bluuebunny/crossref_metadata_2025 huggingface dataset:
Levels of Neutrophil Gelatinase-Associated Lipocalin in 2 Patients With Crush Syndrome After a Mudslide
Authors: Donato Valentina , Noto Alberto , Lacquaniti Antonio , Bolignano Davide , Versaci Antonio , David Antonio , Spinelli Francesco , Buemi Michele
Published: September 2011

Neutrophil gelatinase-associated lipocalin is one of the most promising biomarkers for the diagnosis of acute kidney injury. An increase in the level of neutrophil gelatinase-associated lipocalin is a good predictor of acute kidney injury and is associated with an increase in the serum level of creatinine. Two victims of a mudslide in Messina, Italy, initially had crush syndrome followed by development of acute kidney injury. The development of acute kidney injury is the second most common cause of death after large earthquakes and other natural disasters, but at the same time, crush-related acute kidney injury is one of the few life-threatening complications of crush injuries that can be reversed if diagnosed early and treated. In this case, measuring the level of neutrophil gelatinase-associated lipocalin enabled early diagnosis of acute kidney injury and anticipation of the changes in levels of conventional markers such as creatinine.
Inverse Semigroups and Sheu's Groupoid for Odd Dimensional Quantum Spheres
Authors: Sundar S.
Published: September 2011

In this paper, we give a different proof of the fact that the odd dimensional quantum spheres are groupoid C*-algebras. We show that the C*-algebra is generated by an inverse semigroup T of partial isometries. We show that the groupoid 𝓖tight associated with the inverse semigroup T by Exel is exactly the same as the groupoid considered by Sheu.
The climate penalty for clean fossil fuel combustion
Authors: Junkermann W. , Vogel B. , Sutton M. A.
Published: September 2011

Abstract. To cope with the world's growing demand for energy, a large number of coal-fired power plants are currently in operation or under construction. To prevent environmental damage from acidic sulphur and particulate emissions, many such installations are equipped with flue gas cleaning technology that reduces the emitted amounts of sulphur dioxide (SO2) and nitrogen dioxide (NO2). However, the consequences of this technology for aerosol emissions, and in particular the regional scale impact on cloud microphysics, have not been studied until now. We performed airborne investigations to measure aerosol size distributions in the air masses downwind of coal-fired power installations. We show how the current generation of clean technology reduces the emission of sulphur and fine particulate matter, but leads to an unanticipated increase in the direct emission of ultrafine particles (1–10 nm median diameter) which are highly effective precursors of cloud condensation nuclei (CCN). Our analysis shows how these additional ultrafine particles modify cloud microphysics, as well as precipitation intensity and distribution on a regional scale downwind of emission sources. Effectively, the number of small water droplets is increased, thus reducing the water available for large droplets and rain formation. The corresponding changes in the precipitation budget with a shift from more frequent steady rain to occasionally more vigorous rain events, or even a significant regional reduction of annual precipitation, introduce an unanticipated risk for regional climate and agricultural production, especially in semi-arid climate zones.
An Immunohistochemical Panel to Differentiate Metastatic Breast Carcinoma to Skin From Primary Sweat Gland Carcinomas With a Review of the Literature
Authors: Rollins-Raval Marian , Chivukula Mamatha , Tseng George C , Jukic Drazen , Dabbs David J
Published: September 2011

Context.—Approximately 25% of patients with breast cancer develop cutaneous metastases. Sweat gland carcinomas (SGCs) account for about 0.05% of all cutaneous neoplasms. Cutaneous metastases of breast carcinoma (CMBCs) (especially the ductal type) can be difficult to distinguish from SGCs. Treatment and prognoses for these 2 types of tumors differ radically, making accurate histologic diagnosis crucial. Although a few studies attempt to differentiate these entities employing immunohistochemical (IHC) studies (some of which we review here), to date, no panel of IHC stains exists, to our knowledge, to distinguish these entities.

Objective.—To devise a panel of IHC stains to distinguish CMBC from SGC.

Design.—Twelve cases of ductal CMBCs (11 not otherwise specified type, and 1 basal phenotype), 11 cases of SGCs (5 eccrine carcinomas, 3 porocarcinomas, and 3 microcystic adnexal carcinomas), 2 benign sweat gland neoplasm cases, and 2 primary breast cancer cases were retrieved and analyzed with the following IHC panel: mammaglobin, gross cystic disease fluid protein (GCDFP) 15, p63, basal cytokeratins (CK5, CK14, and CK17), androgen receptor, and PAX5.

Results.—The p63 was only weakly expressed in 1 of 12 CMBC cases (8.3%), whereas it was strongly expressed in 10 of 11 SGC cases (90.9%) (P < .001). Basal cytokeratins demonstrated a similar immunoprofile in the SGC group, with 10 of 11 cases (90.9%) expressing all 3 markers, and a variable immunoprofile in the CMBC group with 0% (CK14) (P < .001) to 16.7% (2 of 12 cases; CK5 and CK17) (P < .001) expression. Mammaglobin was expressed in 8 of 12 cases (66.7%) of CMBC.

Conclusions.—Together, these 5 IHC stains were combined to make a panel that was 100% sensitive and 91% specific in distinguishing between CMBC and SGC.
A Study of Pathologic Risk Factors in Postchemoreduced, Enucleated Specimens of Advanced Retinoblastomas in a Developing Country
Authors: Suryawanshi Pallavi , Ramadwar Mukta , Dikshit Rajesh , Kane Shubhada V , Kurkure Purna , Banavali Shripad , Viswanathan Seethalakshmi
Published: September 2011

Context.—Advanced cases of retinoblastoma are treated with chemoreduction followed by enucleation. Further adjuvant therapy is recommended in patients with known pathologic risk factors (PRFs).

Objectives.—To determine the PRFs in enucleated specimens after chemoreduction and their association for adverse events of recurrence, metastasis, or death.

Design.—This was a retrospective study of 77 enucleation specimens from patients treated between January 2000 and September 2008 with prior chemoreduction that were accessioned in the pathology department of a tertiary referral cancer center with an average follow-up of 24 months. Various PRFs were noted and their association with the development of an adverse event was recorded.

Results.—Of 77 patients, (male to female ratio, 51∶26), the incidence of overall PRF was 51.9%, and retrolaminar optic nerve invasion (32.5%), optic nerve cut margin (12.9%), massive choroidal invasion (26%), scleral invasion (23.4%), vitreous seedings (44.2%), and anterior segment invasion (20.8%). Undifferentiated tumor (>60%) was seen in 60.3% of cases (41 of 68 patients with differentiation available). Adverse event occurred in 18 of 72 patients with available follow-up (25%). Retrolaminar optic nerve invasion, optic nerve cut margin involvement, and scleral invasion were independent prognostic factors predicting the occurrence of an adverse event. Undifferentiated tumor (>60%) was a significant risk factor in univariate analysis, which is the unique feature in this study.

Conclusions.—Classic PRF with the addition of a predominant presence from the undifferentiated component were associated with adverse outcomes in retinoblastoma treated with anterior chemotherapy. The latter may represent chemoresistant clones and more intensive adjuvant chemotherapy may be warranted in these patients.
Malalignment and subchondral bone turnover in contralateral knees of overweight/obese women with unilateral osteoarthritis: Implications for bilateral disease
Authors: Mazzuca Steven A. , Brandt Kenneth D. , Lane Kathleen A. , Chakr Rafael
Published: September 2011

Objective

To explore whether the risk of incident tibiofemoral (TF) osteoarthritis (OA) in the radiographically normal contralateral knee of overweight/obese women with unilateral knee OA is mediated by malalignment and/or preceded by increased turnover of subchondral bone.

Methods

We used data of post hoc analyses from a randomized controlled trial. Cross‐sectional analyses evaluated the baseline association between frontal plane alignment and bone turnover in the medial TF compartment in 78 radiographically normal contralateral knees. Longitudinal analyses ascertained whether incident radiographic OA (TF osteophyte formation within 30 months) was associated with malalignment and/or increased bone turnover at baseline. Alignment subcategories (varus/neutral/valgus) were based on the anatomic axis angle. 99mTc–methylene diphosphonate uptake in a late‐phase bone scan was quantified in regions of interest in the medial tibia (MT) and medial femur (MF) and adjusted for uptake in a reference segment of the ipsilateral tibial shaft (TS).

Results

MF and MT uptake in varus contralateral knees was 50–55% greater than in the TS. Adjusted MT uptake in varus contralateral knees was significantly greater than that in neutral and valgus contralateral knees (mean 1.55 versus 1.38 and 1.43, respectively; P < 0.05). Among 69 contralateral knees followed longitudinally, 22 (32%) developed TF OA. Varus angulation was associated with a marginally significant increase in the odds of incident OA (adjusted odds ratio 3.98, P = 0.067).

Conclusion

While the small sample size limited our ability to detect statistically significant risk factors, these data suggest that the risk of developing bilateral TF OA in overweight/obese women may be mediated by varus malalignment.
Effect of self‐efficacy and physical activity goal achievement on arthritis pain and quality of life in patients with rheumatoid arthritis
Authors: Knittle Keegan P. , De Gucht Véronique , Hurkmans Emalie J. , Vlieland Thea P. M. Vliet , Peeters André J. , Ronday H. Karel , Maes Stan
Published: September 2011

Objective

To examine physical activity and achievement of physical activity goals in relation to self‐reported pain and quality of life among patients with rheumatoid arthritis (RA).

Methods

At baseline, 271 patients with RA were asked to specify a physical activity goal, and filled in questionnaires assessing physical activity, motivation, and self‐efficacy for physical activity, arthritis pain, and quality of life. Six months later, patients indicated to what extent they had achieved their baseline physical activity goal and completed the same set of questionnaires. These data were used to construct multiple mediation models that placed physical activity and physical activity goal achievement as mediators between self‐efficacy and motivation on one hand, and arthritis pain and quality of life on the other.

Results

A total of 106 patients with RA completed both questionnaires. Self‐efficacy at baseline predicted subsequent level of physical activity and achievement of physical activity goals. Goal achievement had a direct effect upon quality of life outcomes. Bootstrapping confidence intervals revealed indirect effects of self‐efficacy upon arthritis pain and quality of life through goal achievement, but not through physical activity.

Conclusion

Higher levels of self‐efficacy for physical activity increase the likelihood that patients will achieve their physical activity goals. Achievement of physical activity goals seems to be related to lower self‐reported arthritis pain, and higher levels of quality of life. In practice, clinicians can foster self‐efficacy and goal achievement by assisting patients in setting realistic and attainable exercise goals, developing action plans, and by providing feedback on goal progress.
Muscle strength, mass, and quality in older men and women with knee osteoarthritis
Authors: Conroy Molly B. , Kwoh C. Kent , Krishnan Eswar , Nevitt Michael C. , Boudreau Robert , Carbone Laura D. , Chen Hepei , Harris Tamara B. , Newman Anne B. , Goodpaster Bret H. ,   Health ABC Study
Published: September 2011

Objective

To examine the relationship between knee osteoarthritis (OA) and muscle parameters in a biracial cohort of older adults.

Methods

Participants in the Health, Aging and Body Composition Study (n = 858) were included in this cross‐sectional analysis. Computed tomography was used to measure muscle area, and quadriceps strength was measured isokinetically. Muscle quality (specific torque) was defined as strength per unit of muscle area for both the entire thigh and quadriceps. Knee OA was assessed based on radiographic features and knee pain. We compared muscle parameters between those with and without radiographic knee OA (+RKOA group and −RKOA group, respectively) and among 4 groups defined by +RKOA and −RKOA with and without pain.

Results

The mean ± SD age was 73.5 ± 2.9 years and the mean ± SD body mass index (BMI) was 27.9 ± 4.8 kg/m2. Fifty‐eight percent of participants were women and 44% were African American. Compared to the −RKOA participants, +RKOA participants had a higher BMI (30.2 versus 26.8 kg/m2), larger thigh muscles (117.9 versus 108.9 cm2), and a greater amount of intermuscular fat (12.5 versus 9.9 cm2; all P < 0.0001). In adjusted models, the +RKOA participants had significantly lower specific torque (P < 0.001), indicating poorer muscle quality, than −RKOA participants, but there was no difference between groups in quadriceps specific torque. The +RKOA without pain (P < 0.05) and the +RKOA with pain (P < 0.001) participants had lower specific torque compared to the −RKOA without pain group. There were no significant differences in quadriceps specific torque among groups.

Conclusion

Muscle quality was significantly poorer in participants with RKOA regardless of pain status. Future studies should address how lifestyle interventions might affect muscle quality and progression of knee OA.
Combined impact of concomitant arthritis and back problems on health status: Results from a nationally representative health survey
Authors: Bollegala Dimitri , Perruccio Anthony V. , Badley Elizabeth M.
Published: September 2011

Objective

To investigate whether people who report both arthritis and back problems report poorer health outcomes than those who have either condition alone.

Methods

We performed an analysis of the 2005 Canadian Community Health Survey (n = 126,049, age ≥15 years). Respondents were asked about long‐term chronic health conditions diagnosed by a health professional and lasting 6 months or more. The risks of reporting 4 health outcomes (activity limitation, fair/poor self‐rated overall health, fair/poor self‐rated mental health, and ≥4 doctor consultations in the previous 12 months) were estimated using log Poisson regression analysis adjusting for sociodemographic and lifestyle factors for 5 analytic groups (arthritis and back problems, arthritis only, back problems only, any other chronic condition, and no chronic condition).

Results

Arthritis and back problems were reported by 6% of the population (10.5% arthritis only and 13% back problems only). The arthritis and back problems and arthritis only groups had a higher prevalence in women, those of older age, and those who were overweight or obese. For all health outcomes, prevalence ratios showed higher risks of poor outcome for the arthritis and back problem group than for arthritis only or back problems only groups, which had similar risk. Risks were lowest for the any other chronic conditions group and the no chronic conditions group.

Conclusion

Chronic back problems were reported by one‐third of people with arthritis, who had increased risks of activity limitation, poorer self‐rated overall and mental health, and higher health care use. The findings suggest that concomitant back problems are a major contributor to a range of health outcomes in arthritis.
Autoantibody response to adjuvant and nonadjuvant H1N1 vaccination in systemic lupus erythematosus
Authors: Urowitz Murray B. , Anton Anoja , Ibanez Dominique , Gladman Dafna D.
Published: September 2011

Objective

It has been reported that influenza vaccination increases autoantibody production and/or disease activity in a significant proportion of patients with systemic lupus erythematosus (SLE). During the recent H1N1 epidemic, we investigated whether the use of adjuvant‐ and nonadjuvant‐containing H1N1 vaccine induced increased autoantibody production in patients with SLE.

Methods

Patients with SLE who received H1N1 vaccination and had a battery of 9 autoantibodies tested before and 1 and 3 months after vaccination were included. Antibodies tested included rheumatoid factor (nephelometry), antinuclear antibody (immunofluorescence), anti‐DNA (Farr), anti‐RNP, anti‐Sm, anti‐Ro, anti‐La, anti–Scl‐70, and anti–Jo‐1 (enzyme‐linked immunosorbent assay). Patients were evaluated by standard protocol, including items necessary to calculate the Systemic Lupus Erythematosus Disease Activity Index 2000 and the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index. Descriptive statistics and McNemar's test were performed to evaluate change in antibody positivity. Multivariate logistic regression was performed to adjust for repeated measures in the comparisons of autoantibodies over visits and vaccine types.

Results

One hundred three patients (94 women, 9 men) with a mean ± SD age at vaccination of 43.9 ± 15.2 years and a mean ± SD disease duration of 14.2 ± 11.0 years were included. Fifty‐one patients received adjuvant and 52 received nonadjuvant vaccines. Antibody testing was performed a mean of 1.9 months prior to the vaccination. The first postvaccination sample was taken a mean of 1 month after vaccination and the second a mean of 3.5 months after vaccination. The percentage of patients with changes in antibodies following vaccination was not statistically significant for most antibodies. After adjusting for the number of tests performed, none of the associations was significant.

Conclusion

H1N1 vaccination (both adjuvant and nonadjuvant) did not increase the levels of autoantibodies in patients with SLE.
Decentralized adaptive robust stabilization of uncertain interconnected time‐delay systems
Authors: Ghosh Sandip , Das Sarit K. , Ray Goshaidas
Published: September 2011

This paper considers the problem of decentralized adaptive robust stabilization of a class of interconnected time‐delay systems with arbitrarily bounded matched but limitedly bounded unmatched uncertainties. A new class of decentralized adaptive controllers based on Lyapunov–Krasovskii functional is proposed that guarantees bounded stability of the system and ensures nonfragileness of the controller to perturbations in its nonadaptive gain factor. The existence of such controllers is formulated in the LMI framework besides being presented using the Algebraic Riccati Equations. A numerical example is considered to illustrate the applicability and effectiveness of the proposed controller. Copyright © 2011 John Wiley & Sons, Ltd.
Bioengineering of a Semiautologous Arterial Vessels with Reconstructed Media and Intima, Longtime Tested In Vivo
Authors: Sagban Tolga Atilla , Schiegel Eleonore , Grabitz Klaus , Sandmann Wilhelm , Balzer Kai Michael
Published: September 2011

Goal was to engineer biological, arterial grafts with antithrombotic, autologous endothelial luminal surface combined with extraluminal smooth vascular muscle layer (VSMC) and to test in vivo. (1) Different decellularisation methods described in literature were compared to identify the most suitable one with focus on the preservation of extracellular fibre matrix. (2) Endothelial precursor cells (EPC), isolated from bone marrow and VSMC from small venous segments of donor animals were cultivated. Cells were seeded sandwich‐like on homologous decellularized venous scaffolds and conditioned under pulsatile circulation in a bioreactor. (3) The semiautologous grafts were implanted in carotidal position on both sides in five Beagle dogs (n = 10; group 2) as interposition. A group of five animals, receiving only acellular grafts in both carotid positions (n = 10; group 1) served as controls. Comparison of four in literature described decellularisation methods showed different preservation of elastic and collagen fibres compared with native veins, whereas decellularity was similar in all methods. This forced us to choose a decellularization protocol with the best preservation of the extracellular matrix. The in vivo experiments showed in group 1 (control) already after one week a complete thrombotic occlusion of the decellularized implants, whereas in group 2 9/10 semiautologous grafts were patent after 98 ± 4 days in ultrasound, angiography and histology (p = 0.0001). A complete incorporation of semiautologous grafts in the surrounding tissue could be shown. The seeding with two different cell types preserved an aneurysmatic degeneration under arterial conditions with patency without anticoagulation.
Electrochemical Investigations of Polyethylene Glycol‐Based “Soggy Sand” Electrolytes – From the Local Mechanism to the Overall Conduction
Authors: Jarosik Anna , Pfaffenhuber Christian , Bunde Armin , Maier Joachim
Published: September 2011

Using the example of SiO2 dispersions in LiClO4/polyethylene glycol electrolytes, the conduction mechanism of “soggy sand” electrolytes is discussed. The study is essentially based on zeta potential, impedance and transference number measurements as well as on modeling. All the results can be explained by anion adsorption by the oxide particles and increased concentration of free Li+ in the double layer. The initially colloidal dispersion quickly forms fractal networks by cluster–cluster aggregation. Once they percolate, an interfacially dominated Li+ conductance is observed. The subsequent coarsening of the network is self‐decelerating leading to a steady state conductivity that is, for low volume fractions, enhanced compared to SiO2 free electrolytes. At higher values, blocking and inhomogeneity effects (e.g., salt trapping) lead to decreased values of the overall conductivity.
Modular Functionalization of Electrodes by Cross‐Coupling Reactions at Their Surfaces
Authors: Müri Marcel , Gotsmann Bernd , Leroux Yann , Trouwborst Marius , Lörtscher Emanuel , Riel Heike , Mayor Marcel
Published: September 2011

Due to the increasing importance of modified electrodes for many applications in nanotechnology, including molecular electronics, bioelectronics, and sensors, there is a need to find ways to chemically attach suitable molecular films onto the electrodes. Combining the electroreduction of aryl diazonium salts with the Sonogashira cross‐coupling reaction, a new modular technique to modify electrodes is presented. The new technique allows a wide range of functional groups to be introduced onto electrode surfaces with high surface coverage by the functional subunit. Various organic subunits, including redox chromophores, are successfully attached to platinum electrodes. The corresponding films are characterized using cyclic voltammetry, X‐ray photoelectron spectroscopy, atomic force microscopy, and contact‐angle measurements. The electroreduction of diazonium salts is successfully achieved on a broad variety of conducting and semiconducting surfaces, which shows that the technique is applicable to a broad variety of substrates.
Polytopic Oxazoline‐Based Chiral Ligands for Cyclopropanation Reactions: A New Strategy to Prepare Highly Recyclable Catalysts
Authors: García José I. , Herrerías Clara I. , López‐Sánchez Beatriz , Mayoral José A. , Reiser Oliver
Published: September 2011

New polytopic chiral copper complexes based on azabis(oxazoline) moieties have been synthesized and applied in cyclopropanation reactions of several alkenes. Excellent enantioselectivities have been obtained in all cases and additionally, the catalysts have been recovered in up to 14 cycles without noticeable loss of activity and selectivity. Analysis of the copper complexes by mass spectrometry suggests the formation of coordination polymers, representing the resting state of the catalysts.
Current Trends in Asymmetric Synthesis with Aldolases
Authors: Clapés Pere , Garrabou Xavier
Published: September 2011

Biocatalytic carbon‐carbon bond formation by means of aldolases offers an exceptionally stereoselective and green tool for this strategic reaction in synthetic organic chemistry. Recent developments have shown that aldolases are particularly suitable catalysts for asymmetric framework construction and preparation of innovative molecules, which are valuable for investigations in drug discovery. Finding novel carboligases with unprecedented activities and engineering those available for improved substrate tolerance and stereoselectivity towards new synthetic challenges are fostering the advances in this field. Extensive knowledge of the precise reaction mechanism and the enzyme‐substrate interactions arising from biochemical and structural studies are leading to the development of novel catalysts by rational strategies, as well as to de novo computational design of enzymes. Besides, a number of industrially‐oriented processes with aldolases have been developed towards the production of drug precursors and dietary commodities.
Homoallylic Alcohols via a Chemo‐Enzymatic One‐Pot Oxidation–Allylation Cascade
Authors: Fuchs Michael , Schober Markus , Pfeffer Jan , Kroutil Wolfgang , Birner‐Gruenberger Ruth , Faber Kurt
Published: September 2011

A chemo‐enzymatic one‐pot, two‐step transformation of (hetero)‐benzylic and cinnamic alcohols to yield the elongated homoallylic sec‐alcohols in water in up to 96% isolated yield has been developed. The sequence comprised an enzymatic alcohol oxidation using galactose oxidase from Fusarium sp. NRRL 2903 to furnish the corresponding aldehydes, which were subjected directly to allylation via indium(0)‐mediated Barbier‐type coupling with allyl bromide or by addition of allylboronic acid pinacol ester.
Catalytic and Structural Features of Flavoprotein Hydroxylases and Epoxidases
Authors: Montersino Stefania , Tischler Dirk , Gassner George T. , van Berkel Willem J. H.
Published: September 2011

Monooxygenases perform chemo‐, regio‐ and/or enantioselective oxygenations of organic substrates under mild reaction conditions. These properties and the increasing number of representatives along with effective preparation methods place monooxygenases in the focus of industrial biocatalysis. Mechanistic and structural insights reveal reaction sequences and allow turning them into efficient tools for the production of valuable products. Herein we describe two biocatalytically relevant subclasses of flavoprotein monooxygenases with a close evolutionary relation: subclass A represented by p‐hydroxybenzoate hydroxylase (PHBH) and subclass E formed by styrene monooxygenases (SMOs). PHBH family members perform highly regioselective hydroxylations on a wide variety of aromatic compounds. The more recently discovered SMOs catalyze a number of stereoselective epoxidation and sulfoxidation reactions. Mechanistic and structural studies expose distinct characteristics, which provide a promising source for future biocatalyst development.
Flexibility of Substrate Binding of Cytosine‐5′‐Monophosphate‐N‐Acetylneuraminate Synthetase (CMP‐Sialate Synthetase) from Neisseria meningitidis: An Enabling Catalyst for the Synthesis of Neo‐sialoconjugates
Authors: He Ning , Yi Dong , Fessner Wolf‐Dieter
Published: September 2011

We have successfully established a simple continuous colorimetric assay for the sensitive and reliable quantification of cytosine‐5′‐monophosphate‐acetylneuraminate synthetase (CMP‐sialate synthetase, CSS) activity based on the pH change of a released proton equivalent upon nucleotide activation of Neu5Ac or related analogues. Using this method, steady‐state kinetic data of Neisseria meningitidis CSS were determined for cytosine‐5′‐triphosphate (CTP), N‐acetylneuraminic acid (Neu5Ac) and eleven structural variations of the sialic acid, including backbone truncation, deamination, epimerization, and several N‐acyl modifications. These data further demonstrate the unusual versatility of the N. meningitidis CSS for a general access to sialoconjugates containing non‐natural sialic acid analogues. Remarkably, the assay allows covering a broad range of substrate parameters that span over more than three orders of magnitude for KM and kcat measurements. With the aid of a structural model built from X‐ray crystal structure data, the kinetic data could be used to interpret potential protein contributions in substrate binding of Neu5Ac and its analogues. The Neu5Ac analogues were used for the preparation of neo‐sialoconjugate analogues of 2,6‐sialyllactose in a one‐pot two‐enzyme cascade, using N. meningitidis CSS together with the novel α2,6‐sialyltransferase (α2,6SiaT) from Photobacterium leiognathi, which proved to be highly effective because of its optimum activity at alkaline pH, appropriately matching the requirements from the overall reaction system.
Photo‐Carrier Recombination in Polymer Solar Cells Based on P3HT and Silole‐Based Copolymer
Authors: Chen Song , Choudhury Kaushik Roy , Subbiah Jegadesan , Amb Chad M. , Reynolds John R. , So Franky
Published: September 2011

Photo‐current loss in donor‐acceptor (DA) polymer‐fullerene bulk heterojunction solar cells was studied via carrier transport and recombination measurements. Focusing on the DA polymer poly((4,4‐dioctyldithieno (3,2‐b:2',3'‐d) silole)‐2,6‐diyl‐alt‐(2,1,3‐benzothiadiazole)‐4,7‐diyl) (DTS‐BTD) we found that the carrier transport is well‐balanced and attribute the loss mechanism in DTS‐BTD solar cells to carrier recombination. Using carrier extraction with linear increasing voltage (photo‐CELIV) and transient photo‐voltage (TPV), we show that carrier recombination plays an important role in photo‐current extraction at open circuit conditions due to increase in photo‐excited carrier concentration. Delay time dependent photo‐CELIV and temperature dependent transport studies suggest that the recombination rate is related to the degree of energetic disorder in the polymer: fullerene blends.
Feasibility analysis, synthesis, and design of reactive distillation processes: A focus on double‐feed processes
Authors: Théry‐Hétreux Raphaële , Meyer Xuan Mi. , Meyer Michel , Joulia Xavier , Brehelin Mathias , Amoros Daniel
Published: September 2011

A new approach for the feasibility analysis of reactive distillation processes based on the reactive extractive curve maps (rExCM) concept is introduced. A method dedicated to reactive distillation feasibility analysis, and design has been developed in our team since 1999. From minimal information concerning the physicochemical properties of the system, three steps lead to the design of the unit and the specification of its operating conditions. Currently, the procedure permits the conceptual design of hybrid reactive column configuration with one or two feed plates, for any number of equilibrium reactions (provided that the degree of freedom of the system is equal to 2) occurring in liquid or vapor phase. This contribution focuses on the most recent developments: the generalization of the feasibility analysis step to double‐feed processes thanks to the introduction of the rExCM concept. This methodology is illustrated through two examples: the emblematic methyl acetate example and the production of dimethyl methyl glutarate. © 2011 American Institute of Chemical Engineers AIChE J, 58: 2346–2356, 2012
Agricultural injury among rural California public high school students
Authors: McCurdy Stephen A. , Xiao Hong , Kwan Jonathan A.
Published: September 2011

Objectives

The University of California, Davis Youth Agricultural Injury Study characterized the farm work and agricultural injury experience among rural California Central Valley public high school students enrolled in an agricultural sciences curriculum.

Methods

We conducted a cross‐sectional survey of agricultural injury among students from 10 California Central Valley high schools during the 2001–2005 school years.

Results

Of 1,783 subjects, 946 (53.1%) reported farm work in the previous year, including 97 (10.3%) reporting at least one farm work‐related injury in the preceding year. After adjustment for sex, ethnicity, and hours spent in farm work, injury risk was associated with large‐animal operations (OR 4.15; 95%CI: 1.18, 14.65), feeding large animals (OR 2.38; 95%CI: 1.15, 4.96), mixing chemicals (OR 1.86; 95%CI: 1.15, 3.03), welding (OR 2.09; 95%CI: 1.17, 3.72), non‐use of seatbelts, and frequent riding in the back of an uncovered pick‐up truck. Risky attitudes toward farm safety were significantly associated with injury. Girls were more likely to suffer an animal‐related injury and boys to suffer injury related to motor vehicles, machinery, or tool use.

Conclusions

Adolescents are at similar risk to adults for agricultural injury. Although limitations on hazardous tasks and time spent on farm work are likely to be the most efficacious means for reducing injury, education will play an important role. Educational measures should include inculcating healthy safety‐related attitudes and focus on hazardous tasks, such as those involving animals (for girls) and motor vehicles and machinery (for boys). Am. J. Ind. Med. 55:63–75, 2012. © 2011 Wiley Periodicals, Inc.
A molecular phylogeny of the tamarins (genusSaguinus) based on five nuclear sequence data from regions containingAluinsertions
Authors: da Cunha Divino Bruno , Monteiro Eliene , Vallinoto Marcelo , Sampaio Iracilda , Ferrari Stephen F. , Schneider Horacio
Published: September 2011

This study presents a molecular phylogeny of theSaguinusgenus, based on the analysis of the DNA sequences of five nuclear loci withAluinsertions in 10 species. The concatenated alignment produced a polytomic arrangement with four main groups, although only two clades—the Amazonian (S. midas,S. niger, andS. bicolor) and the Colombian (S. leucopusandS. oedipus) tamarins—were statistically significant. The emergence of themidas‐bicolorclade was estimated at about 5 million years ago (mya), and that of the Colombian clade, at 4.6 mya. The phylogenetic relationships among the mustached tamarins (S. mystax,S. imperator, andS. labiatus) remained unresolved, as did the internal arrangement of themidasgroup. The lack of a clear consensus on the phylogeny of this group may be related to rapid bursts of evolutionary change within the context of a highly dynamic environment, which may be difficult to resolve using the available quantitative approaches. On the other hand, the discrepancies between mtDNA and nDNA in resolving phylogenies strongly indicate the role of reticulated evolution in the evolutionary history of this group. We hope that the advance of whole genome sequencing technology and increasing information on nuclear markers and SNPs, coupled with a better understanding of the geological phenomena that took place in western Amazonia over the past 20 million years, will shed further light on the phylogenetic history of these New World primates. Am J Phys Anthropol, 2011. © 2011 Wiley‐Liss, Inc.
Pathogenic protein seeding in alzheimer disease and other neurodegenerative disorders
Authors: Jucker Mathias , Walker Lary C.
Published: September 2011

The misfolding and aggregation of specific proteins is a seminal occurrence in a remarkable variety of neurodegenerative disorders. In Alzheimer disease (the most prevalent cerebral proteopathy), the two principal aggregating proteins are β‐amyloid (Aβ) and tau. The abnormal assemblies formed by conformational variants of these proteins range in size from small oligomers to the characteristic lesions that are visible by optical microscopy, such as senile plaques and neurofibrillary tangles. Pathologic similarities with prion disease suggest that the formation and spread of these proteinaceous lesions might involve a common molecular mechanism—corruptive protein templating. Experimentally, cerebral β‐amyloidosis can be exogenously induced by exposure to dilute brain extracts containing aggregated Aβ seeds. The amyloid‐inducing agent probably is Aβ itself, in a conformation generated most effectively in the living brain. Once initiated, Aβ lesions proliferate within and among brain regions. The induction process is governed by the structural and biochemical nature of the Aβ seed, as well as the attributes of the host, reminiscent of pathogenically variant prion strains. The concept of prionlike induction and spreading of pathogenic proteins recently has been expanded to include aggregates of tau, α‐synuclein, huntingtin, superoxide dismutase‐1, and TDP‐43, which characterize such human neurodegenerative disorders as frontotemporal lobar degeneration, Parkinson/Lewy body disease, Huntington disease, and amyotrophic lateral sclerosis. Our recent finding that the most effective Aβ seeds are small and soluble intensifies the search in bodily fluids for misfolded protein seeds that are upstream in the proteopathic cascade, and thus could serve as predictive diagnostics and the targets of early, mechanism‐based interventions. Establishing the clinical implications of corruptive protein templating will require further mechanistic and epidemiologic investigations. However, the theory that many chronic neurodegenerative diseases can originate and progress via the seeded corruption of misfolded proteins has the potential to unify experimental and translational approaches to these increasingly prevalent disorders. Ann Neurol 2011;70:532–540
Transformation of Carbon Dioxide with Homogeneous Transition‐Metal Catalysts: A Molecular Solution to a Global Challenge?
Authors: Cokoja Mirza , Bruckmeier Christian , Rieger Bernhard , Herrmann Wolfgang A. , Kühn Fritz E.
Published: September 2011

A plethora of methods have been developed over the years so that carbon dioxide can be used as a reactant in organic synthesis. Given the abundance of this compound, its utilization in synthetic chemistry, particularly on an industrial scale, is still at a rather low level. In the last 35 years, considerable research has been performed to find catalytic routes to transform CO2 into carboxylic acids, esters, lactones, and polymers in an economic way. This Review presents an overview of the available homogeneous catalytic routes that use carbon dioxide as a C1 carbon source for the synthesis of industrial products as well as fine chemicals.
Silver nanoparticle deposition on hydrophilic multilayer film surface and its effect on antimicrobial activity
Authors: Sánchez‐Valdes S. , Ramírez‐Vargas E. , Ortega‐Ortiz H. , Ramos‐deValle L. F. , Méndez‐Nonell J. , Mondragón‐Chaparro M. , Neira‐Velázquez G. , Yañez‐Flores I. , Meza‐Rojas D. E. , Lozuno‐Ramirez T.
Published: September 2011

Silver nanoparticles were deposited on the surface of the external polyamide 6 (PA6) layer of a multilayer film, by spraying and ultrasound‐assisted methods. The effect of silver nanoparticles content and deposition method on the mechanical and optical properties of the multilayered films as well as the efficiency of silver ion release and their fungicidal characteristics were evaluated. Itaconic (IA) and Maleic anhydride (MA) were used as adhesion promoter agents for preventing the agglomeration of the silver nanoparticles and for improving the adhesion to the PA6 polymer surface. With IA, a homogeneous distribution of silver nanoparticles on the PA6 surface was achieved. The silver ion release and biocide effect of the multilayered films was found to be dependent on the anhydride type and on the deposition method used. The multilayer films with a layer of PA6‐silver nanocomposite demonstrated good fungicidal activity, specifically against fungus Aspergillius niger. The observed results could be applied in the design of industrial films for packaging. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis of epoxy‐functionalized hyperbranched poly(phenylene oxide) and its modification of cyanate ester resin
Authors: Huang Pingzhen , Gu Aijuan , Liang Guozheng , Yuan Li
Published: September 2011

High curing temperature is the key drawback of present heat resistant thermosetting resins. A novel epoxy‐functionalized hyperbranched poly(phenylene oxide), coded as eHBPPO, was synthesized, and used to modify 2,2′‐bis (4‐cyanatophenyl) isopropylidene (CE). Compared with CE, CE/eHBPPO system has significantly decreased curing temperature owing to the different curing mechanism. Based on this results, cured CE/eHBPPO resins without postcuring process, and cured CE resin postcured at 230°C were prepared, their dynamic mechanical and dielectric properties were systematically investigated. Results show that cured CE/eHBPPO resins not only have excellent stability in dielectric properties over a wide frequency range (1–109Hz), but also show attractively lower dielectric constant and loss than CE resin. In addition, cured CE/eHBPPO resins also have high glass transition temperature and storage moduli in glassy state. These attractive integrated performance of CE/eHBPPO suggest a new method to develop high performance resins. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Atom transfer radical polymerization of styrene and methyl (meth)acrylates initiated with poly(dimethylsiloxane) macroinitiator: Synthesis and characterization of triblock copolymers
Authors: Semsarzadeh Mohammad Ali , Abdollahi Mahdi
Published: September 2011

Poly(dimethylsiloxane)(PDMS)‐based triblock copolymers were successfully synthesized via atom transfer radical polymerization (ATRP) initiated with bis(bromoalkyl)‐terminated PDMS macroinitiator (Br‐PDMS‐Br). First, Br‐PDMS‐Br was prepared by reaction between the bis(hydroxyalkyl)‐terminated PDMS and 2‐bromo‐2‐methylpropionyl bromide. PSt‐b‐PDMS‐b‐PSt, PMMA‐b‐PDMS‐b‐PMMA and PMA‐b‐PDMS‐b‐PMA triblock copolymers were then synthesized via ATRP of styrene (St), methyl methacrylate (MMA) and methyl acrylate (MA), respectively, in the presence of Br‐PDMS‐Br as a macroinitiator and CuCl/PMDETA as a catalyst system at 80 oC. Triblock copolymers were characterized by FTIR, 1H‐NMR and GPC techniques. GPC results showed linear dependence of the number‐average molecular weight on the conversion as well as the narrow polydispersity indicies (PDI < 1.57) for the synthesized triblock copolymers which was lower than that of Br‐PDMS‐Br macroinitiator (PDI = 1.90), indicating the living/controlled characteristic of the reaction. Also, there was a very good agreement between the number‐average molecular weight calculated from 1HNMR spectra and that calculated theoretically. Results showed that resulting copolymers have two glass transition temperatures, indicating that triblock copolymers have microphase separated morphology. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Influence of heat treatment on the heat distortion temperature of poly(lactic acid)/bamboo fiber/talc hybrid biocomposites
Authors: Shi Q. F. , Mou H. Y. , Li Q. Y. , Wang J. K. , Guo W.H.
Published: September 2011

Influence of heat treatment and fillers on the heat distortion temperature (HDT) of poly(lactic acid) hybrid biocomposites was intensively studied through HDT testing, polarizing microscope (POM), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). With loading 20 wt % BF or 20 wt % talc, improvement of HDT in PLA composite was about 10°C comparing with neat PLA after heat treatment. Moreover, there was a great improvement (above 45°C) of HDT in PLA composites with loading 20 wt % BF and 20 wt % talc simultaneously after heat treatment. Transcrystallization was observed during heat treatment and isothermal crystallization of PLA composites with loading BF and talc simultaneously. There was no similar phenomenon in other PLA composite with loading only one filler. The possible mechanism of forming transcrystallization was proposed. DSC and DMA were also used to clarify the variation in HDT before and after heat treatment, and the results suggest that the crystallinity, modulus and glass transition changed, especially formation of transcrystallization played a key role in improvement of HDT in PLA composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Poly(N‐isopropylacrylamide‐co‐hydroxyethyl methacrylate) graft copolymers and their application as carriers for drug delivery system
Authors: Quynh Tran Minh , Yoneyamab Masaru , Maki Yasuyuki , Dobashi Toshiaki
Published: September 2011

Poly(N‐isopropylacrylamide‐co‐hydroxyethyl methacrylate) [P(NIPAM‐co‐HEMA)] copolymer was synthesized by controlled radical polymerization from respective N‐isopropylacrylamide (NIPAM) and hydroxyethyl methacrylate (HEMA) monomers with a predetermined ratio. To prepare the thermosensitive and biodegradable nanoparticles, new thermosensitive graft copolymer, poly(L‐lactide)‐graft‐poly(N‐isoporylacrylamide‐co‐hydroxyethyl methacrylate) [PLLA‐g‐P(NIPAM‐co‐HEMA)], with the lower critical solution temperature (LCST) near the normal body temperature, was synthesized by ring opening polymerization of L‐lactide in the presence of P(NIPAM‐co‐HEMA). The amphiphilic property of the graft copolymers was formed by the grafting of the PLLA hydrophobic chains onto the PNIPAM based hydrophilic backbone. Therefore, the graft copolymers can self‐assemble into uniformly spherical micelles ò about 150–240 nm in diameter as observed by the field emission scanning electron microscope and dynamic light scattering. Dexamethasone can be loaded into these nanostructures during dialysis with a relative high loading capacity and its in vitro release depends on temperature. Above the LCST, most of the drugs were released from the drug‐loaded micelles, whereas a large amount of drugs still remains in the micelles after 48 h below the LCST. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Thermal, mechanical, and morphological properties of polylactic acid toughened with an impact modifier
Authors: Taib R. Mat , Ghaleb Z. A. , Mohd Ishak Z. A.
Published: September 2011

Polylactic acid (PLA) was melt‐blended with different amount (0 to 50 wt %) of a commercially available ethylene acrylate copolymer impact modifier. PLA/impact modifier blends were prepared via an internal mixer and compression molded into test specimens. The thermal, mechanical, and morphological properties of the blends were investigated. The addition of impact modifier decreased the ability of PLA to crystallize and/or recrystallize. The degree of crystallinity of PLA decreased while the cold crystallization temperature shifted to higher temperatures with increasing the impact modifier content. PLA/impact modifier blends were partially miscible. This was confirmed by the dynamic mechanical analysis (DMA) tests. With increasing the impact modifier content, the blends showed some improvement in the elongation at break and notched impact strength indicating the toughening effects of the impact modifier. In contrast, the yield stress and tensile modulus decreased with the increase in the impact modifier content. Scanning electron microscopy (SEM) micrographs revealed that the toughening mechanisms among others involved shear yielding or plastic deformation of the PLA matrix induced by interfacial debonding between the PLA and the impact modifier domains. PLA with 30 wt % impact modifier showed comparable yield stress and tensile modulus and better elongation at break and impact strength (+90%) than those of polypropylene (PP). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123:2715–2725, 2012