bluuebunny/crossref_metadata_2025 huggingface dataset:
An Ex Vivo Biomechanical Study Comparing Strength Characteristics of a New Technique with the Three‐Loop Pulley for Equine Tenorrhaphy
Authors: Smith Rachael L. , Murphy David J. , Day Robert E. , Lester Guy D.
Published: July 2011

Objective: To test single cycle to failure tensile strength characteristics of 6 suture material–pattern combinations in equine superficial digital flexor (SDF) tenorrhaphy, specifically to compare a 10‐strand modification of the Savage core suture technique with the 3‐loop pulley technique.

Study Design: Ex vivo mechanical experiment comparing 3 different suture patterns with 2 different materials.

Sample Population: Forelimb and hindlimb SDF tendons (n=48) harvested from adult Thoroughbred and Standardbred horses of mixed age and gender.

Methods: Six suture material–pattern combinations were evaluated: (1) 10‐strand Savage, size 2 polydioxanone (PDS); (2) 10‐strand Savage, size 2 polyglactin 910 (PG910); (3) 10‐strand Savage, size 2 PDS with Lin‐locking epitenon suture, size 2–0 PDS; (4) 10‐strand Savage size 2 PG910 with Lin‐locking epitenon suture, size 2–0 PDS; (5) 3‐loop pulley, size 2 PDS; and (6) 3‐loop pulley, size 2 PG910. Maximum load at failure (N), gap at failure (mm), and mode of failure (suture breakage or pull through) were evaluated for each of the 6 suture material–pattern combinations and underwent statistical analysis to determine significance of differences and interactions of the measured data.

Results: The 10‐strand Savage technique failed at a mean load of 872 N (804–939, 95% CI). The 10‐strand Savage with Lin‐locking failed at a significantly greater mean load of 998 N (930–1065, 95% CI). The 3‐loop pulley pattern failed with a mean load of 337 N (270–405, 95% CI). There were significant interactions between the technique and suture material used.

Conclusion: The 10‐strand Savage technique for repair of transected cadaver SDF tendons has superior strength characteristics with or without the epitenon suture when compared to the 3‐loop pulley. Suture material and pattern interactions were observed with PG 910 conferring higher strength for the 10‐strand Savage whereas PDS did so for the 3‐loop pulley.
Resistance to Subsidence of an Uncemented Femoral Stem After Cerclage Wiring of a Fissure
Authors: McCulloch Ryan S. , Roe Simon C. , Marcellin‐Little Denis J. , Mente Peter L.
Published: July 2011

Objective

To compare: (1) the force required to initiate subsidence, and (2) the relative subsidence, of femoral stems implanted into intact femora, and then into the same femora in which an induced fissure had been stabilized by cerclage.

Study Design

In vitro, mechanical study.

Sample Population

Femora (n=9) from 9 dogs.

Methods

Femora were prepared for implantation of an uncemented stem. Stems were implanted with continuous and impact loading. After axial loading until a fissure occurred, the stems were extracted, and the fissure stabilized with double‐loop cerclage. Stems were reimplanted, and reloaded to failure.

Results

Mean±SD load to initiate subsidence in intact femora was 1706±584 N compared with 2379±657 N for cerclaged bones (P=.002). Mean relative subsidence of intact femora was 3.99±2.09 mm compared with 1.79±2.99 mm for cerclaged bones (P=.091).

Conclusions

The load to initiate subsidence is increased in femora that have fissured, then have been stabilized with double‐loop cerclage, when compared with intact femora. The relative subsidence is not different between intact and stabilized specimens.
Comparison of Computed Tomographic and Radiographic Popliteal Lymphangiography in Normal Dogs
Authors: Singh Ameet , Brisson Brigitte A. , Nykamp Stephanie , O'Sullivan M. Lynne
Published: July 2011

Objective:To (1) describe computed tomographic (CT) popliteal lymphangiography; (2) compare the number of thoracic duct (TD) branches detected by CT and by radiography after popliteal lymphangiography; and (3) to compare the number of branches detected after left and right popliteal lymphangiography.

Study Design:Experimental study.

Animals:Adult dogs (n=6).

Methods:A randomly selected popliteal lymph node was percutaneously injected with 12 mL iodinated contrast medium through a 25‐g butterfly catheter over 4–5 minutes. Lateral and ventrodorsal (VD) thoracic radiograph projections and thoracic CT were performed. The procedure was repeated using the contralateral lymph node after a 48–72 hours washout period.

Results:One dog had TD branches visible on CT but not on radiographs. A significantly greater number of TD branches were observed with CT popliteal lymphangiography compared with lateral and VD radiographic popliteal lymphangiography (P=.003 andP<.001, respectively). The number of visible TD branches observed between the 6th thoracic and 1st lumbar vertebrae were not significantly different in these dogs (P=.146). A significant difference in number of TD branches observed was not found after left or right popliteal lymph node injection (P=.097).

Conclusions:CT popliteal lymphangiography consistently identified a greater number of TD branches when compared with radiographic popliteal lymphangiography. Injection of either popliteal lymph node resulted in the same number of TD branches being observed.
Endoscope‐Assisted Thoracolumbar Lateral Corpectomy
Authors: Carozzo Claude , Maitre Pierre , Genevois Jean‐Pierre , Gabanou Pierre‐Alexandre , Fau Didier , Viguier Eric
Published: July 2011

Objective: To report an endoscope‐assisted lateral approach to expose the intervertebral foramen and disk and perform lateral corpectomy of thoracolumbar disks in dogs.

Study Design: Cadaver study.

Animals: Fresh canine cadavers (n=6).

Methods: A thoracic (T10–T11) and a lumbar (L3–L4) lateral approach were made on 6 fresh canine mixed breed cadavers. Through a limited skin incision, musculature was dissected and retracted using a neurosurgical self‐retaining retractor and lateral corpectomy performed. The approach and bone removal, both performed under endoscopic control, were assessed.

Results: The foramen and intervertebral disk were clearly observed in all specimens without any iatrogenic injury of the ventral and dorsal nerve branches. Access to the foramen was possible in all specimens; in the thoracic area the head of the rib was always partially excised to observe the intervertebral disk medially. Lateral corpectomy was easily performed in all cadavers and spinal cord observation was good. Extension to foraminotomy or mini hemilaminectomy could easily be performed through the same limited approach.

Conclusion: Endoscopic exploration provided a good viewing of the intervertebral disk and/or foramen. An endoscope‐assisted thoracolumbar lateral corpectomy could effectively be performed through a limited approach to the thoracolumbar disks and allowed good ventral spinal cord assessment.
Computed Tomography or Magnetic Resonance Imaging‐Assisted Partial Hoof Wall Resection for Keratoma Removal
Authors: Getman Liberty M. , Davidson Elizabeth J. , Ross Michael W. , Leitch Midge , Richardson Dean W.
Published: July 2011

Objectives: To (1) describe the computed tomography (CT) and magnetic resonance imaging (MRI) appearance of keratomas; (2) describe a CT‐ or MRI‐assisted partial hoof wall resection technique for removal of keratomas; and (3) evaluate the morbidity and postoperative outcome of these horses.

Study Design: Case series.

Animals: Horses (n=10) with keratoma.

Methods: Data retrieved from medical records included signalment, lameness duration and grade, physical and diagnostic evaluation findings, CT and MRI technique and findings, surgical details, histopathologic diagnosis, postoperative treatment, and complications experienced. Long‐term outcome was obtained by telephone interviews of owners.

Results: Complications including excessive granulation tissue formation and infection were seen in 2 horses (20%). No keratoma recurrence occurred. Follow‐up information was available for 8 horses; 7 were sound and had resumed work. Mean time until they became sound was 2.7 months, and mean time until work resumed was 3.6 months.

Conclusions: CT and MRI can be used to accurately identify the location of keratomas. Postoperative complications may be decreased by creating smaller hoof wall defects, filling the defects with antimicrobial‐impregnated polymethylmethacrylate, and placing a shoe early in the postoperative period.
Who Drove and Burst the Tech Bubble?
Authors: GRIFFIN JOHN M. , HARRIS JEFFREY H. , SHU TAO , TOPALOGLU SELIM
Published: July 2011

From 1997 to March 2000, as technology stocks rose more than five‐fold, institutions bought more new technology supply than individuals. Among institutions, hedge funds were the most aggressive investors, but independent investment advisors and mutual funds (net of flows) actively invested the most capital in the technology sector. The technology stock reversal in March 2000 was accompanied by a broad sell‐off from institutional investors but accelerated buying by individuals, particularly discount brokerage clients. Overall, our evidence supports the bubble model of Abreu and Brunnermeier (2003), in which rational arbitrageurs fail to trade against bubbles until a coordinated selling effort occurs.
Individual Investors and Volatility
Authors: FOUCAULT THIERRY , SRAER DAVID , THESMAR DAVID J.
Published: July 2011

We show that retail trading activity has a positive effect on the volatility of stock returns, which suggests that retail investors behave as noise traders. To identify this effect, we use a reform of the French stock market that raises the relative cost of speculative trading for retail investors. The daily return volatility of the stocks affected by the reform falls by 20 basis points (a quarter of the sample standard deviation of the return volatility) relative to other stocks. For affected stocks, we also find a significant decrease in the magnitude of return reversals and the price impact of trades.
Stressed, Not Frozen: The Federal Funds Market in the Financial Crisis
Authors: AFONSO GARA , KOVNER ANNA , SCHOAR ANTOINETTE
Published: July 2011

We examine the importance of liquidity hoarding and counterparty risk in the U.S. overnight interbank market during the financial crisis of 2008. Our findings suggest that counterparty risk plays a larger role than does liquidity hoarding: the day after Lehman Brothers' bankruptcy, loan terms become more sensitive to borrower characteristics. In particular, poorly performing large banks see an increase in spreads of 25 basis points, but are borrowing 1% less, on average. Worse performing banks do not hoard liquidity. While the interbank market does not freeze entirely, it does not seem to expand to meet latent demand.
Presidential Address: Discount Rates
Authors: COCHRANE JOHN H.
Published: July 2011

Discount‐rate variation is the central organizing question of current asset‐pricing research. I survey facts, theories, and applications. Previously, we thought returns were unpredictable, with variation in price‐dividend ratios due to variation in expected cashflows. Now it seems all price‐dividend variation corresponds to discount‐rate variation. We also thought that the cross‐section of expected returns came from the CAPM. Now we have a zoo of new factors. I categorize discount‐rate theories based on central ingredients and data sources. Incorporating discount‐rate variation affects finance applications, including portfolio theory, accounting, cost of capital, capital structure, compensation, and macroeconomics.
Europium‐Doped LaSi3N5 Ternary Nitride: Synthesis, Spectroscopy, Computed Electronic Structure and Band Gaps
Authors: Benco Ľubomír , Lenčéš Zoltán , Šajgalík Pavol , Jáné Eduard , Velič Dušan
Published: July 2011

Europium‐doped LaSi3N5 phosphor synthesized from LaSi/Si/Si3N4/Eu2O3 mixture by direct nitridation at 1390°C and additional annealing at 1630°C for 3 h shows emissions in the green light region. With increasing europium content in the general formula La1‐zEuzSi3N5‐zO1.5z from z = 0.04 to 0.063 the emission intensity increases. The two maxima of the excitation band for the 6.3 mol% Eu‐doped LaSi3N5 are at ~4.0 and ~3.35 eV. First‐principles density‐functional theory (DFT) calculations are performed to enhance the understanding of the electronic structure of the stoichiometric LaSi3N5 and La/Eu and N/O substituted ternary nitrides. To mimic the realistic concentration of Eu and O the cell volume is expanded to the 2 × 1 × 2 super‐cell with 144 atoms. Electronic structure and band gaps are calculated using both the plain DFT and the hybrid functional. Three different doping schemes are investigated combining the La3+/Eu3+, La3+/□, La3+/Eu2+ substitutions in cation sites (□ = cation vacancy) and the N3−/O2− substitution in the framework. The La3+/Eu3+ substitution does not lead to a significant change of the gap. The La3+/Eu2+ substitution introduces a narrow band of Eu 4f‐states in the gap thus narrowing the band gap. The calculated value of ~3.23 eV by the hybrid functional is in reasonable agreement with experimental data.
Thermal Stability of the Cement Sheath in Steam Treated Oil Wells
Authors: Makar Jon , Luke Karen
Published: July 2011

Considerable work has been done on the phase equilibria and physical properties of thermal cements heated directly to high temperatures. In thermal recovery oil wells the cement sheath is, however, cured for days to years at temperatures of 40°C or less before it is subjected to steam injection temperatures of up to about 320°C. The effects of this alternative curing regime have not been well documented. Here, the impact of pre‐curing samples for 1, 14, and 28 days at 35°C before heating to 230°C on phase assemblages, morphologies, and physical properties of thermal cement were investigated. Control samples included thermal cements heated directly to high temperature as well as samples cured only at 35°C. Xonotlite formed the predominant phase in the pre‐cured thermal cements instead of the tobermorite found in the control sample heated directly to 230°C. Although all pre‐cured samples were predominantly xonotlite, their morphological characteristics of the phase assemblages were found to vary distinctly with pre‐curing time. Significant differences between the pre‐cured and directly cured samples were also observed in terms of porosity, permeability, and mechanical behavior.
Influence of Ag2O in Physico‐Chemical Properties and HAp Precipitation on Phosphate‐Based Glasses
Authors: Rajkumar Gurusamy , Rajkumar Mani , Rajendran Venkatachalam , Aravindan Samickannian
Published: July 2011

Phosphate‐based glass systems with different Ag2O contents 45P2O5–30CaO–(25‐x)Na2O–xAg2O (x = 0, 0.25, 0.5, 0.75, and 1.0, hereafter termed, respectively, as PCNA0, PCNA0.25, PCNA0.5, PCNA0.75, and PCNA1) are prepared by keeping the ratio of P/Ca as 3.0. The influence of Ag2O on phosphate glass system is studied in terms of ultrasonic parameters, pH and in vitro studies. The structural role of Ag2O, i.e., loose packing of glass network is noticed up to 0.5 mol% of Ag2O content and then by an increase in packing density with further addition of Ag2O. The hydroxyapatite (HAp) forming ability of prepared glasses is carried through in vitro studies in simulated body fluid. The scanning electron microscopy images before and after in vitro studies show the formation of a low concentration of HAp in all glass surfaces except PCNA1, whereas a higher rate of formation of HAp is evidenced on PCNA1 glass sample. The Fourier Transform Infrared spectra and X‐ray Diffraction patterns that are observed support higher bioactivity on PCNA1 glass sample.
New Microwave Dielectric Ceramics BaLn2(MoO4)4 (Ln = Nd and Sm) with Low Loss
Authors: Zhou Di , Pang Li‐Xia , Guo Jing , Wu Ying , Zhang Gao‐Qun , Dai Wei , Wang Hong , Yao Xi
Published: July 2011

In the present work, a pure monoclinic phase of BaNd2(MoO4)4 and BaSm2(MoO4)4 was formed at 850°C and 600°C, respectively, via a solid‐state reaction method. The ceramic samples were found to be well densified at 960°C. Dense and homogeneous microstructures were revealed from the scanning electron microscopy. The microwave dielectric behaviors were studied as a function of sintering temperature and characterized in the temperature range 25°C–120°C. The best properties were obtained in ceramics sintered at 960°C with a permittivity ~11.7, a Q × f value of 45 000 GHz and a temperature coefficient of frequency about −41 ppm/°C for BaNd2(MoO4)4 ceramic at 9.9 GHz, and a permittivity ~11.8, a Q × f value of 20 000 GHz, and a temperature coefficient of frequency about −34 ppm/°C for BaSm2(MoO4)4 ceramic at 9.7 GHz, respectively.
Effect of Crack Pattern on the Residual Strength of Ceramics After Quenching
Authors: Shao Yingfeng , Zhang Yue , Xu Xianghong , Zhou Zhiliang , Li Wei , Liu Boyang
Published: July 2011

The physical mechanisms between residual strength and crack characteristic of ceramics after water‐quenching are studied by statistically measuring the cracks in ceramic sheet. The result herein reveals that in the joint action of long crack length and density, the residual strength is maintained at the same level within a temperature range above the critical thermal shock temperature difference (ΔTC). The result presented herein forms a further comprehension to the ceramics behaviors of and the theoretical approaches to thermal shock.
High Field Emission Performance of Needle‐on‐Fiber Hierarchical‐Structure ZnO
Authors: Liu Yanxia , Xie Yizhu , Chen Jiangtao , Liu Jing , Gao Caitian , Yun Chao , Lu Bingan , Xie Erqing
Published: July 2011

Hierarchical‐structure ZnO consisting of ZnO nanoneedles on ZnO nanofibers was fabricated by a two‐step procedure – first electrospinning and then aqueous solution processes. Field emission (FE) property of the needle‐on‐fiber hierarchical‐structure ZnO was tested. The low turn‐on field of the field emission at 4.8 V/μm was obtained with the current density of 10 μA/cm2. The field enhancement factor was estimated as high as 3400. Such high FE performances of the hierarchical‐structure ZnO derived from the tapered‐tip structure of the ZnO nanoneedles, the high aspect ratio of the hierarchical structure and the undulant space distribution of the ZnO nanoneedles. These results would benefit the potential application of the hierarchical‐structure ZnO in cold‐cathode‐based devices.
Competent Enough, But Would YouVotefor Her? Gender Stereotypes and Media Influences on Perceptions of Women Politicians
Authors: BLIGH MICHELLE C. , SCHLEHOFER MICHÈLE M. , CASAD BETTINA J. , GAFFNEY AMBER M.
Published: July 2011

Though research has demonstrated that media coverage of men and women politicians differ, fewer studies have examined the dual influence of gender stereotypes and types of media coverage in influencing public perceptions of women politicians. Study 1 (N = 329) examined how pre‐existing attitudes toward women leaders and valence of media message impacted perceptions of a woman senator and evaluations of the media source. Study 2 (N = 246) explored how media focus on a woman politician's personality or ability impacted perceptions of her warmth/likability and competence. Results suggest the media has particular influence on judgments of women politicians' likability (the “competent but cold” effect), providing evidence that women politicians need to be vigilant in monitoring their media depictions.
Driving Under the Influence (of Mass Media): A Four‐Year Examination of NASCAR and West Virginia Aggressive‐Driving Accidents and Injuries1
Authors: VITAGLIONE GUY D.
Published: July 2011

To assess the impact of televised, competitive, dangerous automobile racing (NASCAR) mass media on viewers' driving behaviors, all automobile accidents and injuries as a result of aggressive driving on file at the West Virginia Division of Highways for the years 2003 through 2006 were subjected to a regression analysis controlling for confounding variables, such as weather and road conditions. While the number of accidents declined on the day of the televised events, the number of accidents and injuries increased 5 days following the events. A priming theory of mass‐media influence is discussed.
Liberalización comercial, empleo y desigualdad en la India y Sudáfrica
Authors: KUCERA David , RONCOLATO Leanne
Published: July 2011

Los autores se valen de matrices de contabilidad social junto con un modelo de multiplicadores de Leontief para calcular los efectos de la expansión del comercio exterior en el empleo y los ingresos de la India y Sudáfrica. Estudian el período de rápida liberalización comercial que comenzó a principios del decenio de 1990, distinguiendo entre el comercio con los países desarrollados y con los países en desarrollo. Averiguan qué ramos han ganado y cuáles han perdido puestos de trabajo, así como los sesgos por sexo y por nivel de cualificación profesional. También analizan la desigualdad de ingresos de los hogares rurales y urbanos. Sus resultados se inscriben en la teoría del comercio por lo que se refiere a los mecanismos de ajuste comercial y a las consecuencias de la especialización en el desarrollo económico.
Labor de las administraciones del trabajo del África subsahariana y actualidad del Convenio núm. 150
Authors: AUVERGNON Philippe , LAVIOLETTE Sandrine , OUMAROU Moussa
Published: July 2011

Los autores hacen balance del cumplimiento de los principios del Convenio de la OIT sobre la administración del trabajo, 1978 (núm. 150), en un grupo seleccionado de países africanos. Se basan para ello en las legislaciones nacionales y en observaciones sobre el terreno. Los tres ejes de su investigación son: el peso relativo de las diversas funciones de esta administración; la atención que presta la misma a los trabajadores no asalariados, y la escasez de los recursos humanos y materiales disponibles. Como conclusión subrayan la actualidad y modernidad de este instrumento, sobre todo para la extensión de las actividades de la administración del trabajo al sector informal.
Transición del mercado laboral, desigualdad de ingresos y crecimiento económico de China
Authors: LU Ming , GAO Hong
Published: July 2011

Desde su apertura económica de 1978, China sigue una estrategia de desarrollo que causa desequilibrios internos y externos, sobre todo a partir de la reforma laboral realizada en el decenio de 1990, que impulsó la migración del campo a la ciudad. El trabajo barato se convirtió en la gran baza de la economía nacional, pero la crisis económica mundial de 2008 puso crudamente de manifiesto que ésta dependía en demasía de las exportaciones. Este factor, unido al agravamiento de las disparidades de ingresos, puede poner en peligro el crecimiento del país a no ser que se ajusten las estrategias de reforma y desarrollo a fin de fomentar la igualación de los ingresos y el consumo interno. La Ley del Contrato de Trabajo promulgada en 2008 podría entrañar un cambio por el buen camino.
De la búsqueda de empleo al ascenso. Experiencias de las minorías étnicas en Pekín
Authors: HASMATH Reza
Published: July 2011

Valiéndose de datos del censo y de entrevistas personales, el autor estudia las experiencias laborales de los trabajadores y solicitantes de empleo de Pekín pertenecientes a minorías étnicas. Los datos del mercado de trabajo indican que estas personas se hallan en desventaja respecto de la etnia han, que es la dominante, sobre todo en el acceso a los puestos más cualificados y mejor remunerados. Las comprobaciones del autor dejan entrever que ello puede achacarse a las lagunas de que adolece el orden laboral y que fomentan la dependencia de las redes sociales en este terreno.
Can a breakdown in competition–colonization tradeoffs help explain the success of exotic species in the California flora?
Authors: Molina‐Montenegro Marco A. , Cleland Elsa E. , Watts Sean M. , Broitman Bernardo R.
Published: July 2011

Determining combinations of functional traits that allow a species to colonize new habitats has been central in the development of invasion ecology. Species able to establish in new communities harbor abilities or traits that allow them to use resources or tolerate stress in ways that native species cannot. Tradeoffs among species functional traits along the competition–colonization (CC) continuum, where competitive ability is a decreasing function of dispersal capacity, may allow invasive species to establish themselves in new habitats. The California flora offers a well‐characterized model system to examine whether native and exotic species differ in the distribution of functional traits and to examine whether a breakdown of the CC tradeoff is present. We used a random subset of 1000 plants and examined seed traits and life form characteristics along with their seed size and adult height using the Jepson Manual of the plants of California. To test the hypothesis that active dispersal strategies aid in the success of exotic species, we classified species into four seed types according to the presence/absence of mechanisms associated with efficient dispersal. In addition, for each species we compiled data on seed size and adult plant height. We conducted all comparisons between native and exotic species within the four most speciose families to control for potential taxonomic non‐independence. Exotic species had smaller seed size but greater plant height than natives of the same families. On the other hand, exotic species also displayed significantly greater proportions of functional traits that enhanced dispersal ability. Additionally, certain sets of functional traits were significantly associated with exotic species, such as annual life histories with small seeds and high dispersal capacity. In the random subset of the California flora examined, exotics of the most speciose plant families show functional trait combinations that appear to violate the tradeoff structures observed in their California counterparts. Our results suggest that taxonomically controlled comparisons of the CC tradeoff structure between natives and exotic species may shed light of the capacity of those exotic species invasive ability to colonize new habitats.
Are Phosphodiesterase Type 5 Inhibitors Associated with Vision-Threatening Adverse Events? A Critical Analysis and Review of the Literature
Authors: Azzouni F. , Abu samra K.
Published: July 2011

Introduction

Phosphodiesterase type 5 (PDE5) inhibitors are the first line drugs for treatment of erectile dysfunction. Sildenafil (ViagraR), tadalafil (CialisR), and vardenafil (LevitraR) are from the same class of drugs that inhibit PDE5. Transient visual symptoms such as change in color perception and increased light sensitivity are well-known adverse effects of these drugs and occur in 3–11% of sildenafil users. Vision-threatening (serious) ocular complications, such as nonarteritic ischemic optic neuropathy and cilio-retinal artery occlusion have rarely been reported in PDE5 inhibitor users.

Aims

To highlight and analyze the most recently published case literature on serious ocular complications of PDE5 inhibitors.

Methods

Search of the peer-reviewed English literature was conducted using Medline. The following databases also were searched: Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, Global Health, and MD Consult. The causality assessment of the reported adverse drug reactions was analyzed by applying both the World Health Organization (WHO) Probability Scale and the criteria utilized by the National Registry of Drug-Induced Ocular Side Effects.

Main Outcome Measures

To scientifically and objectively find out if PDE5 inhibitors are associated with vision-threatening ocular complications.

Results

Eight case reports of serious PDE5 inhibitor-associated ocular complications were identified since January 2006 until February 2011. Case reports included cases of anterior and posterior nonarteritic ischemic optic neuropathy, central retinal vein occlusion, cilio-retinal artery occlusion, acute angle closure glaucoma and optic atrophy after sildenafil use.

Conclusion

There is lack of conclusive evidence to indicate a direct cause–effect relationship between PDE5 inhibitor use and vision-threatening ocular events. Men who use PDE5 inhibitors appear to suffer vision-threatening complications at the same frequency as the general population. However, minor visual adverse effects occur in 3–11% of users and they are transient and reversible.
Practical Issues of Physiologic Measurement for Clinical Research with Children. Part I: Measurement Accuracy and Precision
Authors: Thorngate Lauren , Foreman Shuyuann Wang
Published: July 2011

Column Editor: Lauren Clark

Scientific Inquiry provides a forum to facilitate the ongoing process of questioning and evaluating practice, presents informed practice based on available data, and innovates new practices through research and experimental learning.
Bench‐Scaled Nano‐Fe0 Permeable Reactive Barrier for Nitrate Removal
Authors: Hosseini S. Mossa , Ataie‐Ashtiani B. , Kholghi M.
Published: July 2011

There are many fundamental problems with the injection of nano‐zero‐valent iron (NZVI) particles to create permeable reactive barrier (PRB) treatment zone. Among them the loss of medium porosity or pore blocking over time can be considered which leads to reduction of permeability and bypass of the flow and contaminant plume up‐gradient of the PRB. Present study provides a solution for such problems by confining the target zone for injection to the gate in a funnel‐and‐gate configuration. A laboratory‐scale experimental setup is used in this work. In the designed PRB gate, no additional material from porous media exists. NZVI (d50 = 52 ± 5 nm) particles are synthesized in water mixed with ethanol solvent system. A steady‐state condition is considered for the design of PRB size based on the concept of required contact time to obtain optimum width of PRB gate. Batch experiment is carried out and the results are used in the design of PRB gate width (~50 mm). Effect of high initial NO3–‐N concentration, NZVI concentration, and pore velocity of water in the range of laminar groundwater flow through porous media are evaluated on nitrate‐N reduction in PRB system. Results of PRB indicate that increasing the initial NO3–‐N concentration and pore velocity has inhibitor effect—against the effect of NZVI concentration—on the process of NO3–‐N removal. Settlement velocity (S.V.) of injected NZVI with different concentrations in the PRB is also investigated. Results indicate that the proposed PRB can solve the low permeability of medium in down‐gradient but increasing of the S.V. especially at higher concentration is one of the problems with this system that needs further investigations.
A private‐sector, incentives‐based model for justice reinvestment
Authors: Clear Todd R.
Published: July 2011

Research Summary

Justice reinvestment is a recent strategy designed to reduce the use of incarceration and divert the savings to improve the circumstances of communities that have high incarceration rates. More than a dozen states have mounted justice reinvestment projects. While support for justice reinvestment remains high, actual results have been mixed. In particular, the “community reinvestment” aspect of justice reinvestment has been disappointing. An approach that focuses on the private sector and creates incentives for private justice reinvestment could resolve some of these current limitations of the method.

Policy Summary

Advocates for justice reinvestment would be able to address some of the problems in the approach by developing financial incentives that involve the private sector in justice reinvestment activity.
Larval descriptions of five Byctiscus species (Coleoptera: Rhynchitidae) in Korea
Authors: PARK Jinyoung , LEE Jong Eun , PARK Jong Kyun
Published: July 2011

The genus Byctiscus reported in Korea in five of nine species (B. lacunipennis, B. rugosus, B. puberulus puberulus, B. princeps and B. coerulans) is described for the last instar larvae. In addition, the cradle structure and host‐plants are provided.
Institutionalizing fairness in financial markets: Mission impossible?
Authors: Gilad Sharon
Published: July 2011

This article analyzes the institutionalization of process‐oriented regulation, namely: regulatory institutions that allow firms to adapt regulation to their individual circumstances, while holding them to account for the adequacy and efficacy of their internal compliance systems. The article's main focus is on the strategies sought by compliance professionals to attain managers' receptiveness to regulatory expectations. It analyzes British financial firms' responses to a process‐oriented regulatory initiative, which sought to transform the widespread culture of product “mis‐selling” in this industry. Three key arguments and hypotheses are put forward: first, it is suggested that the existing theoretical literature on process‐oriented regulation overly stresses managers' rational, profit‐maximizing motivations for (non‐)compliance, whilst overlooking their emotive motivations. Second, it is proposed that managers' emotive resistance is expected when regulatory expectations challenge firms' “organizational identities” and thereby their individual identities. Third, it is hypothesized that when process‐oriented regulation poses a threat to organizations' identities, its institutionalization will entail delegation of the design and subsequent implementation of compliance systems to managers outside compliance, and reframing of regulatory expectations into existing businesses discourses and methodologies.
Rapid generation of pandemic influenza virus vaccine candidate strains using synthetic DNA
Authors: Verity Erin E. , Camuglia Sarina , Agius Catherine T. , Ong Chi , Shaw Robert , Barr Ian , Middleton Deborah , Rockman Steven
Published: July 2011

Please cite this paper as: Verity et al. (2011) Rapid generation of pandemic influenza virus vaccine candidate strains using synthetic DNA. Influenza and Other Respiratory Viruses DOI:10.1111/j.1750‐2659.2011.00273.x.

Background  Vaccination is considered the most effective means of reducing influenza burden. The emergence of H5N1 and pandemic spread of novel H1N1/2009 viruses reinforces the need to have strategies in place to rapidly develop seed viruses for vaccine manufacture.

Methods  Candidate pandemic vaccine strains consisting of the circulating strain haemagglutinin (HA) and neuraminidase (NA) in an A/PR/8/34 backbone were generated using alternative synthetic DNA approaches, including site‐directed mutagenesis of DNA encoding related virus strains, and rapid generation of virus using synthetic DNA cloned into plasmid vectors.

Results  Firstly, synthetic A/Bar Headed Goose/Qinghai/1A/2005 (H5N1) virus was generated from an A/Vietnam/1194/2004 template using site‐directed mutagenesis. Secondly, A/Whooper Swan/Mongolia/244/2005 (H5N1) and A/California/04/09 (H1N1) viruses were generated using synthetic DNA encoding the viral HA and NA genes. Replication and antigenicity of the synthetic viruses were comparable to that of the corresponding non‐synthetic viruses.

Conclusions  In the event of an influenza pandemic, the use of these approaches may significantly reduce the time required to generate and distribute the vaccine seed virus and vaccine manufacture. These approaches also offer the advantage of not needing to handle wild‐type virus, potentially diminishing biocontainment requirements.
Immunological Detection of N‐formylkynurenine in Porphyrin‐Mediated Photooxided Lens α‐crystallin
Authors: Ehrenshaft Marilyn , Zhao Baozhong , Andley Usha P. , Mason Ronald P. , Roberts Joan E.
Published: July 2011

Crystallin proteins are responsible for maintaining lens transparency and allowing the lens to focus light undistorted onto the retina. The α‐crystallins are the major lens crystallins, and function as both structural proteins and chaperones to protect all lens proteins from damage leading to lens deterioration. Because lens crystallin proteins do not turn over, the damage they accumulate can lead to cataracts, the world’s leading cause of blindness. Photosensitizing porphyrins can accumulate in the eye through either endogenous metabolism or through therapeutic or diagnostic procedures. Porphyrin buildup exacerbates lens aging through increased levels of singlet oxygen, resulting in protein polymerization and amino acid residue alteration. Tryptophans oxidize to kynurenine and N‐formylkynurenine (NFK) causing irreversible changes in the refractive index of the normally transparent lens, leading to development of cataracts. Additionally, NFK is itself a photosensitizer, and its presence exacerbates lens deterioration. This work uses anti‐NFK antiserum to study porphyrin‐facilitated photooxidation of α‐crystallin tryptophan residues. In vitro experiments show that four biologically interesting porphyrins mediate α‐crystallin polymerization and accumulation of both protein radicals and NFK. Confocal microscopy of cultured human lens epithelial cells indicates that while all four porphyrins photosensitize cellular proteins, not all oxidize the tryptophans of cellular α‐crystallin to NFK.
Should we have concerns with generic versus brand antimicrobial drugs? A review of issues
Authors: Veronin Michael A
Published: July 2011

Objectives

To explore the issues involving generic versus brand antimicrobial drug products and provide an overview of assessments of equivalence and their potential relevance to health outcomes.

Methods

In April and May 2010, literature searches were performed in MEDLINE and EMBASE for studies involving antimicrobial drug products that convey equivalence or non-equivalence of generic and brand-name drugs.

Key findings

Sixty-six studies involving antibiotics, antifungals, antivirals and antimalarials were identified for analysis. The types of studies were categorized into microbial assays, pharmaceutical assays, bioequivalence and those that assess clinical endpoints. Studies varied markedly on equivalence measures between generic and brand drug products. Thirty-four of 66 (52%) were primarily bioequivalency studies with 30 of 34 (88%) demonstrating positive outcomes for equivalency. Two of 22 studies (9%) involved microbial and/or pharmaceutical assays for quality assurance testing and presented the largest disparity in equivalence. Ten studies compared outcomes of a clinical nature and concluded no significant difference in outcome between generic and brand products. Ten of 66 (15%) studies were published before 2000 and 11 (17%) were conducted in the USA.

Conclusions

In the USA, it is unlikely that use of generic antibiotics and antimicrobials pose a problem for patients with infectious diseases, where quality safeguards exist and patients are informed when generic substitution occurs. However, with expansion of international markets and questionable drug supply chains – particularly with the advent of the internet – consumers and providers should be aware of drug product quality differences that may impact patient outcomes.
Where a cheap medicine is not the same as a generic medicine: the Belgian case
Authors: Dylst Pieter , Vulto Arnold , Simoens Steven
Published: July 2011

Objectives

The aim of this article is to describe the experience with the Belgian policy that obliges physicians to prescribe minimum quota of cheap medicines and to document the outcomes of this policy using publicly available data.

Methods

Data were obtained from yearly feedback reports of the policy on the website of the Belgian third-party payer (RIZIV/INAMI), which were sent to all physicians. Data were derived from Farmanet, a database where all data of prescriptions of reimbursed medicines from all physicians in Belgium are collected.

Key findings

All groups of general practitioners, specialists and dentists reached their minimum percentages every year from 2006 until 2009. The percentage of cheap medicines (in defined daily doses) increased from 22.9% in January 2005 to 44.2% of all prescribed medicines in ambulatory care in December 2009. The percentage of generic medicines increased from 12.10% in 2004 to 24.03% of all prescribed medicines in ambulatory care in 2008. When a physician prescribed a cheap medicine, this was an original medicine whose price had dropped to the reference price level in 41.5% of cases in August 2009.

Conclusions

The policy of prescribing quota for cheap medicines was not only associated with increased prescribing of generic medicines during 2004–2008, but also increased prescribing of original medicines whose price had dropped to the reference price level. The potential for prescribing generic medicines has not yet been fully met in Belgium. Despite the success of the policy, adjustments are desirable, especially with respect to the broad definition of cheap medicines. Given the fact that all groups of physicians reached their minimum quota quite easily together with the increased possibility of prescribing cheap medicines due to the entrance of new, generic medicines, the government decided to raise the minimum criteria in 2011.
Polymicrobial periodontal pathogen transcriptomes in calvarial bone and soft tissue
Authors: Bakthavatchalu V. , Meka A. , Mans J.J. , Sathishkumar S. , Lopez M.C. , Bhattacharyya I. , Boyce B.F. , Baker H.V. , Lamont R.J. , Ebersole J.L. , Kesavalu L.
Published: July 2011

Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia are consistently associated with adult periodontitis. This study sought to document the host transcriptome to a P. gingivalis, T. denticola, and T.forsythia challenge as a polymicrobial infection using a murine calvarial model of acute inflammation and bone resorption. Mice were infected with P. gingivalis, T. denticola, and T. forsythia over the calvaria, after which the soft tissues and calvarial bones were excised. A Murine GeneChip® array analysis of transcript profiles showed that 6997 genes were differentially expressed in calvarial bones (P < 0.05) and 1544 genes were differentially transcribed in the inflamed tissues after the polymicrobial infection. Of these genes, 4476 and 1035 genes in the infected bone and tissues were differentially expressed by upregulation. Biological pathways significantly impacted by the polymicrobial infection in calvarial bone included leukocyte transendothelial migration (LTM), cell adhesion molecules, adherens junction, major histocompatibility complex antigen, extracellular matrix–receptor interaction, and antigen processing and presentation resulting in inflammatory/cytokine/chemokine transcripts stimulation in bone and soft tissue. Intense inflammation and increased activated osteoclasts were observed in calvarias compared with sham‐infected controls. Quantitative real‐time RT‐PCR analysis confirmed that the mRNA level of selected genes corresponded with the microarray expression. The polymicrobial infection regulated several LTM and extracellular membrane pathway genes in a manner distinct from mono‐infection with P. gingivalis, T. denticola, or T. forsythia. To our knowledge, this is the first definition of the polymicrobially induced transcriptome in calvarial bone and soft tissue in response to periodontal pathogens.
Predicting alcohol consumption and binge drinking in company employees: An application of planned behaviour and self‐determination theories
Authors: Hagger Martin S. , Lonsdale Adam J. , Hein Vello , Koka Andre , Lintunen Taru , Pasi Heidi , Lindwall Magnus , Rudolfsson Lisa , Chatzisarantis Nikos L. D.
Published: July 2011

Objectives.  This study tested an integrated model of the psychosocial determinants of alcohol‐related behaviour among company employees from four nations. A motivational sequence was proposed in which motivational orientations from self‐determination theory influenced intentions to consume alcohol within guideline limits and alcohol‐related behaviour via the mediation of the theory of planned behaviour variables of attitude, subjective norms, and perceived behavioural control (PBC).

Design.  A three‐wave prospective design using self‐reported psychological and behavioural measures.

Methods.  Company employees (N= 486, males = 225, females = 261; M age = 30.41, SD= 8.31) from four nations (Estonia, Finland, Sweden, and UK) completed measures of autonomous and controlled motivation from self‐determination theory, attitudes, subjective norms, PBC, intentions from the theory of planned behaviour, and self‐reported measures of past alcohol consumption and binge‐drinking occasions at the first time point (time 1). Follow‐up psychological and behavioural measures were taken one month later (time 2) and follow‐up behavioural measures taken a further 2 months later (time 3).

Results.  Path analyses supported the motivational sequence with identified regulation (time 1), predicting intentions (time 1), and alcohol units consumed (time 2). The effects were indirect via the mediation of attitudes and PBC (time 1). A similar pattern of effects was found for the effect of time 2 psychological variables on time 3 units of alcohol consumed. There was little support for the effects of the psychological variables on binge‐drinking behaviour.

Conclusions.  Findings provide new information on the psychosocial determinants of alcohol behaviour in company employees and the processes involved. Results may provide impetus for the development of interventions to reduce alcohol consumption.
Rapid and reversible formation of spine head filopodia in response to muscarinic receptor activation in CA1 pyramidal cells
Authors: Schätzle Philipp , Ster Jeanne , Verbich David , McKinney R. Anne , Gerber Urs , Sonderegger Peter , María Mateos José
Published: July 2011

Non‐technical summary  Changes in the shape and number of spines on neuronal dendrites modify synaptic transmission and circuit properties, processes considered important for learning and memory. We show, in hippocampal pyramidal neurons, that brief activation of acetylcholine receptors of the muscarinic subtype induces the emergence of fine filopodia from spine heads in all CA1 pyramidal neurons examined. Experiments to test whether changes in the cytoskeleton play a role in the emergence of filopodia revealed that the extension of microtubules, but not actin polymerization, was necessary. These findings reveal a new form of structural plasticity at the subspine level where the heads of mature dendritic spines can modulate the degree of interaction with their presynaptic partners. Knowledge of how the cholinergic system in the brain affects spine morphology and physiology is important for understanding memory formation.
Temporal changes in microvessel leakiness during wound healing discriminated by in vivo fluorescence recovery after photobleaching
Authors: Machado Maria J. C. , Mitchell Christopher A.
Published: July 2011

Non‐Technical Summary  Wound closure depends on vascular ingrowth into the injured area and this process has traditionally been studied in tissue sections of animals ex vivo. Following the creation of a wound within a surgically implanted dorsal window chamber, we captured microscopic images of the ingrowing vasculature on successive days after injury. Using a combination of surgical, confocal microscopic and mathematical techniques we quantified the flux of plasma into and around vessels including: newly formed vessel sprouts, nascent flowing vascular segments and pre‐existing vessels within the same wound. From these analyses we are able to discriminate: (1) vessels with differing maturity, (2) that vascular sprouts get progressively less leaky and (3) TNP‐470 (an anti‐angiogenic agent), reduces leakiness in sprouts with co‐incident secondary effects on pre‐existing vessels. These techniques can be used to assess both functional maturity and the effects of therapeutics on the vasculature of healing wounds.