Design and Research of Active Gravity Unloading Device for Large Aperture Optical Mirror

The large aperture optical mirror for space is processed and tested in the gravity environment on the ground. After entering space, gravity disappears due to the change of environment, and the mirror surface that has met the engineering requirements on the ground will change, seriously affecting the imaging quality. In order to eliminate the influence of gravity and to ensure the consistency of space and ground, gravity unloading must be performed. In order to meet the requirements of processing and testing for the large aperture space mirror in the state of vertical optical axis, a universal gravity unloading device was proposed. It was an active support and used air cylinders to provide accurate unloading force. First, the design flow of gravity unloading was introduced;then the detailed design of the mechanical structure and control system was given;then the performance parameters of the two types of cylinders were tested and compared, including the force-pressure relationship curve and the force-position relationship curve;finally, the experimental verification of the gravity unloading device was carried out;for a mirror with an aperture of ?2100 mm, the gravity unloading device was designed and a vertical detection optical path was built. The test results showed that by using this gravity unloading device, the actual processing surface accuracy of the mirror was better than 1/50λ-RMS, which met the application requirement of the optical system. Thus, it can be seen that using this gravity unloading device can effectively unload the gravity of the mirror and realize the accurate processing and measurement of the mirror surface. .

低温条件下提高连续混配施工稳定性研究

长庆油田水平井施工方式以连续混配为主,但是在冬季低温情况下,胍胶溶胀差,基液黏度低,交联液携砂能力差,达不到施工要求。室内研究表明,通过调整配液p H值、添加剂添加顺序、延长胍胶溶胀时间等方法,配制携砂液交联性能好。现场施工过程中,提前把胍胶基液用水pH值调整到合理值;增加缓冲罐,提前配制胍胶基液,延长溶胀时间;调整添加剂添加顺序等方式,现场施工表明交联液携砂能力好,满足施工要求。

多倍体与二倍体枇杷叶片特征及抗旱性初步分析

【目的】探讨多倍体与二倍体枇杷(Eriobotrya japonica Lindl.)叶片生理形态特征差异并进行抗旱性初步评价,为枇杷倍性鉴定及抗旱性评价提供参考。【方法】以4个系列18个不同倍性枇杷株系为试验材料,对各株系叶片的形态解剖结构、失水率(RWL)、营养元素含量、叶绿素(Chl)含量进行观察、测定和分析。通过隶属函数法,对其抗旱能力进行初步评价。【结果】枇杷叶片长度、宽度与倍性呈极显著正相关(p<0.01),叶形指数与倍性呈极显著负相关(p<0.01);10项枇杷叶片解剖结构指标与倍性关联度强弱排序依次为:下表皮、上角质层、海绵组织、叶片组织细胞结构疏松度(SR)、叶厚、叶片组织细胞结构紧密度(CTR)、下角质层、栅栏组织、栅栏组织细胞层数、上表皮,其中上角质层、下角质层、CTR与倍性呈负相关;在40℃下干旱处理6 h后,A系列、H系列、K系列失水率与倍性均呈负相关,在24 h后失水率与倍性呈显著负相关(p<0.05);氮(N)、磷(P)、钾(K)、铁(Fe)、叶绿素a(Chl.a)、叶绿素b(Chl.b)、总叶绿素含量Chl.(a+b)含量与倍性关联度强弱排序依次为:N、K、P、Chl.b、Chl.(a+b)、Fe、Chl.a,其中N、P、K含量与倍性呈负相关;参考枇杷叶片解剖结构与失水率进行抗旱性隶属函数分析:‘A313’(3x)、‘A322’(3x)、‘B350’(3x)、‘B431’(4x)、‘4X(2)’(4x)、‘H324’(3x)、‘K3’(3x)、‘K4’(4x)抗旱性均强于同系列二倍体。【结论】枇杷叶片生理形态指标可作为枇杷倍性鉴定的参考指标,抗旱性评价中的8个抗旱性强的多倍体枇杷材料可用于进一步抗旱性研究,培育多倍体可作为提高枇杷抗旱性的一种途径。

柴油机尾气中的碱性无机污染物引起Cu-SAPO-18脱硝催化剂的化学失活（英文）

选择性催化还原NO_x (NH_3-SCR)已是柴油机尾气处理系统中有效的NO_x减排技术.铜基分子筛催化剂作为潜在的NH_3-SCR催化剂已被广泛研究,其中具有AEI结构的Cu-SAPO-18分子筛表现出优异的脱硝活性和水热稳定性,成为柴油机尾气后处理系统潜在的替代品.然而在实际的后处理应用中,生物柴油污染物、发动机润滑剂和燃料添加剂中的一些无机组分(K, Na, S, P, Ca和Mg等)可逐渐聚集在催化剂表面,导致催化剂孔道堵塞和活性位点丢失,最终导致SCR催化剂失活.由于碱金属和碱土金属在柴油衍生物中含量较高,因而其对SCR催化剂的影响引起了人们更多的关注.本文采用浸渍法制备了掺杂不同含量碱性无机污染物(K, Na, Ca和Mg)的Cu-SAPO-18催化剂,以阐明这些污染物对Cu-SAPO-18结构、酸性位点和铜物种的影响.XRD和氮吸附实验结果表明,低含量污染物的掺入造成催化剂孔道堵塞和比表面积下降,而高含量污染物引入导致催化剂部分结构被破坏,其中高含量Na的引入造成催化剂结构破坏最为严重.H_2-TPR和EPR结果表明,污染物引入Cu-SAPO-18后,催化剂的Cu^(2+)数目减少,这是由于Cu^(2+)被K^+, Na^+, Ca^(2+)和Mg^(2+)取代造成的.被取代的Cu^(2+)由于无法位于离子交换位点上会在煅烧过程中转变成CuO和CuAl_2O_4, CuO的产生会造成催化剂孔道堵塞甚至部分骨架结构坍塌.另外,NH_3-TPD结果表明,与新鲜催化剂相比,被污染的Cu-SAPO-18催化剂总酸性位点减少,这是由于H^+和Cu^(2+)被K^+, Na^+, Ca^(2+)和Mg^(2+)取代造成Br?nsted酸和Lewis酸减少造成的.催化剂比表面积的降低、Cu^(2+)数目以及酸含量的减少最终造成催化剂失活,且催化剂失活程度随无机污染物含量的增加而增大.但不同无机组分造成催化剂的失活程度不同,其中K, Na, Ca和Mg造成Cu-SAPO-18催化剂失活程度为K> Na> Ca> Mg.此外, K, Na, Ca和Mg造成Cu-SAPO-18催化剂比表面积、Cu^(2+)含量以及酸含量的减少程度分别为Na> K> Ca> Mg, Na> K> Mg> Ca和K> Na> Ca> Mg.其中酸含量下降程度与催化剂失活程度一致,表明在某种程度上,酸含量对催化剂NH_3-SCR活性的影响高于催化剂结构和Cu^(2+)对活性的影响.最后,我们还通过NH3-SCR动力学测试研究了K, Na, Ca和Mg对Cu-SAPO-18催化NH_3-SCR反应机理的影响,结果显示新鲜催化剂和被污染催化剂具有相近的活化能,表明无机污染物对Cu-SAPO-18催化NH3-SCR反应机理没有影响.

鼻咽癌治疗相关听力损伤研究进展

鼻咽癌治疗相关听力损伤已成为治疗后的常见并发症之一,其听力损伤可表现为传导性听力下降、感音神经性听力下降或混合性听力下降。研究表明,放射线、化疗药物(主要是顺铂)具有耳毒性,且二者耳毒性具有协同作用。文章阐述放射线、化疗药物(以顺铂为主)的听力损伤机制,辐射剂量、顺铂剂量与听力损伤关系,以及听力损伤的预防和治疗,旨在提高对鼻咽癌治疗后听力损伤的认识,唤起对听功能保护的重视。

Is seawater geochemical composition recorded in marine carbonate? Evidence from iron and manganese contents in Late Devonian carbonate rocks

Iron and manganese are the important redoxsensitive elements in the ocean. Previous studies have established a series of paleo-depositional redox proxies based on the form and content of iron in sedimentary rocks(e.g., degree of pyritization, FeHR/FeT, Fe/Al). These proxies were developed and applied on siliciclastic-rich marine sediments. Although marine carbonate rocks are generally considered to preserve the geochemical signals of ancient seawater, neither Fe nor Mn content in marine carbonate rocks(Fecarb, Mncarb) has been independently used as a proxy to quantify environmental cues in paleo-oceans. Both Fe and Mn are insoluble in oxic conditions(Fe_2O_3, Fe(OH)_3,MnO_2), while their reduced forms(Fe^(2+) and Mn^(2+)) are soluble. Therefore, oxic seawater should have low concentrations of dissolved Fe^(2+)and Mn^(2+), and accordingly carbonate rocks precipitated from oxic seawater should have low Fecarband Mncarb, and vice versa. To evaluate whether Fecarband Mncarbcan be used to quantify oxygen fugacity in seawater, we measured Fecarband Mncarbof Upper Devonian marine carbonate rocks collected from nine sections in South China. Fecarbof intraplatform basin samples wassignificantly higher than that of shelf samples, while shelf and basin samples had comparable Mncarb. The modeling result indicates that the dramatic difference in Fecarbcannot be explained by variation in oxygen fugacity between the shelf and basin seawater. Instead, both Fecarband Mncarb appear to be more sensitive to benthic flux from sediment porewater that is enriched in Fe^(2+)and Mn^(2+). Porewater Fe^(2+)and Mn^(2+)derive from bacterial iron and manganese reduction; flux was controlled by sedimentation rate and the depth of the Fe(Mn) reduction zone in sediments, the latter of which is determined by oxygen fugacity at the water–sediment interface. Thus, high Fecarbof the basin samples might be attributed to low sedimentation rate and/or low oxygen fugacity at the seafloor. However, invariant Mncarbof the shelf and basin samples might be the consequence of complete reduction of Mn in sediments. Our study indicates that marine carbonate rocks may not necessarily record seawater composition, particularly for benthic carbonate rocks. The influence of benthic flux might cause carbonate rocks' geochemical signals to deviate significantly from seawater values. Our study suggests that interpretation of geochemical data from carbonate rocks, including carbonate carbon isotopes, should consider the process of carbonate formation.

Diagnostic classification of endosonography for differentiating colorectal ulcerative diseases: A new statistical method

AIM To establish a classification method for differential diagnosis of colorectal ulcerative diseases, especially Crohn's disease(CD), primary intestinal lymphoma(PIL) and intestinal tuberculosis(ITB).METHODS We searched the in-patient medical record database for confirmed cases of CD, PIL and ITB from 2008 to 2015 at our center, collected data on endoscopic ultrasound(EUS) from randomly-chosen patients who formed the training set, conducted univariate logistic regression analysis to summarize EUS features of CD, PIL and ITB, and created a diagnostic classification method. All cases found to have colorectal ulcers using EUS were obtained from the endoscopy database and formed the test set. We then removed the cases which were easily diagnosed, and the remaining cases formed the perplexing test set. We re-diagnosed the cases in the three sets using the classification method, determined EUS diagnostic accuracies, and adjusted the classification accordingly. Finally, the re-diagnosing and accuracy-calculating steps were repeated.RESULTS In total, 272 CD, 60 PIL and 39 ITB cases were diagnosed from 2008 to 2015 based on the in-patient database, and 200 CD, 30 PIL and 20 ITB cases were randomly chosen to form the training set. The EUS features were summarized as follows: CD: Thickened submucosa with a slightly high echo level and visible layer; PIL: Absent layer and diffuse hypoechoic mass; and ITB: Thickened mucosa with a high or slightly high echo level and visible layer. The test set consisted of 77 CD, 30 PIL, 23 ITB and 140 cases of other diseases obtained from the endoscopy database. Seventy-four cases were excluded to form the perplexing test set. After adjustment of the classification, EUS diagnostic accuracies for CD, PIL and ITB were 83.6%(209/250), 97.2%(243/250) and 85.6%(214/250) in the training set, were 89.3%(241/270), 97.8%(264/270) and 84.1%(227/270) in the test set, and were 86.7%(170/196), 98.0%(192/196) and 85.2%(167/196) in the perplexing set, respectively.CONCLUSION The EUS features of CD, PIL and ITB are different. The diagnostic classification method is reliable in the differential diagnosis of colorectal ulcerative diseases.

Slow-pull and different conventional suction techniques in endoscopic ultrasound-guided fine-needle aspiration of pancreatic solid lesions using 22-gauge needles

AIM To evaluate the cytological diagnostic capacity and sample quality of the slow-pull technique and compare them with different suction techniques.METHODS From July 2010 to December 2015, 102 patients with pancreatic solid lesions who underwent endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA) with 22-gauge needles were retrospectively evaluated. EUS-FNA diagnosis was based on a cytological examination, and final diagnosis was based on a comprehensive standard of cytological diagnosis, surgical pathology and clinical or imaging follow-up. Cytological specimens were characterized for cellularity and blood contamination. The cytological diagnostic capacity and sample quality of the slow-pull technique and suction techniques with 5-m L/10-m L/20-m L syringes were analyzed.RESULTS Of all of the EUS-FNA procedures, the slow-pull technique and suction techniques with 5-m L/10-m L/20-m L syringes were used in 31, 19, 34 and 18 procedures, respectively. There were significant differences between these four suction techniques in terms of cytological diagnostic accuracy(90.3% vs 63.2% vs 58.8% vs 55.6%, P = 0.019), sensitivity(88.2% vs 41.7% vs 40.0% vs 36.4%, P = 0.009) and blood contamination(score ≥ 2 for 29.0% vs 52.6% vs 70.6% vs 72.2%, P = 0.003). The accuracy and sensitivity of the slow-pull technique were significantly higher than those of the suction techniques using 5-m L(P = 0.03, P = 0.014), 10-m L(P = 0.005; P = 0.006) and 20-mL syringes(P = 0.01, P = 0.01). Blood contamination was significantly lower in the slow-pull technique than in the suction techniques with 10-m L(P = 0.001) and 20-mL syringes(P = 0.007).CONCLUSION The slow-pull technique may increase the cytological diagnostic accuracy and sensitivity with slight blood contamination during EUS-FNA when using 22-gauge needles for solid pancreatic masses.

Oxygen vacancies enriched nickel cobalt based nanoflower cathodes: Mechanism and application of the enhanced energy storage

The rational design of oxygen vacancies and electronic microstructures of electrode materials for energy storage devices still remains a challenge. Herein, we synthesize nickel cobalt-based oxides nanoflower arrays assembled with nanowires grown on Ni foam via the hydrothermal process followed annealing process in air and argon atmospheres respectively. It is found that the annealing atmosphere has a vital influence on the oxygen vacancies and electronic microstructures of resulting NiCo_(2)O_(4) (NCO-Air) and CoNiO_(2) (NCO-Ar) products, which NCO-Ar has more oxygen vacancies and larger specific surface area of 163.48 m^(2)/g. The density functional theory calculation reveals that more oxygen vacancies can provide more electrons to adsorb –OH free anions resulting in superior electrochemical energy storage performance. Therefore, the assembled asymmetric supercapacitor of NCO-Ar//active carbon delivers an excellent energy density of 112.52 Wh/kg at a power density of 558.73 W/kg and the fabricated NCO-Ar//Zn battery presents the specific capacity of 180.20 mAh/g and energy density of 308.14 Wh/kg. The experimental measurement and theoretical calculation not only provide a facile strategy to construct flower-like mesoporous architectures with massive oxygen vacancies, but also demonstrate that NCO-Ar is an ideal electrode material for the next generation of energy storage devices.

Calculation and decomposition of regional household energy consumption in China:based on perspectives of urbanization and residents' consumption

Demographic urbanization caused great changes in scale of residents' consumption and residents' lifestyle and then impacted changes of regional household energy consumption. This paper expanded Logarithmic Mean Decomposition Index method through introducing variables of urbanization and residential consumption into the model. It also analyzed the influences of six factors as energy structure, energy intensity, population scale, urbanization, residential consumption, and consumption inhibit on regional household energy consumption. Results showed that in 2003-2012, impact of urbanization on regional household energy consumption of Chinese three areas was significantly higher than population size. The "population gathered in eastern region" phenomenon caused eastern region getting the largest population scale effect. Driving force of residential consumption on regional household energy consumption was much higher than the other five effects. Due to the comparative advantage of residential consumption compared with government consumption, investment, and net export, the decrease of consumption ratio promoted the growth of regional household energy consumption. Energy intensity in Chinese three regions kept reducing in 2003-2012. The progress of energy utilization technology slowed the growth of regional household energy consumption, and energy intensity effect was most significant in the central region.

Carbon and nitrogen budget in fish-polychaete integrated aquaculture system

Integrated multi-tropic aquaculture(IMTA)systems have been used in China for many years and have achieved significant economic,social,and ecological benefits.However,there is still a lack of benthic bioremediation species that can effectively utilize the aquaculture particulate organic waste in the system.Polychaete Perinereis aibuhitensis Grube is used as an environmental remediation species for large-scale aquaculture to reduce particulate organic waste,which is of great significance to environmental protection.To improve bio-elements utilization efficiency,P.aibuhitensis was applied for IMTA indoor fish(Hexagrammos otakii)farming.Results showed that in the system,production of 1 kg of the fish discharged 2141-2338 mg of carbon and 529-532 mg of nitrogen,while in the monoculture of the fish,the figures were 3033-3390 mg and 764-794 mg,or 24.84%-35.26%and 30.35%-33.32%less,respectively.This approach promoted IMTA technology that could utilize the particulate organic waste from intensive aquaculture and reduce the adverse environmental effects.

欧洲热电业的现状和前景

介绍欧盟热电产业的概况,特别是热电联产技术的发展现状、潜力和前景,分析了影响热电发展的相关政策,同时介绍了一些欧盟成员国采取的各种鼓励措施。强调热电业的进一步发展必须与欧盟能源政策的三大目标相一致:即保障能源供应、提高工业竞争力、保护环境,这些目标的实施对实现经济可持续发展和环境保护是非常必要的。

East Asian VLBI Network observations of active galactic nuclei jets:imaging with KaVA+Tianma+Nanshan

The East Asian Very Long Baseline Interferometry(VLBI) Network(EAVN) is a rapidly evolving international VLBI array that is currently promoted under joint efforts among China,Japan and Korea.EAVN aims at forming a joint VLBI Network by combining a large number of radio telescopes distributed over East Asian regions.After the combination of the Korean VLBI Network(KVN) and the VLBI Exploration of Radio Astrometry(VERA) into Ka VA,further expansion with the joint array in East Asia is actively promoted.Here we report the first imaging results(at 22 and 43 GHz) of bright radio sources obtained with Ka VA connected to Tianma 65-m and Nanshan 26-m Radio Telescopes in China.To test the EAVN imaging performance for different sources,we observed four active galactic nuclei(AGN) having different brightness and morphology.As a result,we confirmed that the Tianma 65-m Radio Telescope(TMRT) significantly enhances the overall array sensitivity,a factor of 4 improvement in baseline sensitivity and 2 in image dynamic range compared to the case of Ka VA only.The addition of the Nanshan 26-m Radio Telescope(NSRT) further doubled the east-west angular resolution.With the resulting high-dynamic-range,high-resolution images with EAVN(Ka VA+TMRT+NSRT),various fine-scale structures in our targets,such as the counter-jet in M87,a kink-like morphology of the 3 C 273 jet and the weak emission in other sources are successfully detected.This demonstrates the powerful capability of EAVN to study AGN jets and to achieve other science goals in general.Ongoing expansion of EAVN will further enhance the angular resolution,detection sensitivity and frequency coverage of the network.

Model-Synthesized Rate of Type Ia Supernovae and its Influence on the Chemical Enrichment of the ISM

Using Hurley's rapid binary stellar evolution code, we have studied the model- synthesized rate of Type Ia Supernovae (SNe Ia) and its influence on the chemical enrichment of the interstellar medium ejected by stellar populations. We adopt two popular scenarios, i.e., single degenerate scenario (SD) and double degenerate scenario (DD), for the progenitors of SNe Ia to calculate the rates of SNe Ia. Rates calculated in this work agree with that of Hachisu et al. and Han & Podsiadlowski, but are different from that usually adopted in chem- ical evolution models of galaxies. We apply the rates of SNe Ia to the chemical enrichment (especially Fe enrichment), then compare the results with previous studies. As known SNe Ia slightly affect the enrichment of C, N, O and Mg elements, while significantly affect the en- richment of Fe. We find that the occurrence and the value of the Fe enrichment in our models are earlier and smaller than that commonly adopted in chemical evolution models. We also study the evolution of [Mg/Fe] ratios, which are almost reciprocals of the Fe enrichment. The study may provide constraints on the free parameters of chemical evolution models of galaxies and evolutionary population synthesis.

Discipline Planning of the Modern Glass Art

The main purpose of establishing the glass art discipline in colleges and universities is to further promote the long-term development of the glass art discipline in China,and develop more talents in this field to meet the demand of social development.Nowadays,as the promotion and popularization of glass teaching subjects,the whole level of glass art teaching has also been effectively enhanced,the abundant rich ethnic culture it contains supplies more nutrition and inspiration to the explorers.Based on this,this paper makes analysis on the planning of modern glass art for reference.

The Optimal Allocation of Investment between Antivirals and Vaccines for Influenza Pandemic Preparedness Planning

Objectives To investigate that given a fixed amount of financial resources,what is the optimal combination of vaccine and antiviral stockpiles in terms of minimizing the attack rate.Methods Mathematic modeling was used to simulate the dynamics that with fixed influenza pandemic budget.Different budget conditions were observed if the combination changed.Framework between vaccines and antivirals was introduced by taking into account the uncertainty in vaccine and antiviral efficacy.Results Given a fixed budget,different budget allocations between vaccines and antivirals stockpile gave different attack rates.When the price of vaccine was lower than or similar with the antivirals,the attack rate increased with increasing investment in antiviral.But if the price of the vaccine was higher than the antivirals,the attack rate may not decrease with increasing investment in vaccine.Fixed the vaccine effectiveness,higher effectiveness of antiviral got a lower attack rate.When both antiviral and vaccine were with 50%probability of effectiveness,the attack rate changed by antiviral stockpile with a same pattern as they were with 100%efficacy probability,even it has a higher attack rate.Conclusions Assume the antivirals have 100%probability to be effective,budget was limited to a fix number,then in any event,population should stockpile a small amount of antivirals such that if the post-vaccination reproductive number turns out to be near 1,the additional intervention may further reduce the reproductive number to <1 and prevent the epidemic.Under the fixed budget,the price of the vaccines and antivirals will strongly affect the strategy of the stockpile allocation.When the price of vaccine is comparative lower,more investment of vaccine is better for the pandemic control,but if the vaccine price is too high then more investment in antiviral may be better.We found that attack rates and the optimal budget allocation depend on the probability to be effective of vaccine and antivirals.

Devonian integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

The Devonian System in the Qinghai-Tibetan Plateau and its surrounding areas is widely distributed,diverse in lithotypes and rich in fossils.It records the crucial processes of continuous subduction and reduction of the Paleo-Asian Ocean in the northern hemisphere and the transformation of the Proto-Tethys Ocean into the Paleo-Tethys Ocean in the southern hemisphere.Thus,it is of great significance for explaining the global paleogeographic evolution,tectonic activities and biodiversity changes during this critical period.The blocks on both sides of the southern Tienshan suture zone and the Longmu Co-ShuanghuChangning-Menglian suture zone belong to different sedimentary systems and paleobiogeographic realms and regions,showing important tectonic paleogeographic partitioning significance.The two suture zones represent the main branches of the PaleoAsian Ocean and the Paleo-Tethys Ocean,respectively,and on this basis the Devonian System can be subdivided into three types:the Tienshan type,the Tethys type and the Gondwana type.Based on recent research progress on the Devonian stratigraphy and paleontology in combining provenance analysis and biotic characteristics in the Qinghai-Tibetan Plateau and surrounding areas,this paper aims to establish the latest integrative stratigraphic framework and conduct paleogeographic reconstruction,providing foundation for exploring the geological evolution and dynamic mechanisms of various terranes and blocks in the northern margin of Gondwana.The results indicate that the North Qiangtang,South Qiangtang,Simao,Baoshan and Tengchong terranes,as well as the Himalaya Tethys Zone and the South China Block have affinities with the Indian Block,while the Lhasa Terrane has affinities with the Australian Block,and may be located between the South China and Australian blocks.In the Emsian(Early Devonian),the South China Block separated from the northern margin of Gondwana,a process that was accompanied by the opening of the Jinshajiang-Ailaoshan Ocean.In the Middle Devonian,the mid-oceanic ridge of the Paleo-Tethys Ocean expanded rapidly,corresponding with a global sea-level rise,the widespread development of carbonate platforms and nadir values of Devonian seawater strontium isotopes.By the Late Devonian,the Paleo-Tethys Ocean had reached a considerable size,leading to abundant occurrences of Upper Devonian radiolarian cherts in the Paleo-Tethys suture zones.

基于光滑有限元法的热-弹相场断裂研究

基于相场理论,论文构建了热力耦合作用下热-弹性材料的复杂断裂控制方程,采用光滑有限元法对该模型进行了数值离散;设计编写了相应的Matlab计算程序;开展了热-力载荷下的二维拉伸断裂模拟,将结果和有限元计算结果对比,吻合一致.同时采用该模型开展热冲击下陶瓷板的多裂纹扩展过程模拟,计算结果和实验结果吻合良好,验证了论文方法的有效性.

Efficacy and safety of Kangxian Huanji Granule as adjunctive treatment in acute exacerbation of idiopathic pulmonary fibrosis:An exploratory randomized controlled trial

Background:Acute exacerbation of idiopathic pulmonary fibrosis(AE-IPF)is an important occurrence in the natural history of idiopathic pulmonary fibrosis(IPF),associated with high hospitalization rates,high mortality and poor prognosis.At present,there is no effective treatment for AE-IPF.Chinese herbal medicine has some advantages in treating IPF,but its utility in AE-IPF is unclear.Objective:The treatment of AE-IPF with Kangxian Huanji Granule(KXHJ),a compound Chinese herbal medicine,lacks an evidence-based justification.This study explores the efficacy and safety of KXHJ in patients with AE-IPF.Design,setting,participants and interventions:Wedesigned a randomized,double-blind,placebo-controlled,exploratory clinical trial.A total of 80 participants diagnosed with AE-IPF were randomly assigned to receive KXHJ or a matching placebo;the treatment included a 10 g dose,administered twice daily for 4 weeks,in addition to conventional treatment.Participants were followed up for 12 weeks after the treatment.Main outcome measures:The primary endpoints were treatment failure rate and all-cause mortality.Secondary endpoints included the length of hospitalization,overall survival,acute exacerbation rate,intubation rate,the modified British Medical Research Council(mMRC)score,and the St George’s Respiratory Questionnaire for IPF(SGRQ-I)score.Results:The rate of treatment failure at 4 weeks was lower in the intervention groupcompared to the control group(risk ratio[RR]:0.22;95%confidence interval[CI]:0.051 to 0.965,P=0.023).There was no significant difference in all-causemortality at 16 weeks(RR:0.75;95%CI:0.179 to 3.138;P>0.999)or in the acute exacerbation rate during the 12-week follow-up period(RR:0.69;95%CI:0.334 to 1.434;P=0.317).The intervention group had a shorter length of hospitalization than the control group(mean difference[MD]:–3.30 days;95%CI,–6.300 to–0.300;P=0.032).Significant differences in the mean change from baseline in the mMRC(between-group difference:–0.67;95%CI:–0.89 to–0.44;P<0.001)and SGRQ-I score(between-group difference:–10.36;95%CI:–16.483 to–4.228;P=0.001)were observed after 4 weeks,and also in the mMRC(between-group difference:–0.67;95%CI:–0.91 to–0.43;P<0.001)and SGRQ-I(between-group difference:–10.28;95%CI,–15.838 to–4.718;P<0.001)at 16 weeks.The difference in the adverse events was not significant.Conclusion:KXHJ appears to be effective and safe for AE-IPF and can be considered a complementary treatment in patients with AE-IPF.As a preliminary exploratory study,our results provide a basis for further clinical research.

Comparison of Clinical Characteristics and Outcomes of MAFLD and NAFLD in Chinese Health Examination Populations

Background and Aims:The recently proposed concept of metabolic dysfunction-associated fatty liver disease(MAFLD)has remained controversial.We aimed to describe the features and associated outcomes to examine the diagnostic ability of MAFLD for identifying high-risk individuals.Methods:In this retrospective cohort study,we enrolled 72,392 Chinese participants between 2014 and 2015.Participants were classified as MAFLD,nonalcoholic fatty liver disease(NAFLD),non-MAFLD-NAFLD,and a normal control group.The primary outcomes were liver-related and cardiovascular disease(CVD)events.Person-years of follow-up were calculated from enrolment to the diagnosis of the event,or the last date of data(June,2020).Results:Of the 72,392 participants,31.54%(22,835)and 28.33%(20,507)qualified the criteria for NAFLD or MAFLD,respectively.Compared with NAFLD,MAFLD patients were more likely to be male,overweight,and have higher biochemical indices including liver enzyme levels.Lean MAFLD diagnosed with≥2 or≥3 metabolic abnormalities presented similar clinical manifestations.During the median follow-up of 5.22 years,919 incident cases of severe liver disease and 2,073 CVD cases were recorded.Compared with the normal control group,the NAFLD and MAFLD groups had a higher cumulative risk of liver failure and cardiac-cerebral vascular diseases.There were no significant differences in risk between the non-MAFLD-NAFLD and normal group.Diabetes-MAFLD group had the highest incidence of liver-related and cardiac-cerebral vascular diseases,lean MAFLD came second,and obese-MAFLD had the lowest incidence.Conclusions:This real-world study provided evidence for rationally assessing the benefit and practicability of the change in terminology from NAFLD to MAFLD.MAFLD may be better than NAFLD in identifying fatty liver with worse clinical features and risk profile.