bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Simulations of Counter Current Flow Experiments Using a Morphology Detection Algorithm
Authors: Höhne Thomas , Deendarlianto
Published: October 2012

In order to improve the understanding of counter-current two-phase flows and to validate new physical models, CFD simulations of 1/3rd scale model of the hot leg of a German Konvoi PWR with rectangular cross section was performed. Selected counter-current flow limitation (CCFL) experiments at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) were calculated with ANSYS CFX 12.1 using the multi-fluid Euler-Euler modeling approach. The transient calculations were carried out using a gas/liquid inhomogeneous multiphase flow model coupled with a SST turbulence model for each phase. In the simulation, the surface drag was approached by a new correlation inside the Algebraic Interfacial Area Density (AIAD) model. The AIAD model allows the detection of the morphological form of the two phase flow and the corresponding switching via a blending function of each correlation from one object pair to another. As a result this model can distinguish between bubbles, droplets and the free surface using the local liquid phase volume fraction value. A comparison with the high-speed video observations shows a good qualitative agreement. The results indicated that quantitative agreement of the CCFL characteristics between calculation and experimental data was obtained. To validate the model and to study scaling effects CFD simulations of the CCFL phenomenon in a full scale PWR hot leg of the UPTF test facility were performed. Also these results indicated a good agreement between the calculation and experimental data. The final goal is to provide an easy usable AIAD framework for all ANSYS CFX users, with the possibility of the implementation of their own correlations.
The Importance of Correct Modeling of Bubble Size and Condensation in Prediction of Sub-Cooled Boiling Flows
Authors: Lo S. , Splawski A. , Yun B.J.
Published: October 2012

This paper describes the updating of the sub-cooled boiling model used in CFD codes with the more recent and better sub-models. The improved sub-models include: Hibiki and Ishii [1] correlation for nucleation site density, Kocamustafaogullari [2] correlation for bubble departure diameter and the S-gamma model of Lo and Rao [3] for bubble size distribution in the flow. The new model has been tested against measured data from Debora [4] and Bartolomei [5]. The results show that improvement in the bubble size prediction has the most significant impact on the accuracy of the model.
Notre Dame Du Haut by Spherical Photogrammetry Integrated by Point Clouds Generated by Multi-View Software
Authors: Fangi Gabriele , Pierdicca Roberto
Published: October 2012

A convenient new photogrammetric technique, the Multi-Image Spherical Photogrammetry (MISP), particularly suitable for metric recording of architecture, has been set up and already used in many projects (Fangi, 2007, 2008, 2009, 2010, 2011). From a unique point of view, photographs are taken 360° around to form a spherical panorama. This panorama is suitable for measurements. The advantages in comparison with traditional pin-hole photogrammetry are many: the speed of the survey, the low-cost of the system, the drastic reduction of the photogrammetric models.

The disadvantages consist in the fact that the only suitable points for plotting are those easily identifiable in the different panoramas, because of lack of stereoscopy. In order to solve this problem the following steps have been made:

To use web service of Photosynth to get the orientation of a flurry of photos [27]; To generate dense point cloud by PMVS-2 (Furukawa,[28]); To edit the point cloud with Mesh Lab, an open source software [26]; To employ a suite of modeling programs to create a 3D model of the church.
Selective Sampling and Laser-Induced Breakdown Spectroscopy (LIBS) Analysis of Organic Explosive Residues on Polymer Surfaces
Authors: Fernandez-Bravo Angel , Lucena Patricia , Laserna José Javier
Published: October 2012

A method for selective sampling and analysis of explosive residues on solid surfaces based on laser-induced breakdown spectroscopy (LIBS) is presented. Organic explosives are difficult to analyze when present as residues on organic materials. Under these circumstances LIBS suffers from the limitations imposed by the limited spectroscopic information available for the analysis. Since ablation and subsequent plasma formation are sensitive to the beam focal conditions and the pulse energy deposited on the surface, the choice of an appropriate set of experimental conditions increases the surface sensitivity of the analysis and hence a selective inspection of the residue in the absence of spectral contribution from the organic support analyzed. 2-Mononitrotoluene (MNT), 2,6- dinitrotoluene (DNT), and 2,4,6-trinitrotoluene (TNT) are used as model residues, whereas nylon and Teflon are used as illustrative surfaces of daily life objects. The results demonstrate that selective sampling is successfully achieved in all cases when the plasma formation threshold of the residues and the object is substantially different. Plasma imaging demonstrates that the species distribution along the plume changes with beam focal conditions, which is exploited here to further increase the selectivity of the approach.
The Memory of Labor Oppression in Korean Cinema: The Death of a Young Worker in Single Spark (1995)
Authors: Park Seung Hyun
Published: October 2012

Single Spark (1995) is a retrospective work discussing the growth of the labor movement under the authoritarian rule of the Park government. This focuses on the life of a young worker named Tae-Il Chon,2 who immolated himself to protest against labor oppression at the age of 23 in 1970.
It deals with the labor movement in the 1970s, but it does not attach importance to the tension between the working class and employers/capitalists. Rather than depicting a violent conflict, the film highlights a sense of inevitability regarding the labor movement where both administration
officials and employers pay no regard to labor laws, laws that are generally considered to favor the management more than the working class.
Reflexivity in Recent Iranian Cinema: The Case of Mohsen Makhmalbaf
Authors: Totaro Donoto
Published: October 2012

My intention in this essay is to analyze the use of reflexivity in the films of director Mohsen Makhmalbaf, within the context of recent Iranian cinema. To begin, filmic reflexivity is marked by the following elements: -foregrounding the mode of production through a formal or stylistic
gesture (such as the use of an iris effect to refer to silent film) or through stylistic virtuosity; -foregrounding the mode of production by revealing the cinema apparatus (i.e., presence of the camera, light poles, clapper, etc.); -exposing the artist as the maker of meaning in any of the
two ways above or by referencing the artist's own life history; -alluding to previous films or filmmakers, to either announce a source of influence, to pay homage, or to add a layer of meaning to the film's text.
Resisting the Stage: Imaging/Imagining Ruan Lingyu in Stanley Kwan's Actress
Authors: Stokes Lisa Odham , Hoover Michael
Published: October 2012

Gender has figured prominently in the work of director Stanley Kwan, one of several male Hong Kong filmmakers (Tsui Hark and Ching Siu-tung are two others) whose consideration of women and sexuality in the 1980s and 1990s deconstructed the ways that cinema "naturalizes" masculine
fantasies and ideologies.
Pseudo-embeddings and pseudo-hyperplanes
Authors: De Bruyn B.
Published: October 2012

We generalize some known results regarding hyperplanes and projective embeddings of point-line geometries with three points per line to geometries with an arbitrary but finite number of points on each line. In order to generalize these results, we need to introduce the new notions of pseudo-hyperplane, (universal) pseudo-embedding, pseudo-embedding rank and pseudo-generating rank. We prove several connections between these notions and address the problem of the existence of (certain) pseudo-embeddings. We apply this to several classes of point-line geometries. We also determine the pseudo-embedding rank and the pseudo-generating rank of the projective space PG(n; 4) and the affine space AG(n; 4).
The Perspectives of Children and Young People Living with Cleft Lip and Palate: A Review of Qualitative Literature
Authors: Sharif Mohammad Owaise , Callery Peter , Tierney Stephanie
Published: October 2012

Objective

To explore the experiences of children and young people with cleft lip and/or palate (CL/P) in relation to being treated for and living with this condition.

Design

A systematic review of qualitative research. Electronic databases and hand-searching were employed to identify relevant studies. The review centered on studies examining the views or experiences of young patients first-hand. Any study using a qualitative/mixed method design was eligible for inclusion.

Results

From 184 potential references, 38 papers were read in full, from which only two studies of young people met all the review's inclusion criteria. Common reasons for exclusion were not being a qualitative study, not focusing on CL/P, or data coming from parents only. A further two papers provided a retrospective account of childhood with CL/P from interviews with adults. Their suitability for the review's aims was limited, but they were discussed.

Conclusions

This review demonstrates that there is a paucity of evidence about the experiences of young people living with CL/P. No studies of children and only two studies of young people met all inclusion criteria. Identified papers implied that more attention is needed within families and services to help young people manage everyday difficulties such as bullying and self-consciousness due to facial difference.
Protective Potential of Non‐Dialyzable Material Fraction of Cranberry Juice on the Virulence of P. gingivalis and F. nucleatum Mixed Infection
Authors: Polak David , Naddaf Raja , Shapira Lior , Weiss Ervin I. , Houri‐Haddad Yael
Published: October 2012

Background: Periodontitis is a polymicrobial infectious disease. A novel potential chemical treatment modality may lie in bacterial anti‐adhesive materials, such as cranberry juice fractions. The aim of this study is to explore the effect of high molecular weight cranberry constituent (non‐dialyzable material [NDM]) on the virulence of a mixed infection with Porphyromonas gingivalis and Fusobacterium nucleatum in mice.

Methods: In vitro, the anti‐adhesive property of NDM was validated on epithelial cell culture, and inhibition of coaggregation was tested using a coaggregation assay. The in vivo effect was tested on the outcome of experimental periodontitis induced by a P. gingivalis and F. nucleatum mixed infection, and also on the local host response using the subcutaneous chamber model of infection. Phagocytosis was also tested on RAW macrophages by the use of fluorescent‐labeled bacteria.

Results: NDM was found to inhibit the adhesion of both species of bacteria onto epithelial cells and to inhibit coaggregation in a dose‐dependent manner. NDM consumption by mice attenuated the severity of experimental periodontitis compared with a mixed infection without NDM treatment. In infected subcutaneous chambers, NDM alone reduced tumor necrosis factor‐α (TNF‐α) levels induced by the mixed infection. In vitro, NDM eliminated TNF‐α expression by macrophages that were exposed to P. gingivalis and F. nucleatum, without impairing their viability. Furthermore, NDM increased the phagocytosis of P. gingivalis.

Conclusions: The results indicate that the use of NDM may hold potential protective and/or preventive modalities in periodontal disease. Underlying mechanisms for this trait may perhaps be the anti‐adhesive properties of NDM or its potential effect on inflammation.
Prospective Associations of B-Type Natriuretic Peptide With Markers of Left Ventricular Function in Individuals With and Without Type 2 Diabetes
Authors: Kroon Maria H. , van den Hurk Katja , Alssema Marjan , Kamp Otto , Stehouwer Coen D.A. , Henry Ronald M.A. , Diamant Michaela , Boomsma Frans , Nijpels Giel , Paulus Walter J. , Dekker Jacqueline M.
Published: October 2012

OBJECTIVE

Heart failure is common in individuals with type 2 diabetes, and early detection of individuals at risk may offer opportunities for prevention. We aimed to explore 1) prospective associations of B-type natriuretic peptide (BNP) levels in a non–heart failure range with changes in markers of left ventricular (LV) function and 2) possible effect modification by type 2 diabetes in a population-based cohort.

RESEARCH DESIGN AND METHODS

Echocardiographic measurements were performed at baseline (2000–2001) and follow-up (2007–2009), together with standardized physical examinations and BNP measurements on 300 individuals (mean age 66 years, 32% with type 2 diabetes) of the longitudinal Hoorn Study. Multivariate linear regression analyses were performed to investigate associations of baseline BNP (<100 pg/mL) in individuals without prevalent heart failure at baseline with changes in LV mass index, LV ejection fraction, left atrial volume index, and ratio of early diastolic LV inflow velocity (E) to early diastolic lengthening velocity (e′) (E/e′).

RESULTS

In all individuals, higher BNP was associated with 8-year increases in left atrial volume index. Higher BNP was also associated with increasing LV mass index and E/e′. These associations were significantly stronger in individuals with type 2 diabetes compared with the nonsignificant associations in individuals without type 2 diabetes.

CONCLUSIONS

This 8-year follow-up study shows that higher BNP levels in a non–heart failure range were associated with an increased LV mass and deteriorated LV diastolic function, particularly in individuals with type 2 diabetes. This implies that the presence or absence of type 2 diabetes should be taken into account if BNP levels are used to assess future heart failure risk.
Metabolic and Inflammatory Links to Depression in Youth With Diabetes
Authors: Hood Korey K. , Lawrence Jean M. , Anderson Andrea , Bell Ronny , Dabelea Dana , Daniels Stephen , Rodriguez Beatriz , Dolan Lawrence M. ,   for the SEARCH for Diabetes in Youth Study Group
Published: October 2012

OBJECTIVE

Youth with diabetes are at increased risk for depression. The objectives of this study were to provide preliminary evidence that this at-risk status for depression is associated with metabolic and inflammatory markers and to inform future, more stringent examinations of the directionality of these associations.

RESEARCH DESIGN AND METHODS

Data from SEARCH for Diabetes in Youth (SEARCH), an observational study of U.S. children diagnosed with diabetes at <20 years of age, were used for these analyses. SEARCH participants were drawn from four geographically defined populations in Ohio, Washington, South Carolina, and Colorado; health plan enrollees in Hawaii and California; and Indian Health Service beneficiaries from four Native American populations. Participants were 2,359 youth with diabetes from the 2001 prevalent and 2002–2004 incident SEARCH cohorts. Depression was measured with the Center for Epidemiologic Studies Depression scale. Eight metabolic and inflammatory markers were measured: adiponectin, leptin, C-reactive protein, serum amyloid A, apolipoprotein B (apoB), lipoprotein A, interleukin-6, and LDL.

RESULTS

Six of eight markers were significantly (P < 0.006) associated with depression in youth with diabetes in bivariate analyses. In general, higher levels of depression were associated with indicators of worse metabolic or inflammatory functioning. In regression models stratified by diabetes type and accounting for demographic and clinical characteristics, only higher levels of apoB remained associated with higher levels of depression in youth with type 1 diabetes.

CONCLUSIONS

These data suggest that depression reported by youth with diabetes is partially associated with metabolic abnormalities and systemic inflammation.
Effect of Combination Therapy With Fenofibrate and Simvastatin on Postprandial Lipemia in the ACCORD Lipid Trial
Authors: Reyes-Soffer Gissette , Ngai Colleen I. , Lovato Laura , Karmally Wahida , Ramakrishnan Rajasekhar , Holleran Stephen , Ginsberg Henry N.
Published: October 2012

OBJECTIVE

The Action to Control Cardiovascular Risk in Diabetes lipid study (ACCORD Lipid), which compared the effects of simvastatin plus fenofibrate (FENO-S) versus simvastatin plus placebo (PL-S) on cardiovascular disease outcomes, measured only fasting triglyceride (TG) levels. We examined the effects of FENO-S on postprandial (PP) lipid and lipoprotein levels in a subgroup of ACCORD Lipid subjects.

RESEARCH DESIGN AND METHODS

We studied 139 subjects (mean age of 61 years, 40% female, and 76% Hispanic or black) in ACCORD Lipid, from a total 529 ACCORD Lipid subjects in the Northeast Clinical Network. PP plasma TG, apolipoprotein (apo)B48, and apoCIII were measured over 10 h after an oral fat load.

RESULTS

The PP TG incremental area under the curve (IAUC) above fasting (median and interquartile range [mg/dL/h]) was 572 (352–907) in the FENO-S group versus 770 (429–1,420) in the PL-S group (P = 0.008). The PP apoB48 IAUC (mean ± SD [μg/mL/h]) was also reduced in the FENO-S versus the PL-S group (23.2 ± 16.3 vs. 35.2 ± 28.6; P = 0.008). Fasting TG levels on the day of study were correlated with PP TG IAUC (r = 0.73 for FENO-S and r = 0.62 for PL-S; each P < 0.001). However, the fibrate effect on PP TG IAUC was a constant percentage across the entire range of fasting TG levels, whereas PP apoB48 IAUC was only reduced when fasting TG levels were increased.

CONCLUSIONS

FENO-S lowered PP TG similarly in all participants compared with PL-S. However, levels of atherogenic apoB48 particles were reduced only in individuals with increased fasting levels of TG. These results may have implications for interpretation of the overall ACCORD Lipid trial, which suggested benefit from FENO-S only in dyslipidemic individuals.
Serum Levels of the Adipokine Progranulin Depend on Renal Function
Authors: Richter Judit , Focke Denise , Ebert Thomas , Kovacs Peter , Bachmann Anette , Lössner Ulrike , Kralisch Susan , Kratzsch Jürgen , Beige Joachim , Anders Matthias , Bast Ingolf , Blüher Matthias , Stumvoll Michael , Fasshauer Mathias
Published: October 2012

OBJECTIVE

Progranulin has recently been introduced as a novel adipokine inducing insulin resistance and obesity. In the current study, we investigated renal elimination, as well as association of the adipokine with markers of the metabolic syndrome.

RESEARCH DESIGN AND METHODS

Progranulin serum levels were quantified by enzyme-linked immunosorbent assay and correlated to anthropometric and biochemical parameters of renal function and glucose and lipid metabolism, as well as inflammation, in 532 patients with stages 1–5 of chronic kidney disease (CKD).

RESULTS

Median serum progranulin levels adjusted for age, sex, and BMI were significantly different between CKD stages with highest values detectable in stage 5 (stage 1, 58.3 µg/L; stage 2, 63.0 µg/L; stage 3, 65.4 µg/L; stage 4, 68.8 µg/L; and stage 5, 90.6 µg/L). Furthermore, CKD stage was the strongest independent predictor of circulating progranulin in our cohort. In addition, high-sensitivity interleukin-6 and adiponectin remained significantly and independently correlated with the adipokine.

CONCLUSIONS

We demonstrate that progranulin serum levels increase with deteriorating renal function. These findings are in accordance with the hypothesis that renal clearance is a major elimination route for circulating progranulin. Furthermore, the adipokine is positively and independently associated with markers of inflammation and adiponectin.
Long-Term Efficacy and Safety of Linagliptin in Patients With Type 2 Diabetes and Severe Renal Impairment
Authors: McGill Janet B. , Sloan Lance , Newman Jennifer , Patel Sanjay , Sauce Christophe , von Eynatten Maximilian , Woerle Hans-Juergen
Published: October 2012

OBJECTIVE

This placebo-controlled study assessed long-term efficacy and safety of the dipeptidyl peptidase-4 inhibitor linagliptin in patients with type 2 diabetes and severe renal impairment (RI).

RESEARCH DESIGN AND METHODS

In this 1-year, double-blind study, 133 patients with type 2 diabetes (HbA1c 7.0–10.0%) and severe RI (estimated glomerular filtration rate [eGFR] <30 mL/min/1.73 m2) at screening were randomized to linagliptin 5 mg (n = 68) or placebo (n = 65) once daily, added to existing background therapy. The primary efficacy end point was HbA1c change from baseline to week 12. Efficacy and safety end points were assessed after 1 year.

RESULTS

At week 12, adjusted mean HbA1c decreased by −0.76% with linagliptin and −0.15% with placebo (treatment difference, −0.60%; 95% CI −0.89 to −0.31; P < 0.0001). HbA1c improvements were sustained with linagliptin (−0.71%) over placebo (0.01%) at 1 year (treatment difference −0.72%, −1.03 to −0.41; P < 0.0001). Mean insulin doses decreased by −6.2 units with linagliptin and −0.3 units with placebo. Overall adverse event incidence was similar over 1 year (94.1 vs. 92.3%). Incidence of severe hypoglycemia with linagliptin and placebo was comparably low (three patients per group). Linagliptin and placebo had little effect on renal function (median change in eGFR, −0.8 vs. −2.2 mL/min/1.73 m2), and no drug-related renal failure occurred.

CONCLUSIONS

In patients with type 2 diabetes and severe RI, linagliptin provided clinically meaningful improvements in glycemic control with very low risk of severe hypoglycemia, stable body weight, and no cases of drug-related renal failure. The potential for linagliptin to spare insulin and provide long-term renal safety warrants further investigations.
Introduction of a Research component in the undergraduate medical curriculum – Review of a trend
Authors: Sreedharan Jayadevan
Published: October 2012

The question of whether a research component should be an integral part of medical curriculum has been debated in the past and is still controversial. Patient care is the most important aspect of a medical graduate but teaching, administration and research are also essential aspects. The implementation of a research component is more important at a student level as it helps to develop a judicious insight in their academic and clinical practice, which every medical person should possess.DOI: http://dx.doi.org/10.3126/nje.v2i3.6901Nepal Journal of Epidemiology 2012;2(3):200-4
Study of Risk factors of Coronary Heart Disease in Urban Slums of Patna
Authors: Singh Rashmi , Mukherjee Madhumita , Kumar Rajeev , Singh Ritu , Pal Ranabir
Published: October 2012

Background Coronary Heart Diseases (CHDs) are imminent cause of disability and death with economic adverse effects in the disadvantaged population in India. Materials and Methods This population based study was conducted from 1st December 2010 till 31st May 2011 among the adults in the slums of Patna to assess the magnitude and risk factors of CHDs concerning age, sex, tobacco use, alcohol consumption, physical activity, weight, height, waist circumference, blood pressure and random capillary blood glucose (RCBG). Results Among 3118 participants 16.36 percent (males 18.79 %, females 14.48 %) were hypertensive; 26.3 percent (males 25.94 %, females 26.58 %) had elevated RCBG; 4.46 percent were Diabetic. High body mass index (BMI), waist circumference (WC) and waist to height ratio (WHtR) was noted in 31.94 percent (males 31.83%, females 32.03%), 50.45 percent (males 39.1%, females 59.17%), 86.53 percent (male 83.12%, female 89.15%) respectively; tobacco users were 12.54 percent, while 9.14 percent reported alcohol consumption; 33.64 percent were sedentary (males 30.55%, females 37.65%). BMI, WC, WHtR, tobacco use, alcohol consumption and physical inactivity were significantly associated with hypertension (p < 0.05). Elevated RCBG was significantly associated with increased BMI, WC, WHtR. Multivariate logistic regression revealed that BMI, WHtR and alcohol were associated with hypertension, not with elevated RCBG. ConclusionOur study indicated that CHDs and their risk factors are not only limited to affluent societies but also affect the underprivileged mass. Preventive care and multipronged intervention including extensive behavior change communication needs to be organized to reduce the risk of CHDs in urban poor.DOI: http://dx.doi.org/10.3126/nje.v2i3.6902Nepal Journal of Epidemiology 2012;2(3): 205-12
Investigations on laser welding of magnesium alloys
Authors: Dai Jun , Huang Jian , Li Zhuguo , Dong Jie , Wu Yixiong
Published: October 2012

The welding processes of three different magnesium alloys ZK60, AZ31, and Mg-rare earth alloy NZ30K were studied using a high-power CO2 laser. The microstructure and tensile strength of welded joints were tested and analyzed. With increasing welding speed the tensile strength and total elongation of welded joints of ZK60 alloy are improved. The ultimate tensile strength of the welded joint of ZK60 is 211.18 MPa, 90% of the base metal. The tensile strengths of welded joints of AZ31 and NZ30K are better than those of the base metal. The expansion of the plasma of laser-welded ZK60 is the strongest with the highest temperature.
Study on the dielectric properties of CaCu3Ti4O12 ceramics using the one-dimensional Ising model
Authors: You Jinghan , Ju Weiwei , Tang Zhengxin , Li Liben
Published: October 2012

As a high-dielectric cubic perovskite-related material, CaCu3Ti4O12 (CCTO) has a dielectric constant of 104 at room temperature. Up to now the origin of the peculiar dielectric phenomena in CCTO is not fully understood and there are some disputes in the literature. In this paper, based a one-dimensional Ising model under static electric field, the dielectric properties of CCTO were studied. Results indicate that the theory is nearly consistent with the experiment.
Performance analysis of the protective effects of bicycle helmets during impact and crush tests in pediatric skull models
Authors: Mattei Tobias A. , Bond Brandon J. , Goulart Carlos R. , Sloffer Chris A. , Morris Martin J. , Lin Julian J.
Published: October 2012

Object

Bicycle accidents are a very important cause of clinically important traumatic brain injury (TBI) in children. One factor that has been shown to mitigate the severity of lesions associated with TBI in such scenarios is the proper use of a helmet. The object of this study was to test and evaluate the protection afforded by a children's bicycle helmet to human cadaver skulls with a child's anthropometry in both “impact” and “crushing” situations.

Methods

The authors tested human skulls with and without bicycle helmets in drop tests in a monorail-guided free-fall impact apparatus from heights of 6 to 48 in onto a flat steel anvil. Unhelmeted skulls were dropped at 6 in, with progressive height increases until failure (fracture). The maximum resultant acceleration rates experienced by helmeted and unhelmeted skulls on impact were recorded by an accelerometer attached to the skulls. In addition, compressive forces were applied to both helmeted and unhelmeted skulls in progressive amounts. The tolerance in each circumstance was recorded and compared between the two groups.

Results

Helmets conferred up to an 87% reduction in so-called mean maximum resultant acceleration over unhelmeted skulls. In compression testing, helmeted skulls were unable to be crushed in the compression fixture up to 470 pound-force (approximately 230 kgf), whereas both skull and helmet alone failed in testing.

Conclusions

Children's bicycle helmets provide measurable protection in terms of attenuating the acceleration experienced by a skull on the introduction of an impact force. Moreover, such helmets have the durability to mitigate the effects of a more rare but catastrophic direct compressive force. Therefore, the use of bicycle helmets is an important preventive tool to reduce the incidence of severe associated TBI in children as well as to minimize the morbidity of its neurological consequences.
Computation of Rate Constants for Some Chlorination Reactions of Mercury Atoms during Combustion
Authors: Qing Wang , Bowen Yang , Jingru Bai
Published: October 2012

The geometric optimizations of reactants, products and transition states have been made using the quantum chemistry MP2 method at the SDD/6-311 + + G(3df, 3pd) basis function levels. The properties of stable minima were validated by analysis of vibration frequencies. Furthermore, the microscopic reaction mechanisms have been investigated by ab initio calculations. Among those chlorination reactions involving mercury, the processes of the reaction Hg + HCl → HgCl + H are Hg + HCl → TS(HgClH) → HgCl + H, which include only one transition state (TS) and no intermediate (M), which is similar in character to the reactions HgCl + HCl → HgCl2 + H and HgCl + Cl → HgCl2. On the basis of the geometric optimization, the rate constants at every 1 degree interval from 200 K to 2000 K were calculated neither from experimental data nor by estimation, but directly from the quantum chemistry software ‘Khimera’.
Catalytic Mechanism and Activity of a Nitrogen Heterocycle Lanthanum(III) Complex in the Hydrolysis of bis(4-nitrophenyl) Phosphate Ester
Authors: Cai Shulan , Feng Famei , Zou Like , Huang Chun , Xie Jiaqing
Published: October 2012

The system made up of a nitrogen heterocycle ligand and lanthanum(III) ion was used in the catalytic hydrolysis of bis(4-nitrophenyl) phosphate ester (BNPP). This catalytic system showed higher catalytic activity in this hydrolysis and better reproducibility and stability than other similar lanthanum(III) ion systems. The rate of the catalytic hydrolysis was about 108-fold faster than that of its spontaneous hydrolysis under the same conditions. Compared with previous Cu(II) or Ni(II) complexes containing the same ligand in water, the activity of the macrocyclic La(III) complexe is increased ca 104-fold. The experimental evidence showed that the mon-hydroxy complex made of the nitrogen heterocycle ligand and lanthanum(III) ion is the active species as catalyst in the catalytic hydrolysis of BNPP.
Kinetic and Thermodynamic Studies of Adsorption of Heavy Metal Ions from Fuel Ethanol
Authors: Wang Zengdi , Yin Ping , Qu Rongjun , Yin Gui
Published: October 2012

The cleaning treatment of fuel ethanol plays an important role in its effective utilisation, and adsorption is one useful process to remove heavy metal ions from fuel ethanol solutions. In this work, a novel silica gel adsorbent functionalised with an aminophosphonic acid (denoted as SG-T-P) was developed, characterised, and used to remove heavy metal ions from fuel ethanol solutions. The adsorption properties of SG-T-P for Hg(II), Cu(II), Mn(II), Co(II), Zn(II), Ni(II), Fe(III) and Cd(II) in ethanol solutions were studied, revealing that SG-T-P had an excellent adsorption capacity for Hg(II). Furthermore, the kinetic data indicated that the adsorption process was governed by film diffusion and followed a pseudo-second-order rate model for SG-T-P. The thermodynamic parameters Δ G, Δ H and Δ S were – 6.80kJ mol−1 (35°C), 55.49 kJ mol−1, and 203.92 J K −1 mol −1, respectively. Thus, SG-T-P is effective and useful for the removal of Hg(II) from fuel ethanol solutions, and its good adsorption ability make it a promising candidate material for mercury uptake.
Theoretical, Kinetic and Mechanistic Studies of the Reaction between Dialkyl Acetylenedicarboxylates, Triphenylphosphine and Pyrrole in Organic Solvents
Authors: Shahraki Mehdi , Khorassani Sayyed Mostafa Habibi , Ebrahimi Ali , Maghsoodlou Malek Taher , Paknahad Ali
Published: October 2012

The kinetics of the reaction between triphenylphosphine, dialkyl acetylenedicarboxylates and pyrrole in dry organic solvents at different temperatures have been studied spectrophotometrically. The observed overall second rate constant ( k2)for reaction decreases with decreasing solvent dielectric constant and media temperature; k2 follows the Arrhenius equation, and the overall reaction is first order in both the dialkyl acetylenedicarboxylate and triphenylphosphine concentrations. The proposed mechanism has been evaluated, and the activation parameters Δ G≠, Δ S≠ and Δ H≠ for the first, rate-determining step, as an elementary reaction have been determined on the basis of Eyring equation. In addition, the Z- and E-isomers have been optimized at HF and B3LYP levels with the 6-311++G** basis set; the more stable is the E-isomer, in agreement with experimental data. Furthermore, to better understand the intramolecular interactions, atoms in molecules (AIM) calculations and natural population analysis (NPA) methods have been carried out. The 1H, 13C, and 31P NMR data of these ylides are consistent with results obtained from theoretical calculations.
Adsorption Kinetics of Au(III) Ions on a Novel Chelating Resin Silica-Gel Functionalized by an Amino Organophosphonic Acid
Authors: Yin Ping , Tian Yuan , Qu Rongjun , Zhang Jiang
Published: October 2012

The adsorption kinetics of Au(III) on a novel chelating resin namely silica gel functionalized by an amino phosphonic acid (denoted as SiO2–EDA–APA) were studied. The results showed that SiO2–EDA–APA could reach its saturation adsorption capacity within 4 h, and its excellent adsorption capacity for Au(III) was 234.61 mg g −1 when the initial solution concentration was 2.0 mmol L −1 at 35°C. The adsorption kinetics of the as-synthesized hybrid adsorbent for Au(III) at different temperatures can be modelled closely by a pseudo second-order rate equation. The thermodynamic parameters of adsorption, Δ G, Δ H and Δ S were – 18.89 kJ mol −1, 19.82 kJ mol −1, and 125.74 J K−1 mol −1, respectively. It can be concluded that the adsorption of Au(III) on SiO2–EDA–APA is a spontaneous, endotherminc process controlled by film diffusion, which results in its higher adsorption capacity at higher temperatures.
An Unusual Bismuth Ethanedisulfonate Network
Authors: Gschwind Fabienne , Jansen Martin
Published: October 2012

The three dimensional bismuth ethanedisulfonate framework Bi(O3SC2H4SO3)1.5(H2O)2 was synthesized under hydrothermal conditions using the bidentate ligand 1,2-ethanedisulfonate and then characterized through X-ray diffraction and elemental analyses. The bismuth cation coordinates at three different ethanedisulfonate ligands and has a coordination number of eight, which is accompanied by a distorted square antiprismatic configuration. Here, we report on the crystal structure of this bismuth metal–organic framework and its coordination behavior, which has thus far not been reported in heavier main group elements.
Oral Care during Pregnancy: Attitudes of Brazilian Public Health Professionals
Authors: Alves Renata Toledo , Ribeiro Rosangela Almeida , Costa Luciane Rezende , Leles Claudio Rodrigues , Freire Maria do Carmo Matias , Paiva Saul Martins
Published: October 2012

There is little information about health professionals’ behavior regarding oral health care during pregnancy. We evaluated attitudes of obstetricians/gynecologists, nurses, and dentists working at a public community service towards pregnant women’s oral health. Health professionals responded to a self-applied questionnaire. Cluster analysis identified two clusters of respondents; Chi-square, Student’s t test, and logistic regression were used to compare the two clusters in terms of the independent variables. Respondents were categorized into cluster 1 ‘less favorable’ (n = 159) and cluster 2 ‘more favorable’ (n = 124) attitudes. Professionals that had attended a residency or specialization program (OR = 2.08, 95% CI = 1.15–3.77, p = 0.016) and worked exclusively at the public service (OR = 2.15, 95% CI = 1.10–4.20, p = 0.025) presented more favorable attitudes. Obstetricians/gynecologists (OR = 0.22, 95% CI = 0.09–0.54, p = 0.001) and nurses (OR = 0.50, 95% CI = 0.29–0.86, p = 0.013) showed less favorable attitudes than dentists. Health care providers’ attitudes regarding pregnant women’s oral health were related to their occupation, qualification, and dedication to the public service.
Photoluminescence Intermittency from Single Quantum Dots to Organic Molecules: Emerging Themes
Authors: Riley Erin A. , Hess Chelsea M. , Reid Philip J.
Published: October 2012

Recent experimental and theoretical studies of photoluminescence intermittency (PI) or “blinking” exhibited by single core/shell quantum dots and single organic luminophores are reviewed. For quantum dots, a discussion of early models describing the origin of PI in these materials and recent challenges to these models are presented. For organic luminophores the role of electron transfer, proton transfer and other photophysical processes in PI are discussed. Finally, new experimental and data analysis methods are outlined that promise to be instrumental in future discoveries regarding the origin(s) of PI exhibited by single emitters.
MicroRNAs as Diagnostic Biomarkers in Gastric Cancer
Authors: Yin Ying , Li Jun , Chen Shujie , Zhou Tianhua , Si Jianmin
Published: October 2012

Considering the high mortality rates and the unfavorable prognosis of gastric cancer (GC) as well as the lack of a clinical predictive marker, which is sufficiently sensitive to GC, it is of great significance to investigate new sensitive and specific markers for GC diagnosis. MicroRNAs (miRNAs) could be a practical form of potential biomarkers in the diagnosis of human disease, and they are confirmed to be closely associated with GC. In this review, we discuss the recent research results that indicate the feasibility and clinical applications of miRNAs in GC. Although several challenges remain to be addressed, miRNAs have the potential to be applied in the diagnosis of GC.
A Multi-Channel Low-Power System-on-Chip for in Vivo Recording and Wireless Transmission of Neural Spikes
Authors: Bonfanti Andrea , Ceravolo Maria , Zambra Guido , Gusmeroli Riccardo , Baranauskas Gytis , Angotzi Gian Nicola , Vato Alessandro , Maggiolini Emma , Semprini Marianna , Spinelli Alessandro Sottocornola , Lacaita Andrea Leonardo
Published: October 2012

This paper reports a multi-channel neural spike recording system-on-chip with digital data compression and wireless telemetry. The circuit consists of 16 amplifiers, an analog time-division multiplexer, a single 8 bit analog-to-digital converter, a digital signal compression unit and a wireless transmitter. Although only 16 amplifiers are integrated in our current die version, the whole system is designed to work with 64, demonstrating the feasibility of a digital processing and narrowband wireless transmission of 64 neural recording channels. Compression of the raw data is achieved by detecting the action potentials (APs) and storing 20 samples for each spike waveform. This compression method retains sufficiently high data quality to allow for single neuron identification (spike sorting). The 400 MHz transmitter employs a Manchester-Coded Frequency Shift Keying (MC-FSK) modulator with low modulation index. In this way, a 1:25 Mbit/s data rate is delivered within a limited band of about 3 MHz. The chip is realized in a 0:35 µm AMS CMOS process featuring a 3 V power supply with an area of 3:1 x 2:7 mm2. The achieved transmission range is over 10 m with an overall power consumption for 64 channels of 17:2 mW. This figure translates into a power budget of 269 µW per channel, in line with published results but allowing a larger transmission distance and more efficient bandwidth occupation of the wireless link. The integrated circuit was mounted on a small and light board to be used during neuroscience experiments with freely-behaving rats. Powered by 2 AAA batteries, the system can continuously work for more than 100 hours allowing for long-lasting neural spike recordings.
2-[2-(Aziridin-1-yl)ethyl]-5,5-dimethyl-2,5-dihydro-4H-benzo [e]isoindol-4-one (Cytotoxic Oxonaphthalene-Pyrroles, Part IV)
Authors: Spreitzer Helmut , Puschmann Christiane
Published: October 2012

An aziridine-containing side chain is attached to an oxonaphthalene-annelated pyrrole in expectation of DNA alkylating properties. The cytotoxicity is evaluated against two cell lines, KB-31 and KB-8511, respectively.
Sarcophine-Diol Inhibits Expression of COX-2, Inhibits Activity of cPLA2, Enhances Degradation of PLA2 and PLCγ1 and Inhibits Cell Membrane Permeability in Mouse Melanoma B16F10 Cells
Authors: Szymanski Pawel T. , Muley Pratik , Ahmed Safwat A. , Khalifa Sherief , Fahmy Hesham
Published: October 2012

Sarcophine-diol (SD) is a semi-synthetic derivative of sarcophine with a significant chemopreventive effect against non-melanoma skin cancer both in vitro and in vivo. Recently, we have studied the effect of SD on melanoma development using the mouse melanoma B16F10 cell line. In this study, our findings show that SD suppresses cell multiplication and diminishes membrane permeability for ethidium bromide (EB), a model marker used to measure cell permeability for Ca2+ ions. SD also decreases protein levels of COX-2, and increases degradation of phospholipases PLA2 and PLCγ1 and diminishes enzymatic activity of the Ca2+-dependent cPLA2. This lower membrane permeability for Ca2+-ions, associated with SD, is most likely due to the diminished content of lysophosphosphatidylcholine (lysoPC) within cell membranes caused by the effect of SD on PLA2. The decrease in diacylglycerol (DAG) and inositol 1,4,5-triphosphate (IP3) due to inhibition of PLCγ1, leads to the downregulation of Ca2+-dependent processes within the cell and also inhibits the formation of tumors. These findings support our previous data suggesting that SD may have significant potential in the treatment of melanoma.
Micromanufacturing in Fused Silica via Femtosecond Laser Irradiation Followed by Gas-Phase Chemical Etching
Authors: Venturini Francesco , Sansotera Maurizio , Vazquez Rebeca Martinez , Osellame Roberto , Cerullo Giulio , Navarrini Walter
Published: October 2012

Femtosecond laser irradiation followed by chemical etching (FLICE) with hydrogen fluoride (HF) is an emerging technique for the fabrication of directly buried, three-dimensional microfluidic channels in silica. The procedure, as described in literature, consists of irradiating a silica slab followed by chemical etching using hydrogen fluoride. With aqueous HF the etching process is diffusion-limited and is self-terminating, leading to maximum microchannel lengths of about 1.5 mm, while the use of low-pressure gaseous HF etchant can quickly produce 3 mm long channels with an aspect ratio (Length/Diameter) higher than 25. By utilizing this methodology the aspect ratio is not constant, but depends on the length of the channel. When the microchannel is short the aspect ratio increases quickly until it reaches a maximum length at around 1400 µm. Thereafter the aspect ratio starts to decrease slowly. In this paper we present a variation of the low-pressure gaseous HF etching method, which is based on the dynamic displacement of the etchant. This method results in a 13% increase in the aspect ratio (L/D = 29) at the expense of a low etching speed (4 µm/min).
An Expeditious Iodine-Catalyzed Synthesis of 3-Pyrrole-substituted 2-Azetidinones
Authors: Bandyopadhyay Debasish , Cruz Jessica , Yadav Ram N. , Banik Bimal K.
Published: October 2012

2-Azetidinones and pyrroles are two highly important classes of molecules in organic and medicinal chemistry. A green and practical method for the synthesis of 3-pyrrole-substituted 2-azetidinones using catalytic amounts of molecular iodine under microwave irradiation has been developed. Following this method, a series of 3-pyrrole- substituted 2-azetidinones have been synthesized with a variety of substituents at N-1 and at C-4. The procedure is equally effective for mono- as well as polyaromatic groups at the N-1 position of the 2-azetidinone ring. The C-4 substituent has no influence either on the yield or the rate of the reaction. Optically pure 3-pyrrole-substituted 2-azetidinones have also been synthesized following this methodology. No deprotection/rearrangement has been identified in this process, even with highly acid sensitive group-containing substrates. A plausible mechanistic pathway has also been suggested based on the evidence obtained from 1H-NMR spectroscopy. The extreme rapidity with excellent reaction yields is believed to be the result of a synergistic effect of the Lewis acid catalyst (molecular iodine) and microwave irradiation.
Statistical Estimation of the Protein-Ligand Binding Free Energy Based On Direct Protein-Ligand Interaction Obtained by Molecular Dynamics Simulation
Authors: Fukunishi Yoshifumi , Nakamura Haruki
Published: October 2012

We have developed a method for estimating protein-ligand binding free energy (DG) based on the direct protein-ligand interaction obtained by a molecular dynamics simulation. Using this method, we estimated the DG value statistically by the average values of the van der Waals and electrostatic interactions between each amino acid of the target protein and the ligand molecule. In addition, we introduced fluctuations in the accessible surface area (ASA) and dihedral angles of the protein-ligand complex system as the entropy terms of the DG estimation. The present method included the fluctuation term of structural change of the protein and the effective dielectric constant. We applied this method to 34 protein-ligand complex structures. As a result, the correlation coefficient between the experimental and calculated DG values was 0.81, and the average error of DG was 1.2 kcal/mol with the use of the fixed parameters. These results were obtained from a 2 nsec molecular dynamics simulation.
Effects of Surface and Morphological Properties of Zeolite on Impedance Spectroscopy-Based Sensing Performance
Authors: Zhang Jianwei , Li Xiaogan , White Jeremy , Dutta Prabir K.
Published: October 2012

Measurement by impedance spectroscopy of the changes in intrazeolitic cation motion of pressed pellets of zeolite particles upon adsorption of dimethylmethylphosphonate (DMMP) provides a strategy for sensing DMMP, a commonly used simulant for highly toxic organophosphate nerve agents. In this work, two strategies for improving the impedance spectroscopy based sensing of DMMP on zeolites were investigated. The first one is the use of cerium oxide (CeO2) coated on the zeolite surface to neutralize acidic groups that may cause the decomposition of DMMP, and results in better sensor recovery. The second strategy was to explore the use of zeolite Y membrane. Compared to pressed pellets, the membranes have connected supercages of much longer length scales. The zeolite membranes resulted in higher sensitivity to DMMP, but recovery of the device was significantly slower as compared to pressed zeolite pellets.
WikiSensing: An Online Collaborative Approach for Sensor Data Management
Authors: Silva Dilshan , Ghanem Moustafa , Guo Yike
Published: October 2012

This paper presents a new methodology for collaborative sensor data management known as WikiSensing. It is a novel approach that incorporates online collaboration with sensor data management. We introduce the work on this research by describing the motivation and challenges of designing and developing an online collaborative sensor data management system. This is followed by a brief survey on popular sensor data management and online collaborative systems. We then present the architecture for WikiSensing highlighting its main components and features. Several example scenarios are described to present the functionality of the system. We evaluate the approach by investigating the performance of aggregate queries and the scalability of the system.