993 resultados para 15-150


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采用分子束外延(MBE)技术,在GaSb(100)衬底上外延生长晶体结构完整和表面平整的Ⅱ型超晶格InAs(1.2 am)/GaSb(2.4 am).拉曼光谱表明:随着温度从70 K升高至室温,由于热膨胀作用和光声子散射过程中的衰减,超晶格纵光学声子拉曼频移向低波数方向移动5 cm~(-1),频移温度系数约为0.023 cm~(-1)/K.光致发光(PL)峰在2.4~2.8 μm,由带间辐射复合和束缚激子复合构成,2.55 μm PL峰随温度变化(15~150 K)发生微小红移,超晶格中InAs电子带与GaSb空穴带带间距随温度变化比体材料的禁带宽度小.PL发光强度在15~50 K随温度升高而升高,在60~150 K则相反,并在不同温度段表现出不同的温度依赖关系.

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本文对科尔沁沙地西部地区的小叶锦鸡儿群落进行了有关类型、生物量和复壮更新方面的研究。根据15块样地150个样方的数据,经排序处理,将本区小叶锦鸡儿群落划分为5个群丛,探讨了各群丛的特征。通过各龄级小叶锦鸡儿人工群落的试验观测,阐明了小叶锦鸡儿各龄级生物量季节性动态和年际动态。根据生物量动态的研究提出将小叶锦鸡儿整个生长发育期划分为幼年期和成年期。探讨了幼年期和成年期的各自特征。并根据各龄级平茬处理,前后生物量的特征提出了平茬能使小叶锦鸡儿恢复到幼年期依据,约第10年平茬小叶锦鸡儿当年生物量与未平茬的当年生物量相当。同时,提出了适于平茬复壮更新的平茬间隔时间。

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The dispersal capabilities of intertidal organisms may represent a key factor to their survival in the face of global warming, as species that cannot adapt to the various effects of climate change will have to migrate to track suitable habitat. Although species with pelagic larval phases might be expected to have a greater capacity for dispersal than those with benthic larvae, interspecies comparisons have shown that this is not always the case. Consequently, population genetic approaches are being increasingly used to gain insights into dispersal through studying patterns of gene flow. In the present study, we used nuclear single-nucleotide polymorphisms (SNPs) and mitochondrial DNA (mtDNA) sequencing to elucidate fine-scale patterns of genetic variation between populations of the Black Katy Chiton, Katharina tunicata, separated by 15-150 km in south-west Vancouver Island. Both the nuclear and mitochondrial data sets revealed no genetic differentiation between the populations studied, and an isolation-with-migration analysis indicated extensive local-scale gene flow, suggesting an absence of barriers to dispersal. Population demographic analysis also revealed long-term population stability through previous periods of climate change associated with the Pleistocene glaciations. Together, the findings of the present study suggest that this high potential for dispersal may allow K. tunicata to respond to current global warming by tracking suitable habitat, consistent with its long-term demographic stability through previous changes in the Earth's climate. (C) 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 106, 589597.

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The Preto River, located in the northwest of São Paulo State, receives a total wastewater load of 15.150 kg DBO day-1, from which 13.685 kg DBO day-1 (90.5%) corresponds to domestic sewage, and the city of São José do Rio Preto contributes with 12.400 kg DBO day-1 (90% of domestic sewage). During the period from August 1990 through January 1991, monthly sampling was carried out to evaluate the use of macroalgae as bioindicator of organic pollution. Five sampling sites were established along the main river and the following variables were analised: temperature, conductance, turbidity, dissolved oxygen, BOD, COD, total and fecal coliforms, and composition and abundance of macroalgal communities. Data were submitted to analysis of variance, correlation coefficient, cluster analysis (four different approaches) and converted to biological indices (species deficit, relative pollution, saprobity, diversity and uniformity indices). A wide range in water quality was found (particularly for conductance, oxygen, BOD and COD) among the sampling sites, which were classified into three groups (polluted, moderately polluted and unpolluted/weakly polluted). As regards the occurrence and abundance of macroalgae the Rhodophyta were found only in unpolluted or weakly polluted sites, whereas Cyanophyta occurred mostly under high pollution load; the Chlorophyta species were observed under a wide range of conditions. Among the biological indices, saprobity was the most sensitive and correlated to all water variables and the other indices. Cluster analyses showed that the composition of macroalgal communities was consistent with the levels of organic pollution in the Preto River.

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The presented article discuss theoretical context and the practical impact reported in the bibliography about Continued Progression at São Paulo State schools. Such proceeding, oriented through Law of Basic Guidelines, LBG, from 1996, previses a restructuring in the Basic Education at the schools, primarily with respect to evaluations. Grades are replaced for cycles and reprobation only can happen if the student exceeds the limit of stated absences or for lowered acting at final of each cycle. The impact of educational public policy drafted through Continued Progression provoke transformations that need more attention, indicating a path of reflection turned to structural conditions in order that school offers the required reinforcement to students and assure quality education. It’s primordial understand, therefore, the endogenous and exogenous factors that leaded to adoption of such proceeding in the São Paulo State.

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Podiumsdiskussion am Collegium Generale zur Thematik: Am Limit? Grenzen in den Wissenschaften heute. Teilnehmer: Prof. Dr. Gern Folkers, Direktor, Collegium Helveticum Prof. Dr. Angela Kalt, stv. Direktorin, Schweizerischer Nationalfonds Prof. Dr. Pasqualina Perrig-Chiello, Präsidentin, Network of Transdisciplinary Research

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[New research-results on the nonverbal fine-tuning between therapists and patients and the practice of paying attention to the nonverbal channel]

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Kognitive Interventionen haben sich bei der Behandlung von Schizophrenie als wirksam erwiesen und werden in nationalen Behandlungsleitlinien empfohlen. Viele Patienten mit Schizophrenie-Diagnose haben jedoch keinen Zugang zu ambulanten Psychotherapie-Plätzen nach stationären Klinikaufenthalten. Ein alternativer Zugangsweg zu kognitiven Interventionen sind Online- Selbsthilfe-Programme, welche sich bei anderen psychischen Störungen wie Depression und Angststörungen bereits als effektiv erwiesen haben. Im Rahmen einer Pilotstudie wird ein Symptom-orientiertes, KVT-basiertes Online-Selbsthilfe-Programm für Menschen mit Verfolgungsideen getestet. Das Programm besteht aus acht Einheiten und beinhaltet neben Psychose-bezogenen Inhalten (Störungsmodell, Rückfallprophylaxe, etc.) auch Einheiten zu Selbstwert, Umgang mit Sorgen und Schlafhygiene. Die TeilnehmerInnen werden wöchentlich von klinischen PsychologInnen per eMail kontaktiert (geleitete Selbsthilfe). Primäres Outcome-Maß ist das Ausmaß von Verfolgungswahn (Paranoia Checklist), sekundäre Outcome-Maße beinhalten Abbruchquoten, allgemeine Psychopathologie, Nebenwirkungen und Zufriedenheit. In die aktuell laufende Studie sollen insgesamt N=20 Teilnehmer eingeschlossen werden. Chancen und Einschränkungen von internet-basierter Selbsthilfe bei Psychose werden vor dem Hintergrund der vorläufigen Ergebnisse diskutiert.

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Las "orugas defoliadoras" afectan la producción del cultivo de soja, sobre todo en años secos y con altas temperaturas que favorecen su desarrollo. El objetivo del presente trabajo fue evaluar la eficiencia de control de insecticidas neurotóxicos e IGRs sobre "orugas defoliadoras" en soja. Se realizaron ensayos en lotes comerciales en tres localidades de la provincia de Córdoba en las campañas agrícolas 2008/09 y 2009/10, bajo un diseño de bloques al azar, con seis tratamientos y tres repeticiones. Los tratamientos fueron: T1: Clorpirifos (384 g p.a.ha-1), T2: Cipermetrina (37,5 g p.a.ha-1), T3: Lufenuron+Profenofos (15 + 150 g p.a.ha-1), T4: Metoxifenocide (28,8 g p.a.ha-1), T5: Novaluron (10 g p.a.ha-1) y T6: Testigo. El tamaño de las parcelas fue de 12 surcos de 10 m de largo distanciados a 0,52 m. La aplicación se realizó con una mochila provista de boquillas de cono hueco (40 gotas.cm-2), cuando la plaga alcanzó el umbral de daño económico. En cada parcela se tomaron cinco muestras a los 0, 2, 7 y 14 días después de la aplicación (DDA) utilizando el paño vertical, identificando y cuantificando las orugas vivas mayores a 1,5 cm. A los 14 DDA se extrajeron 30 folíolos por parcela (estrato medio y superior de la planta) y se determinó el porcentaje de defoliación utilizando el software WinFolia Reg. 2004. Se estimó el rendimiento sobre 5 muestras de 1 m2 en cada parcela y se realizó ANOVA y test de comparación de medias LSD de Fisher. El Clorpirifos mostró el mayor poder de volteo y el Metoxifenocide la mayor eficiencia a los 7 DDA. En general los IGRs mostraron mayor poder residual.