230 research outputs found
Künstliche Nisthilfen für Wildbienen in der Stadt Zürich : eine Evaluation der verwendeten Materialien und Lösungen
Die Population der Wildbienen umfasst in der Schweiz ebenso wie im sonstigen Zentraleuropa eine Reihe von stark gefährdeten Arten. Diese Gefährdung hat viele Ursachen, die teilweise menschengemacht sind. Dazu zählen die Verknappung des Nahrungsangebots sowie die Verringerung der Nistmöglichkeiten. Deshalb liegt es auch am Menschen, Lösungen zu finden, die den Wildbienenarten das Überleben erleichtern. Eine dieser Möglichkeiten liegt in der Einrichtung künstlicher Nisthilfen. Diese Nisthilfen aus unterschiedlichen, meist natürlichen Materialien bieten Unterschlupf und Brutmöglichkeiten. Doch nicht alle Materialien, die verwendet werden, sind auch wirklich tauglich. In der folgenden Arbeit soll zunächst gezeigt werden, welche Produkte käuflich zu erwerben sind und welche davon empfohlen werden können. Dann erfolgt die Auseinandersetzung mit den geeigneten Materialien im Einzelnen. Am Ende wird eine erste Bestandsaufnahme der in Zürich zu findenden künstlichen Nisthilfen statistisch ausgewertet.The population of wild bees in Switzerland as well as in other central European countries includes a number of highly endangered species. This threat has many causes, some of which are man-made. These include a diminished supply of food as well as a reduction of the possibilities for nesting. Therefore, it is up to humans to find solutions that help the wild bee species to survive. One of these possibilities is the establishment of artificial nesting aids. These nesting aids contain various, mostly natural materials and provide shelter and breeding opportunities. However, not all materials that are used are really suitable. The following work will show which products are available for purchase and which ones can be recommended. At the end a first stocktaking of the nesting aids to be found in Zurich is statistically evaluated
Accelerated forgetting of a trauma-like event in healthy men and women after a single dose of hydrocortisone
Posttraumatic stress disorder (PTSD) is characterised by dysregulated hypothalamic-pituitary-adrenal axis activity and altered glucocorticoid receptor sensitivity. Early treatment with glucocorticoids may reduce PTSD risk, although the effect of such treatment on the aetiologically critical step of traumatic-memory-formation remains unclear. Here we examine the effects of exogenous cortisol (hydrocortisone) in a preclinical model of PTSD, using a factorial (Drug × Sex), randomised-controlled, double-blind design. Healthy men and women (n = 120) were randomised to receive 30 mg oral hydrocortisone or matched placebo immediately after watching a stressful film. Effects on film-related intrusions were assessed acutely in the lab, and ecologically using daily memory diaries for one week. We found that participants receiving hydrocortisone showed a faster reduction in daily intrusion frequency. Voluntary memory was assessed once, at the end of the week, but was unaffected by hydrocortisone. Exploratory analyses indicated sex-dependent associations between intrusions and baseline estradiol and progesterone levels. In men receiving hydrocortisone, higher baseline estradiol levels were associated with fewer intrusions, whereas women exhibited the opposite pattern. By contrast, progesterone levels were positively associated with intrusions only in men treated with hydrocortisone. The findings suggest that hydrocortisone promotes an accelerated degradation of sensory-perceptual representations underlying traumatic intrusive memories. In addition, while sex alone was not an important moderator, the combination of sex and sex-hormone levels (especially estradiol) influenced hydrocortisone’s effects on involuntary aversive memories. Future well-powered experimental studies may provide a basis for a precision-psychiatry approach to optimising early post-traumatic glucocorticoid treatments that target intrusive memories, based on individual endocrinological profiles
MAURICE MARTEL et PAUL MARTEL, La compagnie au Québec. Les aspects juridiques, Montréal, Wilson & Lafleur Ltée/Martel Ltée, 1989, 1019 p., ISBN 2-920831-06-2. Deuxième édition, 1990, 1021 p., ISBN 2-920831-20-8.
The seasonal variation of the protozooplanktonic community (ciliates and testate amoebae) was studied in a tropical oligotrophic reservoir in Brazil, which was under the influence of two contrasting climatic seasons (rainy/warm and dry/cold). The aim of this study was to evaluate the effect of these climatic changes on physical, chemical and biological variables in the dynamic of this community. The highest mean density of total protozoans occurred in the rainy/warm season (5683.2 ind L-1), while the lowest was in the dry/cold (2016.0 ind L-1). Considering the seasonal variations, the protozoan groups that are truly planktonic, such as the oligotrichs (Spirotrichea), predominated in the dry season, whereas during the rainy season, due to the material input and resuspension of sediment, sessile protozoans of the Peritrichia group were the most important ones. The dominant protozoans were Urotricha globosa, Cothurnia annulata, Pseudodifflugia sp. and Halteria grandinella. The highest densities of H. grandinella were associated with more oxygenated and transparent water conditions, while the highest densities of C. annulata occurred in sites with high turbidity, pH and trophic state index (TSI). The study demonstrated that density and composition of protozooplanktonic species and groups of the reservoir suffered seasonal variation due to the environmental variables (mainly temperature, turbidity, water transparency, dissolved oxygen and TSI) and the biological variables (e.g. morphological characteristics, eating habits and escape strategies from predation of the species).Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Aspectos epidemiológicos da Leishmaniose Tegumentar Americana no município de Juína, Mato Grosso, Brasil = Epidemiological aspects of American Cutaneous Leishmaniasis in the city of Juína, Mato Grosso state, Brazil
Objetivos: o objetivo deste trabalho foi estudar possíveis consequências da ação antrópica nas regiões urbana e rural do Município de Juína, estado de Mato Grosso, descrever aspectos epidemiológicos da Leishmaniose Tegumentar Americana e investigar a relação desta doença com atividades ocupacionais. Métodos: foram analisadas as notificações de Leishmaniose Tegumentar Americana no Município no período entre 2004 e 2006, fornecidas pela Secretaria Municipal de Saúde. Resultados: observou-se que entre os 458 casos notificados de Leishmaniose Tegumentar Americana foi maior a proporção de indivíduos do sexo masculino (89,10% dos casos), da faixa etária entre 20 a 39 anos (49,10%) e de atividades ocupacionais voltadas para a agropecuária e para o garimpo (62,90%). Ao analisar o possível local da fonte de infecção observou-se que a grande maioria dos indivíduos infectados esteve em contato com a zona rural (95,40%). Em relação ao tipo de lesão, observou-se predomínio das lesões do tipo cutâneo (94,10%). Conclusões: a análise dos dados revelou que a Leishmaniose Tegumentar Americana é uma parasitose importante no município de Juína. Os dados sugerem relação com a atividade laboral e um perfil de transmissão predominantemente silvestre, o que deve ser levado em conta ao definir medidas de controle da doença na regiã
Editorial: The role of adipose tissue and resident immune cells in infections
Adipose tissues are distributed throughout the body and are in direct contact with sites of infection entry, such as mucosal tissues, gut, and skin. There is increasing appreciation that adipose tissue can influence local and systemic immune responses to infection. The adipose tissue can modulate immune responses through changes in the expression of pro- and anti-inflammatory cytokines, adipokines, and hormones that regulate general metabolism. Immune cells within adipose show differentiation states that are distinct from those in circulation or in lymphoid tissues, suggesting that the adipose environment regulates immune cell activity. The mechanisms leading to immune cell recruitment and maintenance within adipose remain enigmatic. Changes in diet that lead to obesity can alter the frequencies of regulatory or effector cells within adipose, potentially affecting local and systemic immune protection. Obesity is associated with higher susceptibility to infections possibly due to alterations in immune cells residing in adipose tissue. The interplay between immune cells and adipose is complex and bi-directional: immune cells residing within adipose tissue can perturb adipose tissue homeostasis and whole-body metabolism and, conversely, metabolic cues can modulate immune responses. Several reports demonstrate that microorganisms can target and even persist in adipose tissues. However, relatively few studies have addressed the immunological consequences of adipose tissue infection
In situ monitoring and mechanism of the mechanochemical formation of a microporous MOF-74 framework
Mechanochemistry provides a rapid, efficient route to metal-organic framework Zn-MOF-74 directly from a metal oxide and without bulk solvent. In situ synchrotron X-ray diffraction monitoring of the reaction course reveals two new phases and an unusual step-wise process in which a close-packed intermediate reacts to form the open framework. The reaction can be performed on a gram scale to yield a highly porous material after activation
Antibodies to Cryptic Epitopes in Distant Homologues Underpin a Mechanism of Heterologous Immunity between <i>Plasmodium vivax</i> PvDBP and <i>Plasmodium falciparum</i> VAR2CSA
Rational Synthesis of Mixed-Metal Microporous Metal–Organic Frameworks with Controlled Composition Using Mechanochemistry
Mechanochemistry enables targeted, rapid synthesis of bimetallic metal−organic frameworks (MOFs) with a controlled 1:1 stoichiometric composition of metal nodes. In particular, ball milling enabled the use of specifically synthesized solid coordination complexes of Zn(II), Mg(II), Ni(II), and Co(II) for the assembly of a range of microporous mixed-metal MOF-74 materials composed of pairs of d-block or main group metals in a predetermined 1:1 stoichiometric ratio, including ZnMg-, ZnCo-, ZnCu-, MgZn-, MgCo-, NiZn-, NiMg-, NiCo-, CoZn-, CoMg-, CoCu-, and MgCa-MOF-74. By using specifically prepared precursors in the ynthesis of diverse mixed-metal MOF-74 targets, this rational synthesis represents the first entry of mechanochemistry into the target-oriented synthesis of mixed- metal MOFs
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