Influence of management and environmental factors on mating success of Africanized queen honey bees

Environmental factors and management techniques were evaluated in São Paulo, Brazil, for enhanced production of Africanized queen honey bees. Queens were reared by the Doolittle method; 12 breeder, 6 cell-builder, and 36 3-frame nucleus colonies were used. Nine groups of four virgin Africanized queen honey bees were subjected to the following treatments: queens were either 1-2, 3-4 or 5-6 days old and were released into mating nuclei containing either capped brood, uncapped brood or no brood. This was repeated sixteen times between August 1990 and August 1992. Seven repetitions occurred during nectar flow periods and nine repetitions occurred during nectar-dearth periods. Overall, 59% of 576 queens were successfully introduced and mated. The best results (93% success) were obtained during nectar flows, with 3- to 4-day-old queens released into nuclei containing capped brood. During nectar dearths the best mating success came from queens introduced into broodless nuclei (63%), the age of the queen did not influence mating success. Mating success decreased when wind velocity increased; this was the only significant meteorological effect found.

Influence of early qualitative feed restriction and environmental temperature on long bone development of broiler chickens

This investigation was carried out to study the influence of early qualitative feed restriction and environmental rearing temperature on long bone development in broiler. Energy and protein restriction reduced femur width and humerus weight, but did not affect tibia parameters. Broilers kept at cold environmental temperature showed reduced femur, tibia and humerus length and tibia weight, but the calculated density was not affected by rearing temperature. These findings suggest that qualitative feed restriction and environmental temperature influenced the normal long bone growth; however, bone weight/bone length index (calculated density) was not affected by rearing temperature. (c) 2007 Elsevier Ltd. All rights reserved.

Influence of Environmental Conditioning on the Shear Behavior of Poly(phenylene sulfide)/Glass Fiber Composites

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of viscoelastic characteristics of the colloidal suspensions on the formation of SnO2 supported membranes

SnO2 supported membranes have been prepared by sol-casting on alumina tubular substrate, using aqueous colloidal suspensions prepared by sol-gel route. The viscoelastic behaviour during sol ageing was analyzed by dinamic rheologial measurements. The complex viscosity and the storage and loss moduli have been followed during the sol-gel transition and the results have been correlated with the linear aggregates growth and the scalar percolation models. The scanning electron microscopy has evidenced that the homogeneity and thickness of the membrane depend on the sol ageing time. Crack-free and homogeneous membranes have been obtained for coated layers of 0.5μm thickness. © 1997 Trans Tech Publications.

Influence of chromate, molybdate and tungstate on pit formation in chloride medium

It has been characterized and evaluated the 2024-T351 and 7050-T7451 aluminum alloys pitting corrosion in naturally aerated chloride aqueous solutions containing chromate, molybdate and tungstate. It has been carried out electrochemical and non-electrochemical immersion corrosion tests accompanied by surface metallography analysis using an optical microscopy. Chromate for the two alloys and in molybdate for 7050 has corrosion inhibiting effects, whereas tungstate promotes the pitting corrosion for these alloys. Quantitative surface analysis upon the alloys after immersion has indicated that pits are predominantly conical or quasi-conical and irregular. In general, pits have been wider than deep and the widest have been also the deepest. Despite inhibitor presence, when pits have been nucleated, they grow with the same intensity. © 2005 Elsevier B.V. All rights reserved.

CROSSOVER CLINICAL TRIAL OF THE INFLUENCE OF THE USE OF ADHESIVE ON BIOFILM FORMATION

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The Influence of Osteoblast Differentiation Stage on Bone Formation in Autogenously Implanted Cell-Based Poly(Lactide-Co-Glycolide) and Calcium Phosphate Constructs

We tested the hypothesis that the osteoblast differentiation status of bone marrow stem cells (BMSCs) combined with a three-dimensional (3D) structure modulates bone formation when autogenously implanted. Rat BMSCs were aspirated, expanded, and seeded into a 3D composite of poly(lactide-co-glycolide) and calcium phosphate (PLGA/CaP) to produce a hybrid biomaterial. Calvarial defects were implanted with (1) scaffold without cells (SC/NC), (2) scaffold and BMSCs (SC + BMSC), (3) scaffold and osteoblasts differentiated for 7 days (SC + OB7), and (4) for 14 days (SC + OB14). After 4 weeks, there was more bone formation in groups combining scaffold and cells, SC + BMSC and SC + OB7. A nonsignificant higher amount of bone formation was observed on SC + OB14 compared with SC/NC. Additionally, more blood vessels were counted within all hybrid biomaterials, without differences among them, than into SC/NC. These findings provide evidences that the cell differentiation status affects in vivo bone formation in autogenously implanted cell-based constructs. Undifferentiated BMSCs or osteoblasts in early stage of differentiation combined with PLGA/CaP scaffold favored bone formation compared with plain scaffold and that one associated with more mature osteoblasts.

Influence of plant structure, cultural pratices and environmental conditions on the development of the bacterial canker of kiwifruits

Italy has a preeminent rank in kiwifruit industry, being the first exporter and the second largest producer after China. However, in the last years kiwifruit yields and the total cultivated area considerably decreased, due to the pandemic spread of the bacterial canker caused by Pseudomonas syringae pv. actinidiae (Psa). Several climatic conditions and cultural practices affect the development of the bacterial canker. This research work focused on the impact of agricultural practices and microclimate conditions on the incidence and epidemiology of Psa in the orchard. Therefore, the effect of fertilization, irrigation, use of bio-regulators, rootstock, training system and pruning were examined. The effect of different tunnel systems was analyzed as well, to study the plant-pathogen interaction. Considering the importance of insects as vectors in other pathosystems, the role of Metcalfa pruinosa in the spread of the bacterial canker was investigated in controlled conditions. In addition, quality and storage properties of fruits from infected plants were assessed. The study of all these aspects of the agronomic practices is useful to define a strategy to limit the bacterial diffusion in the orchard. Overall, excess nitrogen fertilization, water stress, stagnant water supplies, pruning before summer and the high number of Metcalfa pruinosa increased the Psa incidence. In contrast, tunnel covers may be useful for the control of the disease, with special attention to the kind of material.

Influence of micro-site conditions and environmental gradients on tree-ring based climate reconstructions

Tree-ring chronologies are a powerful natural archive to reconstruct summer temperature variations of the late Holocene with an annual resolution. To develop these long-term proxy records tree-ring series are commonly extended back in time by combining samples from living trees with relict dead material preserved onshore or in lakes. Former studies showed that low frequency variations in such reconstructions can be biased if the relict and recent material is from different origins. A detailed analysis of the influence of various ecological (micro-) habitats representing the recent part is required to estimate potential errors in temperature estimates. The application of collective detrending methods, that comprise absolute growth rates, can produce errors in climate reconstructions and results in an underestimation of past temperatures. The appearance of these kind of micro-site effects is a wide-spread phenomenon that takes place all over Fennoscandia. Future research in this key region for dendroclimatology should take this issue into account. Especially the higher climate response at the lakeshore site is interesting to achieve smaller uncertainties when a tree-ring series is transformed to temperature anomalies. For new composite chronologies the main aim should be to minimize potential biases and this includes also micro-site effects.

Influence of rhBMP-2 on bone formation and osseointegration in different implant systems after sinus-floor elevation. An in vivo study on sheep

Several studies have reported certain bone morphogenic proteins (BMPs) to have positive effects on bone generation. Although some investigators have studied the effects of human recombinant BMP (rhBMP-2) in sinus augmentation in sheep, none of these studies looked at the placement of implants at the time of sinus augmentation. Furthermore, no literature could be found to report on the impact that different implant systems, as well as the positioning of the implants had on bone formation if rhBMP-2 was utilized in sinus-lift procedures.

Influence of Gilbert's syndrome on the formation of ethyl glucuronide.

A drinking experiment with participants suffering from Gilbert's syndrome was performed to study the possible influence of this glucuronidation disorder on the formation of ethyl glucuronide (EtG). Gilbert's syndrome is a rather common and, in most cases, asymptomatic congenital metabolic aberration with a prevalence of about 5 %. It is characterized by a reduction of the enzyme activity of the uridine diphosphate glucuronosyltransferase (UGT) isoform 1A1 up to 80 %. One of the glucuronidation products is EtG, which is formed in the organism following exposure to ethanol. EtG is used as a short-term marker for ethyl alcohol consumption to prove abstinence in various settings. After 2 days of abstinence from ethanol and giving a void urine sample, 30 study participants drank 0.1 L of sparkling wine (9 g ethanol). 3, 6, 12, and 24 h after drinking, urine samples were collected. 3 hours after drinking, an additional blood sample was taken, in which liver enzyme activities, ethanol, hematological parameters, and bilirubin were measured. EtG and ethyl sulfate (EtS), another short-term marker of ethanol consumption, were determined in the urine samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS); creatinine was measured photometrically. In all participants, EtG and EtS were detected in concentrations showing a wide range (EtG: 3 h sample 0.5-18.43 mg/L and 6 h sample 0.67-13.8 mg/L; EtS: 3 h sample 0.87-6.87 mg/L and 6 h sample 0.29-4.48 mg/L). No evidence of impaired EtG formation was found. Thus, EtG seems to be a suitable marker for ethanol consumption even in individuals with Gilbert's syndrome.

Environmental control on the occurrence of high-coercivity magnetic minerals and formation of iron sulfides in a 640 ka sediment sequence from Lake Ohrid (Balkans)

The bulk magnetic mineral record from Lake Ohrid, spanning the past 637 kyr, reflects large-scale shifts in hydrological conditions, and, superimposed, a strong signal of environmental conditions on glacial–interglacial and millennial timescales. A shift in the formation of early diagenetic ferrimagnetic iron sulfides to siderites is observed around 320 ka. This change is probably associated with variable availability of sulfide in the pore water. We propose that sulfate concentrations were significantly higher before  ∼  320 ka, due to either a higher sulfate flux or lower dilution of lake sulfate due to a smaller water volume. Diagenetic iron minerals appear more abundant during glacials, which are generally characterized by higher Fe / Ca ratios in the sediments. While in the lower part of the core the ferrimagnetic sulfide signal overprints the primary detrital magnetic signal, the upper part of the core is dominated by variable proportions of high- to low-coercivity iron oxides. Glacial sediments are characterized by high concentration of high-coercivity magnetic minerals (hematite, goethite), which relate to enhanced erosion of soils that had formed during preceding interglacials. Superimposed on the glacial–interglacial behavior are millennial-scale oscillations in the magnetic mineral composition that parallel variations in summer insolation. Like the processes on glacial–interglacial timescales, low summer insolation and a retreat in vegetation resulted in enhanced erosion of soil material. Our study highlights that rock-magnetic studies, in concert with geochemical and sedimentological investigations, provide a multi-level contribution to environmental reconstructions, since the magnetic properties can mirror both environmental conditions on land and intra-lake processes.