bluuebunny/crossref_metadata_2025 huggingface dataset:
SUSCEPTIBILITY OF MONOSPECIES AND DUAL‐SPECIES BIOFILMS OF STAPHYLOCOCCUS AUREUS AND ESCHERICHIA COLI TO ESSENTIAL OILS
Authors: MILLEZI F.M. , PEREIRA M.O. , BATISTA N.N. , CAMARGOS N. , AUAD I. , CARDOSO M.D.G. , PICCOLI R.H.
Published: July 2012

The aim of this study was to investigate the susceptibility of Staphylococcus aureus and Escherichia coli biofilms formed on the polypropylene surface. The cultures were developed for 240 h, planktonic growth was characterized by colony‐forming unit (cfu)/mL and biofilms was characterized by quantifying biomass and cfu/cm2. Essential oils (EOs) of citronella and lemon were extracted by hydrodistillation and characterized by gas chromatography. Biofilm formation occured after 3 h of contact. In dual‐species biofilms, there was competition; S. aureus was the number of viable cells damaged by E. coli (P < 0.05). The EOs disinfectant action was similar in biofilms monospecies, viable cells and biomass decreased significantly. Dual‐species biofilms were more resistant to EOs. The action EOs on biofilm suggest promising alternatives to sanitize industrial polypropylene surfaces.

PRACTICAL APPLICATIONS

Historically, the majority of new drugs has been generated from natural products (secondary metabolites) and from compounds derived from natural products. The extracts of higher plants have been and still are widely used to obtain substances with antimicrobial action. However, their low concentration in the extract often makes the purification processes or the synergistic action of the different compounds unfeasible, causing major problems for industries. Seeking to reduce the parameters involved in the isolation and purification of compounds, these essential oils (EOs) have been studied. They present high antimicrobial efficiency, and in appropriate concentrations they are considered safe. The antimicrobial activity of EOs was showed that such substances can be used with sanitizing agents in industrial surfaces against bacterial biofilms. However, this line of research is still very new, so it is important to continue research for the development of industrial sanitizing with EOs.
Effect of Small Change in Oil Phase Composition on Rheological and Textural Properties of w/o Emulsion
Authors: Lukic Milica , Jaksic Ivana , Krstonosic Veljko , Dokic Ljubica , Savic Snezana
Published: July 2012

In this work, we have modified oil phase composition in one component (mineral oil, isocetyl palmitate, special Olive butter and dimethicone 200/350) and the aim of our work was to establish the influence of that alteration on emulsion rheological and textural properties. Additionally, continuous and oscillatory rheological measurements along with texture analysis were assessed in order to predict emulsion application behavior. Based on the obtained results, the change of oil phase has induced a change in the observed rheological and textural parameters and investigated samples can be divided into two distinct groups: the first group – samples with special Olive butter and dimethicone 200/350 and the second group – samples with isocetyl palmitate and mineral oil. Results confirmed that instrumental measurements, as sensitive tools, can be used in order to differentiate emulsions regarding textural properties and especially regarding their actual usage and sensory properties.

Practical Applications

It is a known fact that the structure of semisolid systems can be characterized by various rheological and textural parameters that are also apt to define certain sensory attributes. Sensory attributes dependent on structure characteristics and flow properties, used for the description of the product in pickup and rub‐out phase, could be predicted by instrumental, i.e., rheological and textural measurements. Expensive and time‐consuming studies performed with human panelists could be, at least to some extent, replaced with simple rheological and textural measurements. These findings could also contribute to the faster and easier introduction of new raw materials, regarding their characterization and prediction of their influence on the final product characteristics. A combined approach like this could be helpful as both time and money‐saving tool for full characterization of a novel consumer‐acceptable emulsion product.
Differences in Chewing Behavior during Mastication of Foods with Different Textures
Authors: Shiozawa Megumi , Taniguchi Hiroshige , Hayashi Hirokazu , Hori Kazuhiro , Tsujimura Takanori , Nakamura Yuki , Ito Kayoko , Inoue Makoto
Published: July 2012

The present study was designed to evaluate how typical Japanese staple foods – rice and rice cake – with different physical properties influence the patterns of muscle activity during chewing. Six normal adults were asked to eat rice and rice cake freely in a natural manner. Surface electromyographic recordings of the masseter and suprahyoid muscles were performed. There were large differences between the foods in terms of masticatory duration. The masseter activity per cycle was significantly greater for rice cake than for rice. The masseter activity gradually decreased as chewing progressed, although the suprahyoid activity did not change throughout the sequence of rice cake chewing. The results suggest that the process of bolus formation with rice cake is very different from that with rice in terms of jaw‐closing and jaw‐opening muscle activities.

Practical Applications

This study aimed to examine how the masticatory sequence adapts to variations in the initial properties of foods. This research may enhance our understanding of the oral physiology of bolus formation and changes in the physical properties of foods during chewing.
Tobacco Harm Reduction Advertising in the Presence of a Government‐Mandated Warning
Authors: CAPELLA MICHAEL L. , TAYLOR CHARLES R. , KEES JEREMY
Published: July 2012

Compelling research suggests that smokeless tobacco (SLT) products are safer than cigarettes, but awareness of this potential harm reduction alternative among consumers is low. Therefore, two between‐subjects experimental studies explore the potential for allowing the marketing of SLT as a “reduced‐risk” alternative to cigarette smoking. Specifically, this article addresses the issue of whether a harm reduction message with the simultaneous presence of the U.S. government‐mandated warning would: (1) change intentions of smokers to use SLT products; or (2) attract those who would not otherwise use any tobacco. Results suggest that an advertiser making a harm reduction statement in the presence of the warning leads to limited changes in consumers' risk perceptions of SLT products or intentions to try the product. Exposure to the experimental ads did not make nonsmokers significantly more likely to try SLT products, but also did not make smokers indicate that they were likely to switch to SLT products.
Statistics: how many?
Authors: Scott M. , Flaherty D. , Currall J.
Published: July 2012

The fourth in our series of articles on statistics for clinicians focuses on how we determine the appropriate number of subjects to include in an experimental study to provide sufficient statistical “power”.
Pharmacological options for intra‐operative and early postoperative analgesia: an update
Authors: Gurney M. A.
Published: July 2012

The motto of the 2011 Global Year Against Acute Pain was ‘Anticipate, Assess, Alleviate’. Recent advances in acute pain management include novel applications of widely used drugs, new techniques, as well as further development in our knowledge of pain scoring in veterinary patients. The concept of preventive analgesia is introduced here and serves to strengthen the widely accepted practice of pre‐emptive, multimodal analgesia.
Hypolipidemic Activity in Sprague–Dawley Rats and Constituents of a Novel Natural Vegetable Oil from Cornus Wilsoniana Fruits
Authors: Fu Jie , Zhang Xue‐Wei , Liu Kai , Li Qing‐Shan , Zhang Li‐Rong , Yang Xian‐Hui , Zhang Zhi‐Ming , Li Chang‐Zhu , Luo Yin , He Zhen‐Xiang , Zhu Hai‐Liang
Published: July 2012

Abstract:  Cornus wilsoniana Wanger is a woody oil plant distributed in the south region of the Yellow River, China. Its oil has been taken as edible oil for over 100 y, and consumption of such oil is believed to prevent hyperlipidemia in Chinese folk recipe. This study has investigated the hypolipidemic effect of Cornus wilsoniana oil (CWO) in Sprague–Dawley rats. The results demonstrated that CWO could significantly decrease total cholesterol (TC), total triacylglycerol (TG), and low‐density lipoprotein cholesterol (HDL‐C) in serum, liver weight, hepatic TC, and TG. After analyzing the chemical constituents of CWO, we found that the content of unsaturated fatty acids (UFA) was very high (69.12%). Specially, the n‐6 polyunsaturated fatty acids (PUFA), including linoleic acid, γ‐linolenic acid, and 11,14‐eicosadienoic acid, accounted very great proportion (38.86%). The high hypolipidemic activity of CWO might be attributed to the lipid‐lowering functions of these polyunsaturated fatty acids. Molecular docking was further performed to study the binding model of fatty acids (FA) from CWO to a possible hypolipidemic target, peroxisome proliferator‐activated receptor δ (PPARδ). The results showed that linoleic acid and γ‐linolenic acid could bind PPARδ very well.

Practical Application:  Cornus wilsoniana oil could be used as equilibrated dietary oil, not only having hypolipidemic function, but also helping to overcome essential fatty acids deficiency.
Top Food Sources Contributing to Vitamin D Intake and the Association of Ready‐to‐Eat Cereal and Breakfast Consumption Habits to Vitamin D Intake in Canadians and United States Americans
Authors: Hill Kathleen M. , Jonnalagadda Satya S. , Albertson Ann M. , Joshi Nandan A. , Weaver Connie M.
Published: July 2012

Abstract:  This study aimed to determine dietary vitamin D intake of U.S. Americans and Canadians and contributions of food sources to total vitamin D intake. Total of  7‐ or 14‐d food intake data were analyzed for vitamin D by a proprietary nutrient assessment methodology that utilized food intake data from the Natl. Eating Trends® service, portion size data from NHANES 1999–2004, and nutrient values using the Univ. of Minnesota's Nutrition Data System for Research software. Study participants were 7837 U.S. Americans and 4025 Canadians, ≥2‐y‐old males and females. The main outcome measures were total dietary vitamin D intake, percent contribution of foods to total vitamin D intake, and vitamin D intake by cereal and breakfast consumption habits. ANOVA was used to determine differences in means or proportions by age and gender and according to breakfast consumption habits. Mean vitamin D intake ranged from 152 to 220 IU/d. Less than 2% of participants in all age groups from the United States and Canada met the 2011 Recommended Daily Allowance (RDA) for vitamin D from foods. Milk, meat, and fish were the top food sources for vitamin D for both Americans and Canadians. Ready‐to‐eat (RTE) cereal was a top 10 source of vitamin D for Americans but not Canadians. Vitamin D intake was higher with more frequent RTE cereal and breakfast consumption in both countries, largely attributable to greater milk intake.

Practical Application:  Most U.S. Americans and Canadians do not meet the 2011 Inst. of Medicine recommended daily allowance (RDA) for vitamin D for their age groups from foods. Increasing breakfast and cereal consumption may be a useful strategy to increase dietary vitamin D intake to help individuals meet the RDA for vitamin D, particularly by increasing milk intake. However, it is likely that additional food fortification or vitamin D supplementation is required to achieve the RDA.
Expression of DnaJ Gene in Alicyclobacillus acidoterrestris under Stress Conditions by Quantitative Real‐Time PCR
Authors: Jiao Lingxia , Fan Mingtao , Hua Chengwei , Wang Shulin , Wei Xinyuan
Published: July 2012

Abstract:  This article describes the cloning, sequence analysis and expression of the DnaJ gene from Alicyclobacillus acidoterrestris. The genome walking technique was used to clone the full‐length sequence of DnaJ and quantitative real‐time PCR was used to analyze DnaJ expression under stress conditions. AadnaJ (GenBank accession nr: HQ893544) containing an open reading frame of 1137 bp encoding 378 amino acid residues was cloned from A. acidoterrestris DSM 3922T. The nucleotide sequence of AadnaJ shows 77% homology with the DnaJ of A. acidocaldarius LAA1. The DnaJ expression level was upgraded rapidly under heat or acid stress. Its mRNA expression level reached a peak value at 25 min after the onset of heat stress (70 °C) and at 1 h after the onset of acid stress (pH = 1). Acid stress at pH 1 for 25 and 60 min led to the DnaJ expression levels 2.1 times and 35.7 times above that of the control, respectively. In response to cold stress at 0 °C, the DnaJ expression level decreased drastically to 0.04 times that of the control level after 1 h. The expression patterns of DnaJ in response to the stress conditions shown here explained the heat and acidity endurance of A. acidoterrestris.

Practical Application:  This study directly addresses the role of the DnaJ gene in temperature and acid endurance in A. acidoterrestris. This provides a basis for the development of genetic and molecular techniques that may minimize the adverse effects of A. acidoterrestris in fruit juice production. This study also sheds light on the design of heat‐ and acid‐tolerant recombinases and the understanding of the molecular mechanisms underlying heat and acid resistance in A. acidoterrestris.
Inactivation Kinetics of Listeria monocytogenes by High‐Pressure Processing: Pressure and Temperature Variation
Authors: Doona Christopher J. , Feeherry Florence E. , Ross Edward W. , Kustin Kenneth
Published: July 2012

Abstract:  The enhanced quasi‐chemical kinetics (EQCK) model is presented as a methodology to evaluate the nonlinear inactivation kinetics of baro‐resistant Listeria monocytogenes in a surrogate protein food system by high‐pressure processing (HPP) for various combinations of pressure (P= 207 to 414 MPa) and temperature (T= 20 to 50 °C). The EQCK model is based on ordinary differential equations derived from 6 “quasi‐chemical reaction” steps. The EQCK model continuously fits the conventional stages of the microbial lifecycle: lag, growth, stationary phase, and death; and tailing. Depending on the conditions, the inactivation kinetics of L. monocytogenes by HPP show a lag, inactivation, and tailing. Accordingly, we developed a customized, 4‐step subset version of the EQCK model sufficient to evaluate the HPP inactivation kinetics of L. monocytogenes and obtain values for the model parameters of lag (λ), inactivation rate (μ), rate constants (k), and “processing time” (tp). This latter parameter was developed uniquely to evaluate kinetics data showing tailing. Secondary models are developed by interrelating the fitting parameters with experimental parameters, and Monte Carlo simulations are used to evaluate parameter reproducibility. This 4‐step model is also compared with the empirical Weibull and Polylog models. The success of the EQCK model (as its 4‐step subset) for the HPP inactivation kinetics of baro‐resistant L. monocytogenes showing tailing establishes several advantages of the EQCK modeling approach for investigating nonlinear microbial inactivation kinetics, and it has implications for determining mechanisms of bacterial spore inactivation by HPP.

Practical Application:  Results of this study will be useful to the many segments of the food processing industry (ready‐to‐eat meats, fresh produce, seafood, dairy) concerned with ensuring the safety of consumers from the health hazards of Listeria monocytogenes, particularly through the use of emerging food preservation technologies such as high‐pressure processing.
Exhaled nitric oxide monitoring does not reduce exacerbation frequency or inhaled corticosteroid dose in paediatric asthma: a randomised controlled trial
Authors: Pike Katharine , Selby Anna , Price Sophie , Warner John , Connett Gary , Legg Julian , Lucas Jane SA , Peters Sheila , Buckley Hannah , Magier Krzysztof , Foote Keith , Drew Kirsty , Morris Ruth , Lancaster Nikki , Roberts Graham
Published: July 2012

Introduction

Inhaled corticosteroid therapy (ICS) for asthma is currently modified according to symptoms and lung function. Fractional exhaled nitric oxide (FENO) has been demonstrated to be a non‐invasive marker of eosinophilic inflammation. Studies of FENO‐driven asthma management show variable success.

Objectives

This study aimed to evaluate whether monitoring FENO can improve outpatient management of children with moderate to severe asthma using a pragmatic design.

Methods

Children aged 6–17 years with moderate to severe asthma were recruited. Their asthma was stabilised before randomisation to FENO‐driven therapy or to a standard management group where therapy was driven by conventional markers of asthma control. ICS or long‐acting bronchodilator therapies were altered according to FENO levels in combination with reported symptoms in the FENO group. Participants were assessed 2 monthly for 12 months. ICS dose and exacerbation frequency change were compared between groups in an intention to treat analysis.

Results

Ninety children were randomised. No difference was found between the two groups in either change in corticosteroid dose or exacerbation frequency. Results were similar in a planned secondary analysis of atopic asthmatics.

Conclusion

FENO‐guided ICS titration does not appear to reduce corticosteroid usage or exacerbation frequency in paediatric outpatients with moderate to severe asthma. This may reflect limitations in FENO‐driven management algorithms, as there are now concerns that FENO levels relate to atopy as much as they relate to asthma control.
Dental care utilization among dentate adults with asthma: findings from the 2008 Behavioral Risk Factor Surveillance System
Authors: Parker Anthony J. , Yuen Hon K. , Slate Elizabeth H.
Published: July 2012

Objectives: This study investigated dental care service utilization among dentate adults with asthma and identified factors affecting dental care use among this population.

Methods: Data from 414,509 adults in the United States who participated in the 2008 Behavioral and Risk Factor Surveillance System were used to estimate the percentage of dentate adults with asthma who had at least one dental visit within the past year.

Results: The proportion of respondents with asthma who had at least one dental visit within the past year compared with the general population was significantly lower (67.4 percent versus 71.2 percent, P < 0.001 for dental visit for any reason; 64.3 percent versus 69.6 percent, P < 0.001 for dental cleaning). The adjusted odds of a dental visit for any reason within the past year for those with asthma were 0.86 [95% confidence interval (CI), 0.81‐0.91], and for dental cleaning 0.82 (95% CI, 0.78‐0.87) times that of those without asthma, respectively. Multivariable modeling showed dentate adults with asthma who are male, high school or less educated, unemployed, lower income, current smokers, and have lost more than six teeth were less likely to have a dental visit within the past year.

Conclusions: Compared with nonasthmatic individuals, dentate adults with asthma had a lower frequency of dental visits in the past year. Given a higher risk of oral disease among this population, heathcare providers should focus more effort on educating certain subgroups of patients with asthma on the importance of regular dental care.
Long‐term trends of coral imports into the United States indicate future opportunities for ecosystem and societal benefits
Authors: Rhyne Andrew L. , Tlusty Michael F. , Kaufman Les
Published: July 2012

The international trade in corals used to be primarily a curio trade of dried skeletons, but now focuses on live corals for the marine reef aquarium trade. The trade is still rapidly evolving, creating challenges including the addition of new species that outpace effective management strategies. New species in the live coral trade initially command high prices, but as they become common the price radically decreases with feedback effects to the trade. To understand these trends, 21 years of live coral import data for the United States were assessed. Trade increased over 8% per year between 1990 until the mid‐2000s, and has since decreased by 9% annually. The timing of the peak and decline varies among species, and is a result of the rising popularity of mini‐reef ecosystem aquariums, the global financial crisis, and an increase in aquaculture production. The live coral trade offers opportunities for coral reef ecosystem conservation and sustainable economic benefits to coastal communities, but realization of these externalities will require effective data tracking.
Spatial management of marine resources can enhance the recovery of predators and avoid local depletion of forage fish
Authors: Eero Margit , Vinther Morten , Haslob Holger , Huwer Bastian , Casini Michele , Storr‐Paulsen Marie , Köster Friedrich W.
Published: July 2012

The eastern Baltic cod stock has recently started to recover, after two decades of severe depletion, however with unexpected side effects. The stock has not re‐occupied its former wide distribution range, but remains concentrated in a limited area in the southern Baltic Sea. The biomass of forage fish, i.e., sprat and herring, is historic low in this area, which in combination with increasing cod stock results in locally high predation mortality of forage fish and cannibalism of cod. In line with low prey availability, body weight and nutritional condition of cod drastically declined. In the southern Baltic Sea, cod competes with pelagic fisheries for the limited resources of sprat and herring, while the largest biomass of these species is currently found outside the distribution range of cod. Accounting for spatial overlap between species is crucial in developing ecosystem based fisheries management to enhance the recovery of predator stocks.
Micropera tibetica sp. nov. (Orchidaceae) from southeastern Tibet, China
Authors: Lai Yang‐Jun , Jin Xiao‐Hua
Published: July 2012

A new species of Orchidaceae, Micropera tibetica from Medog County, Tibet, China, is described and illustrated. It is morphologically similar to M. mannii, from which it differs by having creamy white flowers, not twisted column, strongly oblique lateral sepals with emarginated apex, and very small lateral lobes of the lip.
Burnout and Vigor as Predictors of the Incidence of Hyperlipidemia among Healthy Employees
Authors: Shirom Arie , Toker Sharon , Melamed Samuel , Berliner Shlomo , Shapira Itzhak
Published: July 2012

We examined the effects of burnout and vigor on the incidence of hyperlipidemia. Based on the bivariate theoretical approach to negative and positive affects and on past studies on the prediction of blood lipids by burnout and vigor, we expected increases from Time 1 (T1) to Time 2 (T2) in burnout levels to be associated with an increase in the risk for hyperlipidemia and T1–T2 increases in vigor levels to be associated with a decrease in the risk of hyperlipidemia. Our sample consisted of 3,337 healthy employees (2,214 men and 1,123 women) who were followed up for about 27 months on average. Burnout and vigor were assessed by well‐validated multiple‐item instruments. We used logistic regressions and controlled for variables associated with blood lipids as well as with vigor and burnout. We cross‐validated all self‐reported hyperlipidemia by their T2 lipids levels. As expected, we found that T1–T2 increases in vigor levels were associated with a decreased risk of hyperlipidemia. However, the T1–T2 change in burnout levels was marginally significant (p = .06) in predicting hyperlipidemia. We consider our finding that vigor and burnout are independently associated with the risk of hyperlipidemia as providing support for the bivariate approach to affective states. In addition, our major finding suggests a possible mechanism via which vigor influences physical health outcomes.
Surgical treatment for bronchopleural fistula with omentum covering after pulmonary resection for non‐small cell lung cancer
Authors: Jiang Feng , Huang Jianfeng , You Qinjun , Yuan Fangliang , Yin Rong , Xu Lin
Published: July 2012

Background:  Bronchopleural fistula is an especially severe complication with a high mortality rate. We investigated the efficiency of our surgical treatments for this severe complication.

Methods:  From January 2007 to December 2009, standard surgical resections and systematic lymph node dissections for non‐small cell lung cancer (NSCLC) were performed on 1178 patients at our institution. Eight patients developed bronchopleural fistulas during the postoperative follow‐up period, and received reoperations. Seven patients underwent additional pneumonectomies, and the omental flap, which was mobilized using a transdiaphragmatic harvesting technique through the usual thoracotomy, was used to cover postpneumonectomy bronchial stump. The other patient, who had received right side pneumonectomy and systemic lymph node dissection, received omental flap stuffing and covering without reclosure of the stump or carinal plasty.

Results:  Bronchopleural fistulas after standard surgical resections and systematic lymph node dissections for NSCLC were observed in eight patients (0.68%) in our study. The period between pulmonary resection and the appearance of bronchopleural fistula ranged from eight to 19 days (median 11 days). Repairing of the bronchial fistula was successful in all eight patients and no development of late fistula was found during the follow‐up period. Postoperative hospital stay for undergoing omentoplasty to repair the bronchial fistula ranged between 11 and 23 days (median 15 days). There were no complications related to the omentoplasty procedure.

Conclusion:  Transdiaphragmatic harvesting technique of omental flap through a thoracotomy is safe and technically feasible. Surgical treatment for postoperative bronchopleural fistula with omental flap covering is effective.
Insect population curves: modelling and application to butterfly transect data
Authors: Soulsby Richard L. , Thomas Jeremy A.
Published: July 2012

1. Monitoring the abundance of insect populations is increasingly valuable to understand their population dynamics, plan management strategies and assess the attainment of conservation targets. As monitoring is often constrained in time and space, it is important to have a model of the temporal variation in numbers to enable limited field data to be fitted into a broader framework, and to estimate the total detectable population on a site. We use adult butterflies as a study system, because they are widely monitored, sensitive indicators of environmental change.

2. We derive a generic algebraic expression for the shape of the population curve that describes how the number of adult butterflies observed at a site varies through the flight period. This novel expression contains parameters corresponding to total detectable population, start‐date and length of eclosion period, and mean life span. These can be optimised to fit observed series of counts (e.g. butterfly transect data, moth light‐trap counts) for individual species, sites and years, using a reliable grid‐refinement optimisation procedure.

3. Assumptions about survivorship and death rate are supported by field observations of the life span of two species tested. The modelled population curve (POPFIT) closely fits observed transect data for three further species.

4. We give two simplified methods of estimating the total transect population: from the Index of Abundance and from the peak population. We discuss extrapolation of transect results to estimate total site population, taking account of observed sampling efficiencies.

5. Our new method compares favourably with previous models for assessing patterns of population change at monitored sites and can assist with the planning of optimal monitoring strategies. As well as population estimates, it allows standardised phenological parameters to be derived from field data and provides a standard curve for theoretical studies. The method is applicable to all insect species whose adults have distinct, non‐overwintering generations and to all other monitored organisms with similar demographies.
How differences in plant abundance measures produce different species‐abundance distributions
Authors: Anderson Barbara J. , Chiarucci Alessandro , Williamson Mark
Published: July 2012

1. Species‐abundance distributions (SADs) are a convenient and common method for describing ecological communities. Despite their long history and the cornucopia of theoretical models, which have been suggested to describe them, no agreement has been reached as to which models are best.

2. This lack of agreement is in part owing to the inherent differences in the abundance measure used. Discrete measures such as density and point quadrat cover produce a distinct veil line (positive skewness) when compared to continuous measures such as biomass or basal area. We compared two different sets of discrete and continuous abundance measures commonly used to estimate plant abundance, (i) cover (estimated from point quadrats) vs. biomass for 35 quadrats in garigue vegetation on serpentine soil in Tuscany, Italy; and (ii) density vs. basal area for the 2005 50 ha BCI (Panama) tree data. We used marginal plots (ordinary scatter plots with a dotplot of each variable along its own axis) to compare the shape of the SAD based on the two abundance measures.

3. The average of all 35 garigue plots gave a reasonably consistent description of the data. In contrast, when all 35 plots were concatenated, or when an individual plot was investigated, the discrete cover marginal plot, but not the continuous biomass plot, was truncated. The discrete density marginal plot, but not the continuous basal area plot was also truncated.

4. We highlighted the substantial effect that the species‐abundance measure selected has on the shape of the SAD by comparing measures of skewness and kurtosis. This suggests that communities sampled using different abundance methods may fit different theoretical models best, not because they are fundamentally different but because the abundance measure is fundamentally different. Averaging over all the quadrats produced a better correspondence between the two abundance methods. Aside from the theoretical aspects of model fitting, our results clearly show that comparisons of communities or meta‐analyses using SADs based on different measures of abundance should be treated with caution.
A Theoretical and Experimental Investigation of Unidirectional Freezing of Nanoparticle-Enhanced Phase Change Materials
Authors: Fan Liwu , Khodadadi J. M.
Published: July 2012

Highly-conductive nanostructures may be dispersed into phase change materials (PCM) to improve their effective thermal conductivity, thus leading to colloidal systems that are referred to as nanostructure-enhanced PCM (NePCM). Results of a theoretical and experimental investigation on freezing of NePCM in comparison to the base PCM are presented. A one-dimensional Stefan model was developed to study the unidirectional freezing of NePCM in a finite slab. Only the thermal energy equation was considered and the presence of static dispersed nanoparticles was modeled using effective media relations. A combination of analytical and integral methods was used to solve this moving boundary problem. The elapsed time to form a given thickness of frozen layer was therefore predicted numerically. A cooled-from-bottom unidirectional freezing experimental setup was designed, constructed, and tested. Thermocouple readings were recorded at several equally spaced locations along the freezing direction in order to monitor the progress of the freezing front. As an example, cyclohexane (C6H12) and copper oxide (CuO) nanoparticles were chosen to prepare the NePCM samples. The effective thermophysical and transport properties of these samples for various particle loadings (0.5/3.8, 1/7.5, and 2/14.7 vol. %/wt. %) were determined using the mixture and Maxwell models. Due to utilization of the Maxwell model for thermal conductivity of both phases, the numerical predictions showed that the freezing time is shortened linearly with increasing particle loading, whereas nonmonotonic expediting was observed experimentally. The maximum expediting was found to be nearly 8.23% for the 0.5 vol. % sample. In the absence of a nanoparticle transport model, the mismatch of the cold plate boundary conditions, lack of accurate thermophysical properties, especially in the solid phase of NePCM samples and precipitation issues with 2 vol. % samples were addressed by improving the experimental setup. Through adopting a copper cold plate, utilizing measured thermal conductivity data for both phases and using 1, 2, and 4 wt. % samples, good agreement between the experimental and numerical results were realized. Specifically, adoption of measured thermal conductivity values for the solid phase in the Stefan model that were originally underestimated proved to be a major cause of harmony between the experiments and predictions.
Chebyshev
Collocation Spectral Method for Three-Dimensional Transient Coupled Radiative–Conductive Heat
Transfer
Authors: Sun Ya-Song , Ma Jing , Li Ben-Wen
Published: July 2012

A Chebyshev collocation spectral method (CSM) is presented to solve transient coupled radiative and conductive heat transfer in three-dimensional absorbing, emitting, and scattering medium in Cartesian coordinates. The walls of the enclosures are considered to be opaque, diffuse, and gray and have specified temperature boundary conditions. The CSM is adopted to solve both the radiative transfer equation (RTE) and energy conservation equation in spatial domain, and the discrete ordinates method (DOM) is used for angular discretization of RTE. The exponential convergence characteristic of the CSM for transient coupled radiative and conductive heat transfer is studied. The results using the CSM show very satisfactory calculations comparing with available results in the literature. Based on this method, the effects of various parameters, such as the scattering albedo, the conduction–radiation parameter, the wall emissivity, and the optical thickness, are analyzed.
Spatial Generalizations of Planar Point-Angle and Path Generation Problems
Authors: Huang Chintien , Lai Ching-Lung
Published: July 2012

This paper deals with the spatial generalizations of two classical planar synthesis problems: the point-angle and the path generation problems. The two planar synthesis problems involve the guidance of a point through specified positions by using planar four-bar linkages. In spatial generalizations, we are concerned with the guidance of an infinitely extended line by using spatial 4C linkages. The equivalent screw triangle is used to derive the synthesis equations of the spatial 4C linkage. By constraining the translational motion in the driving C joint, the RCCC linkage is synthesized. Our results show that the synthesis of the 4C linkage for line guidance yields the same maximum number of positions as the planar four-bar linkage for point guidance. The maximum number of positions of the path generation of a line is nine, while that of the line-angle problem is five. In addition to presenting the spatial generalizations of planar synthesis problems, the results in this paper can be used to design spatial four-bar linkages to match line specifications, in which only a line element, such as a laser beam, is of interest.
Parameter Screening in Statistical Dynamic Computer Model Calibration Using Global Sensitivities
Authors: Drignei Dorin , Mourelatos Zissimos P.
Published: July 2012

Computer, or simulation, models are ubiquitous in science and engineering. Two research topics in building computer models, generally treated separately, are sensitivity analysis and computer model calibration. In sensitivity analysis, one quantifies the effect of each input factor on outputs, whereas in calibration, one finds the values of input factors that provide the best match to a set of test data. In this article, we show a connection between these two seemingly separate concepts for problems with transient signals. We use global sensitivity analysis for computer models with transient signals to screen out inactive input factors, thus making the calibration algorithm numerically more stable. We show that the computer model does not vary with respect to parameters having zero total sensitivity indices, indicating that such parameters are impossible to calibrate and must be screened out. Because the computer model can be computationally intensive, we construct a fast statistical surrogate of the computer model which is used for both sensitivity analysis and computer model calibration. We illustrate our approach with both a simple example and an automotive application involving a road load data acquisition (RLDA) computer model.
Parametric Analysis of Gear Mesh and Dynamic Response of Loaded Helical Beveloid Transmission With Small Shaft Angle
Authors: Song Chaosheng , Zhu Caichao , Lim Teik C. , Peng Tao
Published: July 2012

A synthesized gear mesh and dynamic model assuming line contact that is derived from a set of manufacturing parameters is formulated for analyzing the beveloid gear mesh-coupling mechanism. Using the proposed model, the effect of the dominant geometry design parameter that is the crossed angle between the first principal directions of the tooth surface curvatures (FPD-angle) on gear mesh characteristic and dynamic response is investigated. Also, the analysis of the gear mesh characteristic and dynamic response subject to torque load variation is performed. It is shown that the dynamic transmission error and dynamic mesh force worsen as the geometry FPD-angle increases for a specific torque load level. Furthermore, even though higher torque load can produce larger contact area, which is desirable, it also increases the gear mesh stiffness and transmission error that tend to aggravate dynamic response.
Metastable centers in AlGaN/AlN/GaN heterostructures
Authors: Polyakov Alexander Y. , Smirnov Nick B. , Govorkov A. V. , Kozhukhova E. A. , Pearton Stephen J. , Ren Fan , Karpov S. Yu. , Shcherbachev K. D. , Kolin N. G. , Lim Wantae
Published: July 2012

A set of AlGaN/AlN/GaN high electron mobility transistor structures with Al composition in the AlGaN barrier changing from 20% Al to 50% Al was grown by metalorganic chemical vapor deposition on sapphire and studied by capacitance-voltage (C-V) measurements, admittance spectroscopy, and deep level transient spectroscopy. C-V and admittance measurements were performed in the dark and after illumination. The results suggest the presence of high concentrations of deep negatively charged traps in the AlGaN barriers, producing shifts of the C-V characteristics to more positive voltages. The density of negatively charged centers can be increased by cooling at high reverse bias. These centers have a high barrier for the capture of electrons. Their thermal activation energy is estimated as 0.85 eV, while the optical ionization energy is ∼1.7 eV.
Structural characterization of He ion microscope platinum deposition and sub-surface silicon damage
Authors: Drezner Yariv , Greenzweig Yuval , Fishman Daniel , van Veldhoven Emile , Maas Diederik J. , Raveh Amir , Livengood Richard H.
Published: July 2012

In this paper we studied helium ion beam induced deposition (HIBID) of Pt on a silicon wafer using the recently commercialized helium ion microscope (HIM) at 25 kV and low beam currents. The motivation of this work was to understand the impact of light, inert helium ions on deposition rate and structure purity, with some implications on the usefulness of HIM nano-machining for circuit modification. Two Pt-rich deposits with sub-micron dimensions were grown with HIBID at different ion beam currents. The pillar and substrate structure were studied using bright and dark field TEM images. The authors analyzed metal purity profile of the HIBID deposit on height using energy dispersive x-ray spectroscopy. The maximum Pt content measured reached 41%, which is the highest measured metal content of a HIBID-grown structure. TEM studies of the sub-surface damage to the Si shows more damage below the deposit grown at a higher beam current. The differences in amorphization layer thickness between the two different beam currents are discussed. A comparison to Pt deposition by Ga FIB and electron beam induced deposition is provided, along with conclusions regarding the usage of HIBID technology for circuit modification.
Phase formation and film morphology of ultrathin Co1−xNixSi2 films
Authors: Zhu Zhiwei , Gao Xindong , Piao Yinghua , Hu Cheng , Qiu Zhijun , Zhang Zhi-Bin , Wu Dongping , Zhang Shi-Li
Published: July 2012

The formation of Co1−xNixSi2 films was investigated using Co1−xNix layers (1–8 nm thick, 1 ≥ x ≥ 0) sputter-deposited onto Si(100). The critical Co1−xNix thickness below which Co1−xNixSi2 films directly grow is found to be x-dependent; it increases from 1–2 nm for Co and Co0.75Ni0.25 to 4–6 nm for Co0.5Ni0.5, and from 3–4 nm for Ni to 6–8 nm for Co0.25Ni0.75. The Co1−xNixSi2 growth tends to occur at lower temperatures with decreasing t and/or increasing x. Although ultrathin, the Co1−xNixSi2 films can remain morphologically stable at 900 °C. Entropy of mixing coupled with lattice matching is discussed as being responsible for the enhanced Co1−xNixSi2 growth and stability.
THE UNBEARABLE BEINGNESS OF LIGHT — Dressingand Undressing Photonsin Black Hole Spacetimes
Authors: HOLLOWOOD TIMOTHY J. , SHORE GRAHAM M.
Published: July 2012

Gravitational tidal forces acting on the virtual e+e- cloud surrounding a photon endow spacetime with a nontrivial refractive index. This has remarkable properties unique to gravitational theories including superluminal low-frequency propagation, in apparent violation of causality, and amplification of the renormalized photon field, in apparent violation of unitarity. Using the geometry of null congruences and the Penrose limit, we illustrate these phenomena and their resolution by tracing the history of a photon as it falls into the near-singularity region of a black hole.
SECRET LIFE OF THE SPACETIME
Authors: PADMANABHAN T.
Published: July 2012

Just as the thermal properties of normal matter demands the existence of microscopic degrees of freedom, the thermal properties of null surfaces — perceived as local Rindler horizons by accelerated observers — demands the existence of microscopic degrees of freedom to spacetime. The distortion of the null surfaces, just like the deformation of an elastic solid, costs entropy. I show how, just like in the case of an elastic solid, one can describe the dynamics of the spacetime solid by introducing an entropy density to the distortion of null surfaces in the spacetime.
NEUTRINO OSCILLATION IN MATTER AND PARAMETERS s13, δCP
Authors: KISSLINGER LEONARD S. , HENLEY ERNEST M. , JOHNSON MIKKEL B.
Published: July 2012

We estimate the dependence of νμ to νe conversion on parameters θ13 and δ CP for several experimental facilities studying neutrino oscillations. We use the S-Matrix theory to estimate νe disappearance and compare estimates based on an older theory being used to extract θ13 from the Double Chooz, Daya Bay, and RENO data, to assist in extracting an accurate value for θ13 from these projects. We use values of θ13 within known limits, and estimate the dependence of νμ-νe CP violation (CPV) probability on δ CP in order to suggest new experiments to measure CPV for neutrinos moving in matter.
THE EFFECT OF TEMPERATURE ON SYNTHESIS AND CHARACTERIZATION OF BMN–BASE PIEZOELECTRIC THIN FILM PREPARED BY SPRAY PYROLYSIS
Authors: GHASEMIFARD M.
Published: July 2012

The 0.65Ba(Mg1/3,Nb2/3)O3-0.35BaTiO3 thin films was deposited on glass/aluminum substrates by using spray pyrolysis method. The effect of annealing temperature on perovskite phase and crystalline structure analysis of the BMN-BT films was performed on an X-ray diffraction (XRD). Surface morphology, roughness and particle size of the BMN-BT thin films was characterized with atomic force microscopy (AFM) and scanning electronic microscopy (SEM). Polarization hysteresis measurements was performed at different temperatures. From the P–E hysteresis loops one can observe the best temperature that led to improved properties of dielectric constant, polarization and piezoelectric coefficients were 600°C.
IMPACT OF SUBSIDY ON LOW-RENT HOUSING LESSEES' WELFARE IN CHINA
Authors: WU DI , GAO PENG , DONG JICHANG
Published: July 2012

Chinese Low-rent housing subsidy has been increasing year by year. However, it will be a very one-sided view if we only take the increasing number of subsidy into consideration when evaluating the effects of subsidy policy on low-rent housing lessees. Thus we studied on the impact of subsidy increase on low-rent housing lessees' welfare in China, and explored a valid way to evaluate the utility of the subsidy policy. At first, basing on the theory of welfare, we analyze the indifference curve model within consumption budget condition. After that, we applied the Cobb–Douglas utility function to establish a low-rent housing lessees' welfare model. Finally, some suggestions, especially in regard to the use of Information Technology to support subsidy making and protect low-rent housing lessees' welfare, are given to the Ministry of Housing and Urban–Rural Development of the People's Republic of China (MOHURD) and local Municipal Commissions of Housing and Urban–Rural Development (MCOHURD).
A NOVEL FRAMEWORK FOR MODELING VALUE FOR THE CUSTOMER, AN ESSAY ON NEGOTIATION
Authors: NICOLA SUSANA , FERREIRA EDUARDA PINTO , FERREIRA J. J. PINTO
Published: July 2012

This paper proposes a novel framework for modeling the Value for the Customer, the so-called Conceptual Model for Decomposing Value for the Customer (CMDVC). This conceptual model is first validated through an exploratory case study where the authors validate both the proposed constructs of the model and their relations. In a second step the authors propose a mathematical formulation for the CMDVC as well as a computational method. This has enabled the final quantitative discussion of how the CMDVC can be applied and used in the enterprise environment, and the final validation by the people in the enterprise. Along this research, we were able to confirm that the results of this novel quantitative approach to model the Value for the Customer is consistent with the company's empirical experience. The paper further discusses the merits and limitations of this approach, proposing that the model is likely to bring value to support not only the contract preparation at an Ex-Ante Negotiation Phase, as demonstrated, but also along the actual negotiation process, as finally confirmed by an enterprise testimonial.
ELASTIC PROPERTIES OF CNT-ENGINEERED POLYMER COMPOSITES USING MULTI-LEVEL MECHANICS APPROACH
Authors: JOSHI SUNIL C. , TOH WILLIAM
Published: July 2012

There has been increasing attention to utilizing carbon nanotubes (CNTs) as nano-fillers in polymers and polymer matrix composite materials, such as carbon fiber reinforced plastics. However, the understanding of how randomly oriented CNTs affect mechanical properties of such CNT-engineered composites is limited. This paper serves to develop an analytical model for determining the elastic properties of CNT-engineered composite materials using a mechanics of materials approach. Analysis of the properties was constructed progressively using material unit cells starting from the nano level, to the micro level, and finally, to the macro level. MATLAB programming platform was used to facilitate simulation of the modeling process. Typical simulation cases of the CNT-engineered composite materials are presented in comparison with published experimental and other data, where appropriate.