bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dental arch asymmetry
Authors: Al-Zubair Nabil Muhsen 
Published: April 2014

ABSTRACT
Objective: This study was conducted to assess the dental arch asymmetry in a Yemeni sample aged (18-25) years. Materials and Methods: The investigation involved clinical examination of 1479 adults; only 253 (129 females, 124 males) out of the total sample were selected to fulfill the criteria for the study sample. Study models were constructed and evaluated to measure mandibular arch dimensions. Three linear distances were utilized on each side on the dental arch: Incisal-canine distance, canine-molar distance and incisal-molar distance, which represent the dental arch segmental measurements. Results: When applying “t-test” at P < 0.05, no significant differences were found between the right and left canine-molar, incisal-canine and incisal-molar distances in both dental arches for both sexes. The greater variation (0.30 mm) was observed between right and left canine-molar distance in the maxillary dental arch in male and the smaller (0.04 mm) in the mandibular dental arch between the right and left canine-molar distance in females. Conclusion: The findings of the present study revealed a symmetrical pattern of dental arches, since the right and left sides showed no statistically significant difference. In general, it can be observed that the measurements related to the central incisors and canines have the widest range of reading and give the impression that the location of central incisor and canines to each other and to other teeth is the strongest factor in determining the dental arch asymmetry.
Evaluation of formocresol, calcium hydroxide, ferric sulfate, and MTA primary molar pulpotomies
Authors: Yildiz Esma , Tosun Gul 
Published: April 2014

ABSTRACT
Objective: The aim of this study is to evaluate four different pulpotomy medicaments in primary molars. Materials and Methods: A total of 147 primary molars with deep caries were treated with four different pulpotomy medicaments (FC: formocresol, FS: ferric sulfate, CH: calcium hydroxide, and MTA: mineral trioxide aggregate) in this study. The criteria for tooth selection for inclusion were no clinical and radiographic evidence of pulp pathology. During 30 months of follow-up at 6-month intervals, clinical and radiographic success and failures were recorded. The differences between the groups were statistically analyzed using the Chi-square test and Kaplan-Meier analysis. Results: At 30 months, clinical success rates were 100%, 95.2%, 96.4%, and 85% in the FC, FS, MTA, and CH groups, respectively. In radiographic analysis, the MTA group had the highest (96.4%), and the CH group had the lowest success rate (85%). There were no clinical and radiographic differences between materials (P > 0.05). Conclusions: Although there were no differences between materials, only in the CH group did three teeth require extraction due to further clinical symptoms of radiographic failures during the 30-month follow-up period. None of the failed teeth in the other groups required extraction during the 30-month follow-up period.
Wear of two pit and fissure sealants in contact with primary teeth
Authors: Galo Rodrigo , Contente Marta Maria Martins Giamatei , Borsatto Maria Cristina 
Published: April 2014

ABSTRACT
Objectives: Wear simulations may provide an indication of the clinical performance of pit-and-fissure sealants when associated with primary teeth as counterbody, restricting the involved variables. The aim of this study was to evaluate wear of dental materials used as pit-and-fissure sealants in contact with primary teeth. Materials and Methods: A resinous sealant (Fluroshield®) and a resin-modified glass ionomer cement (Vitremer®) were selected in a post-plate design, using as counterbody primary tooth pins (4 × 4 × 2 mm) at 3 and 10 N vertical load, 1 Hz frequency, 900 wear cycles in artificial saliva (n = 15). Attrition coefficient values were obtained and the material and primary tooth volumes were analyzed. Data were analyzed statistically by ANOVA and Duncan's test (P < 0.05). Results: Fluroshield® presented the highest attrition coefficient values for the 3 N but these values decreased significantly for the 10 N load. The means for volume loss (3 mm) of the different samples after the wear test were not statistically different for the materials. The volume loss values for the primary teeth were statistically different and there was an increase in volume loss with the increase of the load applied in the wear tests. Conclusions: Differences were also observed with regard to the surface deformation characteristics. The wear rates of primary tooth enamel vary according to the type of material and the load applied during mastication.
On the ferrule effect and the biomechanical stability of teeth restored with cores, posts, and crowns
Authors: Mamoun John S. 
Published: April 2014

ABSTRACTAn abutment for a fixed partial denture may not contain enough tooth structure, such that the abutment does not provide an adequate ‘ferrule effect’. A crown or bridge dental prosthesis that is cemented onto such an abutment/s may undergo biomechanical failure. Here, the tooth, core, and post complex, on which the crown is cemented, may fracture off from the abutment, causing the crown to separate from the abutment, while the cement that bonds the crown to the tooth, core, and post complex remains intact, such that the tooth, core, and post complex remains inside the crown when the crown separates from the abutment. This article reviews the dentistry literature on the ferrule effect, and presents alternative definitions for terms such as ferrule, the ferrule effect, and the ferrule tooth structure. The article also explains how the use of a surgical operating microscope, or high magnification binocular surgical loupes of ×6-8, or greater magnification improve the ability of a dentist to assess how much ferrule tooth structure an abutment contains, compared to the use of unaided vision.
Gingival pigmentation index proposal of a new index with a brief review of current indices
Authors: Peeran Syed Wali , Ramalingam Karthikeyan , Peeran Syed Ali , Altaher Omar Basheer , Alsaid Fatma Mojtaba , Mugrabi Marei Hamed 
Published: April 2014

ABSTRACTCosmetic expectations have increased with time and current trends speak volumes about gingival esthetics and smile designing. Gingival pigmentation especially on the labial aspect of anterior teeth has become an important component of general esthetics. Various physiologic and pathologic factors cause gingival pigmentation. The existing indices do not deal with the etiology, extent and severity of gingival pigmentation. Hence, we propose a new classification and index for gingival pigmentation to assess the treatment needs for the patient.
Reliability and Validity of Conversion Formulas Between Comprehensive Osteopathic Medical Licensing Examination of the United States Level 1 and United States Medical Licensing Examination Step 1
Authors: Lee Albert S. , Chang Lynn , Feng Eric , Helf Scott 
Published: April 2014

Abstract

Background
The Comprehensive Osteopathic Medical Licensing Examination of the United States (COMLEX-USA) Level 1 and United States Medical Licensing Examination (USMLE) Step 1 scores are important factors in the selection process of medical students into US residency programs.

Objectives
The goals of this study were to investigate the correlation between the COMLEX-USA Level 1 and the USMLE Step 1 and to assess the accuracy of the existing formulas in predicting USMLE scores from COMLEX-USA scores.

Methods
A retrospective study of 1016 paired COMLEX-USA Level 1 and USMLE Step 1 scores was conducted. Formulas by Sarko et al and by Slocum and Louder were used to estimate USMLE Step 1 scores from COMLEX-USA Level 1 scores, and a paired t test between calculated USMLE Step 1 scores and actual USMLE Step 1 scores was performed.

Results
During 2006–2012, 1016 of 1440 students (71%) took both the USMLE Step 1 and the COMLEX-USA Level 1 tests in the College of Osteopathic Medicine of the Pacific. The USMLE Step 1 scores were higher than those predicted by Slocum and Louder and by Sarko et al by an average of 14.16 ± 11.69 (P &lt; .001) and 7.80 ± 12.48 (P &lt; .001), respectively. A Pearson coefficient of 0.83 was observed. Regression analysis yielded the following formula: USMLE Step 1  =  0.2392 × COMLEX-USA Level 1 + 82.563 (R2  =  0.69577).

Conclusions
The USMLE Step 1 scores, on average, were higher than those predicted by the formulas derived by Slocum and Louder and by Sarko et al. Residency program directors should use caution when using formulas to derive USMLE Step 1 scores from COMLEX-USA Level 1 scores.
L’innovation dans les services publics : gouvernance plutôt que gestion des risques
Authors: Osborne Stephen P. , Brown Louise 
Published: April 2014

Cet article étudie l’importante question des risques engendrés par les processus d’innovation dans les services publics. On y propose l’idée que les politiques publiques actuelles offrent peu d’orientation aux gestionnaires de services sur la façon de prendre en compte de tels risques, se résumant à mentionner que « c’est important ». Lorsqu’elles existent, les approches de prise en charge des risques et de l’innovation dans les services publics sont invariablement focalisées sur des optiques actuarielles ou concernées par les questions de santé et de sécurité, et ont pour objectif de minimiser ou d’éliminer les risques. Or les risques sont inhérents aux processus d’innovation et il est essentiel d’adopter une nouvelle approche qui reconnaît la nécessité des risques dans les innovations efficaces et qui s’engage de manière plus globale avec les intervenants afin de déterminer les niveaux de risque acceptables comparativement aux bienfaits potentiels pour les services publics d’une innovation donnée. Un modèle en cinq étapes est proposé pour mettre en oeuvre cette approche.
Cluster observations of hot He+ events in the inner magnetosphere
Authors: Yamauchi M. , Dandouras I. , Rème H. , Nilsson H. 
Published: April 2014

AbstractIn the inner magnetosphere inside 65° invariant latitude, Cluster Ion Spectrometry detected hot He+ events of about a few tens to several hundred eV without the same types of hot H+ signature at the same energy. During the 2001–2006 period when the Cluster orbit was almost constant and approximately north‐south symmetric at constant local time near the perigee, we found nearly 20 examples in Cluster spacecraft 4. These hot He+ events are morphologically classified into two burst types and two dispersed types: (1) Short intensification of He+ (1a) without corresponding H+ or O+ signatures, or (1b) with H+ signature at different pitch angles. (2) Energy‐latitude dispersed He+ stripes that continues for tens of minutes at hundreds to a few thousand eV range (2a) at different drift shell from energy‐latitude dispersed H+ stripes, or (2b) with very weak H+ signature if the energy is constant. While type‐1a is observed during or right after substorm activities, type‐2b is found after long quiet periods, i.e., after long drift. The relationship with the geomagnetic activity indicates that the plasmasphere can be energized in a mass‐dependent way in the evening sector during substorms to form the bursty types (type‐1), while the selective He+ energization can also take place during quiet periods near the noon. On the other hand, the source of the two dispersed types (type‐2) must be remote from the observation point, and the location and the geomagnetic conditions at the time of the He+ filtering is an open question.
Petrology‐based modeling of mantle melt electrical conductivity and joint interpretation of electromagnetic and seismic results
Authors: Pommier A. , Garnero E. J. 
Published: April 2014

AbstractThe presence of melt in the Earth's interior depends on the thermal state, bulk chemistry, and dynamics. Therefore, the investigation of the physical and chemical properties of melt is a probe of the planet's structure, dynamics, and potentially evolution. Here we explore melt properties by interpreting geophysical data sets sensitive to the presence of melt (electromagnetic and seismic) with considerations of petrology and, in particular, peridotite partial melting. We present a petrology‐based model of the electrical conductivity of fertile and depleted peridotites during partial melting. Seismic and magnetotelluric (MT) studies do not necessarily agree on melt fraction estimates, a possible explanation being the assumptions made about melt chemistry as part of MT data interpretation. Melt fraction estimates from electrical anomalies usually assume a basaltic melt phase, whereas petrological knowledge suggests that the first liquids produced have a different chemistry, and thus a different conductivity. Our results show that melts produced by low‐degree peridotite melting (< 15 vol %) are up to 5 times more conductive than basaltic liquids. Such conductive melts significantly affect bulk rock conductivity. Application of our electrical model to magnetotelluric results suggests melt fractions that are in good agreement with seismic estimates. With the aim of a simultaneous interpretation of electrical and seismic data, we combine our electrical results with seismic velocity considerations in a joint model of partial melting. Field electrical and seismic anomalies can be explained by ~1 vol % melt beneath Hawaii and ~1–8 vol % melt beneath the Afar Ridge.
On the distribution of CO2 and CO in the mesosphere and lower thermosphere
Authors: Garcia Rolando R. , López‐Puertas Manuel , Funke Bernd , Marsh Daniel R. , Kinnison Douglas E. , Smith Anne K. , González‐Galindo Francisco 
Published: April 2014

AbstractWe have used the Whole Atmosphere Community Climate Model (WACCM) to calculate the distribution of CO2 and CO in the mesosphere and lower thermosphere (MLT), and we have compared the results with observations, mainly from the Atmospheric Chemistry Experiment Fourier Transform Spectrometer and Michelson Interferometer for Passive Atmospheric Sounding satellite‐borne instruments. We find that WACCM can reproduce the observed distribution of CO2 in the MLT and the rapid falloff of CO2 above about 80 km. Analysis of the principal terms in the calculated budget of CO2 shows that its global‐mean vertical profile is determined mainly by the competition between molecular diffusive separation and eddy mixing by gravity waves. The model underestimates somewhat the mixing ratio of CO2 in the thermosphere compared to that in the observations, but we show that the discrepancy may be eliminated by a reasonable adjustment of the Prandtl number used to calculate the diffusivity due to gravity waves. Simulated CO is also consistent with observations, except that in the standard version of the model, its mixing ratio is uniformly lower than observed above about 100 km. We conclude that WACCM likely underestimates the rate of production of CO in the lower thermosphere from photolysis of CO2 at wavelengths < 121 nm, and we show that this stems from the use of a very large absorption cross section for O2 in the wavelength range 105–121 nm. When a smaller cross section is used, photolysis of CO2 increases by a factor of 2–3 at ~ 95–115 km and, as a result, CO mixing ratios become larger and agree much more closely with observations. We emphasize that the increase in CO2 photolysis implies only minor changes in the vertical profile of CO2 because photolytic loss is a minor term in the budget of CO2 in the MLT.
Effects of crop residue burning on aerosol properties, plume characteristics, and long‐range transport over northern India
Authors: Kaskaoutis D. G. , Kumar S. , Sharma D. , Singh R. P. , Kharol S. K. , Sharma M. , Singh A. K. , Singh S. , Singh Atinderpal , Singh D. 
Published: April 2014

AbstractAerosol emissions from biomass burning are of specific interest over the globe due to their strong radiative impacts and climate implications. The present study examines the impact of paddy crop residue burning over northern India during the postmonsoon (October–November) season of 2012 on modification of aerosol properties, as well as the long‐range transport of smoke plumes, altitude characteristics, and affected areas via the synergy of ground‐based measurements and satellite observations. During this period, Moderate Resolution Imaging Spectroradiometer (MODIS) images show a thick smoke/hazy aerosol layer below 2–2.5 km in the atmosphere covering nearly the whole Indo‐Gangetic Plains (IGP). The air mass trajectories originating from the biomass‐burning source region over Punjab at 500 m reveal a potential aerosol transport pathway along the Ganges valley from west to east, resulting in a strong aerosol optical depth (AOD) gradient. Sometimes, depending upon the wind direction and meteorological conditions, the plumes also influence central India, the Arabian Sea, and the Bay of Bengal, thus contributing to Asian pollution outflow. The increased number of fire counts (Terra and Aqua MODIS data) is associated with severe aerosol‐laden atmospheres (AOD500 nm > 1.0) over six IGP locations, high values of Ångström exponent (>1.2), high particulate mass 2.5 (PM2.5) concentrations (>100–150 µgm−3), and enhanced Ozone Monitoring Instrument Aerosol Index gradient (~2.5) and NO2 concentrations (~6 × 1015 mol/cm2), indicating the dominance of smoke aerosols from agricultural crop residue burning. The aerosol size distribution is shifted toward the fine‐mode fraction, also exhibiting an increase in the radius of fine aerosols due to coagulation processes in a highly turbid environment. The spectral variation of the single‐scattering albedo reveals enhanced dominance of moderately absorbing aerosols, while the aerosol properties, modification, and mixing atmospheric processes differentiate along the IGP sites depending on the distance from the aerosol source, urban influence, and local characteristics.
Low‐altitude summer/winter microphysics, dynamics, and CCN spectra of northeastern Caribbean small cumuli, and comparisons with stratus
Authors: Hudson James G. , Noble Stephen 
Published: April 2014

AbstractLow‐altitude cloud microphysics and cloud condensation nuclei (CCN) spectra are presented and analyzed from two cumulus cloud aircraft field campaigns, Ice in Clouds Experiment‐Tropical (ICE‐T) and Rain in Cumulus over the Ocean (RICO), in the same eastern Caribbean location at opposite seasons. These are further compared with two previously analyzed stratus cloud aircraft campaigns off the central California coast, Physics of Stratocumulus Tops (POST) and Marine Stratus/Stratocumulus Experiment (MASE). Multiple regression analysis predictions of cloud droplet concentrations (Nc) based on CCN spectra, NCCN(S) where S is supersaturation, compared much better with measured Nc than single NCCN‐Nc regressions in both cumulus projects. The addition of vertical velocity (W) to the single and multiple regressions showed small improvements. For RICO the multiple regression correlations were also superior to previous adiabatic model predictions of Nc also based on NCCN(S) and mean W. More adiabatic cloud parcels with considerably higher Nc, liquid water contents, and W showed only slightly better correlations than flight‐averaged Nc of all low clouds. Results show the value of more extensive CCN spectra and the relative unimportance of W variations for determining Nc, in these Caribbean cumuli. The fact that flight‐averaged Nc of all low cloud data was almost as well correlated with NCCN(S) as were Nc of more adiabatic cloud parcels indicates that entrainment did not significantly perturb CCN‐Nc relationships. As should be expected higher cloud S were determined for the cumulus clouds than for the stratus clouds. Suppression of cloud S by higher NCCN that had previously been observed in stratus was observed in ICE‐T but not in RICO where the NCCN range may have been too low for cloud S suppression. But ICE‐T and POST even showed this S suppression over the same limited NCCN range as RICO (< 200 cm−3).
On the possible interaction between internal climate variability and forced climate change
Authors: Lu Jianhua , Hu Aixue , Zeng Zhen 
Published: April 2014

AbstractThe global warming hiatus does not necessarily mean a hiatus in anthropogenic greenhouse gas forcing and forced climate change (FCC). Here we show that both Atlantic Multidecadal Variability (AMV) and Pacific Decadal Oscillation (PDO) may cause fluctuations of the global mean surface air temperature (SAT) and hence alternately positive and negative trends on (inter)decadal time scales. However, the forced SAT change under a mean state due to greenhouse gas forcing does not depend on different phases of AMV and PDO, implying the effect of the FCC and internally generated climate variability can be linearly added up to the observed transient global mean SAT. On the other hand, the regional patterns of transient FCC do depend on the phases of the internal variability since the atmospheric and oceanic circulations can be affected by the different phases of the internal variability. Our results suggest a two‐way interaction between internal variability and spatial patterns of FCC.
Assessing the Validity of the LOP in the EU Broiler Markets
Authors: Emmanouilides Christos J. , Fousekis Panos 
Published: April 2014

ABSTRACTThe objective of this article is to assess the validity of the Law of One Price (LOP) in five major EU broiler markets. This has been pursued using weekly price data from 1991 to 2012 and recent developments in econometric methodology that account simultaneously for nonstationarity, nonlinearity, and structural breaks. The empirical results provide strong evidence that the LOP holds, predominantly in its weak version. This implies that shocks are fully transmitted from one spatial market to the others, but price differences among them are likely to persist even in the long‐run.
Nasopharyngeal squamous cell carcinoma: a comparative analysis of keratinizing and nonkeratinizing subtypes
Authors: Vazquez Alejandro , Khan Mohemmed N. , Govindaraj Satish , Baredes Soly , Eloy Jean Anderson 
Published: April 2014

BackgroundNasopharyngeal squamous cell carcinoma (NPSCC) is uncommon in non‐endemic regions. Two major histologic subtypes are recognized: keratinizing (K‐NPSCC) and nonkeratinizing (NK‐NPSCC). We hypothesize that significant differences exist between the 2 in terms of demographic, clinicopathologic, survival, and prognostic features. We aim to show that differentiating between the 2 subtypes is perhaps the most important first step at the time of diagnosis.MethodsUsing a retrospective cohort design, the U.S. National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) registry was used to extract data on the 2 major subtypes of NPSCC. Frequency, incidence, and relative survival (RS) were analyzed comparatively. Regression analysis was conducted and hazard ratios (HRs) calculated.ResultsA total of 1624 cases were identified: 1234 (76.0%) cases of NK‐NPSCC and 390 (24.0%) cases of K‐NPSCC. Five‐year RS was 60.6% for NK‐NPSCC and 40.5% for K‐NPSCC. Regression analysis revealed K‐NPSCC to be a poor prognostic factor (HR 2.1; 95% confidence interval, 1.8–2.6; p < 0.0001). Other factors associated with a poor prognosis included female gender in K‐NPSCC, age greater than 44 years in both groups, and advanced‐stage disease at diagnosis. Favorable prognostic factors included Asian/Pacific Islander race, and treatment with radiation therapy. Higher histologic grade did not portend a worse prognosis for either group.ConclusionNPSCC remains an uncommon malignancy in the United States. K‐NPSCC and NK‐NPSCC represent 2 different histologic entities with important clinical differences. K‐NPSCC carries a worse overall prognosis when compared to NK‐NPSCC.