agent used to dissolve the barites in sandstones,deposited the barite in the small pores while it enlarges the bigger pores.In contrast,the chelating agent in the carbonate samples had multiple barite deposition points.
基金the National Natural Science Foundation of China(Grant No.51809135)the National Natural Science Foundation of China-Shandong Joint Fund(Grant No.U1806227)the Natural Science Foundation of Shandong Province(Grant No.ZR2018BEE047).
文摘In connection with the design of floating wind turbines,stochastic dynamic analysis is a critical task considering nonlinear wind and wave forces.To study the random structural responses of a newly designed submerged tension leg platform(STLP)wind turbine,a set of dynamic simulations and comparison analysis with the MIT/NREL TLP wind turbine are carried out.The signal filter method is used to evaluate the mean and standard deviations of the structural response.Furthermore,the extreme responses are estimated by using the mean upcrossing rate method.The fatigue damages for blade root,tower,and mooring line are also studied according to the simulated time-series.The results and comparison analysis show that the STLP gives small surge and pitch motions and mooring line tensions in operational sea states due to the small water-plane area.Additionally,in severe sea states,the STLP gives lower extreme values of platform pitch,slightly larger surge and heave motions and better towerbase and mooring line fatigue performances than those of the MIT/NREL TLP.It is found that the STLP wind turbine has good performances in structural responses and could be a potential type for exploiting the wind resources located in deep waters.
