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31.
Natural Convection Heat Transfer in a Porous Cavity with Sinusoidal Temperature Distribution Using Cu/Water Nanofluid: Double MRT Lattice Boltzmann Method 下载免费PDF全文
Hasan Sajjadi Amin Amiri Delouei Rasul Mohebbi Mohsen Izadi & Sauro Succi 《Communications In Computational Physics》2021,29(1):292-318
In this study, natural convection flow in a porous cavity with sinusoidal
temperature distribution has been analyzed by a new double multi relaxation time
(MRT) Lattice Boltzmann method (LBM). We consider a copper/water nanofluid filling a porous cavity. For simulating the temperature and flow fields, D2Q5 and D2Q9
lattices are utilized respectively, and the effects of different Darcy numbers (Da) (0.001-0.1) and various Rayleigh numbers (Ra) ($10^3$-$10^5$) for porosity ($ε$) between 0.4 and 0.9
have been considered. Phase deviation ($θ$) changed from 0 to $π$ and the volume fraction
of nanoparticles (Ø) varied from 0 to 6%. The present results show a good agreement
with the previous works, thus confirming the reliability the new numerical method
proposed in this paper. It is indicated that the heat transfer rate increases at increasing
Darcy number, porosity, Rayleigh number, the volume fraction of nanoparticles and
phase deviation. However, the most sensitive parameter is the Rayleigh number. The
maximum Nusselt deviation is 10%, 32% and 33% for Ra=$10^3$, $10^4$ and $10^5$, respectively, with $ε = 0.4$ to $ε = 0.9$. It can be concluded that the effect of Darcy number on
the heat transfer rate increases at increasing Rayleigh number, yielding a maximum
enhancement of the average Nusselt number around 12% and 61% for Ra=$10^3$ and
Ra=$10^5$, respectively. 相似文献
32.
Bhat IA Amin S Shah GN 《Indian journal of maternal and child health : official publication of Indian Maternal and Child Health Association,》1997,8(1):5-8
The nutritional status of 584 preschool children in an urban slum of Srinagar district was assessed through interviews of mothers conducted in a house-to-house survey, the clinical assessment of child nutritional status, and the anthropometric measurement of the children using accepted standard techniques. The anthropometric measurements of the children were compared to the 50th percentile of the Harvard Standard, while the classification recommended by the Indian Academy of Pediatrics was adopted for the categorization and grading of protein energy malnutrition. 60.45% of the children were malnourished, comprised of 33.22%, 20.89%, and 6.34% of children with grade I, II, and III degrees of malnutrition, respectively. Higher prevalence of malnutrition is associated with higher age, female sex, lower per capita income, higher birth order, and lower parental literacy. Parental literacy status followed by birth order and per capita income were the most important factors associated with preschool child malnutrition. 相似文献
33.
Primary malignant non-Hodgkin's lymphomas account for 0.4% of malignant neoplasms arising in the bladder and female urethra, but do not comprise a uniform group, and three subgroups can be identified which account for a majority of cases. The most common is a low-grade B-cell lymphoma similar to neoplasms arising in the mucosa-associated lymphoid tissue at other sites — so-called MALTomas. These generally display indolent behavior. A second group accounting for approximately one-fifth of cases is composed almost entirely of large lymphoid cells, and these tumors have a poor prognosis. A third possible group comprises only a few patients who present with diffuse thickening of the bladder wall, and have a poor prognosis. The authors present a new case which suggests that this latter group may be of T-cell origin. In addition to these three subtypes, others no doubt await recognition. The different forms of primary lymphoma appear to require different treatments, and some guidelines are proposed. 相似文献
34.
Ruhul AM Fukuda H Nakajima K Takatorige T Tatara K 《Environmental health and preventive medicine》1999,4(2):65-70
Health is one of the basic requirements for improvement in the quality of life. Since Bangladesh became independent, a policy
for providing essential minimum health care to all has been actively pursued.
An overview of Public Health Services in Bangladesh is presented in terms of: (1) a profile of the country, (2) an overview
of public health, (3) medical care, and (4) environmental health. Under each of these headings observations are included on
recent trends based upon relevant data and information.
Finally the authors describe the importance of (1) promotion of health care and planning at the national, divisional, local,
and community levels, (2) promotion of medical services at all levels, and (3) effective decentralization of health services
to enhance the services of health facilities. 相似文献
35.
36.
The effect of hyperbaric oxygen on medial collateral ligament healing in a rat model 总被引:1,自引:0,他引:1
Horn PC Webster DA Amin HM Mascia MF Werner FW Fortino MD 《Clinical orthopaedics and related research》1999,(360):238-242
Hyperbaric oxygen has been shown to promote healing in bone and some soft tissues. This study was undertaken to determine its effect on ligamentous healing. Forty-eight Sprague-Dawley rats underwent a standardized surgical laceration of the right (divided) medial collateral ligament, whereas the left (undivided) medial collateral ligament was not surgically lacerated. A control group of 24 rats recovered without intervention. An experimental group consisting of the other 24 rats was exposed to hyperbaric oxygen at 2.8 atmospheres for 1.5 hours a day for 5 days after the surgery. Six rats from each group were euthanized at 2, 4, 6, and 8 weeks. The stiffness and final force to failure were recorded for the divided and undivided medial collateral ligaments. At 4 weeks, a statistically greater force was required to cause failure of the previously divided ligaments that had been exposed to hyperbaric oxygen than those that had not. The stiffness and force to cause failure of previously divided ligaments were statistically greater at 4 weeks than at 2 weeks, whether or not hyperbaric oxygen was used. No additional statistical increases in stiffness or force were observed at 6 weeks. 相似文献
37.
Amin MB de Peralta-Venturina MN Ro JY El-Naggar A Mackay B Ordonez N Mani A Ayala A 《The American journal of surgical pathology》1999,23(12):1455-1463
Clear cell sarcoma of the kidney is a distinct, highly malignant pediatric neoplasm. Its occurrence in adults is extremely rare and the subject of isolated case reports. We present a series of four cases (three males and one female) identified in an adolescent and in young adults (16, 18, 20, and 25 years) with flank mass (three cases), hematuria (two cases), flank pain (two cases), and hypertension (one case). Three patients had stage III disease and one had stage I disease (National Wilms' Tumor Study staging system). All tumors had predominantly or exclusively the classic histology of a monotonous proliferation of uniform small round cells with evenly distributed fine chromatin, although focal microcyst formation (two cases) and spindled architecture (one case) (variant patterns) were also noted. Therapy in all cases consisted of surgery and chemotherapy with or without radiation. Follow-up data (29-202 months) showed distant metastases in all four cases, including the lung (four cases), bone (two cases), and the liver (two cases). Three patients died of disease at 29, 59, and 63 months (mean, 50.3 months), and one patient is alive with no evidence of disease at 202 months. Ultrastructural features included scattered primitive junctions, short and irregular cytoplasmic extensions, and scant to a moderate amount of mitochondria. Immunohistochemical study (three cases) showed immunoreactivity with vimentin (two cases) and no reaction with cytokeratin, epithelial membrane antigen, S-100 protein, or desmin. Flow cytometric analysis showed diploid DNA content in three primary tumors and tetraploidy in one metastatic tumor. The proliferative activity (S-phase fraction) was low to intermediate (mean, 9.8%). Our data suggest that clear cell sarcoma of the kidney in the young adult age group resembles its pediatric counterpart in ultrastructural and immunohistochemical characteristics, proclivity for skeletal and visceral metastasis, DNA diploid status with relatively low S-phase, and aggressive clinical course. Clear cell sarcoma of the kidney in adult patients, although rare, must be differentiated from sarcomatoid carcinoma, sarcomas, and round cell tumors because of its unique characteristics in comparison to other renal neoplasms. 相似文献
38.
A single hydrophobic residue confers barbiturate sensitivity to gamma-aminobutyric acid type C receptor 总被引:2,自引:0,他引:2
Amin J 《Molecular pharmacology》1999,55(3):411-423
Barbiturate sensitivity was imparted to the human rho1 homooligomeric gamma-aminobutyric acid (GABA) receptor channel by mutation of a tryptophan residue at position 328 (Trp328), which is located within the third transmembrane domain. Substitutions of Trp328 with a spectrum of amino acids revealed that nearly all hydrophobic residues produced receptor channels that were both directly activated and modulated by pentobarbital with similar sensitivities. Previous studies with ligand-gated ion channels (including GABA) have demonstrated that even conservative amino acid substitution within the agonist-dependent activation domain (N-terminal extracellular domain) can markedly impair agonist sensitivity. Thus, the lack of significant variation in pentobarbital sensitivity among the Trp328 mutants attests to an intrinsic difference between pentobarbital- and the GABA-dependent activation domain. Compared with the heterooligomeric alphabetagamma receptor channel, the mode of modulation for homooligomeric Trp328 mutants by pentobarbital was more dependent on the GABA concentration, yielding potentiation only at low concentrations of GABA (fractions of their respective EC50 values), yet causing inhibition at higher concentrations. Agonist-related studies have also demonstrated that residue 328 plays an important role in agonist-dependent activation, suggesting a functional interconnection between the GABA and pentobarbital activation domains. 相似文献
39.
Nadkarni JJ Perambakam SM Rathore VB Amin KM Parikh PM Naresh KN Advani SH 《Cancer biotherapy & radiopharmaceuticals》1998,13(4):269-274
The trafficking or homing of different lymphoid subsets to particular microenvironment is mediated by specific cell adhesion molecules (CAMs) expressed on lymphocytes and endothelial cells. B-cell chronic lymphocytic leukaemia (B-CLL) or Non-Hodgkin's lymphoma of small lymphocytic, B-cell type are monoclonal expansions of mature lymphocytes. The relative distribution of the tumor lymphocytes among various lymphoid compartments vary from patient to patient. Very few studies underlying this issue are available. To this effect, we have analysed the expression of LFA-1; VLA-4, ICAM-1; CD44H and CD44v6 (haematopoietic and variant form respectively) on freshly isolated lymphocytes obtained from bone marrow (BM), peripheral blood (PB) and lymph node (LN) by flow cytometry. Overall, we find strong expression of CD44H, low to moderate expression of LFA-1, negative to low expression of VLA-4 and lack of expression of CD44v6. ICAM-1 expression was observed only in patients with prominent lymphadenopathy. Higher expression of CD44H in PB lymphoid cells relative to that of BM lymphoid cells correlated with higher PB lymphocytosis (p < 0.001). Proliferating cell nuclear antigen expression in LN sections correlated inversely with VLA-4 expression on BM and PB lymphoid cells (p < 0.05). There was no significant correlation between expression of CAMs and bcl-2 protein. 相似文献
40.
Brainstem maturation after antenatal steroids exposure in premature infants as evaluated by auditory brainstem-evoked response. 总被引:2,自引:0,他引:2
Sanjiv B Amin Mark S Orlando Larry E Dalzell Kathleen S Merle Ronnie Guillet 《Journal of perinatology》2003,23(4):307-311
OBJECTIVE: Antenatal steroids result in fetal lung maturation, but may retard brain development. Auditory brainstem-evoked response (ABR) is a noninvasive assessment of brainstem maturation. The objective of this study was to determine if antenatal steroids affect brainstem maturation in infants =32 weeks gestational age (GA). DESIGN/METHODS: Bilateral monaural ABR were performed within the first 24 hours using 80 db nHL unfiltered click stimuli at a repetition rate of 39.9/seconds. ABR waveforms were categorized into Response Types based on response replicability and peak identification. Absolute wave latencies and interpeak latencies were measured when applicable. Data were collected for antenatal steroid exposure, mode of delivery, chorioamnionitis in utero, exposure to illicit drugs, exposure to magnesium sulfate, mechanical ventilation and 5 minute Apgar score <5 minute. Infants with TORCH infections, unstable conditions, and chromosomal disorders were excluded. RESULTS: Of 186 infants studied, 130 received antenatal steroids. Data were analyzed in 2 week GA intervals. There was a significant difference (P<0.05) in race (29 vs 39% African-American), birth weight (1231 vs 1416 gm) and use of magnesium sulfate (60 vs 32%) among infants who did and did not receive antenatal steroids, respectively. There was no significant difference in the other parameters measured. Even after controlling for confounding variables, there was no difference between absolute wave latencies or interpeak latencies between groups at either 28 to 29 weeks' or 30 to 31 weeks' postmenstrual age. There was no significant difference in frequency distribution of ABR waveform Response Types between groups. CONCLUSIONS: Antenatal steroids have neither a deleterious nor beneficial effect on brainstem maturation as measured by ABR in infants at =32 weeks GA. 相似文献