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Abstract: This paper examines the problem of harvest capacity planning at a tactical level. Annual capacity planning allows planners to determine the number of contractors to hire per period throughout [...]

In this paper, we present a mathematical model to plan logistics activities in a forest products supply chain. In particular, a mixed-integer linear program is developed to maximize the total profit of the value chain, involving decisions related to the volumes of wood to harvest and to keep in stock, as well as the quantities to deliver to each business unit to meet market demand. The model also includes different constraints concerning fibre freshness across the network (forest, sawmills, and paper mill), as this has an effect on operation costs and supply decisions. Various scenarios based on the demand variation, price fluctuations, and wood aging levels are tested, followed by a sensitivity analysis. Results show that price and demand variations as well as fibre freshness are important criteria to consider in the procurement and production planning for increasing the forest supply chain benefits. The scenarios analysed also confirm the usefulness of the model in guiding companies to make adequate planning decisions according to their business environment. [ABSTRACT FROM AUTHOR]

Ultraviolet-assisted three-dimensional (3D) printing (UV-3DP) was used to manufacture photopolymer-based microdevices with 3D self-supported and freeform features. The UV-3DP technique consists of the robotized deposition of extruded filaments, which are rapidly photopolymerized under UV illumination during the deposition process. This paper systematically studies the processing parameters of the UV-3DP technique using two photo-curable polymers and their associated nanocomposite materials. The main processing parameters including materials' rheological behavior, deposition speed and extrusion pressure, and UV illumination conditions were thoroughly investigated. A processing map was then defined in order to help choosing the proper parameters for the UV-3DP of microstructures with various geometries. Compared to self-supported features, the accurate fabrication of 3D freeform structures was found to take place in a narrower processing region since a higher rigidity of the extruded filament was required for structural stability. Finally, various 3D self-supported and freeform microstructures with high potential in micro electromechanical systems, micro-systems and organic electronics were fabricated to show the capability of the technique. [ABSTRACT FROM AUTHOR]

Context: Even though red blood cells (RBCs) are lifesaving in neonatal intensive care, transfusing older RBCs may result in higher rates of organ dysfunction, nosocomial infection, and length of hospital stay.Objective: To determine if RBCs stored for 7 days or less compared with usual standards decreased rates of major nosocomial infection and organ dysfunction in neonatal intensive care unit patients requiring at least 1 RBC transfusion.Design, Setting, and Participants: Double-blind, randomized controlled trial in 377 premature infants with birth weights less than 1250 g admitted to 6 Canadian tertiary neonatal intensive care units between May 2006 and June 2011.Intervention: Patients were randomly assigned to receive transfusion of RBCs stored 7 days or less (n = 188) vs standard-issue RBCs in accordance with standard blood bank practice (n = 189).Main Outcome Measures: The primary outcome was a composite measure of major neonatal morbidities, including necrotizing enterocolitis, retinopathy of prematurity, bronchopulmonary dysplasia, and intraventricular hemorrhage, as well as death. The primary outcome was measured within the entire period of neonatal intensive care unit stay up to 90 days after randomization. The rate of nosocomial infection was a secondary outcome.Results: The mean age of transfused blood was 5.1 (SD, 2.0) days in the fresh RBC group and 14.6 (SD, 8.3) days in the standard group. Among neonates in the fresh RBC group, 99 (52.7%) had the primary outcome compared with 100 (52.9%) in the standard RBC group (relative risk, 1.00; 95% CI, 0.82-1.21). The rate of clinically suspected infection in the fresh RBC group was 77.7% (n = 146) compared with 77.2% (n = 146) in the standard RBC group (relative risk, 1.01; 95% CI, 0.90-1.12), and the rate of positive cultures was 67.5% (n = 127) in the fresh RBC group compared with 64.0% (n = 121) in the standard RBC group (relative risk, 1.06; 95% CI, 0.91-1.22).Conclusion: In this trial, the use of fresh RBCs compared with standard blood bank practice did not improve outcomes in premature, very low-birth-weight infants requiring a transfusion.Trial Registration: clinicaltrials.gov Identifier: NCT00326924; Current Controlled Trials Identifier: ISRCTN65939658. [ABSTRACT FROM AUTHOR]

We report on the fabrication and transport properties of single-walled carbon nanotube (SWCNT)/polyurethane (PU) nanocomposite microfiber-based field effect transistors (FETs). UV-assisted direct-writing technology was used, and microfibers consisting of cylindrical micro-rods, having different diameters and various SWCNT loads, were fabricated directly onto SiO2/Si substrates in a FET scheme. The room temperature dc electrical conductivities of these microfibers were shown to increase with respect to the SWCNT concentrations in the nanocomposite, and were about ten orders of magnitude higher than that of the pure polyurethane, when the SWCNT load ranged from 0.1 to 2.5 wt% only. Our results show that for SWCNT loads ≤1.5 wt%, all the microfibers behave as a FET with p-type transport. The resulting FET exhibited excellent performance, with an Ion=Ioff ratio of 105 and a maximum on-state current (Ion) exceeding 70 μA. Correlations between the FET performance, SWCNTs concentration, and the microfiber diameters are also discussed. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To study the association between current or previous weight status and school performance among children and young adolescents of Hat Yai municipality, southern Thailand. DESIGN: Cross-sectional and longitudinal study SETTING: Primary and secondary schools of Hat Yai municipality, southern Thailand. SUBJECTS: 1207 grades 3-6 and 587 grades 7-9 students. MEASUREMENTS: Body mass index (BMI, kg/m²) calculated from weight and height measurement of subjects in 1992 and 1994; parental education level and occupation, and monthly income, by questionnaire performed in 1992; gradepoint-average (GPA) and grades of mathematics and Thai language from the school records of final examinations in 1994. RESULTS: Overweight subjects (BMI value > 85th percentile of the NHANES-I data for age and gender) in grades 7-9 had a mean GPA 0.20 point (95% confidence internal (CI)= 0.04, 0.37) lower than that of the normal weight children after controlling for gender, age, school and grade. They were twice more likely to have Iow grades (lower than 2 on the scales of 0-4) of mathematics and Thai language than normal weight children. There were no associations between GPA or individual subject grades and previous BMI status in 1992. Children in grades 7-9 who became overweight over the two years, had a mean GPA of 0.48 point lower than those who did not become overweight (95% CI = 0.12, 0.84). In grades 3-6 subjects, however, becoming overweight had no effect on GPA and individual subject scores. CONCLUSIONS: Our study showed that being overweight and becoming overweight during adolescence (grades 7 -9) was associated with poor school performance, whereas such an association did not exist in children (grades 3-6). [ABSTRACT FROM AUTHOR]

Tritiated sertraline, a radiolabeled form of a potent and selective inhibitor of serotonin uptake, was found to bind with high affinity to rat whole brain membranes. Characterization studies showed that [H] sertraline binding occurred at a single site with the following parameters: K 0.57 nM, B 821 fmol/mg protein, n 1.06. This binding was reversible; the dissociation constant calculated from kinetic measurements ( K 0.81 nM) agreed with that determined by saturation binding experiments. [H] Sertraline binding in the presence of serotonin, paroxetine, fluoxetine or imipramine suggested competitive inhibition of binding (large increase in K with little change in B). The rank order of potency of inhibition of [H] sertraline binding was similar to that of inhibition of serotonin uptake for known uptake inhibitors and the 1-amino-4-phenyltetralin uptake blockers. A marked decrease in ex vivo [H] sertraline binding in the brain of rats 7 days after treatment with p-chloroamphetamine was consistent with the loss of serotonin uptake sites induced by this agent. The results of our study indicated that [H] sertraline labels serotonin uptake sites in rat brain. [ABSTRACT FROM AUTHOR]