A simplified technique for shakedown limit load determination

In this paper, a simplified technique is presented to determine the shakedown limit load of a structure using the finite element method. The simplified technique determines the shakedown limit load without performing lengthy time consuming full elastic-plastic cyclic loading simulations or conventional iterative elastic techniques. Instead, the shakedown limit load is determined by performing two analyses namely: an elastic analysis and an elastic-plastic analysis. By extracting the results of the two analyses, the shakedown limit load is determined through the calculation of the residual stresses developed within the structure. The simplified technique is applied and verified using two bench mark shakedown problems namely: the two-bar structure subjected to constant axial force and cyclic thermal loading, and the Bree cylinder subjected to constant internal pressure and cyclic high temperature variation across its wall. The results of the simplified technique showed very good correlation with the, analytically determined, Bree diagrams of both structures. In order to gain confidence in the simplified technique, the shakedown limit loads output by the simplified technique are used to perform full elastic-plastic cyclic loading simulations to check for shakedown behavior of both structures.     

Adjuvant treatment of high-risk breast cancer using multicycle high-dose chemotherapy and filgrastim-mobilized peripheral blood progenitor cells

Women with primary breast cancer associated with extensive axillary node involvement or large primary tumors have a very poor prognosis despite treatment with standard-dose adjuvant chemotherapy. In an attempt to improve the outlook of these patients, we investigated the safety and feasibility of delivering three cycles of high-dose epirubicin and cyclophosphamide supported with filgrastim-mobilized peripheral blood progenitor cells (PBPC). Fifteen previously untreated women, median age 50 (range, 30-58) years, with poor prognosis early stage breast cancer received filgrastim (12 microgram/kg daily for 6 days) prior to chemotherapy to mobilize progenitor cells. Patients were then given three cycles of epirubicin (200 mg/m2) and cyclophosphamide (4 g/m2) at planned 28-day intervals, each followed by infusion of one third of the PBPC collected and daily administration of filgrastim (5 microgram/kg s.c.). Three leukaphereses collected a median of 114.9 (range, 22.7-273.5) x 10(4) granulocyte-macrophage-colony-forming cells/kg body weight. Hemopoietic recovery was rapid after each cycle, and there was no correlation between the rate of recovery and the number of granulocyte-macrophage-colony-forming cells infused. There was a small but significant progressive delay in recovery from hematological and nonhematological toxicities across the three cycles. Left ventricular ejection fraction fell to below 50% in eight (53%) patients, but none developed congestive cardiac failure. Two patients did not complete three cycles because of insufficient PBPC for a third cycle (n = 1) and 2-mercaptoethane sodium sulfonate- related drug reaction during the second cycle (n = 1). There were no deaths during the study or during the follow-up period (median, 70 weeks; range, 50-85 weeks), and no late toxicities occurred. Therefore, we concluded that the delivery of multiple cycles of nonmyeloablative, dose-intensive chemotherapy supported by PBPC and filgrastim is safe, and may be widely applicable to a variety of common chemosensitive cancers with a poor prognosis. The efficacy of three cycles of high-dose epirubicin and cyclophosphamide is to be compared with standard-dose chemotherapy in a randomized trial in patients with high-risk, operable stage II and III breast cancer.     

Perceived Clarity of Individual Job Objectives and of Group Mission as Correlates of Organizational Morale

Based on experiments showing reactions to induced frustration, it was assumed that lack of clarity on the part of an employee regarding his own job or the overall mission of his location will have significant negative consequences. It was thus hypothesized that: (1) lack of clarity of individual job objectives would be negatively related to job satisfaction and overall satisfaction, and (2) that lack of clarity of location of mission would be negatively related to job satisfaction, overall satisfaction and perceptions of organizational cohesiveness (both intra- and inter-departmental). All six predicted relationships were obtained. Implications of these results, including those for organizational communication and personnel administration, are discussed.     

Paper Strengthening by Starch Xanthate-Alkyl Diepoxide Adducts

The reaction between starch xanthate and alkyl diepoxide formed gels in concentrated solution (6–8%) or turbid suspensions in dilute solution (0.1–1,0%); the gelling varied with the nature of the epoxide. The gel or suspension was dispersed and added to wood pulp suspension and therefrom paper products of improved strength characteristics were formed. Also the reaction was conducted in the presence of paper furnish. Handsheets made from furnish containing a 2.5% additive level based on fiber content had burst, folding endurance, and wet and dry breaking length values 1.6, 4.6, 4.2 and 1.4 times, respectively, those of control papers. Improvement in properties was somewhat independent of the xanthate's degree of substitution but dependent on the reaction time (either separate from or in presence of fiber) and the order of addition of epoxide and xanthate.     

Tailoring Additively Manufactured Titanium Implants for Short-Time Pediatric Implantations with Enhanced Bactericidal Activity

Paediatric titanium (Ti) implants are used for the short-term fixation of fractures, after which they are removed. However, bone overgrowth on the implant surface can complicate their removal. The current Ti implants research focuses on improving their osseointegration and antibacterial properties for long-term use while overlooking the requirements of temporary implants. This paper presents the engineering of additively manufactured Ti implants with antibacterial properties and prevention of bone cell overgrowth. 3D-printed implants were fabricated followed by electrochemical anodization to generate vertically aligned titania nanotubes (TNTs) on the surface with specific diameters (∼100 nm) to reduce cell attachment and proliferation. To achieve enhanced antibacterial performance, TNTs were coated with gallium nitrate as antibacterial agent. The physicochemical characteristics of these implants assessed by the attachment, growth and viability of osteoblastic MG-63 cells showed significantly reduced cell attachment and proliferation, confirming the ability of TNTs surface to avoid cell overgrowth. Gallium coated TNTs showed strong antibacterial activity against S. aureus and P. aeruginosa with reduced bacterial attachment and high rates of bacterial death. Thus a new approach for the engineering of temporary Ti implants with enhanced bactericidal properties with reduced bone cell attachment is demonstrated as a new strategy toward a new generation of short-term implants in paediatrics.     

CFD modeling to predict diffused date syrup yield and quality from sugar production process

In this study, diffusion process of sugar from date is modeled using a commercial computational fluids dynamics (CFD) code FLUENT 6.3.23 (Fluent Inc., USA). A two phases CFD model was developed using an Eulerian–Eulerian approach to calculate the date volume fraction transferred during time from date phase to water phase. The diffusion process was studied as function of three date varieties (Manakher, Lemsi and Alligue), three speeds of agitation (0, 50 and 100 rpm) and three date/water ratio (0.25, 0.50 and 0.75). The results revealed that, for mass transfer, the numerical data were in good agreement with the experimental data indicating the R² of 0.84. Using a Lemsi date variety, the optimal condition of diffusion were 50 rpm and 0.75 for speed of agitation and date/water ratio respectively.     

Design of an optimized traffic-aware routing algorithm using integer linear programming for software-defined networking

The number of internet users and connected devices has dramatically expanded due to the recent technological boom and the benefits that the internet of things offers to ease our lives. Network scheduling, quality of service, resource allocation, and security issues are now being addressed via software-defined networking (SDN). SDN has several benefits over traditional networks, including global centralized control, managing network traffic, and separating the forwarding and control plane. The work done in this paper aims to design and implement a traffic-aware routing framework based on routing optimization presented as an integer linear programming (ILP) to improve heterogeneous traffic flows' quality of service (QoS) in a simulated SDN environment. With the knowledge that the routing problem is a nondeterministic polynomial-time-hard problem, the proposed scheme aims to decrease the computational routing time to make the ILP-based routing system more suitable for real-time processing. The simulation results illustrate that the proposed framework reduces the computational time by 23% and 49% for Abilene and Goodnet topology, respectively. Additionally, with 1000 flows in the network, the suggested scheme reduces the number of network flows that violate the QoS by 9% and 22% (with Abilene topology) and 16% and 51% (with Goodnet topology) as compared to the existing shortest path delay and sway methods, respectively.     

The Polarographic Behaviour of Some Arylhydrazono Azoles

Inspection of the polarographic behaviour of the phenylhydrazones of a variety of heterocyclic azoles having an adjacent functional group indicated that these compounds, unlike typical phenylhydrazones, are reducible in a 4-electron wave in both acidic as well as in alkaline media. A mechanism to explain the electrode processes is proposed.