bluuebunny/crossref_metadata_2025 huggingface dataset:
Conflicting Family Values in Mutual Fund Families
Authors: BHATTACHARYA UTPAL , LEE JUNG H. , POOL VERONIKA K.
Published: December 2012

We analyze the investment behavior of affiliated funds of mutual funds (AFoMFs), which are mutual funds that can only invest in other funds in the family, and are offered by most large families. Though never mentioned in any prospectus, we discover that AFoMFs provide an insurance pool against temporary liquidity shocks to other funds in the family. We show that, though the family benefits because funds can avoid fire sales, the cost of this insurance is borne by the investors in the AFoMFs. The paper thus uncovers some of the hidden complexities of fiduciary responsibility in mutual fund families.
Irritable Bowel Syndrome in Women
Authors: Roisinblit Katie Caulfield
Published: December 2012

Irritable bowel syndrome is a gastrointestinal disorder characterized by abdominal pain and changes in bowel habits. It adversely affects the quality of life for women who have it and is a significant health care burden. The syndrome results from the interaction of many factors that are not clearly understood, including stress, environment (internal and external), and biological mechanisms. It affects women more than men, and clear biological, psychological, and physical differences exist between the sexes, creating the need for a specialized approach to management in women. The objective of this article is to explore the pathophysiology of irritable bowel syndrome and how it relates specifically to women and to apply these differences to the diagnosis and treatment of irritable bowel syndrome in women.
Simultaneous Estimation of Cost and Distance Function Share Equations
Authors: Clark J. Stephen , Cechura Lukas , Thibodeau David R.
Published: December 2012

The study considers the simultaneous estimation of share equations using cost and distance functions. Simultaneous rather than single system estimation utilizes full as opposed to limited information. Econometric results exploit the nonstationary nature of the data and that variables are cointegrated. Under cointegration all variables are endogenous and so it is not necessary to undertake the somewhat ad hoc exercise of choosing instruments to achieve parameter consistency. Johansen's maximum likelihood estimator is applied to data from Central Canada and Western Canada (1935–2006). Symmetry and homogeneity restrictions are not rejected for either region. Monotonicity held for all data points and concavity held at 92% of the data points. Long‐run constant returns and Hicks neutral technological change are rejected for both regions. Morishima elasticity estimates coming from the cost function in Western Canada indicate highly elastic long‐run substitution between the land/fertilizer input pair and mildly elastic long‐run substitution between land and both machinery and labor. In contrast, substitution for land and other inputs is inelastic for the land/machinery pair and the land/labor pair, with only the land/fertilizer pair being mildly elastic. The results indicate the limiting nature of land as a fundamental constraint on long‐term agricultural production is a real possibility in Central Canada because other inputs are inelastic, or at best only mildly elastic, substitutes for land. In Western Canada, fertilizer is the only factor that is highly substitutable for land and, therefore, could mitigate the limiting nature of land in that region. However, given that fertilizer applications are often considered to be environmentally unfriendly, the long‐run substitution of fertilizer for land as a fundamental mitigating factor to land scarcity in Western Canada is at a cost to the environment.
Cost‐Effective Control Strategies for Johne's Disease in Dairy Herds
Authors: Cho Jaesung , Tauer Loren W. , Schukken Ynte H. , Smith Rebecca L. , Lu Zhao , Grohn Yrjo T.
Published: December 2012

Johne's disease (JD), or paratuberculosis, is an incurable and infectious disease of ruminants, caused by infection with Mycobacterium avium ssp. paratuberculosis (MAP), and costing an estimated CAD$15 million in Canada and US$200–$250 million in the United States. This study examines the economic and epidemiological consequences of various MAP control options in the context of controlling JD in dairy herds. A discrete optimal control model is developed utilizing the disease‐specific animal compartment model and maximizing the net present value of a dairy operation. The results identify the optimal control option together with the associated herd dynamics and optimal culling rates of cows in different infection states. The results show that comprehensive, effective, and profitable JD control programs can be developed for dairy farms.
The Pallant v Morgan equity reconsidered
Authors: Yip Man
Published: December 2012

This paper argues that the Pallant v Morgan equity should not be recognised as an independent doctrine because it does not rest on any tenable jurisprudential basis. It shows that a characterisation based on ‘common intention’ should be rejected because it is inconsistent with established legal principles and commercial practice. The alternative explanation based on breach of fiduciary duty, as suggested by Etherton LJ in Crossco No. 4 Unlimited v Jolan Unlimited [2011] 2 All ER 754 fares no better, as there is no reason why the Pallant v Morgan equity cases should be considered separately from other instances of breach of fiduciary duty in law. Further, this account must however be read in light of the Court of Appeal's decision in Sinclair Investments (UK) Ltd v Versailles Trade Finance Ltd [2011] 3 WLR 1153 which ruled that proprietary relief is only allowed in circumstances where the breach amounts to abuse of the principal's asset. This requirement is particularly difficult to satisfy in the paradigm case of the Pallant v Morgan equity, save in the case of agency. But where there is a relationship of agency, a constructive trust will also arise in accordance with an established agency principle, resulting in duplication in results.
Clifford Geertz’s Interpretive Approach to Religion
Authors: Segal Robert A.
Published: December 2012

Clifford Geertz is often lauded as the key social scientist in the contemporary shift from an interpretive approach to religion and to culture in general to an explanatory approach. Supposedly, the shift is from concern with the cause of religion to concern with the meaning of religion. This article argues, first, that Geertz associates an interpretive approach with an array of distinct considerations and argues, second, that Geertz actually seeks to combine an interpretive approach with an explanatory one rather than to substitute an interpretive approach for an explanatory one.
Late Neolithic expansion of ancient Chinese revealed by Y chromosome haplogroup O3a1c‐002611
Authors: WANG Chuan‐Chao , YAN Shi , QIN Zhen‐Dong , LU Yan , DING Qi‐Liang , WEI Lan‐Hai , LI Shi‐Lin , YANG Ya‐Jun , JIN Li , LI Hui ,   the Genographic Consortium
Published: December 2012

Y chromosome haplogroup O3‐M122 is the most prevalent haplogroup in East Asia, and provides an ideal tool for dissecting primary dispersals of the East Asians. Most of the sub‐haplogroups of O3‐M122 have been sufficiently investigated except for O3a1c‐002611, despite its great prevalence and huge population, especially in Han Chinese. In this study, we identified 508 individuals with haplogroup O3a1c‐002611 out of 7801 males from 117 East and Southeast Asian populations, typed at two newly discovered downstream Y‐SNP markers and ten commonly used Y‐STRs. Defined by SNPs IMS‐JST002611 (in short, 002611), F11, and F238, three lineages internal to haplogroup O3a1c‐002611 have distinct geographical distributions. Furthermore, Y‐STR diversity shows a general south‐to‐north decline, which is consistent with the prehistorically northward migration of the other O3‐M122 lineages. The northward migration of haplogroup O3a1c‐002611 started about 13 thousand years ago (KYA). The expansions of subclades F11 and F238 in ancient Han Chinese began about 5 and 7 KYA immediately after the separation between the ancestors of the Han Chinese and Tibeto‐Burman.
Propagation of impact‐induced shock waves in porous sandstone using mesoscale modeling
Authors: GÜLDEMEISTER Nicole , WÜNNEMANN Kai , DURR Nathanael , HIERMAIER Stefan
Published: December 2012

Abstract–

Generation and propagation of shock waves by meteorite impact is significantly affected by material properties such as porosity, water content, and strength. The objective of this work was to quantify processes related to the shock‐induced compaction of pore space by numerical modeling, and compare the results with data obtained in the framework of the Multidisciplinary Experimental and Modeling Impact Research Network (MEMIN) impact experiments. We use mesoscale models resolving the collapse of individual pores to validate macroscopic (homogenized) approaches describing the bulk behavior of porous and water‐saturated materials in large‐scale models of crater formation, and to quantify localized shock amplification as a result of pore space crushing. We carried out a suite of numerical models of planar shock wave propagation through a well‐defined area (the “sample”) of porous and/or water‐saturated material. The porous sample is either represented by a homogeneous unit where porosity is treated as a state variable (macroscale model) and water content by an equation of state for mixed material (ANEOS) or by a defined number of individually resolved pores (mesoscale model). We varied porosity and water content and measured thermodynamic parameters such as shock wave velocity and particle velocity on meso‐ and macroscales in separate simulations. The mesoscale models provide additional data on the heterogeneous distribution of peak shock pressures as a consequence of the complex superposition of reflecting rarefaction waves and shock waves originating from the crushing of pores. We quantify the bulk effect of porosity, the reduction in shock pressure, in terms of Hugoniot data as a function of porosity, water content, and strength of a quartzite matrix. We find a good agreement between meso‐, macroscale models and Hugoniot data from shock experiments. We also propose a combination of a porosity compaction model (ε–α model) that was previously only used for porous materials and the ANEOS for water‐saturated quartzite (all pore space is filled with water) to describe the behavior of partially water‐saturated material during shock compression. Localized amplification of shock pressures results from pore collapse and can reach as much as four times the average shock pressure in the porous sample. This may explain the often observed localized high shock pressure phases next to more or less unshocked grains in impactites and meteorites.
Deformation of dry and wet sandstone targets during hypervelocity impact experiments, as revealed from the MEMIN Program
Authors: BUHL Elmar , POELCHAU Michael H. , DRESEN Georg , KENKMANN Thomas
Published: December 2012

Abstract– Hypervelocity impact experiments on dry and water‐saturated targets of fine‐grained quartz sandstone, performed within the MEMIN project, have been investigated to determine the effects of porosity and pore space saturation on deformation mechanisms in the crater’s subsurface. A dry sandstone cube and a 90% water‐saturated sandstone cube (Seeberger Sandstein, 20 cm side length, about 23% porosity) were impacted at the Fraunhofer EMI acceleration facilities by 2.5 mm diameter steel spheres at 4.8 and 5.3 km s−1, respectively. Microstructural postimpact analyses of the bisected craters revealed differences in the subsurface deformation for the dry and the wet target experiments. Enhanced grain comminution and compaction in the dry experiment and a wider extent of localized deformation in the saturated experiment suggest a direct influence of pore water on deformation mechanisms. We suggest that the pore water reduces the shock impedance mismatch between grains and pore space, and thus reduces the peak stresses at grain–grain contacts. This effect inhibits profound grain comminution and effective compaction, but allows for reduced shock wave attenuation and a more effective transport of energy into the target. The reduced shock wave attenuation is supposed to be responsible for the enhanced crater growth and the development of “near surface” fractures in the wet target.
Deep differentiation between and within Mediterranean glacial refugia in a flying mammal, the Myotis nattereri bat complex
Authors: Salicini Irene , Ibáñez Carlos , Juste Javier
Published: December 2012

Aim

The role of glacial refugia in the biogeographical patterns in the Western Palaearctic region has been widely discussed, but many questions remain unresolved. We examined the biogeography, genetic diversity, spatial distribution and evolutionary history of the Myotis nattereri bat species complex to investigate the presence of multiple refugia and the persistence of Quaternary differentiation between and within Mediterranean refugia in a flying mammal.

Location

Western Palaearctic region (central and southern Europe and north‐western Maghreb).

Methods

We analysed three mitochondrial fragments (cytochrome b, NADH dehydrogenase subunit 1 and the control region; 1570 bp) from 136 individuals of the M. nattereri complex sampled from 87 different localities using a range of phylogenetic techniques. Divergences among clades were also dated using a Bayesian coalescence approach.

Results

Phylogenetic analyses identified four main lineages, coincident with the four cryptic species recently described. Each species is further subdivided into well‐supported lineages with evident geographical structure. Estimates of genetic diversity and polymorphism were very high for the majority of subclades, with the exception of M. nattereri s.s.

Main conclusions

The M. nattereri bat complex comprises four species whose distributions in the Western Palaearctic correspond to four main glacial refugia (Iberia, Italy, Balkans and Morocco). These species are the result of long‐term isolation (remarkable in a flying mammal) over several glacial cycles. The Balkan species expanded into central Europe in a rapid recolonization process. Both the Iberian and Italian peninsulas show a clear pattern of refugia‐within‐refugia in their genetic structuring, with a deeply differentiated southern Italian clade. Morocco shows two markedly differentiated lineages, probably separated by the Atlas Mountains. The legacy of Pleistocene cycles is evident in both the speciation and the intraspecific diversification events.
Palynology supports ‘OldNorse’ introductions to the flora ofGreenland
Authors: Schofield J. Edward , Edwards Kevin J. , Erlendsson Egill , Ledger Paul M.
Published: December 2012

Aim

This paper integrates pollen‐analytical data from sites across southernGreenland to revisit the debate regarding which plants may have been introduced during theNorse colonization orlandnám c. ad985.

Location

Palynological data are drawn from 14 sites (lakes and mires) located within the formerEasternSettlement ofNorseGreenland (c. 60.9° N, 45.5° W).

Methods

Maps are presented displaying palynological data for three taxa (Rumex acetosella,Polygonum aviculareandAchillea millefolium), which earlier scholars have argued are ‘Old Norse’ anthropochores. The maps display pollen frequencies at regular (c. 100‐year) intervals across a period (ad800–1500) encompassingNorse settlement.

Results

Maps forc. ad800 and 900 (prior toNorse arrival) display the taxa as locally absent, with the appearance and expansion of their pollen at multiple sites fromc. ad1000 (landnám) providing support for the assumption that each taxon arrived with the first settlers. A general and widespread decline in pollen frequencies for these ‘Old Norse’ elements on thec. ad1500 map (followingNorse abandonment) demonstrates a close connection between these plants and a cultural landscape that was shaped and maintained predominantly via animal husbandry.

Main conclusions

Patterns emerging from this exercise may initiate wider debates related to the pattern and character of theNorse colonization ofGreenland. It is suggested that differences in the function or role of farm sites could have led to the creation of greater areas of favourable habitat for ‘OldNorse’ flora in some locations relative to others, and that uneven patterns of colonization and the spread of ‘OldNorse’ plants might be explained if their introduction – presumably from Iceland – first occurred at only a few locations.
Small businesses and flood impacts: the case of the 2009 flood event in Cockermouth
Authors: Wedawatta G. , Ingirige B. , Proverbs D.
Published: December 2012

Flooding can have a devastating impact on businesses, especially on small‐ and medium‐sized enterprises (SMEs) who may be unprepared and vulnerable to the range of both direct and indirect impacts. SMEs may tend to focus on the direct tangible impacts of flooding, limiting their ability to realise the true costs of flooding. Greater understanding of the impacts of flooding is likely to contribute towards increased uptake of flood protection measures by SMEs, particularly during post‐flood property reinstatement. This study sought to investigate the full range of impacts experienced by SMEs located in Cockermouth following the floods of 2009. The findings of a questionnaire survey of SMEs revealed that businesses not directly affected by the flooding experienced a range of impacts and that short‐term impacts were given a higher significance. A strong correlation was observed between direct, physical flood impacts and post‐flood costs of insurance. Significant increases in the costs of property insurance and excesses were noted, meaning that SMEs will be exposed to increased losses in the event of a future flood event. The findings from the research will enable policy makers and professional bodies to make informed decisions to improve the status of advice given to SMEs. The study also adds weight to the case for SMEs to consider investing in property‐level flood risk adaptation measures, especially during the post flood reinstatement process.
Flood vulnerability of the Karun River System and short‐term mitigation measures
Authors: Heidari A.
Published: December 2012

Karun River Basin in south‐west of Iran has accommodated a large number of hydro projects including reservoirs, hydropower plants, water convey systems, and irrigation networks. Recent extreme floods of the basin have resulted in damage to the vulnerable flood plain areas and under‐construction dam sites. Structural and non‐structural approach was pursued to reduce the vulnerability of the region after extreme floods of 2005 and 2006. The paper describes the historical floods and the solutions that were recently implemented in the basin. Resistant cofferdams along with early flood forecasting system (EFFS) and emergency action plan (EAP) have been identified as adoptive short‐term solutions. The EFFS incorporates a regional numerical weather forecast system, rainfall–run‐off models, a reservoir flood control simulation model, flood routing, and two‐dimensional inundation models. Depending on the location of the sites, maximum lead time of forecast is 4–5 days, which is sufficient to evacuate the area and damage centres. An EAP was made for dam break and extreme flood events including maps of hazardous zones and access maps to safe areas in the damage centres, mainly in the large cities of the flood plain area.
Colorectal endoscopic submucosal dissection: Is it suitable in western countries?
Authors: Uraoka Toshio , Parra‐Blanco Adolfo , Yahagi Naohisa
Published: December 2012

Endoscopic submucosal dissection (ESD) represents a significant advance in therapeutic endoscopy with the major advantage being the ability to achieve a higher en bloc resection rate for early stage lesions. Western endoscopists infrequently perform colorectal ESD (CR‐ESD) because of the greater technical difficulty involved, longer procedure times, and increased risk of perforation. Specialized training and sufficient clinical experience are necessary to successfully perform ESDs, but a systematic education and training program has still not been established in Japan or elsewhere in the world. Experts generally acknowledge that the stomach is the first organ in which endoscopists should begin performing ESDs. The incidence and detection rates for early stage gastric cancer are significantly higher in Japan than in western countries, so Japanese endoscopists have a greater opportunity to perform gastric ESDs than their western counterparts. It is logical to ask, therefore, whether CR‐ESD can be effectively applied in western countries. Based on a review of the relevant literature and our practical perspective, we have focused on the progress made in performing CR‐ESD, its indications, training methods, and learning curve. Use of animal gastric and colon models is strongly recommended along with accumulating the necessary experience from the rectum to the colon on a step‐by‐step basis. It is reasonable to assume that an increasing number of CR‐ESDs will be performed by western endoscopists in the foreseeable future given the continuing development of new techniques, and the refinement of instruments and other technologically advanced devices together with the creation of even more effective submucosal injection agents.
Prevalence of adenomas and sessile serrated adenomas in Chinese compared with Caucasians
Authors: Kumbhari Vivek , Behary Jason , Hui Jason Minco
Published: December 2012

Background and Aims

Colonic adenomas and sessile serrated adenomas (SSA) are the most common premalignant polyps identified at colonoscopy. This study compares the prevalence of neoplastic polyps in Chinese and Caucasians in a general gastroenterology outpatient practice in Australia.

Methods

This study included consecutive unselected colonoscopies performed for standard clinical indications by a single endoscopist (JMH). All polyps detected were measured, resected, and sent for histopathology. The prevalence of adenomas, advanced adenomas, SSA, and cancer in the Chinese and Caucasian cohorts were compared. Advanced adenomas were defined as adenomas > 10 mm, villous histology, or high‐grade dysplasia.

Results

The study included 346 Chinese and 654 Caucasians. There was no significant difference in the baseline characteristics including age, gender, and indications of colonoscopy, although Chinese were more likely to present with rectal bleeding (22.8% vs 15.9%, P = 0.01). The prevalence of adenomatous polyps was similar in both Caucasians (34.3%) and Chinese (35.3%). However, advanced adenomas were more significantly common in Caucasians (11.3%) compared with Chinese (4.6%) (P < 0.001). SSA was rare in Chinese (2%) but present more frequently in Caucasians (7%) (P = 0.001). Multivariate analysis showed that Caucasian ethnicity (odds ratio 2.4, 95% confidence interval 1.6–3.6) and the presence of SSA (odds ratio 4.4, 95% confidence interval 2.3–8.6) were independent predictors for the detection of an advanced adenoma.

Conclusions

The prevalence of significant colorectal lesions, including advanced adenomas, large adenomas, and SSA, were lower in Chinese compared with Caucasians. These findings may influence the guidelines for colonic cancer screening in Chinese populations.
Impact of leptin receptor gene variants on risk of non‐alcoholic fatty liver disease and its interaction with adiponutrin gene
Authors: Zain Shamsul Mohd , Mohamed Zahurin , Mahadeva Sanjiv , Cheah Phaik‐Leng , Rampal Sanjay , Chin Kin‐Fah , Mahfudz Anis Shafina , Basu Roma Choudhury , Tan Hwa‐Li , Mohamed Rosmawati
Published: December 2012

Background and Aim

Genetic polymorphism has been implicated as a factor for the occurrence of non‐alcoholic fatty liver disease (NAFLD). This study attempted to assess whether polymorphisms in the leptin receptor (LEPR) gene and its combined effect with patatin‐like phospholipase domain‐containing protein 3 (PNPLA3/adiponutrin) are associated with risk of NAFLD.

Methods

A total of 144 biopsy‐proven NAFLD and 198 controls were genotyped using the Sequenom MassARRAY platform.

Results

We observed a significant association between the LEPR rs1137100 and rs1137101 with susceptibility to NAFLD (odds ratio [OR] 1.64, 95% confidence interval [CI] 1.18–2.28, P = 0.003; and OR 1.61, 95% CI 1.11–2.34, P = 0.013, respectively) and to non‐alcoholic steatohepatitis (OR 1.49, 95% CI 1.05–2.12, P = 0.026; and OR 1.57, 95% CI 1.05–2.35, P = 0.029, respectively). The LEPR rs1137100 is also associated with simple steatosis (OR 2.27, 95% CI 1.27–4.08, P = 0.006). Analysis of gene–gene interaction revealed a strong interaction between the LEPR and PNPLA3 genes (empirical P = 0.001). The joint effect of LEPR and PNPLA3 greatly exacerbated the risk of NAFLD (OR 3.73, 95% CI 1.84–7.55, P < 0.0001). The G allele of rs1137100 is associated with lower fibrosis score (OR 0.47, 95% CI 0.28–0.78, P = 0.001).

Conclusions

We report an association between variants of LEPR rs1137100 and rs1137101 with risk of NAFLD. This study suggests that rs1137100, specifically the G allele, is associated with a less severe form of liver disease in patients with NAFLD. The interaction between LEPR and PNPLA3 genes showed increased risk of NAFLD compared to either gene alone.
Controlled trial of ligation plus vasoconstrictor versus proton pump inhibitor in the control of acute esophageal variceal bleeding
Authors: Lo Gin‐Ho , Perng Daw‐Shyong , Chang Chi‐Yang , Tai Chi‐Ming , Wang Huay‐Min , Lin Hui‐Chen
Published: December 2012

Background

Endoscopic therapy combined with vasoconstrictor was generally recommended to treat acute variceal bleeding. However, up to 30% of patients may still encounter treatment failure.

Objectives

This trial was to evaluate the efficacy of combination with endoscopic variceal ligation (EVL) and proton pump inhibitor (PPI) infusion in patients with acute variceal bleeding.

Methods

Cirrhotic patients presenting with acute esophageal variceal bleeding were rescued by emergency EVL. Soon after arresting of bleeding varices, eligible subjects were randomized to two groups. Vasoconstrictor group received either somatostatin or terlipressin infusion. PPI group received either omeprazole or pantoprazole. End points were initial hemostasis, very early rebleeding rate, and adverse events.

Results

Sixty patients were enrolled in vasoconstrictor group and 58 patients in PPI group. Both groups were comparable in baseline data. Initial hemostasis was achieved in 98% in vasoconstrictor group and 100% in PPI group (P = 1.0). Very early rebleeding within 48–120 h occurred in one patient (2%) in vasoconstrictor group and one patient (2%) in the PPI group (P = 1.0). Treatment failure was 4% in vasoconstrictor group and 2% in PPI group (P = 0.95). Adverse events occurred in 33 patients (55%) in vasoconstrictor group and three patients (6%) in PPI group (P < 0.001). Two patients in vasoconstrictor group and one patient in PPI group encountered esophageal ulcer bleeding.

Conclusions

After successful control of acute variceal bleeding by EVL, adjuvant therapy with PPI infusion was similar to combination with vasoconstrictor infusion in terms of initial hemostasis, very early rebleeding rate, and associated with fewer adverse events.
Financial Knowledge and Child Development Account Policy: A Test of Financial Capability
Authors: HUANG JIN , NAM YUNJU , SHERRADEN MARGARET S.
Published: December 2012

This study examines how study participants' financial knowledge and participation in a Child Development Account intervention affects 529 College Savings Plan account holding among caregivers of infants. The study uses data from the SEED for Oklahoma Kids (N = 2,651), a statewide randomized experiment using a probability sample of infants selected from birth records. Results of logit regression show that participants' financial knowledge is positively related to account holding in the treatment group but not in the control group. The interactive effects between financial knowledge and treatment status are statistically significant. This finding implies that the effect of financial knowledge on financial decisions related to college savings is moderated by institutional features, such as incentives, information and access. Results of this study support the propositions of financial capability and suggest that expanding financial capability requires both improved individual financial knowledge and supportive policy.
CD1a‐positive Langerhans cells and their relationship with E‐cadherin in ameloblastomas and keratocystic odontogenic tumors
Authors: Mello Leonardo Araújo , Figueiredo Andréia Leal , Ramos Eduardo Antônio Gonçalves , Gurgel Clarissa Araújo Silva , Martins Manoela Domingues , de Figueiredo Claúdia Roberta Leite Vieira , Cury Patrícia Ramos , de Albuquerque Júnior Ricardo Luiz Cavalcanti , Ramalho Luciana Maria Pedreira , Santos Jean Nunes dos
Published: December 2012

Background

Ameloblastomas and keratocystic odontogenic tumors (KOTs) are lesions that are characterized by locally invasive growth and cause extensive bone destruction. In addition, it is known that E‐cadherin influences the adhesion of Langerhans cells (LCs) to keratinocytes.

Objective and Methods

The aim of this study was to investigate, using immunohistochemistry, the distribution of CD1a‐positive cells in ameloblastomas and KOTs and their relationship with E‐cadherin, in comparison to calcifying cystic odontogenic tumor (CCOT).

Results

The CD1a‐positive LCs were observed in 11 ameloblastomas and KOTs. All of the cases of CCOT showed CD1a‐positive LCs and a significant difference was found when this tumor was compared with ameloblastomas (P < 0.05, Mann–Whitney test). A statistically significant difference was also noted when comparing CD1a‐positive LCs between CCOTs and KOTs (P < 0.05, Mann–Whitney test). Lower expression of E‐cadherin in ameloblastomas (AMs) in relation to KOTs and CCOTs (P < 0.05, Fisher test) was observed. There was no correlation between E‐cadherin and CD1a‐positive LCs between all odontogenic tumors that were studied (P > 0.05, Spearman test).

Conclusion

A quantitative difference of CD1a‐positive cells between AMs and KOTs in comparison to CCOTs was observed. This permits to speculate that a depletion of CD1a‐positive LCs might influence the local invasiveness of ameloblastomas and KOTs. Furthermore, it is suggested that E‐cadherin mediates cell adhesion in these tumors.
Melatonin inhibits matrix metalloproteinase‐9 activity by binding to its active site
Authors: Rudra Deep Sankar , Pal Uttam , Maiti Nakul Chandra , Reiter Russel J. , Swarnakar Snehasikta
Published: December 2012

The zinc‐dependent matrix metalloproteinases (MMPs) are key enzymes associated with extracellular matrix (ECM) remodeling; they play critical roles under both physiological and pathological conditions. MMP‐9 activity is linked to many pathological processes, including rheumatoid arthritis, atherosclerosis, gastric ulcer, tumor growth, and cancer metastasis. Specific inhibition of MMP‐9 activity may be a promising target for therapy for diseases characterized by dysregulated ECM turnover. Potent MMP‐9 inhibitors including an indole scaffold were recently reported in an X‐ray crystallographic study. Herein, we addressed whether melatonin, a secretory product of pineal gland, has an inhibitory effect on MMP‐9 function. Gelatin zymographic analysis showed a significant reduction in pro‐ and active MMP‐9 activity in vitro in a dose‐ and time‐dependent manner. In addition, a human gastric adenocarcinoma cell line (AGS) exhibited a reduced (~50%) MMP‐9 expression when incubated with melatonin, supporting an inhibitory effect of melatonin on MMP‐9. Atomic‐level interaction between melatonin and MMP‐9 was probed with computational chemistry tools. Melatonin docked into the active site cleft of MMP‐9 and interacted with key catalytic site residues including the three histidines that form the coordination complex with the catalytic zinc as well as proline 421 and alanine 191. We hypothesize that under physiological conditions, tight binding of melatonin in the active site might be involved in reducing the catalytic activity of MMP‐9. This finding could provide a novel approach to physical docking of biomolecules to the catalytic site of MMPs, which inhibits this protease, to arrest MMP‐9‐mediated inflammatory signals.
Exogenous melatonin improves Malus resistance to Marssonina apple blotch
Authors: Yin Lihua , Wang Ping , Li Mingjun , Ke Xiwang , Li Cuiying , Liang Dong , Wu Shan , Ma Xinli , Li Chao , Zou Yangjun , Ma Fengwang
Published: December 2012

We examined whether exogenously applied melatonin could improve resistance to Marssonina apple blotch (Diplocarpon mali) by apple [Malus prunifolia (Willd.) Borkh. cv. Donghongguo]. This serious disease leads to premature defoliation in the main regions of apple production. When plants were pretreated with melatonin, resistance was increased in the leaves. We investigated the potential roles for melatonin in modulating levels of hydrogen peroxide (H2O2), as well the activities of antioxidant enzymes and pathogenesis‐related proteins during these plant–pathogen interactions. Pretreatment enabled plants to maintain intracellular H2O2 concentrations at steady‐state levels and enhance the activities of plant defence‐related enzymes, possibly improving disease resistance. Because melatonin is safe and beneficial to animals and humans, exogenous pretreatment might represent a promising cultivation strategy to protect plants against this pathogen infection.
Mechanisms shaping plant biomass and species richness: plant strategies and litter effect in alkali and loess grasslands
Authors: Kelemen András , Török Péter , Valkó Orsolya , Miglécz Tamás , Tóthmérész Béla
Published: December 2012

Question

Explaining the biomass–species richness relationship is key to understanding vegetation dynamics. Several possible mechanisms have been suggested, but complex analysis of plant strategies, major biomass and species richness components along a long productivity gradient is still lacking. We provide a detailed analysis of the relationship between major biomass components (total above‐ground biomass, green biomass and litter), plant strategies and species richness along a long gradient of alkali and loess grasslands in a steppe landscape in Central Europe.

Location

Hortobágy, Great Hungarian Plain, East Hungary.

Methods

Above‐ground biomass of characteristic alkali and loess grassland stands was sampled along a gradient of increasing productivity. In each grassland stand, a 25‐m2 sample site was randomly selected. Within each site, ten above‐ground biomass samples (20 × 20 cm) were collected randomly in June 2009, at the peak of biomass production. We classified all species into mixed C‐S‐R strategy types. To obtain correlations between various biomass and species richness data, Spearman rank correlation was used. The relationship between plant strategies and species composition were displayed with a DCA ordination.

Results

The frequently detected humped‐back relationship was valid for the relation of total biomass and species richness. With increasing amount of total biomass, we detected an increasing proportion of competitors, and a decreasing proportion of stress tolerators in green biomass. A low proportion of ruderals was detected at both low and high biomass levels. Species richness was affected positively by litter at low litter scores, but there was a negative litter effect from much lower scores than detected previously (from 400 g·m−2). There was a positive relationship between green biomass production and species richness.

Conclusions

The study revealed that at the initial part of a productivity gradient, stress is likely responsible for low species richness. Our results show that litter can shape changes in species richness along the whole biomass gradient, thus the litter effect is one of the major mechanisms structuring grassland diversity.
The first MEMIN shock recovery experiments at low shock pressure (5–12.5 GPa) with dry, porous sandstone
Authors: KOWITZ Astrid , SCHMITT Ralf T. , UWE REIMOLD W. , HORNEMANN Ulrich
Published: December 2012

Abstract– As part of the MEMIN research program this project is focused on shock deformation experimentally generated in dry, porous Seeberger sandstone in the low shock pressure range from 5 to 12.5 GPa. Special attention is paid to the influence of porosity on progressive shock metamorphism. Shock recovery experiments were carried out with a high‐explosive set‐up that generates a planar shock wave, and using the shock impedance method. Cylinders of sandstone of average grain size of 0.17 mm and porosity of about 19 vol%, and containing some 96 wt% SiO2, were shock deformed. Shock effects induced with increasing shock pressure include: (1) Already at 5 GPa the entire pore space is closed; quartz grains show undulatory extinction. On average, 134 fractures per mm are observed. Dark vesicular melt (glass) of the composition of the montmorillonitic phyllosilicate component of this sandstone occurs at an average amount of 1.6 vol%. (2) At 7.5 GPa, quartz grains show weak but prominent mosaicism and the number of fractures increases to 171 per millimeter. Two additional kinds of melt, both based on phyllosilicate precursor, could be observed: a light colored, vesicular melt and a melt containing large iron particles. The total amount of melt (all types) increased in this experiment to 2.4 vol%. Raman spectroscopy confirmed the presence of shock‐deformed quartz grains near the surface. (3) At 10 and 12.5 GPa, quartz grains also show weak but prominent mosaicism, the number of fractures per mm has reached a plateau value of approximately 200, and the total amount of the different melt types has increased to 4.8 vol%. Diaplectic quartz glass could be observed locally near the impacted surface. In addition, local shock effects, most likely caused by multiple shock wave reflections at sandstone‐container interfaces, occur throughout the sample cylinders and include locally enhanced formation of PDF, as well as shear zones associated with cataclastic microbreccia, diaplectic quartz glass, and SiO2 melt. Overall findings from these first experiments have demonstrated that characteristic shock effects diagnostic for the confirmation of impact structures and suitable for shock pressure calibration are rare. So far, they are restricted to the limited formation of PDF and diaplectic quartz glass at shock pressures of 10 GPa and above.
Recalculation of data for short‐lived radionuclide systems using less‐biased ratio estimation
Authors: TELUS M. , HUSS G. R. , OGLIORE R. C. , NAGASHIMA K. , TACHIBANA S.
Published: December 2012

Abstract–

Ratios determined from counting a subset of atoms in a sample are positively biased relative to the true ratio in the sample (Ogliore et al. 2011). The relative magnitude of the bias is approximately equal to the inverse of the counts in the denominator of the ratio. SIMS studies of short‐lived radionuclides are particularly subject to the problem of ratio bias because the abundance of the daughter element is low, resulting in low count rates. In this paper, we discuss how ratio bias propagates through mass‐fractionation corrections into an isochron diagram, thereby affecting the inferred initial ratio of short‐lived radionuclides. The slope of the biased isochron can be either too high or too low, depending on how it is calculated. We then reanalyze a variety of previously published data sets and discuss the extent to which they were affected by ratio bias. New, more accurate, results are presented for each study. In some cases, such as for 53Mn‐53Cr in pallasite olivines and 60Fe‐60Ni in chondrite sulfides, the apparent excesses of radiogenic isotopes originally reported disappear completely. Many of the reported initial 60Fe/56Fe ratios for chondrules from ordinary chondrites are no longer resolved from zero, though not all of them. Data for 10Be‐10B in CAIs were only slightly affected by bias because of how they were reduced. Most of the data sets were recalculated using the ratio of the total counts, which increases the number of counts in the denominator isotope and reduces the bias. However, if the sum of counts is too low, the ratio may still be biased and a less‐biased estimator, such as Beale’s estimator, must be used. Ratio bias must be considered in designing the measurement protocol and reducing the data. One can still collect data in cycles to permit editing of the data and to monitor and correct for changes in ion‐beam intensity, even if total counts are used to calculate the final ratio. The cycle data also provide a more robust estimate of the uncertainties from temporal variations in the secondary ion signal.
Spatial and temporal patterns of abundance of Aedes aegypti L. (Stegomyia aegypti) and Aedes albopictus (Skuse) [Stegomyia albopictus (Skuse)] in southern Florida
Authors: REISKIND M. H. , LOUNIBOS L. P.
Published: December 2012

Invasion by mosquito vectors of disease may impact the distribution of resident mosquitoes, resulting in novel patterns of vectors and concomitant risk for disease. One example of such an impact is the invasion by Aedes albopictus (Skuse) [Stegomyia albopictus (Skuse)] (Diptera: Culicidae) of North America and this species' interaction with Aedes aegypti L. (Stegomyia aegypti L). We hypothesized that Ae. aegypti would be found in urban, coastal areas that experience hotter and drier conditions, whereas Ae. albopictus would be more commonly found in suburban and rural areas that are cooler and wetter. In addition, we hypothesized that Ae. aegypti would be more abundant early in the wet season, whereas Ae. albopictus would be more abundant later in the wet season. Urban areas were drier, hotter and contained more Ae. aegypti than suburban or rural areas. Aedes aegypti was relatively more abundant early in the wet season, whereas Ae. albopictus was more abundant in both the late wet season and the dry season. The spatial patterns of inter‐ and intraspecific encounters between these species were also described. The distribution of these mosquitoes is correlated with abiotic conditions, and with temperature, humidity and the relative availability of rain‐filled containers. Understanding the ecological determinants of species distribution can provide insight into the biology of these vectors and important information for their appropriate control.
Permission to Believe: Why Permissivism Is True and What It Tells Us About Irrelevant Influences on Belief
Authors: Schoenfield Miriam
Published: December 2012

In this paper, I begin by defending permissivism: the claim that, sometimes, there is more than one way to rationally respond to a given body of evidence. Then I argue that, if we accept permissivism, certain worries that arise as a result of learning that our beliefs were caused by the communities we grew up in, the schools we went to, or other irrelevant influences dissipate. The basic strategy is as follows: First, I try to pinpoint what makes irrelevant influences worrying and I come up with two candidate principles. I then argue that one principle should be rejected because it is inconsistent with permissivism. The principle we should accept implies that it is sometimes rational to maintain our beliefs, even upon learning that they were caused by irrelevant influences.
Impurism, Practical Reasoning, and the Threshold Problem
Authors: Brown Jessica
Published: December 2012

I consider but reject one broad strategy for answering the threshold problem for fallibilist accounts of knowledge, namely what fixes the degree of probability required for one to know? According to the impurist strategy to be considered, the required degree of probability is fixed by one's practical reasoning situation. I distinguish two different ways to implement the suggested impurist strategy. According to the Relevance Approach, the threshold for a subject to know a proposition at a time is determined by the practical reasoning situations she is then in to which that particular proposition is relevant. According to the Unity Approach, the threshold for a subject to know any proposition whatsoever at a time is determined by a privileged practical reasoning situation she then faces, most plausibly the highest stakes practical reasoning situation she is then in. I argue that neither way of implementing the impurist strategy succeeds and so impurism does not offer a satisfactory response to the threshold problem.
Adaptation at range margins: common garden trials and the performance ofArabidopsis lyrataacross its northwestern European range
Authors: Vergeer Philippine , Kunin William E.
Published: December 2012

Widely distributed species, such as the perennial plantArabidopsis lyrata, face a range of environmental conditions across space, creating selective pressures for local evolutionary adaptation. The species' fragmented distribution may reduce gene flow, which could either reduce or increase adaptive potential. The substantial variation in phenotypic traits observed across this species' northwestern European range may reflect a combination of plastic responses to environmental conditions, evolutionary adaptation and nonadaptive genetic differentiation.

We conducted multi‐site common garden experiments to study differences in plant performance in core and marginal areas. Plants from eight source populations representing the species' full geographic and altitudinal range in northwestern Europe were planted out in Iceland, Sweden, Scotland and Wales.

We found evidence of both strong plastic responses and apparently adaptive differentiation in performance. Most evidence for local adaptation was found at range margins, with the strongest effects on reproductive output. Both biotic and abiotic factors affected performance, especially at range margins. Performance of most plants was best in the Scottish and Swedish common garden sites, in the core of the species' distribution.

Despite adaptations at range margins, the performance of the species declines at distributional limits, with extreme southern populations looking particularly vulnerable.
Antiepileptic drugs (AEDs) during pregnancy and risk of congenital jaw and oral malformation
Authors: Koo J , Zavras A
Published: December 2012

In the United States, an estimate of 1.3 million women suffering from epilepsy are in their childbearing age. Potential teratogenicity of antiepileptic drugs (AEDs) is of concern to these women considering pregnancy because discontinuing pharmacotherapy during pregnancy may not be advised due to the risk of seizures that may be dangerous to the mother as well as the fetus. Using a Relational Online Analytical Processing (ROLAP) software licensed by Simultek, we searched for medications reported for congenital jaw and oral cavity malformation on the FDA Adverse Event Reporting System (AERS), a voluntary adverse event reporting program that contains over 55 million adverse event reports of medical products in the United.States. Our results indicate that various forms of valproic acid, and more importantly, newer generation antiepileptic agents including lamotrigine, topiramate, and gabapentin show signals for either congenital jaw or oral malformation. Although teratogenic potential of valproic acid has long been confirmed, information on teratogenicity of the newer generation antiepileptic drugs is relatively scarce and inconclusive. Early safety signals on the teratogenic potential of AEDs detected in this study are crude statistics that do not establish causation nor exclude confounding. The results require validation and further investigation via properly controlled epidemiological studies.