Significance of vascular endothelial growth factor and CD31 and morphometric analysis of microvessel density by CD31 receptor expression as an adjuvant tool in diagnosis of psoriatic lesions of skin

Background: Pathogenesis of psoriasis is a debated issue. Several mechanisms have been proposed to identify the etiology and pathogenesis so that specific treatments can be given to patients with psoriasis. Aims: (1) To compare pattern and distribution of vascular endothelial growth factor (VEGF) and CD31 in patients with psoriasis and other psoriasiform lesions of skin. (2) To study the correlation between VEGF and CD31 expression, clinical severity, and histopathology of psoriasiform lesions of skin. (3) Evaluation of microvessel density (MVD) by using computer-assisted quantitative image analysis in psoriatic skin lesions. Materials and Methods: This study was conducted on eighty cases, out of which forty were diagnosed cases of psoriasis and forty cases of clinically suspected psoriasiform lesions, submitted in the Department of Pathology, Pt. B.D. Sharma, University of Health Sciences, Rohtak, for histopathological examination. Histopathological sections were stained by routine hematoxylin and eosin staining, and these biopsies were further subjected to immunohistochemical staining with VEGF and CD31 as per standard technique. Results: Assessment of various histopathological features revealed strong correlation between epidermal hyperplasia, suprapapillary thinning, and elongation of rete ridges. Suprabasilar keratinocytes in psoriatic lesions stained intensely for VEGF. The difference for number of microvessels and MVD in psoriasis and psoriasiform lesions was statistically significant. Correlation between intensity of VEGF staining by suprabasilar keratinocytes and MVD was found to be highly significant in psoriatic lesions. Conclusion: The present study concluded that psoriatic lesions exhibit potent angiogenic activity. Early lesions show increased MVD along with other histomorphological parameters such as hypogranulosis, parakeratosis and Munro's microabscesses. Overexpression of VEGF by suprabasilar keratinocytes correlated with increased MVD in papillary dermis

Influence of Different Grades of CBN Inserts on Cutting Force and Surface Roughness of AISI H13 Die Tool Steel during Hard Turning Operation

Now-a-days, the application of hard tuning with CBN tool has been massively increased because the hard turning is a good alternative to grinding process. However, there are some issues that need to be addressed related to the CBN grades and their particular applications in the area of hard turning process. This experimental study investigated the effects of three different grades of CBN insert on the cutting forces and surface roughness. The process of hard turning was made using the AISI H13 die tool steel at containing different hardness (45 HRC, 50 HRC and 55 HRC) levels. The work material were selected on the basis of its application in the die making industries in a range of hardness of 45–55 HRC. Optimization by the central composite design approach has been used for design and analysis. The present study reported that the cutting forces and surface roughness are influenced by the alloying elements and percentage of CBN in the cutting tool material. The work material hardness, feed rate and cutting speed are found to be statistically significant on the responses. Furthermore, a comparative performance between the three different grades of CBN inserts has been shown on the cutting forces and surface roughness at different workpiece hardness. To obtain the optimum parameters from multiple responses, desirability approach has been used. The novelty/robustness of the present study is represented by its great contribution to solve practical industrial application when is developed a new process using different CBN grades for hard turning and die makers of workpiece having the hardness between 45 and 55 HRC

Hole extraction by design in photocatalytic architectures interfacing CdSe quantum dots with topochemically stabilized tin vanadium oxide

Tackling the complex challenge of harvesting solar energy to generate energy-dense fuels such as hydrogen requires the design of photocatalytic nanoarchitectures interfacing components that synergistically mediate a closely interlinked sequence of light-harvesting, charge separation, charge/mass transport, and catalytic processes. The design of such architectures requires careful consideration of both thermodynamic offsets and interfacial charge-transfer kinetics to ensure long-lived charge carriers that can be delivered at low overpotentials to the appropriate catalytic sites while mitigating parasitic reactions such as photocorrosion. Here we detail the theory-guided design and synthesis of nanowire/quantum dot heterostructures with interfacial electronic structure specifically tailored to promote light-induced charge separation and photocatalytic proton reduction. Topochemical synthesis yields a metastable β-Sn0.23V2O5 compound exhibiting Sn 5s-derived midgap states ideally positioned to extract photogenerated holes from interfaced CdSe quantum dots. The existence of these midgap states near the upper edge of the valence band (VB) has been confirmed, and β-Sn0.23V2O5/CdSe heterostructures have been shown to exhibit a 0 eV midgap state-VB offset, which underpins ultrafast subpicosecond hole transfer. The β-Sn0.23V2O5/CdSe heterostructures are further shown to be viable photocatalytic architectures capable of efficacious hydrogen evolution. The results of this study underscore the criticality of precisely tailoring the electronic structure of semiconductor components to effect rapid charge separation necessary for photocatalysis