Scientists have traditionally studied complex biologic systems by reducing them to simple building blocks. Genome sequencing, high-throughput screening, and proteomics have, however, generated large ...datasets, revealing a high level of complexity in components and interactions. Systems biology embraces this complexity with a combination of mathematical, engineering, and computational tools for constructing and validating models of biologic phenomena. The validity of mathematical modeling in hematopoiesis was established early by the pioneering work of Till and McCulloch. In reviewing more recent papers, we highlight deterministic, stochastic, statistical, and network-based models that have been used to better understand a range of topics in hematopoiesis, including blood cell production, the periodicity of cyclical neutropenia, stem cell production in response to cytokine administration, and the emergence of imatinib resistance in chronic myeloid leukemia. Future advances require technologic improvements in computing power, imaging, and proteomics as well as greater collaboration between experimentalists and modelers. Altogether, systems biology will improve our understanding of normal and abnormal hematopoiesis, better define stem cells and their daughter cells, and potentially lead to more effective therapies.
Diabetes mellitus (DM) is defined as a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. This study was undertaken to ...explore the basic defect in type 2 diabetes patients in Bangladesh. This was an observational study with case control design, was conducted in the Biomedical Research Group, Research Division, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine Metabolic Disorders (BIRDEM), Dhaka, Bangladesh, during the period of July 2008 to June 2009. A total of 153 subjects were included in study of which 63 belonged to type 2 diabetes mellitus group and 90 were healthy controls. Fasting and 2 hours postprandial blood glucose, serum insulin, HOMA%B, HOMA%S, QuickI, Glucose /insulin ratio, TG were measured and age, BMI, WHR were recorded. Waist-hip ratio (WHR), was significantly higher in T2DM as compared to control subjects WHR, mean±SD, 0.94±0.12 vs. 0.88±0.06, p<0.001; Glucose and insulin ratio of T2DM was significantly higher as compared to control subject Glu: Ins, Median (range) of 0.54 (0.17-2.33) vs. 0.37(0.06-1.52). Insulin secretion (HOMA%B) was significantly lower in diabetic as compared to control subjects HOMA%B, median (range), 71(4.90-391) vs. 180(59-634) p<0.001; The quantitative insulin sensitivity check Index (QUICKI) of diabetic subjects were significantly higher as compared to control QUICKI median (range) 39.90(4.80-138.10) vs. 0.55(0.36-0.85), <0.001. Triglyceride (TG) and cholesterol (Chol) were significantly higher (mg/dl), (mean±SD), TG (142±80.14) vs. (142±80.14); Chol (189±50.76) vs. (172±45), p=0.029 in T2DM as compared to control subjects. Those with diabetes showed significant association with insulin secretory defect (HOMA%B, p=0.006) and insulin resistance as assessed by GINR (p<0.001) and QuickI (p<0.001) but not by HOMA%S (p=0.127). The present data suggest that both insulin secretory defect and insulin sensitivity are present in T2 diabetic subjects of Bangladesh.
A realistic assessment of the effect of curling stress on long-term performance of continuous reinforced concrete pavement (CRCP) is required in rational design. The main objective of this research ...is to quantify the thermal behavior of CRCP and the curling deflection fora bus rapid transit (BRT) lane. This study includes a field instrumentation effort with newly built CRCP equipped with temperature sensors and finite element (FE) analysis. Based on this study, the resultsshow the following: 1) the actual temperature distribution across the depth of CRCP is a second-order power function, considering the linear distribution for the calculation of curling stress can lead to an error of approximately 10%; 2) assuming the linear temperature distribution throughout the depth can be correct in the range of temperature differential of +2degreesC and -2degreesC; 3) the location of thermal gradient change and the neutral axis of CRCP section in the middle of slab are not the same, which can lead to great interior stress within pavement; 4) the maximum temperature gradient of CRCP during the day was determined to be twice that at night and these values were approximately 25 to 50% less than suggestedvalues by others; and 5) in designing minimum-maintenance CRCP, the combination of curling and loading stresses is necessary. Keywords: continuous reinforced concrete pavement (CRCP); curling stress; temperature gradient.
Two thiophenol-functionalized
trans
-platinum(II) bis(acetylide) complexes, having one thiophenol moiety in each alkenyl backbone with general formula
trans
-(PPh
3
)
2
Pt{C≡C–Ar–CH=CH(SC
6
H
5
)}
2
..., (
2a
–
2b
), (Ar = phenylene or 2,5-dimethylphenylene), were synthesized in good yields and good regioselectivities. Compared to the absorption bands of the
trans
-platinum(II) bis(acetylide) complexes
1
, the positions of the lowest energy absorption bands were redshifted by 17–18 nm, after functionalization with thiophenol. For both of the platinum(II) complexes
2
, the lowest energy absorption bands in chloroform solution at room temperature were observed in the range 376–379 nm, and under excitation at the absorption maximum both complexes showed emission maxima in the range of 408–419 nm. All the new Pt complexes have been characterized by physico-chemical and spectroscopic methods.
An experimental study was conducted to evaluate the performance of heat transfer for turbulent flow through a tube using air as the working fluid with perforated rectangular strip inserts. Mild steel ...rectangular strips of different pore diameters 2.1, 3.2, 4.25, 5.3, and 7.42 mm with corresponding porosities of 1.1%, 2.5%, 4.4%, 6.8%, and 13.3%, respectively, were used in the flow field. Heat transfer and pressure drop data were taken for Reynolds numbers ranging from 14,000 to 47,000. The experimental results showed that the Nusselt number, heat exchanger effectiveness, and friction factor were higher than those of the plain tube. The Nusselt number and the friction factor for employing the perforated strip inserts were found to be increased up to 2.65 and 1.75 times, respectively, over the corresponding plain tube. The heat transfer performance was evaluated and found to be 2.5 times higher compared to the plain tube based on the constant blower power. Finally, a correlation was developed with the experimental data for prediction of heat transfer in turbulent flow through a tube with perforated rectangular strip inserts.
Rain water samples were collected during the monsoon of 1994, using automatic wet-only and manual bulk collectors at a height of 30 m above the ground at the National Physical Laboratory, New Delhi. ...The average pH of the rain water was 5.7 and its chemical composition was dominated by NH
4 and SO
4. The free acidity of the rain water was found to be due to S04 rather than N03 and it was mainly neutralized by NH
4 and Ca. Calculation of sea salt fraction and enrichment factor revealed that this site is free for marine influence. On an average the bulk samples had 13% higher concentration than that of wet-only samples which may be due to the deposition of soil-derived particles during the 24 h period of exposure. The higher neutralization factors of Ca and Mg in bulk samples and highest dry deposition rates for Ca in comparison to other components, indicated the positive interference of dust particles in neutralization.
The density functional theory (DFT) was used to study the interaction of cysteine amino acid with (8, 0) zigzag single-walled BC
N nanotubes (BC
NNTs) both in gas and solvent phases. The interaction ...between cysteine amino acid and BC
NNTs is found to be energetically favorable in both phases. Based on the calculations of solvation energy, it can be seen that the dissolution of BC
NNT/amino acid complex in water is spontaneous. During the functionalization process, the quantum molecular descriptor and the energy of adsorption changed significantly. Findings suggest that the cysteine amino acid can be considerably adsorbed chemically onto the surface of BC
NNTs. Based on the E
values obtained, the cysteine molecule caused a reduction in the E
value, which also increased the reactivity and conductivity of functionalized BC
NNTs. According to the findings of chemical hardness, the kinetic stability of the functionalized nanotubes was better than pure nanotubes. As a result of this approach, E
values are indicative of high propensity reaction and electron transfer. Our findings have shown that BC
NNTs can function as an appropriate drug delivery system for cysteine amino acid within biological systems for the adsorption of the drug and controlled drug release.
PDF
