A Heuristic for a Class of Production Planning and Scheduling Problems

This paper describes a solution technique for a general class of problems referred to as aggregate planning and master scheduling problems. The technique is also applicable to multi-item single level capacitated lot sizing problems. The solution technique presented here is a heuristic that is practical for large problems e.g. 9 products and 36 periods. We have tested it for problems with varying number of time periods, number of products, setup costs, holding costs, overtime costs and capacity levels. For those problems that we could solve exactly using a branch and bound algorithm, the solutions produced by the heuristic were all within 1 % of optimality. For problems that we could not solve exactly, we are able to compute a lower bound on the optimal cost. Using the bound we are able to show that our heuristic solutions were within 2.93% of optimality on the average. Except for those problems having very high setup cost or problems with extreme seasonality, the algorithm produced solutions that were within 1 % of optimality on average.     

Weight loss and metabolic profiles in obese individuals using two different approaches

Intentional weight loss with a reduction in adipose tissue is associated with an improvement in medical complications linked to obesity. The aim of this study was to compare the effect of two different weight loss diets on obese individuals (BMI 30-40 kg m(-2)) for improvements in anthropometric measurements and blood biomarkers. Study 1 comprised a low energy diet (LED) of 5000-6000 kJ d(-1) for a slow but steady weight loss over 12 weeks. Study 2 comprised a very low energy diet (VLED) of 3000 kJ d(-1) using meal replacements for rapid weight loss over a shorter period of 4 weeks followed by 10 weeks of weight stabilisation to prevent rebound after rapid weight loss. Nutrition information sessions were given to both groups. Fasting blood samples, anthropometric measurements and 3-day food diaries were collected at baseline and again at completion of weight loss, at 12 weeks for LED group and 4 weeks for VLED group. Mean weight loss in the LED group (n = 18) was -3.17 kg (-3.7%) compared to a -6.54 kg (-7%) loss in the VLED group (n = 14) (p < 0.001). The VLED group experienced significantly greater reductions in fat mass, -13.9% compared to -8.9% for the LED group (p < 0.05). Significantly greater reductions in blood glucose (p < 0.05), cholesterol and LDL-C (p < 0.01 for both), and waist circumference (p≤ 0.05) were noted in VLED compared to those for LED diet. Short-term, rapid weight loss produced the desired ≥5% weight loss suggested to substantially reduce metabolic abnormalities associated with obesity, and to reduce health risks.     

Removal of Cd(II) ions from aqueous solution using a cation exchanger derived from banana stem

BACKGROUND: Environmental pollution and its abatement have attracted much attention for some time. The problem of removing pollutants from water and wastewater has grown along with rapid industrialization. Formaldehyde polymerized banana stem (FPBS) having sulphonic acid groups was investigated as an adsorbent for cadmium(II) removal from aqueous solutions. RESULTS: The outstanding function of the adsorbent was demonstrated at pH 9.0. The adsorption efficiency of FPBS was compared with BS and results showed that FPBS was two times more effective than BS for cadmium(II) removal. Maximum recoveries of 97.3 and 90.3% for 10 and 25 mg L^?1 initial concentrations were obtained at pH 9.0. Kinetic studies revealed that adsorption occurred in two stages: external mass transport in the first stage and intra‐particular diffusion in the second stage. Adsorption was found to be rapid and equilibrium was attained in 60 min. Among the various desorbing agents tested, 99.2% cadmium recovery was achieved with 0.1 mol L^?1 HCl. CONCLUSIONS: The uptake efficiency of cadmium(II) by FPBS was determined. Repeated adsorption‐desorption study showed that FPBS can be used as an adsorbent for the removal and recovery of Cd(II) from aqueous solutions. Copyright © 2012 Society of Chemical Industry     

A novel role for murine IL-4 in vivo: induction of MUC5AC gene expression and mucin hypersecretion

Mucus hypersecretion and plugging of lower respiratory tract airways contributes to the morbidity and mortality associated with asthma. Interleukin (IL)-4 plays a putative role in some forms of asthma. Thus, transgenic mice that overexpress murine IL-4 selectively within the lung were used to study the effect of IL-4 on mucus glycoprotein gene expression and mucin release. Histologic examination of lung sections from IL-4 mice revealed that nonciliated epithelial cells from conducting airways were hypertrophic, due at least in part to the accumulation of mucus glycoprotein. The cytoplasm of these cells stained positively for glycoproteins using mucicarmine, alcian blue (AB), and periodic acid-Schiff (PAS). Ciliated cells were also enlarged but did not show any mucin-specific staining. Inclusion granules typically found in nonciliated (Clara) cells of control mice were absent in the IL-4 transgenic mice. Northern blot analysis of total RNA from lung tissue revealed that the expression of the MUC5AC, but not MUC2, mucin gene was distinctly upgraded in IL-4 transgenic mice compared to transgene-negative controls. In addition, a 5- to 10-fold increase in AB- and PAS-positive material was found in lavage fluid from IL-4 overexpressing mice compared to transgene-negative controls. Thus, the overexpression of IL-4 locally within the lung enhances mucus glycoprotein synthesis by altering gene expression, results in the accumulation of mucus glycoprotein in nonciliated epithelial cells, and induces the release of mucus into the airway lumen. We therefore hypothesize that the overproduction of mucus seen in some patients with asthma may be a direct result of the action of IL-4 within the inflamed lung.     

Parents'' sung performances for infants

We have cloned an unique gene encoding the heavy chain of a type II myosin in the fission yeast, Schizosaccharomyces pombe. The myo2+ gene encodes a protein of 1526 amino acids with a predicted molecular weight of 177 kDa and containing consensus binding motifs for both essential and regulatory light chains. The S. pombe myo2+ head domain is 45% identical to myosin IIs from Saccharomyces cerevisiae and Homo sapiens and 40% identical to Drosophila melanogaster Structurally, myo2+ most closely resembles budding yeast MYO1, the tails of both myosin IIs containing a number of proline residues that are predicted to substantially disrupt the ability of these myosins to form coiled coils. The myo2+ gene is located on chromosome III, 8.3 map units from ade6+. Deletion of approximately 70% of the coding sequence of myo2+ is lethal but myo2delta spores can acquire a suppressor mutation that allows them to form viable microcolonies consisting of filaments of branched cells with aberrant septa. Overexpression of myo2+ results in the inhibition of cytokinesis; cells become elongated and multinucleate and fail to assemble a functional cytokinetic actin ring and are either aseptate or form aberrant septa. These results suggest that a contractile actin-myosin based cytokinetic mechanism appeared early in the evolution of eukaryotic cells and further emphasise the utility of fission yeast as a model organism in which to study the molecular and cellular basis of cytokinesis.     

Resolution of abnormal MR signal intensity in patients with stress fractures of the femoral neck

OBJECTIVE: The purpose of this study was to describe the natural evolution of abnormal MR signal intensity after the diagnosis of a stress fracture of the femoral neck and to ascertain the time to resolution of that abnormal signal intensity. SUBJECTS AND METHODS: Ten patients who had been previously diagnosed with stress fractures of the femoral neck after positive MR scans of the hip were examined with MR imaging at regular intervals. In each patient T1-weighted and short inversion time inversion recovery (STIR) sequences were obtained until the abnormally bright, diffuse MR signal intensity (representing edema) disappeared from the STIR images. Time to resolution was correlated with each patient's age and presence or absence of a fatigue line on MR imaging. Statistical analysis was done using Fisher's exact test. RESULTS: Edema resolved in seven patients within 3 months of initial diagnosis, in two patients within 6 months, and in the remaining patient within 12 months. We found no statistically significant correlation between time to resolution and patient age or the presence of a fatigue line on MR imaging. Residual sclerosis occurred in five patients, all of whom had a fatigue line. Two of these patients developed bright T1 signal (fatty marrow conversion) around the area of sclerosis. In the remaining three patients, STIR images revealed a brightened fatigue line, which we presumed was caused by granulation tissue. CONCLUSION: In this study, 90% of patients showed resolution of abnormal MR signal intensity on STIR imaging within 6 months of the initial diagnosis of stress fracture of the femoral neck. Such data may prove helpful in examining patients with recurrent symptoms who undergo repeated MR scanning. When an abnormally bright, diffuse MR signal intensity on STIR imaging is seen more than 6 months after an original injury, such abnormal signal intensity is likely to represent new injury.     

In vitro antineoplastic activity of a novel lanthionine-containing peptide

It has been a long-term goal to discover peptides that can kill tumor cells while sparing normal tissues. Lan-7 is a novel, chemically stable peptide structurally related to somatostatin that contains a lanthionine bridge between the two cysteines in the peptide; TT-232 is a less stable analogue containing a disulfide bridge. The antitumor activity of Lan-7 was examined, relative to that of TT-232 and the clinically used analogue octreotide, against a panel of malignant human tumor cell lines and normal human hematopoietic precursors. Lan-7 was cytotoxic to all four tumor cell lines, with IC50 values ranging over a 2-fold range from 16 to 36 microM. The potency of Lan-7 was comparable to that of TT-232, and both of these agents were two to three times more potent than octreotide. At concentrations that were highly cytotoxic to tumor cells, Lan-7 produced no significant toxicity to normal human hematopoietic precursors. Lan-7 induced apoptosis in human ovarian carcinoma 2008 cells over the same concentration range at which it produced cytotoxicity, but it did so without activating G1, S, or G2 checkpoints, given that it produced no perturbation of cell cycle phase distribution. Cells engineered to overexpress P-glycoprotein were not more resistant to Lan-7 than isogeneic cells not expressing the mdr1 gene. These results make Lan-7 of interest as a potential cancer chemotherapeutic agent.