896 research outputs found
Cooling of a Nanomechanical Resonator in the Presence of a Single Diatomic Molecule
We propose a theoretical scheme for coupling a nanomechanical resonator to a
single diatomic molecule via microwave cavity mode of a driven LC resonator. We
describe the diatomic molecule by a Morse potential and find the corresponding
equations of motion of the hybrid system by using Fokker-Planck formalism.
Analytical expressions for the effective frequency and the effective damping of
the nanomechanical resonator are obtained. We analyze the ground state cooling
of the nanomechanical resonator in presence of the diatomic molecule. The
results confirm that presence of the molecule improves the cooling process of
the mechanical resonator. Finally, the effect of molecule's parameters on the
cooling mechanism is studied.Comment: 10 pages, 8 figure
Generating quantum discord between two distant Bose-Einstein condensates with Bell-like detection
We propose a technique that enables the creation of quantum discord between
two distant nodes, each containing a cavity consist of the Bose-Einstein
condensate, by applying a non-ideal Bell-like detection on the output modes of
optical cavities. We find the covariance matrix of the system after the
non-ideal Bell-like detection, showing explicitly that one enables manipulation
of the quantum correlations, and particularly quantum discord, between remote
Bose-Einstein condensates. We also find that the non-ideal Bell-like detection
can create entanglement between distant Bose-Einstein condensates at the two
remote site
Human Peripheral Blood Derived Hematopoietic Stem Cell: History, the Isolation Methods and Investigation of Different Parameters Effects on Their Differentiation to the Body Cells
Blood and the system that forms it, known as the hematopoietic system, consist of many cell types with specialized functions. Red blood cells (erythrocytes) carry oxygen to the tissues. Platelets (derived from megakaryocytes) help prevent bleeding. Granulocytes (neutrophils, basophils and eosinophils) and macrophages (collectively known as myeloid cells) fight infections from bacteria, fungi, and other parasites such as nematodes (ubiquitous small worms). Some of these cells are also involved in tissue and bone remodeling and removal of dead cells. B-lymphocytes produce antibodies, while T-lymphocytes can directly kill or isolate by inflammation cells recognized as foreign to the body, including many virus-infected cells and cancer cells. Many blood cells are short-lived and need to be replenished continuously; the average human requires approximately one hundred billion new hematopoietic cells each day. The continued production of these cells depends directly on the presence of Hematopoietic Stem Cells (HSCs), the ultimate, and only, source of all these. Peripheral blood stem cells (PBSC) are rapidly becoming the primary rescue modality for autologous transplantation and are now actively being investigated in the allogeneic transplant setting. Many investigators and clinical researchers believe that PBSC are likely to replace bone marrow stem cells entirely, for use in clinical transplantation in the not too distant. Hematopoietic stem cells (HSCs) are the blood cells that give rise to all the other blood cells. They give rise to the myeloid (monocytes and macrophages, neutrophils, basophils, eosinophils, erythrocytes, megakaryocytes/platelets, dendritic cells), and lymphoid lineages (T-cells, B-cells, NK-cells). The definition of hematopoietic stem cells has changed in the last two decades. The hematopoietic tissue contains cells with long-term and short-term regeneration capacities and committed multipotent, oligopotent, and unipotent progenitors
Isolation of rapid growing mycobacteria from soil and water in Iran
A total of 350 soil samples were collected from different part of Uremia city and suburbs. We used 3% sodium lauryl sulfate and 1% NaOH for decontamination of soil samples. Of 350 samples, mycobacteria were isolated from 65 (18.3%) specimens. Mycobacterium fortuitum with 18(5.14) strains yielded the highest frequency of isolation. The other isolates were: Mycobacterium peregrinum 11(3.14%), Mycobacterium flvescens 10 (2.85%), Mycobacterium chelonae 6 (1.71%), Mycobacterium mucogenicum 6(1.71%), Mycobacterium thermoresistable 4(1.14%), Mycobacterium abscessus 3 (0.85%), Mycobacterium neoaurum 2(0.57%), Mycobacterium smegmatis 2 (0.57%) and M. fortuitum third biovalant complex 3 (0.85%). The mean pH of soil was 7.89 ± 0.379 (max 8.5, min 7.5). Our data showed an abundant occurrence of mycobacteria in low pH (P value = 0001). We also collected 120 water samples from rivers, brooks and drinking water. Water samples decontaminated were by adding cetylpyridinium chloride (CPC) to give final concentration of 0.05%. Mycobacteria isolated from 12 water samples. The predominant isolated species were M. fortuitum and Mycobacterium cheloni. The majorityisolates were from brooks and surface waters
Association between vitamin A and E and apolipoprotein A and B levels in type 2 diabetes
Objective. To determine the relationship between serum vitamin A and E and apolipoprotein levels in type 2 diabetic patients. Setting. Shariati Hospital, Tehran, Iran. Subjects and methods. One hundred and seventeen eligible type 2 diabetic patients who attended the Endocrine Research and Metabolism Center between 2002 and 2004 were enrolled in the study. Blood samples were collected after a 12 - 14-hour overnight fast for the measurement of serum levels of total cholesterol, triglyceride, high-density lipoprotein (HDL), low-density lipoprotein (LDL), apolipoprotein (apo) A1 and apoB, and vitamins A and E. Anthropometric indices were determined by physical examination. Data were analysed statistically using Pearson's coefficient, multiple regression, and partial and bivariate correlations. Results. The mean body mass index (BMI) of the subjects was 27.4 ± 3.7 kg/m2. The mean (± standard deviation (SD)) serum levels of vitamins A and E were 0.5 ± 0.1 μg/ml and 9.5 ± 2.6 μg/ml, respectively. There were no significant differences in the plasma levels of vitamins A and E in males and females. Mean serum levels of vitamins A and E were within the normal range for both sexes. Serum lipid levels (total cholesterol, triglyceride and apoB) correlated with serum levels of vitamin E (p < 0.05). Serum levels of vitamins A and E were also correlated (p < 0.05). Standardised vitamin E levels showed significant negative correlation with most studied lipid profiles (p < 0.05). Conclusion. This study found that mean serum levels of the natural antioxidants vitamin E, and especially vitamin A, were close to the lower end of the normal range of these antioxidants in type 2 diabetics. Also, serum vitamin E and standardised vitamin E levels were important predictors of serum apoA1 levels in these patients. South African Journal of Clinical Nutrition Vol. 19(1) 2006: 39-4
Prevalence rate of white spot syndrome virus (WSSV) in farmed white leg shrimp (Litopenaeus vannamei) in Bushehr province
We surveyed presence of white spot syndrome virus (WSSV) in farmed white leg shrimp in Bushehr province with assumed a prevalence of 2% of virus in target population. Hence, 468 samples were collected in two separate phases from May to October 2006. In the first phase, 200 samples (each sample was 150 pieces of post larvae with average age 7 days) were taken from 3 active hatcheries and in the second phase, 268 samples from 418 ponds in 5 sites were collected. Samples were tested by "Nested PCR" for detection of WSSV with 1Q2000 commercial kits. Results were negative and with respect to sampling method and sensitivity and specifity of Nested PCR we concluded that cultured shrimps were free of WSSV in 2006 in Bushehr province
Predictive models for evaluation of mesophilic and psychrophilic bacterial loads in muscles of fresh ice-stored silver pomfret by impediometric technique
Current microbial methodologies to determine fish quality are laborious and have long time required to obtain results. The impediometric technique as a rapid sensitive method was used to determine the correlation between impedance detection times (IDTs) and conventional reference psychrophilic and mesophilic plate counts of fish in order to develop models for predicting the microbial quality and determining fish shelf-life. The changes in sensorial factors, psychrophilic and mesophilic bacterial loads of ice stored fresh silver pomfret (Pampus argenteus) were measured by two different methods including conventional reference plating techniques and also impediometric monitoring method at 0, 3, 6, 9, 12, 15, 18, 21, 24 and 27 days of storage. The primary psychrophilic (3.44 ± 0.69 logCFU/g) and mesophilic (3.64 ± 1.08 logCFU/g) bacterial loads increased to more than acceptable limit (6 logCFU/g) on days 12 and 21, respectively. The calibration curves for the two methods and their equations were designed with linear regression models. IDTs were highly correlated with psychrophilic (r=-0.9614) and mesophilic (r=-0.9547) bacterial loads. This study suggests that impediometric technique can be used as a rapid and reliable method to accurate estimation of silver pomfret bacterial loads and determine its shelf-life as seafood. According to results, the sensorial data were correlated with psychrophic bacterial load. The shelf-life of ice stored silver pomfret determined 9-12 days based on sensorial data and psychrophic bacterial load
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