bluuebunny/crossref_metadata_2025 huggingface dataset:
Racial and ethnic variation in home healthcare nurse depression assessment of older minority patients
Authors: Pickett Yolonda R. , Bazelais Kisha N. , Greenberg Rebecca L. , Bruce Martha L.
Published: November 2013

Objective

The objective of this study is to determine the racial/ethnic effect of depression symptom recognition by home healthcare nurses.

Methods

This is a secondary analysis of administrative data from a large urban home healthcare agency. Patients' age were 65 years and older with a valid depression screen, identified as Caucasian, African American, or Hispanic and admitted to homecare in 2010 (N = 3711). All demographic and clinical information were obtained from the electronic medical record.

Results

Subjects were 29.34% Caucasian, 37.81% African American, and 32.85% Hispanic. About 6.52% had a formal chart diagnosis of depression, and 13.39% received antidepressant therapy. The rates of positive depression screens by nurses were higher in Caucasians than that of in African Americans or Hispanics (13.41% vs. 9.27% vs. 10.99%; χ2 = 10.70, df [degrees of freedom] = 2; p < 0.01). Depression screening rates were then stratified by the number of clinical indicators from the chart (depression diagnosis or antidepressant on medication list). The proportion of positive screen increased for minorities with an increase in the number of indicators. African Americans had significantly greater positive screens with two indicators compared with that of the Caucasians and Hispanics (50.00% vs. 23.81% vs. 35.59%; χ2 = 6.65, df = 2; p = 0.04).

Conclusions

These findings show a wide range of variation in screening for depression among ethnic groups. The rates increase for minorities with the presence of increased clinical indicators, suggesting that nurses may screen higher in minorities when there is higher clinical suspicion. Future research in home healthcare should be aimed at training nurses to conduct culturally tailored depression screening to improve management of depression in older minorities. Copyright © 2013 John Wiley & Sons, Ltd.
Differential effects of sorafenib on liver versus tumor fibrosis mediated by stromal-derived factor 1 alpha/C-X-C receptor type 4 axis and myeloid differentiation antigen–positive myeloid cell infiltration in mice
Authors: Chen Yunching , Huang Yuhui , Reiberger Thomas , Duyverman Annique M. , Huang Peigen , Samuel Rekha , Hiddingh Lotte , Roberge Sylvie , Koppel Christina , Lauwers Gregory Y. , Zhu Andrew X. , Jain Rakesh K. , Duda Dan G.
Published: November 2013

Sorafenib—a broad kinase inhibitor—is a standard therapy for advanced hepatocellular carcinoma (HCC) and has been shown to exert antifibrotic effects in liver cirrhosis, a precursor of HCC. However, the effects of sorafenib on tumor desmoplasia—and its consequences on treatment resistance—remain unknown. We demonstrate that sorafenib has differential effects on tumor fibrosis versus liver fibrosis in orthotopic models of HCC in mice. Sorafenib intensifies tumor hypoxia, which increases stromal-derived factor 1 alpha (SDF-1α) expression in cancer and stromal cells and, subsequently, myeloid differentiation antigen–positive (Gr-1+) myeloid cell infiltration. The SDF-1α/C-X-C receptor type 4 (CXCR4) pathway directly promotes hepatic stellate cell (HSC) differentiation and activation through the mitogen-activated protein kinase pathway. This is consistent with the association between SDF-1α expression with fibrotic septa in cirrhotic liver tissues as well as with desmoplastic regions of human HCC samples. We demonstrate that after treatment with sorafenib, SDF-1α increased the survival of HSCs and their alpha-smooth muscle actin and collagen I expression, thus increasing tumor fibrosis. Finally, we show that Gr-1+ myeloid cells mediate HSC differentiation and activation in a paracrine manner. CXCR4 inhibition, using AMD3100 in combination with sorafenib treatment, prevents the increase in tumor fibrosis—despite persistently elevated hypoxia—in part by reducing Gr-1+ myeloid cell infiltration and inhibits HCC growth. Similarly, antibody blockade of Gr-1 reduces tumor fibrosis and inhibits HCC growth when combined with sorafenib treatment. Conclusion: Blocking SDF-1α/CXCR4 or Gr-1+ myeloid cell infiltration may reduce hypoxia-mediated HCC desmoplasia and increase the efficacy of sorafenib treatment. (HEPATOLOGY 2014;59:1435-1447)
One‐Pot Synthesis of Dispiro[oxindole‐3,3′‐pyrrolidines] by Three‐Component [3+2] Cycloadditions of in situ‐Generated Azomethine Ylides with 3‐Benzylidene‐2,3‐dihydro‐1H‐indol‐2‐ones
Authors: Matloubi Moghaddam Firouz , Kiamehr Mostafa , Reza Khodabakhshi Mohammad , Jebeli Javan Marjan , Fathi Shaghayegh , Villinger Alexander , Iaroshenko Viktor O. , Langer Peter
Published: November 2013

An efficient one‐pot, three‐component synthesis of novel dispiro[oxindole‐3,3′‐pyrrolidines] by 1,3‐dipolar cycloaddition of azomethine ylides, in situ generated by reaction of 1,2‐diones with sarcosine and subsequent decarboxylation, with a series of (E)‐3‐benzylidene‐2,3‐dihydro‐1H‐indol‐2‐ones is reported. Molecular complexity is generated in only one synthetic step. All reactions proceed with excellent regioselectivity and in good‐to‐excellent yields. The workup is easy, the reaction times are short, and no catalyst is required.
Stereoselective Total Synthesis of 4‐Ketoclonostachydiol
Authors: Rajaram Singanaboina , Ramulu Udugu , Ramesh Dasari , Prabhakar Peddikotla , Venkateswarlu Yenamandra
Published: November 2013

An efficient stereoselective total synthesis of the bioactive 14‐membered natural macrocyclic bislactone 4‐ketoclonostachydiol is described. The strategy involves a Jacobsen's hydrolytic kinetic resolution (HKR), epoxide opening, MacMillan α‐hydroxylation, HornerWadsworthEmmons olefination, a Grignard reaction, and HoveydaGrubbs‐II‐catalyzed ring‐closing metathesis (RCM) as key steps.
Maspin influences response to doxorubicin by changing the tumor microenvironment organization
Authors: Triulzi Tiziana , Ratti Manuela , Tortoreto Monica , Ghirelli Cristina , Aiello Piera , Regondi Viola , Di Modica Martina , Cominetti Denis , Carcangiu Maria L. , Moliterni Angela , Balsari Andrea , Casalini Patrizia , Tagliabue Elda
Published: November 2013

Altered degradation and deposition of extracellular matrix are hallmarks of tumor progression and response to therapy. From a microarray supervised analysis on a dataset of chemotherapy‐treated breast carcinoma patients, maspin, a member of the serpin protease inhibitor family, has been the foremost variable identified in non‐responsive versus responsive tumors. Accordingly, in a series of 52 human breast carcinomas, we detected high maspin expression in tumors that progressed under doxorubicin (DXR)‐based chemotherapy. Our analysis of the role of maspin in response to chemotherapy in human MCF7 and MDAMB231 breast and SKOV3 ovarian carcinoma cells transfected to overexpress maspin and injected into mice showed that maspin overexpression led to DXR resistance through the maspin‐induced collagen‐enriched microenvironment and that an anti‐maspin neutralizing monoclonal antibody reversed the collagen‐dependent DXR resistance. Impaired diffusion and decreased DXR activity were also found in tumors derived from Matrigel‐embedded cells, where abundant collagen fibers characterize the tumor matrix. Conversely, liposome‐based DXR reached maspin‐overexpressing tumor cells despite the abundant extracellular matrix and was more efficient in reducing tumor growth. Our results identify maspin‐induced accumulation of collagen fibers as a cause of disease progression under DXR chemotherapy for breast cancer. Use of a more hydrophilic DXR formulation or of a maspin inhibitor in combination with chemotherapy holds the promise of more consistent responses to maspin‐overexpressing tumors and dense‐matrix tumors in general.
Dietary nitrate and nitrite intake and risk of colorectal cancer in the Shanghai Women's Health Study
Authors: DellaValle Curt T. , Xiao Qian , Yang Gong , Shu Xiao-Ou , Aschebrook‐Kilfoy Briseis , Zheng Wei , Lan Li Hong , Ji Bu‐Tian , Rothman Nathaniel , Chow Wong‐Ho , Gao Yu‐Tang , Ward Mary H.
Published: November 2013

Nitrate and nitrite are precursors of endogenously formed N‐nitroso compounds (NOC), known animal carcinogens. Nitrosation reactions forming NOCs can be inhibited by vitamin C and other antioxidants. We prospectively investigated the association between dietary nitrate and nitrite intake and risk of colorectal cancer in the Shanghai Women's Health Study, a cohort of 73,118 women ages 40–70 residing in Shanghai. We evaluated effect modification by factors that affect endogenous formation of NOCs: vitamin C (at or above/below median) and red meat intake (at or above/below median). Nitrate, nitrite and other dietary intakes were estimated from a 77‐item food frequency questionnaire administered at baseline. Over a mean of 11 years of follow‐up, we identified 619 colorectal cancer cases (n = 383, colon; n = 236, rectum). Hazard ratios (HR) and 95% confidence intervals (CI) were estimated using Cox proportional hazard regression. Overall, nitrate intake was not associated with colorectal cancer risk (HR = 1.08; 95% CI: 0.73–1.59). However, among women with vitamin C intake below the median (83.9 mg day−1) and hence higher potential exposure to NOCs, risk of colorectal cancer increased with increasing quintiles of nitrate intake (highest vs. lowest quintile HR = 2.45; 95% CI: 1.15–5.18; p trend = 0.02). There was no association among women with higher vitamin C intake. We found no association between nitrite intake and risk of colorectal cancer overall or by intake level of vitamin C. Our findings suggest that high dietary nitrate intake among subgroups expected to have higher exposure to endogenously formed NOCs increases risk of colorectal cancer.
Increased methylmercury toxicity related to obesity in diabetic KK‐Ay mice
Authors: Yamamoto Megumi , Yanagisawa Rie , Motomura Eriko , Nakamura Masaaki , Sakamoto Mineshi , Takeya Motohiro , Eto Komyo
Published: November 2013

We examined the toxic effects of methylmercury (MeHg) in KK‐Ay type 2 diabetic mice to clarify how metabolic changes associated with type 2 diabetes mellitus affect MeHg toxicity. MeHg (5 mg Hg kg –1day–1 p.o.) was given to 4‐week‐old male KK‐Ay and C57BL/6J (BL/6) mice three times per week for 6 weeks. Average body weights (BW) of vehicle‐treated BL/6 and KK‐Ay mice were 16.3 and 16.4 g respectively on the first day, and 24.8 and 42.3 g respectively on the last day of the experiment. MeHg‐treated KK‐Ay mice began to lose weight about 5 weeks after MeHg administration. Six of seven MeHg‐treated KK‐Ay mice showed hind‐limb clasping in the final stage of the experiment. The mean blood mercury level of MeHg‐treated KK‐Ay mice reached a maximum of 9.8 µg ml–1, whereas that of the MeHg‐treated BL/6 mice was 2.8 µg ml–1 after 10 days of treatment. The average total mercury concentrations in the cerebrum and epididymal fat pad were 7.4 and 0.57 µg g–1, respectively, for BL/6 mice and 27 and 1.6 µg g–1, respectively, for KK‐Ay mice. In MeHg‐treated KK‐Ay mice with neurological symptoms, CD204‐positive macrophages were observed in the brain, kidney and spleen, indicating CD204 could be a marker for injured tissues. BW loss and significant pathological changes were not observed in other groups of mice. These results indicate that body fat gain in type 2 diabetes mellitus and low mercury accumulation in adipose tissue increased MeHg concentrations in organs and enhanced toxicity in KK‐Ay mice at the same dose of MeHg per BW. Copyright © 2013 John Wiley & Sons, Ltd.
Major Osteoporotic to Hip Fracture Ratios in Canadian Men and Women With Swedish Comparisons: A Population-Based Analysis
Authors: Lam Anna , Leslie William D , Lix Lisa M , Yogendran Marina , Morin Suzanne N , Majumdar Sumit R
Published: November 2013

Fracture Risk Assessment (FRAX) tools are calibrated from country-specific fracture epidemiology. Although hip fracture data are usually available, data on non-hip fractures for most countries are often lacking. In such cases, rates are often estimated by assuming similar non-hip to hip fracture ratios from historical (1987 to 1996) Swedish data. Evidence that countries share similar fracture ratios is limited. Using data from Manitoba, Canada (2000 to 2007, population 1.2 million), we identified 21,850 incident major osteoporotic fractures (MOF) in men and women aged >50 years. Population-based age- and sex-specific ratios of clinical vertebral, forearm, and humerus fractures to hip fractures were calculated, along with odds ratios (ORs) and 95% confidence intervals (CIs). All ratios showed decreasing trends with increasing age for both men and women. Men and women showed similar vertebral/hip fracture ratios (all p > 0.1, with ORs 0.86 to 1.25). Forearm/hip and humerus/hip fracture ratios were significantly lower among men than women (forearm/hip ratio: p < 0.01 for all age groups, with ORs 0.29 to 0.53; humerus/hip ratio: p < 0.05 for all age groups [except 80 to 84 years] with ORs 0.46 to 0.86). Ratios for any MOF/hip fracture were also significantly lower among men than women in all but two subgroups (p < 0.05 for all age groups [except 80 to 84 and 90+ years] with ORs 0.48 to 0.87). Swedish vertebral/hip fracture ratios were similar to the Canadian fracture ratios (within 7%) but significantly lower for other sites (men and women: 46% and 35% lower for forearm/hip ratios, 19% and 15% lower for humerus/hip ratios, and 19% and 23% lower for any MOF/hip ratios). These differences have implications for updating and calibrating FRAX tools, fracture risk estimation, and intervention rates. Moreover, wherever possible, it is important that countries try to collect accurate non-hip fracture data. © 2014 American Society for Bone and Mineral Research
FAIRTRADE: COMMENT ON TEDESCHI AND CARLSON
Authors: Griffiths Peter
Published: November 2013

In a recent issue of this journal, Tedeschi and Carlson presented far reaching conclusions on the impact of fair trade. They reject the conclusions of others on the grounds that they are based on incorrect assumptions. It is argued here that their own assumptions are false, seriously misrepresenting fair trade or Fairtrade. Their analysis is therefore incorrect, and their models must be rejected in their entirety. Copyright © 2013 John Wiley & Sons, Ltd.
Perfusion measurements of the calf in patients with peripheral arterial occlusive disease before and after percutaneous transluminal angioplasty using Mr arterial spin labeling
Authors: Grözinger Gerd , Pohmann Rolf , Schick Fritz , Grosse Ulrich , Syha Roland , Brechtel Klaus , Rittig Kilian , Martirosian Petros
Published: November 2013

Purpose

To evaluate muscle perfusion in patients with peripheral arterial occlusive disease (PAOD) before and after percutaneous transluminal angioplasty (PTA) of the limb by means of MR arterial spin labeling (ASL) perfusion measurements during reactive hyperemia.

Materials and Methods

Ten patients with symptomatic PAOD affecting the iliac or femoral vessels were investigated before and after PTA. A pseudo‐continuous arterial spin labeling (PCASL) MR technique was applied. Perfusion was measured in soleus and tibialis anterior muscle during reactive hyperemia. Key parameters such as mean perfusion value (Phyp), time‐to‐peak (TTP) and duration of hyperemia (Thyp) describing the perfusion signal curve were examined.

Results

Between baseline and post‐PTA, Phyp increased in both muscle groups. At the same time, TTP and Thyp decreased in both muscle groups. At the same time the clinically assessed ankle brachial index (ABI) increased from 0.56 ± 0.10 to 0.83 ± 0.15. The impaired pain‐free walking distance improved in all patients.

Conclusion

PCASL MRI can detect changes of the key perfusion parameters Phyp, TTP, and Thyp after successful PTA of the calf muscles during reactive hyperemia and seems to be a promising tool for monitoring of interventional treatments. J. Magn. Reson. Imaging 2014;40:980–987. © 2013 Wiley Periodicals, Inc.
Rapid single‐breath‐hold 3D late gadolinium enhancement cardiac MRI using a stack‐of‐spirals acquisition
Authors: Shin Taehoon , Lustig Michael , Nishimura Dwight G. , Hu Bob S.
Published: November 2013

Purpose

To develop a rapid single‐breath‐hold 3D late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) method, and demonstrate its feasibility in cardiac patients.

Materials and Methods

An inversion recovery dual‐density 3D stack‐of‐spirals imaging sequence was developed. The spiral acquisition was 2‐fold accelerated by self‐consistent parallel imaging reconstruction (SPIRiT), which resulted in a total scan time of 12 heartbeats. Field map‐based linear off‐resonance correction was incorporated to the SPIRiT reconstruction. The 3D spiral LGE scans were performed in 15 patients who were referred for clinically ordered cardiac MR examinations that included the standard 2D multislice LGE imaging. Image sharpness and overall quality were qualitatively assessed based on 5‐point scales.

Results

Scar‐induced hyper‐LGE was identified in 4 out of the 15 patients by both 3D spiral and 2D multislice LGE tests. On average over all datasets (n = 15), the image sharpness scores were 3.9 (3D spiral) and 4.0 (2D multislice), and the image quality scores were 4.1 (3D spiral) and 4.0 (2D multislice) with no significant difference in both metrics (paired t‐test; P > 0.1). The average scar contrast enhancement ratios were 0.72 and 0.75 in 3D and 2D images, respectively (n = 4). The average difference of fractional scar volumes measured in 3D and 2D images was 4.3% (n = 3).

Conclusion

Stack‐of‐spiral acquisition combined with non‐Cartesian SPIRiT parallel imaging enables rapid 3D LGE MRI in a 12 heartbeat‐long breath‐hold.J. Magn. Reson. Imaging 2014;40:1496–1502. © 2013 Wiley Periodicals, Inc.
MR lymphangiography at 3.0 tesla to assess the function of inguinal lymph node in low extremity lymphedema
Authors: Zhou Guo‐xing , Chen Xiao , Zhang Jian‐hua , Zhu Jing‐qi , Wang Yi‐bin , Wang Zhong‐qiu
Published: November 2013

Purpose

To assess the function of inguinal lymph node (ILN) in low extremity lymphedema (LEL) with dynamic enhanced MR lymphangiography (MRL).

Materials and Methods

Sixty‐four patients with clinically diagnosed LEL underwent MRL examinations. The lymph drainage patterns were separated into four subtypes. The peak time to enhancement and the contrast ratio of the ILN were calculated 35 min following contrast agent administration.

Results

Dilated lymphatic vessels could be observed in all subjects. Type I–IV drainage patterns were observed 25% (16/64), 45.31% (29/64), 17.19% (11/64), and 12.5% (8/64), respectively. The ILN in the edematous limbs could be observed in 93.75% (60/64) of subjects. The peak time to enhancement was correlated with clinical stages (P < 0.001) of the disease, lymph drainage patterns (P < 0.001), and the duration of lymphedema (P < 0.001). The contrast ratios were significantly different at each time point (P < 0.001) and significantly correlated with the lymphatic drainage patterns (P < 0.001).

Conclusion

MRL could provide useful information for evaluating the functional status of the ILN. Data presented here demonstrate that the functionality of the ILN is related to the clinical stage of the disease, lymphatic drainage patterns, and the duration of lymphedema.J. Magn. Reson. Imaging 2014;40:1430–1436. © 2013 Wiley Periodicals, Inc.
Posttraumatic Responses to the July 22, 2011 Oslo Terror Among Norwegian High School Students
Authors: Nordanger Dag Ø. , Hysing Mari , Posserud Maj‐Britt , Lundervold Astri Johansen , Jakobsen Reidar , Olff Miranda , Stormark Kjell Morten
Published: November 2013

The July 22, 2011, Oslo Terror was defined as a national disaster. Former studies on terror attacks and mass shootings have shown elevated levels of posttraumatic complaints both in direct victims and in general populations. Little is known about how such extreme events in a generally safe society such as Norway would affect an adolescent population. This study examines posttraumatic stress reactions and changes in worldview in relationship to risk factors among 10,220 high school students using data from the ung@hordaland survey. One out of 5 respondents knew someone directly exposed, 55.7% experienced the events to some extent as threatening to their own or their close ones’ lives, and 79.9% reported their worldview to be changed. For posttraumatic stress disorder (PTSD) DSM IV criteria, 0.8% reported substantial symptoms of reexperiencing (Criterion B), 4.9% of avoidance (Criterion C), and 1.1% of hyperarousal (Criterion D). Greater personal proximity to the events, higher levels of perceived life threat, and being a female or an immigrant predicted higher levels of PTSD symptom distress. Results indicate that the terror events made a deep impression on Norwegian adolescents, but without causing markedly elevated levels of PTSD symptomatology in the general young population.
Maltreatment Is Associated With Specific Impairments in Executive Functions: A Pilot Study
Authors: Augusti Else‐Marie , Melinder Annika
Published: November 2013

Child maltreatment is associated with a host of adverse consequences. Few studies exist that map maltreated children's performance on neurocognitive tests particularly sensitive to brain and behavior associations. The aim of the present study was to investigate whether maltreated children differed in their executive functioning compared to their nonmaltreated peers, and if they did so in specific ways. Tasks aimed at measuring set shifting, spatial working memory, and inhibition were administered. Trauma‐related symptomatology was further assessed to study the potential effect of maltreatment‐related psychopathology on executive functioning. A univariate analysis of variance showed that maltreated children (n = 21) performed significantly poorer compared to their nonmaltreated peers (n = 22) on the Spatial Working Memory task. Symptoms of trauma‐related psychopathology were not associated with performance on the executive functions tests. In conclusion, maltreatment was not associated with a global deficit in children's executive functions. Thus, when considering maltreated children's cognitive functioning, specific measures of executive functions should be applied.
Intimate Partner Violence Among Women Veterans: Previous Interpersonal Violence as a Risk Factor
Authors: Iverson Katherine M. , Mercado Rowena , Carpenter Sarah L. , Street Amy E.
Published: November 2013

Experiences of abuse during childhood or military service may increase women veterans’ risk for intimate partner violence (IPV) victimization. This study examined the relative impact of 3 forms of interpersonal violence exposure (childhood physical abuse [CPA], childhood sexual abuse [CSA], and unwanted sexual experiences during military service) and demographic and military characteristics on past‐year IPV among women veterans. Participants were 160 female veteran patients at Veterans Afffairs hospitals in New England who completed a paper‐and‐pencil mail survey that included validated assessments of past‐year IPV and previous interpersonal violence exposures. Women who reported CSA were 3.06 times, 95% confidence interval (CI) [1.14, 8.23], more likely to report past‐year IPV relative to women who did not experience CSA. Similarly, women who reported unwanted sexual experiences during military service were 2.33 times, 95% CI [1.02, 5.35], more likely to report past‐year IPV compared to women who did not report such experiences. CPA was not associated with IPV risk. Having less education and having served in the Army (vs. other branches) were also associated with greater risk of experiencing IPV in the past year. Findings have implications for assisting at risk women veterans in reducing their risk for IPV through detection and intervention efforts.
Comparing Response to Cognitive Processing Therapy in Military Veterans With Subthreshold and Threshold Posttraumatic Stress Disorder
Authors: Dickstein Benjamin D. , Walter Kristen H. , Schumm Jeremiah A. , Chard Kathleen M.
Published: November 2013

Research suggests that subthreshold posttraumatic stress disorder (PTSD) symptomatology is associated with increased risk for psychological and functional impairment, including increased risk for suicidal ideation. However, it does not appear that any studies to date have investigated whether subthreshold PTSD can effectively be treated with evidence‐based, trauma‐focused treatment. Accordingly, we tested response to cognitive processing therapy (CPT) in 2 groups of military veterans receiving care at a VA outpatient specialty clinic, 1 with subthreshold PTSD at pretreatment (n = 51) and the other with full, diagnostic PTSD (n = 483). Multilevel analysis revealed that both groups experienced a significant decrease in PTSD symptoms over the course of therapy (the full and subthreshold PTSD groups experienced an average decrease of 1.79 and 1.52 points, respectively, on the PTSD Checklist with each increment of time, which was coded from 0 at pretreatment to 13 at posttreatment). After controlling for pretreatment symptom severity, a between‐groups difference was not found. These results suggest that CPT is an effective form of treatment among military veterans, and that its effectiveness does not differ between subthreshold and threshold groups.
Electrostatically Driven Complexation of Liposomes with a Star‐Shaped Polyelectrolyte to Low‐Toxicity Multi‐Liposomal Assemblies
Authors: Yaroslavov Alexander A. , Sybachin Andrey V. , Zaborova Olga V. , Pergushov Dmitry V. , Zezin Alexander B. , Melik‐Nubarov Nikolay S. , Plamper Felix A. , Müller Axel H. E. , Menger Frederic M.
Published: November 2013

Anionic liposomes are electrostatically complexed to a star‐shaped cationic polyelectrolyte. Upon complexation, the liposomes retain their integrity and the resulting liposome‐star complexes do not dissociate in a physiological solution with 0.15 M NaCl. This provides a multi‐liposomal container for possible use as a high‐capacity carrier.
The value of putaminal diffusion imaging versus 18‐fluorodeoxyglucose positron emission tomography for the differential diagnosis of the Parkinson variant of multiple system atrophy
Authors: Baudrexel Simon , Seifried Carola , Penndorf Bianca , Klein Johannes C. , Middendorp Marcus , Steinmetz Helmuth , Grünwald Frank , Hilker Rüdiger
Published: November 2013

Differentiating the Parkinson variant of multiple system atrophy (MSA‐P) from idiopathic Parkinson's disease (PD) and other forms of atypical parkinsonism can be difficult because symptoms overlap considerably. 18‐Fluorodeoxyglucose positron emission tomography (FDG‐PET) is a powerful imaging technique that can assist in the diagnosis of MSA‐P via detection of putaminal and cerebellar hypometabolism. Recent studies suggest that diffusion‐weighted imaging (DWI) might be of similar diagnostic value, as it can detect microstructural damage in the putamen by means of an increased mean diffusivity (MD). The aim of this study was a direct comparison of DWI and FDG‐PET by using both methods on the same subject cohort. To this end, combined DWI and FDG‐PET were employed in patients with MSA‐P (n = 11), PD (n = 13), progressive supranuclear palsy (n = 8), and in 6 control subjects. MD values and FDG uptake ratios were derived from volumetric parcellations of the putamen and subjected to further analysis of covariance (ANCOVA) and receiver operating characteristics analyses. MSA‐P was found to be associated with an increased posterior putaminal MD (P < 0.001 in all subgroup comparisons) that correlated strongly with local reductions in FDG uptake (r = −0.85, P = 0.002). DWI discriminated patients with MSA‐P from other subgroups nearly as accurately as FDG‐PET (area under the curve = 0.89 vs 0.95, P = 0.27 [pooled data]). Our data suggest a close association between the amount of putaminal microstructural damage and a reduced energy metabolism in patients with MSA‐P. The clinical use of DWI for the differential diagnosis of MSA‐P is encouraged. © 2013 International Parkinson and Movement Disorder Society
Relative distance between two scalar fields. Application to mathematical modelling approximation
Authors: González‐Santander Juan L. , González Germán Martín
Published: November 2013

Inspired in the relative error between two quantities, we define a functional ΔD that operates on two non‐negative scalar fields, which are integrable in a given open connected set D. We prove that ΔD defines a metric, but not an ultrametric nor a translation invariant metric. We show how to apply ΔD to evaluate the performance of analytical approximations of PDEs. The principal advantage of using ΔD instead of other distances given in the literature is that the value given by ΔD has a very easy interpretation: a value close to 0 means relatively near, but a value close to 1 means relatively infinitely far. Copyright © 2013 John Wiley & Sons, Ltd.
Discrete mass conservation for porous media saturated flow
Authors: Jenkins Eleanor W. , Paribello Chris , Wilson Nicholas E.
Published: November 2013

Global and local mass conservation for velocity fields associated with saturated porous media flow have long been recognized as integral components of any numerical scheme attempting to simulate these flows. In this work, we study finite element discretizations for saturated porous media flow that use Taylor–Hood (TH) and Scott–Vogelius (SV) finite elements. The governing equations are modified to include a stabilization term when using the TH elements, and we provide a theoretical result that shows convergence (with respect to the stabilization parameter) to pointwise mass‐conservative solutions. We also provide results using the SV approximation pair. These elements are pointwise divergence free, leading to optimal convergence rates and numerical solutions. We give numerical results to verify our theory and a comparison with standard mixed methods for saturated flow problems. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 625–640, 2014
BEHAVIOR MANAGEMENT IN PRESCHOOL CLASSROOMS: INSIGHTS REVEALED THROUGH SYSTEMATIC OBSERVATION AND INTERVIEW
Authors: Ritz Mariah , Noltemeyer Amity , Davis Darrel , Green Jennifer
Published: November 2013

This mixed methods study examined behavior management strategies used by preschool teachers to address student noncompliance in the classroom. Specifically, the study aimed to (1) examine the methods that preschool teachers are currently using to respond to noncompliant behavior in their classrooms, (2) measure the frequency with which each strategy is used or attempted, and (3) examine the reasons that teachers have chosen to use particular strategies. Observations and teacher interviews were conducted in five classrooms across two preschools located in a Midwest state. Results revealed that teachers use a variety of strategies to address noncompliance, many of which were also preventative in nature and designed to increase students’ self‐regulation. In addition, behavior management techniques that are currently recommended by research (e.g., guided compliance and proximity praise) were generally practiced by teachers in the participating schools. However, students were reinforced for appropriate behavior following noncompliance less than one‐third of the time. These results suggest that teachers are using a broad range of recommended strategies, but the results also serve as a reminder of the importance of providing positive reinforcement for appropriate behavior following an episode of noncompliance. Additional implications for school practitioners and future research are provided.
Light‐directed mesoscale phase separation via holographic polymerization
Authors: Smith Derrick M. , Li Christopher Y. , Bunning Timothy J.
Published: November 2013

Holographic polymerization (HP) is a simple, fast, and attractive technique to fabricate one‐, two‐ and three‐dimensional complex and functional nanostructures. Not only does the coupling of photopolymerization and light‐directed phase separation HP process render rich polymer physics to the latter, it also leads to profound morphology‐sensitive properties of HP structures, ranging from nano‐ to mesoscales. The past two decades witnessed tremendous progress in the field and in this review, we will probe the fundamental characteristics and parameters of HP, exemplify the versatility of this nanofabrication technique by presenting a diverse selection of HP patterned soft materials, and discuss some unique applications of such HP structures. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 232–250
Effects of emotion regulation and general self‐efficacy on posttraumatic growth in Chinese cancer survivors: assessing the mediating effect of positive affect
Authors: Yu Yongju , Peng Li , Tang Tang , Chen Long , Li Min , Wang Tao
Published: November 2013

Background

In recent years, there have been increasing concerns about the existence of posttraumatic growth as a result of the struggle with cancer. The present study examined several potential predictors of posttraumatic growth and the mediating role of positive affect among Chinese cancer survivors.

Methods

Two hundred thirty cancer survivors recruited from two Chinese hospitals completed self‐report measures of perceived posttraumatic growth, emotion regulation, positive and negative affect, and general self‐efficacy. Correlation analysis, hierarchical linear regression analysis, and Sobel test were used for data analysis.

Results

Our findings revealed that perceived level of posttraumatic growth was associated with greater positive affect, more effective emotion regulation, and higher level of general self‐efficacy. No significant correlation could be found between negative affect and perceived posttraumatic growth. In addition, positive affect partially mediated the effects of expressive revealing and general self‐efficacy on perceived posttraumatic growth while totally mediating the relationship between expressive suppression and perceived posttraumatic growth.

Conclusions

Positive affect, expressive revealing, and general self‐efficacy are important predictors of perceived posttraumatic growth among cancer survivors. Our findings also suggested that the effects of emotion regulation and general self‐efficacy upon perceived posttraumatic growth may be closely related to the level of positive affect. Copyright © 2013 John Wiley & Sons, Ltd.
The concerted action of a positive charge and hydrogen bonds dynamically regulates the pKa of the nucleophilic cysteine in the NrdH‐redoxin family
Authors: Van Laer Koen , Oliveira Margarida , Wahni Khadija , Messens Joris
Published: November 2013

NrdH‐redoxins shuffle electrons from the NADPH pool in the cell to Class Ib ribonucleotide reductases, which in turn provide the precursors for DNA replication and repair. NrdH‐redoxins have a CVQC active site motif and belong to the thioredoxin‐fold protein family. As for other thioredoxin‐fold proteins, the pKa of the nucleophilic cysteine of NrdH‐redoxins is of particular interest since it affects the catalytic reaction rate of the enzymes. Recently, the pKa value of this cysteine in Corynebacterium glutamicum and Mycobacterium tuberculosis NrdH‐redoxins were determined, but structural insights explaining the relatively low pKa remained elusive. We subjected C. glutamicum NrdH‐redoxin to an extensive molecular dynamics simulation to expose the factors regulating the pKa of the nucleophilic cysteine. We found that the nucleophilic cysteine receives three hydrogen bonds from residues within the CVQC active site motif. Additionally, a fourth hydrogen bond with a lysine located N‐terminal of the active site further lowers the cysteine pKa. However, site‐directed mutagenesis data show that the major contribution to the lowering of the cysteine pKa comes from the positive charge of the lysine and not from the additional Lys‐Cys hydrogen bond. In 12% of the NrdH‐redoxin family, this lysine is replaced by an arginine that also lowers the cysteine pKa. All together, the four hydrogen bonds and the electrostatic effect of a lysine or an arginine located N‐terminally of the active site dynamically regulate the pKa of the nucleophilic cysteine in NrdH‐redoxins.
Self‐assembling organo‐peptide bolaphiles with KLK tripeptide head groups display selective antibacterial activity
Authors: Naidoo Venthan B. , Rautenbach Marina
Published: November 2013

In keeping with recent efforts to generate compounds for antibiotic and microbicide development, we focused on the creation of non‐natural organo‐peptide hybrids of antimicrobial peptide amides (KLK(L)nKLK‐NH2) derived from sapecin B and a self‐assembling oligoglycine organo‐peptide bolaphile containing an ω‐amino fatty acid residue. The hybrid organo‐peptide bolaphiles with two cationic KLK tripeptide motifs linked with an ω‐amino acid residue (penta‐, octa‐ or undecamethylene chain) maintained the self‐assembling properties of the root oligoglycine bolaphile. Electron microscopy clearly revealed complex supramolecular architectures for both sapecin B‐derived peptides and the hybrid analogues. FT‐IR spectroscopy indicated that the supramolecular structures were composed primarily of β‐sheets. CD revealed that the hybrid bolaphiles did not share the same secondary structures as the sapecin B peptides in solution. However, although secondary structures of antimicrobial peptides are central in the activity, the organo‐peptide bolaphiles also retained the potent antimicrobial activity of the leader sapecin B‐derived peptide against both Gram‐positive and Gram‐negative bacteria. In general, the hybrids were more selective than the sapecin B peptides, as they displayed little or no appreciable haemolytic activity. The results obtained herald a new approach for the design of purpose‐built hybrid organo‐peptide bolaphiles. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.
Solid oxide fuel cells for power generation
Authors: Singhal Subhash C.
Published: November 2013

Solid oxide fuel cells (SOFCs), based on an oxide ion conducting electrolyte, offer a clean, low‐pollution technology to electrochemically generate electricity at high efficiencies. These fuel cells provide many advantages over traditional energy conversion systems including high efficiency, reliability, modularity, fuel adaptability, and very low levels of SOx and NOx emissions. Quiet, vibration‐free operation of SOFCs also eliminates noise usually associated with conventional power generation systems. Furthermore, because of their high operation temperature (600–1000°C), some hydrocarbon fuels such as natural gas can be reformed within the cell stack eliminating the need for an expensive, external reformer. In spite of these advantages, the degree and extent of their market penetration really depends on the ability to reduce the cost of SOFC‐based power systems while ensuring their long‐term durability. This article reviews the cell and stack materials, cell designs, and present commercial status of power systems built using SOFCs.

This article is categorized under:

Fuel Cells and Hydrogen > Science and Materials

Fuel Cells and Hydrogen > Systems and Infrastructure
Purification and characterization of a prolyl endopeptidase isolated from Aspergillus oryzae
Authors: Kang Chao , Yu Xiao-Wei , Xu Yan
Published: November 2013

A new fungal strain that was isolated from our library was identified as an Aspergillus oryzae and noted to produce a novel proly endopeptidase. The enzyme was isolated, purified, and characterized. The molecular mass of the prolyl endopeptidase was estimated to be 60 kDa by using SDS-PAGE. Further biochemical characterization assays revealed that the enzyme attained optimal activity at pH 4.0 with acid pH stability from 3.0 to 5.0. Its optimum temperature was 30 °C and residual activity after 30 min incubation at 55 °C was higher than 80 %. The enzyme was activated and stabilized by Ca2+ but inhibited by EDTA (10 mM) and Cu2+. The K  m and k  cat values of the purified enzyme for different length substrates were also evaluated, and the results imply that the enzyme from A. oryzae possesses higher affinity for the larger substrates. Furthermore, this paper demonstrates for the first time that a prolyl endopeptidase purified from A. oryzae is able to hydrolyze intact casein.
Modified Triglyceride Oil Through Reactions with Phenyltriazolinedione
Authors: Biswas Atanu , Cheng H. N. , Kim Sanghoon , Liu Zengshe
Published: November 2013

Most of the current lubricants originate from petroleum stock, which may make them difficult to dispose of and be environmentally unfriendly. Triglyceride oils are good platforms for new products that can substitute for conventional mineral oil‐based lubricating oils and synthetic esters. As part of the effort to develop new uses of triglyceride oils, a modified triglyceride oil was synthesized through the reactions with 4‐phenyl‐1,2‐4‐triazoline‐3,5‐dione (PTAD). The process required no solvent or catalyst and entailed only the mixing of triglyceride and PTAD. 1H NMR was used for structure determination and to monitor the reactions. Several reaction products were produced, and their relative yields depended on the stoichiometry and temperature of the reaction. The reaction product mixture exhibited a self‐curing behavior as a function of time. Thus, the viscosity of a mixture containing PTAD and triglyceride in a 3:10 weight ratio increased 40‐fold in about 2 h at room temperature, suggesting its possible use as an additive in lubricants, caulking, cement and thickener applications.
Interracial Marriage, Migration and Loving
Authors: Gevrek Deniz
Published: November 2013

The United States Supreme Court decision in the case of Loving v. Virginia in 1967, which forced 16 Southern states to strike down their anti-miscegenation laws, creates a unique opportunity to explore the impact of an exogenous change in a state's laws regulating interracial marriages. This study investigates the relationship between anti-miscegenation laws, black/white interracial marriage and black Americans’ geographical distribution using three decades of the U.S. census data. The results suggest that the timing and voluntary/involuntary repeal of statutes banning black/white interracial marriages impacted the locational distribution of married black males. The relationship is less clear-cut for black females. However, length of exposure to anti-miscegenation laws is found to be related to the geographical sorting patterns of both black males and females. A few patterns in the data suggest that social norms and local culture may be influential in this relationship and the findings imply that unless a society is ready to change, the government cannot fully offset the negative impact of past bans and punishments.
Vegetation and fire history since the last glacial maximum in an inland area of the western Mediterranean Basin (Northern Iberian Plateau, NW Spain)
Authors: Morales-Molino César , García-Antón Mercedes
Published: November 2013

We reconstructed vegetation responses to climate oscillations, fire and human activities since the last glacial maximum in inland NW Iberia, where previous paleoecological research is scarce. Extremely sparse and open vegetation composed of steppic grasslands and heathlands with scattered pioneer trees suggests very cold and dry conditions during the Oldest Dryas, unsuitable for tree survival in the surroundings of the study site. Slight woodland expansion during the Bølling/Allerød was interrupted by the Younger Dryas cooling. Pinewoods dominated for most of the early Holocene, when a marked increase in fire activity occurred. Deciduous trees expanded later reaching their maximum representation during the mid-Holocene. Enhanced fire activity and the presence of coprophilous fungi around 6400–6000 cal yr BP suggest an early human occupation around the site. However, extensive deforestation only started at 4500 cal yr BP, when fire was used to clear the tree canopy. Final replacement of woodlands with heathlands, grasslands and cereal crops occurred from 2700 cal yr BP onwards due to land-use intensification. Our paleoecological record can help efforts aimed at restoring the natural vegetation by indicating which communities were dominant at the onset of heavy human impact, thus promoting the recovery of currently rare oak and alder stands.
The Political Economy of Land Privatization in Argentina and Australia, 1810–1850: A Puzzle
Authors: Dye Alan , La Croix Sumner
Published: November 2013

In early public land privatization, governments in New South Wales and Buenos Aires provided forde juretransfer of public lands. In New South Wales the government lost control; squatters rushed out unlawfully and seizedde factofrontier claims. But in Buenos Aires privatization was accomplished byde juretransfers. Why did British settlers rejectde juretransfers from a government, most able to secure property rights and rule of law, while settlers of thepampafrontier, where property-rights security was doubtful, complied withde juretransfers? We find that the revenue objective and violence on the frontier explain this puzzle.
The Formative Years of the Modern Corporation: The Dutch East India Company VOC, 1602–1623
Authors: Gelderblom Oscar , de Jong Abe , Jonker Joost
Published: November 2013

With their legal personhood, permanent capital, transferable shares, separation of ownership and management, and limited liability, the Dutch and English colonial trading companies VOC and EIC are considered institutional breakthroughs. We analyze the VOC's business operations and financial policy and show that its novel corporate form owed less to foresight than to piecemeal engineering to remedy design flaws. The crucial feature of managerial limited liability was not, as previously thought, integral to that design, but emerged only after protracted experiments with various solutions to the company's financial bottlenecks. Legal form followed economic function, not the other way around.
High-throughput genotyping assay for the large-scale genetic characterization ofCryptosporidiumparasites from human and bovine samples
Authors: ABAL-FABEIRO J. L. , MASIDE X. , LLOVO J. , BELLO X. , TORRES M. , TREVIÑO M. , MOLDES L. , MUÑOZ A. , CARRACEDO A. , BARTOLOMÉ C.
Published: November 2013

The epidemiological study of human cryptosporidiosis requires the characterization of species and subtypes involved in human disease in large sample collections. Molecular genotyping is costly and time-consuming, making the implementation of low-cost, highly efficient technologies increasingly necessary. Here, we designed a protocol based on MALDI-TOF mass spectrometry for the high-throughput genotyping of a panel of 55 single nucleotide variants (SNVs) selected as markers for the identification of commongp60subtypes of fourCryptosporidiumspecies that infect humans. The method was applied to a panel of 608 human and 63 bovine isolates and the results were compared with control samples typed by Sanger sequencing. The method allowed the identification of species in 610 specimens (90·9%) andgp60subtype in 605 (90·2%). It displayed excellent performance, with sensitivity and specificity values of 87·3 and 98·0%, respectively. Up to nine genotypes from four differentCryptosporidiumspecies (C. hominis, C. parvum, C. meleagridisandC. felis) were detected in humans; the most common ones wereC. hominissubtype Ib, andC. parvumIIa (61·3 and 28·3%, respectively). 96·5% of the bovine samples were typed as IIa. The method performs as well as the widely used Sanger sequencing and is more cost-effective and less time consuming.