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瑞典沿海生境生态系统的物产与服务:生态系统变迁的鉴别、评估和意义

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AMBIO－人类环境杂志 2007年第B11期36卷 504-513页

作者： patrik rnnbck Nils Kautsky Leif Pihl Max Troell Tore Sderqvist Hkan Wennhage 梁虹瑞典Enveco顾问公司

人口高密度和经济快速发展使沿海地区处于多种威胁之中。这种状况如何影响人类福利及人类对生态系统物产与服务的依赖呢?本文首次对温带地区沿海主要生境(大型海藻、海草、翡翠贻贝床和无植被软海底)的生态系统物产与服务状况进行了评... 详细信息

人口高密度和经济快速发展使沿海地区处于多种威胁之中。这种状况如何影响人类福利及人类对生态系统物产与服务的依赖呢?本文首次对温带地区沿海主要生境(大型海藻、海草、翡翠贻贝床和无植被软海底)的生态系统物产与服务状况进行了评估。作者将40多种物产和服务细分为供给服务、调节服务和文化服务。作者列举了各类中瑞典境内各种生态系统服务的实例,包括经济价值和不同生境相对重要性评估。例如,具有极大重要性的翡翠贻贝对缓解富营养化的作用、沙质海滩的休闲娱乐功能、海草和大型藻类对渔产、波浪能和海流能的作用。本文评估了3种沿海生态系统变化对生态系统物产与服务的影响:1)海草床变为无植被海底;2)无植被浅水软海底向丝状藻类基质转变;3)坚硬基质上大型藻类向贻贝的转变。文章结尾部分对生物多样性评估、生态系统的普遍联系性和潜在经济价值等从管理角度进行了讨论。

关键词：生态系统服务沿海地区评估生境瑞典潜在经济价值鉴别变迁

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西印度洋地区海草生态系统

AMBIO－人类环境杂志 2002年第7期31卷 588-596页

作者： Martin Gullstrm Maricela de la Torre Castro Salomo O.Bandeira Mats Bjrk Mattis Dahlberg Nils Kautsky patrik rnnbck Marcus C.hman 章任群哥德堡大学海洋生态学系瑞典斯德哥尔摩大学系统生态学系爱德华多.蒙德莱恩大学生物科学系斯德哥尔摩大学植物学系瑞士哥德堡大学瑞典斯德哥尔摩大学瑞典斯德哥尔摩大学动物学系

海草是海洋被子植物,广泛分布在温带和热带的海岸带水域,是地球上水生生态系统中最具生产力的生物之一。在西印度洋地区大概有13种海草,这些海草覆盖了12000kg海岸线的近岸柔软海底广大区域。海草床一般分布在潮间带和潮下带,有时向下... 详细信息

海草是海洋被子植物,广泛分布在温带和热带的海岸带水域,是地球上水生生态系统中最具生产力的生物之一。在西印度洋地区大概有13种海草,这些海草覆盖了12000kg海岸线的近岸柔软海底广大区域。海草床一般分布在潮间带和潮下带,有时向下延伸至40m,并经常出现在珊瑚礁和红树林附近。由于具有很高的初级生产力和复杂的栖息环境,海草供养了许多底栖生物和浮游生物。许多鱼类和贝类,包括那些具有商业价值的种类都被吸引到海草栖息地,将海草作为其食物来源和避难场所,特别是在它们的幼年期。分布在西印度洋海草床附近广泛而丰富的鱼类资源就足以说明这一点。这些鱼分别属于天竺鲷科、亚科、玻甲鱼科、银鲈科、虾虎鱼科、隆头鱼科、裸颊鲷科、笛鲷科、单角亚科、鹦嘴鱼科、科、篮子鱼科、海龙科和Teraponidae科。因此,西印度洋地区的海草生态系统无论对当地还是整个地区的渔业发展都是非常有价值的资源。尽管如此,与其他地区相比,该地区有关海草资源的研究还十分缺乏,而且大多数研究也都集中在植物多样性和生态学上。本文主要阐述西印度洋地区海草床研究现状,特别强调鱼类和渔业。目前,该课题的大多数研究主要是在东非海岸开展的,如肯尼亚,坦桑尼亚,莫桑比克以及南非东部地区,而在索马里和西印度洋地区的岛屿国家(塞舌尔、科摩罗、法属留尼旺岛、毛里求斯、马达加斯加等)此类研究却很少,有关海草鱼类生态系统的论文也少有发表,而且大部分都是描述性的。因此,需要通过研究和实验获得有关描述模式和处理方法的科学知识。关于海草鱼类群落的定量研究,类似本文所介绍的案例研究在西印度洋地区是很少的,而这些研究对于渔业的管理前景而言是必不可少的。值得强调的是由于海岸人口的不断增长以及人类活动的侵扰给该地区海草床带来的压力与日俱增,如污染,海水富营养化,沉积作用,捕鱼以及无脊椎动物的采集等活动,而这些活动对于海草床的影响却鲜为人知。因此,需要开展广泛的研究,为西印度洋地区海草生态系统可持续管理提供有用的信息服务。

关键词：西印度洋地区海草生态系统海草分布生态学栖息地生长繁殖

Microbiological Quality of “rabilé”, a Yeast Used for Fermentation of Dolo, a Local Beer in Dédougou, Burkina Faso

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Open Journal of Applied Sciences 2024年第4期14卷 849-864页

作者： Amana Metuor Dabiré Nicolas Ouédraogo Cheick Alassane Djibila Damis Yves patrik Bouniounou Molecular Biology and Genetics Laboratory (LABIOGENE) Universit&#233 Joseph Ki-Zerbo Ouagadougou Burkina Faso Training and research Unit in Applied Sciences and Technologies Department of Biochemistry Microbiology University of Dedougou Dedougou Burkina Faso National Center for research and Training on Malaria (CNrFP) Ouagadougou Burkina Faso

Sorghum beer or dolo is part of the eating habits of part of the population of Dédougou because of its low price compared with industrial beers. Its production is an ancestral tradition that uses traditional equipment and gives dolo organoleptic properties that are not found in industrial beers. The production process involves several stages, including fermentation, which itself comprises natural lactic fermentation followed by alcoholic fermentation using traditional yeasts, which are not controlled in any way. The general aim of this study is to assess the microbiological quality of these fermentative yeasts in the town of Dédougou, in order to contribute to the health safety of the population and the promotion of these local beers. Twenty samples of fermenting yeast were analyzed according to ISO standards, to isolate enterobacteria, total and faecal coliforms according to standard procedures for isolating these micro-organisms. The isolated strains were identified using the API20E gallery. Microbiological analyses revealed the presence of 51.17% enterobacteria, 45.38% total coliforms and 3.45% thermotolerant coliforms. We counted 40% Escherichia coli, 20% Enterobacter cloacae, 20% Klebsiella pneumoniae and 20% Klebsiella spp. All the strains detected are capable of surviving in hostile conditions and could harm the quality of the dolo, consumer health and cause real collective food poisoning in the town of Dédougou. This enabled us to assess the microbial quality of these yeasts and to propose more suitable measures for producing and preserving dolo under hygienic conditions to protect consumer health.

关键词： Dolo Yeast rabilé Microbiological Quality Bacteria

Frontal Sinus Fractures: Management at the Yalgado Ouedraogo University Hospital Centre (Burkina Faso)

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Open Journal of Stomatology 2024年第1期14卷 42-54页

作者： Arsène Coulibaly patrik Gane-Bang Joseph Wend-Toin Biogo Ibraïma Traoré Tarcissus Konsem Department of Maxillofacial Surgery Regional University Hospital Centre of Ouahigouya Ouahigouya Burkina Faso Department of Stomatology and Maxillofacial Surgery Regional Hospital Centre of Banfora Banfora Burkina Faso Department of Neurosurgery Regional University Hospital Centre of Ouahigouya Ouahigouya Burkina Faso Department of Stomatology and Maxillofacial Surgery Souro SANOU University Hospital Centre Bobo Dioulasso Burkina Faso Department of Stomatology and Maxillofacial Surgery Yalgado OUEDRAOGO University Hospital Centre Ouagadougou Burkina Faso

Introduction: Frontal sinus fractures are potentially serious. They are defined as a solution of continuity, open or closed, of one or both bone tables of the frontal sinus. This study aims to report on the management of them at the Yalgado OUEDrAOGO University Hospital Centre. Methodology: It is a descriptive cross-sectional study with retrospective collection from January 01, 2016 to December 31, 2018. Patients with frontal sinus fractures were managed at the Yalgado OUEDrAOGO University Hospital Centre through CT-scan proof. results: Over three years, a total of 102 cases of frontal sinus fractures were collected with 29.9 years as average age. There were 96 men. Workers in the informal sector and pupils/students represented 58.90% of patients. The residence of the patients was urban in 68.80% of cases and rural in 31.40%. road traffic accidents (rTAs) happened in 90.20%, and involved 2-wheelers in 98.20%. None of these drivers was wearing a helmet. The type III frontal fracture of Ioannides et al. represented 51.9% of cases. In 89.21% of cases, other facial and/or cranioencephalic injuries were compounded to frontal sinus fractures. No surgical management was observed in 82 (80.39%) patients and surgical management in 20 (19.61%) patients. The outcome was favourable, but sequelae and/or complications were noted in 10 patients who had surgery and 30 patients who did not. Conclusion: These results enforce helmet wearing for all riders of two-wheeled machines. In addition, vaccinations to prevent meningitis in frontal sinus fractures with dural breach should be systematic.

关键词： Management Frontal Sinus Fracture Burkina Faso

Why ecosystem characteristics predicted from remotely sensed data are unbiased and biased at the same time-and how this affects applications

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Forest Ecosystems 2024年第1期11卷 24-31页

作者： Goran Ståhl Terje Gobakken Svetlana Saarela Henrik J.Persson Magnus Ekstrom Sean P.Healey Zhiqiang Yang Johan Holmgren Eva Lindberg Kenneth Nystrom Emanuele Papucci patrik Ulvdal Hans OleØrka Erik Næsset Zhengyang Hou Håkan Olsson ronald E.Mcroberts Department of Forest resource Management Swedish University of Agricultural Sciences90183UmeåSweden Faculty of Environmental Sciences and Natural resource Management Norwegian University of Life SciencesÅsNorway USDA Forest Service Rocky Mountain Research StationOgdenUTUSA The Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing100083China Department of Forest resources University of MinnesotaSt.PaulMNUSA

remotely sensed data are frequently used for predicting and mapping ecosystem characteristics,and spatially explicit wall-to-wall information is sometimes proposed as the best possible source of information for ***,wall-to-wall information typically relies on model-based prediction,and several features of model-based prediction should be understood before extensively relying on this type of *** such feature is that model-based predictors can be considered both unbiased and biased at the same time,which has important implications in several areas of *** this discussion paper,we first describe the conventional model-unbiasedness paradigm that underpins most prediction techniques using remotely sensed(or other)auxiliary *** this point of view,model-based predictors are typically ***,we show that for specific domains,identified based on their true values,the same model-based predictors can be considered biased,and sometimes severely *** suggest distinguishing between conventional model-bias,defined in the statistical literature as the difference between the expected value of a predictor and the expected value of the quantity being predicted,and design-bias of model-based estimators,defined as the difference between the expected value of a model-based estimator and the true value of the quantity being *** show that model-based estimators(or predictors)are typically design-biased,and that there is a trend in the design-bias from overestimating small true values to underestimating large true ***,we give examples of applications where this is important to acknowledge and to potentially make adjustments to correct for the design-bias *** argue that relying entirely on conventional model-unbiasedness may lead to mistakes in several areas of application that use predictions from remotely sensed data.

关键词： Bias Model-based inference Design-based inference

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成都科幻馆

建筑实践 2024年第4期 40-43页

作者： patrik Schumacher 桥谕 Paulo Flores 扎哈·哈迪德建筑事务所

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Deformation,fragmentation and acceleration of a controlled fragmentation charge casing

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Defence Technology（防务技术） 2019年第5期15卷 786-795页

作者： Andreas Helte Olof Andersson patrik Lundberg FOI Defence and SecuritySystems and Technology

Two different finite element software,LS-DYNA and Impetus,have been evaluated to test their ability to predict the deformation,fragmentation and acceleration of a controlled fragmentation charge *** general-purpose program LS-DYNA was used with a multi-material ALE formulation and a masspreserving erosion criterion coupled to a Johnson-Cook fracture *** the Impetus simulations,a third order Lagrangian element formulation was used for the casing and a node-splitting element erosion treatment coupled to a Cockcroft-Latham failure criterion was used to describe casing *** high-explosive gases were described by a discrete particle *** order to acquire data to validate our computational tools and constitutive models,a series of experiments have been performed using a laboratory charge with an internal grooved *** the test series,the charge geometry was fixed except that the groove depth were varied from very shallow to very deep resulting in different deformation patterns,fracture modes and terminal *** diagnostic tools captured the different stages of the expansion and fragmentation of the casing.A high-speed framing camera depicted the deformation pattern before fragmentation and was used to determine the moment when the casing *** different complementary techniques were used to follow the acceleration of the fragments;a Photon Doppler velocimetry to determine the initial acceleration of the casing,double exposed radiographs to estimate the fragment velocity after break-up and a high-speed video to determine the terminal velocity of the fragment after leaving the *** addition,the fragments were soft recovered in a set of sawdust pit tests and their final shape and weight were measured.A SEM was used to characterise the fracture surfaces and to determine the modus of fracture(tensile or shear failure).Comparisons to experiments show that both software can predict the change in deformation behaviour

关键词： Controlled fragmentation Fracture mechanics LS-DYNA Impetus

A novel feature extraction methodology using Siamese convolutional neural networks for intrusion detection

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Cybersecurity 2018年第1期1卷 847-859页

作者： Serafeim Moustakidis patrik Karlsson AIDEAS OU Narva mnt 5TallinnHarju maakondEstonia

Intrusion detection systems(IDS)can play a significant role in detecting security threats or malicious attacks that aim to steal information and/or corrupt network *** deal with the dynamic and complex nature of cyber-attacks,advanced intelligent tools have been applied resulting into powerful and automated IDS that rely on the latest advances of machine learning(ML)and deep learning(DL).Most of the reported effort has been devoted on building complex ML/DL architectures adopting a brute force approach towards the maximization of their detection ***,just a limited number of studies have focused on the identification or extraction of user-friendly risk indicators that could be easily used by security *** papers have explored various dimensionality reduction algorithms,however a large number of selected features is still required to detect the attacks successfully,which humans cannot intuitively or immediately *** enhance user’s trust and understanding on data without sacrificing on accuracy,this paper contributes to the transformation of the available data collected by IDS into a single actionable and easy-to-understand risk *** achieve this,a novel feature extraction pipeline was implemented consisting of the following components:(i)a fuzzy allocation scheme that transforms raw data to fuzzy class memberships,(ii)a novel modality transformation mechanism for converting feature vectors to images(Vec2im)and(iii)a dimensionality reduction module that makes use of Siamese convolutional neural networks that finally reduces the input data dimensionality into a 1-d feature *** performance of the proposed methodology was validated with respect to detection accuracy,dimensionality reduction performance and execution time on the NSL-KDD dataset via a thorough comparative analysis that demonstrated its effectiveness(86.64%testing accuracy using only one feature)over a number of well-known feature selection(FS)and extracti

关键词： Feature extraction Siamese convolutional neural networks Machine learning Intrusion detection

Influence of confining prestress on the transition from interface defeat topenetration in ceramic targets

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Defence Technology（防务技术） 2016年第3期12卷 263-271页

作者： patrik LUNDBErG renérENSTrOM Olof ANDErSSON FOI Swedish Defence Research AgencySE-164 90 StockholmSweden

replica scaled impact experiments with unconfined ceramic targets have shown that the transition velocity,i.e.,the impact velocity at which interface defeat ceases and ceramic penetration occurs,decreased as the length scale increased.A possible explanation of how this scale effect is related to the formation of a cone crack in the ceramic has been presented by the authors in an earlier ***,the influence of confinement and prestress on cone cracking and transition velocity is *** hypothesis is that prestress will suppress the formation and growth of the cone crack by lowering the driving stress.A set of impact experiments has been performed in which the transition velocity for four different levels of prestress has been *** transition velocities as a function of the level of confining prestress is compared to an analytical model for the influence of prestress on the formation and extension of the cone crack in the ceramic *** experiments and model indicate that prestress has a strong influence on the transition from interface defeat to penetration,although the model underestimates the influence of prestress.

关键词： Impact Ceramic Armour Interface defeat Dwell Confinement Prestress