bluuebunny/crossref_metadata_2025 huggingface dataset:
Hand grab or noose pole? Evaluating the least stressful practice for capture of endangered Turks and Caicos Rock Iguanas Cyclura carinata
Authors: Colosimo Giuliano , Montemuro Gwyneth , Lewbart Gregory A. , Gentile Gabriele , Gerber Glenn P.
Published: April 2024

As the analysis of blood metabolites has become more readily accessible thanks to the use of point-of-care analyzers, it is now possible to evaluate stress level of wild animals directly in the field. Lactate is receiving much attention as a good stress level proxy in individuals subjected to capture, manual restraint, and data sampling in the wild, and appropriate protocols to maintain lactate values low should be preferred. In this study we compare how two different capture methodologies, hand grab vs. noose pole, affect the variation of blood lactate values in Cyclura carinata iguanas when captured for sampling. We used blood lactate concentration, measured immediately upon- and 15 min after-capture, as a proxy for stress level. While the primary goal of this work is to determine the least stressful capture methodology to be favored when sampling this and other wild iguanas, we also evaluated additional baseline physiological parameters relevant to the health and disease monitoring for this species. Our results show that while initial lactate values level-out in sampled individuals after 15 min in captivity, regardless of the capture methodology, rock iguanas captured by noose pole showed significantly higher lactate concentration and increased heartbeat rate immediately after capture. While the overall health evaluation determined that all analyzed individuals were in good health, based on our results we recommend that, when possible, hand capture should be preferred over noose pole when sampling wild individuals.
Correlation of Glycaemic Control and BMI with Renal Profile in Type 2 Diabetic Patients with and without Non Alcoholic Fatty Liver Disease: A Case-control Study
Authors: Padvi Preeti Vijaysing , More Kavita , Rai Sandeep
Published: April 2024

Introduction: Obesity is a risk factor for the development of diabetes, and these two are directly implicated in an individual’s risk of developing Non Alcoholic Fatty Liver Disease (NAFLD), which is a major factor in Metabolic Syndrome (MS). NAFLD and Type 2 Diabetes Mellitus (T2DM) are known to frequently coexist and act synergistically to elevate the risk of hepatic as well as extrahepatic complications. Aim: To determine the levels of renal profile, electrolytes, Glycosylated Haemoglobin (HbA1c), and Body Mass Index (BMI) in T2DM patients with and without NAFLD, as well as in control subjects, and to assess the correlation of BMI and HbA1c with renal profile and electrolytes in T2DM patients with and without NAFLD. Materials and Methods: This case-control study was conducted in the Department of Biochemistry and the Diabetes Speciality Clinic in the Department of General Medicine at MGM Medical College and Hospital, Navi Mumbai, Maharashtra, India, from December 2021 to March 2023. The study included a total of 90 subjects divided into three groups (30 in each): Group 1-Control, Group 2-T2DM with NAFLD, and Group 3-T2DM without NAFLD. Aseptic blood collection was performed, and Renal Function Test (RFT), electrolytes, and HbA1c levels were analysed. Group comparisons were done using unpaired t-tests, and correlation analysis was conducted using Pearson’s correlation with Statiistical Package for Social Sciences (SPSS) software version 25.0. Results: The authors found that 57% of the total enrolled population were female, while the remaining 43% were male, with a mean age of (49.03±5.09) years. Mean levels of HbA1c (9.55±1.78, 8.61±1.42%), BMI (28.84±4.19, 23.51±2.09) kg/m², Urea (31.62±6.28, 33.02±5.11) mg/dL, Creatinine (1.29±0.18, 1.36±0.10) mg/dL, and Uric acid (6.74±1.19, 6.01±0.83) mg/dL were found to be significantly higher in Group 2 and Group 3, respectively, compared to controls. A positive significant correlation of BMI with uric acid, HbA1c with urea, creatinine, and uric acid in Group 2 and 3 was observed. However, no derangement was observed concerning electrolytes in any group. Conclusion: The correlation of urea, creatinine, and uric acid with HbA1c provides the authors with information on impaired renal function in diabetic as well as NAFLD participants. Hyperuricaemia in these individuals can aggravate the risk of T2DM and NAFLD, leading to its progression in Non Alcoholic Steatohepatitis (NASH), respectively.
Cardiopulmonary Rehabilitation along with Inspiratory Muscle Training to Improve Aerobic Capacity in Athletic Patient Following Atrial Septal Defect Closure: A Case Report
Authors: Chobisa Chitrakshi , Vardhan Vishnu , Baheti Nandini
Published: April 2024

An Atrial Septal Defect (ASD) is a type of congenital heart defect in which there is an abnormal opening between the two atria. Hereby, the authors present a case report that describes a 16 mm diameter ostium secundum ASD that was diagnosed in an 18-year-old female district badminton player who came to casualty with chief complaints of difficulty in breathing while playing and an episode of syncope. After undergoing ASD closure surgery, cardiovascular rehabilitation and PowerBreathe deviceassisted inspiratory muscle training were initiated. The present study emphasises the value of interdisciplinary treatment, including physiotherapy, to enhance overall functional status and respiratory function in the management of congenital cardiac disorders. Significant improvements were observed in pain, exercise ability, anxiety, and weariness, according to the end measures. In addition to highlighting the importance of these treatments in the postoperative care of patients with congenital heart disorders, the debate sheds light on the advantages of inspiratory muscle training and its possible effects on cardiopulmonary function. The present comprehensive approach, which combines pharmacological, surgical, and physical therapy treatments, has shown to improve patient outcomes and create opportunities for future advancements in the field of congenital cardiac disease management.
Does Employee Engagement Strategy Matter? An Intervention to Improve Job Embeddedness of Employees in the Private Higher Education Institutions
Authors: Yuwono Wiji , Qamari Ika Nurul , Nuryakin .
Published: April 2024

Private universities face a high turnover rate. The employment issue is compounded by factors such as long working hours, heavy workloads, customer aggression, stress levels, uncomfortable work schedules, and other work-related challenges commonly faced by employees in these institutions. Addressing this employment issue involves the concepts of job embeddedness and employee engagement. This study aims to understand the factors that can enhance job embeddedness and explore the mediating role of employee engagement strategy in the relationship between work-family conflict, work overload, and job embeddedness. The study involved 205 faculty members from private universities as respondents. This study use a quantitative method and Structural Equation Modeling Partial Least Squares (SEM PLS) was used for analysis. The findings reveal that work overload and work-family conflict have a significant negative impact on both employee engagement strategy and job embeddedness. Conversely, employee engagement strategy positively influences job embeddedness. Moreover, employee engagement strategy mediates the relationship between work-family conflict, work overload, and job embeddedness.
A Randomized Trial of Honey Versus Povidone Iodine Dressings: Pain Profile of Wagner Grade 2 Diabetic Foot Ulcers
Authors: Iwunze Charles I. , Iwunze Ezinne C.
Published: April 2024

Diabetic foot ulcers (DFU), a chronic disorder of public health importance arise from pathologic changes following abnormal glucose metabolism. Wound dressing is vital to DFU management and is designed to promote healing and relieve pain among other roles. Pain associated with chronic wounds can delay healing, reduce quality of life, and affect mental health.
This study evaluates the effect of honey and povidone iodine-based dressings on the severity of pain associated with Wagner grade 2 DFU.
Study Design:  This was a randomized controlled trial on the pain-modulating effects of honey and povidone iodine dressings on Wagner grade 2 DFU using the visual analogue scale (VAS) at the University of Port Harcourt Teaching Hospital (UPTH), Port Harcourt over a year duration.
Methodology: We included 30 patients (17 males; age range 47-65 years) with Wagner grade 2 diabetic foot ulcers. Data on socio-demographics, BMI, HbA1c, ulcer etiology and site distribution, VAS for pain intensity, wound exudate characteristics and extent of healing were obtained and analyzed using Statistical Package for the Social Sciences (SPSS) 20.0. A p-value <0.05 was considered significant.
Results: The median VAS pain score was 2.0 and 3.0 for the honey and povidone iodine dressing groups respectively (p-value=0.724) in week 1, then 1.0 and 2.0 for the honey and povidone iodine dressing groups respectively and (p-value=0.041) in week 3. By week 5, all ulcers in the honey group were healed, and the lone persistent ulcer in the povidone group had a 1.0 VAS score by week 6.
Conclusion: Honey dressings are associated with less wound pain over the course of treatment compared to povidone iodine dressing in the treatment of Wagner 2 DFU.
CO\(_2\) and Climate Change: Unveiling the Missing Experimental Evidence
Authors: Pustišek Andrej
Published: April 2024

Human activities releasing greenhouse gases are identified as dominant contributors to the observed climate change including global warming and its acceleration. The consequences for humanity are predicted to be severe. Therefore, to mitigate global warming, significant efforts are being devoted to reducing CO2 emissions and stabilizing (or even reducing) atmospheric CO2 concentration. This enormous endeavor of ‘decarbonization’ comes with substantial costs, running into trillions of USD in Western countries alone.

Fundamentally, the entirety of endeavors, actions, and outcomes hinges upon the central hypothesis stating that the increase of CO2 concentration from approximately 0.03% to more than 0.04% causes a noticeable temperature rise. Given the paramount significance of this hypothesis, the generally accepted rules of science would necessitate rigorous scrutiny for substantiation. Such substantiation is typically provided by an experimental evidence.

Yet, surprisingly according to the results of this research, exactly this essential experimental evidence supporting the central hypothesis seems to be lacking, not fully adhering to fundamental principles of scientific analysis. Consequently, robust experimental evidence must be presented to substantiate the hypothesis, as the failure to do so would necessitate a reassessment of the emphasis on CO2 emissions reduction as the primary solution to climate change.
Determinants of Equine Foot Diseases in Assam, India
Authors: Deka Deepjyoti , Sarma Kushal K. , Kachari Jodumoni , Rajkhowa Jiten , Barman N. N. , Arif Syed A. , Das T.
Published: April 2024

Aim: Equine foot problems is crucial for maintaining the overall health and performance of horses, as these issues can significantly impact their mobility, comfort, and quality of life. A lot of studies have been conducted in these aspects, however, no such detail history have been reported from this part of the country. The present study deals with the prevalence of various foot disorders in riding horses and their correlation to the type of ration provided, work engagement and immediate environmental conditions like equine housing patterns. The study also tries to understand the correlations between the prevalence of diverse foot ailments and the temporal variations specific to the region.
Study Design: A cross-sectional observational work designed to collect data regarding various foot affections prevalent in the equine population of selected locations of Assam, India.
Place of Study:4th Assam Police Battalion, Kahilipara, North-East Police Academy, Barapani, 47 Assam NCC Squadron, Khanapara and SSB horse unit, Debendra Nagar, Tezpur.
Methodology: Surveys were conducted to assess the prevalence of hoof-related conditions in horses through interviews, physical examinations and radiographic examinations. Etiological factors were investigated by recording the history of affected animals, including ration type, quantity, foot care practices.
Results: Thirty-five (71.42%) exhibited various foot lesions while the remaining 14 horses were detected with minor cuts/abrasions. The Prevalence of foot afflictions was found to be higher during the summer (42.86%) in comparison to the winter (28.57%). The spectrum of foot ailments documented includes hoof overgrowth (57.14%), hoof cracks (20%), thrush (8.57%), suppurative sole conditions (5.71%), quittor (2.86%), laminitis (2.86%) and bulb fibromas (2.86%). The occurrences of various types of foot afflictions were elevated in equine enclosures with concrete flooring (94.29%), as opposed to sand flooring (5.71%). Hematological analyses indicated significant (P<0.05) alterations in various blood parameters during both summer and winter for both healthy and affected equines in Hb and mean values of Red blood cells (RBC) and White Blood cells (WBC) except for neutrophils. Biochemical assessments revealed an increase in mean values of serum creatinine, creatine kinase (CK) and alkaline phosphatase (ALP) in affected horses, though aspartate amino transferase (AST) levels remained unaffected.
Conclusion: The multifaceted interplay between equine health, housing conditions, dietary patterns, and seasonal factors in the prevalence of foot disorders in stabled horses.
Rich Phase Behavior in a Supramolecular Conducting Material Derived from an Organogelator
Authors: Puigmartí‐Luis Josep , Laukhina Elena E. , Laukhin Vladimir N. , Pérez del Pino Ángel , Mestres Narcis , Vidal‐Gancedo José , Rovira Concepció , Amabilino David B.
Published: February 2009

Organic conducting fiber‐like materials hold great promise for the development of nanowires that can act as connections in miniature electronic devices, as an alternative to inorganic nanometer scale structures. This article presents a conducting organic tetrathiafulvalene‐based supramolecular material which possesses a rich phase behavior with different packing of the molecules in the different forms, evidenced by electron spin resonance (ESR) spectroscopy. The distinct phases of conducting nanofibers can be easily fabricated through the temperature control of their preparation process from a xerogel by doping with iodine vapors. A total of four conducting phases have been identified conclusively using ESR spectroscopy as the key analytical tool. Three of the phases show a good long‐term stability and areas in which the
I–V curves have ohmic behavior when studied by current sensing (conducting) AFM. They offer promise for applications where electrical nanometer scale connections are required.
Controlled Deposition of Crystalline Organic Semiconductors for Field‐Effect‐Transistor Applications
Authors: Liu Shuhong , Wang Wechung Maria , Briseno Alejandro L. , Mannsfeld Stefan C. B. , Bao Zhenan
Published: February 2009

The search for low‐cost, large‐area, flexible devices has led to a remarkable increase in the research and development of organic semiconductors, which serve as one of the most important components for organic field‐effect transistors (OFETs). In the current review, we highlight deposition techniques that offer precise control over the location or in‐plane orientation of organic semiconductors. We focus on various vapor‐ and solution‐processing techniques for patterning organic single crystals in desired locations. Furthermore, the alignment of organic semiconductors via different methods relying on mechanical forces, alignment layers, epitaxial growth, and external magnetic and electric fields are surveyed. The advantages, limitations, and applications of these techniques in OFETs are also discussed.
Homobimetallic Ruthenium Vinylidene, Allenylidene, and Indenylidene Complexes: Synthesis, Characterization, and Catalytic Studies
Authors: Sauvage Xavier , Borguet Yannick , Zaragoza Guillermo , Demonceau Albert , Delaude Lionel
Published: February 2009

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Four homobimetallic ruthenium‐(p‐cymene) complexes bearing a tricyclohexylphosphine ligand and polyunsaturated carbon‐rich fragments were obtained via a vinylidene‐allenylidene‐indenylidene cascade pathway from the ethylene complex [(p‐cymene)Ru(μ‐Cl)3RuCl(PCy3)(η2‐C2H4)] (7a). All the products were isolated and fully characterized by IR and NMR spectroscopies. The molecular structure of the indenylidene complex 11 was determined by X‐ray crystallographic analysis. The catalytic activity of the four complexes was probed in various types of olefin metathesis reactions and compared with those of a related homobimetallic ruthenium‐benzylidene complex, as well as first, second, and third generation monometallic Grubbs catalysts. In the ring‐closing metathesis (RCM) of diethyl diallylmalonate, the homobimetallic ruthenium‐indenylidene complex 11 outperformed all the ruthenium‐benzylidene complexes under investigation and was only slightly less efficient than its monometallic parent. Cross‐metathesis experiments with ethylene showed that deactivation of ruthenium‐benzylidene or indenylidene complexes was due to the rapid bimolecular decomposition of methylidene active species into ethylene complex 7a. Vinylidene and allenylidene complexes were far less efficient catalyst precursors for ring‐opening metathesis polymerization (ROMP) or RCM and remained inert under an ethylene atmosphere. Their catalytic activity was, however, substantially enhanced upon addition of an acidic co‐catalyst that most likely promoted their in situ transformation into indenylidene species. Due to its straightforward synthesis and high metathetical activity, homobimetallic ruthenium‐indenylidene complex 11 is a valuable intermediate for the preparation of the Hoveyda–Grubbs catalyst [Cl2Ru(PCy3)(CH‐o‐O‐i‐PrC6H4)] via stoichiometric cross‐metathesis with 2‐isopropoxystyrene. The procedure did not require any sacrificial phosphine and the transition metal not incorporated into the final product was easily recovered and recycled at the end of the process.
The role of the brain‐derived neurotrophic factor (BDNF) val66met variant in the phenotypic expression of obsessive‐compulsive disorder (OCD)
Authors: Katerberg Hilga , Lochner Christine , Cath Danielle C. , de Jonge Peter , Bochdanovits Zoltán , Moolman‐Smook Johanna C. , Hemmings Sîan M.J. , Carey Paul D. , Stein Dan J. , Sondervan David , Boer Johan A. den , van Balkom Anton J.L.M. , Polman Annemiek , Heutink Peter
Published: February 2009

Evidence suggests that the Val66Met variant of the brain‐derived neurotrophic factor (BDNF) gene may play a role in the etiology of Obsessive‐Compulsive Disorder (OCD). In this study, the role of the BDNF Val66Met variant in the etiology and the phenotypic expression of OCD is investigated. Associations between the BDNF Val66Met variant and OCD, obsessive‐compulsive symptom dimensions, Yale‐Brown Obsessive Compulsive Scale (YBOCS) severity scores, age of onset and family history of obsessive‐compulsive symptoms were assessed. The BDNF Val66Met variant was genotyped in 419 patients with sub‐/clinical OCD and 650 controls. No differences in allele or genotype frequency were observed between cases and controls. In females with OCD, the Met66Met genotype was associated with later age of onset and a trend for a negative family history, whereas the Val66Val genotype was associated with a trend for lower YBOCS severity scores. Item‐level factor analysis revealed six factors: 1) Contamination/cleaning; 2) Aggressive obsessions/checking; 3) Symmetry obsessions, counting, ordering and repeating; 4) Sexual/religious obsessions; 5) Hoarding and 6) Somatic obsessions/checking. A trend was found for a positive association between Factor 4 (Sexual/religious obsessions) and the BDNF Val66Val genotype. The results suggest that BDNF function may be implicated in the mediation of OCD. We found that for the BDNF Met66Met genotype may be associated with a milder phenotype in females and a possible role for the BDNF Val66Val genotype and the BDNF Val66 allele in the sexual/religious obsessions. © 2009 Wiley‐Liss, Inc.
Autoantibodies against β‐amyloid are common in Alzheimer's disease and help control plaque burden
Authors: Kellner Alexander , Matschke Jakob , Bernreuther Christian , Moch Holger , Ferrer Isidro , Glatzel Markus
Published: February 2009

Objective

Active or passive immunization of Alzheimer's disease (AD) patients leads to targeting of β‐amyloid plaques by immunoglobulins (IgG) and their subsequent removal by microglia. Here, we investigate whether naturally occurring autoantibodies to β‐amyloid contribute to β‐amyloid plaque removal in nonimmunized AD patients.

Methods

We generated an AD tissue microarray with 2,325 tissue specimens from 3 defined central nervous system regions of 48 AD patients and 48 age‐matched control patients. Absolute quantification of β‐amyloid, β‐amyloid plaque‐bound IgG, and phagocytic, resting, and activated microglia and microhemorrhages was done using a standardized, highly reproducible scoring system.

Results

The majority of neuritic plaques are decorated by IgG. AD patients with prominently IgG‐labeled neuritic plaques have a significantly reduced plaque burden and an increase in phagocytic microglia, yet no increase in microhemorrhages.

Interpretation

Autoantibodies directed against β‐amyloid are common in AD patients and may contribute in controlling plaque burden. Ann Neurol 2009;65:24–31
Genetic determinants of hair color and parkinson's disease risk
Authors: Gao Xiang , Simon Kelly C. , Han Jiali , Schwarzschild Michael A. , Ascherio Alberto
Published: February 2009

Objective

A history of melanoma is associated with increased risks for Parkinson's disease (PD). We examined whether hair color, one of the most important phenotypes of pigmentation and a risk factor for melanoma, was associated with PD risk in the Health Professionals Follow‐up Study (HPFS; 1986–2002) and the Nurses' Health Study (NHS; 1980–2002).

Methods

We included 38,641 men and 93,661 women who were free of PD at baseline. Information on natural hair color in early adulthood (age 18–21 years) was assessed via a questionnaire. We also conducted a case–control study (298 PD cases) nested in these two cohorts to examine the association between the melanocortin1‐receptor Arg151Cys polymorphism and PD risk. Relative risks (RRs) were estimated using Cox proportional hazards models in the cohort analyses and conditional logistic regression in the nested case–control study.

Results

PD risk increased with decreasing darkness of hair color. Pooled RRs for PD were 1 (reference), 1.40, 1.61, and 1.93 (95% confidence interval, 1.1–3.4) for black, brown, blond, and red hair, respectively, after adjusting for age, smoking, ethnicity, and other covariates. The associations between hair color and PD were particularly strong for relative younger onset of PD (<70 yr) (adjusted RR for red vs black hair = 3.83; 95% confidence interval, 1.7–8.7). In the case–control study, participants with Cys/Cys genotype, which was associated with red hair, had a greater PD risk, relative to the Arg/Arg genotype (adjusted RR, 3.15; 95% confidence interval, 1.1–9.4).

Interpretation

These findings suggest a potential role of pigmentation in PD. Ann Neurol 2009;65:76–82
Pelizaeus–Merzbacher–Like disease presentation of MCT8 mutated male subjects
Authors: Vaurs‐Barrière Catherine , Deville Marlène , Sarret Catherine , Giraud Geneviève , Des Portes Vincent , Prats‐Viñas José‐Maria , De Michele Giuseppe , Dan Bernard , Brady Angela F. , Boespflug‐Tanguy Odile , Touraine Renaud
Published: February 2009

Pelizaeus–Merzbacher Disease is an X‐linked hypomyelinatiing leukodystrophy. We report mutations in the thyroid hormone transporter gene MCT8 in 11% of 53 families affected by hypomyelinating leukodystrophies of unknown aetiology. The 12 MCT8 mutated patients express initially a Pelizaeus–Merzbacher‐Like disease phenotype with a latter unusual improvement of magnetic resonance imaging white matter signal despite absence of clinical progression. This observation underlines the interest of determining both free T3 and free T4 serum concentrations to screen for MCT8 mutations in young patients (<3 y) with a severe Pelizaeus–Merzbacher‐Like disease presentation or older severe mentally retarded male patients with “hypomyelinated” regions. Ann Neurol 2009;65:114–118
“Covalent Capture”: Verschmelzung von kovalenter und nichtkovalenter Synthese
Authors: Prins Leonard J. , Scrimin Paolo
Published: February 2009

Es genügt, die passenden Moleküle zusammenzubringen, um die irreversible oder reversible Bildung einer kovalenten Bindung einzuleiten. Die Covalent‐Capture‐Strategie, bei der eine supramolekulare Wechselwirkung der kovalenten Bindungsbildung vorausgeht (siehe Schema), tritt bei unterschiedlichsten biologischen und synthetischen Systemen in Erscheinung und kann für zahlreiche Anwendungen genutzt werden.

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Dieser Aufsatz befasst sich mit Molekülen auf der Suche nach einem geeigneten Partner, mit dem sie eine Verbindung eingehen können. Ob das erste Treffen in einer festen Bindung endet, hängt von vielen Faktoren ab, z. B. von der Vereinbarkeit von Größe, Form und Reaktivität, von der geeigneten Anordnung der reaktiven Gruppen und von den Einflüssen des Mediums. In gewisser Weise spielt der Chemiker die Rolle des Zeremonienmeisters, der mit einer erfolgreichen Verbindung belohnt wird. Giottos Gemälde “Die Vermählung Mariä” soll die hierbei beteiligten Prinzipien der supramolekularen Chemie versinnbildlichen.
Ein substituentenfreier Galliumligand durch Hydrogenolyse von koordiniertem GaCp*: Synthese und Struktur des hoch fluktionalen [Ru2(Ga)(GaCp*)7(H)3]
Authors: Cadenbach Thomas , Gemel Christian , Schmid Rochus , Halbherr Markus , Yusenko Kirill , Cokoja Mirza , Fischer Roland A.
Published: February 2009

Der vollständige Ligandenaustausch durch Hydrogenolyse von [Ru(η4‐cod)(η6‐cot)] in Gegenwart von GaCp* führt unter milden Bedingungen zu der Titelverbindung, in der ein „nacktes“ Galliumatom zwei Rutheniumzentren verbrückt (siehe Bild: C weiß, Ga blau, Ru rot). Dieser Cluster kann als abgefangenes Intermediat auf dem Weg zu gemischtmetallischen Nanopartikeln angesehen werden. cot=1,3,5‐Cyclooctatrien; cod=1,5‐Cyclooctadien; Cp*=C5Me5.

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Biomimetic Total Synthesis of (±)‐Pallavicinolide A
Authors: Dong Jia‐Qiang , Wong Henry N. C.
Published: February 2009

Vom Teil zum Ganzen: Die erste Totalsynthese des natürlich vorkommenden Diterpens Pallavicinolid A ist gelungen. Besonders hervorzuheben sind drei biomimetische Umwandlungen: eine basenunterstützte Grob‐Fragmentierung, eine Singulettsauerstoff‐Oxidation und eine intramolekulare Diels‐Alder‐Cycloaddition.

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Biomimetic Total Synthesis of (±)‐Pallavicinolide A
Authors: Dong Jia‐Qiang , Wong Henry N. C.
Published: February 2009

Piecing it together: The first total synthesis of naturally occurring diterpene pallavicinolide A was achieved. Notable features are highlighted by three key biomimetic transformations: a base‐promoted Grob fragmentation, a singlet oxygen oxidation, and an intramolecular Diels–Alder cycloaddition.

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Preparation and characterization of chloroacetylated polystyrene‐supported zinc complexes and evaluation of their catalytic activities for the synthesis of 1,1‐diacetates
Authors: Wang Liang , Cai Chun
Published: February 2009

Zinc chloride was immobilized onto chloroacetylated polystyrene via different linkages to afford polymer‐supported Lewis acid catalysts. The functionalized beads and the immobilized catalysts were characterized by elemental analysis, Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, and inductively coupled plasma and thermal analysis. The reaction of aldehydes with anhydride in the presence of the supported catalysts was investigated. The effects of various parameters, including the solvent, amount of catalyst, and temperature, on the reaction were also studied. We found that the reaction proceeded smoothly under solvent‐free conditions at room temperature and afforded the corresponding acylals in good yields. Moreover, the catalysts could be recovered easily and reused several times without a significant loss in activity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis, swelling behaviors, and slow‐release characteristics of a guar gum‐g‐poly(sodium acrylate)/sodium humate superabsorbent
Authors: Wang Wenbo , Wang Aiqin
Published: February 2009

Superabsorbents used in agricultural and ecological projects with low‐cost, slow‐release fertilizers and environmentally friendly characteristics have been extensively studied. The use of a natural polymer as the matrix and then further polymerization with some functional material has become the preferred method. In this work, with natural guar gum (GG), partially neutralized acrylic acid, and sodium humate (SH) as the raw materials, ammonium persulfate as the initiator, and N,N′‐methylenebisacrylamide (MBA) as the crosslinker, GG‐g‐poly(sodium acrylate) (PNaA)/SH superabsorbents were synthesized through a solution polymerization reaction and were characterized with Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. The effects of the SH content and MBA concentration on the water absorbency were investigated. The results showed that the introduction of SH into the GG‐g‐PNaA system could improve the water absorbency, swelling rate, pH‐resistant property, and reswelling capability, and the superabsorbent containing 15 wt % SH had the highest water absorbency of 532 g/g of sample in distilled water and 62 g/g of sample in a 0.9 wt % NaCl solution. The slow release in water and water retention in sandy soil tests revealed that the superabsorbent could act as a fertilizer as well as an effective water‐saving material for agricultural applications. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Quantitative effects of synthesis conditions on oil absorptive properties of oil gels based on EPDM/4‐tert‐Butylstyrene
Authors: Wu Bo , Zhou Mei H.
Published: February 2009

The oil absorption properties of porous polymeric gels are dependent on their synthesis conditions. In this work, we have investigated whether it is feasible to find a quantitative relationship between the synthesis conditions of porous poly(EDPM/4‐tert‐Butylstyrene) gels and their behavior in the kerosene absorption through a factorial design of experiments. For this purpose, a series of such oil gels have been synthesized in toluene with various divinylbenzene (DVB) and EPDM contents. The kerosene absorbency and kerosene‐absorption kinetics of oil gels were determined. Finally, empirical models correlating the synthesis conditions with the kerosene absorbency (Qeq) and kerosene‐absorption kinetic constant (K) were calculated; it was observed that lower the DVB concentration and higher the EPDM fraction in the monomeric mixtures, the higher the kerosene absorbency. With regard to the kerosene‐absorption kinetics, the largest K value was achieved with the lowest DVB concentration and the highest EPDM fraction. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Improved processing behaviors and mechanical properties of polyolefin elastomer blends prepared by ultrasound‐assisted extrusion
Authors: Jiang Genjie , Wu Hong , Xie Tingting , Guo Shaoyun
Published: February 2009

To improve the processability of ethylene‐α‐olefin copolymers (POE), POE and POE/polystyrene (PS) blends were extruded in the presence of ultrasound. On the one hand, the effect of ultrasound on the die pressure drop, extrudate productivity, melt viscosity of POE, and the processing behaviors of POE and POE/PS (80/20) blend were studied. The results showed that with increasing ultrasound power, the die pressure and melt‐apparent viscosity of POE decreased whereas the productivity of POE extrudates increased, then the processability of POE was greatly improved. On the other hand, the effects of ultrasound on the morphology, rheological, and mechanical properties of POE/PS (80/20) blend were studied. Capillary rheological results showed that the merger of ultrasound and the addition of PS showed a synergistic improvement of processability of POE. From morphological observation and rheological analysis, the compatibility of the blend was also improved in the presence of 200W ultrasound. As a result, the stress at break of compatibilized POE/PS (80/20) blend increased from 9.2 to 11.0 MPa, and the dynamic storage modulus increased at experimental temperature range, indicating that the mechanical properties of POE/PS blends can be improved by ultrasound‐assisted extrusion. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Tensile properties, barrier properties, and biodegradation in soil of compression—Molded gelatin‐dialdehyde starch films
Authors: Martucci J. F. , Ruseckaite R. A.
Published: February 2009

Glycerol (Gly)‐plasticized gelatin (Ge) films crosslinked with dialdehyde starch (DAS) as environmentally friendly crosslinking agent were successfully produced by compression molding, demonstrating the capacity of gelatin of being transformed into films by using thermoplastic processes. The effect of DAS content on the color, light transmission, total soluble matter (TSM), water uptake (WU), water vapor permeability (WVP), oxygen permeability (OP) as well as biodegradability during soil burial was investigated. The addition of up to 10 wt % DAS (Ge‐10DAS) generated transparent films, with reduced TMS, WU, WVP, and OP values but higher extensivity than the uncrosslinked counterpart. Further incorporating DAS into plasticized‐gelatin matrix conducted to phase separation with detrimental effect of transparency and tensile properties. DAS‐containing films degraded at slow rate than the uncrosslinked counterpart, suggesting that biotic attack during soil burial is restricted by covalent crosslinking points induced by DAS. Ge‐10DAS films lost about 28% of their initial mass within the first 8 days of exposure to degrading medium; therefore, the material can be classified as rapidly degradable. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Nanosilica as dry bonding system component and as reinforcement in short nylon‐6 fiber/natural rubber composite
Authors: Mathew Leny , Narayanankutty Sunil K.
Published: February 2009

Nanoscale silica was synthesized by acid hydrolysis of sodium silicate using dilute hydrochloric acid under controlled conditions. The synthesized silica was characterized by SEM, BET adsorption, and XRD. The particle size of silica was calculated to be 13 nm from the XRD results and the surface area was found to be 295 m2/g by BET method. This synthesized nanosilica was used in place of conventional silica in HRH (hexamethylenetetramine, resorcinol and silica) bonding system for natural rubber/Nylon‐6 short fiber composite. Nanosilica was also used as reinforcing filler in natural rubber/Nylon‐6 short fiber hybrid composite. Mechanical, thermal, and dynamic mechanical properties of the composites were evaluated. The introduction of the nanosilica in hybrid composites improved the tensile strength, modulus, and tear strength through improved interaction with the matrix which is facilitated by the higher surface area. Abrasion loss and hardness were also better for the nanosilica composites. Resilience and compression set were adversely affected. The hybrid composites showed anisotropy in mechanical properties. Peak rate of thermal decomposition decreased and temperature of initiation of thermal degradation increased with silica content, indicating improved thermal stability of the hybrid composites. The storage modulus and loss modulus showed two‐stage dependence on frequency at higher fiber loading. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Thermal and morphological properties of SA/HPMC blends
Authors: Mruthyunjaya Swamy T. M. , Ramaraj B. , Siddaramaiah
Published: February 2009

Sodium alginate (SA) was blended with varying amounts of hydroxypropyl methylcellulose (HPMC) viz., 10, 20, and 30 wt % by solution casting process. Thus, the obtained blends were characterized by using different analytical techniques such as differential scanning calorimetry (DSC), thermogravimetric analyzer (TGA), Fourier transform infrared spectroscopy (FTIR), and scanning electron microcopy (SEM). FTIR studies reveal the hydrogen bond formation between hydroxyl groups of SA and HPMC polymer chains. DSC analysis shows single glass transition temperature (Tg) for SA/HPMC blends indicating compatibility and physical interaction between SA and HPMC polymer chains. TGA analysis indicates variation of thermal stability of SA with change in compositions of HPMC. SEM studies reveal uniform distribution of second phase in the blends. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
EMI shielding: Methods and materials—A review
Authors: Geetha S. , Satheesh Kumar K. K. , Rao Chepuri R. K. , Vijayan M. , Trivedi D. C.
Published: February 2009

The growth in the application of electronic devices across a broad spectrum of military, industrial, commercial and consumer sectors has created a new form of pollution known as noise or radio frequency interference (RFI) or electromagnetic radiation or electromagnetic interference (EMI) that can cause interference or malfunctioning of equipment. Therefore, there is a greater need for the effective shielding of components from its adverse effects. This review surveys the shielding materials like metals, conducting plastics and conducting polymers for the control of electromagnetic radiations. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Catalysis of ethylene to linear low‐density polyethylene with iron‐based diimine complex immobilized on calcosilicate and silica‐supported rac‐Et(Ind)2ZrCl2
Authors: Yan Feng‐Wen , Xu Hao , Guo Cun‐Yue , Zhang Ming‐Ge , Zhang Xiao‐Hui , Yang Hai‐Jian , Yuan Guo‐Qing
Published: February 2009

Iron‐based diimine complex was immobilized on calcosilicate (CAS‐1) to form heterogeneous precatalyst, which oligomerized ethylene to α‐olefins even without the use of aluminum alkyl compounds as activators. The α‐olefins, upon the catalysis of another catalyst, i.e., silica‐supported rac‐Et(Ind)2ZrCl2, copolymerized with ethylene to produce linear low‐density polyethylene (LLDPE). The copolymerization reactions could be performed with the addition of triethylaluminum alone because of the introduction of methylaluminoxane to CAS‐1 and silica during the supporting process. In addition to the formation of more α‐olefins with lower molar mass, the layered structure of CAS‐1 acted well in the controlled release of α‐olefins in the copolymerization process. The simultaneous employment of the aforementioned two catalysts hence resulted in high catalytic activities, smooth kinetic process, well‐regulated branching degree, higher molecular weights (Mn), improved thermal stability, and better morphology of the LLDPE obtained. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Historic marine invertebrate species inventory: case study of a science baseline towards establishing a marine conservation area
Authors: Sloan N.A. , Bartier P.M.
Published: February 2009

Assessing species diversity is a basic requirement for conservation, and protecting biodiversity is a major goal of marine area conservation.

A case study is presented on the development of a literature‐based (1870s to 2000), museum collection‐based, georeferenced inventory of marine invertebrate species of the Haida Gwaii (Queen Charlotte Islands) region, Canada.

Database structure and quality assurance are described, along with including indigenous people's words for species towards using traditional knowledge within cooperative marine conservation area management.

The utility of this type of inventory is proposed as a starting point for gathering regional biodiversity knowledge, and facilitating addition of other knowledge types, towards marine area conservation.

Copyright © 2009 John Wiley & Sons, Ltd.
A new presentation and exploration of human cerebral vasculature correlated with surface and sectional neuroanatomy
Authors: Nowinski Wieslaw L. , Thirunavuukarasuu Arumugam , Volkau Ihar , Marchenko Yevgen , Aminah Bivi , Gelas Arnaud , Huang Su , Lee Looi Chow , Liu Jimin , Ng Ting Ting , Nowinska Natalia G. , Qian Guoyu Yu , Puspitasari Fiftarina , Runge Val M.
Published: February 2009

The increasing complexity of human body models enabled by advances in diagnostic imaging, computing, and growing knowledge calls for the development of a new generation of systems for intelligent exploration of these models. Here, we introduce a novel paradigm for the exploration of digital body models illustrating cerebral vasculature. It enables dynamic scene compositing, real‐time interaction combined with animation, correlation of 3D models with sectional images, quantification as well as 3D manipulation‐independent labeling and knowledge‐related meta labeling (with name, diameter, description, variants, and references). This novel exploration is incorporated into a 3D atlas of cerebral vasculature with arteries and veins along with the surrounding surface and sectional neuroanatomy derived from 3.0 Tesla scans. This exploration paradigm is useful in medical education, training, research, and clinical applications. It enables development of new generation systems for rapid and intelligent exploration of complicated digital body models in real time with dynamic scene compositing from highly parcellated 3D models, continuous navigation, and manipulation‐independent labeling with multiple features. Anat Sci Ed 2:24–33, 2009. © 2009 American Association of Anatomists.
Design and development of a new facility for teaching and research in clinical anatomy
Authors: Greene John Richard T.
Published: February 2009

This article discusses factors in the design, commissioning, project management, and intellectual property protection of developments within a new clinical anatomy facility in the United Kingdom. The project was aimed at creating cost‐effective facilities that would address widespread concerns over anatomy teaching, and support other activities central to the university mission–namely research and community interaction. The new facilities comprise an engaging learning environment and were designed to support a range of pedagogies appropriate to the needs of healthcare professionals at different stages of their careers. Specific innovations include integrated workstations each comprising of a dissection table, with removable top sections, an overhead operating light, and ceiling‐mounted camera. The tables incorporate waterproof touch‐screen monitors to display images from the camera, an endoscope or a database of images, videos, and tutorials. The screens work independently so that instructors can run different teaching sessions simultaneously and students can progress at different speeds to suit themselves. Further, database access is provided from within an integrated anatomy and pathology museum and display units dedicated to the correlation of cross‐sectional anatomy with medical imaging. A new functional neuroanatomy modeling system, called the BrainTower®, has been developed to aid integration of anatomy with physiology and clinical neurology. Many aspects of the new facility are reproduced within a Mobile Teaching Unit, which can be driven to hospitals, colleges, and schools to provide appropriate work‐based education and community interaction. Anat Sci Ed 2:34–40, 2009. © 2009 American Association of Anatomists.
Impact of license choice on Open Source Software development activity
Authors: Colazo Jorge , Fang Yulin
Published: February 2009

The Open Source Software (OSS) development model has emerged as an important competing paradigm to proprietary alternatives; however, insufficient research exists to understand the influence of some OSS project characteristics on the level of activity of the development process. A basic such characteristic is the selection of the project's software license. Drawing upon social movement theory, our study examined the relationship between OSS licenses and project activity. Some OSS licenses include a “copyleft” clause, which requires that if derivative products are to be released, it must be done under the license the original product had. We hypothesize that copylefted licenses, as opposed to noncopylefted licenses, are associated with higher developer membership and coding activity, faster development speed, and longer developer permanence in the project. To test the hypotheses, we used archival data sources of working OSS projects spanning several years of development time. We discuss practical and theoretical implications of the results as well as future research ideas.
Insights into the relationship between the h‐index and self‐citations
Authors: Gianoli Ernesto , Molina‐Montenegro Marco A.
Published: February 2009

We analyze the publication output of 119 Chilean ecologists and find strong evidence that self‐citations significantly affect the h‐index increase. Furthermore, we show that the relationship between the increase in the h‐index and the proportion of self‐citations differs between high and low h‐index researchers. In particular, our results show that it is in the low h‐index group where self‐citations cause the greater impact.
Long‐term radio behaviour of GPS sources and candidates
Authors: Tornikoski M. , Torniainen I. , Lähteenmäki A. , Hovatta T. , Nieppola E. , Turunen M. , Lainela M. , Valtaoja E. , Aller M.F. , Aller H.D. , Mingaliev M. , Trushkin S.
Published: February 2009

This paper is a summary of the work that our group has done (and recently published in several papers) on long‐term radio variability of GPS sources. We have studied the long‐term (up to 30 years) variability of GPS sources and candidates, with emphasis on the high‐frequency radio domain. Our data sets show that only a relatively small number of these sources retain their convex spectra when they are monitored densely and for long periods of time. The current GPS samples are especially contaminated by small, beamed blazar‐type sources. Also the remaining population with consistently convex GPS‐type spectra seems to be heterogeneous, falling into several subpopulations when their observed properties are used for clustering them through a self‐organizing map (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Parsec‐scale jet in the distant gigahertz‐peaked spectrum quasar PKS 0858–279
Authors: Kovalev Y. Y.
Published: February 2009

The high redshift GPS quasar PKS 0858–279 exhibits the following properties which make the source unusual. Our RATAN‐600 monitoring of 1–22 GHz spectrum has detected broad‐band radio variability with high amplitude and relatively short time scale. In the same time, the milliarcsecond scale structure observed in a snapshot VLBA survey turned out to be very resolved which is not expected from the fast flux density variations. We performed 1.4–22 GHz VLBA observations of this quasar in 2005–2007. It has revealed a core‐jet morphology. A high Doppler factor δ is suggested for the jet, its nature is discussed in this report on the basis of the multi‐frequency VLBA and RATAN data collected. Synchrotron self‐absorption was confirmed to be dominating at low frequencies, the magnetic field strength of the dominating jet feature is estimated of an order of 0.1δ mG (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simultaneous, multi‐frequency, VLA observations of inverted spectrum radio sources
Authors: Partridge B.
Published: February 2009

We selected extragalactic sources with inverted spectra at 1.4 to 5 GHz, and observed ∼250 of them at the VLA at frequencies from 1.4 to 22 GHz and in some cases 43 GHz. Here we summarize the spectral index distributions, and report on polarization measurements and/or upper limits for a subsample of ∼35 sources (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)