Effect of preparation temperature and ions doping on size, morphology and catalytic activity of Co-B amorphous nano catalyst

Binary and quaternary amorphous nano powders are prepared by wet reduction method. Cobalt boride nano catalyst is synthesized at 10 and 60 ºC. Effect of preparation temperature on size and morphology was studied. Co-M-Zr-B (M: Cr, Mo and W) as quaternary catalysts are also prepared in order to studying ions doping on chemical and physical properties. Indeed, the obtained materials are characterized by XRD, FE-SEM, TEM, BET and ICP techniques. No distinct peak could be observed in XRD patterns indicating that the all catalysts possessed amorphous. The catalytic activity of the synthesized catalysts is investigated for the reduction reaction of 4-nitrophenol to 4-aminophenol in the presence of excess NaBH4 in aqueous medium at room temperature (298 K). It is found that our catalysts are highly active for high concentrations of 4-NP, 25-200 ppm. KEY WORDS: Amorphous, Nano catalyst, Metal boride, Reduction, Nitrophenol Bull. Chem. Soc. Ethiop. 2015, 29(1), 105-116DOI: http://dx.doi.org/10.4314/bcse.v29i1.

Monthly variations of total lipids content and some biological parameters of rock oyster (Saccostrea cucullata) in the Northern coasts of the Gulf of Oman

The present study was conducted to assess the monthly variations of total lipids content and some biological parameters of rock oyster in the Northern coasts of the Gulf of Oman (Iranian coast) from October 2017 until March 2018 in relation to environmental conditions. According to the results, the maximum and minimum lengths were recorded in December and February, respectively. The highest amounts of weight, dry and wet weight, and condition index were recorded in autumn. There was also a significant difference between the months and the regions for these parameters (p < 0.05). The highest amount of total lipids was observed in March (3.1±1.84) with a significant difference relative to October and November and the lowest amount one was observed in October (2.15±1.6). Also, there was a significant relationship between the total lipids and the temperature. Moreover, there were higher amounts of total lipids in Saccostrea cucullata in winter compared to those in autumn. In general, one of the reasons for the differences in length, weight and total lipids at different stations over different months can mainly be explained by the reproduction season, nutritional conditions, and environmental factors such as temperature and salinity.

Monthly variations of total lipids content and some biological parameters of rock oyster (Saccostrea cucullata) in the Northern coasts of the Gulf of Oman

465-472The present study was conducted to assess the monthly variations of total lipids content and some biological parameters of rock oyster in the Northern coasts of the Gulf of Oman (Iranian coast) from October 2017 until March 2018 in relation to environmental conditions. According to the results, the maximum and minimum lengths were recorded in December and February, respectively. The highest amounts of weight, dry and wet weight, and condition index were recorded in autumn. There was also a significant difference between the months and the regions for these parameters (p < 0.05). The highest amount of total lipids was observed in March (3.1±1.84) with a significant difference relative to October and November and the lowest amount one was observed in October (2.15±1.6). Also, there was a significant relationship between the total lipids and the temperature. Moreover, there were higher amounts of total lipids in Saccostrea cucullata in winter compared to those in autumn. In general, one of the reasons for the differences in length, weight and total lipids at different stations over different months can mainly be explained by the reproduction season, nutritional conditions, and environmental factors such as temperature and salinity

Dysfunctional stem and progenitor cells impair fracture healing with age

Successful fracture healing requires the simultaneous regeneration of both the bone and vasculature; mesenchymal stem cells (MSCs) are directed to replace the bone tissue, while endothelial progenitor cells (EPCs) form the new vasculature that supplies blood to the fracture site. In the elderly, the healing process is slowed, partly due to decreased regenerative function of these stem and progenitor cells. MSCs from older individuals are impaired with regard to cell number, proliferative capacity, ability to migrate, and osteochondrogenic differentiation potential. The proliferation, migration and function of EPCs are also compromised with advanced age. Although the reasons for cellular dysfunction with age are complex and multidimensional, reduced expression of growth factors, accumulation of oxidative damage from reactive oxygen species, and altered signaling of the Sirtuin-1 pathway are contributing factors to aging at the cellular level of both MSCs and EPCs. Because of these geriatric-specific issues, effective treatment for fracture repair may require new therapeutic techniques to restore cellular function. Some suggested directions for potential treatments include cellular therapies, pharmacological agents, treatments targeting age-related molecular mechanisms, and physical therapeutics. Advanced age is the primary risk factor for a fracture, due to the low bone mass and inferior bone quality associated with aging; a better understanding of the dysfunctional behavior of the aging cell will provide a foundation for new treatments to decrease healing time and reduce the development of complications during the extended recovery from fracture healing in the elderly

On the Effectiveness of Image Rotation for Open Set Domain Adaptation

Open Set Domain Adaptation (OSDA) bridges the domain gap between a labeled source domain and an unlabeled target domain, while also rejecting target classes that are not present in the source. To avoid negative transfer, OSDA can be tackled by first separating the known/unknown target samples and then aligning known target samples with the source data. We propose a novel method to addresses both these problems using the self-supervised task of rotation recognition. Moreover, we assess the performance with a new open set metric that properly balances the contribution of recognizing the known classes and rejecting the unknown samples. Comparative experiments with existing OSDA methods on the standard Office-31 and Office-Home benchmarks show that: (i) our method outperforms its competitors, (ii) reproducibility for this field is a crucial issue to tackle, (iii) our metric provides a reliable tool to allow fair open set evaluation.Comment: accepted at ECCV 202

6-Bromo-2-methyl­sulfanyl-1,3-benzo­thia­zole

The title mol­ecule, C8H6BrNS2, is almost planar with a dihedral angle of 0.9 (1)° between the benzene and thia­zole rings. The values of the geometry-based index of aromaticity (HOMA) and the nucleus-independent chemical shift (NICS) for the two cyclic fragments of the title mol­ecule are 0.95 and −9.61, respectively, for the benzene ring, and 0.69 and −7.71, respectively, for the thia­zole ring. They show that the benzene ring exhibits substanti­ally higher cyclic π-electron delocalization than the thia­zole ring. Comparison with other similar benzothia­zole fragments reveals a similar trend

Mechanical stimulation of human dermal fibroblasts regulates pro-inflammatory cytokines: potential insight into soft tissue manual therapies

Objective Soft tissue manual therapies are commonly utilized by osteopathic physicians, chiropractors, physical therapists and massage therapists. These techniques are predicated on subjecting tissues to biophysical mechanical stimulation but the cellular and molecular mechanism(s) mediating these effects are poorly understood. Previous studies established an in vitro model system for examining mechanical stimulation of dermal fibroblasts and established that cyclical strain, intended to mimic overuse injury, induces secretion of numerous pro-inflammatory cytokines. Moreover, mechanical strain intended to mimic soft tissue manual therapy reduces strain-induced secretion of pro-inflammatory cytokines. Here, we sought to partially confirm and extend these reports and provide independent corroboration of prior results. Results Using cultures of primary human dermal fibroblasts, we confirm cyclical mechanical strain increases levels of IL-6 and adding long-duration stretch, intended to mimic therapeutic soft tissue stimulation, after cyclical strain results in lower IL-6 levels. We also extend the prior work, reporting that long-duration stretch results in lower levels of IL-8. Although there are important limitations to this experimental model, these findings provide supportive evidence that therapeutic soft tissue stimulation may reduce levels of pro-inflammatory cytokines. Future work is required to address these open questions and advance the mechanistic understanding of therapeutic soft tissue stimulation

The supraclavicular flap for reconstruction of post-burn mentosternal contractures

Background: The thin and pliable skin of the neck is a region with multidirectional activity, and postburn scar contractures tend to form there easily. The supraclavicular flap is used to correct neck scar contractures. Its main vascular supply is the supraclavicular artery, and it can be harvested as either a skin pedicle flap or an island flap (vascular pedicle flap). Objective: In this article, a total of 41 flaps are studied retrospectively and their efficacy in reconstruction of post-burn neck scar contractures is discussed. Also donor-site morbidity, patient satisfaction, and complications were evaluated. Patients and Methods: Between November of 2004 and January of 2009, 41 supraclavicular flaps were used for reconstructions in 32 patients at the authors' hospital. Twenty-four of these flaps were skin pedicle flaps, and 17 were island flaps. The range of flap size was 18 ± 6 cm in length, and 9 ± 3 cm in width. Pre-expansion was performed in 14 flaps. Primary closure of donor site was performed in 35 flaps. Results: Thirty-seven of the 41 flaps survived completely, but there were three cases of distal necrosis (10-30), and one case of complete flap necrosis. Twenty-nine of the 32 patients were satisfied with both the functional and aesthetic results. Conclusions: Scarring of the neck produces problems with function, and appearance. In our view, the supraclavicular flap, a thin flap of good texture, is an excellent and highly reliable flap for covering defects of the anterior neck. This flap is easy to harvest, with good functional and aesthetic results. © 2013, Iranian Red Crescent Medical Journal