bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Unique Synthetic Method to Convert a D‐Sugar into 2‐Deoxy‐L‐ribitol Through Carbonyl Translocation
Authors: Hsu Nai‐Yun , Chang Che‐Chien 
Published: December 2012

AbstractA unique and highly efficient radical process was developed to prepare 2‐deoxy‐L‐ribitol. The radical cyclization precursor was prepared over several steps from D‐sugars. Radical cyclization followed by fragmentation gave exclusively the desired product, with carbonyl translocation in an acyclic carbohydrate system. The radical process was optimized to avoid the formation of byproducts. The reaction mechanism was studied by the concentration effect, which indicated that both the radical cyclization and the fragmentation steps are relatively rapid. The stereochemistry of the 2‐deoxy‐L‐ribitol was confirmed by X‐ray crystal structure. By using this synthetic approach, a D‐sugar derivative could be transformed into 2‐deoxy‐L‐ribose in a single radical reaction.
High‐reliable multi‐wavelength optical access network expanding by a single‐fiber tangent ring
Authors: Shao Qi , Gan Chaoqin 
Published: December 2012

ABSTRACTA highly reliable multi‐wavelength optical access network architecture based on single‐fiber and tangent rings is proposed. With the proposed architecture, both data convergence and protection can be realized. The primary ring can provide protection for the remote nodes (RNs) connected with its feeder fibers. The design of the RN used as the tangent point can realize the wavelength adding and dropping between the two tangent rings and it also realizes the network expansion of the optical access network. The protection of the RNs in sub‐ring can be realized by controlling the corresponding switches. Copyright © 2012 John Wiley & Sons, Ltd.
A correlation for predicting smoke layer temperature in a room adjacent to a room involved in a pre‐flashover fire
Authors: Johansson Nils , van Hees Patrick 
Published: December 2012

SUMMARYAdvanced fire modelling software have been developed and improved during the last couple of decays and these kinds of software have been shown to be valuable tools for fire safety engineers. However, the advances made have not replaced the need for simple hand‐calculation methods. Simple hand‐calculations methods can be used to obtain a first estimate of, for example, smoke layer temperatures in a performance‐based design or to help an engineer determine if it is necessary to perform a detailed computational fluid dynamics calculation, but the current hand‐calculations methods are limited. The current methods can for example only predict smoke gas temperatures in the fire room. A correlation that could predict temperatures in an adjacent space would be useful in performance‐based design when, for example, evaluating the conditions for evacuees or sensitive equipment in an adjacent space to the room of fire origin. In this paper, a correlation for predicting gas temperatures in a room adjacent to a room involved in a pre‐flashover fire is developed. The correlation is derived from results from computer simulations and the external validity is studied by comparing results from the correlation with full‐scale test data. Copyright © 2012 John Wiley & Sons, Ltd.
Microbiological and biochemical origins of human foot malodour
Authors: James A. Gordon , Cox Diana , Worrall Kathryn 
Published: December 2012

ABSTRACTAlthough foot malodour is a common consumer problem, the range of products available to combat the condition is fairly limited. In part, this is due to an incomplete understanding of how the key odorants are generated by microorganisms resident on the skin. The aim of these studies was to identify the key chemical components of foot malodour, the organisms and metabolic pathways responsible for their production, and to develop model systems to study these processes in vitro. Using gas chromatography with simultaneous mass spectrometry and sniff port detection, volatile fatty acids were implicated as foot malodorants, with isovaleric acid particularly prominent. l‐Leucine was identified as the likely substrate, and the source of this branched amino acid postulated to be the degradation of foot callus. An in vitro assay was employed to screen a library of isolated foot bacteria for their ability to generate isovaleric acid from l‐leucine. Staphylococcus species were found to be the main producers, while some Brevibacterium, Micrococcus and Kytococcus isolates fully catabolized isovaleric acid and l‐leucine, indicating the dynamic nature of odour production. The degradation of foot callus by Kytococcus sedentarius was investigated, and an in vitro ‘foot malodour model’ developed, demonstrating the generation of isovaleric acid using a combination of partially purified K. sedentarius keratinases and a Staphylococcus species. The results of these studies provide new understanding on the microbiological and biochemical origins of foot malodour which, in turn, should lead to the development of novel deodorant systems for this part of the body. Copyright © 2012 John Wiley & Sons, Ltd.
Extracellular aggregated Cu/Zn superoxide dismutase activates microglia to give a cytotoxic phenotype
Authors: Roberts Kate , Zeineddine Rafaa , Corcoran Lisa , Li Wen , Campbell Iain L. , Yerbury Justin J. 
Published: December 2012

AbstractA large body of literature suggests that amyotrophic lateral sclerosis (ALS) pathology is intimately linked with neuroinflammation, specifically activation and recruitment of microglia and astrocytes. The actual cause of gliosis is unclear. Extracellular Cu/Zn superoxide dismutase (SOD1) has recently been shown to activate microglia in a CD14 dependant mechanism providing one potential pathway by which glial cells become activated. As protein inclusions are thought to be an important part of ALS pathology and are associated with all forms of ALS, we sought to determine if aggregated SOD1 would activate microglia. Recombinant SOD1 was aggregated and this, or monomeric forms of SOD1 were then added to EOC.13 microglial cells or primary microglial cells in culture. Although monomeric mutant SOD1 has been shown to promote microglial activation in the past, we found that aggregated SOD1 was able to much more efficiently activate microglia in culture when compared with the unaggregated form of mutant SOD1. In addition to CD14 dependant pathways, aggregated SOD1 also bound to the surface of glial cells and was internalized in a lipid raft and scavenger receptor dependent manner. We have for the first time shown that aggregated mutant SOD1 potently activates microglia. These results suggest that there may be a potential link between protein aggregation and microglial activation in ALS. © 2012 Wiley Periodicals, Inc.
Survival of people with dementia after unplanned acute hospital admission: a prospective cohort study
Authors: Sampson Elizabeth L. , Leurent Baptiste , Blanchard Martin R. , Jones Louise , King Michael 
Published: December 2012

ABSTRACTObjectiveTo examine the effect of dementia on longer term survival after hospital admission, and to assess whether dementia is an independent predictor of mortality. This information is vital for the provision of appropriate care.MethodsA prospective cohort study, in a large urban acute general hospital, of 616 people (70 years and older) with unplanned medical admission. The principal exposure was DSM‐IV dementia and main outcome mortality risk. Dementia severity was analysed by using the Functional Assessment Staging scale. We examined a range of modifying variables: acute physiological disturbance (Acute Physiology and Chronic Health Evaluation), chronic comorbidity (Charlson Comorbidity Index, CCI) and pressure sore risk (Waterlow score).ResultsA total 42.4% of the cohort had dementia. Nearly half (48.3%) had died 12 months after admission (median survival time 1.1 years compared with 2.7 years in people without dementia). Unadjusted hazard ratios for mortality in people with dementia was 1.66 (95% CI 1.35–2.04) and for people with moderately severe/severe dementia 2.01 (95% CI 1.57–2.57). After sequential adjustment (age, gender, Acute Physiology and Chronic Health Evaluation score, Charlson Comorbidity Index and Waterlow score), patients with dementia had a mortality risk of 1.24 (95% CI 0.95–1.60) and those with moderately severe/severe dementia 1.33 (0.97–1.84).ConclusionsPeople with dementia had half the survival time of those without dementia. The effect of dementia on mortality was reduced after adjustment, particularly by the Waterlow score, a marker of frailty. The median survival of 1 year suggests clinicians should consider adopting a supportive approach to the care of older people with moderate/severe dementia who have an emergency hospital admission. Copyright © 2012 John Wiley & Sons, Ltd.
Promoting corporate social responsibility and sustainable development through management development: What can be learned from international service learning programs?
Authors: Pless Nicola M. , Maak Thomas , Stahl Günter K. 
Published: December 2012

AbstractIn this article, we discuss how the human resource development (HRD) function can support corporate sustainability strategy by designing and implementing leadership development programs incorporating international service learning assignments. We describe “Project Ulysses,” an integrated service learning program that involves sending participants in teams to developing countries to work in cross‐sector partnerships with nongovernmental organizations (NGOs) and social entrepreneurs, supporting them in their fight against pressing global problems. We present the findings of a narrative analysis of learning stories produced by Ulysses participants. Understanding how participants make sense of, and learn from, their experiences abroad provides us with insights into how service learning programs can help managers to develop the knowledge, skills, and mind‐set that will enable them to successfully support a company's global sustainability and corporate social responsibility (CSR) efforts. We conclude by discussing the implications for leadership development, specifically how organizations can incorporate a responsibility and sustainability focus in their management development programs.
Comparing the effects of two neurotoxins in cortical astrocytes obtained from rats of different ages: involvement of oxidative damage
Authors: Alarcón‐Aguilar Adriana , González‐Puertos Viridiana Yazmín , Luna‐López Armando , López‐Macay Ambar , Morán Julio , Santamaría Abel , Königsberg Mina 
Published: December 2012

ABSTRACTOxidative stress has been recognized as a potential mediator of cell death. Astrocytes play an active role in brain physiology responding to harmful stimuli by activating astrogliosis, which in turn has been associated either with survival or degenerative events. The characterization of the mechanistic actions exerted by different toxins in astrocytes is essential to understand the brain function and pathology. As age plays a critical role in degenerative processes, the aim of this study was to determine whether the administration of equimolar concentrations of two neurotoxins evoking different toxic patterns can induce differential effects on primary astrocytes obtained either from newborn or adult rats, with particular emphasis on those events linked to oxidative stress as a potential source of damage. Primary cortical astrocyte cultures derived from rat brains were exposed to 1‐methyl‐4‐phenylpyridinium (MPP+) or beta‐amyloid peptide (β‐amyloid). Mitochondrial functionality and cell viability were determined as physiological parameters, whereas lipid and protein oxidation were used as markers of oxidative damage. The results of these experiments pointed towards a higher vulnerability to MPP + over β‐amyloid, on most of the tested markers. Hence, in order to allow a comprehensive evaluation of astrocytic responses against MPP + intoxication, a third astrocyte group was included for dose‐response experiments: astrocytes derived from aged rats. The present data indicate that the differences associated with age were mainly found in astrocytes exposed to MPP + (25 and 50 μM) at 1‐h treatment. Results are discussed in terms of the differential mechanisms involved in each model. Copyright © 2012 John Wiley & Sons, Ltd.
Metabonomics evaluation of urine from rats administered with phorate under long‐term and low‐level exposure by ultra‐performance liquid chromatography‐mass spectrometry
Authors: Sun Xiaowei , Xu Wei , Zeng Yan , Hou Yurong , Guo Lin , Zhao Xiujuan , Sun Changhao 
Published: December 2012

ABSTRACTThe purpose of this study was to investigate the toxic effect of long‐term and low‐level exposure to phorate using a metabonomics approach based on ultra‐performance liquid chromatography‐mass spectrometry (UPLC‐MS). Male Wistar rats were given phorate daily in drinking water at low doses of 0.05, 0.15 or 0.45 mg kg–1 body weight (BW) for 24 weeks consecutively. Rats in the control group were given an equivalent volume of drinking water. Compared with the control group, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (TBIL), urea nitrogen (BUN) and creatinine (CR) were increased in the middle‐ and high‐dose groups whereas albumin (ALB) and cholinesterase (CHE) were decreased. Urine metabonomics profiles were analyzed by UPLC‐MS. Compared with the control group, 12 metabolites were significantly changed in phorate‐treated groups. In the negative mode, metabolite intensities of uric acid, suberic acid and citric acid were significantly decreased in the middle‐ and high‐dose groups, whereas indoxyl sulfic acid (indican) and cholic acid were increased. In the positive mode, uric acid, creatinine, kynurenic acid and xanthurenic acid were significantly decreased in the middle‐ and high‐dose groups, but 7‐methylguanine (N7G) was increased. In both negative and positive modes, diethylthiophosphate (DETP) was significantly increased, which was considered as a biomarker of exposure to phorate. In conclusion, long‐term and low‐level exposure to phorate can cause disturbances in energy‐related metabolism, liver and kidney function, the antioxidant system, and DNA damage. Moreover, more information can be provided on the evaluation of toxicity of phorate using metabonomics combined with clinical chemistry. Copyright © 2012 John Wiley & Sons, Ltd.
Layer‐by‐layer supramolecular assemblies based on linear and star‐shaped poly(glycerol methacrylate)s for doxorubicin delivery
Authors: Sun Yanfang , Gao Hui , Yang Ying‐Wei , Wang Anning , Wu Guolin , Wang Yinong , Fan Yunge , Ma Jianbiao 
Published: December 2012

AbstractHollow microcapsules, composed of pH responsive polyelectrolytes via a layer‐by‐layer (LBL) adsorption technique, were prepared. Linear or star‐shaped poly(glycerol metha crylate)s (PGOHMAs) modified with 1,4‐butanediamine and 1,2‐ethanediamine (EDA) were synthesized and used as polycations. Poly(acrylic acid) was employed as polyanion and SiO2 (about 170 nm) as template. After LBL absorption, SiO2 cores were removed by HF treatment. The particle size and zeta potential were measured by dynamic light scattering, showing that the diameter of star‐shaped amino‐PGOHMA was larger than linear counterpart. The LBL assembly and core‐etching process were evidenced by scanning electron microscope, transmission electron microscope, and energy dispersive spectrometer. The cytotoxicity experiments on human umbilical vein endothelial cells were carried out to evaluate the toxicity of LBL assembly. The star‐shaped and EDA‐modified PGOHMA exhibited better cell viability. The microcapsules were then used to load an anticancer drug, doxorubicin hydrochloride. High loading capacity (about 42%) and entrapment efficiency (84%) were obtained for star‐shaped polymer‐based microcapsules. The cumulative release rate was evaluated in vitro, showing faster release at an acidic condition compared to neutral pH. Confocal laser scanning microscopy evidenced the successful cellular uptake of DOX‐loaded microparticles. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Temporal MRI characterization of gelatin/hyaluronic acid/chondroitin sulfate sponge for cartilage tissue engineering
Authors: Chou Cheng‐Hung , Lee Herng‐Sheng , Siow Tiing Yee , Lin Ming‐Huang , Kumar Amit , Chang Yue‐Cune , Chang Chen , Huang Guo‐Shu 
Published: December 2012

AbstractA tri‐copolymer sponge consisting of gelatin, hyaluronic acid, and chondroitin sulfate (GHC) was designed to mimic the cartilage environment in vivo for cartilage regeneration. The present study aimed to temporally characterize the magnetic resonance relaxation time of GHC constructs in vivo in a rodent heterotopic model. GHC sponges with cells (GHCc) or without cells (GHC) implanted in rat leg muscle were monitored using MRI (4.7 T MR scanner) on day 0, 7, 14, and 21 after implantation. The results revealed that the transverse relaxation time (T2) of GHC constructs decreased significantly over time when compared to the T2 of GHCc constructs. However, the longitudinal relaxation time (T1) of GHCc and GHC constructs remained stable. Moreover, hematoxylin and eosin and immunohistochemical staining with antibodies to S100 protein, and types I and II collagen showed that normal morphology, phenotype, and function of chondrocytes were preserved in the GHCc construct. Thus, we concluded that GHC constructs adequately support chondrocyte growth and function. On top of that, T2 may be a useful tool for monitoring cartilage regeneration in GHC constructs. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Biodegradable and bioactive porous scaffold structures prepared using fused deposition modeling
Authors: Korpela Jyrki , Kokkari Anne , Korhonen Harri , Malin Minna , Närhi Timo , Seppälä Jukka 
Published: December 2012

AbstractThree‐dimensional printing (3DP) refers to a group of additive manufacturing techniques that can be utilized in tissue engineering applications. Fused deposition modeling (FDM) is a 3DP method capable of using common thermoplastic polymers. However, the scope of materials applicable for FDM has not been fully recognized. The purpose of this study was to examine the creation of biodegradable porous scaffold structures using different materials in FDM and to determine the compressive properties and the fibroblast cell response of the structures. To the best of our knowledge, the printability of a poly(ε‐caprolactone)/bioactive glass (PCL/BAG) composite and L‐lactide/ε‐caprolactone 75/25 mol % copolymer (PLC) was demonstrated for the first time. Scanning electron microscope (SEM) images showed BAG particles at the surface of the printed PCL/BAG scaffolds. Compressive testing showed the possibility of altering the compressive stiffness of a scaffold without changing the compressive modulus. Compressive properties were significantly dependent on porosity level and structural geometry. Fibroblast proliferation was significantly higher in polylactide than in PCL or PCL/BAG composite. Optical microscope images and SEM images showed the viability of the cells, which demonstrated the biocompatibility of the structures. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013.
Use of DXA-based finite element analysis of the proximal femur in a longitudinal study of hip fracture
Authors: Naylor Kim E , McCloskey Eugene V , Eastell Richard , Yang Lang 
Published: December 2012

Abstract
Bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) is used for clinical assessment of fracture risk; however, measurements that incorporate bone strength could improve predictive ability. The aim of this study was to determine whether bone strength derived from finite element (FE) analysis was associated with hip fracture risk in a longitudinal study. We studied 728 women (mean age 82 years), 182 with subsequent hip fracture. FE models were generated from baseline DXA scans of the hip to determine femoral bone strength and load-to-strength ratio (LSR). The baseline LSR was significantly higher in fracture cases (median 1.1) compared with controls (0.7, p &lt; 0.0001). Femoral strength and BMD were also significantly lower in cases (median 1820 N, 0.557 g/cm2) compared with controls (2614 N, 0.618 g/cm2) both p &lt; 0.0001. Fracture risk increased per standard deviation decrease in femoral strength (odds ratio [OR] = 2.2, 95% confidence interval [CI] 1.8–2.8); femoral neck (FN) BMD (OR = 2.1, 95% CI 1.7–2.6); total hip BMD (OR = 1.8, 95% CI 1.5–2.1); and per SD increase in LSR (OR = 1.8, 95% CI 1.5–2.1). After adjusting for FN BMD, the odds ratio for femoral strength (OR = 1.7, 95% CI 1.2–2.4) and LSR (OR = 1.4, 95% CI 1.1–1.7) remained significantly greater than 1. The area under the curve (AUC) for LSR combined with FN BMD (AUC 0.69, 95% CI 0.64–0.73) was significantly greater than FN BMD alone (AUC 0.66, 95% CI 0.62–0.71, p = 0.004). Strength and LSR remained significant when adjusted for prevalent fragility fracture, VFA, and FRAX score. In conclusion, the DXA-based FE model was able to discriminate incident hip fracture cases from controls in this longitudinal study independently from FN BMD, prior fracture, VFA, and FRAX score. Such an approach may provide a useful tool for better assessment of bone strength to identify patients at high risk of hip fracture who may benefit from treatment to reduce fracture risk. © 2013 American Society for Bone and Mineral Research.
Melamine Trisulfunic Acid: An Efficient and Recyclable Solid Acid Catalyst for the Synthesis of 4,4′‐(Arylmethylene)‐bis‐(1H‐pyrazol‐5‐ols)
Authors: Iravani Nasir , Albadi Jalal , Momtazan Hamide , Baghernejad Mojtaba 
Published: December 2012

AbstractMelamine trisulfunic acid is employed as a recyclable catalyst for the condensation reaction of aromatic aldehydes with 3‐methyl‐l‐phenyl‐2‐pyrazolin‐5‐one. This condensation reaction was performed in ethanol under refluxing conditions giving 4,4′‐(arylmethylene)‐bis‐(3‐methyl‐1‐phenyl‐1H‐pyrazol‐5‐ols) in 80‐96% yields.
Fe(NO3)3·9H2O as Efficient Catalyst for One‐pot Synthesis of Highly Functionalized Piperidines
Authors: Hazeri Nourallah , Maghsoodlou Malek Taher , Habibi‐Khorassani Sayyed Mostafa , Aboonajmi Jasem , Sajadikhah Seyed Sajad 
Published: December 2012

AbstractFe(NO3)3·9H2O is used as an efficient and effective catalyst for the one‐pot three‐component synthesis of highly functionalized piperidines from aromatic aldehydes, anilines and b–ketoesters in ethanol at ambient temperature. This procedure includes some important aspects like the easy work‐up, no need to column chromatography, simple and readily available precursors, and good to high yields.
Catalysis Studies of Macroreticular Polystyrene Cation‐exchange Resin with Terminal Perfluoroalkanesulfonic Acids
Authors: Lin Zhenghuan , Guan Chuanjin , Huang Limei , Wang Wen , Ling Qidan , Zhao Chengxue 
Published: December 2012

AbstractMacroreticular p‐(ω‐sulfonic‐perfluoroalkylated) polystyrene (FPS) resin with the advantages of both sulfonic polystyrene (such as macroreticular Amberlyst‐15) and perfluoroalkanesulfonic resin (such as superacidic Nafion NR50) has exhibited excellent catalytic selectivity and activity in cyclization of pseudoionone and condensation of indole. In this paper, FPS was characterized by XPS, nitrogen sorption technique, FESEM and Hammett indicator method, and employed as the solid acid catalyst in the esterification, acylation and alkylation reactions. The FPS resin showed better activity than commercial solid acid catalysts (Amberlyst‐15 and Nafion NR50) owing to its high surface area and strong acidity close to superacidity.