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121.
The Rectogordius (Foraminifera) abundance zone is described in the east of the Shishtu village in the Ozbak Kuh Mountain. The samples were collected in the Zaladou Formation., which is 60 m thick and composed of shales, sandstones, sandy limestones, microconglomerate, bioclastic limestones, coral limestone and fusulinid limestones. The Rectogordius abundance zone was found in sandy bioclastic limestone. It displays two species and three subspecies of this foraminifer, including Rectogordius iranicus, R. iranicus gadukensis, R. minimus and R. minimus shishtuensis n. subsp., R. iranicus ozbakensis n. subsp. The age of this abundance zone is considered to be Gzhelian, due to the distribution of Rectogordius in Central Iran (Ozbak Kuh; Zaladou Formation), central and eastern Alborz (Emarat Fm.), Sanandaj-Sirjan zone (Vazhnan Formation), as well as in the Donets, Arctic Canada, Afghanistan, and the Carnic Alps. The genus Rectogordius is possibly restricted to the northern Paleotethys margin, northern Cimmerian margin, shelf of the Uralian Ocean as far as the northernmost part of North America. Two new subspecies Rectogordius minimus shishtuensis n. subsp. and Rectogordius iranicus ozbakensis n. subsp. are described.  相似文献   
122.
The present study investigated the possible mediatory role of selenium (Se) in protecting plants from cadmium (Cd) toxicity. The exposure of sunflower seedlings to 20 μM Cd inhibited biomass production, decreased chlorophyll and carotenoid concentrations and strongly increased accumulation of Cd in both roots and shoots. Similarly, Cd enhanced hydrogen peroxides content and lipid peroxidation as indicated by malondialdehyde accumulation. Pre-soaking seeds with Se (5, 10 and 20 μM) alleviated the negative effect of Cd on growth and led to a decrease in oxidative injuries caused by Cd. Furthermore, Se enhanced the activities of catalase, ascorbate peroxidase and glutathione reductase, but lowered that of superoxide dismutase and guaiacol peroxidase. As important antioxidants, ascorbate and glutathione contents in sunflower leaves exposed to Cd were significantly decreased by Se treatment. The data suggest that the beneficial effect of Se during an earlier growth period could be related to avoidance of cumulative damage upon exposure to Cd, thus reducing the negative consequences of oxidative stress caused by heavy metal toxicity.  相似文献   
123.

Background  

This paper deals with the preprocessing of protein sequences for supervised classification. Motif extraction is one way to address that task. It has been largely used to encode biological sequences into feature vectors to enable using well-known machine-learning classifiers which require this format. However, designing a suitable feature space, for a set of proteins, is not a trivial task. For this purpose, we propose a novel encoding method that uses amino-acid substitution matrices to define similarity between motifs during the extraction step.  相似文献   
124.

Background

The ability of specific behaviour-change interventions to reduce HIV infection in young people remains questionable. Since January 1999, an adolescent sexual and reproductive health (SRH) intervention has been implemented in ten randomly chosen intervention communities in rural Tanzania, within a community randomised trial (see below; NCT00248469). The intervention consisted of teacher-led, peer-assisted in-school education, youth-friendly health services, community activities, and youth condom promotion and distribution. Process evaluation in 1999–2002 showed high intervention quality and coverage. A 2001/2 intervention impact evaluation showed no impact on the primary outcomes of HIV seroincidence and herpes simplex virus type 2 (HSV-2) seroprevalence but found substantial improvements in SRH knowledge, reported attitudes, and some reported sexual behaviours. It was postulated that the impact on “upstream” knowledge, attitude, and reported behaviour outcomes seen at the 3-year follow-up would, in the longer term, lead to a reduction in HIV and HSV-2 infection rates and other biological outcomes. A further impact evaluation survey in 2007/8 (∼9 years post-intervention) tested this hypothesis.

Methods and Findings

This is a cross-sectional survey (June 2007 through July 2008) of 13,814 young people aged 15–30 y who had attended trial schools during the first phase of the MEMA kwa Vijana intervention trial (1999–2002). Prevalences of the primary outcomes HIV and HSV-2 were 1.8% and 25.9% in males and 4.0% and 41.4% in females, respectively. The intervention did not significantly reduce risk of HIV (males adjusted prevalence ratio [aPR] 0.91, 95%CI 0.50–1.65; females aPR 1.07, 95%CI 0.68–1.67) or HSV-2 (males aPR 0.94, 95%CI 0.77–1.15; females aPR 0.96, 95%CI 0.87–1.06). The intervention was associated with a reduction in the proportion of males reporting more than four sexual partners in their lifetime (aPR 0.87, 95%CI 0.78–0.97) and an increase in reported condom use at last sex with a non-regular partner among females (aPR 1.34, 95%CI 1.07–1.69). There was a clear and consistent beneficial impact on knowledge, but no significant impact on reported attitudes to sexual risk, reported pregnancies, or other reported sexual behaviours. The study population was likely to have been, on average, at lower risk of HIV and other sexually transmitted infections compared to other rural populations, as only youth who had reached year five of primary school were eligible.

Conclusions

SRH knowledge can be improved and retained long-term, but this intervention had only a limited effect on reported behaviour and no significant effect on HIV/STI prevalence. Youth interventions integrated within intensive, community-wide risk reduction programmes may be more successful and should be evaluated.

Trial Registration

ClinicalTrials.gov NCT00248469 Please see later in the article for the Editors'' Summary  相似文献   
125.
Mutations of MYO6 are associated with recessive deafness,DFNB37   总被引:10,自引:0,他引:10       下载免费PDF全文
Cosegregation of profound, congenital deafness with markers on chromosome 6q13 in three Pakistani families defines a new recessive deafness locus, DFNB37. Haplotype analyses reveal a 6-cM linkage region, flanked by markers D6S1282 and D6S1031, that includes the gene encoding unconventional myosin VI. In families with recessively inherited deafness, DFNB37, our sequence analyses of MYO6 reveal a frameshift mutation (36-37insT), a nonsense mutation (R1166X), and a missense mutation (E216V). These mutations, along with a previously published missense allele linked to autosomal dominant progressive hearing loss (DFNA22), provide an allelic spectrum that probes the relationship between myosin VI dysfunction and the resulting phenotype.  相似文献   
126.
In post-core crown restorations, the significant mismatch between stiffness of artificial crowns and dental tissues leads to stress concentration at the interfaces. The aim of the present study was to reduce the destructive stresses by using a class of inhomogeneous materials called functionally graded materials (FGMs). For the purpose of the study, a 3-dimentional computer model of a premolar tooth and its surrounding tissues were generated. A post-core crown restoration with various crown materials, homogenous and FGM materials, were simulated and analyzed by finite element method. Finite element and statistical analysis showed that, in case of oblique loading, a significant difference (p < 0.05) was found at the maximum von Mises stresses of the crown margin between FGM and homogeneous crowns. The maximum von Mises stresses of the crown margin generated by FGM crowns were lower than those generated by homogenous crowns (70.8 vs. 46.3 MPa) and alumina crown resulted in the highest von Mises stress at the crown margin (77.7 MPa). Crown materials of high modulus of elasticity produced high stresses at the cervical region. FGM crowns may reduce the stress concentration at the cervical margins and consequently reduce the possibility of fracture.  相似文献   
127.
Chrysosporium tropicum was isolated from comb lesions in two different breeds of chickens in India and subcultures were shown to be pathogenic when inoculated onto prepared skin of guinea pigs. This report provides additional evidence to considerCh. tropicum as a pathogenic fungus and a probable cause of a dermatomycosis in chickens.  相似文献   
128.
Abstract

The present work aims to investigate the attractive ability of the newly isolated bacterium Serratia plymuthica BMA1, to release phosphorus (P) from rock phosphate (RP) and also to assess its beneficial effect in promoting the growth of Vicia faba. This strain exhibited the highest RP-solubilization activity ever reported, with 450?mg l?1 of soluble P at 30?°C. At 10 and 20?°C, its RP-solubilization was estimated at 100 and 200?mg l?1, respectively. HPLC analysis revealed that RP-solubilizing activity was associated with the release of gluconic acid. The hydroxyapatite (HA) solubilization activity concomitantly occurred with the secretion of gluconic acid and lactic acid. Under greenhouse conditions, application of BMA1 strain as an inoculant in presence of RP as the sole P source, considerably increased phosphorus uptake by V. faba L. and upgraded its overall growth in terms of dry weight and length by 76% and 39%, respectively. This growth promoting effect was accompanied by a substantial increase in chlorophyll contents. Additionally, phosphorus levels within roots and shoots of S. plymuthica BMA1-treated plants were approximately three times greater, compared to the non-inoculated control plants. When HA was used instead of RP, bacterization with BMA1 strain also enhanced the plant growth parameters and P contents, but significantly less than RP. These findings revealed that S. plymuthica BMA1 could be a potential candidate to improve the agronomic effectiveness of RP, toward a clean P-nutrition through the formulation of bio-phosphate fertilizers for plant growth promotion.  相似文献   
129.
130.
Pitfall traps baited with a lure containing a new pheromone component were used to catch adult Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae) in the field in Tanzania. Traps baited with a mixture of Trunc-call (T1) and the new component Trunc-call (T2) caught ten times as many insects as traps baited with T1 alone. The data demonstrate for the first time that mixtures of T1 and T2 can be used as effective lures to trap P. truncatus in the field, and that P. truncatus is widespread outside of farm buildings in Africa.
Résumé Des pièges contre P. truncatus Horn, appâtés avec un leurre contenant une nouvelle phéromone ont été utilisés dans la nature en Tanzanie. Les pièges appâtés avec un mélange de Trunc-call 1 (T1) et du nouveau composé Trunc-call 2 (T2) capturent 10 fois plus d'insectes que ceux appâtés avec T1 seul. Ces résultats montrent pour la première fois que des mélanges de T1 et T2 peuvent être utilisés efficacement pour leurrer P. truncatus dans la nature, et que P. truncatus est abondant autour des fermes en Afrique.
  相似文献   
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