bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modified Ovate Pontic Design for Immediate Anterior Tooth Replacement
Authors: Mhatre Swapnali , Gala Anita 
Published: September 2012

ABSTRACTPontic is an artificial substitute for the missing tooth. The design of this prosthetic tooth will be dictated by esthetics, functions, hygiene, patient comfort and maintenance of the edentulous ridge. An ovate pontic has been widely recommended to fulfill both esthetic and functional requirements of the prosthesis. The convex design of this pontic intends to form a concave soft tissue outline at the site of the alveolar ridge mucosa. This design eliminates the ‘black triangle’ which is created after loss of tooth and interdental papilla. Clinically, healthy conditions can be established at pontic site, if appropriate plaque control is performed.Unfortunately, an ovate pontic design is not frequently advised by the clinicians. The case report presented a modified ovate pontic design for replacing upper anterior tooth to give both esthetics and health.How to cite this articleMhatre S, Gala A, Ram SM, Shah N. Modified Ovate Pontic Design for Immediate Anterior Tooth Replacement. J Contemp Dent 2012;2(2):64-68.
Polymorphisms upstream of the melanocortin‐1 receptor coding region are associated with human pigmentation variation in a Brazilian population
Authors: Neitzke‐Montinelli Vanessa , Urmenyi Turan P. , Rondinelli Edson , Cabello Pedro Hernan , Silva Rosane , Moura‐Neto Rodrigo S. 
Published: September 2012

AbstractObjective:We describe an association of two SNPs, rs3212345:C>T and rs3212346:G>A, located approximately 2.5 kb upstream of the melanocortin‐1 receptor (MC1R) translation initiation codon, with pigmentation phenotype variation in a Southeast Brazilian miscegenated population.Methods:One hundred thirty‐eight genetically unrelated subjects, with multicolor phenotype, were selected from the southeast region of Brazil. Skin, hair and eye color, and tanning ability were rated. Genotypes for each SNP (rs3212345:C>T and rs3212346:G>A) were determined. A logistic regression analysis was performed with the additive model to determine which of the polymorphisms contributed to a specific phenotype.Results:We found that the rs3212345:C>T is associated with light skin, red hair, and poor tanning ability, while the rs3212346:G>A is associated with dark skin, black hair, and strong tanning ability. The presence of rs3212345‐C and rs3212346‐A alleles in human, chimpanzee, gorilla, orangutan, and marmoset genomes suggests that they are the ancestral alleles.Conclusion:These data suggest that the rs3212345‐T and rs3212346‐G alleles may have contributed to lighter pigmentation phenotypes in modern humans. Genotyping for these SNPs may prove useful to the fields of molecular anthropology and forensic genetics. Am. J. Hum. Biol. 2012. © 2012 Wiley Periodicals, Inc.
Older farmers and machinery exposure—cause for concern?
Authors: Voaklander Don , Day Lesley , Dosman James , Hagel Louise , Pickett William 
Published: September 2012

AbstractBackgroundThe average age of farmers in North America is increasing each year. We had the unique opportunity to examine work patterns and how they change across the lifespan in a large cohort of farm operations.MethodsSaskatchewan farms were surveyed via questionnaire during the winter of 2007 to examine the determinants of injury. A sub‐sample of 2,751 male farmers aged 25 and older was used in this project. The primary dependent variable was the proportion of work time devoted to specific farm tasks which was related to advancing age.ResultsThe weekly hours of work declined approximately 34% as farmers aged over the lifespan. Older farmers disproportionately retained tasks involving tractors and combines as they aged, so that the proportion of time spent operating machinery such as tractors and combines increased by about 40% in the older age groups.ConclusionExposure to potentially dangerous farm equipment does not decrease as much as would be expected based on an equal linear reduction in all work tasks as overall work quantity decreases with age. Older farmers remain relatively active in the workplace, and, therefore, prevention efforts should focus on safe machinery operation. Am. J. Ind. Med. 55:1044–1050, 2012. © 2012 Wiley Periodicals, Inc.
Excess healthcare costs associated with prior workers' compensation activity
Authors: Bhattacharya Anasua , Park Robert M. 
Published: September 2012

AbstractBackgroundWorkers compensation (WC) does not fully compensate workplace injuries and illnesses. This work examines whether cost shifting occurs to group health insurance for work‐related injuries and illnesses.MethodsThomson Reuters MarketScan databases of medical insurance claims were used. WC and other benefit system data, employee status and types of medical insurance coverage were also available. Medical cost was analyzed using two‐part models: the first part modeled the monthly probability of a worker having any group health medical claims, and the second part modeled the total monthly cost of those medical claims. Models included an estimate of a worker's annual medical costs prior to a WC claim. The predicted monthly medical costs were derived by retransformation using Duan's smearing factor.ResultsIndividuals with prior WC claims were more likely to file a group health medical claim compared to those with no prior WC claims (OR = 1.25) and incurred a higher average monthly medical costs (among nonunion hourly men aged 18–34 years with prior WC claims: $203.72 vs. $160.29 with no prior claim, an increase of $43). These increases were observed in all industrial sectors with the service sector having the highest monthly increase ($66).DiscussionThe results reveal that individuals with prior WC claims had higher probability of filing a group health medical claim and higher average monthly medical costs in all sectors. This suggests that a part of employer liability costs related to WC gets shifted to the group health medical insurance system. Am. J. Ind. Med. 55:1018–1027, 2012. © 2012 Wiley Periodicals, Inc.
Occupational exposures and mortality from cardiovascular disease among women textile workers in Shanghai, China
Authors: Gallagher Lisa G. , Ray Roberta M. , Li Wenjin , Psaty Bruce M. , Gao Dao Li , Thomas David B. , Checkoway Harvey 
Published: September 2012

AbstractBackgroundExposure to textile fiber dusts, like particulate air pollution, may be associated with cardiovascular disease (CVD) mortality. Bacterial endotoxin, a potent inflammagen found in cotton dust, may be a specific risk factor.MethodsFemale textile workers (N = 267,400) in Shanghai, China were followed for CVD mortality (1989–2000). Factory exposures were approximated by sector classifications based on materials and processes. Quantitative endotoxin and cotton dust measures were available for a subcohort (n = 3,188). Cox proportional hazards modeling was used to estimate hazard ratios (HR) and 95% confidence interval (CI).ResultsSlightly elevated mortality risk for the cotton sector was seen for ischemic stroke (HR = 1.12, 95% CI: 0.97–1.31) and hemorrhagic stroke (HR = 1.12, 95% CI: 1.02–1.23). Similar hemorrhagic stroke mortality risk was observed in high dust sectors (HR = 1.12, 95% CI: 1.02–1.24). No association was observed for ischemic heart disease.ConclusionsExposures in textile factories may have contributed to CVD mortality among this cohort. The specific components of these exposures that may be harmful are not clear and should be further investigated. Am. J. Ind. Med. 55:991–999, 2012. © 2012 Wiley Periodicals, Inc.
Expanding the concepts and tools of metabolic engineering to elucidate cancer metabolism
Authors: Keibler Mark A. , Fendt Sarah‐Maria , Stephanopoulos Gregory 
Published: September 2012

AbstractThe metabolic engineer's toolbox, comprising stable isotope tracers, flux estimation and analysis, pathway identification, and pathway kinetics and regulation, among other techniques, has long been used to elucidate and quantify pathways primarily in the context of engineering microbes for producing small molecules of interest. Recently, these tools are increasingly finding use in cancer biology due to their unparalleled capacity for quantifying intracellular metabolism of mammalian cells. Here, we review basic concepts that are used to derive useful insights about the metabolism of tumor cells, along with a number of illustrative examples highlighting the fundamental contributions of these methods to elucidating cancer cell metabolism. This area presents unique opportunities for metabolic engineering to expand its portfolio of applications into the realm of cancer biology and help develop new cancer therapies based on a new class of metabolically derived targets. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
A Photochemical Mechanism for Homochirogenesis. Part 2
Authors: Bartmess John E. , Pagni Richard M. 
Published: September 2012

ABSTRACTA theoretical investigation of the photochemistry of racemic compounds with circularly polarized light was undertaken. The exact solutions of the differential equations by numerical integration to the approximate solutions used in an earlier article were compared. The exact solutions showed that sequential reactions yield enhanced optical activities in the products. For irreversible reactions, all enantiomeric excesses are lost if the reactions are carried to completion, but appreciable resolution occurs in many cases for partial conversion. For reversible reactions, significant enantiomeric excesses are found at the photostationary state. Chirality 25:16‐21, 2013. © 2012 Wiley Periodicals, Inc.
Lightweight Concrete with Tailor‐Made Expanded Aggregates
Authors: Rübner Katrin , Schnell Alexander , Haamkens Frank , Jakubcová Petra , Müller Anette 
Published: September 2012

AbstractNeue leichte Gesteinskörnungen werden durch rohstoffliches Recycling aus heterogenem und feinkörnigem Mauerwerkbruch hergestellt. Die Erprobung dieser Aufbaukörnungen im Leichtbeton liefert Aussagen zu ihrer Qualität und Eignung. Nach einer kurzen Charakterisierung der für die Betonherstellung ausgewählten Aufbaukörnungen werden die entworfene Betonrezeptur vorgestellt und einige Ergebnisse der Festbetonuntersuchungen diskutiert.
Analysis and design of a two‐transformer active‐clamping ZVS isolated inverse‐SEPIC converter
Authors: Lo Yu‐Kang , Lin Jing‐Yuan , Yen Shang‐Chin , Lin Liang‐Chun 
Published: September 2012

SUMMARYThis paper presents a two‐transformer active‐clamping zero‐voltage‐switching (ZVS) isolated inverse‐SEPIC converter, which is mainly composed of two active‐clamping ZVS isolated inverse‐SEPIC converters. The proposed converter allows a low‐profile design for liquid crystal display TVs and servers. The presented two‐transformer active‐clamping ZVS isolated inverse‐SEPIC converter can equally share the total load current between two secondaries. Therefore, the output inductor copper loss and the output diode conduction loss can be decreased. Detailed analysis and design of this new two‐transformer active‐clamping ZVS isolated inverse‐SEPIC converter are described. Experimental results are recorded for a prototype converter with an AC input voltage ranging from 85 to 135 V, an output voltage of 12 V and a rated output current of 13.5A, operating at a switching frequency of 65 kHz. Copyright © 2012 John Wiley & Sons, Ltd.
Generation of a germ cell‐specific mouse transgenic cherry reporter, Sohlh1‐mCherryFlag
Authors: Suzuki Hitomi , Dann Christina Tenenhaus , Rajkovic Aleksandar 
Published: September 2012

AbstractVisualization of differentiating germ cells is critical to understanding the formation of primordial follicles in the ovary, and the commitment of spermatogonial stem cells to differentiation. We engineered and generated a BAC transgenic mouse line, Sohlh1‐mCherryFlag (S1CF), under the direction of the native Sohlh1 promoter. Sohlh1 is a germ cell‐specific gene that encodes the basic helix‐loop‐helix (bHLH) transcriptional regulator that is essential in oogenesis and spermatogenesis. Sohlh1 expression is unique, and is limited to perinatal and early follicle oocytes and differentiating spermatogonia. The Sohlh1‐mCherryFlag transgene was engineered to fuse SOHLH1 to the red fluorescent protein CHERRY with 3‐tandem‐FLAG tags. S1CF animals fluoresce specifically in the oocytes of perinatal ovaries and small follicles in adult ovaries, as well as in spermatogonia, a pattern that is similar to endogenous SOHLH1. Moreover, S1CF rescued germ cell loss and infertility in both male and female Sohlh1−/− animals. The FLAG‐tag on S1CF was effective for immunostaining and immunoprecipitation. The Sohlh1‐mCherryFlag transgenic mouse provides a unique model to study early germ cell differentiation, as well as in vivo imaging and purification of differentiating germ cells. genesis 51:50–58, 2013. © 2012 Wiley Periodicals, Inc.
Male pheromone polymorphism and reproductive isolation in populations of Drosophila simulans
Authors: Bontonou Gwénaëlle , Denis Béatrice , Wicker‐Thomas Claude 
Published: September 2012

AbstractThe dominant cuticular hydrocarbons (HC) in Drosophila simulans are 7‐tricosene (7‐T) and 7‐pentacosene (7‐P). The 7‐T is the major HC in East Africa and in other continents. In West Africa, D. simulans is very rare and displays 7‐P as the major compound. We studied three D. simulans strains from Egypt (Eg), Sao‐Tome (ST), and Cameroon (Cam), with 7‐T, intermediary or 7‐P phenotypes. HC profiles of ST and Cam female differed slightly from corresponding male profiles; females had more 7‐T and less 7‐P. Varying temperature affected all HCs (even those with 27 and 29 carbons)‐not just 7‐T and 7‐P; there was no clear relationship between HC phenotype and resistance to desiccation. We report reproductive isolation between Eg and ST and Eg and Cam (but not between ST and Cam), which is due to Eg and Cam female preferences for their own males. In conclusion, our findings do support divergence of D. simulans populations from West Africa for both pheromonal profile and mating preference.
Growth and Chemical Stability of Copper Nanostructures on Cellulosic Fibers
Authors: Pinto Ricardo J. B. , Neves Márcia C. , Neto Carlos Pascoal , Trindade Tito 
Published: September 2012

AbstractThe design of paper products based on copper nanoparticles (NPs) is a challenge because of the intrinsic propensity of Cu to oxidize in contact with air. Here, a comparative study on the growth and chemical stability of Cu NPs in vegetable and bacterial cellulose is described for the first time. Furthermore, comparative studies were performed by using inorganic fillers of distinct dimensionality, Cu NPs and Cu nanowires (NWs), in both types of cellulose. Cu NWs were found to be more resistant to oxidation caused by prolonged air exposure than the Cu NPs. Notably, the cellulosic matrices behave differently for the growth or adsorption of the Cu nanofillers; bacterial cellulose fibers are the most efficient substrate to delay surface oxidation. The data support a role for bacterial cellulose in limiting the oxidation of Cu nanostructures that have been grown or blended in this type of matrix, hence opening up new perspectives for the development of electronic paper technologies that incorporate copper nanophases.
Water‐Soluble (Pterin)rhenium(I) Complex: Synthesis, Structural Characterization, and Two Reversible Protonation–Deprotonation Behavior in Aqueous Solutions
Authors: Ragone Fabricio , Ruiz Gustavo T. , Piro Oscar E. , Echeverría Gustavo A. , Cabrerizo Franco M. , Petroselli Gabriela , Erra‐Balsells Rosa , Hiraoka Kenzo , García Einschlag Fernando S. , Wolcan Ezequiel 
Published: September 2012

AbstractA new water‐soluble complex, Re(CO)3(pterin)(H2O), was synthesized and characterized by 1H NMR and FTIR spectroscopy, and by a combination of three mass spectrometry techniques: MALDI, probe electrospray ionisation (PESI), and ESI. Because, unlike most metal‐pterin complexes, the ReI complex is quite soluble in water, appropriate single crystals could be obtained for structural X‐ray analysis. We report here the first solid state molecular structure containing a pterin ligand coordinated to the Re(CO)3 core. This determination revealed that strong H bonds between the hydrogen atom of the 2‐amino group and crystallization water molecules give rise to a polymeric arrangement of Re(CO)3(pterin)(H2O) complexes in the lattice. Protonation studies in aqueous solutions of the ReI complex showed two acid‐base equilibriums with pKa1 = 3.9 and pKa2 = 8.8. pKa1 was assigned to the protonation equilibrium at N3 of the pterin ligand in the complex and pKa2 could be ascribed to the deprotonation of a coordinated water molecule.
The Use of a Nitroxide Probe in DMSO to Capture Free Radicals in Particulate Pollution
Authors: Stevanovic Svetlana , Miljevic Branka , Eaglesham Geoff K. , Bottle Steven E. , Ristovski Zoran D. , Fairfull‐Smith Kathryn E. 
Published: September 2012

AbstractA profluorescent nitroxide was used to evaluate the oxidative potential of pollution derived from a compression ignition engine fuelled with biodiesel. The reaction products responsible for the observed fluorescence increase when a DMSO solution of nitroxide was exposed to biodiesel exhaust were determined by using HPLC/MS. The main fluorescent species was identified as a methanesulfonamide adduct arising from the reaction of the nitroxide with DMSO‐derived sulfoxyl radicals.
Preparation of NH‐Pyrroles under Superelectrophilic Conditions by an Aza‐Nazarov Reaction Cascade with Indole as Neutral Leaving Group: Experiment and Theory
Authors: Narayan Rishikesh , Daniliuc Constantin‐Gabriel , Würthwein Ernst‐Ulrich 
Published: September 2012

AbstractAza‐Nazarov reactions starting from 1‐azapenta‐1,4‐dien‐3‐ones offer an attractive route to five‐membered nitrogen heterocycles such as N‐substituted pyrroles. It has now been discovered that N‐indolinylhydrazone‐derived 1‐azapenta‐1,4‐dien‐3‐one 9a gives different products under conditions of varying acidity. Under strongly acidic conditions (2 equiv. of triflic acid, dilute solution, “electrophilic” conditions) it simply undergoes an aza‐Nazarov reaction to give N‐indolinylpyrrole 15a after workup with acetic anhydride. If, however, a large excess of triflic acid is used (7–10 equiv., concentrated solution, “superelectrophilic” conditions), 9a has been found to undergo an aza‐Nazarov reaction cascade followed by N–N bond cleavage to give NH‐pyrrole 10a and acetylated indole 8 as the final products (after workup with acetic anhydride). High‐level quantum chemical calculations were used to explain this acid‐concentration‐dependent reaction cascade. The formation of the reaction products can be explained in terms of an electrocyclization reaction of the protonated starting material 9a and a subsequent N–N bond cleavage reaction involving either mono‐ or dicationic species under strongly acidic conditions.
Water Flow in, Through, and Around the Gas Diffusion Layer
Authors: Gauthier E. , Duan Q. , Hellstern T. , Benziger J. 
Published: September 2012

AbstractLiquid water produced in polymer electrolyte membrane fuel cells is transported from the cathode catalyst/membrane interface through the gas diffusion layer (GDL) to the gas flow channel. Liquid water travels both laterally (in the plane of GDL) and transversely through the largest pores of the porous GDL structure. Narrow apertures in the largest pores are the primary resistance to liquid water penetration. Carbon paper has limiting apertures ∼20 μm in diameter and ∼1 μm in length whereas carbon cloth has apertures ∼100 μm in diameter and ∼200 μm in length. After sufficient hydrostatic pressure is applied, water penetrates the limiting aperture and flows through the pore. The pressure required for water to flow through the pores is less than the pressure to penetrate the limiting aperture of the pores. Water moved laterally and directed through a small number of transverse pores. There is less resistance to lateral liquid water flow at the interface between the GDL and a solid surface than through the GDL. The results from these experiments suggest that water flow through the GDL is dominated by a small number of pores and most pores remain free of liquid water.
Estradiol‐induced increase in novel object recognition requires hippocampal NR2B‐containing NMDA receptors
Authors: Vedder Lindsey C. , Smith Caroline C. , Flannigan Alaina E. , McMahon Lori L. 
Published: September 2012

Abstract17β‐estradiol (E2), at high circulating levels, enhances learning and memory in many women, making it a clinical treatment for hormone‐related cognitive decline in aging. However, the mechanisms stimulated by E2, which are responsible for its cognitive enhancing effects, remain incompletely defined. Using an ovariectomized rat model, we previously reported that increasing plasma E2 enhances the magnitude of long‐term potentiation (LTP) at hippocampal CA3‐CA1 synapses, which is caused by a selective increase in current mediated by NR2B‐containing NMDARs, leading to an increase in the NMDAR/AMPAR ratio. Whether the increase in NR2B current is causally related to the ability of E2 to enhance hippocampal dependent learning and memory has yet to be tested. Here, we find that E2 enhances performance in the novel object recognition (NOR) task with the same time course we previously showed E2 enhances the LTP magnitude, temporally linking the increase in LTP to enhanced learning and memory. Furthermore, using the selective NR2B subunit antagonist Ro25‐6981, we find that the E2‐enhanced NOR, like the enhanced LTP, requires hippocampal NR2B‐containing NMDARs, specifically in area CA1. Finally, using whole‐cell recordings and the phosphatase inhibitor orthovanadate, we investigated whether the E2‐induced increase in NMDAR current is caused by an increase in the density of synaptic NMDARs and/or an increase in NMDAR subunit phosphorylation. We find that both mechanisms are responsible for the enhanced NMDAR current in E2‐treated rats. Our results show that the E2‐enhanced NOR requires a functional increase in NR2B‐containing NMDARs, a requirement shared with the E2‐enhanced LTP magnitude at CA3‐CA1 synapses, supporting the hypothesis that the increase in LTP likely contributes to the enhanced learning and memory following an increase in plasma E2 levels. © 2012 Wiley Periodicals, Inc.