bluuebunny/crossref_metadata_2025_split huggingface dataset:
DNA damage in normally and prematurely aged mice
Authors: Maslov Alexander Y. , Ganapathi Shireen , Westerhof Maaike , Quispe‐Tintaya Wilber , White Ryan R. , Van Houten Bennett , Reiling Erwin , Dollé Martijn E. T. , van Steeg Harry , Hasty Paul , Hoeijmakers Jan H. J. , Vijg Jan 
Published: March 2013

SummarySteady‐state levels of spontaneous DNA damage, the by‐product of normal metabolism and environmental exposure, are controlled by DNA repair pathways. Incomplete repair or an age‐related increase in damage production and/or decline in repair could lead to an accumulation of DNA damage, increasing mutation rate, affecting transcription, and/or activating programmed cell death or senescence. These consequences of DNA damage metabolism are highly conserved, and the accumulation of lesions in the DNA of the genome could therefore provide a universal cause of aging. An important corollary of this hypothesis is that defects in DNA repair cause both premature aging and accelerated DNA damage accumulation. While the former has been well‐documented, the reliable quantification of the various lesions thought to accumulate in DNA during aging has been a challenge. Here, we quantified inhibition of long‐distance PCR as a measure of DNA damage in liver and brain of both normal and prematurely aging, DNA repair defective mice. The results indicate a marginal, but statistically significant, increase in spontaneous DNA damage with age in normal mouse liver but not in brain. Increased levels of DNA damage were not observed in the DNA repair defective mice. We also show that oxidative lesions do not increase with age. These results indicate that neither normal nor premature aging is accompanied by a dramatic increase in DNA damage. This suggests that factors other than DNA damage per se, for example, cellular responses to DNA damage, are responsible for the aging phenotype in mice.
A Joint Regression Analysis for Genetic Association Studies with Outcome Stratified Samples
Authors: Wu Colin O. , Zheng Gang , Kwak Minjung 
Published: March 2013

AbstractSummaryGenetic association studies in practice often involve multiple traits resulting from a common disease mechanism, and samples for such studies are often stratified based on some trait outcomes. In such situations, statistical methods using only one of these traits may be inadequate and lead to under‐powered tests for detecting genetic associations. We propose in this article an estimation and testing procedure for evaluating the shared‐association of a genetic marker on the joint distribution of multiple traits of a common disease. Specifically, we assume that the disease mechanism involves both quantitative and qualitative traits, and our samples could be stratified based on the qualitative trait. Through a joint likelihood function, we derive a class of estimators and test statistics for evaluating the shared genetic association on both the quantitative and qualitative traits. Our simulation study shows that the joint likelihood test procedure is potentially more powerful than association tests based on separate traits. Application of our proposed procedure is demonstrated through the rheumatoid arthritis data provided by the Genetic Analysis Workshop 16 (GAW16).
The effect of chronic twice daily exenatide treatment on β‐cell function in new onset type 2 diabetes
Authors: Gastaldelli Amalia , Brodows Robert G. , D'Alessio David 
Published: March 2013

AbstractObjectiveTo determine the effect of chronic daily exenatide treatment on β‐cell function in type 2 diabetes (T2DM).BackgroundGlucagon‐like peptide receptor agonists, such as exenatide, are commonly used to treat patients with T2DM. Drugs in this class are insulinotropic but lower blood glucose by multiple mechanisms such that effects on β‐cell function can be difficult to discern by conventional measures.DesignSeventy‐nine subjects with previously untreated T2DM were studied before and after 24 weeks of treatment with one of the two doses of exenatide, 5‐ or 10‐μg twice daily, or placebo. All subjects had oral glucose tolerance tests (OGTT) before and after randomization with measurement of plasma glucose, insulin and C‐peptide concentrations. Insulin secretion rates (ISR), peripheral insulin sensitivity (OGIS) and hepatic insulin resistance index (Hep‐IR) were calculated.ResultsDuring the trial, all three groups lost similar, small but significant, amounts of weight. Compared to placebo, 24 weeks of daily high‐ or low‐dose exenatide treatment reduced HbA1c and improved fasting and postprandial hyperglycaemia. Exenatide was associated with improved OGIS and Hep‐IR independent of changes in weight. Plasma insulin levels and ISR during the OGTT did not differ before or after treatment with exenatide or placebo. However, when considered as a function of plasma glucose and insulin sensitivity, both doses of exenatide improved ISR proportionately to the improvement in plasma glucose. The higher dose of exenatide was associated with a significant improvement in β‐cell sensitivity to glucose.ConclusionsThese findings demonstrate that in persons with early T2DM, chronic treatment with exenatide enhanced ISR and increased β‐cell sensitivity to glucose. These improvements in β‐cell function were not clearly reflected in plasma insulin and C‐peptide levels, but became apparent when glycemia and insulin sensitivity were accounted for.
Active Tactile Sensibility of Single‐Tooth Implants versus Natural Dentition: A Split‐Mouth Double‐Blind Randomized Clinical Trial
Authors: Kazemi Mahmoud , Geramipanah Farideh , Negahdari Ramin , Rakhshan Vahid 
Published: March 2013

AbstractBackgroundUnlike passive sensitivity of implants/teeth that is assessed more, only three controversial studies have compared active tactile sensibility (ATS) of implants and teeth.PurposeWe aimed to explore the difference between the ATS of teeth and single‐tooth implants.MethodsThe ATS of single‐tooth implants and contralateral teeth was measured in 25 patients after they bit on gold and placebo foils 0‐ to 70‐μm thick, each for five times, in a random order blinded to patients and assessor, carried out at two sessions. Based on the experimental range of 0 μm (mock trials) to 70 μm, the sigmoid shape of psychometric curve was estimated to locate the 50% values as the ATS thresholds for each tooth or implant. ATS Data were analyzed using paired and unpaired t‐tests and multiple linear regression (α = 0.05, β ≤ 0.1). Also, equivalence testing approach was used to assess semi‐objectively the clinical significance.ResultsAverage ATS values for teeth and implants were 21.4 ± 6.55 μm and 30.0 ± 7.55 μm, respectively (p = .0001 [paired t‐test]). None of the geometric characteristics of implants nor duration of implant in function were correlated with the ATS (p > .4 [regression]). Age was positively associated with the ATS of both implants and teeth (p ≤ .019 [regression]). Tooth ATS (but not implant ATS) was significantly higher in males compared with females (p = .050 [unpaired t‐test]), which contributed to a generalizable tooth‐implant difference higher than 8‐μm clinical equivalence margin in females. The ATS was not significantly different between arches or between anterior/posterior regions (p > .6).ConclusionThere was a slight but statistically significant difference between implant and tooth tactile sensitivities.
Constructing a New Theory From Old Ideas and New Evidence
Authors: Rhodes Marjorie , Wellman Henry 
Published: March 2013

AbstractA central tenet of constructivist models of conceptual development is that children's initial conceptual level constrains how they make sense of new evidence and thus whether exposure to evidence will prompt conceptual change. Yet little experimental evidence directly examines this claim for the case of sustained, fundamental conceptual achievements. The present study combined scaling and experimental microgenetic methods to examine the processes underlying conceptual change in the context of an important conceptual achievement of early childhood—the development of a representational theory of mind. Results from 47 children (M age = 3.7 years) indicate that only children who were conceptually close to understanding false belief at the beginning of the study, and who were experimentally exposed to evidence of people acting on false beliefs, reliably developed representational theories of minds. Combined scaling and microgenetic data revealed how prior conceptual level interacts with experience, thereby providing critical experimental evidence for how conceptual change results from the interplay between conceptions and evidence.
A Paradox for Conservation: Electricity Pylons May Benefit Avian Diversity in Intensive Farmland
Authors: Tryjanowski Piotr , Sparks Tim H. , Jerzak Leszek , Rosin Zuzanna M. , Skórka Piotr 
Published: March 2013

AbstractOver the past century, electricity power lines have been a conspicuous part of the European landscape. These structures are generally known to cause fatalities to birds. However, some bird species use electricity poles as nesting structures, song posts, or for perching. Other, but not‐acknowledged, benefits probably include the marginal habitats around the base of pylons. We tested differences in breeding bird communities under pylons, under electricity high‐voltage power lines, and in adjacent open fields. Birds were counted twice during the 2011 breeding season in a total of 91 study plots located in the intensive farmland of western Poland. Both species number and bird abundance were significantly higher under pylons and under power lines at control points than in open fields, especially where there were shrubs under the pylons. Pylons and power lines locally may play a positive role for the avian community in intensive farmland, especially if vegetation succession under pylons is allowed to develop to the shrub stage.
Understanding the Determinants of Volunteer Retention Through Capture‐Recapture Analysis: Answering Social Science Questions Using a Wildlife Ecology Toolkit
Authors: Beirne Christopher , Lambin Xavier 
Published: March 2013

AbstractScientists and conservationists increasingly rely on contributions by volunteers recruited from the wider public to work over large and ecologically meaningful spatial scales. Optimizing working in partnership with unpaid, volunteer citizen scientists and conservationists requires an understanding of the determinants of volunteer retention rates and how they are affected by management practices. To this effect, we present the novel use of the mark‐recapture framework widely used in wildlife demography in order to quantify volunteer retention probabilities. We illustrate the versatility and power of the approach using a project that removed invasive American mink from 10,000 km2 in Scotland in partnership with volunteer citizen conservationists recruited from local communities. Wide scale adoption of the mark‐recapture framework to analyze volunteer management will give novel insights into how volunteers interact with the conservation projects they are involved in and provide evidence for their optimal management.
Why do Boards Differ? Because Owners Do: Assessing Ownership Impact on Board Composition
Authors: Sur Sujit , Lvina Elena , Magnan Michel 
Published: March 2013

AbstractManuscript TypeEmpiricalResearch Question/IssueDoes the ownership structure of a firm, specifically the aggregation of the different ownership types within each firm, relate with the composition of its board?Research Findings/InsightsUsing archival data from a sample comprising 1,487 U.S. firms, we find that the composition of the individual profiles of directors on corporate boards (i.e., independent, affiliated, or insider) match a firm's aggregated ownership configuration (institutional, corporate parent, family‐entrepreneur control) even after parsing out the impact of CEO characteristics, firm size, and performance. Further analyses elaborate on the specific relationship between each director profile and ownership types present within the firm.Theoretical/Academic ImplicationsThis study builds upon three conceptual perspectives: agency, resource dependency, and behavioral. We argue that each type of ownership has differing imperatives and may prefer different types of directors to fulfill their governance needs. The paper illustrates that the relationship between corporate governance, specifically board composition, and ownership is a comprehensive phenomenon that is best understood through multiple theoretical lenses.Practitioner/Policy ImplicationsThis study shows that ownership and board composition are not substitutable governance mechanisms as commonly understood, but might be complementary mechanisms. A finding that governance mechanisms are complementary implies that regulatory or institutional pressures to modify board composition with the addition of directors with similar profiles may affect the governance in unforeseen ways.
Basaloid tumors in nevus sebaceus revisited: the follicular stem cell marker PHLDA1 (TDAG51) indicates that most are basal cell carcinomas and not trichoblastomas
Authors: Sellheyer Klaus , Cribier Bernard , Nelson Paula , Kutzner Heinz , Rütten Arno 
Published: March 2013

BackgroundUntil the 1990s, basal cell carcinoma (BCC) was viewed as the most common epithelial neoplasm developing in association with nevus sebaceus (NS). Currently, trichoblastoma is thought of as the most prevalent basaloid neoplasm in NS. The follicular stem cell marker pleckstrin homology‐like domain, family A, member 1 (PHLDA1) also known as T‐cell death‐associated gene 51 (TDAG51) labels trichoepithelioma (TE) but not BCC. Therefore, we explored its usefulness in basaloid neoplasms developing in NS.MethodsWe studied immunohistochemically PHLDA1 in 10 nodular BCCs, 11 TEs, 11 trichoblastomas and 25 NS with basaloid tumors. Additionally, we examined the expression of BCC marker BerEP4 and the distribution of Merkel cells that function as surrogate markers for benign follicular neoplasms.ResultsNineteen of the 25 basaloid tumors in NS were PHLDA1‐negative comparable to BCC arising de novo and six tumors were PHLDA1‐positive comparable to solitary trichoblastomas and TEs. Fewer Merkel cells were seen in BCCs associated with NS when compared with trichoblastoma. BerEP4 did not discriminate between the neoplasms.ConclusionsWe raise concern that the unquestioned assessment that basaloid tumors developing in association with NS represent mostly trichoblastomas and not BCC may not be true. This influences clinical care, as it is paramount in the decision of whether to excise these lesions or not.
Regimes of Dispossession: From Steel Towns to Special Economic Zones
Authors: Levien Michael 
Published: March 2013

ABSTRACTThis article compares land dispossession for industrial development under state‐developmentalism and neoliberalism in India. Drawing on interviews, ethnography and archives of industrial development agencies, it compares earlier steel towns and state‐run industrial estates with today's Special Economic Zones (SEZs) and argues that they embody different regimes of dispossession. While steel towns and industrial estates reflected a regime of land for production with pretensions of inclusive social transformation, SEZs represent a neoliberal regime of land for the market in which ‘land broker states’ have emerged to indiscriminately transfer land from peasants to capitalist firms for real estate. The present regime has been unable to achieve the ideological legitimacy of its predecessor, leading to more widespread and successful ‘land wars’. The article argues more broadly that variations in dispossession across space and time can be understood as specific constellations of state roles, economic logics tied to class interests and ideological articulations of the ‘public good’.
Indirect Dispossession: Domestic Power Imbalances and Foreign Access to Land in Mozambique
Authors: Fairbairn Madeleine 
Published: March 2013

ABSTRACTRather than treating the global land grab as a top‐down phenomenon driven by global markets or foreign states, this article instead highlights the crucial mediating role played by the host state and domestic elites through a case study of Mozambique. I first introduce the domestic institutional framework, particularly the national Land Law and the institutions that determine the economic value of land. I then argue for an analysis of large‐scale land acquisitions that brings into focus the effects of domestic power imbalances on determining the outcomes of foreign demand for land. I examine the ways in which domestic inequality may shape foreign land acquisitions through a typology of the sources of power that give domestic elites a privileged role in relation to foreign investors. The five sources of domestic power considered are: traditional authority, bureaucratic influence, historical accumulation, locally‐based business knowledge and networks, and control over the development agenda. Finally, I conclude that the emphasis placed on the actions of the foreigner by both opponents (via framings of land acquisitions as neocolonialism or imperialism) and proponents (via solutions rooted in corporate codes of conduct) may obscure the ways in which pre‐existing domestic inequality conditions the outcomes of these deals.
Building the Politics Machine: Tools for ‘Resolving’ the Global Land Grab
Authors: Dwyer Michael B. 
Published: March 2013

ABSTRACTThe recent proliferation of transnational land deals has put the long‐fraught relationship between international cooperation, national development and local dispossession back in the political spotlight. This article argues that transnational land access cannot be resolved as a political question without a better understanding of the material, legal and administrative geographies that accompany and enable it. Using evidence from Laos, the paper illustrates two tools for ‘resolving’ the global land grab geographically: first, a biographical or trajectory‐based approach that connects specific land grabs to larger development landscapes (e.g. of urban infrastructuring); and second, genealogies of property formalization that interrogate and deconstruct the legal geographies of land access, both on and off the map. The paper concludes by suggesting that these tools have purchase elsewhere as well.
Chinese Land‐Based Interventions in Senegal
Authors: Buckley Lila 
Published: March 2013

ABSTRACTAs Chinese land‐based interventions multiply across the African continent, this article focuses on a single Chinese–Senegalese government‐run agriculture demonstration centre to provide insight into the daily realities of Chinese–African interactions on African land. Ethnographic methodologies are employed to examine practices and discourses on agricultural governance among Chinese and Senegalese informants. Building on theories of agriculture as performance, I show how distinct repertoires for land management are negotiated and reshaped by different subjects in a kind of improvised dance, where individuals’ improvisations lead to unanticipated project outcomes. What emerges is a picture of a Chinese agricultural management regime for African land that is simultaneously fraught with conflict, while also replete with collaboration benefiting some smallholder farmers. This actor‐oriented approach provides a critical empirical lens as well as a research framework for engaging more constructively with Chinese in large‐scale land acquisitions. I argue that ‘land grabbing’ must be seen not as a straightforward, linear process of state or corporate takeover of global land, but as a dynamic performance of negotiation among diverse state actors, corporate players and citizens — one that will reshape global development in unanticipated ways.
Road Mapping: Megaprojects and Land Grabs in the Northern Guatemalan Lowlands
Authors: Grandia Liza 
Published: March 2013

ABSTRACTFrom IIRSA (Integration of Regional Infrastructure in South America) to the PPP (Puebla to Panama Plan, later renamed the Mesoamerica Project), development banks are sponsoring a renewed wave of mega‐infrastructure projects across the Americas to support corporate trade and commerce. Concurrent with these are donor‐led efforts to modernize land administration systems, including a US$ 31 million World Bank loan (1998–2007) to survey and legalize settler claims in the northern Guatemalan department of Petén. Contrary to project planners’ stated goals of sustainable development, infrastructure projects have coincided with widespread land grabbing (up to 46 per cent of smallholder lands) by cattle ranchers, African palm plantations, narco traffickers, and other imbricated elites. Documenting the crossings and conjunctures of the PPP with market‐led agrarian reform, this ethnographic study suggests that the Guatemalan military may be a shadow beneficiary of new power assemblages emerging from the narco/cattle/agro‐industrial land concentration occurring in Petén.
Advantages of Real Time Three‐Dimensional Echocardiography in the Assessment of Right Ventricular Volumes and Function in Patients with Pulmonary Hypertension Compared with Conventional Two‐Dimensional Echocardiography
Authors: Di Bello Vitantonio , Conte Lorenzo , Delle Donne Maria Grazia , Giannini Cristina , Barletta Valentina , Fabiani Iacopo , Palagi Caterina , Nardi Carmela , Dini Frank Lloyd , Marconi Letizia , Paggiaro Pierluigi , Palla Antonio , Marzilli Mario 
Published: March 2013

BackgroundIn recent years, right ventricular (RV) function has acquired greater relevance as a clinical and prognostic marker in many physiopathological conditions. The study aims to point out the value of real time three‐dimensional echocardiography (RT3DE) and tissue Doppler imaging (TDI) in the evaluation of patients affected by pulmonary hypertension (PH), compared with conventional two‐dimensional (2D) echocardiography.MethodsWe enrolled 44 subjects affected by PH who underwent 2D and Doppler echocardiography, RT 3D Echocardiography and TDI evaluation of the RV, and a healthy control group. PH itself can induce severe functional and structural abnormalities of the RV, such as RV hypertrophy, RV dilation, and RV systolic and diastolic dysfunction.ResultsIn this study, RV FAC, and TAPSE showed marked alterations in patients with PH compared to the control group (C): (RVFAC: [PH] 0.29 ± 0.07 vs. [C] 0.49 ± 0.05%, P < 0.0001; TAPSE: [PH] 15.3 ± 3.2 vs. [C] 21.1 ± 2.6 mm, P > 0.0001). The 3D RV end‐diastolic volume was significantly higher in PH than in C (PH) (138.7 ± 25.3 vs. [C] 82.8 ± 12.5 mL, P < 0.0001] as well as 3D RV end‐systolic volume (PH) (97.6 ± 21.5 vs. [C] 39.3 ± 9.5 mL, P < 0.0001). The 3D RV ejection fraction (EF) was significantly lower in the pulmonary hypertension group than in healthy subjects (31.8 ± 6.8 vs. [C] 52.5 ± 4.7%, P < 0.0001).ConclusionsIn patients with PH, evaluation of the RV diastolic and systolic volume and EF by RT3DE has shown a higher discriminating power in comparison, respectively, with 2DRV diastolic area and the relative fractional area changes.