6,000 research outputs found
Diluted manganese on the bond-centered site in germanium
The functional properties of Mn-doped Ge depend to large extent on the lattice location of the Mn impurities. Here, we present a lattice location study of implanted diluted Mn by means of electron emission channeling. Surprisingly, in addition to the expected substitutional lattice position, a large fraction of the Mn impurities occupies the bond-centered site. Corroborated by ab initio calculations, the bond-centered Mn is related to Mn-vacancy complexes. These unexpected results call for a reassessment of the theoretical studies on the electrical and magnetic behavior of Mn-doped Ge, hereby including the possible role of Mn-vacancy complexes
Comparison of the efficiency of ozonation and catalytic ozonation (Mn II and Cu II) in phenol degradation.
This paper discusses the results obtained with homogeneous catalytic ozonation [Mn (II) and Cu (II)] in phenol degradation. The reduction of total phenols and total organic carbon (TOC) and the ozone consumption were evaluated. The efficiency in phenol degradation (total phenol removal) at pH 3, with the catalytic process (Mn (II)), increased from 37% to 55% while the TOC removal increased from 4 to 63% in a seven-minute treatment. The ozonation process efficiency at pH 10 was 43% and 39% for phenol and TOC removal, respectively. The presence of both metallic ions (Mn2+ and Cu2+) in the ozonation process resulted in a positive effect.291242
Use of gibberellin in floriculture
This review aimed to show the use of gibberellin in floriculture. In this context, it should be noted that the benefit of the activity of the gibberellins has brought major advances in the field of physiology. Its use is one of the most important tools for the development of agriculture. Thus, the study concluded that the use of gibberellins has been increasingly used by producers and is also a vast important subject that may help in increasing the production of flowers if the farms are dedicated to this purpose.Keywords: Regulators plants, flowers, phenotypic characteristics, postharves
Study of the vertical transport in p-doped superlattices based on group III-V semiconductors
The electrical conductivity Ï has been calculated for p-doped GaAs/Al0.3Ga0.7As and cubic GaN/Al0.3Ga0.7N thin superlattices (SLs). The calculations are done within a self-consistent approach to the kââ
pâ theory by means of a full six-band Luttinger-Kohn Hamiltonian, together with the Poisson equation in a plane wave representation, including exchange correlation effects within the local density approximation. It was also assumed that transport in the SL occurs through extended minibands states for each carrier, and the conductivity is calculated at zero temperature and in low-field ohmic limits by the quasi-chemical Boltzmann kinetic equation. It was shown that the particular minibands structure of the p-doped SLs leads to a plateau-like behavior in the conductivity as a function of the donor concentration and/or the Fermi level energy. In addition, it is shown that the Coulomb and exchange-correlation effects play an important role in these systems, since they determine the bending potential
mir152 hypomethylation as a mechanism for non-syndromic cleft lip and palate
Non-syndromic cleft lip with or without cleft palate (NSCLP), the most common human craniofacial malformation, is a complex disorder given its genetic heterogeneity and multifactorial component revealed by genetic, epidemiological, and epigenetic findings. Epigenetic variations associated with NSCLP have been identified; however, functional investigation has been limited. Here, we combined a reanalysis of NSCLP methylome data with genetic analysis and used both in vitro and in vivo approaches to dissect the functional effects of epigenetic changes. We found a region in mir152 that is frequently hypomethylated in NSCLP cohorts (21â26%), leading to mir152 overexpression. mir152 overexpression in human neural crest cells led to downregulation of spliceosomal, ribosomal, and adherens junction genes. In vivo analysis using zebrafish embryos revealed that mir152 upregulation leads to craniofacial cartilage impairment. Also, we suggest that zebrafish embryonic hypoxia leads to mir152 upregulation combined with mir152 hypomethylation and also analogous palatal alterations. We therefore propose that mir152 hypomethylation, potentially induced by hypoxia in early development, is a novel and frequent predisposing factor to NSCLP
Why are tapes better than wires in knotless rotator cuff repairs? An evaluation of force, pressure and contact area in a tendon bone unit mechanical model
Knotless repairs have demonstrated encouraging performance regarding retear rate reduction, but literature aiming at identifying the specific variables responsible for these results is scarce and conflictive. The purpose of this paper was to evaluate the effect of the material (tape or wire suture) and medial tendon passage (single or double passage) on the contact force, pressure and area at the tendon bone interface in order to identify the key factors responsible for this repairsÂŽ success.info:eu-repo/semantics/publishedVersio
Intermittent administration of parathyroid hormone improves the repairing process of rat calvaria defects: A histomorphometric and radiodensitometric study
BackgroundThe aim of this study was to evaluate the effects of intermittent treatment of parathyroid hormone (PTH (1-34)) on the bone regeneration of critically-sized rat calvarial bone defects.Material and MethodsThirty-two male rats were trephined (4mm fullthickness diameter), in the central part of the parietal bones and divided into 2 groups of 16. The PTH group received subcutaneous injections of PTH (1-34) at 40”g/kg, 3 times a week and the control (CTL) group received the vehicle in the same regimen. The rats were sacrificed at 4 weeks post-treatment regimen, the parietal bones were extracted and samples were evaluated through histomorphometry and radiodensitometry.ResultsThe histological observations showed that the PTH group presented more âisland-likeâ new bone between the defect margins with fibrous tissues than did the CTL group. The PTH group significantly exhibited greater histologic bone formation than did the CTL group (1.5mm ±0.7; 1.9 mm ± 0.6, p<0.05/ for residual bone defect). The radiodensitometry analysis revealed significant differences among the PTH and CTL groups (2.1 Al eq. ±0.04; 1.8Al eq. ±0.06, p<0.05), demonstrating an increase in bone mineral density. The PTH treatment contributed to the bone formation with a higher amount of mineral and/or fibrous tissue when compared with the CTL group.ConclusionsThe results suggest that it was possible to increase the process of bone regeneration by accelerating the healing process in rat calvarial defects through intermittent administration of the PTH treatment. Key words: Bone, skull, rats, bone regeneration, bone density
Geo-environmental mapping using physiographic analysis: constraints on the evaluation of land instability and groundwater pollution hazards in the Metropolitan District of Campinas, Brazil
Geo-environmental terrain assessments and territorial zoning are useful tools for the formulation and implementation of environmental management instruments (including policy-making, planning, and enforcement of statutory regulations). They usually involve a set of procedures and techniques for delimitation, characterisation and classification of terrain units. However, terrain assessments and zoning exercises are often costly and time-consuming, particularly when encompassing large areas, which in many cases prevent local agencies in developing countries from properly benefiting from such assessments. In the present paper, a low-cost technique based on the analysis of texture of satellite imagery was used for delimitation of terrain units. The delimited units were further analysed in two test areas situated in Southeast Brazil to provide estimates of land instability and the vulnerability of groundwater to pollution hazards. The implementation incorporated procedures for inferring the influences and potential implications of tectonic fractures and other discontinuities on ground behaviour and local groundwater flow. Terrain attributes such as degree of fracturing, bedrock lithology and weathered materials were explored as indicators of ground properties. The paper also discusses constraints on- and limitations of- the approaches taken
In vitro susceptibilities of Neoscytalidium spp. sequence types to antifungal agents and antimicrobial photodynamic treatment with phenothiazinium photosensitizers
Neoscytalidium spp. are ascomycetous fungi consisting of pigmented and hyaline varieties both able to cause skin and nail infection. Their colour-based identification is inaccurate and may compromise the outcome of the studies with these fungi. The aim of this study was to genotype 32 isolates morphologically identified as Neoscytalidium dimidiatum or Neoscytalidium dimidiatum var. hyalinum by multilocus sequence typing (MLST), differentiate the two varieties by their sequence types (STs), evaluate their susceptibility to seven commercial antifungal drugs [amphotericin B (AMB), voriconazole (VOR), terbinafine (TER), 5-flucytosine (5FC), ketoconazole (KET), fluconazole (FLU), and caspofungin (CAS)], and also to the antimicrobial photodynamic treatment (APDT) with the phenothiazinium photosensitizers (PSs) methylene blue (MB), new methylene blue (NMBN), toluidine blue O (TBO), and the pentacyclic derivative S137. The efficacy of each PS was determined, initially, based on its minimal inhibitory concentration (MIC). Additionally, the APDT effects with each PS on the survival of ungerminated and germinated arthroconidia of both varieties were evaluated. Seven loci of Neoscytalidium spp. were sequenced on MLST revealing eight polymorphic sites and six STs. All N. dimidiatum var. hyalinum isolates were clustered in a single ST. AMB, VOR, and TER were the most effective antifungal agents against both varieties. The hyaline variety isolates were much less tolerant to the azoles than the isolates of the pigmented variety. APDT with S137 showed the lowest MIC for all the isolates of both varieties. APDT with all the PSs killed both ungerminated and germinated arthroconidia of both varieties reducing the survival up to 5 logs. Isolates of the hyaline variety were also less tolerant to APDT. APDT with the four PSs also increased the plasma membrane permeability of arthroconidia of both varieties but only NMBN and S137 caused peroxidation of the membrane lipids. © 2017 British Mycological Society
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