bluuebunny/crossref_metadata_2025_split huggingface dataset:
Miniaturized Planar Sensor Development
Authors: Azmi Aizat , Abdul Rahim Ruzairi , Song Chee Pei , Mohammad Din Shahrulnizahani , Ayob Nor Muzakkir Nor , Ling Leow Pei 
Published: August 2014

This paper describes the process of developing a miniature device with planar sensors utilizing electrical capacitance measurement. The project investigates the feasibility and characterization of a miniaturized planar sensor integrated on a polydimethylsiloxane (PDMS) chamber. A 16-planar-electrodes array, with each dimension of the electrode, 4 mm × 2 mm (length × width) was fabricated using a printed circuit board (PCB) technology due to its low cost advantage. The measurement chamber for the sensing area was fabricated using PDMS. The PDMS chamber was bonded on the PCB with a semi cured PDMS to create a round sensing area for sample loading. The mould to develop the PDMS chamber was designed using AutoCAD 2010 and was fabricated using a 3D printer. Capacitance measurement of the planar electrodes was carried out using water as the sample and was validated using a theoretical calculation. Experimental result shows that the distance of the measured electrodes is inversely proportional to the capacitance value. The range of the measured capacitances of the measurement varies from 10 pF to 20 pF. The result shows that the planar sensors are able to provide capacitance measurement within the miniaturized platform where the measured capacitance showed good agreement with the theoretical calculation.
Rigid and Conductive Dual Nanoprobe for Single Cell Analysis
Authors: Mat Sulaiman Abdul Hafiz , Ahmad Mohd Ridzuan 
Published: August 2014

Electrical property characterization of a single cell can be used to infer about its physiological condition, e.g. cell viability. Due to that, a dual nanoprobe-microfluidic system for electrical properties measurement of single cells has been proposed. This paper is concerned about the mechanical and electrical characterizations of the dual nanoprobe. Electrical and mechanical characterizations were conducted to measure the resistance and the strength of the dual nanoprobe for five different metals i.e. Aluminium, Copper, Silver, Tungsten, and Zinc using finite element approach. From the findings, Tungsten’s nanoprobe has the highest strength while the resistance values for the five materials are not significantly different. Therefore, Tungsten is selected as the most recommended metal for the dual nanoprobe. We also performed single cell electrical measurement to test the functionality of the sensor. This work provides general information of the nanoprobe which can be used as a framework in other applications involving Nano devices i.e. cell surgery and drug delivery.
Simulation of Single Cell Trapping Via Hydrodynamic Manipulation
Authors: Ahmad Khalili Amelia , Mohd Basri Mohd Ariffanan , Ahmad Mohd Ridzuan 
Published: August 2014

Microfluidic devices are important for the single cell analysis such as cell mechanical and electrical characterization. Single cell characterization could be related to many significant applications including early disease diagnosis. However to perform the single cell manipulation, firstly a single cell have to be isolated and a platform for the cell manipulation have to be provided. One of the methods to trap a single cell is by using hydrodynamic trapping in the microfluidic channel. This study provides a finite element model for single cell trapping for a yeast cell model. The objectives of the simulations are to obtain the appropriate channels’ geometry and optimized ratio of the fluid’s inlet and suction flow rate to trap a single yeast cell. Trap channel was designed to trap a 5μm yeast cell with a suction hole placed in the end of the trap channel. Design geometry and the ratio of fluid flow rates for the cell trapping model were studied using the hydrodynamic resistance concept. The analysis was carried out using numerical solutions from the finite element ABAQUS-FEA software. Using the cell trapping model, a single yeast cell able to be trapped into the trap channel with optimized channel’s suction hole’s geometry and appropriate fluid’s inlet and suction flow rate ratio. The appropriate QTrap/QMain ratio to perform cell trapping using hydrodynamic resistance concept is the ratio value above 1. A 5 μm yeast cell model able to be trap inside a trap channel with the height, width and length of 7 μm by manipulating the suction hole’s flow rate of 1.5 and 2.0 μm of height, 7 and 3 μm of length and width, respectively which situated at the centre edge of the trap channel.
Preparation and Characterization of Graphene Membrane Electrode Assembly
Authors: Aziz Madzlan , Abdul Halim Farah Syuhada , Jaafar Juhana 
Published: August 2014

Fuel cell has been of great demand as power sources for electronic devices. However this has been delayed by the deficiency of catalyst material properties. The aim of this research is to design and synthesis graphene membrane electrode assembly (MEA) as catalyst support in direct methanol fuel cell (DMFC). Graphene was produced from pure graphite powder using chemical reduction method of graphene oxide aqueous solution with a reducing agent. The modified membrane electrode assembly of graphene sulfonated poly (ether ether ketone) (SPEEK) was fabricated for DMFC testing. After the reduction process, the FTIR spectrum showed the disappearance of the carbonyl group of graphene oxide. XRD spectrum showed a sharp peak at 2θ = 26.4o whichcan be assigned as 002 indexed peak with hexagonal crystal structure. The morphology of graphene observed is a uniform multi layer with crumple flakes and the product has conductivity of as high as 1.36 x 104 S/m. The characteristic of the synthesized graphene membrane electrode assembly suggest potential application in direct methanol fuel cell.
γ-Ray Pre-Irradiated Grafting of Polytetrafluoroethylene Film Membrane
Authors: Idris Alamin , Rahmanian Nejat 
Published: August 2014

The changes induced by γ-ray pre-irradiated grafting of polytetrafluoroethylene (PTFE) with alkalo-amines such as Monoethanolamine (MEA), Diethanolamine (DEA) and Methyldiethanolamine (MDEA) solvents were investigated. Samples of the commercially available fluoropolymer, i.e. PTFE film membranes were irradiated with 60Co source γ-radiation with absorbed doses of 30 to 90 kGy. Effects of the grafting conditions of the amines onto the pre-irradiated PTFE, such as grafting time, reaction temperature and pre-irradiation doses on the resulting grafting yield are reported. The grafted PTFE was characterized by the FT-IR spectroscopy and FESEM.The gravimeteric analysis showed that the maximum grafting yield obtained is 2.9% for the 30 kGy irradiated MDEA grafted PTFE (MDEA-g-PTFE) at 10 min grafting time. However, at 60 min grafting time the maximum grafting yield reduced to 1.05% for the same sample. Consequently, therefore, for the low dose γ-ray pre-irradiated samples, the effects of applied dose and grafting time were found to be remarkably insignificant.
Preparation and Characterization of PVDF-TiO2 Composite Membranes Blended with Different Mw of PVP for Oily Wastewater Treatment using Submerged Membrane System
Authors: Ong C. S. , Lau W. J. , Goh P. S. , Ismail A. F. Ismail 
Published: August 2014

Polyvinylidene fluoride (PVDF) hollow fiber ultrafiltration (UF) membranes consisted of TiO2 and different molecular weight (Mw) of polyvinylpyrrolidone (PVP) (i.e. 10, 24, 40 and 360 kDa) were prepared to treat synthesized oily wastewater. The membrane performances were characterized in terms of pure water flux, permeate flux and oil rejection while the membrane morphological properties were studied using SEM and AFM. PVDF-TiO2 composite membrane prepared from PVP40k was found as the optimum membrane due to its high flux and high rejection during filtration process, recording 45 L/m2.h and 80% respectively, when tested using 250 ppm oily solution under submerged condition. The experimental results demonstrated that with increasing Mw of PVP, PVDF-TiO2 membrane had higher protein rejection, smaller porosity and smoother surface layer. With increasing oil concentration from 250 to 1000 ppm, the permeate flux of the PVDF-PVP40k was obviously decreased while the oil rejection was gradually increased due to the additional selective layer formed on the membrane surface. Based on the findings, the PVDF-TiO2 membrane with PVP40k can be considered as a potential membrane for oily wastewater industry due to the high permeate flux and oil rejection.
Separability of embedded surfaces in 3-manifolds
Authors: Przytycki Piotr , Wise Daniel T. 
Published: August 2014

AbstractWe prove that if$\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}S$is a properly embedded$\pi _1$-injective surface in a compact 3-manifold$M$, then$\pi _1S$is separable in$\pi _1M$.
The real Chevalley involution
Authors: Adams Jeffrey 
Published: August 2014

AbstractThe Chevalley involution of a connected, reductive algebraic group over an algebraically closed field takes every semisimple element to a conjugate of its inverse, and this involution is unique up to conjugacy. In the case of the reals we prove the existence of a real Chevalley involution, which is defined over$\mathbb{R}$, takes every semisimple element of$G(\mathbb{R})$to a$G(\mathbb{R})$-conjugate of its inverse, and is unique up to conjugacy by$G(\mathbb{R})$. We derive some consequences, including an analysis of groups for which every irreducible representation is self-dual, and a calculation of the Frobenius Schur indicator for such groups.
A Nutrient-Tunable Bistable Switch Controls Motility in Salmonella enterica Serovar Typhimurium
Authors: Koirala Santosh , Mears Patrick , Sim Martin , Golding Ido , Chemla Yann R. , Aldridge Phillip D. , Rao Christopher V. 
Published: August 2014

ABSTRACT

Many bacteria are motile only when nutrients are scarce. In contrast,
Salmonella enterica
serovar Typhimurium is motile only when nutrients are plentiful, suggesting that this bacterium uses motility for purposes other than foraging, most likely for host colonization. In this study, we investigated how nutrients affect motility in
S. enterica
and found that they tune the fraction of motile cells. In particular, we observed coexisting populations of motile and nonmotile cells, with the distribution being determined by the concentration of nutrients in the growth medium. Interestingly,
S. enterica
responds not to a single nutrient but apparently to a complex mixture of them. Using a combination of experimentation and mathematical modeling, we investigated the mechanism governing this behavior and found that it results from two antagonizing regulatory proteins, FliZ and YdiV. We also found that a positive feedback loop involving the alternate sigma factor FliA is required, although its role appears solely to amplify FliZ expression. We further demonstrate that the response is bistable: that is, genetically identical cells can exhibit different phenotypes under identical growth conditions. Together, these results uncover a new facet of the regulation of the flagellar genes in
S. enterica
and further demonstrate how bacteria employ phenotypic diversity as a general mechanism for adapting to change in their environment.

IMPORTANCE
Many bacteria employ flagella for motility. These bacteria are often not constitutively motile but become so only in response to specific environmental cues. The most common is nutrient starvation. Interestingly, in
Salmonella enterica
serovar Typhimurium, nutrients enhance the expression of flagella, suggesting that motility is used for purposes other than foraging. In this work, we investigated how nutrients affect motility in
S. enterica
and found that nutrients tune the fraction of motile cells within a population. Using both experimental and mathematical analysis, we determined the mechanism governing this tunable response. We further demonstrated that the response is bistable: that is, genetically identical cells can exhibit different phenotypes under identical growth conditions. These results reveal a new facet of motility in
S. enterica
and demonstrate that nutrients determine not only where these bacteria swim but also the fraction of them that do so.
Human Factor H (FH) Impairs Protective Meningococcal Anti-FHbp Antibody Responses and the Antibodies Enhance FH Binding
Authors: Costa Isabella , Pajon Rolando , Granoff Dan M. 
Published: August 2014

ABSTRACTThe meningococcal 4CMenB vaccine (Bexsero; Novartis) contains four antigens that can elicit serum bactericidal activity, one of which is factor H (FH)-binding protein (FHbp). FHbp specifically binds human complement FH. When humans are immunized, FHbp is expected to form a complex with FH, which could affect immunogenicity and safety. Wild-type mice (whose FH does not bind to FHbp) and human FH transgenic mice were immunized with three doses of 4CMenB, and their responses were compared. There were no significant differences between the serum bactericidal responses of transgenic and wild-type mice to strains with all of the antigens mismatched for 4CMenB except PorA or NadA. In contrast, against a strain mismatched for all of the antigens except FHbp, the transgenic mice had 15-fold weaker serum bactericidal antibody responses (P= 0.0006). Binding of FH downregulates complement. One explanation for the lower anti-FHbp serum bactericidal activity in the transgenic mice is that their postimmunization serum samples enhanced the binding of FH to FHbp, whereas the serum samples from the wild-type mice inhibited FH binding. Control antiserum from transgenic mice immunized with a low-FH-binding mutant FHbp (R41S) vaccine inhibited FH binding. Two 4CMenB-vaccinated transgenic mice developed serum IgM autoantibodies to human FH. Thus, human FH impairs protective serum anti-FHbp antibody responses, in part by skewing the antibody repertoire to FHbp epitopes outside the FH binding site. FHbp vaccines that bind FH may elicit FH autoantibodies. Mutant FHbp antigens with low FH binding could improve protection and, potentially, vaccine safety in humans.IMPORTANCETwo serogroup B meningococcal vaccines contain a novel antigen called factor H (FH)-binding protein (FHbp). FHbp specifically binds human FH, a plasma protein that downregulates complement. One vaccine (4CMenB; Novartis) is licensed in Europe, Canada, and Australia. When humans are immunized, FHbp can complex with FH. We compared the immunogenicity of 4CMenB vaccine in wild-type mice, whose own FH does not bind to FHbp, and human FH transgenic mice. Transgenic mice had respective antibody responses similar to those of wild-type mice to 4CMenB antigens that do not bind FH. However, the protective antibody responses of the transgenic mice to FHbp were impaired, largely because the antibodies did not inhibit but rather enhanced the binding of FH to FHbp. Two transgenic mice developed serum IgM autoantibodies to FH. Mutant FHbp antigens with low FH binding likely will elicit greater protection in humans than FHbp vaccines that bind FH and have a lower risk of FH autoantibodies.
Vitamin D supplementation in neonates
Authors: Wu Zhe 
Published: August 2014

AbstractVitamin D deficiency may lead to the development of rickets. In our paediatrics department in a major London hospital, we audited the number of babies with low vitamin D levels attending our prolonged jaundice clinic. Prior to our newly designed intervention, those babies with low vitamin D levels would be given a letter to encourage collection of supplementation from their GP. The GP would receive a letter which included a 14-page guideline on vitamin D supplementation.For this project, we included all breastfed babies that attended our prolonged jaundice clinic between August 2012 and December 2012. Those babies that were either vitamin D deficient or insufficient were identified. We then followed up these patients and asked them whether they were being prescribed the correct supplementation after being identified as vitamin deficient. For our intervention, we designed a leaflet to simplify guidelines that was then distributed to mothers and their GPs. Following this intervention, we re-audited the new cohort of patients who received the leaflet between August and November 2013.The study found 71% of babies to be vitamin D deficient. Moreover, almost two in five mothers had less than the recommended six months of vitamin supplementation during pregnancy. After identifying a deficiency, one would expect that uptake of vitamin supplementation would increase dramatically. However, only four in 10 babies went on to receive the correct dose and preparation of supplements. A marked increase in uptake was seen during the re-audit post intervention, with 71% of babies receiving correct supplementation.While an increase in government advertising would have contributed to the rise in uptake of vitamin D supplementation, a leaflet proved to be a simple yet effective intervention in improving vitamin uptake in babies. As a result, this was then implemented as part of trust guidelines.
Some minisuperspace model for the Faddeev formulation of gravity
Authors: Khatsymovsky V. M. 
Published: August 2014

We consider Faddeev formulation of General Relativity (GR) in which the metric is composed of ten vector fields or a 4 ×10 tetrad. This formulation reduces to the usual GR upon partial use of the field equations. A distinctive feature of the Faddeev action is its finiteness on the discontinuous fields. This allows to introduce its minisuperspace formulation where the vector fields are constant everywhere on ℝ4 with exception of a measure zero set (the piecewise constant fields). The fields are parametrized by their constant values independently chosen in, e.g. the 4-simplices or, say, parallelepipeds into which ℝ4 can be decomposed. The form of the action for the vector fields of this type is found. We also consider the piecewise constant vector fields approximating the fixed smooth ones. We check that if the regions in which the vector fields are constant are made arbitrarily small, the minisuperspace action and equations of motion tend to the continuum Faddeev ones.
Compiling CSPs: A Complexity Map of (Non-Deterministic) Multivalued Decision Diagrams
Authors: Amilhastre Jérôme , Fargier Hélène , Niveau Alexandre , Pralet Cédric 
Published: August 2014

Constraint Satisfaction Problems (CSPs) offer a powerful framework for representing a great variety of problems. The difficulty is that most of the requests associated with CSPs are NP-hard. When these requests have to be addressed online, Multivalued Decision Diagrams (MDDs) have been proposed as a way to compile CSPs. In the present paper, we draw a compilation map of MDDs, in the spirit of the NNF compilation map, analyzing MDDs according to their succinctness and to their tractable transformations and queries. Deterministic ordered MDDs are a generalization of ordered binary decision diagrams to non-Boolean domains: unsurprisingly, they have similar capabilities. More interestingly, our study puts forward the interest of non-deterministic ordered MDDs: when restricted to Boolean domains, they capture OBDDs and DNFs as proper subsets and have performances close to those of DNNFs. The comparison to classical, deterministic MDDs shows that relaxing the determinism requirement leads to an increase in succinctness and allows more transformations to be satisfied in polynomial time (typically, the disjunctive ones). Experiments on random problems confirm the gain in succinctness.
Comparative Trends in the Incidence of Hospitalized Myocardial Infarction and Coronary Heart Disease in Adults With and Without Diabetes Mellitus in Western Australia From 1998 to 2010
Authors: Nedkoff Lee , Knuiman Matthew , Hung Joseph , Briffa Tom G. 
Published: August 2014

Background—
The risk of myocardial infarction (MI) is elevated in people with diabetes mellitus (DM) compared with non-DM counterparts. The aim of this study was to compare population trends in the incidence of hospitalized MI and coronary heart disease (CHD) in adults with and without DM.

Methods and Results—
All incident hospitalized MI and CHD events were identified from whole-population hospital data in Western Australia for 1998 to 2010. Annual age-standardized MI and CHD incidence rates were calculated for people with and without DM aged 35 to 84 years and age-adjusted trends estimated from Poisson regression. There were 26 610 incident MI and 56 142 incident CHD cases during the study period. MI incidence rates fell in men (−2.9%/y; 95% confidence interval [CI], −3.7 to −2.1) and women (−3.8%/y; 95% CI, −4.8 to −2.1) with DM, representing overall reductions of 35% and 43% respectively, with comparable reductions in incident CHD. Downward trends in MI incidence in those with DM were most apparent in 55- to 84-year olds. In adults without DM, there was no decline in MI incidence but a small significant decrease in incident CHD (men, −1.5%/y; 95% CI, −1.8 to −1.2 and women, −1.3%/y; 95% CI, −1.8 to −0.9). Incidence rate ratios for MI in men with versus without DM declined from 4.5 (95% CI, 4.2–4.8) to 3.1 (95% CI, 2.9–3.3) and from 6.0 (95% CI, 5.4–6.6) to 3.8 (95% CI, 3.5–4.1) in women between 1998 and 2010.

Conclusions—
There have been significant reductions in incidence rates of MI and CHD in adults with DM between 1998 and 2010; however, the excess risk of MI incidence remains 3 to 4× greater in people with DM.
NR2B Phosphorylation at Tyrosine 1472 Contributes to Brain Injury in a Rodent Model of Neonatal Hypoxia-Ischemia
Authors: Knox Renatta , Brennan-Minnella Angela M. , Lu Fuxin , Yang Diana , Nakazawa Takanobu , Yamamoto Tadashi , Swanson Raymond A. , Ferriero Donna M. , Jiang Xiangning 
Published: August 2014

Background and Purpose—
The NR2B subunit of the N-methyl-d-aspartate (NMDA) receptor is phosphorylated by the Src family kinase Fyn in brain, with tyrosine (Y) 1472 as the major phosphorylation site. Although Y1472 phosphorylation is important for synaptic plasticity, it is unknown whether it is involved in NMDA receptor–mediated excitotoxicity in neonatal brain hypoxia-ischemia (HI). This study was designed to elucidate the specific role of Y1472 phosphorylation of NR2B in neonatal HI in vivo and in NMDA-mediated neuronal death in vitro.

Methods—
Neonatal mice with a knockin mutation of Y1472 to phenylalanine (YF-KI) and their wild-type littermates were subjected to HI using the Vannucci model. Brains were scored 5 days later for damage using cresyl violet and iron staining. Western blotting and immunoprecipitation were performed to determine NR2B tyrosine phosphorylation. Expression of NADPH oxidase subunits and superoxide production were measured in vivo. NMDA-induced calcium response, superoxide formation, and cell death were evaluated in primary cortical neurons.

Results—

After neonatal HI, YF-KI mice have reduced expression of NADPH oxidase subunit gp91
phox
and p47
phox
and superoxide production, lower activity of proteases implicated in necrotic and apoptotic cell death, and less brain damage when compared with the wild-type mice. In vitro, YF-KI mutation diminishes superoxide generation in response to NMDA without effect on calcium accumulation and inhibits NMDA and glutamate-induced cell death.

Conclusions—
Upregulation of NR2B phosphorylation at Y1472 after neonatal HI is involved in superoxide-mediated oxidative stress and contributes to brain injury.