bluuebunny/crossref_metadata_2025 huggingface dataset:
Lower Risk of Revision With Patellar Tendon Autografts Compared With Hamstring Autografts
Authors: Gifstad Tone , Foss Olav A. , Engebretsen Lars , Lind Martin , Forssblad Magnus , Albrektsen Grethe , Drogset Jon Olav
Published: September 2014

Background:

A number of studies have found comparable results after anterior cruciate ligament (ACL) reconstruction with patellar tendon autografts and hamstring autografts; however, few studies have been large enough to reveal differences in risk of revision with regard to clinical and demographic factors.

Purpose:

To present the distribution of grafts for ACL reconstruction based on data in the Scandinavian ACL registries and to compare the risk of revision between patellar tendon autografts and hamstring autografts. Potential associations with other clinical and demographic factors were also explored.

Study design:

Cohort study; Level of evidence, 2.

Methods:

A total of 45,998 primary ACL reconstructions, including 6736 patellar tendon autografts and 38,666 hamstring autografts, were identified in the Scandinavian ACL registries. The overall median follow-up time was 3 years (range, 0-8 years). To compare the risk of revision between groups of patients, univariate Kaplan-Meier analysis (with log-rank test) and the Cox proportional hazard regression model were applied. The hazard rate ratio with 95% CI was reported as a measure of effect.

Results:

Patellar tendon and hamstring autografts were used in 14.6% and 84.1% of the patients, respectively. The remaining patients received allografts, direct sutures, or other graft types (1.3%). The primary ACL injury occurred during soccer, team handball, or alpine activities in 67.5% of the patients in the patellar tendon group and 66.2% in the hamstring group. A total of 156 patients in the patellar tendon group and 1042 patients in the hamstring group underwent revision. The overall risk of revision was significantly lower in the patellar tendon group versus the hamstring group (hazard rate ratio = 0.63; 95% CI, 0.53-0.74), and it decreased with increasing age at surgery, although not strictly linearly. The lower risk of revision in the patellar tendon group was consistently observed across subgroups of patient sex, age, and concomitant cartilage injury ( P > .05, test for interaction) but seemed to be slightly more pronounced for patients injured during certain pivoting activities (soccer, team handball, and alpine activities) compared with other activities (hazard rate ratio = 0.57 vs 0.81; P = .058, test for interaction).

Conclusion:

The majority of primary ACL reconstructions in Scandinavia are performed with hamstring autografts. Results from the present large prospective study show that patients receiving patellar tendon autografts have a statistically significantly lower risk of revision compared with patients receiving hamstring autografts.
Luc Boltanski and democratic theory
Authors: Blokker Paul
Published: September 2014

In Luc Boltanski’s On Critique, various dimensions of democracy as a political regime and form of society are evident, but never explicitly conceptualized. There is, however, something to be gained by making the democratic dimension in Boltanski’s work more explicit: the normative and political standpoints become clearer, but also the real-life possibilities for and significance of critique in contemporary times. The paper will first discuss the (latent) democratic theory in On Critique by focusing on the differentiation between reality and the world and the conceptualization of institutions. In a second step, I will relate a rather rudimentary democratic theory to the radical-democratic dimensions of the work of Claude Lefort and Cornelius Castoriadis in order to make its contours more explicit. In a third step, I will discuss a tension that exists between the radical-democratic dimension in On Critique and Boltanski’s portrayal of contemporary capitalist-democratic societies as largely immune to critique.
The enigma of capitalism and the French cul-de-sac
Authors: Murphy Peter
Published: September 2014

The article is an evaluation of the economic, organizational and social theory of Luc Boltanski and Eve Chiapello’s The New Spirit of Capitalism 15 years after its publication. The role of network capitalism, state capitalism, and aesthetic capitalism in French social life is analysed. The article concludes that flexible network capitalism was largely a chimera of the 1990s and that French political and economic life today is dominated by an ailing state capitalism.
Effect of molding condition on flexural strength of textile carbon fiber reinforced polycarbonate laminates
Authors: Ozaki Hiroaki , Nakada Masayuki , Uzawa Kiyoshi , Miyano Yasushi
Published: September 2014

The effects of molding conditions on the flexural strength of textile carbon fiber reinforced polycarbonate laminates were assessed. Choosing the temperature and pressure conditions appropriately during hot-press molding using carbon fiber textile layers and polycarbonate films can produce void-free, high interfacial adhesion in textile carbon fiber reinforced polycarbonate laminates. Those characteristics were confirmed from observing the cross-sections of carbon fiber reinforced polycarbonate laminates and measuring the interlaminar shear strength. A suitable molding condition can raise the flexural strength of carbon fiber reinforced polycarbonate laminates to a level predicted from the measured flexural strength of textile carbon fiber/epoxy laminates by assuming carbon fiber micro-buckling in the compression side of specimens.
Glycosaminoglycans and their sulfate derivatives differentially regulate the viability and gene expression of osteocyte-like cell lines
Authors: Tsourdi Elena , Salbach-Hirsch Juliane , Rauner Martina , Rachner Tilman D , Möller Stephanie , Schnabelrauch Matthias , Scharnweber Dieter , Hofbauer Lorenz C
Published: September 2014

Collagen and glycosaminoglycans, such as hyaluronan and chondroitin sulfate, are the major components of bone extracellular matrix, and extracellular matrix composites are being evaluated for a wide range of clinical applications. The molecular and cellular effects of native and sulfate-modified glycosaminoglycans on osteocytes were investigated as critical regulators of bone remodeling. The effects of glycosaminoglycans on viability, necrosis, apoptosis, and regulation of gene expression were tested in two osteocyte-like cell lines, the murine MLO-Y4 and the rat UMR 106-01 cells. Glycosaminoglycans were non-toxic and incorporated by osteocytic cells. In MLO-Y4 cells, sulfation of glycosaminoglycans led to a significant inhibition of osteocyte apoptosis, 42% inhibition for highly sulfated chondroitin sulfate and 58% for highly sulfated hyaluronan, respectively. Cell proliferation was not affected. While treatment with highly sulfated chondroitin sulfate increased cell viability by 20% compared to the native chondroitin sulfate. In UMR 106-01 cells, treatment with highly sulfated hyaluronan reduced the receptor activator of nuclear factor-κB ligand/osteoprotegerin ratio by 58% compared to the non-sulfated form, whereas highly sulfated chondroitin sulfate led to 60% reduction in the receptor activator of nuclear factor-κB ligand/osteoprotegerin ratio in comparison to the native chondroitin sulfate. The expression of SOST, the gene encoding sclerostin, was reduced by 50% and 45% by highly sulfated hyaluronan and chondroitin sulfate, respectively, compared to their native forms. The expression of BMP-2, a marker of osteoblast differentiation, was doubled after treatment with the highly sulfated hyaluronan in comparison to its native form. In conclusion, highly sulfated glycosaminoglycans inhibit osteocyte apoptosis in vitro and promote an osteoblast-supporting gene expression profile.
Not All Crime Policies Are Created Equal
Authors: Oliver Willard M. , Marion Nancy E. , Hill Joshua B.
Published: September 2014

Previous research suggests that American presidents resort to the use of symbolic rhetoric because of public opinion, party affiliation, election year politics, and divided government. This research, however, treated crime policy as a general topic, disregarding the nuances that emerge from different types of crime policies. The research at hand posits not all crime policies are the same or handled the same politically, and thus divides them into seven crime policy categories: law enforcement, courts, corrections, juveniles, guns, death penalty, and drugs. Drawing upon the theory of symbolic rhetoric and categorizing presidential speeches from 1948 through 2010 into these seven categories, this study employs logistic regression to explain the influencing variables upon the likelihood presidents will employ symbolic rhetoric for each of these crime policy types. Findings suggest that although the use of symbolic rhetoric is different for each crime policy issue, there are two key factors that matter overall: divided government and party affiliation.
A Qualitative Exploration of the STEM Career-Related Outcome Expectations of Young Adolescents
Authors: Shoffner Marie F. , Newsome Debbie , Barrio Minton Casey A. , Wachter Morris Carrie A.
Published: September 2014

Perceptions developed and choices made during the preadolescent and early adolescent years may restrict or enrich youth’s future career aspirations. These years are critical for acquiring and exploring academic and career-related interests. In addition, outcome expectations – what youth believe will happen if they pursue certain interests, tasks, or goals – are important predictors of eventual career choice. With national, state, and local initiatives advocating science, technology, engineering, and mathematics (STEM) knowledge and career goals, there is a need to understand youth’s outcome expectations regarding these fields. We present a qualitative study examining the outcome expectations of 95 youth aged 10–14, using focus group data. Several of the identified outcome expectations had negative connotations. Results supported the outcome expectations identified by Bandura (i.e., physical, social, and self), and two additional types of outcome expectations (generativity and relational). These two outcome expectations have special relevance for the underrepresentation of girls, women, and minorities in STEM occupations.
Competing Values Framework Application to Organizational Effectiveness in Voluntary Organizations
Authors: Grabowski Louis , Neher Cathy , Crim Timothy , Mathiassen Lars
Published: September 2014

Although the widely used Competing Values Framework (CVF) has attracted considerable attention in the literature and has proven useful as an approach to organizational effectiveness, we know little about how it applies to voluntary organizations. We therefore combined CVF with rigorous action research methodology to analyze the organizational effectiveness of Right in the Community (RitC), a voluntary agency serving the developmentally disabled. As our results show, CVF’s three dimensions of organizational focus, structural preference, and managerial concern helped us improve the organization’s management of scarce resources, organizational structure and governance, and innovative capabilities. During the collaboration, we also observed tensions between heart and head that were particularly relevant for improving organizational effectiveness at RitC. We therefore propose extending CVF for voluntary organizations with a fourth dimension: motivational trait.
Comprehensive kinematic modeling and analysis of a coaxial helicopter’s swashplate mechanism
Authors: Yuan Xiaming , Zhu Jihong , Chen Zhigang , Lu Xingju , Meng Jiadong
Published: September 2014

A comprehensive mathematical model of a coaxial helicopter’s swashplate mechanism is established, analyzed and verified in this paper. The mechanism widely used in helicopters to manipulate blade pitch angles is complex because of its configuration of multi closed-loop kinematic chains, especially for coaxial layout. First, geometrical method is used in determining the direct and inverse position kinematics. Based on that model, an approach of differentiation on spatial vectors is adopted to induce the relative velocity and acceleration matrices of every part of the system. The influence of rotors’ rotation is also considered in the modeling of velocity and acceleration kinematics to obtain a comprehensive model. The workspace and dexterity characteristics are analyzed in detail under the constraint of actuators’ inputs. After that, the complete direct kinematic model is simulated with consideration of control allocation and actuator dynamics. Finally, an integrated verification approach is designed based on experimental and simulative method to validate the established model. The work is concluded with an application prospect in future.
Numerical and experimental analysis of microchannel heat transfer for nanoliquid coolant using different shapes and geometries
Authors: Garg Harry , Negi Vipender Singh , Garg Nidhi , Lall AK
Published: September 2014

As part of the liquid cooling, most of the work has been done on fluid flow and heat transfer analysis for flow field. In the present work, the experimental and numerical studies of the microchannel the fluid flow and heat transfer analysis using nanoliquid coolant have been discussed. The practical aspects for increasing the high heat transfer coefficient from conventional studies and the different geometries and shapes of the microchannel are studied. The Aspect Ratio has significant effect on the microchannels and has been varied from AR 2, 4 and 8 to choose the optimum one. Three different fluids, i.e. de-ionized water, ethylene glycol, and a custom nanofluid are chosen for study. The proposed nanofluid almost interacts as another solid and has reduced thermal resistance, friction effect, and thus it almost vanishes high hot spots. Experimental analysis shows that the proposed nanofluid is excellent fluid for high rate heat removals. Moreover, the performance of the overall system is excellent in terms of high heat transfer coefficient, high thermal conductivity, and high capacity of the fluid. It has been reported that the heat transfer coefficient can be increased to 2.5 times of the water or any other fluid. It was also reported that the AR 4 rectangular-shaped channels are the optimum geometry in the Reynolds number ranging from 50 to 800 considering laminar flow. Examination and identification is based upon the practical result that includes fabrication constraints, commercial application, sealing of the system, ease of operation, and so on.
Mutually converted arc–line segment-based SLAM with summing parameters
Authors: Yan Rui-Jun , Wu Jing , Shao Ming-Lei , Shin Kyoo-Sik , Lee Ji-Yeong , Han Chang-Soo
Published: September 2014

This paper presents a mutually converted arc–line segment-based simultaneous localization and mapping (SLAM) algorithm by distinguishing what we call the summing parameters from other types. These redefined parameters are a combination of the coordinate values of the measuring points. Unlike most traditional features-based simultaneous localization and mapping algorithms that only update the same type of features with a covariance matrix, our algorithm can match and update different types of features, such as the arc and line. For each separated data set from every new scan, the necessary information of the measured points is stored by the small constant number of the summing parameters. The arc and line segments are extracted according to the different limit values but based on the same parameters, from which their covariance matrix can also be computed. If one stored segment matches a new extracted segment successfully, two segments can be merged as one whether the features are the same type or not. The mergence is achieved by only summing the corresponding summing parameters of the two segments. Three simultaneous localization and mapping experiments in three different indoor environments were done to demonstrate the robustness, accuracy, and effectiveness of the proposed method. The data set of the Massachusetts Institute Of Technology (MIT) Computer Science and Artificial Intelligence Laboratory (CSAIL) Building was used to validate that our method has good adaptability.
A methodology for predicting solar power incidence on airfoils and their optimization for solar-powered airplanes
Authors: Marques Hobold Gustavo , Agarwal Ramesh K
Published: September 2014

In recent years, there has been great deal of interest in exploration of alternative fuels other than jet fuel for aircraft propulsion in order to reduce the greenhouse gas emissions. For commercial transport as well as military aircraft, there has been a great deal of emphasis on “biofuels”, which behave like “drop-in fuel” but generate less CO2 and NOx emissions and, therefore, are more environmentally friendly. However, for small unmanned air vehicle or low-speed personal transportation aircraft, there have been many attempts towards building an all-electric or solar airplane whose wings could possibly be covered with photovoltaic panels to harness sun’s energy for propulsion. Most notably, the success of “solar impulse” has attracted the attention of general public as well as small aircraft enthusiasts. The focus of this paper is on the airfoil/wing design for optimal utilization of solar energy for powering a solar airplane. We analyze the incidence of solar radiation over an airfoil/wing of an airplane. We show that, under some conditions, the incidence is independent of the shape of the airfoil. We develop a more complete model to compute the total solar radiation incident on the airfoil during a cruise flight using the solar tracking equations and geodesy for path creation. The model is based on discretization of both the airfoil and the path. To illustrate the versatility of the model, we employ a genetic algorithm with migration to optimize the airfoil shape during some specific given flight conditions and discuss the results.
Mathematical modeling of transpiration cooling in cylindrical domain
Authors: Aybar Hikmet Ş , Faridani Mehdi M
Published: September 2014

This research reports on the development of a mathematical modeling to simulate the transpiration cooling in a rocket thrust chamber. The transpiration cooling is a process used to protect the thrust chamber wall of a liquid rocket engine so that the coolant can mitigate the large amount of heat transfer by getting preheated prior to entering the thrust chamber. The mathematical model for the porous layer is developed in cylindrical coordinate system, and the results are validated by the experimental results available in open literature. Also, a numerical method is developed to solve the equations of hot gases which are flowing through the nozzle in order to provide the hot boundary condition of the porous layer. The flow equations within the porous medium are solved separately to analyze the important parameters affecting the transpiration cooling process. A parametric study is performed to investigate the effect of coolant mass flow rate, hot face boundary condition, gas type, and porous layer thickness. Moreover, the internal convective heat transfer between solid structure and the coolant flow is studied. The porous solver code is then coupled with the gas solver code to examine the cooling process more realistically. The results show the variation of gas properties through the nozzle and the effect of transpiration cooling on them. The paper concludes with a demonstration of a sample method of controlling the nozzle wall temperature.
Shock loss model and blade profile optimization design of a supersonic cascade
Authors: Sun Xiaolei , Yang Shihao , Zhao Qingjun
Published: September 2014

With the improvement of single-stage compressor load, the inflow velocity and relative Mach number at blade tip of compressor are further increased. Using supersonic blade profile to design highly loaded compressor is an effective method to satisfy the requirements of the compressor aerodynamic design. In the internal flow of a blade row, detached shock is caused at the leading edge of supersonic cascade, and complex passage shock structure is produced by shock and boundary layer interaction at blade surface. Establishing shock loss calculation method for detached shock and passage shock and optimizing the blade profile according to the shock loss mechanisms are effective means to design high-efficiency compressors. The earlier studies of shock loss calculation model in supersonic compressor cascade have shown that shock loss of the detached shock at leading edge is related to leading edge radius and inlet Mach number. Therefore, several shock loss models for detached shock are established and proved to be effective. In previous studies on passage shock loss, the changes in geometry of passage shock, which is caused by shock and boundary layer interaction, are not fully considered. So, it is necessary to do further study on passage shock loss model. Based on the internal flow characteristics in supersonic cascade, passage shock loss model is proposed. Physics-based passage shock geometry, which is determined by static pressure rise, Mach number before wave fronts and blade profile curvature, is applied for this passage shock loss model. Near the blade surface, passage shock geometry is transformed into lambda-type shock that is composed of two branch oblique shocks, and oblique shock relationships are used to calculate their total pressure losses. Away from the blade surface, passage shock geometry is very close to the normal shock shape, so that normal shock relationships are used for loss calculation.
Genotoxicity effect, antioxidant and biomechanical correlation: Experimental study of agarose–chitosan bone graft substitute in New Zealand white rabbit model
Authors: Jebahi Samira , Saleh Ghada Ben , Saoudi Mongi , Besaleh Salma , Oudadesse Hassane , Mhadbi Moufida , Rebai Tarek , Keskes Hassib , Feki Abdelfattah El
Published: September 2014

Bone loss associated with skeletal trauma or metabolic diseases often requires bone grafting. In such situations, a biomaterial is necessary for migrated cells to produce new tissue. In this study, agarose–chitosan was implanted in the femoral condyle of New Zealand White rabbits that were divided into three groups: Group I was used as control; Groups II and III were used as implanted tissue with agarose–chitosan and presenting empty defects, respectively. This study evaluated the agarose–chitosan biocompatibility by determining the in vivo genotoxicity, oxidative stress balance that correlated with the hardness mechanical property. Moreover, the histopathological and quantitative elements analyzed by using inductively coupled plasma optical emission spectrometry were determined. After 30 days of implantation, the in vivo analysis of genotoxicity showed that agarose–chitosan did not induce chromosome aberration or micronucleus damage. A significant decrease in thiobarbituric and acid-reactive substance was observed after agarose–chitosan implantation in the bone tissue. Superoxide dismutase, catalase and glutathione peroxidase were significantly enhanced in agarose–chitosan–treated group compared with that of control group. A negative correlation coefficient of the mechanical property with malonyldialdehyde level was detected (R = −0.998). The histological study exhibited a significantly increased angiogenesis and newly formed tissue. No presence of inflammatory process, necrotic or fibrous tissue was detected. Major and trace elements such as Ca, P, Zn, Mg and Fe were increased significantly in the newly formed bone. These findings show that agarose–chitosan biomaterial implantation might be effective for treating trauma and bone regeneration.
The use of rapid prototyped implants to simulate knee joint abnormalities for in vitro testing: A validation study with replica implants of the native trochlea
Authors: Van Haver Annemieke , De Roo Karel , De Beule Matthieu , Van Cauter Sofie , Labey Luc , De Baets Patrick , Claessens Tom , Verdonk Peter
Published: September 2014

To investigate the biomechanical effect of skeletal knee joint abnormalities, the authors propose to implant pathologically shaped rapid prototyped implants in cadaver knee specimens. This new method was validated by replacing the native trochlea by a replica implant on four cadaver knees with the aid of cadaver-specific guiding instruments. The accuracy of the guiding instruments was assessed by measuring the rotational errors of the cutting planes (on average 3.01° in extension and 1.18° in external/internal rotation). During a squat and open chain simulation, the patella showed small differences in its articulation with the native trochlea and the replica trochlea, which could partially be explained by the rotational errors of the implants. This study concludes that this method is valid to investigate the effect of knee joint abnormalities with a replica implant as a control condition to account for the influence of material properties and rotational errors of the implant.
Hemodynamic simulation of blood flow in a new type of cardiac assist device named AVICENA
Authors: Alizadeh Mansour , Tehrani Pedram , Rahmani Shahrokh
Published: September 2014

The purpose of this study is to investigate the hemodynamic parameters of blood flow in a balloon as a part of a new type of cardiac assist device named AVICENA, which is implanted into the descending aorta to improve the strength of pumping blood flow in a poor-performing left ventricle. Balloon is inflated and deflated during diastole and systole, respectively. The longitudinal velocity of blood flow during balloon inflation and deflation has been considered. Through these investigations, the result reveals that the balloon inflation causes the blood flow to accelerate through the balloon and compensates the blood flow velocity required for the normal circulation system. When the balloon deflates, a reverse flow is generated and improves the perfusion of coronary arteries. Furthermore, the inlet pressure and acting force on the aortic valve for the healthy, unhealthy, and assisted heart have been compared. Result indicates that the force acting on the aortic valve has been considerably reduced for the assisted heart compare to the unhealthy or unassisted heart.
Biomechanical analysis and clinical effects of bridge combined fixation system for femoral fractures
Authors: Wang Da-xing , Xiong Ying , Deng Hong , Jia Fu , Gu Shao , Liu Bai-lian , Li Qun-hui , Pu Qi , Zhang Zhong-zi
Published: September 2014

This work aimed to compare the stress distribution and mechanical properties of our bridge combined fixation system and commonly used metal locking plate screw system by finite element analysis and by using the Zwick/Z100 testing machine. In addition, we also investigated the clinical outcome of our bridge combined fixation system for femoral fractures in 59 patients from June 2005 to January 2013. As a result, the stress distribution in the bone plate and screws of metal locking plate screw system during walking and climbing stairs was significantly lower than that of metal locking plate screw system. No significant difference in the displacement was observed between two systems. The equivalent bending stiffness of bridge combined fixation system was significantly lower than that of metal locking plate screw system. There were no significant differences in the bending strength, yield load, and maximum force between two systems. All the cases were followed up for 12–24 months (average 18 months). The X-ray showed bone callus was formed in most patients after 3 months, and the fracture line was faint and disappeared at 6–9 months postoperatively. No serious complications, such as implant breakage and wound infection, occurred postoperatively. According to self-developed standard for bone healing, clinical outcomes were rated as excellent or good in 55 out of 59 patients (success rate: 93.2%). Therefore, our findings suggest that our bridge combined fixation system may be a promising approach for treatment of long-bone fractures.
Performance impact of impeller blade trimming on centrifugal compressors
Authors: Swain Daniel , Engeda Abraham
Published: September 2014

Centrifugal impeller blade trimming can be used to modify an existing impeller design to meet a new flow or pressure ratio design point. In flow trimming, the passage area is reduced from inlet to outlet along the entire meridional length of the impeller to reduce the flow coefficient of the impeller while maintaining the pressure ratio of the untrimmed impeller. Axial trimming is a method of reducing the blade height at the impeller exit while maintaining the shroud profile of the original impeller in order to reduce the head coefficient of the impeller while maintaining the original flow range. In this work, computational fluid dynamics was employed to numerically model four impellers of varying geometries, speeds, and performance characteristics to study the performance effects and limits of modifying the impeller geometry by either flow or axial trimming. Flow trimming was found to be capable of reducing the flow coefficient by between 20 and 50% while maintaining the pressure ratio and efficiency of the baseline impeller. The suitability of an impeller for flow trimming was found to correlate strongly with flow incidence angle. Reducing the exit blade height of a centrifugal impeller by trimming the blades axially may be used to reduce the pressure ratio of a compressor while maintaining flow range; however, the amount of pressure ratio reduction was limited to between 9 and 13% before choking in the passage reduced the choked flow rate. Impeller performance was found to respond differently to axial trimming based on the diffusion ratio of the baseline impeller.
Observer design for generalized sector-bounded noisy nonlinear systems
Authors: Vijayaraghavan Krishna
Published: September 2014

This article presents a new observer for a class of nonlinear systems, defined as a “generalized sector-bounded” nonlinear system, in the presence of both sensor and input disturbances. The generalized sector-bounded nonlinearity is shown to be a super-set of Lipschitz, bounded Jacobian, one-sided Lipschitz, monotonically increasing and dissipative nonlinearities. This article presents necessary and sufficient conditions for this observer to guarantee a desired minimum performance. The conditions for the observer are presented as a linear matrix inequality that can be solved offline using commercial solvers, and the solution to the linear matrix inequality is used to explicitly compute the observer gain. This article then extends these results to case where an additive nonlinearity appears in the sensor output. The use of the methodology developed in this article is demonstrated through illustrative examples. Compared to previous results on nonlinear observers, the proposed observer guarantees a global performance measure for a very general class of nonlinear systems and does not require online computation of the observer gain.
Pyoderma gangrenosum and systemic lupus erythematosus: a report of five cases and review of the literature
Authors: González-Moreno J , Ruíz-Ruigomez M , Callejas Rubio J L , Ríos Fernández R , Ortego Centeno N
Published: September 2014

Pyoderma gangrenosum (PG) is an uncommon, distinctive cutaneous ulceration which is usually idiopathic, but may be associated with many systemic disorders. The etiopathogenesis of PG is still not well understood. PG is part of the spectrum of the neutrophilic dermatoses and it has been proposed as a prototype of cutaneous autoinflammatory disease. PG usually has a good outcome under immunosuppressive treatment. Although PG has been associated with several systemic diseases, it has rarely been reported in association with systemic lupus erythematosus (SLE). In this article we report five cases of SLE-related PG and review the literature. Our findings support the possible relationship between active SLE and PG, although the mechanism remains unclear. Clinical manifestations, used treatments and outcomes of SLE-related PG do not differ from the described for the general population.
Current office-based hearing screening questions fail to identify adolescents at risk for hearing loss
Authors: Sekhar Deepa L , Zalewski Thomas R , King Tonya S , Paul Ian M
Published: September 2014

Objective

There is a rising prevalence of hearing loss among adolescents in the United States. Current paediatric preventive care recommendations by the Bright Futures guidelines and the American Academy of Pediatrics suggest that clinicians should ask adolescents ten hearing screening questions to identify those who are at high risk of hearing loss for further objective hearing testing. We assessed the utility of these subjective risk assessment questions to distinguish those adolescents with objectively documented hearing loss.

Setting

A single public high school in Pennsylvania.

Methods

We compared results from a prospective study evaluating objective hearing assessments with the use of the ten Bright Futures hearing screening questions plus additional adolescent-specific questions to predict adolescent hearing loss.

Results

In relation to the questions used in this study, adolescents who were referred following objective hearing screens were more likely to report “trouble following the conversation when two or more people are talking at the same time” and a “past experience of slight hearing loss”. Referrals from sound treated booth testing were more likely to report “trouble hearing over the phone” and have a diagnosis or history of hearing loss.

Conclusions

Most Bright Futures questions were not associated with adolescent hearing loss. An objective adolescent hearing screen should be considered in the recommended schedule of preventive care, instead of the current risk-based subjective assessment.
Understanding Women’s Health Promotion and the Rural Church
Authors: Plunkett Robyn , Leipert Beverly , Olson Joanne K. , Ray Susan L.
Published: September 2014

Many rural health resources are linked to community churches, which are often well attended, especially by rural women. We used interpretive phenomenology and the photovoice method to understand how the church influenced health promotion for rural women, whose health is often significantly compromised compared with the health of urban women. Our analysis of the data from individual interviews, group sessions, photographs, and logbooks suggested that the rural church significantly facilitated rural women’s health promotion. The church supported the physical, intellectual, emotional, and spiritual health of rural women, facilitated social connectedness, and provided healthful opportunities to give and to receive. Implications included reframing religious places as health-promoting and socially inclusive places for rural women.
Doing Fence Sitting
Authors: Lofgren Axel , Hewitt Vanessa , das Nair Roshan
Published: September 2014

A growing body of research indicates that the way health care professionals conceptualize mental health might have important clinical implications. We adopted a discursive psychology approach to explore clinical psychologists’ accounts of mental health and its effects. Semistructured interviews were conducted with 11 clinical psychologists in the East Midlands region of the United Kingdom. The participants constructed mental health through building up biological factors and psychosocial aspects as opposite ends of the same spectrum, and then positioned themselves as distant from these extremes to manage issues of stake and accountability. A discourse of moral concern for service users was used to negotiate the implications of having different views of mental health from service users, enabling clinicians to manage issues of accountability and demonstrate their ability to be helpful. This suggests that clinicians should be mindful of the effects of their use of language and make the contingent nature of their knowledge explicit.
Academic Territorial Borders
Authors: Annous Samer , Nicolas Maureen O’Day
Published: September 2014

With the globalization of higher education, English has become the lingua franca of universities operating in non–English-speaking countries seeking internationalization. The communication needs of students studying in such foreign-language contexts have not been fully explored. In this study, the authors interviewed a purposeful sample of professors teaching a variety of specialties in the School of Business in an environment in which English is a foreign language in order to ascertain their perceptions of students’ ability to communicate in English, and these teachers’ ability to focus on their students’ writing skills. The findings reveal that although these teachers asserted the importance of communication skill, particularly in written English, they did not feel that nurturing that skill was part of their academic responsibilities. They felt that they had neither the time nor the expertise to nurture students’ ability to communicate in English.
The Power of Genes
Authors: Cruz Joseph E. , Saksena Rujuta , Jabbour Salma K. , Nosher John L. , Hermes-DeSantis Evelyn , Moss Rebecca A.
Published: September 2014

Objective: To report a case of systemic irinotecan toxicity following regional transarterial chemoembolization with drug-eluting beads loaded with irinotecan (DEBIRI-TACE) in a patient later found to have a homozygous mutation for UGT1A1*28. Case Summary: An 80-year-old woman presented with a cecal colon cancer with synchronous metastases to the liver. After resection of the primary tumor, the patient underwent DEBIRI-TACE with 100 mg of irinotecan to treat the residual disease in the liver. A week after this procedure, the patient developed grade 4 neutropenia, and later, alopecia. Eventually, it was found that the patient had a mutation of UDP glucuronosyltransferase 1 family polypeptide A1 (UGT1A1), which provided a reasonable explanation for the observed reaction. Discussion: The toxic effects of irinotecan are well understood. Patients with genetic polymorphisms of the genes encoding for the enzyme UGT1A1 may have increased incidence of irinotecan-associated toxicities because of decreased clearance of the active metabolite SN38 via the glucuronidation pathway. To date, there have been limited publications describing systemic adverse events following TACE or DEBIRI-TACE and, based on a thorough literature search, none following these procedures in patients with UGT1A1 polymorphisms. Based on the scoring results of the Naranjo algorithm (7), we are confident in attributing the observed reaction to the patient’s genetic polymorphism. Conclusion: Although genetic testing prior to the initiation of irinotecan therapy is not currently recommended, assessment of UGT1A1 polymorphism is warranted when severe adverse events typical of systemic therapy manifest following DEBIRI-TACE.
Recent Evidence for Pharmacological Treatment of Idiopathic Pulmonary Fibrosis
Authors: Covvey Jordan R. , Mancl Erin E.
Published: September 2014

Objective: To describe emerging evidence for the pharmacological treatment of idiopathic pulmonary fibrosis (IPF). Data Sources: A search of PubMed (1966 to July 2014) was performed using the terms idiopathic pulmonary fibrosis and treatment. Study Selection and Data Extraction: Review of articles was restricted to articles in English and relating to placebo-controlled or comparative clinical trial data of recent significance. Evidence statements from the most recent international guidelines and some historical trial data were also included for context. Data Synthesis: Numerous treatment options have been evaluated for IPF. Therapies evaluated in large trials have either resulted in increased mortality (anticoagulation, triple-therapy with N-acetylcysteine [NAC], azathioprine, and prednisone) or demonstrated a lack of efficacy (endothelin receptor antagonists, single-agent NAC). Pirfenidone, a novel antifibrotic and anti-inflammatory agent, has demonstrated efficacy in several recent analyses and is the only approved medication for the treatment of IPF in more than 30 countries outside of the United States, with resubmission to the Food and Drug Administration (FDA) recently made. Nintedanib, a tyrosine kinase inhibitor, has demonstrated encouraging results in phase III studies and has also recently been submitted for FDA approval. Conclusions: Limited options have existed for the treatment of IPF. New evidence suggests that safe and efficacious treatment options for IPF are on the horizon in the form of pirfenidone and nintedanib, although both agents await FDA decisions.
Predictors of a Persistent Dislocation After Reduction of Syndesmotic Injuries Detected With Intraoperative Three-Dimensional Imaging
Authors: Franke Jochen , von Recum Jan , Suda Arnold J. , Vetter Sven , Grützner Paul Alfred , Wendl Klaus
Published: September 2014

Background:

In about 25% of cases, reduction of acute unstable syndesmotic injuries and stabilization with syndesmotic screws leads to an inadequate reduction. Conventional fluoroscopy does not provide reliable information about the reduction outcome. However, use of intraoperative 3D imaging can be more accurate. The purpose of this study was to identify predictors of inadequate reduction so that the need for intra- or postoperative 3D imaging could be assessed. Our hypothesis was that complex injuries of the syndesmosis present a higher risk of malreduction than simpler ankle fractures.

Methods:

From August 2001 to February 2011, 251 unstable syndesmotic injuries were treated from a total of 2286 ankle fractures. In 61 of these cases, malreduction of the fibula into the fibular notch was detected by intraoperative 3D imaging. The influence of all possible concomitant and combination injuries of the ankle joint, surgeon’s experience, and potential implant-related effects was analyzed.

Results:

Thirty-seven Weber C fractures (60.7%), 13 Maisonneuve fractures (21.3%), 10 Weber B fractures (16.4%), and 1 syndesmotic injury without fracture (1.6%) were included. In 14 cases (23%) there was involvement of the posterior malleolus, in 10 cases of the medial malleolus (16.4%), and in 12 cases both (19.7%). The Weber C fractures included 10 bimalleolar fractures with involvement of the posterior malleolus. In neither this combination nor in any other possible injury configuration was it possible to identify a statistically significant correlation with malreduction of the fibula into the fibular notch. The surgeon’s experience or an implant-related effect had no detectable influence either.

Conclusion:

Based on the factors studied, it is not possible to conclude whether a patient has an increased risk of malreduction. Therefore we still recommend verifying all reduction outcomes by intraoperative 3D imaging or postoperative computed tomography.

Level of Evidence:

Level III, retrospective comparative study.
Performance of Total Ankle Arthroplasty and Ankle Arthrodesis on Uneven Surfaces, Stairs, and Inclines
Authors: Jastifer James , Coughlin Michael J. , Hirose Christopher
Published: September 2014

Background:

Both total ankle arthroplasty (TAA) and ankle arthrodesis are options for the treatment of ankle arthritis and have been shown to improve gait postoperatively. Little is known about the postoperative performance of these patients on uneven surfaces.

Methods:

Between 2010 and 2013, 77 consecutive patients were enrolled in a prospective study and completed 12 months of follow-up. Patients received either a TAA (61 patients) or an ankle arthrodesis (16 patients). Preoperatively, at 6 months and 12 months postoperatively, patients were evaluated clinically and functionally on stairs, an inclined ramp, and an uneven surface. Patients graded their function on these surfaces using a visual analog scale (VAS) in addition to standard clinical grading scales.

Results:

There was no statistically significant difference between the patient groups preoperatively (all P > .05). Both TAA and ankle arthrodesis groups had high patient satisfaction, 3.5 and 3.4 out of 4.0, respectively. Both groups had improvement in Buechel-Pappas scores, VAS pain scores, AOFAS Ankle Hindfoot scores, and functional scores (all P values < .05). TAA patients had a significantly better outcome than the arthrodesis patients in the Buechel-Pappas scale ( P = .036), AOFAS Ankle Hindfoot score ( P = .03), ankle dorsiflexion ( P < .001), ankle plantarflexion ( P < .001), walking upstairs ( P = .013), walking downstairs ( P = .012), and walking uphill ( P = .016).

Conclusions:

Patients with TAA and ankle arthrodesis had improved performance walking on uneven surfaces at 12 months of follow-up compared to preoperatively. TAA patients had higher scores than the ankle arthrodesis patients walking upstairs, downstairs, and uphill.

Level of Evidence:

Level II, prospective cohort study.
Inflammatory Cytokines and Cellular Metabolites as Synovial Fluid Biomarkers of Posttraumatic Ankle Arthritis
Authors: Adams Samuel B. , Nettles Dana L. , Jones Lynne C. , Miller Stuart D. , Guyton Gregory P. , Schon Lew C.
Published: September 2014

Background:

There is a paucity of research on posttraumatic ankle arthritis (PTAA). We aimed to identify synovial fluid PTAA biomarkers using cytokine analysis and metabolic profiling.

Methods:

Ankle joint synovial fluid was obtained from 20 patients with PTAA and 20 patients with no ankle pain and no radiographic evidence of ankle arthritis (control group). Synovial fluid samples were analyzed for IFN-γ, TNF-α, MIP-1β, MCP-1, IL-1β, IL-1Ra, IL-4, IL-6, IL-8, IL-10, IL-13, and IL-15 using ELISA and for more than 3000 metabolites using liquid and gas chromatography with mass spectroscopy. To compare presence of cytokines and metabolites between groups, t tests were used. Random forest analysis was performed on metabolites to determine whether control and PTAA samples could be differentiated based on metabolic profile.

Results:

IL-1Ra, IL-6, IL-8, IL-10, IL-15, and MCP-1 were significantly elevated in the PTAA group. In addition, 107 metabolites in the PTAA group were significantly altered, including derangement in amino acid, carbohydrate, lipid, and energy metabolism, extracellular matrix turnover, and collagen degradation. Random forest analysis yielded a predictive accuracy of 90% when using the metabolic profiles to distinguish between control and PTAA samples.

Conclusion:

This study identified inflammatory cytokines and metabolites present in the synovial fluid of PTAA.

Clinical Relevance:

Several of these entities have previously been implicated in rheumatoid arthritis and osteoarthritis of the knee, but many could potentially be used as novel biomarkers of PTAA. Most importantly, the findings suggest that metabolites could be used to distinguish synovial fluid from patients with PTAA.