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91.
92.
Humans utilize facial appearance, gender, expression, aging pattern, and other ancillary information to recognize individuals. It is interesting to observe how humans perceive facial age. Analyzing these properties can help in understanding the phenomenon of facial aging and incorporating the findings can help in designing effective algorithms. Such a study has two components - facial age estimation and age-separated face recognition. Age estimation involves predicting the age of an individual given his/her facial image. On the other hand, age-separated face recognition consists of recognizing an individual given his/her age-separated images. In this research, we investigate which facial cues are utilized by humans for estimating the age of people belonging to various age groups along with analyzing the effect of one''s gender, age, and ethnicity on age estimation skills. We also analyze how various facial regions such as binocular and mouth regions influence age estimation and recognition capabilities. Finally, we propose an age-invariant face recognition algorithm that incorporates the knowledge learned from these observations. Key observations of our research are: (1) the age group of newborns and toddlers is easiest to estimate, (2) gender and ethnicity do not affect the judgment of age group estimation, (3) face as a global feature, is essential to achieve good performance in age-separated face recognition, and (4) the proposed algorithm yields improved recognition performance compared to existing algorithms and also outperforms a commercial system in the young image as probe scenario. 相似文献
93.
Ram Krishna Thakur Vinod Kumar Yadav Akinchan Kumar Ankita Singh Krishnendu Pal Luke Hoeppner Dhurjhoti Saha Gunjan Purohit Richa Basundra Anirban Kar Rashi Halder Pankaj Kumar Aradhita Baral MJ Mahesh Kumar Alfonso Baldi Bruno Vincenzi Laura Lorenzon Rajkumar Banerjee Praveen Kumar Viji Shridhar Debabrata Mukhopadhyay Shantanu Chowdhury 《Nucleic acids research》2014,42(18):11589-11600
94.
Point mutations within the pore region of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel have previously been shown to alter the selectivity of the channel between different anions, suggesting that part of the pore may form an anion 'selectivity filter'. However, the full extent of this selectivity filter region and the location of anion binding sites in the pore are currently unclear. As a result, comparisons between CFTR and other classes of Cl(-) channel of known structure are difficult. We compare here the effects of point mutations at each of eight consecutive amino acid residues (arginine 334-serine 341) in the crucial sixth transmembrane region (TM6) of CFTR. Anion selectivity was determined using patch-clamp recording from inside-out membrane patches excised from transiently transfected mammalian cell lines. The results suggest that selectivity is predominantly controlled by a single site involving adjacent residues phenylalanine 337 and threonine 338, and that the selectivity conferred by this 'filter' region is modified by anion binding to flanking sites involving the more extracellular arginine 334 and the more intracellular serine 341. Other residues within this part of the pore play only minor roles in controlling anion permeability and conductance. Our results support a model in which specific TM6 residues make important contributions to a single, localized anion selectivity filter in the CFTR pore, and also contribute to multiple anion binding sites both within and on either side of the filter region. 相似文献
95.
Jagdish Ojha Narendra Mishra Mahadeo Prasad Saha Jyoti Swarup Datta Munshi 《Hydrobiologia》1979,63(2):153-159
Oxygen uptake of Channa marulius was studied under water with and without access to air. There was a significant increase in the oxygen uptake through the gills when access to air was prevented. However, this value (0.863 ± 0.058 mlO2/indiv./h) was quite low in comparison to the total bimodal oxygen uptake (2.04 ± 0.14 mlO2/indiv./h) in juveniles. In adult fish the oxygen uptake per unit time increased appreciably (4.673 ± 0.404 mlO2/indiv./h). In juveniles as well as in adults the air breathing dominated over aquatic breathing. This fish showed a definite circadian rhythm in the bimodal oxygen uptake during different hours of the day.This work was performed in the Ichthyology Laboratory, P. G. Dept. of Zoology, Bhagalpur University, and was supported by a research grant from Bhagalpur University 相似文献
96.
H. Singh N. B. Singh A. Singh I. Hussain V. Yadav 《Russian Journal of Plant Physiology》2017,64(4):518-524
The present study assessed the response of pea plants exposed to herbicide induced oxidative stress in the plants present in agriculture field. We analysed the effect of exogenous nitric oxide (NO) regulated chlorophyll and protein content, nitrate reductase enzyme activity and antioxidant enzyme activity in herbicidetreated green pea (Pisum sativum L.). Glyphosate (0.25 mM) treatment alone or in combination with 250 μM sodium nitroprusside (SNP, 250 μM with glyphosate) was given to pea and we observed the changes in biophysical and biochemical parameters. During oxidative stress ion leakage is the first step of cellular damage. Supplementation of SNP with glyphosate significantly reduced ion leakage and moderately reduced H2O2 and malondialdehyde (MDA) content. SNP also increased chlorophyll content and antioxidant enzymes viz. superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (POD) activity as compared to herbicide treatment alone. The present result suggests that NO protects pea plants from damage caused by glyphosate. 相似文献
97.
98.
Shivmurat Yadav Konica Porwal Rohit Anthony Sinha Naibedya Chattopadhyay Sushil Kumar Gupta 《Biochemistry and Biophysics Reports》2021
Adequate dietary calcium (Ca) intake is essential for bone accretion, peak bone mass (PBM) attainment, bone quality and strength during the mammalian growth period. Severe Ca deficiency during growing age results in secondary hyperparathyroidism (SHPT) and poor bone quality and strength. However, the impact of moderate Ca deficiency during rats early growth period on bone health and the reversibility with supplementing calcium later in adult life remains unclear. Female Sprague-Dawley (SD) rats (postnatal 28th day, P28) were initiated either with a moderate calcium-deficient diet (MCD, 0.25% w/w Ca) or a control diet (0.8% w/w Ca, control group) till P70. Thereafter, MCD rats were continued either with MCD diet or supplemented with calcium diet (0.8% w/w Ca, calcium supplemented group, CaS) till P150. Another group (control rats) were fed 0.8% w/w Ca containing diet from P28 till P150.MCD group, as compared to the control group, had significantly reduced serum ionized Ca and procollagen type 1 N-terminal propeptide (P1NP) at P70 while no significant change was observed in serum corrected Ca, inorganic phosphate (P), alkaline phosphatase (ALP), 25-hydroxy vitamin D [25(OH)D], intact parathyroid hormone (iPTH), and urinary C-terminal telopeptide of collagen 1 (CTX-1), Ca, and P. Femoral and tibial metaphysis in MCD rats had significantly reduced linear growth, cortical and trabecular volumetric BMD (vBMD), trabecular microarchitecture (BV/TV%, trabecular thickness, separation and number, structural model index and connectivity density), cortical thickness, and bone stiffness despite the absence of secondary hyperparathyroidism (SHPT). Continued MCD at P70–P150 results in persistence of compromised bone strength while calcium supplementation (CaS group) improved all the parameters related to bone strength and microarchitecture. Our results indicate that uncorrected moderate/subclinical calcium deficiency in growing rats can result in poor bone quality and strength despite the absence of SHPT. This finding could have relevance in children with poor calcium intake in childhood and adolescence. 相似文献
99.
100.
Shreyasi Asthana Zaved Hazarika Parth Sarathi Nayak Jyoti Roy Anupam Nath Jha Bibekanand Mallick Suman Jha 《Biochimica et Biophysica Acta (BBA)/General Subjects》2019,1863(1):153-166