bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility of mitral valve surgery using minimal extracorporeal circulation
Authors: Sjatskig J , Yilmaz A , van Boven JW , Sonker U , Waanders FG , Kloppenburg GTL
Published: March 2012

Aim:

Using minimal extracorporeal circulation (MECC) in isolated coronary artery bypass grafting or aortic valve replacement has been proven to be safe, feasible and superior compared to standard cardiopulmonary bypass (CPB) in terms of postoperative complications, total hospital stay and blood product transfusions. This feasibility study evaluates the clinical outcomes of mitral valve surgery performed with MECC.

Methods:

From March 2006 to January 2011, seventy-five patients who underwent mitral valve surgery performed with MECC (n=75) in our institution were retrospectively evaluated. Demographic characteristics, operative data and clinical outcomes were collected in a prospectively designed database.

Results:

The mean age was 68.8 ± 10.2 years with a EuroSCORE of 7.0 ± 2.3. Thirty-seven patients had a moderate left ventricular function (with a range of 30-40%). All patients except two had severe mitral valve incompetence (MI). Surgery was successful in all procedures. The mean duration of surgery was 210 ± 44 min (range 118-356 min). The mean CPB time was 128 ± 30 (range 67-249) min. The cross-clamp time was 99 ± 26 (range 48-205) min. There were no intraoperative perfusion problems or airlocks reported. The mean intensive care unit (ICU) length of stay was two days. Subsequent analysis showed a first postoperative haemoglobin value of 9.4 g/dL ± 1.7. There were no peroperative neurological complications. One patient developed an ischaemic cerebrovascular accident (CVA) on the forth postoperative day due to inadequate anticoagulation. Other postoperative complications included eight patients with pneumonia, one superficial wound infection, temporary renal insufficiency in two patients and four patients needed re-exploration for excessive postoperative leakage. Overall in-hospital mortality was four percent.

Conclusion:

Our results show, for the first time, that isolated or combined mitral valve surgery using MECC is feasible and safe.
The views of patients with severe chronic obstructive pulmonary disease on advance care planning: A qualitative study
Authors: MacPherson Anna , Walshe Catherine , O’Donnell Valerie , Vyas Aashish
Published: March 2012

Background:

Chronic obstructive pulmonary disease (COPD) is a major cause of death worldwide and there are concerns that end-of-life care for these patients is inadequate. Advance care planning is encouraged, with the hope that it will improve communication and avoid unwanted interventions, which have been particular concerns; in practice, these discussions rarely occur. We have little knowledge of the views of patients with COPD on advance care planning. Understanding this could help integrate advance care planning into the routine management of patients with COPD.

Aim:

To explore the views of people with severe COPD about advance care planning.

Design:

Qualitative design, with data collection incorporating audio recorded semi-structured interviews. Analysis followed a grounded theory approach.

Setting/participants:

Patients with severe COPD ( n =10, Gold Standards Framework criteria) were recruited from primary and secondary care settings.

Results:

Participants felt they had not been given enough information about their diagnosis and prognosis, and were keen for more discussion with healthcare professionals. They wanted more involvement in decisions about their treatment when those decisions were required. Participants were happy to discuss their general views about future care, but felt uncomfortable with the traditional model of binding ‘advance directives’.

Conclusions:

Considering advance care planning as a repeated process of discussion of prognosis, concerns and probable preferences for care would be more useful than encouraging binding advance decisions. Further research should assess the effectiveness of this approach. Local coordination of who is responsible for information provision is needed, and greater involvement of patients with COPD in management decisions as they arise.
Nanocomposite thermogel for controlled release of small proteins
Authors: Garripelli Vivek K , Jo Seongbong
Published: March 2012

A nanocomposite thermogel composed of Pluronic®-based multiblock copolymer and laponite nanoclay was developed to sustain delivery of low-molecular-weight proteins. The rapid release of low-molecular-weight proteins from multiblock copolymer thermogels has been a problem for sustained delivery but was solved by using nanocomposite thermogel. Lysozyme (Mw = 14,700), a relatively low-molecular-weight protein, was successfully loaded into and released from nanocomposite thermogel. In addition, interactions among multiblock copolymer, laponite, and lysozyme were studied in terms of gelation, micellization, particle size, and zeta potential. Critical micellization temperatures and sol–gel transition temperatures of multiblock copolymer solutions were lowered with laponite addition. Positively charged lysozyme was adsorbed onto anionic surface of laponite, which increased with an increase in the lysozyme concentration. Particle size and zeta potential of the laponite–lysozyme complex were also dependent on the lysozyme concentration. The nanocomposite thermogel sustained lysozyme release to 40 days, whereas lysozyme release from multiblock copolymer thermogel lasted for only 18 days. The structural stability of released lysozyme was confirmed by circular dichroism spectroscopy and differential scanning calorimetry.
Validating a Measure of Work Stress for Correctional Staff
Authors: Higgins George E. , Tewksbury Richard , Denney Andrew S.
Published: March 2012

The purpose of this study is to examine the structure of a measure of work stress. More specifically, the research investigated whether six items properly identified a latent measure of work stress for correctional staff. Using data from a nonrandom sample of correctional staff, the results of the structural equation model analysis supported the view that the six items form one latent construct. The implications of these results are presented as well.
Missouri: An Examination of the Relationship Between the Source of Referral to Juvenile Court and Severity of Sentencing Outcomes
Authors: D’Angelo Jill , Brown Michael P. , Strozewski Jillian
Published: March 2012

Aaron Cicourel conducted research in the 1960s on youths processed by the juvenile justice system, including the referral stage. His work described complex relationships and influences that affected juvenile justice decision making. Juvenile court data from the state of Missouri are used to conduct a partial replication of Cicourel’s work, focusing on the referral stage. The present study also extends the literature by examining the influence of legal and extralegal factors on disposition decisions for five referral sources (i.e., Social Service, School, Family, Juvenile Court, and Law Enforcement). The results suggest that the referral source is related to sentence outcome. The findings are supportive of contemporary theory and highlight the importance of studying context, role responsibilities, and stereotypes that may develop out of human experiences and affect decision making at the referral and disposition stages.
Cultural and Cosmopolitan
Authors: Balogun Oluwakemi M.
Published: March 2012

This article uses a comparative-case research design of two different national beauty pageants in Nigeria to ask how and why gendered nationalisms are constructed for different audiences and aims. Both contests claim to represent “true Nigerian womanhood” yet craft separate models of idealized femininity and present different nationalist agendas. I argue that these differences stem from two distinct representations of gendered national identities. The first pageant, “Queen Nigeria,” whose winners do not compete outside of Nigeria, brands itself as a Nigerian-based pageant, centered on a cultural-nationalist ideal, which is focused on revitalizing and appreciating Nigerian culture to unify the nation. In contrast, the second contest, “The Most Beautiful Girl in Nigeria,” utilizes “international standards” to select and send contestants to Miss World and Miss Universe, the top pageants in the world, and promotes a cosmopolitan-nationalist ideal, which remains concentrated on propelling and integrating Nigeria into the international arena.
Mechanical and tribological properties of polyamide-based composites modified by thermoplastic polyurethane
Authors: Zhou Shaofeng , Huang Jin , Zhang Qiaoxin
Published: March 2012

The structural and tribological behaviors sliding under different conditions of the novel polyamide (PA)-based composites blended by thermoplastic polyurethane (TPU) were investigated in this article. With a compatible structure shown by the fractured morphology and crystalline structure results, the toughness of the PA6-TPU composites was improved apparently. The friction coefficient of PA6-TPU composites would stabilize quickly at relatively low value, while their wear rate increased. Under a higher applied load condition, the friction coefficient and wear rate of the PA6-TPU composites increased apparently, attributing to lots of complex reasons. However, high sliding speed would be useful in the formation of thin and stable TPU transfer film, such that both the friction coefficient and wear rate of the PA6-TPU composites decreased at higher sliding speed. Morphology of worn surface of PA6-TPU composites revealed that the primary wear mechanism was adhesive wear and fatigue wear under the dry sliding condition. It is expected to provide some practical guidance for the application of polymer materials in the tribological field.
Nonoxidative thermal degradation kinetic of polyamide 6,6 reinforced with carbon nanotubes
Authors: Ribeiro B , Nohara LB , Oishi SS , Costa ML , Botelho EC
Published: March 2012

The thermal degradation of the polyamide 6,6 (abbreviated henceforth as PA 6,6) reinforced with different concentrations of carbon nanotubes (CNTs) was investigated by means of thermal analysis. In this study, the nanostructured composites were produced using 0.1, 0.5 and 1.0 wt% of CNT. X-ray diffraction analyses were performed in order to evaluate the crystallographic properties of nanostructured composite. The degradation kinetics of PA 6,6/CNT nanostructured composites were measured by thermogravimetric analysis at different heating rates under nitrogen flow. TGA experiments were performed to elucidate the thermal behavior and supply the data that characterize the degradation kinetic. The degradation parameter kinetics was determined using the Ozawa–Wall–Flynn (O-W-F) methods, which do not require knowledge of the reaction mechanism. In this work, the results show that the addition of CNT up to the amount of 0.5 wt% increases the thermal stability of PA 6,6.
Preparation of poly(vinyl alcohol)/clay hydrogel through freezing and thawing followed by electron beam irradiation for the treatment of wastewater
Authors: Ibrahim Sayeda M , El-Naggar Amal A
Published: March 2012

In this work, poly(vinyl alcohol) (PVA)/clay hydrogel based on various ratios of clay (20%, 50%, and 60%) were prepared using freezing and thawing techniques followed by electron beam (EB) irradiation at different irradiation doses (20, 25, and 30 kGy). The physicochemical property of such hydrogel in terms of gel fraction (%) and water uptake (%) was investigated. The structure and property of the hydrogel were investigated by x-ray diffraction (XRD) and scanning electron microscope (SEM). Thermal property was investigated using differential scanning calorimetry and thermogravimetric analysis. The results indicated that the gel fraction (%) increases on increasing the clay content in the hydrogel at all irradiation doses. The results obtained by XRD and SEM show an intercalation and exfoliation between PVA and clay. The occurrence of one Tg and Tm of the hydrogel indicates the presence of complete miscibility between PVA and clay. Also, the prepared hydrogel exhibit high thermal stability by increasing clay content in the hydrogel. It was found that the prepared PVA/clay hydrogel has a high water uptake, making it acceptable for the use in treatment of wastewater from heavy and toxic metal ions and dye wastes.
Effect of diisocyanates on the properties and morphology of epoxy/polyurethane interpenetrating polymer networks
Authors: Bakar M , Hausnerova B , Kostrzewa M
Published: March 2012

The present work investigates the effect of epoxy resin (EP) modification with polyurethanes (PURs) based on polyethylene glycol and two different diisocyanates: 4,4′-diphenylmethane diisocyanate (MDI) and 2,4-toluene diisocyanate (TDI). The impact strength of the material based on 15 wt% PUR with TDI was enhanced by 130%, while the critical stress intensity factor and the flexural strength of epoxy composition based on 5 wt% PUR with MDI increased by approximately 140% in comparison with unmodified EP. Fourier transform infrared spectroscopy confirmed the occurrence of chemical reaction between the hydroxyl groups of EP and isocyanate groups of PUR, explaining the improvement in the mechanical properties of EP. Moreover, scanning electron micrographs showed a rough surface with plastic yielding and several microcracks in the compositions containing TDI-based PUR and deformed leaf-like morphology with more elongated structure for the EP modified with MDI-based PUR.
Dynapenic Abdominal Obesity and Metabolic Risk Factors in Adults 50 Years of Age and Older
Authors: Sénéchal Martin , Dionne Isabelle J. , Brochu Martin
Published: March 2012

Objectives: To investigate the additive effect of dynapenia and abdominal obesity on metabolic risk factors in older adults. Method: A total of 3,007 men and women from the National Health and Nutrition Examination Survey (NHANES) study were categorized as follows: (a) non-dynapenic/non-abdominally obese (N-DYN/N-AO), (b) dynapenic/non-abdominally obese (DYN/N-AO), (c) non-dynapenic/abdominally obese (N-DYN/AO), (d) dynapenic/ abdominally obese (DYN/AO) based on waist circumference (WC) and leg muscle strength tertiles. Dependent variables were lipids, glucose, blood pressure, and other chronic conditions. Results: The DYN/AO group had lower plasma HDL-chol and higher triglyceride and glucose levels than N-DYN/N-AO and DYN/N-AO groups (all p ≤ .01). Higher plasma triglyceride was observed in the DYN/AO group compared with N-DYN/AO group ( p ≤ .01). The odds of having metabolic syndrome, cardiovascular diseases, and type II diabetes were higher in DYN/AO compared with DYN/N-AO and N-DYN/N-AO. Conclusion: DYN/AO older adults might be at greater risk of metabolic alterations than those displaying dynapenia alone or those with neither abdominal obesity nor dynapenia.
Lupus nephritis is more severe in children and adolescents than in older adults
Authors: Sato VAH , Marques IDB , Goldenstein PT , Carmo LPF , Jorge LB , Titan SMO , Barros RT , Woronik V
Published: March 2012

Objective: To evaluate clinicopathological features and treatment response in patients with lupus nephritis (LN), comparing the childhood- and late-onset forms of the disease. Methods: We retrospectively analyzed clinical presentation, treatment and evolution in patients diagnosed with LN by renal biopsy between 1999 and 2008. Patients were grouped by age—≤18 years ( n = 23); and ≥50 years ( n = 13)—and were followed for the first year of treatment. Results: The baseline features of the childhood- and late-onset groups, respectively, were as follows: mean age, 15 ± 2 and 54 ± 5 years; female gender, 87% and 92%; hypertension, 87% and 77%; Systemic Lupus Erythematosus Disease Activity Index, 29 ± 9 and 17 ± 7 ( p = 0.002); estimated glomerular filtration rate (eGFR), 86 ± 66 and 70 ± 18 ml/min; concurrent SLE/LN diagnosis, 90% and 15% ( p < 0.001); crescents on biopsy, 74% and 30% ( p = 0.02); activity index on biopsy, 4.8 ± 2.6 and 3.3 ± 1.9 ( p = 0.10); and interstitial fibrosis (>10%), 39% and 61% ( p = 0.08). Treatment consisted mainly of methylprednisolone, prednisone and intravenous cyclophosphamide, average cumulative doses being similar between the groups. After 12 months of treatment, the eGFR in the younger and older patients was 116 ± 62 and 78 ± 20 ml/min, respectively ( p = 0.005). Three of the younger patients progressed to dialysis at 12 months, compared with none of the older patients. Conclusion: Childhood-onset LN seems to be more severe than is late-onset LN.
Sensitivity analysis of piezoaeroelastic energy harvesters
Authors: Abdelkefi Abdessattar , Hajj Muhammad R , Nayfeh Ali H
Published: March 2012

We perform a sensitivity analysis of a piezoaeroelastic energy harvester consisting of a pitching and plunging rigid airfoil supported by flexural and torsional springs with a piezoelectric coupling attached to the plunge degree of freedom. We employ the nonintrusive formulation of the polynomial chaos expansion in terms of the multivariate Hermite polynomials to quantify the effects of variations in the load resistance, the eccentricity (distance between the center of mass and the elastic axis), and the nonlinear coefficients of the springs on the harvested power and the pitch and plunge amplitudes. As a first step, the normal form of the dynamics of the system near the Hopf bifurcation is used to select parameters that ensure a supercritical instability and maximize the generated power. The results show that the harvested power can be mostly affected by the eccentricity. Moreover, decreasing the nonlinear coefficient of the torsional spring results in a decrease in the pitch amplitude and an increase in the plunge amplitude and hence the harvested power. These results give guidance for optimizing and assessing the uncertainty in the performance of piezoaeroelastic energy harvesters.
The Effect of Adult HIFA Waiver Expansions on Insurance Coverage of Children
Authors: Atherly Adam , Coulam Robert F. , Dowd Bryan E. , Guy Gery
Published: March 2012

This article evaluates the effect of the Health Insurance Flexibility and Accountability (HIFA) demonstrations on uninsurance rates among children. HIFA could increase the probability that children would have health insurance either by directly enrolling a child into a HIFA program or by creating a “spillover” effect from adults onto children by making parents of children already eligible for public programs eligible for HIFA. Data were drawn from the Current Population Survey from 2000 to 2007. The estimation approach was a probit model using a difference-in-differences approach. The authors find that the HIFA wavier demonstrations had no measureable effect on the uninsurance rate among children, either through direct eligibility or through a “spillover” effect from parental eligibility. This suggests that public programs that integrate family insurance coverage into a single structure are likely to be more effective at reducing the rate of uninsurance than different programs for different members of the same family.
The Impact of the Medicaid/CHIP Expansions on Children
Authors: Howell Embry M. , Kenney Genevieve M.
Published: March 2012

This article reviews findings from 38 rigorous studies published in the peer-reviewed literature of the impact of the Medicaid/Children’s Health Insurance Program (CHIP) expansions on children. There is strong evidence for increases in enrollment in public programs and reductions in uninsurance following eligibility expansions. Medicaid enrollment continued to increase during the CHIP era (a “spillover effect”). Evidence for improved access to and use of services, particularly for dental care, is also very strong. There are fewer studies of health status impacts, and the evidence is mixed. There is a very wide range in the size of effects estimated in the studies reviewed because of the methods used and the populations studied. The review identifies several important research gaps on this topic, particularly the small number of studies of the effects on health status. Both research methods and findings from the child expansions can provide insights for evaluating the coming expansions for adults under the Affordable Care Act.
Catechol-O-Methyltransferase Gene and Executive Function in Children With ADHD
Authors: Choudhry Zia , Sengupta Sarojini , Thakur Geeta , Page Veronique , Schmitz Norbert , Grizenko Natalie , Joober Ridha
Published: March 2012

Objective: To examine the association between functional haplotypes in the catechol-o-methyltransferase (COMT) gene and ADHD diagnosis, and executive function (EF) in children with ADHD. Method: COMT single nucleotide polymorphism (SNPs; rs6269, rs4633, rs4818, and rs4680) were genotyped in 445 ADHD children. EF was assessed using Wisconsin Card Sorting Test (WCST), Tower of London, and self-ordered pointing task. COMT haplotypes were tested for association using family-based association testing (fBAT) and quantitative trait analyses. Results: fBAT analysis showed no association between COMT alleles/haplotypes and ADHD diagnosis and EF parameters. Using ANCOVA in the Caucasian only sample, significant associations between COMT haplotypes, and WCST indices were observed. However, after correction for multipletesting, the only significant effect observed was between rs6269 and the number of categories completed (a measure of concept formation ability) on the WCST, F(1,285) = 8.92, p = .003. Conclusion: These results tentatively implicate COMT gene in modulating EF in children with ADHD.
Comparison of Three ADHD Screening Instruments in College Students of Varying Cognitive Ability
Authors: Fuller-Killgore Melissa D. , Burlison Jonathan , Dwyer William
Published: March 2012

Objective: To assess three of the better known screeners for Attention Deficit/Hyperactive Disorder (ADHD) and review the relationship between ADHD and cognitive ability. Method: The three ADHD screeners were administered to 111 college students enrolled in a college Introductory Psychology class, on whom ACT scores and total course performance were also available. As a measure of cognitive ability, the Wonderlic Personnel Test (Wonderlic, Inc., 2000) was also administered. Furthermore, self-report data were available from participants who had been diagnosed with ADHD. The three screeners were the Adult ADHD Self-Report Scale (ASRS) (Kessler et al., 2005), the Conners’ Adult ADHD Rating Scale—Self-Report: Long Version (CAARS) (Conners, Erhardt, & Sparrow, 1999), and the Brown ADD Scales (Brown, 1996). Results: The results are discussed in terms of the scales’ reliability, as well as their relationship to academic aptitude, class performance, and their ability to identify self-reported ADHD diagnoses. Conclusion: All three screeners exhibited acceptable reliability levels. Criterion validity was demonstrated by the relationship between the CAARS’s inattention subscale and self-reported cases of ADHD. Criterion validity was also seen in the relationship found between the CAARS’s hyperactivity/restlessness subscale and the total course performance even after controlling for cognitive ability. Contrary to past research cognitive ability exhibited a weak but significant relationship with a few screeners and screener subscales.
Strategy Selection in ADHD Characteristics Children: A Study in Arithmetic
Authors: Sella Francesco , Re Anna Maria , Lucangeli Daniela , Cornoldi Cesare , Lemaire Patrick
Published: March 2012

Objective: It has been argued that ADHD characteristics children have difficulties in selecting the best strategy when they accomplish cognitive tasks. The detrimental influence of these poor strategy skills may be crucial for several aspects of academic achievement such as mathematical learning. Method: Fourth- and fifth-grade children with ADHD symptoms and matched controls were asked to select the better of two rounding strategies in a computational estimation task (i.e., finding the best estimate of two-digit addition problems). Results: (a) Both control and ADHD children correctly executed a selected strategy, (b) ADHD children selected the best strategy less often than controls, (c) ADHD took more time to estimate sums of two-digit addition problems and provided poorer estimates, and (d) different factors predicted best strategy selections in each group. Conclusion: These findings have important implications for further understanding the sources of differences in cognitive performance between ADHD and control children. (J. of Att. Dis. 2019; 23(1) 87-98)
Exploring the development of action research in nursing and social care in the UK: A comparative bibliometric review of action research designs in social work (2000–2010)
Authors: McVicar Andrew , Munn-Giddings Carol , Abu-Helil Christina
Published: March 2012

Action research is promoted in the UK as a vehicle for practice development in health and social care, but its application has not been evaluated. This study reviews research designs in published social work studies, 2000–2010. Applying the analytic strategy of Munn-Giddings et al. (2008) also enabled comparison to be made with nursing action research. Action research has a strong presence in social work. Studies were highly collaborative, mainly qualitative and largely focused on practice or educational development, though user-focused change had a presence. Participant groups generally were ‘active’ in the research process, but participation by academics was low. In contrast, authorship was dominated by academics. External funding suggested an attractiveness of action research to funders. Action research in social work shared similarities with nursing. Main differences were involvement of the voluntary sector, the favouring of interactive group working, and a greater likelihood of service users being co-researchers. Of most concern is the lack of authorship (and by implication, ownership) by practitioners or service users. This is contrary to the underpinning inclusive philosophy, and researchers should be more proactive in acknowledging the contribution of individuals, groups or organizations, as appropriate, and so evidence their growth in research capability and capacity.
Brain Abscesses in HIV-Positive Patients due to Pneumocystis jiroveci
Authors: Nasnas Roy , Matta Marc Y. , El Helou Gilbert , Rizk Nathalie , Sarkis Dolla Karam , Moussa Ronald
Published: March 2012

Cerebral toxoplasmosis is common in AIDS patients; however, pneumocystosis of the brain is rarely documented. We report a patient with AIDS hospitalized for brain abscesses. Stereotactic brain biopsy with immunofluorescence staining was positive for Pneumocystis jiroveci. The patient received high doses of cotrimoxazole and had a favorable clinical course.
The Stoic Male
Authors: Lehdonvirta Mika , Nagashima Yosuke , Lehdonvirta Vili , Baba Akira
Published: March 2012

Men are more reluctant to seek help for their problems than women. This difference is attributed to social expectations regarding the male gender role. Today, help-seeking is moving online: instead of traditional peer groups and counselors, people depend on online communities and e-counselors. But online users can appear in guises that differ from their physical sex. An empirical study was conducted in an online game to examine whether users’ avatars’ gender influences how they seek and receive help. Analysis is based on user-to-user communications and back-end data. Results indicate that male avatars are less likely to receive sought-for help than female avatars and more likely to be the recipients of indirectly sought help. The authors conclude that avatar gender influences help seeking independent of physical sex: Men overcome their inhibition for help seeking when using female avatars. Practitioners should ensure that means for indirect help seeking are available in order not to exclude male-pattern help seekers.
Race-Based Fantasy Realm
Authors: Monson Melissa J.
Published: March 2012

This article explores issues of racial essentialism and ethnicity in the massively multiplayer online role-playing game World of Warcraft (WoW). The fantasy world of Azeroth mirrors elements of real-world race-based societies where culture is thought to be immutably linked to race. The notion of biological essentialism is reinforced throughout the gamescape. Race plays a primary role in the social and political organization of Azeroth. Among other things, race determines alliances, language, intellect, temperament, occupation, strength, and technological aptitude. The cultural representation of the respective racial groups in WoW draws upon stereotypical imagery from real-world ethnic groups (e.g., American Indian, Irish/Scottish, Asian, African, etc.).
Restorative Magical Adventure or Warcrack? Motivated MMO Play and the Pleasures and Perils of Online Experience
Authors: Snodgrass Jeffrey G. , Dengah H. J. François , Lacy Michael G. , Fagan Jesse , Most David , Blank Michael , Howard Lahoma , Kershner Chad R. , Krambeer Gregory , Leavitt-Reynolds Alissa , Reynolds Adam , Vyvial-Larson Jessica , Whaley Josh , Wintersteen Benjamin
Published: March 2012

Combining perspectives from the new science of happiness with discussions regarding “problematic” and “addictive” play in multiplayer online games, the authors examine how player motivations pattern both positive and negative gaming experiences. Specifically, using ethnographic interviews and a survey, the authors explore the utility of Yee’s three-factor motivational framework for explaining the positive or negative quality of experiences in the popular online game World of Warcraft (2004-2012). The authors find that playing to Achieve is strongly associated with distressful play, results that support findings from other studies. By contrast, Social and Immersion play lead more typically to positive gaming experiences, conclusions diverging from those frequently reported in the literature. Overall, the authors suggest that paying attention to the positive as well as negative dimensions of inhabiting these online worlds will provide both for more balanced portraits of gamers’ experiences and also potentially clarify pathways toward problematic and addictive play.
Predictive musculoskeletal simulation using optimal control: effects of added limb mass on energy cost and kinematics of walking and running
Authors: van den Bogert Antonie J , Hupperets Maarten , Schlarb Heiko , Krabbe Berthold
Published: March 2012

When designing sports equipment, it is often desirable to predict how certain design parameters will affect human performance. In many instances, this requires a consideration of human musculoskeletal mechanics and adaptive neuromuscular control. Current computational methods do not represent these mechanisms, and design optimization typically requires several iterations of prototyping and human testing. This paper introduces a computational method based on musculoskeletal modeling and optimal control, which has the capability to predict the effect of mechanical equipment properties on human performance. The underlying assumption is that users will adapt their neuromuscular control according to an optimality principle, which balances task performance with a minimization of muscular effort. The method was applied to the prediction of metabolic cost and limb kinematics while running and walking with weights attached to the body. A two-dimensional musculoskeletal model was used, with nine kinematic degrees of freedom and 16 muscles. The optimal control problem was solved for two walking speeds and two running speeds, and at each speed, with 200 g and 400 g masses placed at the thigh, knee, shank and foot. The model predicted an increase in energy expenditure that was proportional to the added mass and the effect was largest for a mass placed on the foot. Specifically, the model predicted an energy cost increase of 0.74% for each 100 g mass added to the foot during running at 3.60 m/s. The model also predicted that stride length would increase by several millimetres in the same condition, relative to the model without added mass. These predictions were consistent with previously published human studies. Peak force and activation remained the same in most muscles, but increased by 26% in the hamstrings and by 17% in the rectus femoris for running at 4.27 m/s with 400 g added mass at the foot, suggesting muscle-specific training effects. This work demonstrated that a musculoskeletal model with optimal control can predict the effect of mechanical devices on human performance, and could become a useful tool for design optimization in sports engineering. The theoretical background of predictive simulation also helps explain why human athletes have specific responses when exercising in an altered mechanical environment.
Bone-modifying agents in the treatment of bone metastases in patients with advanced genitourinary malignancies: a focus on zoledronic acid
Authors: Aapro Matti , Saad Fred
Published: March 2012

Many patients with advanced genitourinary malignancies develop bone metastases, which can lead to potentially debilitating skeletal complications. Moreover, age-related bone loss and cancer treatments such as hormonal therapy for prostate cancer can weaken bone, placing patients at risk for osteoporotic fractures in addition to skeletal-related events (SREs) from bone metastases. Zoledronic acid, a bisphosphonate, is approved worldwide to reduce the risk of SREs in patients with bone metastases from solid tumors or bone lesions from multiple myeloma. Zoledronic acid, although underutilized in genitourinary malignancies, has long been the mainstay of treatment in patients with bone metastases, and can also help preserve bone during anticancer therapy. Recently, denosumab, a monoclonal antibody directed against the receptor activator of nuclear factor kappa-B ligand, was approved in the United States and the European Union for reducing the risk of SREs in patients with bone metastases from solid tumors. Denosumab (at a lower dose) is also approved in the European Union and the United States to treat androgen deprivation-induced bone loss in men with prostate cancer. In addition, preclinical rationale and emerging clinical data suggest that bone-modifying agents may be able to delay disease progression in genitourinary cancers, just as newly developed anticancer treatments have produced reductions in SREs, possibly by indirect effects on the disease course. This review article summarizes current data and ongoing studies to preserve bone health in patients with advanced genitourinary cancers.
Poor-prognosis estrogen receptor- positive disease: present and future clinical solutions
Authors: Lønning Per E.
Published: March 2012

Use of chemotherapy for patients with estrogen receptor (ER)-positive breast cancer has been a conflicting issue. Recent studies have identified predictive markers allowing identification of poor-prognosis ER-positive breast cancers in need of more aggressive therapy. In general, tumours belonging to the so-called luminal B class, tumours expressing a high Ki67, human epidermal growth factor receptor 2 (HER-2) overexpression or a high score on the Oncotype DX gene expression profile reveal a poor prognosis compared with ER-rich tumours of the luminal A class. In contrast, recent studies have shown these tumours, contrasting tumours of the luminal A class, to benefit from more aggressive anthracycline-containing chemotherapy including a taxane. In the case of metastatic disease, patients with HER-2-positive, ER-positive tumours may benefit from having endocrine therapy and an anti-HER-2 agent administered in combination.
Safety and efficacy of brentuximab vedotin in patients with Hodgkin lymphoma or systemic anaplastic large cell lymphoma
Authors: Vaklavas Christos , Forero-Torres Andres
Published: March 2012

Antibody-based immunotherapy has become an integral part of cancer therapeutics. However, monoclonal antibodies have their limitations as identifying an antigen selectively expressed on malignant cells and developing a high-affinity antibody may not by itself alter tumor growth. This is illustrated in the case of CD30; CD30 epitomizes many properties of an ideal pharmacologic target such as high expression on malignant cells and limited expression on normal tissues. However, until the advent of brentuximab vedotin, CD30 remained an elusive target as antibody-based anti-CD30 immunotherapy had been largely clinically unsuccessful. Brentuximab vedotin (cAC10-vcMMAE, SGN-35) is an antibody-drug conjugate consisting of a chimeric anti-CD30 monoclonal antibody whereupon the potent microtubule inhibitor monomethyl auristatin E (MMAE) is attached via a valine–citrulline linker. Once bound to CD30, brentuximab vedotin is internalized and MMAE is released with the action of lysosomal enzymes on the linker. In phase I studies in relapsed or refractory Hodgkin lymphoma and anaplastic large cell lymphoma, brentuximab vedotin induced unprecedented responses with manageable toxicity. In phase II studies, brentuximab vedotin induced overall response rates of 75% and 86% in relapsed or refractory Hodgkin lymphoma and anaplastic large cell lymphoma, respectively. The results of these trials led to the accelerated approval of the drug by the US Food and Drug Administration in a patient population with few other alternative options. Brentuximab vedotin has overall manageable toxicity profile; however, cumulative peripheral neuropathy constitutes an important clinical consideration as it may limit prolonged administration of the drug. The mechanism by which brentuximab vedotin exerts its antitumor activity is not entirely clear. Diffusion of MMAE in the tumor microenvironment and cytotoxicity on bystander cells may in part explain its activity, especially in Hodgkin lymphoma. Herein, we review the biology of CD30 and brentuximab vedotin, and the clinical data that has accumulated thus far with SGN-35.
Development of numerical simulation model for FSW employing particle method
Authors: Yoshikawa G , Miyasaka F , Hirata Y , Katayama Y , Fuse T
Published: March 2012

The friction stir welding (FSW) has been used widely in the field of industry. Numerical analysis models for FSW also have been developed and there are many papers about it. In these papers, the most frequently used method is finite element method or finite difference method. However, by employing these methods, it is difficult or troublesome to calculate the advective term both for momentum and temperature. It is also difficult to calculate the big deformation of the material. Moreover, complex process is required to analyse the dissimilar joining with respect to dealing with substance transfer. In this paper, to avoid these difficulties or troublesome processes, particle method is adopted for dissimilar FSW simulation. In particle method, advective term, substance transfer and surface deformation are calculated automatically mainly because that Lagrangian approach is used. Performing some of analysis for FSW, the effectivity of this method is verified.
Non-destructive detection of lack of penetration defects in friction stir welds
Authors: Mandache C , Levesque D , Dubourg L , Gougeon P
Published: March 2012

This study focuses on the comparative investigation of different non-destructive inspection (NDI) techniques for detecting the lack of penetration discontinuities in butt joint friction stir (FS) welds. A variably sized lack of penetration has been introduced purposely by progressively changing the tool pin's length. While inspecting the weld from the discontinuity side provides results of higher sensitivity, service inspection of the FS welded components requires evaluation of the welding tool's side, opposite the defect containing one. Non-destructive techniques amenable for inspection from either the tool side or the far side of the weld are analysed, and results from inspection are presented for comparison. Subsequently, bending tests and metallographic examinations were employed to confirm the size of the lack of penetration defects and correlate these results with the NDI capabilities.
Effect of fast cooling process on microstructure and toughness of heat affected zone in high strength pipeline steel X120
Authors: Wang H H , Wu K M , Lei X W , Qian Y
Published: March 2012

A process for improving the heat affected zone (HAZ) toughness by fast cooling during welding was developed. The holding time at high temperature above Ac3 and the cooling time from 800 to 500°C were decreased when the welding thermal cycle was experienced a fast cooling process. The microstructures in the HAZ with varied thermal cycles were examined by optical and scanning electron microscopes. The shorten holding time led to thinner HAZ width and finer austenite grains in the fusion line and coarse grained HAZ, while the decreased cooling time from 800 to 500°C resulted in finer bainitic ferrite in the HAZ. Martensite–austenite constituents in the fusion line were reduced in amount and size and predominantly changed into film-like shape. Experimental results indicated that the fast cooling process played an important role in improving the HAZ toughness of pipeline steel X120.
The miR-17-92 cluster expands multipotent hematopoietic progenitors whereas imbalanced expression of its individual oncogenic miRNAs promotes leukemia in mice
Authors: Li Yanmei , Vecchiarelli-Federico Laura M. , Li You-Jun , Egan Sean E. , Spaner David , Hough Margaret R. , Ben-David Yaacov
Published: March 2012

The miR-17-92 cluster and its 6 encoded miRNAs are frequently amplified and aberrantly expressed in various malignancies. This study demonstrates that retroviral-mediated miR-17-92 overexpression promotes expansion of multipotent hematopoietic progenitors in mice. Cell lines derived from these miR-17-92–overexpressing mice are capable of myeloid and lymphoid lineage differentiation, and recapitulate the normal lymphoid phenotype when transplanted to nonobese diabetic/severe combined immunodeficiency mice. However, overexpression of individual miRNAs from this locus, miR-19a or miR-92a, results in B-cell hyperplasia and erythroleukemia, respectively. Coexpression of another member of this cluster miR-17, with miR-92a, abrogates miR-92a–induced erythroleukemogenesis. Accordingly, we identified several novel miR-92a and miR-17 target genes regulating erythroid survival and proliferation, including p53. Expression of this critical target results in marked growth inhibition of miR-92a erythroleukemic cells. In both murine and human leukemias, p53 inactivation contributed to the selective overexpression of oncogenic miR-92a and miR-19a, and down-regulation of tumor-suppressive miR-17. This miR-17-92 expression signature was also detected in p53− B-cell chronic lymphocytic leukemia patients displaying an aggressive clinical phenotype. These results revealed that imbalanced miR-17-92 expression, also mediated by p53, directly transforms the hematopoietic compartment. Thus examination of such miRNA expression signatures should aid in the diagnosis and treatment of cancers displaying miR-17-92 gene amplification.
Progression in smoldering Waldenström macroglobulinemia: long-term results
Authors: Kyle Robert A. , Benson Joanne T. , Larson Dirk R. , Therneau Terry M. , Dispenzieri Angela , Kumar Shaji , Melton L. Joseph , Rajkumar S. Vincent
Published: March 2012

The purpose of this study was to define the risk of progression and survival of patients with smoldering Waldenström macroglobulinemia (SWM). SWM is defined clinically as having a serum monoclonal IgM protein ≥ 3 g/dL and/or ≥ 10% bone marrow lymphoplasmacytic infiltration but no evidence of end-organ damage (anemia, constitutional symptoms, hyperviscosity, lymphadenopathy, or hepatosplenomegaly). We searched a computerized database and reviewed the medical records of all patients at Mayo Clinic who fulfilled the criteria of SWM between 1974 and 1995. During 285 cumulative person-years of follow-up of the 48 patients with SWM (median, 15.4 years), 34 (71%) progressed to symptomatic Waldenström macroglobulinemia (WM) requiring treatment, one to primary amyloidosis, and one to lymphoma (total, 75%). The cumulative probability of progression to symptomatic WM, amyloidosis, or lymphoma was 6% at 1 year, 39% at 3 years, 59% at 5 years, and 68% at 10 years. The major risk factors for progression were percentage of lymphoplasmacytic cells in the bone marrow, size of the serum M-spike, and the hemoglobin value. Patients with SWM should be followed and not treated until symptomatic WM develops. Treatment on a clinical trial for those at greatest risk of progression should be considered.
Distinct mutations in STXBP2 are associated with variable clinical presentations in patients with familial hemophagocytic lymphohistiocytosis type 5 (FHL5)
Authors: Pagel Julia , Beutel Karin , Lehmberg Kai , Koch Florian , Maul-Pavicic Andrea , Rohlfs Anna-Katharina , Al-Jefri Abdullah , Beier Rita , Bomme Ousager Lilian , Ehlert Karoline , Gross-Wieltsch Ute , Jorch Norbert , Kremens Bernhard , Pekrun Arnulf , Sparber-Sauer Monika , Mejstrikova Ester , Wawer Angela , Ehl Stephan , zur Stadt Udo , Janka Gritta
Published: March 2012

Familial hemophagocytic lymphohistiocytosis (FHL) is a genetically determined hyperinflammatory syndrome caused by uncontrolled immune response mediated by T-lymphocytes, natural killer (NK) cells, and macrophages. STXBP2 mutations have recently been associated with FHL5. To better characterize the genetic and clinical spectrum of FHL5, we analyzed a cohort of 185 patients with suspected FHL for mutations in STXBP2. We detected biallelic mutations in 37 patients from 28 families of various ethnic origins. Missense mutations and mutations affecting 1 of the exon 15 splice sites were the predominant changes detectable in this cohort. Patients with exon 15 splice-site mutations (n = 13) developed clinical manifestations significantly later than patients with other mutations (median age, 4.1 year vs 2 months) and showed less severe impairment of degranulation and cytotoxic function of NK cells and CTLs. Patients with FHL5 showed several atypical features, including sensorineural hearing deficit, abnormal bleeding, and, most frequently, severe diarrhea that was only present in early-onset disease. In conclusion, we report the largest cohort of patients with FHL5 so far, describe an extended disease spectrum, and demonstrate for the first time a clear genotype-phenotype correlation.
Drug response in a genetically engineered mouse model of multiple myeloma is predictive of clinical efficacy
Authors: Chesi Marta , Matthews Geoffrey M. , Garbitt Victoria M. , Palmer Stephen E. , Shortt Jake , Lefebure Marcus , Stewart A. Keith , Johnstone Ricky W. , Bergsagel P. Leif
Published: March 2012

The attrition rate for anticancer drugs entering clinical trials is unacceptably high. For multiple myeloma (MM), we postulate that this is because of preclinical models that overemphasize the antiproliferative activity of drugs, and clinical trials performed in refractory end-stage patients. We validate the Vk*MYC transgenic mouse as a faithful model to predict single-agent drug activity in MM with a positive predictive value of 67% (4 of 6) for clinical activity, and a negative predictive value of 86% (6 of 7) for clinical inactivity. We identify 4 novel agents that should be prioritized for evaluation in clinical trials. Transplantation of Vk*MYC tumor cells into congenic mice selected for a more aggressive disease that models end-stage drug-resistant MM and responds only to combinations of drugs with single-agent activity in untreated Vk*MYC MM. We predict that combinations of standard agents, histone deacetylase inhibitors, bromodomain inhibitors, and hypoxia-activated prodrugs will demonstrate efficacy in the treatment of relapsed MM.