bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyhedral Structures with an Odd Number of Vertices: Nine‐Coordinate Metal Compounds
Authors: Ruiz‐Martínez Antonio , Casanova David , Alvarez Santiago 
Published: November 2007

AbstractThe stereochemistry of nine‐coordinate transition‐metal and rare‐earth compounds has been studied by means of continuous shape measures (CShM) and related tools. Several reference nine‐vertex polyhedra have been defined and their minimal distortion interconversion paths established. A theoretical shape map is presented in which the structures can be placed according to their distances in CShM space to the capped square antiprism and the tricapped trigonal prism, which are the most common polyhedra in nine‐coordinate compounds. The structures of almost 2000 metal coordination spheres in molecular and extended solid‐state compounds have been analyzed. Clear stereochemical trends can be established for subsets of these compounds grouped according to the nature of their ligands, which include families of compounds spread along the interconversion paths between the capped square antiprism and the capped cube, or between the tricapped trigonal prism and the tridiminished icosahedron.
Liquid‐Crystalline Rigid‐Core Semiconductor Oligothiophenes: Influence of Molecular Structure on Phase Behaviour and Thin‐Film Properties
Authors: Melucci Manuela , Favaretto Laura , Bettini Christian , Gazzano Massimo , Camaioni Nadia , Maccagnani Piera , Ostoja Paolo , Monari Magda , Barbarella Giovanna 
Published: November 2007

AbstractThe design, synthesis and properties of liquid‐crystalline semiconducting oligothiophenes containing dithienothiophene (DTT), benzothiadiazole (BTZ) and carbazole (CBZ) rigid cores are described. The effect of molecular structure (shape, size and substitution) on their thermal behaviour and electrical properties has been investigated. Polarised optical microscopy (POM) and differential scanning calorimetry (DSC) analyses have revealed highly ordered smectic mesophases for most of the newly synthesised compounds. X‐ray diffraction (XRD) studies performed at various temperatures have shown that the smectic order is retained in the crystalline state upon cooling across the transition temperature, affording cast films with a more favourable morphology for FET applications.
Canadian takeover announcements and the job security of top managers
Authors: Tannous George F. , Cheng Bin 
Published: November 2007

AbstractThis study measures the turnover rate of top managers (Chief Executive Officers or Presidents) in acquisition targets following the public announcements of takeovers in Canada. Turnover rates following the announcements of completed and unsuccessful takeover attempts did not differ from each other but were higher than the norm for CEOs from a control group of nontarget firms. The turnover rate was particularly high for widely‐held firms and negatively correlated with the preannouncement performance of the targets. Overall, results suggest that a major objective of takeovers in Canada is to reduce management failings, inefficiency, and agency costs. Copyright © 2007 ASAC. Published by John Wiley & Sons, Ltd.
Coronary Flow Reserve Is Impaired in Subclinical Hypothyroidism
Authors: Baycan Semra , Erdogan Dogan , Caliskan Mustafa , Pamuk Baris Onder , Ciftci Ozgur , Gullu Hakan , Yildirir Aylin , Guvener Nilgun D. , Muderrisoglu Haldun 
Published: November 2007

AbstractObjectiveAlthough the cardiovascular system is highly sensitive to thyroid hormones, the cardiovascular effects of subtle thyroid dysfunction such as subclinical hypothyroidism (SHT) remain unclear. Therefore, we investigated coronary flow reserve (CFR) reflecting coronary microvascular function in patients with SHT.MethodsFifty subjects with SHT and 30 control subjects with normal serum thyroid hormones and TSH levels were included in this study. Coronary diastolic peak flow velocities were measured at baseline and after dipyridamole infusion. CFR was calculated as the ratio of hyperemic to baseline diastolic peak velocity.ResultsAge, gender, diastolic and systolic blood pressure, body mass index (BMI), serum lipid parameters, and thyroid hormone levels were similar between the groups. Heart rate was significantly lower in the SHT group. Left ventricular diastolic filling parameters were significantly different in the SHT group while other echocardiographic parameters were similar. CFR values were significantly lower in subjects with SHT than in the control group (2.38 ± 0.44 vs. 2.98 ± 0.47, p < 0.0001).ConclusionsThese findings suggest that CFR, which reflects coronary microvascular function, is impaired in patients with SHT. Copyright © 2007 Wiley Periodicals, Inc.
Is Elevated High‐density Lipoprotein Cholesterol Always Good for Coronary Heart Disease?
Authors: Sun Yuhua , Yang Yuejin , Pei Weidong , Wu Yongjian , Zhao Jinglin 
Published: November 2007

AbstractBackgroundHigh‐density lipoprotein (HDL) could enhance inflammation in atherogenesis when inflammatory response is present, and the activity of paraoxonase and antioxidant in HDL in the elderly is significantly decreased. There might be a different role for high‐density lipoprotein cholesterol (HDL‐C) between different age groups in patients with coronary heart disease (CHD).MethodsFor this study, 225 inpatients with CHD (coronary atherosclerosis stenosis ≥ 50% on ≥ 1 major coronary arteries by coronary angiography), and 80 without CHD; 120 resting unstable angina patients, and 68 with stable angina were consecutively recruited. Risk factors were analyzed for CHD and resting unstable angina.ResultsHigh‐density lipoprotein cholesterol in resting unstable angina was higher than that in stable angina (1.24 ± 1.05 versus 1.05 ± 0.29 mmol/L, p = 0.032). After adjustment for age, sex, physical inactivity, hypertension, diabetes, C‐reactive protein, triglycerides, total cholesterol (TC) and low‐density lipoprotein cholesterol (LDL‐C) the adjusted odds ratio (OR) (95% CI) of resting unstable angina was 10.19 (2.18–47.6, p = 0.003) for HDL‐C. Risk factors were further investigated in different age groups. Adjusted OR of CHD associated with HDL‐C in < 55‐year‐old group was 0.09 (0.01–0.66, p = 0.018), in ≥ 55‐year‐old group it was 0.55 (0.08–3.82, p > 0.05). Adjusted OR of resting unstable angina associated with high HDL‐C was 19.24 (2.86–129.4, p = 0.002) in patients aged ≥ 55 years.ConclusionsElevated HDL‐C might be an independent risk factor for resting unstable angina, even though HDL‐C could play a much more important role in protection against coronary stenosis in younger or middle‐aged persons. Copyright © 2007 Wiley Periodicals, Inc.
Importance of Tissue Perfusion in ST Segment Elevation Myocardial Infarction Patients Undergoing Reperfusion Strategies: Role of Adenosine
Authors: Forman Mervyn B. , Jackson Edwin K. 
Published: November 2007

AbstractHigh risk ST segment elevation myocardial infarction (STEMI) patients undergoing reperfusion therapy continue to exhibit significant morbidity and mortality due in part to myocardial reperfusion injury. Importantly, preclinical studies demonstrate that progressive microcirculatory failure (the “no‐reflow” phenomenon) contributes significantly to myocardial reperfusion injury. Diagnostic techniques to measure tissue perfusion have validated this concept in humans, and it is now clear that abnormal tissue perfusion occurs frequently in STEMI patients undergoing reperfusion therapy. Moreover, because tissue perfusion correlates poorly with epicardial blood flow (TIMI flow grade), clinical studies show that tissue perfusion is an independent predictor of early and late mortality in STEMI patients and is associated with infarct size, ventricular function, CHF and ventricular arrhythmias. The mechanisms responsible for abnormal tissue perfusion are multifactorial and include both mechanical obstruction and vasoconstrictor humoral factors. Adenosine, an endogenous nucleoside, maintains microcirculatory flow following reperfusion by activating four well‐characterized extracellular receptors. Because activation of adenosine receptors attenuates the mechanical and functional mechanisms leading to the “no reflow” phenomenon and activates other cardioprotective pathways as well, it is not surprising that both experimental and clinical studies show striking myocardial salvage with intravenous infusions of adenosine administered in the peri‐reperfusion period. For example, a post hoc analysis of the AMISTAD II trial indicates a significant reduction in 1 and 6‐month mortality in STEMI patients undergoing reperfusion therapy who are treated with adenosine within 3 hours of symptoms. In conclusion, adenosine's numerous cardioprotective effects, including attenuation of the “no‐reflow” phenomenon, support its use in high risk STEMI undergoing reperfusion. Copyright © 2007 Wiley Periodicals, Inc.
Reducing Events in Patients with Chronic Heart Failure (REDUCEhf ) Study Design: Continuous Hemodynamic Monitoring with an Implantable Defibrillator
Authors: Adamson Philip B. , Conti Jamie B. , Smith Andrew L. , Abraham William T. , Aaron Mark F. , Aranda, Jr. Juan M. , Baker James , Bourge Robert C. , Warner‐Stevenson Lynne , Sparks Brandon 
Published: November 2007

AbstractBackgroundThe use of implantable cardioverter defibrillators (ICDs) has been proven effective in the prevention of sudden cardiac death (SCD) and constitutes standard of care in appropriate populations. Combining a pressure sensing system with ICD therapy represents the first attempt to provide continuous hemodynamic monitoring using a device previously designed exclusively for SCD protection.MethodsREDUCE is a prospective, multicenter, randomized, single‐blind, parallel‐controlled trial designed to assess the safety of the Chronicle ICD system (single chamber ICD with a hemodynamic monitoring system) and the effectiveness of a management strategy guided by intracardiac pressure information among ICD‐indicated New York Heart Association (NYHA) Class II or III heart failure (HF) patients. Those successfully implanted with a Chronicle ICD will be randomized to the Chronicle group or Control group. All patients will receive optimal medical therapy, but the hemodynamic information from the device will be used to guide patient management only in the Chronicle group. Primary endpoints include freedom from system‐related complications and relative risk reduction of one or more HF‐related events (hospitalizations, and emergency department and urgent care visits requiring intravenous therapy for HF). Approximately 850 patients will be enrolled in at least 75 centers in the United States to accrue the 419 events needed to test the primary effectiveness endpoint. Enrollment began in April 2006, and is expected to end during 2009.ConclusionREDUCE will assess the safety of the Chronicle ICD system and the effectiveness of a patient management strategy based on remote access to continuous intracardiac pressures in reducing HF‐related events. Copyright © 2007 Wiley Periodicals, Inc.
Biodiesel, Rapeseed Oil, Gas‐To‐Liquid, and a Premium Diesel Fuel in Heavy Duty Diesel Engines: Endurance, Emissions and Health Effects
Authors: Krahl Jürgen , Munack Axel , Grope Norbert , Ruschel Yvonne , Schröder Olaf , Bünger Jürgen 
Published: November 2007

AbstractTo investigate influences of fuel design on regulated and non‐regulated emissions of heavy‐duty diesel engines, a Mercedes‐Benz OM 906 Euro 3 engine was run with common diesel fuel (DF), first‐ and second‐generation alternative fuels (Gas‐to‐liquid (GTL) as prototype for biomass‐to‐liquid (BTL)), and blends of these. Secondly, an IVECO (Industrial Vehicles Corporation) Tector F4A Euro 4 test engine equipped with a urea based selective catalytic reduction (SCR) pilot series system was subjected to a 1000 h endurance test using high‐phosphorous (10 ppm) biodiesel. To unveil possible effects on catalyst efficiency, emissions were studied before and after this endurance test by performing European Stationary Cycle (ESC) tests with common DF and biodiesel with high and low phosphorus content. For both engines, the NOx content in the exhaust gas became most critical with respect to the regulated limits. Among non‐regulated emissions, particle size distributions were determined with special focus on ultra fine particles (UFP), which are suspected to induce severe health problems. Additionally, Ames‐tests were carried out to determine the mutagenic potency of particulate matter extracts. Both UFP and mutagenicity appeared to be negatively influenced with blends, biodiesel with high P‐content, and rapeseed oil.
Membrane Bioreactor (MBR) Treatment of Segregated Household Wastewater for Reuse
Authors: Atasoy Elif , Murat Selda , Baban Ahmet , Tiris Mustafa 
Published: November 2007

AbstractThis paper evaluates the performance and suitability of membrane bioreactor (MBR) technology for grey and black water treatment. For this purpose, two MBRs were installed on a site located in the Training and Demonstration Center (TDC) of TUBITAK Marmara Research Center (MRC). The grey and black water originated from the lodging houses of the MRC. The study involves wastewater characterization, start‐up, operation of the MBRs and evaluation of the effluent quality according to the current water reuse standards. Two pilot scale MBRs with an effective volume of 600 L were operated for a period of 50 days with a hydraulic retention time (HRT) of 18 and 36 h, respectively for grey and black water. The average removal efficiencies were, 95% COD, 92% T‐N, and 99% TSS for grey water and 96% COD, 89% T‐N, and 99% TSS for black water. Total and faecal coliform were not detected in either permeates. The results showed that the effluent quality of grey and black water treated by the MBR complied with the national and international reuse criteria for different uses. However, some modifications are needed to optimize the removal efficiency especially for simultaneous organic matter and nutrient removal and further investigations into long term monitoring are necessary.
Kinetical Study of the Photoinduced Degradation of Imidacloprid in Aquatic Media
Authors: Redlich Dirk , Shahin Nabil , Ekici Perihan , Friess Albrecht , Parlar Harun 
Published: November 2007

AbstractThe photoinduced degradation of the insecticide imidacloprid in natural water samples was performed in order to describe its abiotic degradation. Numerous degradation products could be identified with the help of spectroscopic methods. The main photoproducts were 1‐[(6‐chloro‐3‐pyridinyl)methyl]‐N‐nitroso‐2‐imidazolidinimine, 1‐[(6‐chloro‐3‐pyridinyl)methyl]‐2‐imidazolidinimine (which is known to be more toxic for warm‐blooded animals than imidacloprid) and 1‐[(6‐chloro‐3‐pyridinyl)methyl]‐2‐imidazolidinone. Besides numerous other degradation products, 6‐chloro‐nicotine‐amide was identified as the end product of the photolytic reaction. The photoinduced reaction of imidacloprid followed pseudo first‐order reaction kinetics and resulted from a triplet‐controlled intermediate state with a triplet energy between 281–290 kJ/mol and an half‐life time of 4.6×10–9 s. With the help of measured quantum yields (ΦS), the half‐life time of imidacloprid in natural waters was estimated at 3 days. The calculated half‐life times of 1‐[(6‐chloro‐3‐pyridinyl)methyl]‐2‐imidazolidinimine was much shorter, 0.24 days, while those of 1‐[(6‐chloro‐3‐pyridinyl)methyl]‐2‐imidazolidinone and 6‐chloro‐nicotine‐amide were higher at 270 and 660 days, respectively.
Aleppo Pine Bark as a Biomonitor of Atmospheric Pollution in the Arid Environment of Jordan
Authors: Al‐Alawi Mu'taz M. , Batarseh Mufeed I. , Carreras Hebe , Alawi Mahmoud , Jiries Anwar , Charlesworth Susanne M. 
Published: November 2007

AbstractMonitoring of atmospheric pollution using Aleppo bark as a bioindicator was carried out in the industrial area surrounding the Al‐Hussein thermal power station and the oil refinery at Al‐Hashimyeh town, Jordan. The concentrations of heavy metals (copper, lead, cadmium, manganese, cobalt, nickel, zinc, iron, and chromium) were analyzed in bark samples collected from the study area during July 2004. The results showed that high levels of heavy metals were found in tree bark samples retrieved from all studied sites compared with the remote reference site. This is, essentially, due to the fact that the oil refinery and the thermal power plant still use low‐quality fuel oil from the by‐products of oil refining. Automobile emissions are another source of pollution since the study area is located along a major heavy‐traffic highway. It was found that the area around the study sites (Al‐Hashimyeh town, Zarqa) is polluted with high levels of heavy metals. Pine bark was found to be a suitable bioindicator of aerial fallout of heavy metals in arid regions.
Thinking in Structure‐Activity Relationships – A Way Forward Towards Sustainable Chemistry
Authors: Jastorff Bernd , Störmann Reinhold , Ranke Johannes 
Published: November 2007

AbstractThinking in structure‐activity relationships (T‐SAR) is presented as an approach to a systematic collection and networking of knowledge and hypotheses regarding chemical structures. T‐SAR can be accompanied by quantitative correlation studies commonly referred to as quantitative structure‐activity relationships (QSAR) or linear free energy relationships (LFER). Some important limitations of these quantitative approaches are illustrated using the examples of biopartitioning and equilibrium partitioning in general. A systematic scheme for the qualitative analysis of a structural formula in seventeen steps is shown, covering stereochemistry, molecular interaction potentials, and reactivity. As an example for the application of T‐SAR, contributions to the molecular design of ionic liquids are described.
Fate of the Benzimidazole Antiparasitics Flubendazole and Fenbendazole in Manure and Manured Soils
Authors: Kreuzig Robert , Blümlein Katharina , Höltge Sibylla 
Published: November 2007

AbstractThe fate of flubendazole and fenbendazole in manure and manured soils was investigated under laboratory and field conditions. In pig manure, both 14C‐labeled benzimidazoles disappeared slowly. After a 102 day incubation period, extractable fractions contained 72% flubendazole or 80% fenbendazole of the radioactivity initially applied. The latter was accompanied by 4% of the corresponding metabolite fenbendazole‐sulfoxide. Non‐extractable residues amounted to 24 and 13%, respectively. On this basis, test manures with 7 day aged benzimidazole residues were prepared. Mobility tendencies differed for clay and sand soils as well as for standard and test‐manure application. Regarding KOC > 1100 L/kg, however, criteria for potential leachers were not fulfilled. The metabolic fate of flubendazole was predominated by the occurrence of the parent compound while fenbendazole was accompanied by fenbendazole‐sulfoxide. In clay soil samples after standard application, DT50 values were 174 and 54 days, respectively. Mineralization and formation of non‐extractable residues were of minor relevance. For fenbendazole, these processes were intensified after test‐manure application. Due to enhanced formation of fenbendazole‐sulfoxide, fenbendazole‐sulfone, and non‐extractable residues, DT50 thus dropped to 9 days. Similar mobility and degradability tendencies were also found under field conditions. In the sand soil, however, the metabolic dynamics decelerated due to its lower microbial activity.
Ecologically Benign Lubricants – Evaluation From a Life Cycle Perspective
Authors: Herrmann Christoph , Hesselbach Jürgen , Bock Ralf , Zein André , Öhlschläger Gerlind , Dettmer Tina 
Published: November 2007

AbstractUsing mineral oil based coolants for the machining of metals causes environmental problems. Besides plant seed oil, animal fat and used cooking oil proved to be raw material sources for alternative ester based coolants which can be used as substitutes for mineral oil. In this paper their properties are compared from a life cycle perspective with those of mineral oil and plant seed oil ester products regarding technical, ecological and economical aspects. In this context grinding tests, Life Cycle Assessment and Life Cycle Costing were performed. The three disciplines are brought together in a material flow model and, therefore, results are well harmonized.
Targeting cytotoxic T‐lymphocyte antigen‐4 (CTLA‐4)
Authors: O'Day Steven J. , Hamid Omid , Urba Walter J. 
Published: November 2007

AbstractCancer immunotherapy centers on modulating the host's tumor‐directed immune response. One promising approach involves augmentation of cell‐mediated immunity by interrupting T‐cell pathways responsible for immune down‐regulation or tolerance. The discovery of cytotoxic T‐lymphocyte antigen‐4 (CTLA‐4) and its role as a key negative regulator for T cells has prompted efforts to target this signaling molecule to improve cancer therapy. Activation, or ‘priming’, of naive T cells in response to tumor‐cell invasion comprises a dual‐signaling mechanism. Signal 1 requires tumor‐associated antigen recognition by the T‐cell receptor, while signal 2 occurs through binding of CD80 or CD86 (B7.1 of 2) on the antigen presenting cell (APC) with CD28 on the T cell. Importantly, there is a final step responsible for naturally occurring immune regulation; this occurs in response to competitive binding of CD80/CD86 on the APC by CTLA‐4 on the T cell. This ‘immune checkpoint’ interrupts signal 2 and inhibits the activated T cell. Targeting CTLA‐4 as an anticancer strategy: Following proof‐of‐concept studies in animals, fully human anti‐CTLA‐4 antibodies were developed and 2 are undergoing clinical evaluation. Ipilimumab and tremelimumab have shown promising antitumor activity, initially in patients with advanced melanoma. Class‐specific immune‐related adverse events (irAEs) were common and mostly transient and/or manageable. These events are thought to be mechanism‐of‐action‐related, indicating immune tolerance is broken; this relation may also explain the association between irAEs and response seen in several trials. Interruption of immune inhibitory pathways via CTLA‐4 blockade appears to be a promising strategy for cancer immunotherapy. Cancer 2007. © 2007 American Cancer Society.
Two‐Photon Absorption Properties of Dehydrobenzo[12]annulenes and Hexakis(phenylethynyl)benzenes: Effect of Edge‐Linkage
Authors: Kamada Kenji , Antonov Liudmil , Yamada Satoru , Ohta Koji , Yoshimura Takashi , Tahara Kazukuni , Inaba Akiko , Sonoda Motohiro , Tobe Yoshito 
Published: November 2007

AbstractTwo‐photon absorption (TPA) properties of two trefoil‐shaped compounds with different edge linkages—tris(hexadehydrotribenzo[12]annulene) and tris(tetradehydrotribenzo[12]annulene)—and three asterisk‐shaped compounds having no edge‐linkage—hexakis(phenylethynyl)benzenes—are investigated experimentally by the open‐aperture Z‐scan and TPA‐induced fluorescence methods with wavelength tuneable femtosecond pulses. The compound with ethynylene edge‐linkage exhibits the most intense TPA (the maximal TPA cross section is 1300±170 GM at 572 nm where 1 GM=10−50 cm4 s molecule−1 photon−1). The TPA activity of the compounds is primarily explained in terms of the planarity of the molecules in relation with the type of edge‐linkage.