bluuebunny/crossref_metadata_2025 huggingface dataset:
Malignant Otitis Externa: An Asian Perspective on Treatment Outcomes and Prognostic Factors
Authors: Loh Shaun , Loh Woei Shyang
Published: April 2013

Objective

Malignant otitis externa (MOE) is a severe disease with varying outcomes. Despite advances in antibiotic treatment, a significant proportion still succumbs to this disease. We aimed to analyze the effect of clinical factors on prognosis and to review treatment outcomes in our institution.

Study Design

Case series with retrospective chart review of MOE cases from 2006 to 2011.

Setting

Department of Otolaryngology–Head and Neck Surgery, National University Hospital, Singapore, a tertiary referral center.

Subjects and Methods

Patients with MOE admitted for treatment were studied and divided into 2 outcome groups depending on response to a 6‐week course of intravenous antibiotics. Demographic and disease factors were analyzed with regard to outcome.

Results

Nineteen cases were analyzed. Disease resolved in 63.2% after 6 weeks of antibiotics. Mortality was 21.1%. Age, diabetic control, duration of diagnostic delay, cranial nerve involvement, and inflammatory markers were not found to predict prognosis. Erythrocyte sedimentation rate and C‐reactive protein levels correlated with disease activity and can be used to monitor progress. Clival involvement was associated with persistent disease (P =. 002). Only 63.2% of cases had positive cultures. Pseudomonas aeruginosa was the main organism, and 33.3% of isolates were multidrug resistant. Outcome was not different in cases where culture‐directed therapy was employed vs those where empirical ceftazidime and fluoroquinolone were used (P =. 650).

Conclusion

Malignant otitis externa remains an insidious disease with significant mortality. Involvement of the clivus portends a poorer prognosis. Combination therapy with intravenous ceftazidime and oral fluoroquinolone remains relevant despite concerns of culture‐negative cases and multidrug‐resistant Pseudomonas.
In vitro Evaluation of Sialyl Lewis X Relationship with Head and Neck Cancer Stem Cells
Authors: Czerwinski Michael J. , Desiderio Vincenzo , Shkeir Omar , Papagerakis Petros , Lapadatescu Martian C. , Owen John H. , Athanassiou‐Papaefthymiou Maria , Zheng Li , Papaccio Gianpaolo , Prince Mark E. , Papagerakis Silvana
Published: April 2013

Objective

To evaluate in vitro the potential links between sialyl Lewis X (sLeX) and cancer stem cells (CSC) in head and neck squamous cell carcinoma (HNSCC). HNSCC is an aggressive malignancy with high mortality mainly due to metastasis. CSC have emerged as important players in HNSCC metastasis. sLeX is a tetrasaccharide carbohydrate known to play a key role in metastatic dissemination by promoting binding of the tumor cells to the endothelium.

Study Design

Experimental, in vitro.

Setting

Laboratory of Head and Neck Cancer Metastasis, University of Michigan.

Subjects and Methods

A panel of stage‐ and anatomic‐site specific primary and metastatic HNSCC cell lines was assessed by flow cytometry to quantify sLeX relative expression levels. Serum‐free conditioned media from the same HNSCC lines was collected over a time course of 72 hours and assessed by Western blot for secreted sLeX expression. Representative HNSCC cell lines were cultured as floating orospheres (condition that enhance CSC growth) or under normal adherent conditions and characterized by flow cytometry for CSC markers (CD44, aldehyde dehydrogenase [ALDH]) comparatively with sLeX expression.

Results

sLeX is predominantly expressed in carcinomas originating from the oral cavity. Secreted sLeX is also found to be high in oral carcinomas and increased over the analyzed time course. Floating orospheres were strongly positive for CD44 and ALDH, confirming CSC enrichment of the orospheres. Tumor cells grown as orospheres are 95% to 100% positive for sLeX compared to 10% to 40% of adherent counterpart.

Conclusion

These studies provide the first evidence of sLeX relationship with CSC in HNSCC.
European guidelines for sclerotherapy in chronic venous disorders
Authors: Rabe E , Breu FX , Cavezzi A , Smith P Coleridge , Frullini A , Gillet JL , Guex JJ , Hamel-Desnos C , Kern P , Partsch B , Ramelet AA , Tessari L , Pannier F ,   for the Guideline Group
Published: April 2013

Aim

Sclerotherapy is the targeted chemical ablation of varicose veins by intravenous injection of a liquid or foamed sclerosing drug. The treated veins may be intradermal, subcutaneous, and/or transfascial as well as superficial and deep in venous malformations. The aim of this guideline is to give evidence-based recommendations for liquid and foam sclerotherapy.

Methods

This guideline was drafted on behalf of 23 European Phlebological Societies during a Guideline Conference on 7–10 May 2012 in Mainz. The conference was organized by the German Society of Phlebology. These guidelines review the present state of knowledge as reflected in published medical literature. The regulatory situation of sclerosant drugs differs from country to country but this has not been considered in this document. The recommendations of this guideline are graded according to the American College of Chest Physicians Task Force recommendations on Grading Strength of Recommendations and Quality of Evidence in Clinical Guidelines.

Results

This guideline focuses on the two sclerosing drugs which are licensed in the majority of the European countries, polidocanol and sodium tetradecyl sulphate. Other sclerosants are not discussed in detail. The guideline gives recommendations concerning indications, contraindications, side-effects, concentrations, volumes, technique and efficacy of liquid and foam sclerotherapy of varicose veins and venous malformations.
Safety in pediatric imaging: an update
Authors: Arthurs Owen John , Bj⊘rkum Alvhild Alette
Published: April 2013

Many assumptions are made when imaging children. In particular a judgement is made regarding how safe or unsafe each imaging modality is, using relatively arbitrary definitions and distinctions, due to the lack of robust scientific data. Here, the latest evidence is reviewed, particularly regarding the medical exposure to ionizing radiation (X-rays and CT) and MRI in childhood. The best evidence currently available suggests a small but convincing risk of cumulative low-dose ionizing radiation in children. Given our predictions for the children imaged today, it seems reasonable to pursue non-ionizing-based techniques wherever possible, although there is emerging evidence that MRI and ultrasound may have hitherto unknown effects. As our knowledge base expands, we must continually review our practice in light of the latest scientific data.
Gastroduodenal artery recanalization after transcatheter fibered coil embolization for prevention of hepaticoenteric flow: incidence and predisposing technical factors in 142 patients
Authors: Enriquez Jose , Javadi Sanaz , Murthy Ravi , Ensor Joe , Mahvash Armeen , Abdelsalam Mohamed E , Madoff David C , Wallace Michael J , Avritscher Rony
Published: April 2013

Background

Prophylactic occlusion of extrahepatic vessels prior to radioembolization or chemotherapy infusion is an effective method to prevent gastrointestinal complications. Unfortunately, vascular recanalization can occur.

Purpose

To retrospectively determine the rate and technical factors associated with gastroduodenal artery (GDA) recanalization after transcatheter occlusion with fibered coils.

Material and Methods

Patients with hepatic malignancy who underwent fibered coil occlusion of the GDA origin for radioembolization or hepatic arterial chemotherapy infusion with at least one subsequent hepatic angiogram between March 2006 and January 2011 were included. One hundred and forty-two patients (men, 71; women, 71) met study criteria. Hepatic arteriograms were reviewed to determine the frequency of arterial recanalization. Additional parameters included: patients’ demographics, GDA diameter, length of coil pack, distance between GDA origin and most cephalad coil, persistent flow at the conclusion of the initial GDA occlusion procedure, platelet count, and international normalized ratio (INR). Chi-square test and pooled t-test were used to compare the two groups. Prospective multivariate analysis was performed with a logistic regression model.

Results

Twenty-nine of 142 patients (20.4%) experienced GDA recanalization. The distance between the GDA origin and most cephalad coil was significantly greater in the recanalization group than in the non-recanalization group (9.6 mm vs. 12.6 mm, P = 0.01). A prospective multivariate analysis established that the further the coil was from the origin the more likely the GDA was to recanalize. The two groups did not differ on the basis of any other factors examined.

Conclusion

GDA origin recanalization after fibered coil occlusion is common. The distance between the GDA origin and most cephalad coil appears to be a predisposing factor for recanalization. Familiarity with this phenomenon is beneficial to reduce the likelihood of gastrointestinal tract complications during hepatic locoregional therapy.
Sigmoid sinus diverticulum and pulsatile tinnitus: analysis of CT scans from 15 cases
Authors: Liu Zhaohui , Chen Chengfang , Wang Zhenchang , Gong Shusheng , Xian Junfang , Wang Yongzhe , Liang Xihong , Ma Xiaobo , Li Yi
Published: April 2013

Background

Although the imaging features of sigmoid sinus diverticulum induced pulsatile tinnitus (PT) have been presented in some extent, detailed imaging findings still have not been systematically evaluated and precise diagnostic radiographic criteria has not been established.

Purpose

To examine the computed tomography (CT) characteristics of sigmoid sinus diverticulum accompanied with PT.

Material and Methods

Fifteen PT patients with sigmoid sinus diverticula proven by surgery were recruited after consenting. CT images of 15 patients were obtained and analyzed, including features of diverticula, brain venous systems, integrity of the sigmoid plate, and the degree of temporal bone pneumatization.

Results

Sigmoid sinus diverticulum was located on the same side of PT in 15 patients. Diverticula originated at the superior curve of the sigmoid sinus in 11 patients and the descending segment of the sigmoid sinus in four patients. Sigmoid sinus diverticula focally eroded into the adjacent mastoid air cells in 12 patients and mastoid cortex in three patients. Among eight patients with unilateral dominant brain venous systems, the diverticula were seen on the dominant side in seven patients and non-dominant side in one patient. In contrast, the other seven patients showed co-dominant brain venous systems, with three presenting diverticula on the right side and four on the left. More notably, dehiscent sigmoid plate on the PT side was demonstrated in all patients. In addition, temporal bone hyper-pneumatization was found in nine patients, good and moderate pneumatization in three patients, respectively.

Conclusion

Dehiscent sigmoid plate and extensive temporal bone pneumatization are two important imaging characteristics of the PT induced by sigmoid sinus diverticulum.
Non-enhanced MR angiography of renal arteries: comparison with contrast-enhanced MR angiography
Authors: Angeretti MG , Lumia D , Canì A , Barresi M , Cardim L Nocchi , Piacentino F , Maresca AM , Novario R , Genovese EA , Fugazzola C
Published: April 2013

Background

The main causes of renal artery stenosis (RAS) are atherosclerosis and fibromuscular dysplasia. Despite contrast-enhanced magnetic resonance angiography (CE-MRA) being a safe and reliable method for diagnosis of RAS especially in young individuals, recently it has been possible to adopt innovative technologies that do not require paramagnetic contrast agents.

Purpose

To assess the accuracy of steady-state free-precession (SSFP) non-contrast-enhanced magnetic resonance angiography (NC-MRA) by using a 1.5 T MR scanner for the detection of renal artery stenosis, in comparison with breath-hold CE-MRA as the reference standard.

Material and Methods

Sixty-three patients (33 men, 30 women) with suspected renovascular hypertension (RVHT) were examined by a 1.5T MR scanner; NC-MRA with an electrocardiography (ECG)-gated SSFP sequence was performed in 58.7% (37/63) of patients; in 41.3% (26/63) of patients a respiratory trigger was used in addition to cardiac gating. CE-MRA, with a three-dimensional gradient echo (3D-GRE) T1-weighted sequence, was performed in all patients within the same session. Maximum intensity projection (MIP) image quality, number of renal arteries, and the presence of stenosis were assessed by two observers (independently for NC-MRA and together for CE-MRA). The agreement between NC-MRA and CE-MRA as well as the inter-observer reproducibility were calculated with Bland-Altman plots.

Results

MIP image quality was considered better for NC-MRA. NC-MRA identified 143 of 144 (99.3%) arteries detected by CE-MRA (an accessory artery was not identified). Fourteen stenoses were detected by CE-MRA (11 atherosclerotic, 3 dysplastic) with four of 14 (28.5%) significant stenosis. Bland-Altman plot demonstrated an excellent concordance between NC-MRA and CE-MRA; particularly, the reader A evaluated correctly all investigated arteries, while over-estimation of two stenoses occurred for reader B. Regarding NC-MRA, inter-observer agreement was excellent.

Conclusion

NC-MRA is a valid alternative to CE-MRA for the assessment of renal arteries.
Predicting local recurrence following breast-conserving treatment: parenchymal signal enhancement ratio (SER) around the tumor on preoperative MRI
Authors: Kim Mi Young , Cho Nariya , Koo Hye Ryoung , Yun Bo La , Bae Min Sun , Chie Eui Kyu , Moon Woo Kyung
Published: April 2013

Background

The level of background parenchymal enhancement around tumor is known to be associated with breast cancer risk. However, there is no study investigating predictive power of parenchymal signal enhancement ratio (SER) around tumor for ipsilateral breast tumor recurrence (IBTR).

Purpose

To investigate whether the breast parenchymal SER around the tumor on preoperative dynamic contrast-enhanced magnetic resonance imaging (MRI) is associated with subsequent IBTR in breast cancer patients who had undergone breast-conserving treatment.

Material and Methods

Nineteen consecutive women (mean age, 44 years; range, 34–63 years) with breast cancer who developed IBTR following breast-conserving treatment and 114 control women matched for age, as well as T and N stages were included. We compared the clinicopathologic features of the two groups including nuclear grade, histologic grade, hormonal receptor status, human epidermal growth factor receptor-2 (HER-2) status, lymphovascular invasion, negative margin width, use of adjuvant therapy, and parenchymal SER around the tumor on preoperative DCE-MRI. The SER was measured on a slice showing the largest dimension of the tumor. Multivariate conditional logistic regression analysis was used to identify independent factors associated with IBTR.

Results

In univariate analysis, ER negativity (odds ratio [OR] = 4.7; P = 0.040), PR negativity (OR = 4.0; P = 0.013), HER-2 positivity (OR = 3.6; P = 0.026), and a parenchymal SER greater than 0.53 (OR = 23.3; P = 0.011) were associated with IBTR. In multivariate analysis, ER negativity (OR = 3.8; P = 0.015) and a parenchymal SER greater than 0.53 (OR = 13.2; P = 0.040) on preoperative MRI were independent factors associated with IBTR.

Conclusion

In addition to ER negativity, a higher parenchymal SER on preoperative MRI was an independent factor associated with subsequent IBTR in patients with breast cancer who had undergone breast-conserving treatment.
Principles for Valid Histopathologic Scoring in Research
Authors: Gibson-Corley K. N. , Olivier A. K. , Meyerholz D. K.
Published: April 2013

Histopathologic scoring is a tool by which semiquantitative data can be obtained from tissues. Initially, a thorough understanding of the experimental design, study objectives, and methods is required for the pathologist to appropriately examine tissues and develop lesion scoring approaches. Many principles go into the development of a scoring system such as tissue examination, lesion identification, scoring definitions, and consistency in interpretation. Masking (aka “blinding”) of the pathologist to experimental groups is often necessary to constrain bias, and multiple mechanisms are available. Development of a tissue scoring system requires appreciation of the attributes and limitations of the data (eg, nominal, ordinal, interval, and ratio data) to be evaluated. Incidence, ordinal, and rank methods of tissue scoring are demonstrated along with key principles for statistical analyses and reporting. Validation of a scoring system occurs through 2 principal measures: (1) validation of repeatability and (2) validation of tissue pathobiology. Understanding key principles of tissue scoring can help in the development and/or optimization of scoring systems so as to consistently yield meaningful and valid scoring data.
Differential stimulation of neurotrophin release by the biocompatible nano-material (carbon nanotube) in primary cultured neurons
Authors: Kim Yun Gi , Kim Jong Wan , Pyeon Hee Jang , Hyun Jung Keun , Hwang Ji-Young , Choi Seong-Jun , Lee Ja-Yeon , Deák Ferenc , Kim Hae-Won , Lee Young Il
Published: April 2013

In order to develop novel, effective therapies for central nervous system regeneration, it is essential to better understand the role of neurotrophic factors and to design, accordingly, better artificial scaffolds to support both neurite outgrowth and synapse formation. Both nerve growth factor and brain-derived neurotrophic factor are major factors in neural survival, development, synaptogenesis, and synaptic connectivity of primary cultured neurons. As a prime candidate coating material for such neural cultures, carbon nanotubes offer unique structural, mechanical, and electrical properties. In this study, carbon nanotubes coated glass-coverslips were used as the matrix of a primary neural culture system used to investigate the effects of carbon nanotubes on neurite outgrowth and nerve growth factor/brain-derived neurotrophic factor release and expression. For these purposes, we performed comparative analyses of primary cultured neurons on carbon nanotubes coated, non-coated, and Matrigel-coated coverslips. The morphological findings showed definite carbon nanotubes effects on the neurite outgrowths and synaptogenic figures in both cortical and hippocampal neurons when compared with the non-coated negative control. Although the carbon nanotubes did not change neurotrophin expression levels, it stimulated brain-derived neurotrophic factor release into the media from both types of neurons. Accordingly, we suggest a different mechanism of action between carbon nanotubes and Matrigel in relation to the specific neurotrophic factors. Since carbon nanotubes supply long-term extracellular molecular cues for the survival and neurite outgrowths of cultured neurons, the results from this study will contribute to an understanding of carbon nanotubes biological effects and provide new insight into their role in the secretion of neurotrophic factors.
Functional Limitations in Older Adults Who Have Cognitive Impairment Without Dementia
Authors: Gure Tanya R. , Langa Kenneth M. , Fisher Gwenith G. , Piette John D. , Plassman Brenda L.
Published: April 2013

Objective:

To characterize the prevalence of functional limitations among older adults with cognitive impairment without dementia (CIND).

Methods:

Secondary data analysis was performed using the Aging, Demographics, and Memory Study data set. A total of 856 individuals aged ≥ 71 years were assigned to 3 diagnostic cognitive categories. A questionnaire was completed by a proxy informant regarding functional limitations for 744 of the 856 respondents.

Results:

Of the 744 patients, 263 (13.9%) had dementia, 201 (21.3%) had CIND, and 280 (64.8%) had normal cognition. Informants reported ≥1 instrumental activities of daily living (ADLs) limitation in 45% of the patients with CIND compared to 13% of the patients with normal cognition and 85% of the patients with dementia ( P < .001). The ADL impairments among individuals with CIND were primarily attributed to physical health problems (n = 41; 40%).

Conclusions:

Many individuals with CIND have impairment in a range of complex and basic daily activities, largely due to physical health problems.
Innovation sustainability in challenging health-care contexts: Embedding clinically led change in routine practice
Authors: Martin Graham P , Weaver Simon , Currie Graeme , Finn Rachael , McDonald Ruth
Published: April 2013

The need for organizational innovation as a means of improving health-care quality and containing costs is widely recognized, but while a growing body of research has improved knowledge of implementation, very little has considered the challenges involved in sustaining change – especially organizational change led ‘bottom-up’ by frontline clinicians. This study addresses this lacuna, taking a longitudinal, qualitative case-study approach to understanding the paths to sustainability of four organizational innovations. It highlights the importance of the interaction between organizational context, nature of the innovation and strategies deployed in achieving sustainability. It discusses how positional influence of service leads, complexity of innovation, networks of support, embedding in existing systems, and proactive responses to changing circumstances can interact to sustain change. In the absence of cast-iron evidence of effectiveness, wider notions of value may be successfully invoked to sustain innovation. Sustainability requires continuing effort through time, rather than representing a final state to be achieved. Our study offers new insights into the process of sustainability of organizational change, and elucidates the complement of strategies needed to make bottom-up change last in challenging contexts replete with competing priorities.
Utilizing experience-based co-design to improve the experience of patients accessing emergency departments in New South Wales public hospitals: An evaluation study
Authors: Piper Donella , Iedema Rick , Gray Jane , Verma Raj , Holmes Lee , Manning Nicole
Published: April 2013

Summary

Background

This paper presents the findings of three multisite evaluations of Experience-Based Co-design (EBCD) programmes conducted in Emergency Departments (EDs) and associated departments in seven public hospitals in New South Wales, Australia.

Method

Data for the evaluations were derived from: EBCD documentation provided by the participating sites; interviews with 117 key informants; performance data and the policy and academic literature on EBCD.

Results

Respondents described EBCD as a successful and sustainable method of improving the individual patient experience and the overall quality of a health service. Demonstrated successes were reported to lead to aspects of the EBCD approach spreading within services. However, like any quality improvement activity, EBCD was not without its challenges. The principal challenge particular to the EBCD projects outlined here was their deployment in ED settings. Because of their ambulant patient populations, these settings made sustaining consumer engagement for the duration of the project problematic and required tailoring EBCD to accommodate consumers’ involvement preferences and constraints.

Conclusion

The primary strength of EBCD over and above other service development methodologies was reported to be its ability to bring about improvements simultaneously in both the operational efficiency and the inter-personal dynamics of care. However, careful consideration must be given to the constraints inherent in transient patient specialties and what needs to be done to tailor EBCD to suit the particular setting in which it is deployed.
Active vibration control for a CNC milling machine
Authors: Ford DG , Myers A , Haase F , Lockwood S , Longstaff A
Published: April 2013

There is a requirement for improved three-dimensional surface characterisation and reduced tool wear when modern computer numerical control (CNC) machine tools are operating at high cutting velocities, spindle speeds and feed rates. For large depths of cut and large material removal rates, there is a tendency for machines to chatter caused by self-excited vibration in the machine tools leading to precision errors, poor surface finish quality, tool wear and possible machine damage. This study illustrates a method for improving machine tool performance by understanding and adaptively controlling the machine structural vibration. The first step taken is to measure and interpret machine tool vibration and produce a structural model. As a consequence, appropriate sensors need to be selected and/or designed and then integrated to measure all self-excited vibrations. The vibrations of the machine under investigation need to be clearly understood by analysis of sensor signals and surface finish measurement. The active vibration control system has been implemented on a CNC machine tool and validated under controlled conditions by compensating for machine tool vibrations on time-varying multi-point cutting operations for a vertical milling machine. The design of the adaptive control system using modelling, filtering, active vibration platform and sensor feedback techniques has been demonstrated to be successful.
Development and experimental research on circumferential impulse microturbine power generation system
Authors: Zhang L , Tang GZ , Liao ZB , Shang HC
Published: April 2013

Circumferential impulse microturbine is a key component of the micro-electro-mechanical system and provides power to the latter. An innovative concept of microturbine power generation system was presented, and prototype improved circumferential impulse microturbine power generation systems were developed, and their output performances were tested. It is validated that the system can operate at a high speed in a dynamic equilibrium state using rolling bearings, and it is found that the output power and rotational speed of a six-blade turbine hollow-cup coil structure is higher than the output power and rotational speed of a six-blade turbine iron-core coil structure. The maximum output power of the eight-blade turbine hollow-cup coil power generation system is 1.1 W, and the maximum turbine rotational speed is 55,000 r/min. The maximum output power of the eight-blade turbine hollow-cup coil system increases up to 25% when compared to the six-blade turbine hollow-cup coil system and increases up to 83% when compared to the six-blade turbine iron-core coil system.
Pairwise diversity ranking of polychotomous features for ensemble physiological signal classifiers
Authors: Gupta Lalit , Kota Srinivas , Molfese Dennis L , Vaidyanathan Ravi
Published: April 2013

It is well known that fusion classifiers for physiological signal classification with diverse components (classifiers or data sets) outperform those with less diverse components. Determining component diversity, therefore, is of the utmost importance in the design of fusion classifiers that are often employed in clinical diagnostic and numerous other pattern recognition problems. In this article, a new pairwise diversity-based ranking strategy is introduced to select a subset of ensemble components, which when combined will be more diverse than any other component subset of the same size. The strategy is unified in the sense that the components can be classifiers or data sets. Moreover, the classifiers and data sets can be polychotomous. Classifier-fusion and data-fusion systems are formulated based on the diversity-based selection strategy, and the application of the two fusion strategies are demonstrated through the classification of multichannel event-related potentials. It is observed that for both classifier and data fusion, the classification accuracy tends to increase/decrease when the diversity of the component ensemble increases/decreases. For the four sets of 14-channel event-related potentials considered, it is shown that data fusion outperforms classifier fusion. Furthermore, it is demonstrated that the combination of data components that yield the best performance, in a relative sense, can be determined through the diversity-based selection strategy.
In vitro investigation of friction at the interface between bone and a surgical instrument
Authors: Parekh Jugal , Shepherd Duncan ET , Hukins David WL , Hingley Carl , Maffulli Nicola
Published: April 2013

This study investigated the friction between surgical instruments and bone to aid improvements to instrument design. The bases of orthopaedic surgical instruments are usually made of metal, especially stainless steel. Silicone elastomer was chosen as an alternate biocompatible material, which would be compliant on the bone surface when used as the base of an instrument. The coefficient of static friction was calculated at the bone/material interface in the presence of a synthetic solution that had a comparable viscosity to that of blood, to assess the friction provided by each base material. Three types of silicone elastomers with different hardnesses (Shore A hardness 23, 50 and 77) and three distinct stainless steel surfaces (obtained by spark erosion, sand blasting and surface grinding) were used to assess the friction provided by the materials on slippery bone. The bone specimens were taken from the flattest region of the femoral shaft of a bovine femur; the outer surfaces of the specimens were kept intact. In general, the stainless steel surfaces exhibited higher values of coefficient of static friction, compared to the silicone elastomer samples. The stainless steel surface finished by spark erosion (surface roughness Ra = 8.9 ± 1.6 µm) had the highest coefficient value of 0.74 ± 0.04. The coefficient values for the silicone elastomer sample with the highest hardness (Dow Corning Silastic Q7-4780, Shore A hardness 77) was not significantly different to values provided by the stainless steel surface finished by sand blasting (surface roughness Ra = 2.2 ± 0.1 µm) or surface grinding (surface roughness Ra = 0.1 ± 0.0 µm). Based on the results of this study, it is concluded that silicone could be a potentially useful material for the design of bases of orthopaedic instruments that interface with bone.
How Visual Short-Term Memory Maintenance Modulates Subsequent Visual Aftereffects
Authors: Saad Elyana , Silvanto Juha
Published: April 2013

Prolonged viewing of a visual stimulus can result in sensory adaptation, giving rise to perceptual phenomena such as the tilt aftereffect (TAE). However, it is not known if short-term memory maintenance induces such effects. We examined how visual short-term memory (VSTM) maintenance modulates the strength of the TAE induced by subsequent visual adaptation. We reasoned that if VSTM maintenance induces aftereffects on subsequent encoding of visual information, then it should either enhance or reduce the TAE induced by a subsequent visual adapter, depending on the congruency of the memory cue and the adapter. Our results were consistent with this hypothesis and thus indicate that the effects of VSTM maintenance can outlast the maintenance period.
The Curse of Planning
Authors: Otto A. Ross , Gershman Samuel J. , Markman Arthur B. , Daw Nathaniel D.
Published: April 2013

A number of accounts of human and animal behavior posit the operation of parallel and competing valuation systems in the control of choice behavior. In these accounts, a flexible but computationally expensive model-based reinforcement-learning system has been contrasted with a less flexible but more efficient model-free reinforcement-learning system. The factors governing which system controls behavior—and under what circumstances—are still unclear. Following the hypothesis that model-based reinforcement learning requires cognitive resources, we demonstrated that having human decision makers perform a demanding secondary task engenders increased reliance on a model-free reinforcement-learning strategy. Further, we showed that, across trials, people negotiate the trade-off between the two systems dynamically as a function of concurrent executive-function demands, and people’s choice latencies reflect the computational expenses of the strategy they employ. These results demonstrate that competition between multiple learning systems can be controlled on a trial-by-trial basis by modulating the availability of cognitive resources.
Two Signatures of Implicit Intergroup Attitudes
Authors: Dunham Yarrow , Chen Eva E. , Banaji Mahzarin R.
Published: April 2013

Long traditions in the social sciences have emphasized the gradual internalization of intergroup attitudes and the putatively more basic tendency to prefer the groups to which one belongs. In four experiments ( N = 883) spanning two cultures and two status groups within one of those cultures, we obtained new evidence that implicit intergroup attitudes emerge in young children in a form indistinguishable from adult attitudes. Strikingly, this invariance from childhood to adulthood holds for members of socially dominant majorities, who consistently favor their in-group, as well as for members of a disadvantaged minority, who, from the early moments of race-based categorization, do not show a preference for their in-group. Far from requiring a protracted period of internalization, implicit intergroup attitudes are characterized by early enculturation and developmental invariance.
Rituximab treatment for ‘rhupus syndrome’: clinical and power-Doppler ultrasonographic monitoring of response. A longitudinal pilot study
Authors: Piga M , Gabba A , Cauli A , Garau P , Vacca A , Mathieu A
Published: April 2013

Objective

To evaluate the safety and efficacy of rituximab in patients suffering from rhupus unresponsive to therapy with non-biological disease-modifying anti-rheumatic drugs (DMARDs).

Methods

Six patients fulfilling criteria for both rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) and with a DAS28 score >5.1 were enrolled to receive two fortnightly 1000 mg rituximab doses at baseline and after 28 weeks. All patients underwent clinical, laboratory, and power- Doppler (PD) ultrasonographic (US) assessment at baseline and after 14, 28 and 56 weeks.

Results

A sustained improvement in DAS28, SLEDAI, HAQ, laboratory markers and ultrasound indices together with a significant reduction in the daily dose of prednisone were observed throughout follow-up.

Conclusion

Rituximab may be a safe and effective therapeutic option in refractory rhupus patients.
Poverty as a Contextual Factor Affecting Sexual Health Behavior Among Female Sex Workers in India
Authors: Dasgupta Satarupa
Published: April 2013

A thorough understanding of the environmental and structural factors that precipitate unsafe sexual practices is necessary for HIV/AIDS-prevention research among high-risk population groups like commercial sex workers. I examined how poverty contextualizes sexual health behavior, including condom compliance among commercial female sex workers in a red light district in Calcutta, India. For my research I did an ethnographic study and conducted in-depth interviews of 37 commercial female sex workers. I found that poverty, instead of serving as a catalyst for poor health choices among sex workers, acted as an impetus for pursuing safe sex practices and remaining healthy. The results indicate that sex work, poverty, and health do not always have a paradoxical relationship.
A Psychometric Evaluation of the Career Decision Self-Efficacy Scale–Short Form With Turkish University Students
Authors: Buyukgoze-Kavas Aysenur
Published: April 2013

The current study aimed to examine the psychometric properties of the Career Decision Self-Efficacy scale–Short Form (CDSES-SF) in a sample of 695 Turkish university students. Accordingly, internal reliability, test–retest reliability, convergent validity, and factor structure of the CDSES-SF were examined. The results indicated high internal and test–retest reliability for total scores. The evidence for the convergent validity was provided by a relatively high correlation between career decision-making self-efficacy and general self-efficacy. To estimate the factor structure of the scale, Betz, Klein, and Taylor’s five-factor model of the CDSES-SF, along with a number of empirically derived measurement models of the CDSES-SF were tested via confirmatory factor analyses. Only Gaudron’s four-factor model exhibited good model fit for the Turkish sample. The findings of this study are discussed in accordance with previous studies and the current cultural context of Turkey.
Descriptive Poems on a Qualitative Research With Young Smokers in Southern Nigeria
Authors: Egbe Catherine O.
Published: April 2013

These two poems come from my experience as a qualitative researcher in Nigeria where this method of research is not a very common phenomenon. I was dazed by the vast opportunity this method gives a researcher to dig deep into a research problem and be submerged into the world of participants. Understanding the experiences of young smokers and how they were influenced into picking up the habit was the aim of my study but I got more than what I asked for. These two poems give an insight into the experiences of cigarette smokers and the researcher as captured during the research. Journeys had to be made to get willing participants and when the willing participants were found, it was a worthy ride from cities to suburbs.
Decentralization and Tax Competition between Asymmetrical Local Governments
Authors: Carbonnier Clément
Published: April 2013

This article presents a model of tax competition between an arbitrarily large number of asymmetrical jurisdictions. Tax competition induces lower corporate taxes and lower public input provision than does tax coordination. This bias decreases with respect to the size and number of jurisdictions. Tax competition constitutes a cost of decentralization that may balance the gains presented by the decentralization theorem. A French panel of municipalities and intermunicipal jurisdictions is used to test these results, which are confirmed. Furthermore, the corporate tax increase due to cooperation leads to an increase in the corporate tax base: the fully decentralized situation is suboptimal.
No Base Left Behind
Authors: Nguyen-Hoang Phuong , Yeung Ryan , Bogin Alexander
Published: April 2013

This study examines the effects of military base closures on educational expenditures and student outcomes with a national panel data set of school districts between 1990 and 2002. We adopt difference-in-differences estimation in combination with propensity score matching and instrumental variables techniques to estimate these effects. We find that per-pupil spending increases by 25.2 percent in the first year, where it remains. We also find a substantial decrease in graduation rates, but an improving trend occurs in the years after the closure.
Effect and Clinical Implications of the Low-Energy Diode Laser on Bone Cell Proliferation
Authors: Huertas Rosa Medina , Luna-Bertos Elvira De , Ramos-Torrecillas Javier , Leyva Francisco Medina , Ruiz Concepción , García-Martínez Olga
Published: April 2013

Laser is a simple, noninvasive technique that has proven useful for treating damaged tissue. However, its effects on bone regeneration and the mechanisms involved are poorly understood. The objective of this study was to evaluate the effects on MG-63 cell proliferation of application of a pulsed diode laser (Ezlase) of 940 nm at low energy levels. After 24 hr of culture, osteoblasts underwent pulsed laser radiation at 0.5, 1, 1.5, and 2 W and fluences of 1–5 J. A control group was not irradiated. After the treatment, cells were incubated for 24 hr, and cell proliferation was analyzed using a spectrophotometric measure of cell respiration (MTT assay). Results were expressed as percentage proliferation versus controls. At 24-hr culture, cell proliferation was increased in laser-treated cells at intensities of 0.5, 1, and 1.5 W/cm2 versus controls; the energy density was positively correlated with cell growth, which reached a peak at 3 J and decreased at higher fluences. The use of pulsed low-level laser with low-energy density range thus appears to exert a biostimulatory effect on bone tissue. Although the data on cell proliferation are robust, in-depth investigation is required into the effect of these irradiation doses on other cell parameters. The present findings demonstrate that laser therapy could be highly useful in tissue regeneration in different clinical settings, including nursing, physical therapy, dentistry, and traumatology.
Scenes of exclusion: Historical transformation and material limitations to Pawnee gender representation
Authors: Pugh Daniel
Published: April 2013

Major shifts in gender roles were among the transformations that came to American Indian cultures with colonialism and American domination. Although a great number of scholars have explored these changes, explanations have typically been sought in mimetic performances of Western gender relationships among native communities and hegemonic restructuring of attitudes by outside agents. Material objects, however, were perhaps as powerful as human agents in driving these ideological shifts because they are capable of representing layers of cultural values even when actors are absent. By examining material objects as active social actors during focused social interactions, this article describes one of the many avenues by which new Euro-American attitudes were slowly introduced to the rhythms of Pawnee life.
Crafting authenticity: An ethnography of conservation practice
Authors: Jones Siân , Yarrow Thomas
Published: April 2013

This article explores how authenticity is produced through different forms of expertise and skill, as they are negotiated and aligned in the daily practices of conservation. Focusing on the traditional craft practices of stonemasons, the authors trace their relations to the broader nexus of experts responsible for conserving Glasgow Cathedral. They show that authenticity is a distributed property of distinct forms of expert practice as they intersect with one another and, crucially, with the material conditions of specific heritage sites. It is argued that, in the context of conservation practice, authenticity is neither a subjective, discursive construction nor a latent property of historic monuments waiting to be preserved. Rather it is a property that emerges through specific interactions between people and things.
A critical analysis of workforce development research use in the transformation of children’s services
Authors: Curran Tillie , Oliver Billie , Benjamin Cathy
Published: April 2013

This article is based on a study commissioned to find out how agencies providing children’s services in England used workforce development research in the transformation of children’s services. Workforce development research is primarily about how new organisational practices are learnt, embedded and developed. Survey and case study methods provided broad and in-depth data that was mapped against a typology developed to capture a diverse range of research activities.

Findings

Three cross-cutting themes were identified from the analysis: the involvement of children and young people in workforce development research; the development of reflective practice; and the significance of inter-organisational learning cultures. Workforce development research can contribute to a creative culture of inquiry shaping change processes especially where both practitioners and children and young people are involved. In some specialist areas a lack of engagement was attributed to the demands of complex practice and bureaucracy, but in other similar contexts, learning cultures were evident.

Application

Accounts of learning cultures producing active concepts of childhood link with ‘new’ childhood studies and contrast with accounts of crisis management informed by individualised models of ‘problem families’ highlighted in critiques of neo-liberal forms of government. The study shows that this opposition is not an inevitable consequence of complex practice or service configuration per se, but is contingent on a range of supporting factors such as partnerships with universities. To strengthen the exponential impact of research use illustrated, a participatory approach to organisational research strategy is advanced.
Systematic review: The nature and extent of social work research on substance use disorders treatment interventions among African Americans
Authors: Clark Trenette T , McGovern Patricia , Mgbeokwere Davena , Wooten Nikki , Owusu Hawa , McGraw Kathleen A
Published: April 2013

Little is known about the contribution made by social workers to empirical evidence on substance use disorders treatment, especially interventions for African Americans. This article presents a systematic review of 23 articles, presentations, and dissertations written by social workers that focus on substance use disorders treatment interventions with African Americans. The aim of this review is to estimate the extent of contribution made by social workers to the research knowledge base on substance use disorders treatment interventions that are effective among African Americans, and to assess the methodological quality of those studies.

Findings

The review shows social workers’ contributions to research examining substance use disorders treatment interventions with African Americans is inadequate and the methodological rigor of these studies is slightly below average. Of the 23 articles examined, few studies included only African American samples, and most investigated substance use disorders treatment interventions in samples with a small percentage of African American participants. Moreover, most of the reviewed studies were published between 1994 and 2010 in non-social work journals and were cited an average of 6.67 times.

Applications

The social work profession must increase its contribution to the empirical knowledge base on substance use disorders intervention research with African Americans because it is essential to the provision of culturally sensitive, evidence-based practice to African Americans. More quasi-experimental and experimental designs are needed to compare multiple evidence-based treatments across diverse populations, and to determine causality between treatment processes and outcomes.
Getting there … and back: how ethnographic commuting (by bicycle) shaped a study of Australian backyard technologists
Authors: Jungnickel Katrina
Published: April 2013

Attention in ethnographic fieldwork, and particularly in multi-sited studies, has traditionally focused on the movement of people, things and ideas across distributed points. Recently, interest has gained purchase, particularly in mobilities and science and technology studies, on how the researcher physically gets from one place to another for the purpose of exploring the bearing, if any, mobility decisions and positionalities have on the nature of study and findings. The article contributes to this literature by defining four kinds of ethnographic mobility and focusing specifically on how a researcher gets there and back, or what can be termed ethnographic commuting. It draws on research conducted in two groups of backyard technologists in Australia (an initial study of a grassroots wireless network, which, as a result of my ethnographic commuting, grew to include a freakbike community). I discuss how cycling, initially adopted as a convenient form of transport between fieldsites, became an unexpected tool of enquiry, opening up new sites for study, providing entry into related social groups, catalysing new ways of thinking and, ultimately, (re)shaping my research. I highlight lessons learned and offer suggestions for approaching the ethnographic commute.