Production setup-sequencing and lot-sizing at an animal nutrition plant through <Emphasis Type="SmallCaps">atsp</Emphasis> subtour elimination and patching

This paper considers the usefulness of a production lot sizing and scheduling model at an animal nutrition plant with sequence-dependent setup times. The model covers multiple periods and is based on the asymmetric travelling salesman problem (atsp). It is applied initially to the case where the setup state is zeroed between periods, and then revised to model the carryover of the setup state from one period to the next. An iterative solution procedure based on subtour elimination is applied, and then enhanced by the inclusion of a subtour patching procedure. Case-based tests with actual plant data show that the subtour elimination is practicably fast where the setup state is zeroed between periods, but needs the patching procedure when the setup state is preserved, as is the situation at the plant. In this latter case, the subtour elimination and patching can be very fast, showing the method’s viability for operational lot sizing and sequencing in animal nutrition plants of the kind studied. Tests on perturbed plant data show that further algorithmic development is needed to tackle certain challenging variants found in other plants.     

Three-dimensional container loading models with cargo stability and load bearing constraints

Mathematical models for the problem of loading rectangular boxes into containers, trucks or railway cars have been proposed in the literature, however, there is a lack of studies which consider realistic constraints that often arise in practice. In this paper, we present mixed integer linear programming models for the container loading problem that consider the vertical and horizontal stability of the cargo and the load bearing strength of the cargo (including fragility). The models can also be used for loading rectangular boxes on pallets where the boxes do not need to be arranged in horizontal layers on the pallet. A comprehensive performance analysis using optimization software with 100s of randomly generated instances is presented. The computational results validate the models and show that they are able to handle only problems of a moderate size. However, these models might be useful to motivate future research exploring other solution approaches to solve this problem, such as decomposition methods, relaxation methods, heuristics, among others.     

Information centric networking over SDN and OpenFlow: Architectural aspects and experiments on the OFELIA testbed

Information Centric Networking (ICN) is a new networking paradigm in which the network provides users with content instead of communication channels between hosts. Software Defined Networking (SDN) is an approach that promises to enable the continuous evolution of networking architectures. In this paper we propose and discuss solutions to support ICN by using SDN concepts. We focus on an ICN framework called CONET, which grounds its roots in the CCN/NDN architecture and can interwork with its implementation (CCNx). Although some details of our solution have been specifically designed for the CONET architecture, its general ideas and concepts are applicable to a class of recent ICN proposals, which follow the basic mode of operation of CCN/NDN. We approach the problem in two complementary ways. First we discuss a general and long term solution based on SDN concepts without taking into account specific limitations of SDN standards and equipment. Then we focus on an experiment to support ICN functionality over a large scale SDN testbed based on OpenFlow, developed in the context of the OFELIA European research project. The current OFELIA testbed is based on OpenFlow 1.0 equipment from a variety of vendors, therefore we had to design the experiment taking into account the features that are currently available on off-the-shelf OpenFlow equipment.     

Dexfentluramine in the treatment of juvenile obesity

BACKGROUND: The aim of this study was to investigate the potential of dexfenfluramine (dF) for reducing cardiovascular risk factors and improving compliance towards diet in a group of young patients hospitalized for essential obesity of high degree (BMI > or = 35). METHODS: 103 adolescents (mean age 15.4 +/- 0.2) participated in a nine-week randomized double-blind study of dF (15 mg bid) versus placebo. All patients received a VLCD (2,512 kJ/day = 600 kcal/day) for two months. In basal conditions, and after 30 and 60 days of treatment, anthropometric variables (height, weight, BMI, and W/H) and cardiovascular risk factors (blood glucose concentration, total cholesterol, HDL-cholesterol, triglycerides, systolic and diastolic blood pressure) were monitored. Modifications in hunger and satiety were also assessed. RESULTS: During the treatment period, both the dF group and the placebo group presented a similar pattern of weight loss (BMI = dF: 36.7 +/- 0.5 vs 32.5 +/- 0.4 vs 30.1 +/- 0.4; placebo: 37.0 +/- 0.6 vs 33.1 +/- 0.5 vs 30.8 +/- 0.5). No important side-effects were recorded in either group. Blood pressure and metabolic markers decreased significantly in both groups. Earlier reductions in total cholesterol and diastolic blood pressure in dF-treated subjects were the only significant differences observed as compared to the patients receiving placebo (day 30 = total cholesterol: 120 +/- 2 (dF) vs 132 +/- 3 (placebo) mg/dI; p < 0.005; diastolic blood pressure: 73 +/- 1 (dF) vs 77 +/- 1 (placebo) mmHg; p < 0.01). However, after 60 days, these values were similar in the two groups. As far as non-parametric data are concerned, dF determined a reduction in hunger and an increase in satiety in a significantly higher number of subjects than did the placebo, not only after 30 days of treatment (92.8% vs 55.3% and 92.8% vs 45.5%, respectively; p < 0.0001), but also after two months of treatment (97.8% vs 67.4% and 97.8% vs 45.8%, respectively; p < 0.0001). CONCLUSIONS: These findings demonstrate that dF represents a useful support in the treatment of juvenile obesity and might ensure a better individual compliance towards restrictive diets, particularly in the initial "critical" stages, in the absence of important side-effects.     

A Simple Analytical Framework for the Performance Evaluation of a Tree-Based Connection Rerouting Architecture in a UMTS Network

The enormous increase in wireless communications and the growing request for transmission bandwidth have led to the need to configure wireless access networks with cellular structures based on the use of micro- and pico-cells. Applying these structures means that handovers between neighboring cells are more frequent and therefore have to be carefully managed. A key issue in connection with this is the rerouting of the data flows directed to a user making a handover. In fact, the time interval needed to update all the routing tables in the crossover switches is critical because in this interval data have to be stored, and later forwarded once the route towards the new location has been determined. The paper considers a connectionless protocol, the Signaling Network Layer (SNL), which has been conceived for use in the Universal Mobile Telecommunication System (UMTS) context for connection rerouting purposes and is based on a tree-structured rerouting architecture. Through an analytical model based on a queueing network, its performance is analyzed in terms of the distribution of the rerouting delay. The proposed model is then applied to a case study to demonstrate its versatility and manageability and to get insight into the dimensioning of the rerouting architecture.     

The divergent homeobox gene PBX1 is expressed in the postnatal subventricular zone and interneurons of the olfactory bulb

In the mammalian brain, an important phase of neurogenesis occurs postnatally in the subventricular zone (SVZ). This region consists of a heterogeneous population of cells, some mitotically active, others postmitotic. A subset of mitotically active SVZ precursor cells gives rise to a population of neurons that migrates over a long distance to their final destination, the olfactory bulb. Other SVZ precursor cells continue to proliferate or undergo cell death. The combination of genes that regulates proliferation and cell fate determination of SVZ precursor cells remains to be identified. We have used the rat homolog of the human homeobox gene PBX1 in Northern analysis and in situ hybridization studies to determine the temporal and regional localization of PBX1 expression during embryonic and postnatal rat brain development. PBX1 is expressed embryonically in the telencephalon. In addition, it is expressed at high levels postnatally in the SVZ, in the migratory pathway to the olfactory bulb, and in the layers of the olfactory bulb that are the targets of these migratory neurons. Combining in situ hybridization for PBX1 with immunostaining for markers of cell proliferation (PCNA), postmitotic neurons (class III beta-tubulin), and glia (GFAP), we show that SVZ proliferating cells and their neuronal progeny express rat PBX1 mRNA, whereas glial cells do not express detectable levels of PBX1. The expression of PBX1 in SVZ precursor cells and postmitotic neurons suggests a role for PBX1 in the generation of olfactory bulb interneurons and in mammalian neurogenesis.     

A randomized, controlled trial of a 24-month course of interferon alfa 2b in patients with chronic hepatitis B who had hepatitis B virus DNA without hepatitis B e antigen in serum

Short-term interferon treatment of serum hepatitis B e antigen (HBeAg)-negative carriers with serum hepatitis B virus (HBV) DNA and histological features of chronic hepatitis B has been largely unsuccessful. In a pilot study of long-term treatment, 42 such patients were randomly assigned to 6 million units of interferon alfa 2b (IFN-alpha2b) three times per week for 24 consecutive months (n = 21, 4 with cirrhosis) or to no therapy (n = 21, 3 with cirrhosis). Five patients (24%) discontinued therapy because of treatment-related adverse reactions. Serum levels of alanine transaminase (ALT) became persistently normal and HBV DNA undetectable by dot-blot assay in 8 patients receiving interferon and in 2 untreated controls (38% vs. 10%; P = .03). Hepatitis flare-ups disappeared in 17 patients during therapy compared with 6 controls (81% vs. 29%; P < .001). During a median period of 22 months after interferon was stopped, 2 treated patients (10%) lost serum hepatitis B surface antigen (HBsAg) and seroconverted to antibodies to hepatitis B surface antigen (anti-HBs). Serum ALT remained persistently normal and HBV DNA undetectable by dot-blot assay in 6 initial responders and 1 initial nonresponder, compared with none of the 21 untreated controls (sustained response: 33% vs. 0; P < .001). Comparative analysis of pre- and posttreatment liver biopsies showed that mean Knodell scores dropped in the treated group (10.3 to 5.3; P = .01), but not in the untreated group (9.3 to 9.8; not significant). In conclusion, a 24-month course of treatment with 6 MU IFN-alpha2b was well tolerated by most patients, led to sustained suppression of HBV in one third, and attenuated hepatitis in 81% of patients.