Synthesis of Rice Straw Fiber Reinforced Natural Rubber Composite and Effects of Surface Treatment in its Mechanical Properties

In the last decade the use of natural fiber in reinforcement of composite materials is increased, because of growing environmental awareness. The main objective of present work is to study the mechanical properties of rice straw fiber reinforced natural rubber composites at different weight fractions (20%, 30%, 40%, 50% and 60%) of rice straw fiber under treated and non treated conditions. At first the fiber is treated with NaOH, and then composite is manufactured for both untreated and treated fiber. After the synthesis of rice straw fiber reinforced natural rubber composite, The effects of surface treatment in its mechanical properties are studied. Rice straw fiber reinforced natural rubber composites were manufactured according to ASTM standards using compression molding technique. The developed composites were then tested for their mechanical properties, tensile, tear, density, abrasion, hardness, compression, and water absorption properties. The standard test methods used is, ASTM-D638M for tensile properties

On the mechanical behaviour of PEEK and HA cranial implants under impact loading

The human head can be subjected to numerous impact loadings such as those produced by a fall or during sport activities. These accidents can result in skull fracture and in some complex cases, part of the skull may need to be replaced by a biomedical implant. Even when the skull is not damaged, such accidents can result in brain swelling treated by decompressive craniectomy. Usually, after recovery, the part of the skull that has been removed is replaced by a prosthesis. In such situations, a computational tool able to analyse the choice of prosthesis material depending on the patient's specific activity has the potential to be extremely useful for clinicians. The work proposed here focusses on the development and use of a numerical model for the analysis of cranial implants under impact conditions. In particular, two main biomaterials commonly employed for this kind of prosthesis are polyether-ether-ketone (PEEK) and macroporous hydroxyapatite (HA). In order to study the suitability of these implants, a finite element head model comprising scalp, skull, cerebral falx, cerebrospinal fluid and brain tissues, with a cranial implant replacing part of the skull has been developed from magnetic resonance imaging data. The human tissues and these two biocompatible materials have been independently studied and their constitutive models are provided here. A computational model of the human head under impact loading is then implemented and validated, and a numerical comparison of the mechanical impact response of PEEK and HA implants is presented. This comparison was carried out in terms of the effectiveness of both implants in ensuring structural integrity and preventing traumatic brain injury.The researchers of the University Carlos III are indebted to the Ministerio de Economía y Competitividad de España (Project DPI2014-57989-P) and Vicerrectorado de Política Científica UC3M (Project 2013-00219-002) for the financial support. A.J. acknowledges funding from the European Union's Seventh Framework Programme (FP7 2007–2013) ERC Grant Agreement No. 306587. MRI data were provided by the Human Connectome Project, WUMinn Consortium (Principal Investigators: David Van Essen and Kamil Ugurbil; 1U54MH091657) funded by the 16 NIH Institutes and Centers that support the NIH Blueprint for Neuroscience Research; and by the McDonnell Center for Systems Neuroscience at Washington University. Finally, we would like to thank Dr. S Barhli and Prof. J Marrow for valuable assistance with the X-ray tomography; the machine used was bought from EPSRC Grant EP/M02833X/1 “University of Oxford: experimental equipment upgrade”. Open Access funded by European Research Counci

UK Chiari 1 Study: protocol for a prospective, observational, multicentre study

INTRODUCTION: Chiari 1 malformation (CM1) is a structural abnormality of the hindbrain characterised by the descent of the cerebellar tonsils through the foramen magnum. The management of patients with CM1 remains contentious since there are currently no UK or international guidelines for clinicians. We therefore propose a collaborative, prospective, multicentre study on the investigation, management and outcome of CM1 in the UK: the UK Chiari 1 Study (UKC1S). Our primary objective is to determine the health-related quality of life (HRQoL) in patients with a new diagnosis of CM1 managed either conservatively or surgically at 12 months of follow-up. We also aim to: (A) determine HRQoL 12 months following surgery; (B) measure complications 12 months following surgery; (C) determine the natural history of patients with CM1 treated conservatively without surgery; (D) determine the radiological correlates of presenting symptoms, signs and outcomes; and (E) determine the scope and variation within UK practice in referral patterns, patient pathways, investigations and surgical decisions. METHODS AND ANALYSIS: The UKC1S will be a prospective, multicentre and observational study that will follow the British Neurosurgical Trainee Research Collaborative model of collaborative research. Patients will be recruited after attending their first neurosurgical outpatient clinic appointment. Follow-up data will be collected from all patients at 12 months from baseline regardless of whether they are treated surgically or not. A further 12-month postoperative follow-up timepoint will be added for patients treated with decompressive surgery. The study is expected to last three years. ETHICS AND DISSEMINATION: The UKC1S received a favourable ethical opinion from the East Midlands Leicester South Research Ethics Committee (REC reference: 20/EM/0053; IRAS 269739) and the Health Research Authority. The results of the study will be published in peer-reviewed medical journals, presented at scientific conferences, shared with collaborating sites and shared with participant patients if they so wish

A linear programming-based method for job shop scheduling

We present a decomposition heuristic for a large class of job shop scheduling problems. This heuristic utilizes information from the linear programming formulation of the associated optimal timing problem to solve subproblems, can be used for any objective function whose associated optimal timing problem can be expressed as a linear program (LP), and is particularly effective for objectives that include a component that is a function of individual operation completion times. Using the proposed heuristic framework, we address job shop scheduling problems with a variety of objectives where intermediate holding costs need to be explicitly considered. In computational testing, we demonstrate the performance of our proposed solution approach

Conspecific chemical cues facilitate mate trailing by invasive Argentine black and white tegus

Squamate reptiles (snakes and lizards) rely on chemical cues from conspecifics to search the environment for potential mates. How such cues are used by invasive species to facilitate reproduction, especially seasonally, is a key question that can inform management practices. The Argentine black and white tegu (Salvator merianae) is an invasive reptile species in south Florida threatening native fauna in biodiverse regions such as Everglades National Park. While some information exists on the reproductive ecology of this species in its native range in South America, the chemical ecology of S. merianae is unclear especially in its invasive range. By testing both male (n = 7) and female (n = 7) tegus in a Y-maze apparatus, we assessed if either sex follows chemical trails left by conspecifics and if behaviors were sex- or season-specific. We conducted three types of trials where conspecifics created odor trails: Male-only (male scent only in base and one arm of Y), Female-only, and Male vs. female. Males did not preferentially follow scent trails from either sex, but they did differentially investigate conspecific scent from both sexes. Seasonally, males showed increased rates of chemosensory sampling (rates of tongue-flicking) during the spring (breeding season; March-May) compared to fall (non-breeding season; September-November). Males also had reduced turning and pausing behavior while trailing in the spring. Female tegus exhibited stronger conspecific trailing abilities than males, following both male and female scent trails, and they explored the maze less before making an arm choice. Females also investigated the scent trails intensely compared to males (more passes in scented arms, more time with scent trails). Our results demonstrate for the first time that females of an invasive reptile species can follow conspecific scent trails. Given the strong female responses to odor, sex-specific targeting of tegus via application of a conspecific chemical cue in traps could enhance removal rates of females during the breeding season

Applications of microfluidics for molecular diagnostics

journal articleDiagnostic assays implemented in microfluidic devices have developed rapidly over the past decade and are expected to become commonplace in the next few years. Hundreds of microfluidics-based approaches towards clinical diagnostics and pathogen detection have been reported with a general theme of rapid and customizable assays that are potentially cost-effective. This chapter reviews microfluidics in molecular diagnostics based on application areas with a concise review of microfluidics in general. Basic principles of microfabrication are briefly reviewed and the transition to polymer fabricated devices is discussed. Most current microfluidic diagnostic devices are designed to target a single disease, such as a given cancer or a variety of pathogens, and there will likely be a large market for these focused devices; however, the future of molecular diagnostics lies in highly multiplexed microfluidic devices that can screen for potentially hundreds of diseases simultaneously

Black and White group photo

Black and white photo of 5 people, 4 men and 1 woman