Role of proning and positive end-expiratory pressure in COVID-19

The novel coronavirus,which was declared a pandemic by the World Health Organization in early 2020 has brought with itself major morbidity and mortality.It has increased hospital occupancy,heralded economic turmoil,and the rapid transmission and community spread have added to the burden of the virus.Most of the patients are admitted to the intensive care unit(ICU)for acute hypoxic respiratory failure often secondary to acute respiratory distress syndrome(ARDS).Based on the limited data available,there have been different opinions about the respiratory mechanics of the ARDS caused by coronavirus disease 2019(COVID-19).Our article provides an insight into COVID-19 pathophysiology and how it differs from typical ARDS.Based on these differences,our article explains the different approach to ventilation in COVID-19 ARDS compared to typical ARDS.We critically analyze the role of positive end-expiratory pressure(PEEP)and proning in the ICU patients.Through the limited data and clinical experience are available,we believe that early proning in COVID-19 patients improves oxygenation and optimal PEEP should be titrated based on individual lung compliance.

Quantifying the impact of earthquakes and geological factors on spatial heterogeneity of debris-flow prone areas:A case study in the Hengduan Mountains

Understanding the spatial heterogeneity of debris-flow-prone areas holds significant implications for regional risk management, particularly in seismically active regions with geological faults. Despite the significance of this knowledge, a comprehensive quantification of the influence of regional topographical and geological factors on the spatial heterogeneity of debris-flow-prone areas has been lacking. This study selected the Hengduan Mountains, an earthquake-prone region characterized by diverse surface conditions and complex landforms, as a representative study area. An improved units zoning and objective factors identification methodology was employed in earthquake and fault analysis to assess the impact of seismic activity and geological factors on spatial heterogeneity of debrisflow prone areas. Results showed that the application of GIS technology with hydrodynamic intensity and geographical units analysis can effectively analyze debris-flow prone areas. Meanwhile, earthquake and fault zones obviously increase the density of debrisflow prone catchments and make them unevenly distributed. The number of debris-flow prone areas shows a nonlinear variation with the gradual increase of geomorphic factor value. Specifically, the area with 1000 m-2500 m elevation difference, 25°-30° average slope, and 0.13-0.15 land use index is the most favorable conditions for debris-flow occurrence;The average annual rainfall from 600 to 1150 mm and landslides gradient from 16° to 35° are the main causal factors to trigger debris flow. Our study sheds light on the quantification of spatial heterogeneity in debris flow-prone areas in earthquake-prone regions, which can offer crucial support for post-debris flow risk management strategies.

A review of rockburst:Insights from engineering sites to theoretical investigations

Rockburst has perennially posed a formidable challenge to the stability of underground engineering works,particularly under conditions of deep-seated high stress.This paper provides a comprehensive review of recent advancements in on-site research related to rockburst occurrences,covering on-site case analyses,monitoring methodologies,early warning systems,and risk(proneness)evaluation.Initially,the concepts and classifications of rockburst based on on-site understanding were summarized.The influences of structural planes(in various spatial distribution combinations),in-situ stress(particularly magnitude and direction of the principal stress),dynamic disturbances,and excavation profiles on rockburst were thoroughly assessed and discussed through the analysis of published rockburst cases and on-site survey results.Subsequently,a compendium of commonly employed on-site monitoring techniques was outlined,delineating their respective technical attributes.Particular emphasis is accorded to the efficacy of microseismic monitoring technology and its prospective utility in facilitating dynamic rockburst early warning mechanisms.Building upon this foundation,the feasibility of assessing rockburst propensity while considering on-site variables is verified,encompassing the selection and quantitative evaluation of pertinent indicators.Ultimately,a comprehensive synthesis of the paper is presented,alongside the articulation of prospective research goals for the future.

Rockburst proneness considering energy characteristics and sample shape effects

Accurate prediction of rockburst proneness is one of challenges for assessing the rockburst risk and selecting effective control measures.This study aims to assess rockburst proneness by considering the energy characteristics and qualitative information during rock failure.Several representative rock types in cylindrical and cuboidal sample shapes were tested under uniaxial compression conditions and the failure progress was detected by a high-speed camera.The far-field ejection mass ratio(FEMR)was determined considering the qualitative failure information of the rock samples.The peak-strength energy impact index and the residual elastic energy index were used to quantitatively evaluate the rockburst proneness of both cylindrical and cuboidal samples.Further,the performance of these two indices was analyzed by comparing their estimates with the FEMR.The results show that the accuracy of the residual elastic energy index is significantly higher than that of the peak-strength energy impact index.The residual elastic energy index and the FEMR are in good agreement for both cylindrical and cuboidal rock materials.This is because these two indices can essentially reflect the common energy release mechanism characterized by the mass,ejection velocity,and ejection distance of rock fragments.It suggests that both the FEMR and the residual elastic energy index can be used to accurately measure the rockburst proneness of cylindrical and cuboidal samples based on uniaxial compression test.

Percutaneous antegrade management of large proximal ureteral stones using non-papillary puncture

Objective:To evaluate the feasibility and the safety of medial non-papillary percutaneous nephrolithotomy(npPCNL)for the management of large proximal ureteral stones.Methods:We evaluated prospectively collected data of 37 patients with large proximal ureteral stones more than 1.5 cm in diameter treated by prone npPCNL.Depending on stone size,in-toto stone removal or lithotripsy using the Lithoclast®Trilogy(EMS Medical,Nyon,Switzerland)was performed.Perioperative parameters including operative time(from start of puncture to the skin suturing),stone extraction time(from the first insertion of the nephroscope to the extraction of all stone fragments),and the stone-free rate were evaluated.Results:Twenty-one males and 16 females underwent npPCNL for the management of large upper ureteral calculi.The median age and stone size of treated patients were 58(interquartile range[IQR]:51-69)years and 19.3(IQR:18.0-22.0)mm,respectively.The median operative time and stone extraction time were 25(IQR:21-29)min and 8(IQR:7-10)min,respectively.One case(2.7%)of postoperative bleeding and two cases(5.4%)of prolonged fever were managed conservatively.The stone-free rate at a 1-month follow-up was 94.6%.Conclusion:The npPCNL provides a straight route to the ureteropelvic junction and proximal ureter.Approaching from a dilated portion of the ureter under low irrigation pressure with larger diameter instruments results in effective and safe stone extraction within a few minutes.

Effect of Prone Position in Severe Covid-19 Patients in a Referral Center: A Cohort Retrospective Study

Introduction: Covid-19 is defined as a pandemic disease by WHO, in November 2023, WHO recorded 772.1 million confirmed cases and 6.9 million deaths, including 68,382 confirmed cases and 1426 deaths in Madagascar. The management of severe cases of Covid-19 remains a challenge for the healthcare system in a resource-limited country, due to the consumption of human resources, the shortage of medical resources and the lack of capacity in resource-limited countries. Prone position (PP) improves survival in acute respiratory distress, and numerous studies have shown that during Covid-19, it reduces mortality rates at 28 and 90 days, and increases the number of days without mechanical ventilation. However, data on the beneficial effects of PP remain limited in low-income countries. In this context, our study aims to evaluate the benefits of the prone position for severe Covid-19 patients in a referral center in Madagascar. Method: This is a retrospective cohort study, during the 2nd and 3rd waves of COVID-19, over a period of 11 months in two wards managing COVID-19 cases. We included all patients aged 15 and over with severe forms of COVID-19 who required 6 l/min of oxygen therapy. Results: We enrolled 123 patients, including 40 in the prone position and 83 in the supine position, with a mean age of 60.5 ± 12 years. The prone position (DV) reduced the risk of probable complications of COVID-19 with a strong association in terms of use of respiratory assistance (OR = 0.15;95% CI = 0.05 - 0.47), respiratory deterioration (OR = 0.22;95% CI = 0.09 - 0.58), shock (OR = 0.30;95% CI = 0.11 - 0.79) and hemodynamic instability (OR = 0.33;95% CI = 0.12 - 0.95). Univariate analysis of the effect of prone position on SpO2 showed improvement with significant associations with SpO2 at Day 1- Day 3, D4 - D7, D8 - D14, and persisting even at D15 - D21, D3 and D2 before discharge, and at discharge. In the overall population, the mean length of hospital stay was 22.8 ± 22.1 days, with extremes of 1 and 67 days. Univariate analysis of the effect of the prone position showed a reduction in length of hospital stay with a strong association (p = 0.001) and a mean difference of 14 days. The prone position reduced mortality with a significant association (OR = 0.44;95% CI = 0.20 - 0.98). Conclusion: Awake prone position prevents complications of COVID, improves SPO2 even up to hospital discharge and reduces hospital stay. This practice is simple, less costly and suitable in low income countries.

Statistical Analysis of Accident Proneness of Drivers

A mathematical model describing the risks of road accidents has been built on the basis of statistical data of drivers’ accident rate. It has been revealed that drivers can be divided by the degree of their accident proneness into four categories with sharply differing probabilities of road accidents. It has been shown that there is a possibility of classification of drivers in accordance with specified categories.

Advances in the Use of Prone Cardiopulmonary Resuscitation During Spinal Surgery in the Prone Position

Spinal surgery is usually performed in the prone position, which is a longer and more difficult procedure and is prone to complications such as circulatory dysfunction and stress injuries. Among them, stress injury is the main complication of prone spine surgery, but the reasons for stress injury in prone spine surgery are not clear, and whether prone cardiopulmonary resuscitation (CPR) can be used needs to be further verified. Supine cardiopulmonary resuscitation is commonly used in posterior spinal surgery, retroperitoneal surgery, and so on, which can effectively improve the patient’s hypoxemia. Such surgeries require a high level of anesthetic management, and cardiopulmonary resuscitation is necessary if a patient in a prone position experiences cardiac arrest. In the process of cardiopulmonary resuscitation, supine cardiopulmonary resuscitation is often used, especially for some obese patients, if they are immediately changed to the supine position, it takes up more time, there may be wound infection, and there is a possibility of missing the optimal rescue and resuscitation time. Based on this, this paper reviews the use of prone-position cardiopulmonary resuscitation for spinal surgery in the prone position.

Effect of Prone Position Ventilation in Patients with Severe Craniocerebral Injury Complicated with Pulmonary Infection

Objective:To investigate the effects of prone ventilation in patients with severe traumatic brain injury combined with pulmonary infection.Methods:A total of 100 patients with severe traumatic brain injury combined with pulmonary infection in the hospital were randomly divided into a prone ventilation group and a conventional ventilation group,with 50 patients in each group.The Glasgow Coma Scale(GCS)score,APACHE II score,sputum culture results,oxygenation indicators,and prognosis were compared between the two groups.Data were processed using SPSS 25.0 statistical software,and t-tests and chi-square tests were used to compare continuous and categorical variables,respectively.Results:The experimental group showed better oxygenation indicators,a lower positive rate of sputum cultures,and reduced intracranial pressure compared to the control group(all P<0.05).Multivariate Cox regression analysis indicated that GCS score,APACHE II score,and prone ventilation were independent risk factors affecting patient prognosis(all P<0.05).Conclusion:Prone ventilation can improve oxygenation,reduce the risk of pulmonary infection,and decrease intracranial pressure in patients with severe traumatic brain injury combined with pulmonary infection,thereby improving patient prognosis.GCS score and APACHE II score can serve as important indicators for prognostic evaluation.

Clinical Nursing for Patients Undergoing Prone-Position Laparoscopic Partial Nephrectomy

Objective:To explore effective nursing strategies for patients undergoing prone-position laparoscopic partial nephrectomy.Methods:A total of 19 patients undergoing prone-position laparoscopic partial nephrectomy were selected,with hospital admission spanning from January 2024 to June 2024.Patients were randomly divided into the study group(n=10)and the control group(n=9).The control group received basic nursing care,while the study group received comprehensive high-quality nursing care.The recovery period,length of hospital stay,complication rates,SCL-90 scores,and nursing quality scores were compared between the two groups.Results:The recovery period and hospital stay were significantly shorter in the study group compared to the control group(P<0.05).The complication rate in the study group was lower than that in the control group(P<0.05).After the nursing intervention,the SCL-90 scores of the study group were lower than those of the control group(P<0.05).Nursing quality scores were higher in the study group than in the control group(P<0.05).Conclusion:Comprehensive high-quality nursing intervention for patients undergoing prone-position laparoscopic partial nephrectomy can shorten the recovery period and hospital stay,reduce the complication rate,improve mental health,and enhance nursing quality,making it suitable for wider application in medical institutions.

Error-prone PCR致哈茨木霉几丁质酶突变的条件优化

运用Error-prone PCR对哈茨木霉几丁质酶基因(Chit42)进行人工突变。在常规PCR基础上,通过提高体系中Mg2+浓度,适当加入一定浓度Mn2+,调节四种dNTP(dATP、dGTP、dCTP、dGTP)浓度,得到产生明显突变效果的试验条件。在Error-prone PCR中,使用5.0 mmol·L-1Mg2+,0.5 mmol·L-1Mn2+,0.04 mmol·L-1dATP和dGTP,1.5 mmol·L-1dTTP和dCTP进行扩增后,随机挑选10个克隆测序,累积13 370个碱基,检测到57个突变,平均突变率为0.4%。为产生优良突变株、酶分子定向进化奠定基础。

黄连解毒汤对自发性糖尿病大鼠免疫炎症因子及损伤的影响

目的:观察黄连解毒汤对自发性糖尿病大鼠心肌免疫炎症因子的影响及对心肌损伤的防治作用。方法:GK大鼠30只随机分为GK对照组、二甲双胍组、黄连解毒汤组,正常大鼠10只作为正常对照组分别灌胃12周,测定心肌匀浆核因子-κB(NF-κB)、细胞间黏附分子-1(sICAM-1)、白介素-1(IL-1)、肿瘤坏死因子(TNF-α)、内皮素-1(ET-1)含量。取心肌切片作HE染色。结果:2药物组血糖均下降(P<0.01)。GK对照组各炎症因子升高(P<0.01～0.05),黄连解毒汤组降低(P<0.01～0.05),其中NF-κB、TNF-α、ET-1与二甲双胍比较下降程度较大(P<0.01～0.05)。HE染色显示黄连解毒汤组心肌损伤明显减轻。结论:黄连解毒汤可防治糖尿病心肌炎症损伤。

俯卧位通气对急性呼吸窘迫综合征患者预后影响的荟萃分析

目的：系统评价俯卧位通气（PPV）对急性呼吸窘迫综合征（ARDS）患者预后的影响。方法检索美国国家医学图书馆PubMed数据库、WebofScience、Cochrane系统评价和临床试验数据库、生物医学与药理学文摘数据库（EMBASE）、中国生物医学文献数据库（CBM）和中国期刊网全文数据库（CNKI）等数据库，系统收集相关随机对照临床试验（RCT）文献。按Cochrane系统评价方法筛选试验、评价质量、提取资料，采用RevMan5．1软件进行Meta分析。结果最终纳入10项临床对照试验，共2187例患者，全部为随机对照试验，研究质量为B或C。荟萃分析结果显示，与对照组比较，PPV可明显提高ARDS患者氧合指数（6h氧合指数比较：MD＝28．19，95％CI为12．39～43．98，P＝0．0005；4d氧合指数比较：MD＝22．34，95％CI为10．77～33．91，P＝0.0002；10d氧合指数比较：MD＝18．07，95％CI为3．50～32．64，P＝0．02）。与对照组比较，PPV能够降低总体死亡率（OR＝0．75，95％CI为0．59～0．96，P＝0．02），但ICU死亡率（OR＝0．74，95％CI为0．51～1．05，P＝0．09）、28d死亡率（OR＝0．75，95％CI为0．44～1．29，P＝0．30）、90d死亡率（OR＝0．69，95％CI为0．30～1．60，P＝0．39）及6个月死亡率（OR＝0．88，95％CI为0．62～1.26，P＝0．49）两组比较差异均无统计学意义。PPV组住ICU天数与对照组比较差异有统计学意义（MD＝1．43，95％CI为0．38～2．48，P＝0．007），而机械通气天数（受访90d）两组比较差异无统计学意义（MD＝-0．42，95％CI为-1．56～0．72，P＝0．47）。PPV组呼吸机相关肺炎发生率与对照组比较差异无统计学意义（OR＝0．83，95％CI为0．62～1．13，P＝0．24），压疮发生率PPV组高于对照组（OR＝1．36，95％CI为1．06～1．74，P＝0．01），意外拔管发生率两组比较差异无统计学意义（OR＝0．94，95％CI为0．62～1．42，P＝0．75），气胸发生率两组比较差异无统计学意义（OR＝0．75，95％CI为0．45～1．25，P＝0．27）。结论应用PPV治疗ARDS患者能明显提高氧合指数，降低总死亡率，尤其对于重度ARDS患者，可明显改善预后。

Rockburst proneness criteria for rock materials:Review and new insights

To review the rockburst proneness(or tendency)criteria of rock materials and compare the judgment accuracy of them,twenty criteria were summarized,and their judgment accuracy was evaluated and compared based on the laboratory tests on fourteen types of rocks.This study begins firstly by introducing the twenty rockburst proneness criteria,and their origins,definitions,calculation methods and grading standards were summarized in detail.Subsequently,to evaluate and compare the judgment accuracy of the twenty criteria,a series of laboratory tests were carried out on fourteen types of rocks,and the rockburst proneness judgment results of the twenty criteria for the fourteen types of rocks were obtained accordingly.Moreover,to provide a unified basis for the judgment accuracy evaluation of above criteria,a classification standard(obtained according to the actual failure results and phenomena of rock specimen)of rockburst proneness in laboratory tests was introduced.The judgment results of the twenty criteria were compared with the judgment results of this classification standard.The results show that the judgment results of the criterion based on residual elastic energy(REE)index are completely consistent with the actual rockburst proneness,and the other criteria have some inconsistent situations more or less.Moreover,the REE index is based on the linear energy storage law and defined in form of a difference value and considered the whole failure process,and these superior characteristics ensure its accuracy.It is believed that the criterion based on REE index is comparatively more accurate and scientific than other criteria,and it can be recommended to be applied to judge the rockburst proneness of rock materials.

Laparoscopic liver resection for posterosuperior tumors using caudal approach and postural changes: A new technical approach

Laparoscopic liver resection(LLR) for tumors in the posterosuperior liver [segment(S) 7 and deep S6] is a challenging clinical procedure. This area is located in the bottom of the small subphrenic space(rib cage), with the large and heavy right liver on it when the patient is in the supine position. Thus, LLR of this area is technically demanding because of the handling of the right liver which is necessary to obtain a fine surgical view, secure hemostasis and conduct the resection so as to achieve an appropriate surgical margin in the cage. Handling of the right liver may be performed by the hand-assisted approach, robotic liver resection or by using spacers, such as a sterile glove pouch. In addition, the operative field of posterosuperior resection is in the deep bottom area of the subphrenic cage, with the liver S6 obstructing the laparoscopic caudal view of lesions. The use of intercostal ports facilitates the direct lateral approach into the cage and to the target area, with the combination of mobilization of the liver. Postural changes during the LLR procedure have also been reported to facilitate the LLR for this area, such as left lateral positioning for posterior sectionectomy and semi-prone positioning for tumors in the posterosuperior segments. In our hospital, LLR procedures for posterosuperior tumors are performed via the caudal approach with postural changes. The left lateral position is used for posterior sectionectomy and the semi-prone position is used for S7 segmentectomy and partial resections of S7 and deep S6 without combined intercostal ports insertion. Although the movement of instruments is restricted in the caudal approach, compared to the lateral approach, port placement in the para-vertebra area makes the manipulation feasible and stable, with minimum damage to the environment around the liver.

Bench-to-bedside strategies for osteoporotic fracture: from osteoimmunology to mechanosensation

Osteoporosis is characterized by a decrease in bone mass and strength, rendering people prone to osteoporotic fractures caused by low-energy forces. The primary treatment strategy for osteoporotic fractures is surgery;however, the compromised and comminuted bones in osteoporotic fracture sites are not conducive to optimum reduction and rigid fixation. In addition, these patients always exhibit accompanying aging-related disorders, including high inflammatory status, decreased mechanical loading and abnormal skeletal metabolism, which are disadvantages for fracture healing around sites that have undergone orthopedic procedures. Since the incidence of osteoporosis is expected to increase worldwide, orthopedic surgeons should pay more attention to comprehensive strategies for improving the poor prognosis of osteoporotic fractures. Herein, we highlight the molecular basis of osteoimmunology and bone mechanosensation in different healing phases of elderly osteoporotic fractures, guiding perioperative management to alleviate the unfavorable effects of insufficient mechanical loading, high inflammatory levels and pathogen infection. The well-informed pharmacologic and surgical intervention, including treatment with anti-inflammatory drugs and sufficient application of antibiotics, as well as bench-to-bedside strategies for bone augmentation and hardware selection, should be made according to a comprehensive understanding of bone biomechanical properties in addition to the remodeling status of osteoporotic bones, which is necessary for creating proper biological and mechanical environments for bone union and remodeling. Multidisciplinary collaboration will facilitate the improvement of overall osteoporotic care and reduction of secondary fracture incidence.

Rock brittleness indices and their applications to different fields of rock engineering:A review

Brittleness is an important parameter controlling the mechanical behavior and failure characteristics of rocks under loading and unloading conditions,such as fracability,cutability,drillability and rockburst proneness.As such,it is of high practical value to correctly evaluate rock brittleness.However,the definition and measurement method of rock brittleness have been very diverse and not yet been standardized.In this paper,the definitions of rock brittleness are firstly reviewed,and several representative definitions of rock brittleness are identified and briefly discussed.The development and role of rock brittleness in different fields of rock engineering are also studied.Eighty brittleness indices publicly available in rock mechanics literature are compiled,and the measurement method,applicability and limitations of some indices are discussed.The results show that(1)the large number of brittleness indices and brittleness definitions is attributed to the different foci on the rock behavior when it breaks;(2)indices developed in one field usually are not directly applicable to other fields;and(3)the term“brittleness”is sometimes misused,and many empirically-obtained brittleness indices,which lack theoretical basis,fail to truly reflect rock brittleness.On the basis of this review,three measurement methods are identified,i.e.(1)elastic deformation before fracture,(2)shape of post-peak stressestrain curves,and(3)methods based on fracture mechanics theory,which have the potential to be further refined and unified to become the standard measurement methods of rock brittleness.It is highly beneficial for the rock mechanics community to develop a robust definition of rock brittleness.This study will undoubtedly provide a comprehensive timely reference for selecting an appropriate brittleness index for their applications,and will also pave the way for the development of a standard definition and measurement method of rock brittleness in the long term.

Mechanical properties and rockburst proneness of phyllite under uniaxial compression

To investigate the influence of the bedding angle,β,on the mechanical properties and rockburst proneness,uniaxial compression tests were conducted using cylindrical phyllite specimens with different bedding angles.According to the results,the peak stress,peak strain,cumulative acoustic emission counts,and potential energy of the elastic strain exhibited a U-shaped change trend.With an increase in β from 0°to 90°,the failure mode transformed from tensile splitting failure along the bedding plane to shear slip failure along the weak bedding plane.Finally,the failure mode evolved into a tensile splitting failure across the bedding plane.When β=15°,30°,and 45°,the phyllite specimens exhibited strong,slight,and moderate rockburst proneness,with strong,slight,and moderate shear slip rockbursts,respectively.When β=0°,60°,75°,and 90°,the phyllite specimens had extremely strong rockburst proneness,and an extremely strong strain rockburst occurred.

Acupuncture improves dendritic structure and spatial learning and memory ability of Alzheimer's disease mice

Acupuncture can improve the cognitive state of Alzheimer＇s disease, but its mechanism is not clear. Dendritic atrophy and synaptic loss in Alzheimer＇s disease brain are positively correlated with cognitive damage. Therefore, we speculated that the effect of acupuncture on improving cognitive function may be associated with reduced dendritic damage in the brain. Acupuncture at Qihai（CV6）, Zhongwan（CV12）, Danzhong（CV17）, bilateral Zusanli（ST36）, and bilateral Xuehai（SP10） acupoints was performed once a day（1-day rest after 6-day treatment） for 14 consecutive days. Senescence-accelerated mouse prone 8（SAMP8） mice without acupuncture and senescence-accelerated mouse resistant 1（SAMR1） mice were used as normal controls. After 14 days of treatment, spatial learning and memory ability of mice was assessed in each group using the Morris water maze. Dendritic changes of pyramidal cells in the hippocampal CA1 region were analyzed by quantitative Golgi staining. Our results showed that acupuncture shortened escape latency and lengthened retention time of the former platform quadrant in SAMP8 mice. Further, SAMP8 mice exhibited a significant increase in the number of apical and basal dendritic branches and total length of apical and basal dendrites after acupuncture. These results suggest that acupuncture improves spatial learning and memory ability of middle-aged SAMP8 mice by ameliorating dendritic structure.Acupuncture can improve the cognitive state of Alzheimer＇s disease, but its mechanism is not clear. Dendritic atrophy and synaptic loss in Alzheimer＇s disease brain are positively correlated with cognitive damage. Therefore, we speculated that the effect of acupuncture on im- proving cognitive function may be associated with reduced dendritic damage in the brain. Acupuncture at Qihai （CV6）, Zhongwan （CV 12）, Danzhong （CV17）, bilateral Zusanli （ST36）, and bilateral Xuehai （SP10） acupoints was performed once a day （1-day rest after 6-day treat- ment） for 14 consecutive days. Senescence-accelerated mouse prone 8 （SAMP8） mice without acupuncture and senescence-accelerated mouse resistant 1 （SAMR1） mice were used as normal controls. After 14 days of treatment, spatial learning and memory ability of mice was assessed in each group using the Morris water maze. Dendritic changes of pyramidal cells in the hippocampal CA1 region were analyzed by quantitative Golgi staining. Our results showed that acupuncture shortened escape latency and lengthened retention time of the former platform quadrant in SAMP8 mice. Further, SAMP8 mice exhibited a significant increase in the number of apical and basal dendritic branches and total length of apical and basal dendrites after acupuncture. These results suggest that acupuncture improves spatial learning and memory ability of middle-aged SAMP8 mice by ameliorating dendritic structure.

Rock burst proneness prediction by acoustic emission test during rock deformation

Rock burst is a severe disaster in mining and underground engineering,and it is important to predict the rock burst risk for minimizing the loss during the constructing process.The rock burst proneness was connected with the acoustic emission(AE) parameter in this work,which contributes to predicting the rock burst risk using AE technique.Primarily,a rock burst proneness index is proposed,and it just depends on the heterogeneous degree of rock material.Then,the quantificational formula between the value of rock burst proneness index and the accumulative AE counts in rock sample under uniaxial compression with axial strain increases is developed.Finally,three kinds of rock samples,i.e.,granite,limestone and sandstone are tested about variation of the accumulative AE counts under uniaxial compression,and the test data are fitted well with the theoretic formula.