Numerical analysis of downward progressive landslides in long natural slopes with sensitive clay

Landslides occurring in sensitive clay often result in widespread destruction,posing a significant risk to human lives and property due to the substantial decrease in undrained shear strength during deformation.Assessing the consequences of these landslides is challenging and necessitates robust numerical methods to comprehensively investigate their failure mechanisms.While studies have extensively explored upward progressive landslides in sensitive clays,understanding downward progressive cases remains limited.In this study,we utilised the nodal integration-based particle finite element method(NPFEM)with a nonlinear strain-softening model to analyse downward progressive landslides in sensitive clay on elongated slopes,induced by surcharge loads near the crest.We focused on elucidating the underlying failure mechanisms and evaluating the effects of different soil parameters and strainsoftening characteristics.The simulation results revealed the typical pattern for downward landslides,which typically start with a localised failure in proximity to the surcharge loads,followed by a combination of different types of failure mechanisms,including single flow slides,translational progressive landslides,progressive flow slides,and spread failures.Additionally,inclined shear bands occur within spread failures,often adopting distinctive ploughing patterns characterised by triangular shapes.The sensitive clay thickness at the base,the clay strength gradient,the sensitivity,and the softening rate significantly influence the failure mechanisms and the extent of diffused displacement.Remarkably,some of these effects mirror those observed in upward progressive landslides,underscoring the interconnectedness of these phenomena.This study contributes valuable insights into the complex dynamics of sensitive clay landslides,shedding light on the intricate interplay of factors governing their behaviour and progression.

The Macrolichens of Barluk Mountain National Nature Reserve, Xinjiang Province, China

A checklist of the macrolichens (foliose, fruticose & squamulose) of Barluk Mountain National Nature Reserve located in northwestern China is presented. It was derived from 47 inventories of preserved and undeveloped areas which yielded more than 670 collections containing 102 taxa (99 species, 1 subspecies, 2 varieties). Eight species were found that were new to Xinjiang, China. Twenty-eight species and 2 varieties were found on rock, 31 species on bark of deciduous and coniferous trees, 26 species on soil and 14 species and 1 subspecies over mosses. Foliose lichens were dominant with 76 species, followed by 16 species of squamulose lichens and 7 species of fruticose lichens.

博士后对学术职业环境满意吗?——基于Nature全球博士后调查数据比较分析

本研究基于已有成果,将博士后学术职业环境划分为学术资源、职业保障、组织管理、科研强度四个维度。利用2020年Nature全球博士后教育调查数据,通过比较分析博士后对学术职业环境的感知与评价。研究发现,相比较国外发达国家博士后而言,我国接近四成博士后对学术职业环境感到满意。为了优化博士后学术职业环境,大学需强化对博士后科研资金的支持力度,保障博士后科研参与机会,减少非学术事务对博士后科研时间的挤占,规范导师指导;大学不断调适大学基层学术组织治理模式,优化院系对博士后学术职业发展的组织支持与服务质量;大学与博士后建立稳定性雇佣关系,不断提升工资薪酬水平,疏通博士后学术职业晋升渠道,营造良好的工作环境;高校实行服务型、便捷式的科研管理方式,制定灵活多元的学术评价机制,破除博士后对“学术GDP主义”的崇拜。

Nature's disguise:Empirical demonstration of dead-leaf masquerade in Kallima butterflies

Animals deploy diverse color-based defenses against predators,including crypsis,mimicry,aposematism,and masquerade.While crypsis,mimicry,aposematism have been extensively studied,the strategy of masquerade-where organisms imitate inedible or inanimate objects such as leaves,twigs,stones,and bird droppings-remains comparatively underexplored,particularly in adult butterflies.The Indian oakleaf butterfly(Kallima inachus)exemplifies this phenomenon,with its wings resembling dead leaves,providing a classic example of natural selection.Although it has long been postulated that these butterflies evade predation by being misidentified as dead leaves,direct experimental evidence is lacking.In the current study,using domestic chicks as predators,we manipulated their prior experience with dead leaves(model objects)while maintaining constant exposure to butterflies to test whether dead-leaf masquerade provides a protective advantage by preventing recognition.Results showed a marked delay in the initiation of attacks by chicks familiar with dead leaves compared to those with no prior exposure or those exposed to visually altered leaves.Chicks with prior dead-leaf experience required a similar amount of time to attack the butterflies as they did to attack dead leaves.These findings provide the first empirical demonstration of dead-leaf masquerade in Kallima butterflies,shedding light on its evolutionary significance.Our study highlights the effectiveness of masquerade in inducing the misclassification of butterflies as inanimate objects,showcasing the precise mimicry achieved by these organisms when viewed in isolation from the model objects.This study advances our understanding of the evolution of masquerade and its role as a potent antipredator strategy in nature.

Zhang Jiebin-Master of the School of Tonifying with Medicinals Warm in Nature

Zhang Jiebin,also known as Zhang Huiqing and Zhang Jingyue(1563-1640 AD)was from Shanyin(today's Shaoxing,Zhejing Province).People usually call him Zhang Jingyue.He was a famous medical theorist,clinician and the representative personage of the School of Tonifying with Medicinals Warm in Nature.He is the author of The Classified Classic(Lei Jing),Jingyue's Complete Works(Jing Yue Quan Shu),etc.

Adaptive Network Sustainability and Defense Based on Artificial Bees Colony Optimization Algorithm for Nature Inspired Cyber Security

Cyber Defense is becoming a major issue for every organization to keep business continuity intact.The presented paper explores the effectiveness of a meta-heuristic optimization algorithm-Artificial Bees Colony Algorithm(ABC)as an Nature Inspired Cyber Security mechanism to achieve adaptive defense.It experiments on the Denial-Of-Service attack scenarios which involves limiting the traffic flow for each node.Businesses today have adapted their service distribution models to include the use of the Internet,allowing them to effectively manage and interact with their customer data.This shift has created an increased reliance on online services to store vast amounts of confidential customer data,meaning any disruption or outage of these services could be disastrous for the business,leaving them without the knowledge to serve their customers.Adversaries can exploit such an event to gain unauthorized access to the confidential data of the customers.The proposed algorithm utilizes an Adaptive Defense approach to continuously select nodes that could present characteristics of a probable malicious entity.For any changes in network parameters,the cluster of nodes is selected in the prepared solution set as a probable malicious node and the traffic rate with the ratio of packet delivery is managed with respect to the properties of normal nodes to deliver a disaster recovery plan for potential businesses.

《Nature》揭示:禁食机制下的脂肪依赖性肿瘤会消退

近日,一篇发表在《Nature》上的研究显示,研究发现了一种能让小鼠摆脱胰腺癌的新方法,该疗法通过抑制脂肪代谢,切断肿瘤的能量供应,只要小鼠持续遵循生酮饮食,肿瘤生长便会停滞。研究中,研究团队聚焦于机体在禁食状态下如何转向脂肪作为能源的问题。研究者发现直接关联到胰腺癌的生物学研究,首次揭示了真核生物翻译起始因子(eukaryotic translation initiation factor,eIF4E)在禁食期间如何调控机体代谢,使其从消耗碳水化合物转变为消耗脂肪。

《Nature》子刊:苏佳琪等开发基于牛奶的水凝胶,用作酒精中毒的解毒剂

近日,苏黎世联邦理工学院Raffaele Mezzenga、苏佳琪等人在《Nature》子刊《Nature Nanotechnology》上发表的一篇研究显示,该研究开发了一种口服的、基于牛奶蛋白的水凝胶——FeSA@FibBLG,或可作为急性酒精中毒的有效解毒剂,能够稳定耐受胃酸消化且持续显著降低酒精中毒小鼠血液中的酒精水平,同时避免额外积累有毒的乙醛,还可增强肝脏保护,并显著减轻肠道损伤和生态失调,强调了其作为酒精相关疾病的新疗法的潜力。

《Nature》:新开发的可穿戴超声贴片可连续、无创监测大脑血流

近日,一篇发表在《Nature》上的研究显示,研究人员开发出一种可穿戴超声贴片(wearable ultrasound patch),其可对大脑血流进行连续、无创的监测。该研究将贴片在36名健康志愿者身上进行了测试,以检验其测量脑部主要动脉血流速度(收缩期峰值、平均流速和舒张末期速度)的能力,发现测量结果与传统超声探头的测量结果非常吻合。

《Nature》:科学家发现能驱动患者狼疮发生的两种细胞缺陷

近日,一篇发表在《Nature》上的研究显示,研究发现了一种特殊的分子缺陷或会促进系统性红斑狼疮的病理性免疫反应,同时揭示了逆转这一缺陷或有望逆转疾病。该研究中,研究人员报道了驱动狼疮发生的新通路,研究者表示,患者体内血液中的多种分子都会发生疾病相关的改变,最终,这些变化会导致芳香烃受体(aryl hydrocarbon receptor,AHR)所控制的通路激活不足,AHR能调节细胞对环境污染物、细菌或代谢产物的反应。

The Alienation of Nature in Emily Dickinson’s Poems through the Prism of Taoism

In the poems created by the renowned American poet Emily Dickinson,those related to nature constitute a considerable proportion.However,Dickinson’s attitude toward nature is,in fact,contradictory.On the one hand,Dickinson perceives nature as gentle and kind,akin to a mother.Nature is regarded as“heaven”and embodies harmony.On the other hand,nature possesses its own operational principles and harbors inherent cruelty.According to Dickinson,humans should refrain from excessive interference in the natural order.This article attempts to analyze the similarities in attitude towards nature between Dickinson’s poetry and Taoist philosophy.

Problems and Development Suggestions of Nature Education in Jiangxi Province

The forest coverage rate of Jiangxi Province ranks second in China.It has rich natural resources,a long history of ancient color culture and rich red culture.In the development of nature education,Jiangxi Province has great potential and advantages.This paper introduces the development conditions of nature education in Jiangxi Province,summarizes the problems existing in the development of nature education in Jiangxi Province from the aspects of the types of nature education and the construction of nature education base,such as simple content and single form,imperfect infrastructure and lack of professionals,and puts forward some suggestions on the development of nature education in Jiangxi Province.

The Exploration of Human Nature in Young Goodman Brown

Taking Nathaniel Hawthorne’s Young Goodman Brown as an example,this paper analyzes the Puritan thought of“inherently evil human nature”embodied by the main characters in the work.Through the analysis of characters,such as Brown,Faith,and the mysterious old man,it shows the evil under Brown’s loyal and kind appearance,the devilish nature under Faith’s angelic appearance,and the evil of human nature revealed by everyone’s participation in the devil’s appointment.At the same time,it is pointed out that the novel not only reveals the life of Puritans,but also prompts readers to think about how to redeem themselves in the case of inherently evil human nature and explore the dark side of human nature and the deep themes of the novel against the dark and mysterious background.

Spatiotemporal Evolution of Ecological Quality in Alpine Freshwater Lake Nature Reserves in the Past 20 Years

The Caohai Nature Reserve is one of the three major plateau freshwater lakes in China.Since the 1950s,human activities such as land reclamation and population relocation have greatly damaged Caohai.A rapid evaluation of the spatiotemporal evolution trend of the ecological quality of the Caohai Nature Reserve is significant for the maintenance and construction of the ecosystem in this area.The research is based on the Google Earth Engine(GEE)remote sensing cloud computing platform.Landsat TM/OLI images from May to October in five time periods:2000-2002,2004-2006,2009-2011,2014-2016,and 2019-2021 were obtained to reconstruct the optimal cloud image set by averaging the images in each time period.By constructing four ecological indicators:Greenness(NDVI),Wetness(Wet),Hotness(LST),and Dryness(NDBSI),and using Principal Component Analysis(PCA)method to obtain the Remote Sensing Ecological Index(RSEI)for the corresponding years,the spatiotemporal variation of ecological quality in the Caohai Nature Reserve over 20 years was analyzed.The results indicate:①the mean value of RSEI increased from 0.460 in 2000-2002 to 0.772 in 2019-2021,a 67.83%increase,indicating a significant improvement in the ecological quality of the reserve over the 20 years;②from the perspective of functional zoning of the Caohai Nature Reserve,the ecological quality of the core area showed a degrading trend,while the ecological quality of the buffer zone and experimental zone significantly improved;③with the implementation of ecological restoration projects,the ecological quality of the reserve gradually recovered and improved from 2014 to 2021.The trend of RSEI value changes is well correlated with human interventions,indicating that the PCA-based RSEI model can be effectively used for ecological quality assessment in lake areas.

Nature’s Gift

NATURAL WONDERS IN CHINA AND AFRICA Qilian Mountains National Park Located in Northwest China’s Gansu and Qinghai provinces,Qilian Mountains National Park spans 50,200 square km,serving as a vital ecological security barrier and water source conservation area in west China.Established in 2017 to address ecosystem damage,intensive food chain protection and wildlife monitoring in the area began in early 2011.

“Eternal Motion” as a “Form of Movement of a Special Nature” and the Main Condition for the Creation of the Universe

The article hypothesizes that DE and DM (UCM) are a “Form of Motion of a Special Nature”, where “Form of Motion” means “Eternal Motion” as the power of dynamics of different levels and varying degrees of self-sufficiency, and by “Special Nature”, gravitational and two other properties of matter, “tied” to the “Eternal Movement” and completely dependent on it. Carriers of key properties of a “Special Nature” have been established: “0”-DE particles and “3”-DM particles (UDM). The unity of their inherent “motionally-gravitational” properties and the peculiarity of the relationship between “motion” and “gravity” are revealed: the higher the intensity of “Eternal Motion”, the stronger the gravitational properties of matter are manifested (and vice versa). The relationship of “time” with the “vibration frequency” and the “mass” of photons with the “degree of bonding and deformation properties of the field” is shown. The maximum level of gravity has been determined, which allows Nature to successfully create the Universe: such a landmark is the proximity to the property of the Primary Source—the “pure graviton” of the OSP space, the most powerful “motionally-gravitational” particle of the Universe. The reasons for the emergence of such an identity of the gravitational properties of particles with the indicators of a “pure graviton” are established: for “0”-DE particles, this is the acquisition of the function of “freedom of movement”;for “3”-DM particles (UDM), the creation of a special structure—a “double field” (“Main” and “Small”). The presence in the “double field” of specific “tools” for the creation of the worlds of the Universe—gravitational “waves” gives rise to impulses (shocks) of varying intensity and shape. A list of functions performed by “waves” in the “Main” and “Small” fields has been compiled. The specific conditions for the formation of “UDM Streams”, their transformation into a “Vortex” and, under the influence of a powerful Initial Impulse (push), sending them to the “place” of the creation of galaxies, are shown. It is suggested that there is a “Cycle of Matter in Nature” in the closed structure of our Universe due to the “work” of “waves” and the functioning of special “factories” in the form of exotic space objects—Black holes.

Formation, distribution, and nature of Picea mongolica in China

Picea mongolica is an endemic and endangered species in China. Ecosystem made of Picea mongolica is a special sandy forest ecosystem in China. It is found at ecotone between forest and steppe, or agricultural district and pastoral area. Based on investigation, this paper discussed the formation and distribution of Picea mongolica and studied its nature according to ecotone theory. It is clarified that Picea mongolica belongs to Picea meyeri series. That is to say, it became a local race through long-term adaptation to the local climate, then formed allopatric semi-species, and finally turned into a taxonomical species. Picea mongolica forest is a super zonal climax community developing in ecotone between forest zone and steppe zone.

Population Density and Habitat Utilization of Ibex(Capra ibex)in Tomur National Nature Reserve,Xinjiang,China

Surveys was conducted to study the population density and habitat utilization of the ibex （Capra ibex） in Tomur National Nature Reserve during October- December 2005. The results are as follows： ① The mean group size of the ibex in Tomur Nature Reserve is 8.43 and the population density is 269.76/100 km^2; ② The ibex prefer areas with steep slope （between 30° -45°）, broken substrates and cliffs nearby （ 〈 100 m）. They avoid grasslands and fiat hillsides; ③The probable reason for this habitat selection is serf-protection.

国际顶级学术期刊《Nature》的发展轨迹及启示

国际顶级学术期刊《Nature》146年的发展轨迹,诠释了学术期刊厚积薄发的发展规律。持之以恒和与时俱进是《Nature》宝贵而优秀的基因。文章以定性和定量的方式,从文献计量学的视角、人文的视角和国际化的视角三个层面分析和研究《Nature》的发展轨迹,并与我国一流学术期刊《科学通报》进行对比分析,在此基础上提出了一些针对我国学术期刊发展的启示和建议。

从近年PNAS,Nature,Science发表的涉及地衣的文章看地衣学进展

通过分析近10年在PNAS,Nature及Science上发表的涉及地衣的文章,并结合相关文献,总结了当前地衣学研究的主要方面及重要进展。对地衣化石、共生进化、系统发育、共生藻、功能遗传学、地衣生殖及生态生理学等领域取得的成果进行了概述,同时展望了中国地衣学研究的发展前景。