Nutzung von MPI für parallele FEM-Systeme

Der Standard des Message Passing Interfaces (MPI) stellt dem Entwickler paralleler Anwendungen ein mächtiges Werkzeug zur Verfügung, seine Softwa- re effizient und weitgehend unabhängig von Details des parallelen Systems zu entwerfen. Im Rahmen einer Projektarbeit erfolgte die Umstellung der Kommunikationsbibliothek eines bestehenden FEM-Programmes auf den MPI-Mechanismus. Die Ergebnisse werden in der hier gegebenen Beschreibung der Cubecom-Implementierung zusammengefasst. In einem zweiten Teil dieser Arbeit wird untersucht, auf welchem Wege mit der in MPI verfügbaren Funktionalität auch die Koppelrandkommunikation mit einem einheitlichen und effizienten Verfahren durchgeführt werden kann. Sowohl fuer die Basisimplementierung als auch die MPI-basierte Koppelrandkommunikation wird die Effizienz untersucht und ein Ausblick auf weitere Anwendungsmoeglichkeiten gegeben

Demographic factors associated with insecticide treated net use among Nigerian women and children

Background: Malaria constitutes a major health problem, with children and pregnant women being the most vulnerable to its morbidity and mortality. Aim: To determine the demographic factors associated with the use of insecticide-treated nets among children and pregnant women in Nigeria. Materials and Methods: The study was based on data drawn from the Nigeria Demographic and Health Survey 2008 on the use of insecticide-treated nets among women and children. The survey was conducted in 34070 households and a total of 10,724 women aged 15-49 years participated in the survey. Data were entered into Minitab version 15 and the chi-square test for independence was performed to show association between variables. Results: The results revealed that 49.8% of children and 44% of pregnant women present in households that owe insecticide-treated nets slept under them on the night before the survey. Sleeping under an insecticide-treated nets among children was associated with (P<0.05) the age of a child, geopolitical zone, and wealth quintile while the use of insecticide-treated nets among pregnant women was associated with the education level and wealth quintile of households. Conclusion: The study demonstrated that some demographic factors are associated with the use of ITNs among children and pregnant women in Nigeri

Analysing and Recommending Options for Maintaining Universal Coverage with Long-Lasting Insecticidal Nets: The Case of Tanzania in 2011.

Tanzania achieved universal coverage with long-lasting insecticidal nets (LLINs) in October 2011, after three years of free mass net distribution campaigns and is now faced with the challenge of maintaining high coverage as nets wear out and the population grows. A process of exploring options for a continuous or "Keep-Up" distribution system was initiated in early 2011. This paper presents for the first time a comprehensive national process to review the major considerations, findings and recommendations for the implementation of a new strategy. Stakeholder meetings and site visits were conducted in five locations in Tanzania to garner stakeholder input on the proposed distribution systems. Coverage levels for LLINs and their decline over time were modelled using NetCALC software, taking realistic net decay rates, current demographic profiles and other relevant parameters into consideration. Costs of the different distribution systems were estimated using local data. LLIN delivery was considered via mass campaigns, Antenatal Care-Expanded Programme on Immunization (ANC/EPI), community-based distribution, schools, the commercial sector and different combinations of the above. Most approaches appeared unlikely to maintain universal coverage when used alone. Mass campaigns, even when combined with a continuation of the Tanzania National Voucher Scheme (TNVS), would produce large temporal fluctuations in coverage levels; over 10 years this strategy would require 63.3 million LLINs and a total cost of $444 million USD. Community mechanisms, while able to deliver the required numbers of LLINs, would require a massive scale-up in monitoring, evaluation and supervision systems to ensure accurate application of identification criteria at the community level. School-based approaches combined with the existing TNVS would reach most Tanzanian households and deliver 65.4 million LLINs over 10 years at a total cost of$449 million USD and ensure continuous coverage. The cost of each strategy was largely driven by the number of LLINs delivered. The most cost-efficient strategy to maintain universal coverage is one that best optimizes the numbers of LLINs needed over time. A school-based approach using vouchers targeting all students in Standards 1, 3, 5, 7 and Forms 1 and 2 in combination with the TNVS appears to meet best the criteria of effectiveness, equity and efficiency

Information and Interaction Needs of Distance Students: Are Academic Libraries Meeting the Challenge?

One of the trends currently affecting academic libraries is higher education’s expanding use of online instruction and a rising number of totally online degree programs. As libraries have transitioned from primarily print holdings to a growing reliance on electronic formats, access has become more convenient for all, including distance students. However, the greater availability of e-resources can create a disconnect between the materials used by students and the institution that provides those resources, as well as the librarians who serve as instructors and guides. Libraries have struggled to close the gap by reinventing themselves as a ‘third place’ which students visit for study, assistance, collaboration, and socialization but are challenged with how to establish an identity and a presence with virtual students who are unable to utilize the physical library as a ‘third place’. This paper examines recent literature to understand what practices academic libraries are implementing in order to meet the needs of distance students.Publishe

VENOM COMPOSITION OF LITTLE KNOWN MOUNTAIN RATTLESNAKES AND PREDATOR-PREY INTERACTIONS OF CROTALUS PRICEI PRICEI AND ITS NATURAL PREY, SCELOPORUS JARROVII

The Crotalus intermedius clade is a small group composed of four species: C. intermedius, C. transversus, C. pricei, and the recently identified C. tancitarensis (Alvarado-Díaz and Campbell, 2004; Reyes-Valesco et al. 2013). Though these species are restricted to high elevations of Sky Islands of southern Arizona and throughout México, little has been reported about their natural history and basic biology, including venom composition. Specifically, the Western Twin-spotted Rattlesnake (C. pricei pricei) is a small lizard specialist restricted to the more northern Sky Islands of México, with isolated populations in southern Arizona, where they are a protected species. Crotalus p. pricei is restricted to high elevations, dispersal between mountain tops is impossible, and few studies have investigated venom composition, the predator-prey relationship between C. p, pricei and its primary prey source, Yarrow’s Spiny Lizard (Sceloporus jarrovii), or ecological variables impacting distribution. This project aimed to characterize the venom of species within the Crotalus intermedius clade and the trophic and distributional relationships between S. jarrovii and C. p. pricei by using venom analysis techniques, lethal toxicity assays, and species distribution modeling techniques. Reverse-phase high-performance liquid chromatography (RP-HPLC), gel electrophoresis, and several enzyme assays were used to identify compounds present in crude venom. Lethal toxicity assays were used to determine venom lethality towards Hemidactylus frenatus.(House Gecko) and S. jarrovii. Resource selection probability functions (RSPF) were evaluated to determine spatiotemporal ecological requirements of both C. p. pricei and S. jarrovii. The results of this study provides insight into the venom composition of little known, mountain rattlesnakes, the coevolutionary relationship between a lizard specialist (C. p. pricei) and its natural prey (S. jarrovii), and novel information on the likely distribution of both species based on ecological requirements. This information provides a solid basis for future land management and conservation plans concerning the unique habitats and fauna of the Sky Island ranges

Library instruction for students in speech-language pathology and audiology: Which databases should be covered?

Purpose: 1) To determine which databases are commonly recommended for students in speech-language pathology (SLP) and audiology programs 2) To compare journal indexing in those databases to decide which ones should be prioritized when teaching “one-shot” sessions. Methodology: Libguides of top-ranked audiology and SLP programs were examined to develop a list of recommended databases. Journal Citation Reports, SCImago Journal Rankings, and Google Scholar Top Publications were used to create a list of core journals in the subject area. Each of the identified databases was checked for indexing of core journals; the resulting spreadsheet was analyzed to determine which database or combination of databases offered the most complete coverage of core journals. Results: Six recommended databases and 34 core journals were identified. One journal was not indexed in any of the databases; no single database indexed all the remaining 33 titles. Web of Science included the most titles (28) but only if all sections (Science Citation Index, Science Citation Index Expanded and Social Sciences Citation Index) are available; PubMed/Medline was second with 26 titles. Indexing for 32 of 33 titles is available in two different database combinations, 1) PubMed/Medline and PsycINFO or 2) Web of Science (all sections) and Linguistics and Language Behavior Abstracts. Conclusion: A multi-session library instruction class might be able to cover the use of most or all of the six identified databases but many librarians are limited to one session with students and need to limit the number of new resources taught. This study found two database groupings which offer indexing for 32 of 33 core journals. Librarians can use information from this study together with institution-specific factors to decide which databases to prioritize in instruction sessions for SLP and audiology students

Introducing Faculty and Graduate Students to Systematic Reviews: Evaluation of a Stand-Alone Workshop

Objective: To discuss the development, perception, and impact of a stand-alone workshop intended to introduce faculty and graduate students to systematic review methodology. Methods: Development/revision of the workshop was examined through content analysis of lesson plans, PowerPoints, class examples and handouts. A short questionnaire was sent to participants within a few days of most workshops since 2018; all responses were analyzed to explore participant perceptions. Impact was assessed with an additional questionnaire sent in 2021 to all previous participants asking about progress and/or intentions to complete a systematic review. Results: Between 9/7/2018 and 5/27/2018, there were 29 responses to the post-workshop questionnaire. Over 75% of respondents strongly agreed that the workshop met their expectations and that what they learned would be helpful in other research and/or assignments. About 66% strongly agreed that they feel more capable of beginning a systematic review. Most frequently mentioned helpful aspects were the sample reviews provided and the Libraries’ subject guide/resources; challenges included too much information and understanding the differences between various types of reviews. There were also 24 responses to a recent questionnaire sent to all previous participants (n=221). Twenty-two respondents reported having completed or intending to complete a review; 20 having published or intending to publish a review; 7 having used or intending to use a review as part of a thesis, and 11 having used or intending to use a review as part of a dissertation. Twelve respondents also reported additional benefits of the workshop outside of completing/publishing a review. Conclusions: Positive responses to the questionnaire about workshop perceptions, the number of participants who report intentions to complete a systematic review, and the number of participants who report other benefits of the workshop suggest the workshop should continue to be offered

Covalency and ionicity do not oppose each other : relationship between Si-O bond character and basicity of siloxanes

Covalency and ionicity are orthogonal rather than antipodal concepts. We demonstrate for the case of siloxane systems [R3Si-(O-SiR2)(n)-O-SiR3] that both covalency and ionicity of the Si-O bonds impact on the basicity of the Si-O-Si linkage. The relationship between the siloxane basicity and the Si-O bond character has been under debate since previous studies have presented conflicting explanations. It has been shown with natural bond orbital methods that increased hyperconjugative interactions of LP(O)->sigma*(Si-R) type, that is, increased orbital overlap and hence covalency, are responsible for the low siloxane basicity at large Si-O-Si angles. On the other hand, increased ionicity towards larger Si-O-Si angles has been revealed with real-space bonding indicators. To resolve this ostensible contradiction, we perform a complementary bonding analysis, which combines orbital-space, real-space, and bond-index considerations. We analyze the isolated disiloxane molecule H3SiOSiH3 with varying Si-O-Si angles, and n-membered cyclic siloxane systems Si2H4O(CH2)(n-3). All methods from quite different realms show that both covalent and ionic interactions increase simultaneously towards larger Si-O-Si angles. In addition, we present highly accurate absolute hydrogen-bond interaction energies of the investigated siloxane molecules with water and silanol as donors. It is found that intermolecular hydrogen bonding is significant at small Si-O-Si angles and weakens as the Si-O-Si angle increases until no stable hydrogen-bond complexes are obtained beyond phi(SiOSi) = 168 degrees, angles typically displayed by minerals or polymers. The maximum hydrogen-bond interaction energy, which is obtained at an angle of 105 degrees, is 11.05 kJ mol(-1) for the siloxane-water complex and 18.40 kJ mol(-1) for the siloxane-silanol complex