Investigation on small molecule-aptamer dissociation equilibria based on antisense displacement probe

Food safety is a major issue to public health and have attracted global attention.Fast,sensitive,and reliable detection methods for food hazardous substances is highly desirable.Aptamers which can bind to the target molecules with high affinity and specificity represent an attractive tool for the recognition of food hazardous substances,which play an important role in the development and application of new food safety detection technology.But current assays for characterizing small molecule-aptamer binding are limited by either the mass sensitivity or the size differentiation ability.Herein,we proposed a comprehensive method for assessing the dissociation equilibria of small molecule-aptamer,which is immobilized-free under ambient conditions.The design employs the Le Chatelier’s principle and could be used to effectively measure small molecule-aptamer interactions.ATP binding aptamer and anti-aflatoxin B1 aptamer were used as the model system to determine their affinity,in which their dissociation equilibria measurements are in excellent close to their previous work.Due to the simplicity and sensitivity of this new method,we believe that it could be recommended as an effective tool for characterizing small molecule-aptamer interactions and promote the further application of small molecular aptamer in food safety.

DISPLACEMENT WAVE OF THE BLOOD VESSEL——A MECHANICAL MODEL

According to clinical observations and model experiment,we have developed a theoretical mod- el and obtained its mathematical equations to investigate the displacement wave of the blood vessel.The waveform and its occurrence criterion have been obtained by using perturbation theory and numerical method. The present study suggests that the displacement wave is associated with the blood velocity waveform and the machanical behaviour of the blood vessel,but not with the pressure waveform.The clinical criterion is in agreement with the observations.

THE DISPLACEMENT WAVE THEORY OF BLOOD VESSEL

On the basis of the medical and mechanical analysis and explanations in this paper the visco-elastic simply supported beam model is proposed to treat the displacement wave of the blood vessels. The relationships between the displacement wave and blood vessel elasticity as well as the viscous dissipation of the blood and blood vessel are obtained. The corresponding relations of such kinds of pulses in the traditional Chinese medicine as smooth pulse, surface pulse and deep pulse to the displacement waves of blood vessels are also found. The computational results are in good agreement with those acquired in the experiments with ultrasonic wave.

“Parenchyma transection-first”strategy is superior to“tunnel-first”strategy in robotic spleen-preserving distal pancreatectomy with conservation of splenic vessels

Background: Creating a tunnel between the pancreas and splenic vessels followed by pancreatic parenchyma transection(“tunnel-first” strategy) has long been used in spleen-preserving distal pancreatectomy(SPDP) with splenic vessel preservation(Kimura’s procedure). However, the operation space is limited in the tunnel, leading to the risks of bleeding and difficulties in suturing. We adopted the pancreatic “parenchyma transection-first” strategy to optimize Kimura’s procedure. Methods: The clinical data of consecutive patients who underwent robotic SPDP with Kimura’s procedure between January 2017 and September 2022 at our center were retrieved. The cohort was classified into a “parenchyma transection-first” strategy(P-F) group and a “tunnel-first” strategy(T-F) group and analyzed. Results: A total of 91 patients were enrolled in this cohort, with 49 in the T-F group and 42 in the P-F group. Compared with the T-F group, the P-F group had significantly shorter operative time(146.1 ± 39.2 min vs. 174.9 ± 46.6 min, P < 0.01) and lower estimated blood loss [40.0(20.0–55.0) m L vs. 50.0(20.0–100.0) m L, P = 0.03]. Failure of splenic vessel preservation occurred in 10.2% patients in the TF group and 2.4% in the P-F group( P = 0.14). The grade 3/4 complications were similar between the two groups( P = 0.57). No differences in postoperative pancreatic fistula, abdominal infection or hemorrhage were observed between the two groups. Conclusions: The pancreatic “parenchyma transection-first” strategy is safe and feasible compared with traditional “tunnel-first strategy” in SPDP with Kimura’s procedure.

2022年1月8日门源M_(S)6.9地震同震位移场及其发震断层形变破裂特征

利用冷龙岭-托莱山断裂及其附近震前和震后GNSS观测资料,处理获取了2022年门源M_(S)6.9地震同震位移场,并以此为约束反演获取了地震同震破裂滑动分布图像,基于上述结果探讨了本次地震发震断层形变破裂特征,对比了区域震间与同震变形特征,结果表明:(1)此次地震在距震中约90 km范围内产生了10 mm及以上的同震永久变形,距震中160~200 km的GNSS连续站记录到的同震变形则十分微弱,总体在毫米级以下;(2)同震位移图像呈现典型的左旋走滑型同震变形模式.在距震中约3 km破裂带南侧的测站,其同震位移为近东向,大小445.9±3.3 mm,而在破裂带远场则呈现出典型的与左旋走滑型地震匹配的“四象限”对称分布的挤压或拉张尾端变形特征;(3)同震位移量以冷龙岭断裂-托莱山断裂为界,南北两盘具有明显的非对称性,南盘变形运动大于北盘;(4)托莱山断裂西段同震位移总体表现出随震中距减小而增大的“弹性回跳”现象,但其跨断层近场测站却并不服从上述同震变形特征,指示其并未参与此次地震破裂,考虑到托莱山断裂西段显著的左旋剪切应变能积累背景,其未来强震危险性值得关注.

The role of small vessel disease in development of Alzheimer's disease

Classically Alzheimer＇s disease and vascular dementia have been considered as two different entities, with their own clinical criteria, but relatively recent epidemiological and clinicopathological studies suggest an overlap between them sharing not only most of the risk factors and some clinical aspects but also pathophysiological mechanisms. Cerebrovascular lesions, especially small vessel disease （lacunar infarcts, white matter hyperintensities and microbleeds）, may magnify the effects of mild Alzheimer＇s disease pathology and promote the progression of cognitive decline and may also be a precursor of neuronal damage and dementia. ＂Vascular hypothesis＂ of Alzheimer＇s disease would open a window for new approaches and treatments.

Development of S11306+SA516Gr70 roll-bonded clad steel plate for pressure vessels

To meet the demand of the pressure vessel industry, Baosteel has developed an S11306 ＋ SA516Gr70 roll-bonded clad steel plate. Comprehensive inspections of the composition, microstructure, and properties are performed to systematically evaluate the steel plate in normalized state and normalized ＋ stress relieved state. The results show the cladding interface of the Sl1306 ＋ SA516Gr70 roll-bonded clad steel plate has high shear strength, and the base metal has good mechanical properties. The performance is fully consistent with the technical requirements of the roll-bonded clad steel plate for pressure vessels.

Indirect inguinal hernia containing portosystemic shunt vessel: A case report

BACKGROUND Inguinal hernia repair is one of the most common general surgical operations worldwide.We present a case of indirect inguinal hernia containing an expanded portosystemic shunt vessel.CASE SUMMARY We report a 72-year-old man who had a 4 cm×4 cm swelling in the right inguinal region,which disappeared with light manual pressure.Abdominal-pelvic computed tomography(CT)revealed a right inguinal hernia containing an expanded portosystemic shunt vessel,which had been noted for 7 years due to liver cirrhosis.We performed Lichtenstein’s herniorrhaphy and identified the hernia sac as being indirect and the shunt vessel existing in the extraperitoneal cavity through the internal inguinal ring.Then,we found two short branches between the expanded shunt vessel and testicular vein in the middle part of the inguinal canal and cut these branches to allow the shunt vessel to return to the extraperitoneal cavity of the abdomen.The hernia sac was returned as well.We encountered no intraoperative complications.After discharge,groin seroma requiring puncture at the outpatient clinic was observed.CONCLUSION If an inguinal hernia patient has portal hypertension,ultrasound should be used to determine the contents of the hernia.When atypical vessels are visualized,they may be shunt vessels and additional CT is recommended to ensure the selection of an adequate approach for safe hernia repair.

Microstructure and properties of S30403+Q345R roll-bonded clad steel plate for pressure vessels

To meet the demand of the domestic pressure vessel industry for roll-bonded clad steel plates, Baosteel has developed an S30403 ＋ Q345R roll-bonded clad steel plate. Comprehensive inspections of the composition, microstructure, and properties are made to systematically evaluate the steel plate in the normalized and normalized ＋ stress relieved states. The results show the cladding interface of the S30403 ＋ Q345R roll-bonded clad steel plate has high shear strength, the base metal has good properties, and the mechanical properties of the steel plate head and tail are uniform. The performance is fully consistent with the technical requirements of the roll-bonded clad steel plate for pressure vessels.

2022年3月17日皮山M_(S)5.2地震区域电磁异常综合分析

综合分析2022年3月17日皮山M_(S)5.2地震前震中附近存在的区域电磁异常特征。结果表明:①本次震中距离地磁低点位移预测线约280 km,且与优势发震时间接近,该异常对应本次地震;②本次地震虽然发生在地磁逐日比和地磁垂直强度极化预测区内,但震级偏小,且距离异常台站较远,异常不对应此次地震;③将地磁逐日比和低点位移进行综合分析有助于提高地震短期预测的准确性。

Free Vibration Analysis of FG-CNTRC Cylindrical Pressure Vessels Resting on Pasternak Foundation with Various Boundary Conditions

This study focuses on vibration analysis of cylindrical pressure vessels constructed by functionally graded carbon nanotube reinforced composites(FG-CNTRC).The vessel is under internal pressure and surrounded by a Pasternak foundation.This investigation was founded based on two-dimensional elastic analysis and used Hamilton’s principle to drive the governing equations.The deformations and effective-mechanical properties of the reinforced structure were elicited from the first-order shear theory(FSDT)and rule of mixture,respectively.The main goal of this study is to show the effects of various design parameters such as boundary conditions,reinforcement distribution,foundation parameters,and aspect ratio on the free vibration characteristics of the structure.

Uplift Resistance Calculation and Sensitive Analysis of Jack-up Wind Installation Vessels

The uplift resistance calculation is an important basis for the construction decisions of the jack-up wind installation vessel and the design of the jacking system,and determines the operation risk and reliability in the installation process of the wind turbine. The influence factors of the pile shoe's penetration depth and uplift resistance are analyzed,and the calculation model and flow of the uplift resistance are given. Based on a construction example,the influence rules are analyzed for the change of the pile shoe's structural parameters on the penetration depth and uplift resistance.The analysis results show that the penetration depth is more sensitive to the width of the pile shoe,and the height has greater influence on the uplift resistance than the length and width of the spud. With the increase of the height,the uplift resistance may increase rapidly.Although the decreases of the length,width and height of the pile shoe may reduce the uplift resistance,the penetration depth may increase in the meantime. This will increase the pulling pile time and reduce the construction efficiency. So the parameters of the pile shoe should be optimized according to the adaptable geology condition so as to obtain the optimal uplift resistance and working efficiency.

The Use of Anti-Platelet and/or Anticoagulant Agents in the Prevention of Large Vessel Vasculitis-Associated Ischemic Complications: A Meta-Analysis

Objective: To determine the effectiveness of antiplatelet and/or anticoagulant therapy (AP/AC) at reducing ischemic events in patients with Large Vessel Vasculitis (LVV). Methods: We performed a random effects meta-analysis of studies examining antiplatelet and/or anticoagulant therapy (AP/AC) and ischemic events in Takayasu’s Arteritis (TAK) or Giant Cell Arteritis (GCA). Severe ischemic events were defined as stroke, ischemic ocular manifestations and claudication symptoms. Any ischemic event included jaw claudication in addition to the above manifestations. Results: Seven studies met inclusion criteria: 1 TAK and 6 GCA. The majority of patients (>80%) were treated with ASA and treatment was initiated prior to diagnosis of LVV. Risk of severe and any ischemic event in patients with LVV treated with AP/AC versus no treatment was not significantly different (OR 0.570, 95% CI 0.243, 1.340 and OR 0.594, 95% CI 0.248, 1.421, respectively). For studies with follow-up data (26-76 months), AP/AC was protective for severe ischemic events (OR 0.18, 95% CI 0.04, 0.83). Findings were similar when excluding studies that did not account for potential confounders, such as cardiovascular risk factors. Conclusion: At follow-up, antiplatelet therapy significantly decreases ischemic events in patients with LVV. However, in most cases of GCA, the treatment was initiated prior to the diagnosis of vasculitis. The benefit of initiating anti-platelet therapy at the time of GCA diagnosis remains unclear.

Prevalence of Various Cancer-Related Risk Factors among the Forcibly Displaced Myanmar National Community, the Rohingya, in Bangladesh: A Preliminary Assessment

Background: Large numbers of Forcibly Displaced Myanmar Nationals (FDMN), also called the Rohingya community, in Bangladesh face chronic life-threatening illnesses. Symptoms concerning for a cancer diagnosis are not easily evaluated and treated by healthcare systems available to this population. We conducted a rapid needs assessment of cancer screening and pain and palliative care with the goal of identifying the prevalence of cancer risk factors among the Rohingya who attended local health facilities. Methods: A cross-sectional study was conducted in the Kutupalong camp of Ukhiya, Cox’s Bazar among the Rohingya community. Data were?collected through purposive sampling. Face-to-face interviews were done using a structured questionnaire. Statistics were analyzed by using IBM SPSS 23.?Results: Out of 85 participants, 75 were female and 10 were male. 70 (82.4%) were uneducated (defined as lacking any formal institutional education), 10 (11.8%) people completed the primary level education and only 5 (5.9%) people received secondary level education. There were many participants with pulmonary disease with 35 (41.2%) people endorsing a history of asthma, bronchitis, and/or tuberculosis. There was a lack of female menstrual sanitation and hygiene with only 25 (29.4%) patients using sanitary napkins, that were donated by Non Government Organizations. Only 5.9% of the women had received any form of cervical cancer screening.?Conclusion: This study identifies risk factors associated with cancers and life-limiting diseases among the FDMN Rohingya refugees in Bangladesh. It is necessary to develop targeted education, cancer screening and cancer awareness programs for this population.

Retinal thickness and vascular parameters using optical coherence tomography in Alzheimer's disease:a meta-analysis

Examining the retinal tissue has the potential to provide a unique method and technique to quantify Alzheimer’s disease-related changes in participants at various stages of the disease.In this metaanalysis,we aimed to investigate the association of various optical coherence tomography parameters with Alzheimer’s disease and whether retinal measurements can be used to diffe rentiate between Alzheimer’s disease and control subjects.Scientific databases including Google Schola r,Web of Science,and PubMed were systematically searched for published articles that evaluated retinal nerve fiber layer thickness and retinal microvascular network in Alzheimer’s disease and control subjects.Seventy-three studies(5850 participants,including 2249 Alzheimer’s disease patients and 3601controls) were included in this meta-analysis.Relative to controls,Alzheimer’s disease patients had a significantly lower global retinal nerve fiber layer thickness(standardized mean difference [SMD]=-0.79,95% confidence intervals [CI]:-1.03 to-0.54,P <0.00001) as well as each quadrant being thinner in Alzheimer’s disease versus controls.Regarding macular paramete rs,values measured by optical coherence tomography were significantly lower in Alzheimer’s disease than controls for macular thickness(pooled SMD:-0.44,95% CI:-0.67 to-0.20,P=0.0003),foveal thickness(pooled SMD=-0.39,95% CI:-0.58 to-0.19,P <0.0001),ganglion cell inner plexiform layer(SMD=-1.26,95% CI:-2.24 to-0.27,P=0.01) and macular volume(pooled SMD=-0.41,95% CI-0.76 to-0.07,P=0.02).Analysis using optical coherence tomography angiography parameters revealed mixed results between Alzheimer’s disease and controls.Superficial vessel density(pooled SMD=-0.42,95% CI:-0.68 to-0.17,P=0.0001) and deep vessel density(pooled SMD=-0.46,95% CI:-0.75 to-0.18,P=0.001) were found to be thinner in Alzheimer’s disease patients whereas the foveal avascular zone(SMD=0.84,95% CI:0.17-1.51,P=0.01) was larger in controls.Vascular density and thickness of various retinal laye rs were decreased in Alzheimer’s disease patients compared to controls.Our results provide evidence for optical coherence tomography technology having the potential to detect retinal and microvascular changes in patients diagnosed with Alzheimer’s disease and aid in monito ring and early diagnosis methods.

血液在S型血管中流动的数值模拟

运用SIMPLE(semi-implicit Method for Pressure Linked Equations)算法数值模拟了2D(2 Dimensional)和3D(3 Dimensional)情况下S型血管内血液的流动,探讨了不同入口速度下血管内血液流动速度、压强等的分布;比较了2D和3D情况下流场分布的异同。不同的入口速度对血管内血液的流场、压强分布有很大影响,入口速度较大时,血管内血液流动速度更大、压降更大;在速度相同的情况下,3D血管内的速度和压强要大于2D血管内的速度和压强,流场分布也存在较大不同。本结论有望为分析常见的血管类疾病及研究血管中血液的流动机理提供数据支撑。

2023年12月18日甘肃积石山6.2级地震震源机制及其对周围区域的应力影响

为研究2023年甘肃积石山6.2级地震对周围地区的应力影响,本文首先根据各个机构和学者提供的震源机制数据确定了本次地震的震源机制中心解。节面Ⅰ:走向159.08°,倾角40.57°,滑动角112.46°;节面Ⅱ:走向310.52°,倾角53.05°,滑动角71.88°。此次地震为逆冲型地震。将当地的应力体系投影到震源机制中心解的两个节面上,得到相对剪应力分别为0.797和0.951,可以看出该地震是区域构造应力场作用下的一次正常能量释放。拉脊山北缘断裂呈NNW走向,SWW倾向,倾角为45°~55°,与震源机制中心解的节面Ⅰ较为一致,判断拉脊山北缘断裂为此次地震发震断裂。基于该地震破裂模型及均匀弹性半空间模型,计算此次地震对周边地区产生的同震位移场及应变场。体应变在震中呈现拉张,距离震中较远的东北和西南两侧呈现轻微拉张,震中周边呈现压缩,东侧压缩表现更为突出。水平位移场表现为在震中西北侧和小部分东南侧的物质向外涌出,而东北侧和西南侧的物质涌入震中;与水平位移场相对应,垂直位移场在震中表现为隆升,而四周表现为略微沉降。

2021年5月21日M_(S)6.4漾濞地震GNSS同震变形场及其约束反演的破裂滑动分布

2021年5月21日云南大理州漾濞县发生了M_(S)6.4强震.地震未产生明显的地表破裂,但前震-主震-余震大致呈线状展布于维西—乔后—巍山断裂的西南侧.我们基于覆盖震中区域的高密度连续GNSS观测台阵,观测获得了震区周围50 km范围的高精度、高密度三维同震形变场.结果显示:地震破裂为明显的右旋走滑兼拉张;地表形变场呈现出走滑断裂前端压缩隆升、尾端拉张下沉的典型变形模式;GNSS观测到最大水平位移和垂直下沉分别达46 mm(漾濞县淮安村周围)和-44 mm(漾濞县秀岭林场周围);发震断裂的地表错动从漾濞淮安村GNSS观测站和秀岭林场GNSS观测站之间的狭小地带穿过.在此基础上,我们以前震和主震精定位结果为约束,推测发震断层面走向135°、倾向SW、倾角80°,进而通过弹性半空间断裂位错模型,对发震断层面的同震滑动分布进行了反演.初步反演结果表明:同震滑动主要集中分布在3~12 km深度范围内,矩震级为M_(W)6.04,滑动量分布与前震序列呈现较好的空间一致性.

R/S分析在滑坡变形趋势预测中的应用

R/S分析(重标度极差分析)是一种描述和刻画非线性时间序列的有效方法。针对滑坡地表位移监测时序确定性与随机性共存的复杂非线性特征,对三峡库区的一个实例滑坡的长时期位移时序进行了R/S分析。分别计算了滑坡累积位移时序和增量位移时序的Hurst指数,指出增量位移时序是更有效的分形结构,其Hurst指数能定量刻画滑坡的变形趋势;分析了滑坡增量位移时序的非周期循环长度,发现滑坡前缘与中后部的增量位移时序Hurst指数和非周期循环长度存在显著差别,并从滑坡变形诱发机制上解释了这一差异产生的内在原因;最后基于滑坡变形演化的力学机理,提出了一个利用增量位移时序Hurst指数判断滑坡加速变形阶段的概念模型:为提高和完善滑坡失稳时间预测预报理论,提供了一个有意义的新思路和新方法。

利用高频GPS进行地表同震位移监测及震相识别

结合日本3.11大地震,利用近震区和远震区若干测站的高频GPS观测数据,采用动态精密单点定位技术分析了强震时复杂的地表运动时序,获得了地表同震位移.在此基础上提出利用S变换对高频GPS地震波进行震相识别,有效拾取了P波初至,反演了P波传播速度并与地震仪数据、USGS提供的参考值进行了对比和分析,为后续地震应急、地震预警提供了重要的、科学的决策依据.