bluuebunny/crossref_metadata_2025 huggingface dataset:
Antithetic Time Series Analysis and the Companyx Data
Authors: Ridley Dennis , Ngnepieba Pierre
Published: December 2012

Antithetic time series analysis is the solution to a most perplexing problem in mathematical statistics. When a mathematical model is fitted to serially correlated data, the parameters of the model are unavoidably biased. All forecasts that are obtained from the model are unavoidably biased and therefore diverge. The forecast reliability worsens with the forecast horizon. It is shown that the forecast bias can be dynamically reduced. This is made possible by the entirely counterintuitive discovery of antithetic time series theory that permits unbiased forecast error convergence to a constant, independent of forecast origin. The forecast error variance in each time period is the same.
THE EFFECT OF MONETARY POLICY ON CREDIT SPREADS
Authors: Cenesizoglu Tolga , Essid Badye
Published: December 2012

We analyze the effect of monetary policy on yield spreads between corporate bonds with different credit ratings over the business cycle. We use futures contracts to distinguish between expected and unexpected changes in the Fed funds target rate and several indicators to distinguish between different phases of the business cycle. In line with the predictions of imperfect capital market theories, we find that yields on corporate bonds with low credit ratings widen (narrow) with respect to those with high credit ratings following an unexpected increase (decrease) in the Fed funds target rate during recession periods. Several tests suggest that our results are robust to outliers, potential endogeneity problems, empirical specification, control variables, countercyclical risk premium in futures, and alternative definitions of credit spreads and economic conditions.
Social Contagion of Risk Perceptions in Environmental Management Networks
Authors: Muter Bret A. , Gore Meredith L. , Riley Shawn J.
Published: December 2012

An important requisite for improving risk communication practice related to contentious environmental issues is having a better theoretical understanding of how risk perceptions function in real‐world social systems. Our study applied Scherer and Cho's social network contagion theory of risk perception (SNCTRP) to cormorant management (a contentious environmental management issue) in the Great Lakes Basin to: (1) assess contagion effects on cormorant‐related risk perceptions and individual factors believed to influence those perceptions and (2) explore the extent of social contagion in a full network (consisting of interactions between and among experts and laypeople) and three “isolated” models separating different types of interactions from the full network (i.e., expert‐to‐expert, layperson‐to‐layperson, and expert‐to‐layperson). We conducted interviews and administered questionnaires with experts (e.g., natural resource professionals) and laypeople (e.g., recreational and commercial anglers, business owners, bird enthusiasts) engaged in cormorant management in northern Lake Huron (n = 115). Our findings generally support the SNCTRP; however, the scope and scale of social contagion varied considerably based on the variables (e.g., individual risk perception factors), actors (i.e., experts or laypeople), and interactions of interest. Contagion effects were identified more frequently, and were stronger, in the models containing interactions between experts and laypeople than in those models containing only interactions among experts or laypeople.
Combining Experts: Decomposition and Aggregation Order
Authors: Baker Erin , Olaleye Olaitan
Published: December 2012

In this article we ask, if quantities in an elicitation have been decomposed, is it better to combine experts before or after recomposing the quantities? We find that combining experts earlier, before recomposition of the quantities, leads to smaller errors with less variance. A simulation shows that these differences may be quite small on average; while an application to actual data shows that the differences can be significant in individual decision problems.
Work–Family Conflict in Sri Lanka: Negotiations of Exchange Relationships in Family and at Work
Authors: Kailasapathy Pavithra , Metz Isabel
Published: December 2012

This study's aim is to understand how individuals who are part of dual‐earner couples experience and deal with work–family conflict in Sri Lanka. Twenty‐five interviews were conducted to identify if and how couples negotiated within their marital relationships, and between themselves and their supervisors, to reduce or cope with work–family conflict. The interviews indicated that negotiations at home and at work concerned contributions to the exchange relationship and were unlikely to adversely affect the (home or work) exchange relationships. Negotiations at home were more likely to be initiated by women than men. Further, the interviews revealed an influence of spouse's gender role ideology on the success of the negotiation at home. Negotiations at work were more likely to be initiated by the interviewees than by their supervisors. The results suggest that individuals in cultures with high power distance should still initiate negotiations when they feel it is possible to obtain favorable outcomes.
Translating Human Rights of the “Enemy”: The Case of Israeli NGOs Defending Palestinian Rights
Authors: Golan Daphna , Orr Zvika
Published: December 2012

This article explores the practices, discourses and dilemmas of the Israeli human rights NGOs that are working to protect and promote the human rights of Palestinians in the Occupied Territories. This case can shed light on the complex process of “triangular translation” of human rights, which is distinct from other forms of human rights localization studied thus far. In this process, human rights NGOs translate international human rights norms on the one hand, and the suffering of the victims on the other, into the conceptions and legal language commonly employed by the state that violates these rights. We analyze the dialectics of change and reproduction embedded in the efforts of Israeli activists to defend Palestinian human rights while at the same time depoliticizing their work and adopting discriminatory premises and conceptions hegemonic in Israeli society. The recent and alarming legislative proposals in Israel aimed at curtailing the work of human rights NGOs reinforce the need to reconsider the role of human rights NGOs in society, including their depoliticized strategies, their use of legal language and their relations with the diminishing peace movement.
Performing Regulation: Transcending Regulatory Ritualism in HIV Clinics
Authors: Heimer Carol A. , Gazley J. Lynn
Published: December 2012

Sociolegal scholars suggest that regulatory encounters often are occasions for displaying a surface compliance decoupled from day-to-day practice. Yet ethnographic data from five highly regulated HIV clinics show that regulatory encounters open opportunities both for ritualism and—surprisingly—for transcending ritualism. Using a theatrical analogy, we argue that improv performance is the technology that enables regulatory inspectors and clinic staff to transcend ritualism. As regulatory encounters unfold, clinics' carefully prepared performances sometimes change into more cooperative interactions where inspectors and regulatees hash out details about how rules will be applied and even work together on reports for the regulators' supervisors. By “performing together,” regulatory inspectors gain access to the clinic's backstage where they can assess clinic workers' deeper conformity to ethical and scientific norms. But such joint performances are less likely where cultural divides and material scarcity make it difficult for clinic staff to gain inspectors' trust.
Validity of Survey Response Propensity Indicators: A Behavior Genetics Approach
Authors: Littvay Levente , Popa Sebastian Adrian , Fazekas Zoltán
Published: December 2012

Objectives

This study explains how behavior genetic analysis using a twin design can help us assess the validity of our measures.

Methods

We test multiple indicators of response propensity, a measure used by survey researchers to better understand the similarities and differences between survey respondents and nonrespondents. The response propensity indicators evaluated include response to follow‐up surveys and subsequent waves of a panel and the completion of a sensitive recontact information sheet to aid subsequent recontact efforts.

Results

A classical and the newly proposed method of validation all point to insufficient validity of our response propensity measures. Construct validation using data from the National Survey of Midlife Development in the United States exhibited little correlation between indicators. Genetic analysis suggests that the success of subsequent data‐collection efforts is predominantly driven by additive genetic effects, while nonresponse to inquiries for recontact information is influenced predominantly by familial environmental predictors.

Conclusion

Our results indicate that different underlying constructs drive the response propensity indicators, suggesting that nonresponse is, at minimum, multidimensional.
Corruption or Insecurity? Understanding Dissatisfaction with Mexico’s Police
Authors: Sabet Daniel M.
Published: December 2012

Since at least 2005, Mexico has confronted a severe security crisis that threatens to undermine its rule of law and democracy. An effective police response has been hindered by frustrated citizens who do not report crime, come forward with information, serve as witnesses, or support their police. This foments a vicious cycle whereby insecurity and corruption foster dissatisfaction, which yields further insecurity and corruption. Breaking this cycle requires a better understanding of why citizens are dissatisfied with their police. One view holds that discontent is due to police corruption, but a somewhat rival perspective contends that citizens are primarily concerned with security outcomes. This study uses comparative survey data from 14 major Mexican cities to test these potentially rival approaches. It finds that both corruption and security outcomes matter, but direct experience with bribery has the single largest impact on dissatisfaction with the police.
Getting to Yes or Bailing on No: The Site Selection Process of Ethanol Plants in Wisconsin
Authors: Tigges Leann M. , Noble Molly
Published: December 2012

Prior studies of ethanol location rest on the assumption that ethanol producers are economic free agents—evaluating sites as if all counties are contenders for their business, weighing the availability of feedstocks along with their infrastructure needs, operating without ties to localities, and being subject to enticement from policy incentives. We analyze the political‐economic process through which ethanol plants come into communities by examining plant location decisions, plant financing, community receptivity toward the plant, local government incentives, and the dynamics of the approval process. We use case studies of ethanol plants in Wisconsin to explore the economic, social, and political dynamics of ethanol plant location. Our case studies provide evidence in support of some findings in the ethanol location literature—such as the importance of access to corn; however, they also suggest site selection criteria not adequately addressed by the literature. Furthermore, our data suggest that capital may not be as mobile as location theory assumes it to be and that location decisions are not primarily determined by consideration of profit maximization. Instead, the location of ethanol plants is greatly influenced by the extent to which the original initiators of the plant are locally embedded in its host community. Our research answers Barkley and McNamara's (:45) call for a return to a case studies approach in order to develop “reliable insights into the location process.”
Telocytes in the human kidney cortex
Authors: Qi Guisheng , Lin Miao , Xu Ming , Manole C. G. , Wang Xiangdong , Zhu Tongyu
Published: December 2012

Renal interstitial cells play an important role in the physiology and pathology of the kidneys. As a novel type of interstitial cell, telocytes (TCs) have been described in various tissues and organs, including the heart, lung, skeletal muscle, urinary tract, etc. (www.telocytes.com). However, it is not known if TCs are present in the kidney interstitium. We demonstrated the presence of TCs in human kidney cortex interstitium using primary cell culture, transmission electron microscopy (TEM) and in situ immunohistochemistry (IHC). Renal TCs were positive for CD34, CD117 and vimentin. They were localized in the kidney cortex interstitial compartment, partially covering the tubules and vascular walls. Morphologically, renal TCs resemble TCs described in other organs, with very long telopodes (Tps) composed of thin segments (podomers) and dilated segments (podoms). However, their possible roles (beyond intercellular signalling) as well as their specific phenotype in the kidney remain to be established.
Environmental and plant genetic effects on tri‐trophic interactions
Authors: Abdala‐Roberts Luis , Mooney Kailen A.
Published: December 2012

The effects of plant genotype and environmental factors on tri‐trophic interactions have usually been investigated separately, limiting our ability to compare the relative strength of these effects as well as their potential to interactively shape arthropod communities. We studied the interactions among the herb Ruellia nudiflora, a seed predator, and its parasitoids using 14 maternal plant families grown in a common garden. By fertilizing half of the plants of each family and subsequently recording fruit number, seed predator number, and parasitoid number per plant, we sought to compare the strength of plant genetic effects with those of soil fertility, and determine if these factors interactively shape tri‐trophic interactions. Furthermore, we evaluated if these bottom–up factors influenced higher trophic levels through changes in abundance across trophic levels (density‐mediated) or changes in the function of species interactions (trait‐mediated). Plant genetic effects on seed predators and parasitoids were stronger than fertilization effects. Moreover, we did not find plant genetic variation for fertilization effects on fruit, seed predator, or parasitoid abundance, showing that each factor acted independently on plant resources and higher trophic levels. Both bottom–up forces were transmitted via density‐mediated effects where increased fruit number from fertilization and plant genetic effects increased seed predator and parasitoid abundance; however, seed predator attack was density‐dependent, while parasitoid attack was density‐independent. Importantly, there was evidence (marginally significant in one case) that fertilization modified the function of plant‐seed predator and seed predator–parasitoid interactions by increasing the number of seed predators per fruit and decreasing the number of parasitoids per seed predator, respectively. These findings show that plant genetic and soil fertility effects cascaded up this simple food chain, that plant genetic effects were stronger across all trophic levels, and that these effects were transmitted independently and through contrasting mechanisms.
Factors Associated with Abortion‐Seeking and Obtaining a Safe Abortion in Ghana
Authors: Sundaram Aparna , Juarez Fatima , Bankole Akinrinola , Singh Susheela
Published: December 2012

Although Ghana's abortion law is fairly liberal, unsafe abortion and its consequences remain among the largest contributors to maternal mortality in the country. This study analyzes data from the 2007 Ghana Maternal Health Survey to identify the sociodemographic profiles of women who seek to induce abortion and those who are able to obtain safe abortion services. We hypothesize that women who have access to safe abortion will not be distributed randomly across different social groups in Ghana; rather, access will be influenced by social and economic factors. The results confirm this hypothesis and reveal that the women who are most vulnerable to unsafe abortions are younger, poorer, and lack partner support. The study concludes with policy recommendations for improving access to safe abortion for all subgroups of women, especially the most vulnerable.
Deep brain stimulation of the nucleus accumbens for the treatment of addiction
Authors: Müller Ulf J. , Voges Jürgen , Steiner Johann , Galazky Imke , Heinze Hans‐Jochen , Möller Michaela , Pisapia Jared , Halpern Casey , Caplan Arthur , Bogerts Bernhard , Kuhn Jens
Published: December 2012

Despite novel medications and other therapeutic strategies, addiction to psychotropic substances remains one of the most serious public health problems worldwide. In this review, beginning with an introduction of deep brain stimulation (DBS), we highlight the importance of the nucleus accumbens (NAc) in the context of the reward circuitry and addictive behavior. We will provide a short historic overview of other neurosurgical approaches to treat addiction and describe the experimental and preclinical data on DBS in addiction. Finally, we call attention to key ethical issues related to using DBS to treat addiction that are important for future research and the design of clinical trials.
Stability of Anthocyanin‐Rich W/O/W‐Emulsions Designed for Intestinal Release in Gastrointestinal Environment
Authors: Frank Kerstin , Walz Elke , Gräf Volker , Greiner Ralf , Köhler Karsten , Schuchmann Heike Petra
Published: December 2012

Abstract:  Anthocyanins belong to the most important hydrophilic plant pigments. Outside their natural environment, these molecules are extremely unstable. Encapsulating them in submicron‐sized containers is one possibility to stabilize them for the use in bioactivity studies or functional foods. The containers have to be designed for a target release in the human gastrointestinal system. In this contribution, an anthocyanin‐rich bilberry extract was encapsulated in the inner aqueous phase of water‐in‐oil‐in‐water‐double emulsions. The physical stability as well as the release of free fatty acids and encapsulated, bioactive substances from the emulsions during an in vitro gastrointestinal passage were investigated. The focus was on the influence of emulsion microstructural parameters (for example, inner and outer droplet size, disperse phase content) and required additives (emulsifier systems), respectively. It could be shown that it is possible to stabilize anthocyanins in the inner phase of double emulsions. The release rate of free fatty acids during incubation was independent of the emulsifier used. However, the exterior (O/W)‐emulsifier has an impact on the stability of multiple emulsions in gastrointestinal environment and, thus, the location of release. Long‐chained emulsifiers like whey proteins are most suitable to transport a maximum amount of bioactive substances to the effective location, being the small intestine for anthocyanins. In addition, it was shown that the dominating release mechanism for entrapped matter was coalescence of the interior W1‐droplets with the surrounding W2‐phase.

Practical Application:  Microencapsulation of phytochemicals and bioactives is in the focus of functional food development. Here, the influence of matrix material, formulation, and structural parameters on stabilization and release of the molecules encapsulated has to be known for target product and process design. As the results are representative for hydrophilic active ingredients encapsulated in double emulsion systems a cross‐sectoral use in the pharmaceutical sector is possible.
Phylogenetic position of Kontumia (Polypodiaceae) inferred from four chloroplast DNA regions
Authors: KIM Changkyun , ZHA Hong‐Guang , DENG Tao , SUN Hang , WU Su‐Gong
Published: December 2012

The phylogenetic position of the monotypic genus Kontumia (Polypodiaceae) is contentious. It has been suggested that Kontumia is related to Gymnogrammitis dareiformis (Drynarioideae) based on spore ornamentation and blade dissection, or it has been assigned as a member of microsoroid ferns (Microsoroideae) based on the shape of rhizome scales. In the present study, we determined the phylogenetic position of K. heterophylla using four chloroplast DNA regions (rbcL, atpB, rps4 + rps4‐trnS intergenic spacer [IGS], and trnL‐F IGS). A parsimony consensus tree indicated that K. heterophylla is not related to G. dareiformis, but is nested within the Leptochilus lineage of Microsoroideae. This relationship is also supported by sharing of clathrate scales on the rhizome, which is not found in G. dareiformis. Although marked morphological disparities are found between K. heterophylla and the Leptochilus lineage in terms of leaf dissection, fertile‐sterile leaf differentiation, and sori arrangement, our results indicate that these characters have evolved independently several times in Polypodiaceae.
Children's Judgments of Durations: A Modified Replication of Piaget's Study
Authors: Russell Kelly A. , Kamii Constance
Published: December 2012

One hundred students, 25 each in grades 2, 4, 6, and 8, were individually interviewed. A cylindrical beaker with five equidistant levels marked on it was presented first, and a pear‐shaped separation funnel was also presented. The funnel had a “faucet” at the bottom that allowed water to start and stop running into the beaker. The interviewer asked the child to mark the water levels on the funnel when the water had run to the first level in the beaker, to the second level, to the third level, and so on. The levels on the funnel thus varied a great deal depending on its diameter. The interviewer then asked, “Did the water take the same amount of time to go down from this level to the next in the funnel as it did to go up from this level to the next in the beaker?” It was found that correct judgments about durations were not made before eighth grade (the criterion being 75% of the eighth graders giving correct answers). This grade level was considerably later than the age of 7 or 8 (second grade) that Piaget reported.
Error propagation in biomass estimation in tropical forests
Authors: Molto Quentin , Rossi Vivien , Blanc Lilian
Published: December 2012

Reliable above‐ground biomass (AGB) estimates are required for studies of carbon fluxes and stocks. However, there is a huge lack of knowledge concerning the precision ofAGBestimates and the sources of this uncertainty. At the tree level, the tree height is predicted using the tree diameter at breast height (DBH) and a height sub‐model. The wood‐specific gravity (WSG) is predicted with taxonomic information and aWSGsub‐model. The tree mass is predicted using the predicted height, the predictedWSGand the biomass sub‐model.

Our models were inferred with Bayesian methods and the uncertainty propagated with a Monte Carlo scheme. The uncertainties in the predictions of tree height, treeWSGand tree mass were neglected sequentially to quantify their contributions to the uncertainty inAGB. The study was conducted in French Guiana where long‐term research on forest ecosystems provided an outstanding data collection on tree height, tree dynamics, tree mass and speciesWSG.

We found that the uncertainty in theAGBestimates was found to derive primarily from the biomass sub‐model. The models used to predict the tree heights andWSGcontributed negligible uncertainty to the final estimate.

Considering our results, a poor knowledge ofWSGand the height–diameter relationship does not increase the uncertainty inAGBestimates. However, it could lead to bias. Therefore, models and databases should be used with care.

This study provides a methodological framework that can be broadly used by foresters and plant ecologist. It provides the accurate confidence intervals associated with forestAGBestimates made from inventory data. When estimating region‐scaleAGBvalues (through spatial interpolation, spatial modelling or satellite signal treatment), the uncertainty of the forestAGBvalue in the reference forest plots has to be taken in account. We believe that in the light of the Reducing Emissions from Deforestation and Degradation debate, our method is a crucial step in monitoring carbon stocks and their spatio‐temporal evolution.
Understanding the relationship between dog ownership and children's physical activity and sedentary behaviour
Authors: Christian H. , Trapp G. , Lauritsen C. , Wright K. , Giles‐Corti B.
Published: December 2012

What is already known about this subject

Dog ownership is a catalyst for physical activity in adults.

Approximately 50–70% of Australian households with children have a dog.

Dog‐facilitated physical activity may be an effective way to increase physical activity and decrease child overweight and obesity.

What this study adds

Dog ownership was associated with self‐reported walking and physical activity, but not parent‐report screen use or measured weight status.

The results highlight the potential for dog ownership to significantly impact children's physical activity levels.

Within dog‐owning families, the promotion of walking and active play with a dog may be a strategy to increase children's physical activity and curb obesity.

Background

Dog ownership is a catalyst for physical activity in adults. Given 50–70% of Australian households with children have a dog, dog‐facilitated physical activity may be an effective way to increase physical activity and decrease child obesity.

Objective

We hypothesized that children with a family dog walk more, are more physically active and are more likely to achieve recommended levels of weekly physical activity compared with children who do not have a dog.

Method

Cross‐sectional data from the Western Australian TRravel, Environment, and Kids project (TREK) were analyzed for 1218 children aged 10–12 years. Individual and environment factors, child physical activity, walking, screen use, sedentary behaviour and dog ownership status was collected from child and parent questionnaires. Children's height and weight were measured.

Results

Approximately 60% of children had a family dog. Dog ownership was associated with, on average, 29 more minutes of walking and 142 more minutes of physical activity per week (P ≤ 0.01). After adjustment, children with a dog were 49% more likely to achieve the recommended level of weekly physical activity (420 min) and 32% more likely to have walked in their neighbourhood in the last week, compared with non‐dog owners (P ≤ 0.05). These relationships varied by gender. Dog ownership was not associated with screen use or weight status.

Conclusions

Dog ownership was associated with walking and physical activity, but not screen use or weight status. Within dog‐owning families, the promotion of walking and active play with a dog may be a strategy to increase children's physical activity.
The association between community‐level economic hardship and childhood obesity prevalence in Los Angeles
Authors: Shih M. , Dumke K. A. , Goran M. I. , Simon P. A.
Published: December 2012

What is already known about this subject

Neighbourhood social, economic and environmental factors are associated with childhood obesity.

Childhood obesity disproportionately impacts those living in low‐income neighbourhoods.

What this study adds

Childhood obesity prevalence is strongly associated with community‐level social and economic conditions as measured using a composite Economic Hardship Index.

Childhood obesity prevalence among communities in the highest hardship quartile was more than double the prevalence among communities in the lowest hardship quartile (26.9 vs. 12.5%).

The relationship between economic hardship and obesity differs by race/ethnicity.

Objective

The association between community‐level economic hardship and childhood obesity prevalence was examined in Los Angeles County, one of the largest and most racially and ethnically diverse regions in the United States.

Methods

Data from the 2008–2009 California Department of Education's Physical Fitness Testing Program were analyzed to assess obesity prevalence among 5th, 7th and 9th grade students attending public schools (n = 298 485). Community‐level socioeconomic conditions were compared using a census‐tract‐based Economic Hardship (EH) index. Mixed‐effects modelling was used to examine the association between obesity prevalence and gender, grade, race/ethnicity and EH.

Results

Higher community‐level EH was associated with higher childhood obesity prevalence (P < 0.001). The obesity prevalence among communities in the highest EH quartile (26.9%) was more than double the obesity prevalence among communities in the lowest EH quartile (12.5%). The slope of the association between EH and childhood obesity differed by racial/ethnic group. The slope was higher for non‐Hispanic White students, Hispanics, and non‐Hispanic Asians, and lower for non‐Hispanic Black students. Racial/ethnic disparities were observed across the socioeconomic spectrum.

Conclusions

Findings suggest that efforts to improve community socioeconomic conditions could reduce childhood obesity prevalence. Prevention efforts should target communities with high economic hardship and also focus on providing culturally relevant interventions that address disparities in obesity prevalence across communities.
No association between childcare and obesity at age 4 in low‐income Latino children
Authors: Zahir N. , Heyman M. B. , Wojcicki J. M.
Published: December 2012

Background

Previous studies have found an association between early entry to childcare and risk for overweight and obesity at 3 years of age. These studies, however, have been conducted primarily with higher income White populations or have found increased risk in the children of educated mothers.

Objective

To assess the relationship between timing of entry to childcare and duration of childcare and pediatric overweight and obesity in a high risk population.

Methods

Using data from a longitudinal cohort of low‐income Latino children in San Francisco, we evaluated the association between time of entry to childcare, hours in childcare, and risk for overweight and obesity at age 4. Similarly, we evaluated the relationship between these same childcare parameters and body mass index Z score and risk of having a waist circumference (WC) percentile ≥90th at 4 years of age.

Results

In contrast with previous studies, we found no association between being in childcare at 4 years of age or number of hours per week in childcare and risk for childhood overweight, obesity or WC ≥90th percentile at age 4. Additionally, we found no association between age of entry to childcare (≤6 months or ≤12 months of age) with risk for overweight or obesity at age 4. Future studies need to further evaluate the differential impact of childcare on early childhood obesity in relation to race/ethnicity and lower socioeconomic status.

Conclusion

Low‐income children may not be at increased risk for obesity in relation to early childcare exposure.
Oxidation Transitions for SiC Part I. Active‐to‐Passive Transitions
Authors: Jacobson Nathan , Harder Bryan , Myers Dwight
Published: December 2012

Oxidation of SiC can occur in a passive mode where a protective film is generated or in an active mode where a volatile suboxide is generated and can lead to rapid material consumption. The transition between these two modes of oxidation is a critical issue. Evidence indicates that this transition occurs via a different mechanism for the active‐to‐passive transition as compared with that of the passive‐to‐active transition. In Part I of this article, the former (active‐to‐passive mode) is explored. Three different types of SiC are examined: Si‐rich SiC, stoichiometric SiC, and C‐rich SiC. Evidence suggests that the SiO2/SiC equilibrium requirements as well as formation of SiO(g) at the SiC surface and subsequent oxidation to SiO2(s) are critical issues in the active‐to‐passive transition.
Effects of Tm3+ Additions on the Crystallization of LaF3 Nanocrystals in Oxyfluoride Glasses: Optical Characterization and Up‐Conversion
Authors: de Pablos‐Martín A. , Ristic D. , Bhattacharyya S. , Höche Th. , Mather G.C. , O Ramírez M. , Soria S. , Ferrari M. , Righini G.C. , Bausá L.E. , Durán A. , Pascual M.J.
Published: December 2012

The influence of the addition of 1 mol% Tm2O3 on the nanocrystallization of LaF3 in a glass of composition 55SiO2–20Al2O3–15Na2O–10LaF3 (mol%) has been studied. Tm2O3 affects the phase separation in the glass and delays the onset of crystallization with respect to the undoped glass. Additionally, the maximum LaF3 crystal size is slightly greater than that in the undoped glass–ceramics. The microstructural and compositional changes in the glass matrix have been studied using several techniques, including viscosity, dilatometry, X‐ray and neutron diffraction (XRD, ND), quantitative Rietveld refinement, transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and Raman spectroscopy. Photoluminescence measurements indicate that the Tm3+ ions are distributed between the glassy matrix and LaF3 crystals. Eu2O3 has been used as structure probe and part of the Eu3+ ions are reduced to Eu2+ when incorporated in the LaF3 nano‐crystals. Up‐conversion spectra under IR‐excitation show a higher intensity of the blue emission in the Tm‐doped glass–ceramic compared with that in the glass.
The Role of Schedule Mismatch in Ending Inventory Decisions in the Presence of Price Cuts
Authors: Chung Wenming , Narasimhan Ram , Talluri Srinivas
Published: December 2012

In the high‐tech sector, component suppliers are often able to offer preannounced price cuts (price markdowns) to manufacturers due to technological innovation that allows them to produce the existing components at lower costs. In this context, manufacturers (buyers) are primarily concerned with their existing inventory carried beyond the price cuts in order to lower inventory costs. In this research, we develop a newsvendor‐based decision model for this problem based on our experience in industry and a focal case study environment. Specifically, we consider the issue of delivery and demand uncertainties, and the interplay of the buying firm's operating hours and the transportation carrier's delivery hours, which combine to influence inventory costs and order fulfillment. We illustrate the results with numerical examples and sensitivity analyses, using a real world data set. We found that stockout cost plays a critical role in the ending inventory decisions. Lowering stockout cost will benefit buyers from lower risk of obsolescence costs.
Survey of dental radiographical practice in States of Punjab and Haryana in India
Authors: Sheikh Soheyl , Pallagatti Shambulingappa , Singla Isha , Gupta Rajesh , Aggarwal Amit , Singh Ravinder , Gupta Deepak
Published: December 2012

Background

Radiographs are used extensively in dentistry to supplement the clinical examination of the patients. Technical advances in X‐ray equipment and imaging systems have allowed significant reduction in radiation doses of patients during intraoral and extraoral radiography.

Objectives

The aim of this study was to determine the level of awareness of dental professionals of northern India regarding dose‐reduction techniques and radiographic equipment.

Methods

The survey covered 370 dentists in the states of Punjab and Haryana in northern India. Information on the demographic characteristics of the dentists, radiographic equipment, techniques, and radiation protection was obtained with a 30‐point questionnaire.

Results

The respondents knowledge concerning the technical details of their equipment was limited, with 82.3% not being aware about the kilovoltage peak of their machine. Up to 10.8% dentists were not aware about the speed of film. The most preferred technique for periapical radiography was the bisecting angle technique, which was used by 94.1% dentists.

Conclusion

In the present study the results indicate that for minimizing any unnecessary radiation, attempts should be made to improve dentists' knowledge about radiation‐dose‐reduction techniques.
Cryotherapy reduces skeletal muscle damage after ischemia/reperfusion in rats
Authors: Puntel Gustavo O. , Carvalho Nélson R. , Dobrachinski Fernando , Salgueiro Andréia C. F. , Puntel Robson L. , Folmer Vanderlei , Barbosa Nilda B. V. , Royes Luiz F. F. , Rocha João Batista T. , Soares Félix A. A.
Published: December 2012

The aim of this study was to analyze the effects of cryotherapy on the biochemical and morphological changes in ischemic and reperfused (I/R) gastrocnemius muscle of rats. Forty male Wistar rats were divided into control and I/R groups, and divided based on whether or not the rats were submitted to cryotherapy. Following the reperfusion period, biochemical and morphological analyses were performed. Following cryotherapy, a reduction in thiobarbituric acid‐reactive substances and dichlorofluorescein oxidation levels were observed in I/R muscle. Cryotherapy in I/R muscle also minimized effects such as decreased cellular viability, levels of non‐protein thiols and calcium ATPase activity as well as increased catalase activity. Cryotherapy also limited mitochondrial dysfunction and decreased the presence of neutrophils in I/R muscle, an effect that was corroborated by reduced myeloperoxidase activity in I/R muscle treated with cryotherapy. The effects of cryotherapy are associated with a reduction in the intensity of the inflammatory response and also with a decrease in mitochondrial dysfunction.
Melatonin improved rat cardiac mitochondria and survival rate in septic heart injury
Authors: Zhang Hongmin , Liu Dawei , Wang Xiaoting , Chen Xiukai , Long Yun , Chai Wenzhao , Zhou Xiang , Rui Xi , Zhang Qing , Wang Hao , Yang Quanhui
Published: December 2012

The pathogenesis of septic myocardial depression is complicated. Mitochondrial dysfunction has been suggested to be one of the main reasons for the reduced cardiac function. As melatonin is an antioxidant with the potential to scavenge radicals in mitochondria, we therefore employed a sepsis model, that is, cecal ligation and double puncture (CLP) in rats, to study the melatonin effects on: (i), myocardial mitochondrial function; (ii), heart systolic function; and (iii), prognosis of septic rats. We demonstrate that melatonin treatment (30 mg/kg, 3, 6, 12, 18, 24 hr after CLP) (i) improved myocardial cytochrome c oxidase (CcOX) activity and blood lactate level, (ii) attenuated heart dysfunction with a higher left ventricular ejection fraction (EF), and (iii) promoted 48‐h survival of the rats compared to CLP animals with no melatonin treatment. In conclusion, our results show that rat myocardial mitochondrial CcOX activity was depressed during severe sepsis accompanied by myocardial depression characterized by the decline of EF. In septic rats, melatonin increased the CcOX activity, improved heart systolic function, and lowered mortality rate. The clinical use of melatonin in septic myocardial depression should be tested in the future.
The role of physiological markers of health in the association between demographic factors and periodontal disease
Authors: Levine M. E. , Kim J. K. , Crimmins E. M.
Published: December 2012

Background and Objective

Age is highly related to oral health status. The higher prevalence of oral disease within subgroups of the population may reflect a tendency towards “early aging” and dysregulation of multiple physiological systems. This study examines whether the association between periodontal disease and demographic factors is mediated by physiological measures of health.

Material and Methods

Logistic regression was used to examine whether biomarkers and demographic factors, such as socio‐economic status (SES) and race/ethnicity, were associated with periodontal disease, and then whether the strength of these relationships could be attributed to associations between demographic variables and physiological measures of systemic health.

Results

Periodontal disease was associated with measures of SES and race/ethnicity. Furthermore, 1‐unit increases in cytomegalovirus (CMV), optical density, C‐reactive protein (CRP) and glycated hemoglobin (HbA1c) were associated with a 25% [odds ratio (OR) = 1.25; 95% confidence interval (CI): 1.14–1.36], 13% (OR = 1.13; 95% CI = 1.03–1.24) and 19% (OR = 1.19; 95% CI = 1.12–1.27) increased likelihood of periodontal disease, respectively. However, when biomarkers and socio‐demographic variables were both included in the model, their associations with periodontal disease were significantly reduced or eliminated.

Conclusions

The risk of periodontal disease is higher among black and/or low‐income individuals; however, these associations appear to be partly due to the greater probability of elevated levels of CRP, CMV or HbA1c among these groups.
Functional implications of the intertarsal joint shape in a terrestrial (Coturnix coturnix) versus a semi‐aquatic bird (Callonetta leucophrys)
Authors: Provini P. , Simonis C. , Abourachid A.
Published: December 2012

As birds have a diversity of locomotor behaviors, their skeleton is subjected to a variety of mechanical constraints (gravitational, aerodynamic and sometimes hydrodynamic forces). Yet, only minor modifications in post‐cranial skeleton shape are observed across the diversity of avian species in comparison with other vertebrates. The goal of this study was to explore potential morphological adjustments that allow locomotion in different habitats in Anatidae. Specifically, we compared a strictly terrestrial bird, the common quail Coturnix coturnix, and a semi‐aquatic bird, the ringed teal Callonetta leucophrys, to explore whether their anatomy reflects the constraints of locomotion in different habitats (water vs. land). We compared the tibiotarsus and the tarsometatarsus shape between the two species using a geometric morphometric approach. Our data illustrate distinct differences between species with a more medially oriented intertarsal joint in the ringed teal than in the common quail, which may be linked to the kinematics of walking and paddling. This study lays the foundations to understand the functional requirements for moving in both terrestrial and aquatic environments in Anatidae, and suggests morphological characteristics of the bird hindlimb skeleton that may help to predict the motions it is capable of.
Geographical distribution and ecological diversification of South American octodontid rodents
Authors: Ojeda A. A. , Novillo A. , Ojeda R. A. , Roig‐Juñent S.
Published: December 2012

Caviomorph rodents represent one of the most distinctive groups of mammals in southern South America drylands; they colonized South America from Africa via trans‐oceanic dispersions in the Eocene (40–50 Ma) and underwent an extraordinary ecological radiation after their arrival, thus making this group of great interest for biogeographic and evolutionary studies. The aim of this article was to provide a working hypothesis regarding the biogeographical history and ecological diversification of one of its conspicuous families, the Octodontidae. We reconstruct the evolutionary theater where their ecological diversification took place, and potential events of dispersal, vicariance and extinctions. We analyzed the historical biogeography of the Octodontidae across the eight ecoregions where they occur, based on species phylogeny and divergence times. Four approaches were used to reconstruct ancestral area: (1) Statistical Dispersal–Vicariance Snalysis (S‐DIVA); (2) Bayesian binary Markov chain Monte Carlo (MCMC) analysis implemented in Reconstruct Ancestral State in Phylogenies (RASP); (3) Fitch optimization method; and (d) weighted ancestral area analysis (WAAA). Parsimony ancestral state reconstructions were implemented in order to explore the evolutionary history of an ecological character, mode of life. We propose the northern portion of the Monte desert ecoregion as the ancestral area in the evolution of the Octodontidae, with subsequent dispersal and enlargement of the family geographic range. The evolution of their ecological specialization (i.e. modes of life) suggests an ambiguous ancestral condition (saxicolous, generalist terrestrial, semifossorial) linked to species adaptation to arid environments, with fossoriality appearing later in octodontid evolution. The evolution of the Octodontidae is associated with contrasting environmental conditions (i.e. climate and vegetation) produced by the Andean Uplift between eastern and western sides.
Inverting the Panopticon: Google Earth, Wonder and Earthly Delights
Authors: Mittman Asa
Published: December 2012

This essay considers the user experience of Google Earth, comparing the world it presents with other world views including static print maps, medieval mappaemundi, and Hieronymus Bosch’s Garden of Earthly Delights. It also considers the scopic environment of Google Earth in relation to Jeremy Bentham’s Panopticon, a theoretical prison design intended to provide a single guard the ability to view every inmate while remaining unobserved. The Google Earth interface generates wonder and geographic longing, but also empowers the user by granting new and flexible controls that differ from those available to users of print and manuscript maps. Ultimately, Google Earth is not an application that provides great utility, as traditionally defined – it does not help us navigate the physical world. Instead, it does something much more powerful: it gives us a new way to contemplate the world in which we live.
Kinetics and prediction of HBsAg loss during therapy with analogues in patients affected by chronic hepatitis B HBeAg negative and genotype D
Authors: Boglione Lucio , D'Avolio Antonio , Cariti Giuseppe , Gregori Gabriella , Burdino Elisa , Baietto Lorena , Cusato Jessica , Ghisetti Valeria , De Rosa Francesco G. , Di Perri Giovanni
Published: December 2012

Background & Aims

In patients affected by chronic hepatitis because of HBV infection, long‐term suppressive therapy with nucleos(t)ides analogues in the HBeAg− patients has shown low effects on HBsAg titre (qHBsAg) decrease, and HBsAg loss is difficult to achieve. Thus, in this type of patients the main goals of antiviral therapy is the suppression of HBV‐DNA and ALT normalization.

Methods

We retrospectively evaluated different qHBsAg kinetics in 134 treatment‐naïve patients having the same characteristics: HBeAg‐, infection sustained by HBV genotype D and persistently undetectable HBV‐DNA. Patients were treated with NAs therapy (lamivudine, adefovir, telbivudine, entecavir and tenofovir) for at least 2 years. qHBsAg was performed every 6 months.

Results

Our results showed a significantly greater qHBsAg decline after 2 years in patients treated with tenofovir (0.45 logIU/ml) than in patients treated with telbivudine (0.12 logIU/ml; P < 0.001). The calculated expected time to HBsAg loss was shorter in the tenofovir group than in the telbivudine group (nearly 17 vs 63 years, P < 0.001).

Conclusions

HBeAg negative patients infected by HBV genotype D should be treated with more potent NAs such as entecavir or tenofovir to obtain a significant qHBsAg decrease, but the achievement of HBsAg loss seems to require almost two decades of therapy.