bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationships between epipelic diatoms, aquatic macrophytes, and water quality in Akarçay Stream, Afyonkarahisar, Turkey
Authors: Kargıoğlu Mustafa , Serteser Ahmet , Kıvrak Ersin , İçağa Yılmaz , Konuk Muhsin 
Published: December 2011

Abstract
The Akarçay is the most important stream in the Afyonkarahisar region in central Turkey. In this study, the relationships between epipelic diatoms, macrophytes, and the water quality of Akarçay Stream are presented. According to Canonical Correspondence Analysis (CCA), BOD5, COD, TDS, NH4-N, NO2-N, and PO4-P had the most significant effects on the diatom and macrophyte community structures of the stream. According to CCA and Correspondence Analysis (CA), dominant diatom species and macrophytes constituted two groups, eutrophic and polluted. While eutraphentic taxa were abundant among upstream diatoms, hypereutraphentic taxa were found downstream in the Akarçay. The diatom assemblages in the sites upstream were generally characterized by an abundance of β-mesosaprobous and α-mesosaprobous species, while the diatom assemblages downstream had a very high abundance of polisaprobous species. Eutrophic and hypertrophic macrophyte taxa (such as Lemna trisulca, Potamogeton nodosus, and Ranunculus sp.) covered a high percentage of the stream bottom. Both diatom indices and macrophyte indices with the exception of the Biological Macrophyte Index of Rivers (IBMR) were correlated with BOD5, COD, TDS, NH4-N, NO2-N, PO4-P, and EC. Physicochemical variables, diatom and macrophyte taxa and the results of diatom and macrophyte indices indicated that the Akarçay stream basin is eutrophic and organically polluted.
Three positive feedback mechanisms for ice-sheet melting in a warming climate
Authors: Ren Diandong , Leslie Lance M. 
Published: December 2011

AbstractThree positive feedback mechanisms that accelerate ice-sheet melting are assessed in a warming climate, using a numerical ice model driven by atmospheric climate models. The Greenland ice sheet (GrIS) is the modeling test-bed under accelerated melting conditions. The first feedback is the interaction of sea water with ice. It is positive because fresh water melts ice faster than salty water, owing primarily to the reduction in water heat capacity by solutes. It is shown to be limited for the GrIS, which has only a small ocean interface, and the grounding line of some fast glaciers becomes land-terminating during the 21st century. The second positive feedback, strain heating, is positive because it produces further ice heating inside the ice sheet. The third positive feedback, granular basal sliding, applies to all ice sheets and becomes the dominant feedback during the 21st century. A numerical simulation of Jakobshavn Isbræ over the 21st century reveals that all three feedback processes are active for this glacier. Compared with the year 2000 level, annual ice discharge into the ocean could increase by ∼1.4 km3 a−1 (∼5% of the present annual rate) by 2100. Granular basal sliding contributes ∼40% of this increase.
Distribution of debris thickness and its effect on ice melt at Hailuogou glacier, southeastern Tibetan Plateau, using in situ surveys and ASTER imagery
Authors: Zhang Yong , Fujita Koji , Liu Shiyin , Liu Qiao , Nuimura Takayuki 
Published: December 2011

AbstractDebris cover is widely present in glacier ablation areas of the Tibetan Plateau, and its spatial distribution greatly affects glacier melt rates. High-resolution in situ measurements of debris thickness on Hailuogou glacier, Mount Gongga, southeastern Tibetan Plateau, show pronounced inhomogeneous debris distribution. An analysis of transverse and longitudinal profiles indicates that the ground-surveyed debris thicknesses and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER)-derived thermal resistances of debris layers correlate strongly over the entire ablation area. Across- and along-glacier patterns of ASTER-derived thermal resistance correspond well with spatial patterns of debris thickness, which may reflect large-scale variations in the extent and thickness of the debris cover. The ice melt rate variability over the ablation area simulated by a surface energy-balance model that considered thermal resistance of the debris layer indicates clearly the crucial role of debris and its spatial continuity in modifying the spatial characteristics of melt rates. Because of the inhomogeneous distribution of debris thickness, about 67% of the ablation area on Hailuogou glacier has undergone accelerated melting, whereas about 19% of the ablation area has experienced inhibited melting, and the sub-debris melt rate equals the bare-ice melt rate in only 14% of the ablation area.
The chemical forms of water-soluble microparticles preserved in the Antarctic ice sheet during Termination I
Authors: Sakurai Toshimitsu , Ohno Hiroshi , Horikawa Shinichiro , Iizuka Yoshinori , Uchida Tsutomu , Hirakawa Kazuomi , Hondoh Takeo 
Published: December 2011

AbstractThis study clarifies changes in the chemical forms of microparticles during Termination I, the period of drastic climate change between the Last Glacial Maximum (LGM) and the Holocene. We determine the chemical forms of individual water-soluble microparticles through micro-Raman spectroscopy and compare the relative frequencies of different types with the ion concentrations in melted ice. Micro-Raman spectroscopy shows that Na2SO4·10H2O and MgSO4·11H2O are abundant in Holocene ice, while CaSO4·2H2O and other salts are abundant in LGM ice. Further, the number of CaSO4·2H2O particles is strongly correlated with the concentration of Ca2+ during Termination I. Taken together, the evidence strongly suggests that most of the Ca2+ exists as CaSO4·2H2O. The different compositions of microparticles from the Holocene and LGM can be explained by ion balance arguments.
Modeling 5 years of subglacial lake activity in the MacAyeal Ice Stream (Antarctica) catchment through assimilation of ICESat laser altimetry
Authors: Carter Sasha P. , Fricker Helen A. , Blankenship Donald D. , Johnson Jesse V. , Lipscomb William H. , Price Stephen F. , Young Duncan A. 
Published: December 2011

AbstractSubglacial lakes beneath Antarctica’s fast-moving ice streams are known to undergo ∼1 km3volume changes on annual timescales. Focusing on the MacAyeal Ice Stream (MacIS) lake system, we create a simple model for the response of subglacial water distribution to lake discharge events through assimilation of lake volume changes estimated from Ice, Cloud and land Elevation Satellite (ICESat) laser altimetry. We construct a steady-state water transport model in which known subglacial lakes are treated as either sinks or sources depending on the ICESat-derived filling or draining rates. The modeled volume change rates of five large subglacial lakes in the downstream portion of MacIS are shown to be consistent with observed filling rates if the dynamics of all upstream lakes are considered. However, the variable filling rate of the northernmost lake suggests the presence of an undetected lake of similar size upstream. Overall, we show that, for this fast-flowing ice stream, most subglacial lakes receive >90% of their water from distant distributed sources throughout the catchment, and we confirm that water is transported from regions of net basal melt to regions of net basal freezing. Our study provides a geophysically based means of validating subglacial water models in Antarctica and is a potential way to parameterize subglacial lake discharge events in large-scale ice-sheet models where adequate data are available.
A compact lightweight multipurpose ground-penetrating radar for glaciological applications
Authors: Vasilenko E.V. , Machío F. , Lapazaran J.J. , Navarro F.J. , Frolovskiy K. 
Published: December 2011

AbstractWe describe a compact lightweight impulse radar for radio-echo sounding of subsurface structures designed specifically for glaciological applications. The radar operates at frequencies between 10 and 75 MHz. Its main advantages are that it has a high signal-to-noise ratio and a corresponding wide dynamic range of 132 dB due mainly to its ability to perform real-time stacking (up to 4096 traces) as well as to the high transmitted power (peak voltage 2800 V). The maximum recording time window, 40 μs at 100 MHz sampling frequency, results in possible radar returns from as deep as 3300 m. It is a versatile radar, suitable for different geophysical measurements (common-offset profiling, common midpoint, transillumination, etc.) and for different profiling set-ups, such as a snowmobile and sledge convoy or carried in a backpack and operated by a single person. Its low power consumption (6.6 W for the transmitter and 7.5 W for the receiver) allows the system to operate under battery power for >7 hours with a total weight of <9 kg for all equipment, antennas and batteries.
Improvements to shear-deformational models of glacier dynamics through a longitudinal stress factor
Authors: Adhikari Surendra , Marshall Shawn J. 
Published: December 2011

AbstractIn a two-dimensional (plane strain) glacier domain, gravity-driven ice flow is balanced by basal drag and the resistance associated with longitudinal stress gradients. The plane strain Stokes model accommodates both these resistances, whereas several simpler models only account for basal drag. Solving the Stokes equations is numerically challenging and computationally expensive, but simpler models may lead to unrealistic dynamical behaviour. Here, we propose a factor which can be introduced in shear-deformational flow models to yield results comparable to those from the plane strain Stokes model. As this factor adapts simpler models to capture the effects of missing dynamics, i.e. longitudinal stress gradients, we refer to it as the longitudinal stress (L-)factor. We assess the usefulness of this factor for idealized domains with complex basal topography and evolving geometry. We apply the model to Haig Glacier, Canadian Rockies, in order to present an illustration of how simulations of glacier response to climate forcing can be improved through the introduction of the L-factor in a shear-deformational flow model.
Prospective, Randomized, Double-blind, Contralateral Eye Comparison of Myopic LASIK With Optimized Aspheric or Prolate Ablations
Authors: Chayet Arturo , Bains Harkaran S. 
Published: December 2011

PURPOSE:
To compare the postoperative outcomes of aspheric or prolate LASIK for myopia and myopic astigmatism.

METHODS:

In this double-blind, bilateral, randomized trial, 40 patients (80 eyes) with −0.75 to −7.00 diopters (D) of manifest refraction spherical equivalent (MRSE) underwent optimized aspheric treatment zone ablation (OATz group) in 1 eye and optimized prolate ablation (OPA group) in the fellow eye. Six-month postoperative outcomes were compared for MRSE and visual acuity, contrast sensitivity, patient satisfaction, ocular higher order aberrations (HOAs), and spherical aberration. The Wilcoxon signed rank test, Mann-Whitney U test, and paired
t
test were used for testing differences between groups.
P
<.05 was statistically significant. Main outcome measures included HOAs, spherical aberration, visual and refractive outcomes, and contrast sensitivity.

RESULTS:

Postoperatively, 36 patients (72 eyes) were evaluated. The MRSE was −0.07±0.23 D for the OPA group and +0.02±0.24 D for the OATz group (
P
>.05). Two (5%) eyes in the OPA group and 1 (3%) eye in the OATz group (
P
=.114) lost 1 line of corrected distance visual acuity. Postoperative visual acuity was not statistically different between groups (
P
>.05). Statistically lower change was noted in spherical aberration (0.011 μm) in the OPA group versus the OATz group (0.099 μm) (
P
<.001). Statistically higher induction of coma was noted in the OPA group (
P
=.035). No statistically significant differences were noted in photopic, mesopic, or glare contrast sensitivity and patient satisfaction between groups (
P
>.05, for all comparisons).

CONCLUSIONS:
The refractive and visual outcomes of OPA and OATz were equivalent. However, the postoperative optical quality of OPA-treated eyes was better.
Corporate governance and efficiency in the Electricity Sector using Data Envelopment Analysis: a study in the brazilian stock market
Authors: Peixoto Fernanda Maciel , Ferreira Roberto do Nascimento , Lopes Ana Lúcia Miranda , Fagundes André Francisco Alcântara 
Published: December 2011

Different Corporate Governance mechanisms have been suggested to minimize agency problems between managers and shareholders, and between controlling and minority shareholders. The aim of this study is to analyze the corporate governance mechanisms result in greater efficiency for Brazilian stock companies in the electricity sector, in 2007-2009. The hypothesis to be verified is that the lower the voting concentration and the dependence of the council, and the greater the cash flow concentration, the greater the performance of the company will be. The analyzed sample involved thirty-three companies, fourteen being classified into one of the levels of CG (Level 1, Level 2 or New Market) and the remainder being members of the traditional market. To measure the efficiency of the companies, the non-parametric DEA (Data Envelopment Analysis) method was used, and to relate the efficiency with the governance variables, we adopted regression analysis of panel data. The results demonstrated that the use of CG mechanisms positively influences business efficiency, but not in the expected magnitude. It was found that the cash flow concentration is positively related to the efficiency of firms, supporting the governance literature. For future work, the use of other input and output variables is suggested.
Associations between frontal plane joint stiffness and proprioceptive acuity in knee osteoarthritis
Authors: Cammarata Martha L. , Dhaher Yasin Y. 
Published: December 2011

AbstractObjectiveIt has been proposed that proprioceptive impairments observed in knee osteoarthritis (OA) may be associated with disease‐related changes in joint mechanics. The aim of this study was to quantify joint proprioception and stiffness in the frontal plane of the knee in persons with and without knee OA and to report the associations between these 2 metrics.MethodsParticipants were 13 patients with knee OA and 14 healthy age‐matched subjects. Proprioceptive acuity was assessed in varus and valgus using the threshold to detection of passive movement (TDPM) test. Passive joint stiffness was estimated as the slope of the normalized torque‐angle relationship at 0° joint rotation (neutral) and several rotations in varus and valgus. Analyses of variance were performed to determine the effect of OA and sex on each metric. Linear regression was used to assess the correlation between the TDPM and joint stiffness.ResultsThe TDPM was significantly higher (P < 0.05) in the OA group compared to the control group for both varus and valgus, but significant sex differences were observed. Passive joint stiffness was significantly reduced (P < 0.05) in OA participants compared to the control group in neutral and valgus, but not varus, and significantly reduced in women compared to men. A weak negative correlation was observed between the TDPM and stiffness estimates, suggesting that poorer proprioception was associated with less joint stiffness.ConclusionWhile both joint stiffness and proprioception were reduced in the OA population, they were only weakly correlated. This suggests that other neurophysiologic factors play a larger role in the proprioceptive deficits in knee OA.
Layer‐by‐Layer Assembly Through Weak Interactions and Their Biomedical Applications
Authors: Matsusaki Michiya , Ajiro Hiroharu , Kida Toshiyuki , Serizawa Takeshi , Akashi Mitsuru 
Published: December 2011

AbstractThe surface design and control of substrates with nanometer‐ or micrometer‐sized polymer films are of considerable interest for both fundamental and applied studies in the biomedical field because of the required surface properties. The layer‐by‐layer (LbL) technique was discovered in 1991 by Decher and co‐workers for the fabrication of polymer multilayers constructed mainly through electrostatic interaction. The scope and applicability of this LbL assembly has been extended by introducing molecularly regular conformations of polymers or proteins by employing, for the first time, weak interactions such as van der Waals interactions and biological recognition. Since these weak interactions are the sum of the attractive or repulsive forces between parts of the same molecule, they allow macromolecules to be easily arranged into the most stable conformation in a LbL film. By applying this characteristic feature, the template polymerization of stereoregular polymers, stereoregular control of surface biological properties, drastic morphological control of biodegradable nano materials, and the development of three‐dimensional cellular multilayers as a tissue model were successfully achieved. It is expected that LbL assembly using weak interactions will promote further interest into fundamental and applied studies on the design of surface chemistry in the biomedical field.
Bending the prescription opioid dosing and mortality curves: Impact of the Washington State opioid dosing guideline
Authors: Franklin Gary M. , Mai Jaymie , Turner Judith , Sullivan Mark , Wickizer Thomas , Fulton‐Kehoe Deborah 
Published: December 2011

AbstractBackgroundOpioid use and dosing for patients with chronic non‐cancer pain have dramatically increased over the past decade, resulting in a national epidemic of mortality associated with unintentional overdose, and increased risk of disability among injured workers. We assessed changes in opioid dosing patterns and opioid‐related mortality in the Washington State (WA) workers' compensation system following implementation of a specific WA opioid dosing guideline in April, 2007.MethodsUsing detailed computerized billing data from WA workers' compensation, we report overall prevalence of opioid prescriptions, average morphine‐equivalent dose (MED)/day, and proportion of workers on disability compensation receiving opioids and high‐dose (≥120 mg/day MED) opioids over the past decade. We also report the trend of unintentional opioid deaths during the same time period.ResultsCompared to before 2007, there has been a substantial decline in both the MED/day of long‐acting DEA Schedule II opioids (by 27%) and the proportion of workers on doses ≥120 md/day MED (by 35%). There was a 50% decrease from 2009 to 2010 in the number of deaths.ConclusionsThe introduction in WA of an opioid dosing guideline appears to be associated temporally with a decline in the mean dose for long‐acting opioids, percent of claimants receiving opioid doses ≥120 mg MED per day, and number of opioid‐related deaths among injured workers. Am. J. Ind. Med. 55:325–331, 2012. © 2011 Wiley Periodicals, Inc.
Capacity building in environmental and occupational health in Sri Lanka
Authors: Wickremasinghe Ananda R. , Peiris‐John Roshini , Nandasena Sumal , Delzell Elizabeth , Tipre Meghan , Sathiakumar Nalini 
Published: December 2011

AbstractBackgroundAlthough environmental and occupational health (EOH) research and services in Sri Lanka have a long history, policies related to EOH are outdated.MethodsWe review the International Training and Research in Environmental and Occupational Health (ITREOH) program in Sri Lanka that commenced in 2006 as a collaboration between the University of Alabama at Birmingham and the Faculty of Medicine of the University of Kelaniya, Sri Lanka.ResultsThe program has trained over 20 scientists in conducting EOH research. New pioneering research in EOH was initiated. The program was instrumental in furthering the training and research in EOH by initiating a MPH degree program, the first in the country.ConclusionsThe program has established North–South, South–South and in‐country collaborations between institutions and scientists, increasing the visibility of EOH in the future. Am. J. Ind. Med. 56:1–10, 2013. © 2011 Wiley Periodicals, Inc.
Longitudinal mental health impact among police responders to the 9/11 terrorist attack
Authors: Bowler Rosemarie M. , Harris Matthew , Li Jiehui , Gocheva Vihra , Stellman Steven D. , Wilson Katherine , Alper Howard , Schwarzer Ralf , Cone James E. 
Published: December 2011

AbstractBackgroundAmong police responders enrolled in the World Trade Center Health Registry (WTCHR), Post‐traumatic Stress Disorder (PTSD) was almost twice as prevalent among women as men 2–3 years after the 9/11 attacks.MethodsPolice participants in the WTCHR Wave 1 survey 2–3 years after 9/11/01, were reassessed for probable PTSD at Wave 2, 5–6 years after 9/11/01, using PCL DSM‐IV criteria.ResultsPolice participants in the Wave 2 survey included 2,527 men, 413 women. The prevalence of “Probable PTSD” was 7.8% at Wave 1 and 16.5% at Wave 2. Mean PCL scores increased from 25.1 to 29.9 for men and 28.6 to 32.2 for women. Prevalence of PTSD was higher for women than for men at Wave 1 (χ2 = 10.882, P = 0.002), but not Wave 2 (χ2 = 2.416, P = 0.133). Other risk factors included losing one's job after 9/11 and being disabled.ConclusionsPrevalence of probable PTSD among police doubled between 2003–2004 and 2006–2007. After the 2‐year time span, the gender difference was no longer significant; prevalence of PTSD symptoms increased and there was a substantial amount of co‐morbidity with other mental health problems. Further development of prevention and intervention strategies for police responders with symptoms of PTSD is needed. The observed upward trend in PCL scores over time in police officers with PCL scores less than 44, suggests that PTSD prevention and intervention strategies should be applied to all police affected by the 9/11 attacks, not limited just to those with PTSD symptoms. Am. J. Ind. Med. 55:297–312, 2012. © 2011 Wiley Periodicals, Inc.
Comparison of risk factors for shoulder pain and rotator cuff syndrome in the working population
Authors: Bodin Julie , Ha Catherine , Chastang Jean‐François , Descatha Alexis , Leclerc Annette , Goldberg Marcel , Imbernon Ellen , Roquelaure Yves 
Published: December 2011

AbstractBackgroundTo compare risk factors for shoulder pain without and with rotator cuff syndrome (RCS).MethodsA total of 3,710 workers of a French region were randomly included in the cross‐sectional study between 2002 and 2005. Personal and occupational risk factors were assessed during a physical examination and by a self‐administered questionnaire. Multinomial logistic modeling was used for the following outcomes: no shoulder pain and no RCS (reference), shoulder pain without RCS (called “shoulder pain”) and RCS, separately for men and women.ResultsThe prevalence rates of “shoulder pain” for men and women were 28.0% and 31.1%, respectively, and the prevalence rates of RCS were 6.6% and 8.5%, respectively. In men, “shoulder pain” and RCS were associated with age, high‐perceived physical exertion, and arm abduction. Automatic work pace and low supervisor support were associated with “shoulder pain,” and high psychological demand and low skill discretion with RCS. In women, “shoulder pain” and RCS were associated with age, repetitiveness of tasks, and low supervisor support. High perceived physical exertion and exposure to cold temperatures were associated with “shoulder pain.”ConclusionsAge was more strongly associated with RCS than with shoulder pain without RCS for both genders. Biomechanical and psychosocial factors were associated with “shoulder pain” and RCS and differed between genders. Am. J. Ind. Med. 55:605–615, 2012. © 2011 Wiley Periodicals, Inc.