bluuebunny/crossref_metadata_2025 huggingface dataset:
Atypical Human Responses to Low‐Level Environmental Contaminants: The Problem of Multiple Chemical Sensitivities
Authors: Cullen Mark R.
Published: February 2011

The practice of occupational medicine has been summarized in the present study. There has been a rapid increase in concern about the impacts of many hazards, which arise in the non‐industrial setting, impacting far larger numbers of workers who often bring very different experiences and expectations regarding health in the workplace. Threshhold limit values (TLV's) or occupational exposure limits, onto the possibility of effects occurring at lower levels have been studied. The classic model human dose‐response curve for a direct acting cytotoxic chemical such as an irritant, solvent or pesticide has been presented. All theories from toxicologic research and reports suggest that for each hazard there exists some “threshold”. These thresholds in practice have been derived from various epidemiological studies, animal experiments, etc. The multiple chemical sensitivities (MCS) and its theories of pathogenesis have also been addressed.
Analytical Methods
Authors: Lieckfield Robert G.
Published: February 2011

The accurate determination of workplace exposures begins with the selection of an appropriate sampling device and continues through the analysis of the collected samples in the industrial hygiene laboratory. This chapter focuses on laboratory methodologies for the analysis of industrial hygiene samples. The complexity of this field is compounded by the need to identify and quantify trace quantities of organic and inorganic substances in the presence of numerous potential interferences. Various industrial hygiene analyses have been summarized. The technology of laboratory instrumentation has also become advanced and many microprocessors‐based sophisticated instruments have been incorporated in the industrial hygiene laboratory community.
Odors: Measurement and Control
Authors: Turk Amos , Merlo Angela , Cha Samuel
Published: February 2011

Odor intensity is the magnitude of the olfactory sensation produced on exposure to an odorant. The reduction of odor intensity is accomplished by removal of odorant from the atmosphere, the process is equivalent to gas and vapor abatement, or to air cleaning, but with some special considerations. When an odorous atmosphere is improved by the addition of another (usually pleasant) odorant under conditions in which chemical reactions are not involved, the process is known as odor modification. Various methos of odor measurement have been discussed. The present study also focuses odor perception, olfactory adaptation and the various methods for odor control.
Industrial Noise and Hearing Conservation
Authors: Byrne David C. , Michael Kevin L. , Tufts Jennifer B.
Published: February 2011

The rise of industrial noise and its effect of occupational hearing loss are now considered as common problems across nearly all industries, which have a significant impact on safety and work performance. Occupational hearing loss is nearly always preventable and its prevention benefits the employer as well as the individual employees.
Heat Stress
Authors: Larrañaga Michael D. , Bernard Thomas E.
Published: February 2011

Heat stress is known as the aggregate of external heat from the environment, internal heat generated by the human body through physical activity and metabolism, and the insulating effects of the clothing worn, which collectively impose a thermal load on a person. Heat strain is the human response to heat stress. This chapter presents an in depth review of the development and current status of heat stress standards and guidelines; the physiology of human thermal exchange with the environment; the measurement and interpretation of the thermal environment; and the assessment of heat stress and heat strain; and the application of controls for the prevention of heat stress and heat strain.
Physiological Effects of Altered Barometric Pressure
Authors: Piantadosi Claude A.
Published: February 2011

High and low pressure environments have continued to play important roles in our technological society for many reasons. The earliest engineering applications of high pressure, to maintain dry working conditions in caissons and tunnels, are still in use today, and still extract a toll in decompression sickness and aseptic bone necrosis from workers who undergo daily decompression after long shifts under compressed air. As exploitation of undersea resources has expanded, especially sub‐sea oil, so has the need for greater working depth and time, hence increasing the vulnerability of the diver to injury. The present chapter addresses the physiology of gas exchange in the lungs and tissues, acute and chronic health effects of diving, fitness to dive and relevant therapies.
Biohazards and Occupational Disease
Authors: Heinsohn Patricia A.
Published: February 2011

Microbes live in our environment and adapted to survive under extreme harsh conditions. Most microorganisms do not cause disease in humans or animals and some have beneficial uses. The present study primarily deals with microorganisms that can cause occupational disease and also deals with several emerging infectious diseases. Besides this many occupational diseases and their etiologic biohazards have been presented, accompanied by pertinent information pertaining to the disease, exposure, and annotated control methods. Further it has also been suggested that the industrial hygiene principles of anticipation, recognition, evaluation, and control of occupational hazards are as applicable to biohazards as to other occupational hazards.
Respiratory Protective Equipment
Authors: Birkner Jeffrey S. , Colton Craig E.
Published: February 2011

The respirators have been used for almost 2000 years and the genesis of their technical development is actually the mid‐19th century. The Bureau of Mines in 1919 initiated the first respirator certification program in the United States and certified their first respirator. In 1995, NIOSH proclaimed new certification regulations. The study finds that the respiratory protective equipment (RPE) should be used only when all higher priority control steps are not technically or financially feasible. Thus, RPE continues to be an important component in many respiratory exposure control plans. The present study also addresses the performance of RPE and its evaluation in the laboratory and in the workplace. The respirator program ensures that the RPE selected is able to provide adequate protection under the conditions of intended use.
Occupational Health and Safety Management Systems
Authors: Redinger Charles , Dotson Kyle , Leibowitz Alan
Published: February 2011

Occupational health and safety management systems (OHSMS) are a powerful risk management tool. They provide IH and EHS professionals with a robust and structured management approach. OHS management systems have significant roots in the quality management systems developed in United Sates in the early 20
th
century. ISO and other NGO standards have been developed with an eye toward the value of conformity assessment to ensure a common application of specific objectives identified in applicable standards. The pyramid model has been used as a powerful tool to help OHS professionals and their organizations to develop and implement OHS management systems. Besides this, numerous implementation steps for OHS management systems have been discussed.
Agricultural Hygiene
Authors: Popendorf William , Donham Kelley J.
Published: February 2011

The present chapter describes the dilemma of agriculture as both an industry and as a way of life. Despite some increased interest within agriculture to establish safety and health programs due to farms becoming larger and more farms having fallen under the OSHA requirements, agriculture remains one of the most hazardous occupational environments in America. Hazards reviewed within this chapter have been organized into acute and cumulative trauma, respiratory hazards, pesticides, veterinary chemicals, zoonoses, dermatoses, physical hazards, cancer, and psychosocial stresses that are either characteristic of or unique to agriculture. Emphasis has been given to explain how the traditional industrial hygiene components of anticipation, recognition, evaluation, and control can be applied to agriculture. The chapter concludes with a discussion of various models of administrative and sociological programs designed to improve health and safety conditions on all farms.
Characterization of Hydrogen Storage Materials and Systems with Photons and Neutrons
Authors: Pranzas P. Klaus , Bösenberg Ulrike , Karimi Fahim , Münning Martin , Metz Oliver , Minella Christian Bonatto , Schmitz Heinz‐Werner , Beckmann Felix , Vainio Ulla , Zajac Dariusz , Welter Edmund , Jensen Torben R. , Cerenius Yngve , Bormann Rüdiger , Klassen Thomas , Dornheim Martin , Schreyer Andreas
Published: February 2011

Complex hydrides are very promising candidates for future light‐weight solid state hydrogen storage materials. The present work illustrates detailed characterization of such novel hydride materials on different size scales by the use of synchrotron radiation and neutrons. The comprehensive analysis of such data leads to a deep understanding of the ongoing processes and mechanisms. The reaction pathways during hydrogen desorption and absorption are identified by in situ X‐ray diffraction (XRD). Function and size of additive phases are estimated using X‐ray absorption spectroscopy (XAS) and anomalous small‐angle X‐ray scattering (ASAXS). The structure of the metal hydride matrix is characterized using (ultra) small‐angle neutron scattering (SANS/USANS). The hydrogen distribution in tanks filled with metal hydride material is studied with neutron computerized tomography (NCT). The results obtained by the different analysis methods are summarized in a final structural model. The complementary information obtained by these different methods is essential for the understanding of the various sorption processes in light metal hydrides and hydrogen storage tanks.
Thermal Cycling Stresses in W‐Monofilament Reinforced Copper
Authors: Schöbel Michael , Jonke Johannes , Degischer H. Peter , Herrmann Aurelia , Brendel Annegret , Wimpory Robert , Buslaps Thomas
Published: February 2011

New materials have to be developed for fusion reactor systems to withstand the high thermal load and heavy irradiation under service conditions. The divertor element collects the residuals of the nuclear reaction and withdraws heat from the reaction chamber into a heat sink. A thermal flux of ≈20 W mK−1 can be expected in such components. A plasma facing W plate is attached to a CuCrZr heat sink suffering CTE mismatch stresses at the interface due to pulsed operation required for the Tokamak reactor design. Fiber reinforced metal matrix composites are applied as an interlayer to reduce macroscopic interfacial stresses in these components. W‐wire reinforced copper is a promising material for this application due to a good fiber‐matrix bonding strength which is further increased by surface etching or graded interface designs. Thermal stresses in between the matrix and the wires are responsible for thermal fatigue damage within the constituents and at their interface. Neutron and synchrotron diffraction was performed in situ during thermal cycling to determine the micro stress amplitudes and their changes under simulated service conditions.
Simultaneous Modification of Bottom‐Contact Electrode and Dielectric Surfaces for Organic Thin‐Film Transistors Through Single‐Component Spin‐Cast Monolayers
Authors: Acton Orb , Dubey Manish , Weidner Tobias , O’Malley Kevin M. , Kim Tae‐Wook , Ting Guy G. , Hutchins Daniel , Baio J. E. , Lovejoy Tracy C. , Gage Alexander H. , Castner David G. , Ma Hong , Jen Alex K.‐Y.
Published: February 2011

An efficient process is developed by spin‐coating a single‐component, self‐assembled monolayer (SAM) to simultaneously modify the bottom‐contact electrode and dielectric surfaces of organic thin‐film transistors (OTFTs). This effi cient interface modifi cation is achieved using n‐alkyl phosphonic acid based SAMs to prime silver bottom‐contacts and hafnium oxide (HfO2) dielectrics in low‐voltage OTFTs. Surface characterization using near edge X‐ray absorption fi ne structure (NEXAFS) spectroscopy, X‐ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR‐FTIR) spectroscopy, atomic force microscopy (AFM), and spectroscopic ellipsometry suggest this process yields structurally well‐defi ned phosphonate SAMs on both metal and oxide surfaces. Rational selection of the alkyl length of the SAM leads to greatly enhanced performance for both n‐channel (C60) and p‐channel (pentacene) based OTFTs. Specifi cally, SAMs of n‐octylphos‐phonic acid (OPA) provide both low‐contact resistance at the bottom‐contact electrodes and excellent interfacial properties for compact semiconductor grain growth with high carrier mobilities. OTFTs based on OPA modifi ed silver electrode/HfO2 dielectric bottom‐contact structures can be operated using < 3V with low contact resistance (down to 700 Ohm‐cm), low subthreshold swing (as low as 75 mV dec−1), high on/off current ratios of 107, and charge carrier mobilities as high as 4.6 and 0.8 cm2 V−1 s−1, for C60 and pentacene, respectively. These results demonstrate that this is a simple and efficient process for improving the performance of bottom‐contact OTFTs.
Enhanced Nucleation of Vortices in Soft Magnetic Materials Prepared by Silica Nanosphere Lithography
Authors: Martin Norbert , Bigall Nadja‐Carola , Mönch Ingolf , Gemming Thomas , Eychmüller Alexander , Mattheis Roland , Schäfer Rudolf , Schultz Ludwig , McCord Jeffrey
Published: February 2011

Magnetic vortices show promise as data storage structures, however the vortex formation process imposes a lower limit on the element’s size. In this article a technique is presented, which application increases the probability of nucleating of magnetic vortices in sub‐micrometer sized soft magnetic thin film elements. By tailoring the edge geometry of the elements, the symmetry of their magnetic configuration is broken in a manner which favors vortex nucleation. Micromagnetic simulations are presented, which demonstrate this effect in soft‐magnetic disks with beveled edges. The favored edge geometry is realized by applying nanosphere lithography directly on top of a ferromagnetic thin film material. In this process, the film is masked with a self assembled monolayer of SiO2‐nanospheres and subsequently ion‐etched. The resulting magnetic reversal loops show that in both magnetically isolated as well as in closely packed arrays of beveled disks, vortex formation takes place. The technique presented facilitates the vortex formation even in closely packed and small elements. The lowering of the minimum critical diameter for vortex formation enables a significant increase of data storage density in devices based on magnetic vortices.
Wavelength‐Selective Light‐Induced Release from Plasmon Resonant Liposomes
Authors: Leung Sarah J. , Kachur Xenia M. , Bobnick Michael C. , Romanowski Marek
Published: February 2011

Biodegradable, spectrally tunable plasmon resonant nanocapsules are created via the deposition of gold onto the surface of 100 nm diameter thermosensitive liposomes. These nanocapsules exhibit selective release of encapsulated contents upon illumination with light of a wavelength matching their distinct resonance bands. In this study, 760 and 1210 nm laser illumination elicits complete release from gold‐coated liposomes with a corresponding resonance, while causing minimal release from liposomes with an unmatching resonance. Spectrally selective release is accomplished through the use of multiple, low‐intensity laser pulses delivered over a period of minutes, ensuring that illumination affects the gold‐coated liposomes without heating the surrounding media. The use of pulsed illumination to achieve spectral selectivity is validated experimentally and through modeling of the heat equation. The result of this illumination scheme for selective release using multiple wavelengths of light is a biologically safe mechanism for realizing drug delivery, microfluidic, and sensor applications.
Die Taube – eine Erfolgsgeschichte. Vom Liebling der Götter zur Eroberung der Städte
Authors: Haag‐Wackernagel Daniel
Published: February 2011

Kaum ein anderes Tier hat sich so erfolgreich in der Welt des Menschen etabliert wie die Taube. Sie verfügt über Eigenschaften in Physiologie und Verhalten, die sie optimal für eine “Karriere” als Haustier und als vielfältiges Sinnbild für unterschiedliche göttliche Wesen und Tugenden prädisponieren. Diese Assoziationen mit der Taube bilden eine wichtige Grundlage für deren Akzeptanz und Wertschätzung in der Bevölkerung. Straßentauben sind die frei lebenden Nachfahren von Feld‐ und Haustauben. Die Populationsgröße der Tauben wird weitgehend durch den Umfang des Nahrungsangebotes bestimmt. Das Taubenproblem in unseren Städten kann nur durch eine Senkung der Nahrungsgrundlage gelöst werden, da es nicht möglich ist, Taubenpopulationen durch Erhöhung der Mortalität oder Senkung der Natalität nachhaltig zu reduzieren.
Der Riesengleitflieger: verkehrte Landung im Stammbaum der Primaten
Authors: Schmitz Jürgen
Published: February 2011

Der Riesengleitflieger, vertreten durch die beiden rezenten Arten Cynocephalus volans (Philippinischer Colugo) und Galeopterus variegatus (Malaysischer Colugo), ist der einzige Vertreter der Dermoptera (übersetzt “Hautflügler”) und wird auch als Pelzflatterer oder Colugo bezeichnet. Einer ersten mitochondrialen Genomanalyse zufolge wurde er als Schwestergruppe der höheren Primaten angesehen – ein Irrtum, wie sich bald herausstellte.
Porträt: Doktorandenprogramm des European Molecular Biology Laboratory (EMBL)
Authors: Matuschek Elke
Published: February 2011

Das “International PhD Programme” des European Molecular Biology Laboratory (EMBL), das 1983 gegründet wurde, ist bekannt für die intensive Betreuung seiner Schützlinge. Das Programm, an dem sich 20 europäische Staaten und Australien als assoziierter Mitgliedsstaat beteiligen, ist an fünf europäischen Standorten aktiv, um Hochschulabsolventen zu Nachwuchswissenschaftlern auszubilden. Unsere Autorin Elke Matuschek sprach mit Helke Hillebrand, Leiterin des EMBL International PhD Programmes am EMBL in Heidelberg.
Hydrolysis of Cellulose over CsxH3–xPW12O40 (X = 1–3) Heteropoly Acid Catalysts
Authors: Tian J. , Fang C. , Cheng M. , Wang X.
Published: February 2011

A series of insoluble heteropolytungstate salts, CsxH3–xPW12O40 (x = 1–3), were prepared and applied to the selective hydrolysis of microcrystalline cellulose to sugars in the aqueous phase. CsxH3–xPW12O40 were active toward the hydrolysis of cellulose into total reducing sugars (TRS) and glucose, which are the important products for the application for biofuels. The conversion of cellulose and total yield for the main products increased with increasing acidity of the catalyst. Cs1H2PW12O40 exhibited the best catalytic activity in terms of the conversion of cellulose and yields for TRS and glucose, while Cs2.2H0.8PW12O40 showed the highest selectivity for TRS and glucose.
Structural and Electronic Characteristics of a Novel BEDT‐TTF Derivative: [BEDT‐TTF]2[Cu2Br3]
Authors: Schödel Frauke , Tutsch Ulrich , Isselbächer Friedhelm , Schweitzer Dieter , Sänger Inge , Bolte Michael , Bats Jan W. , Müller Jens , Lang Michael , Wagner Matthias , Lerner Hans‐Wolfram
Published: February 2011

Crystals of κ‐[(BEDT‐TTF)2][Cu(N(CN)2)Br] were available with good quality and high reproducibility from the BEDT‐TTF electro‐oxidation with an electrolyte molar ratio [Ph4P][N(CN)2]:CuBr of 1:1 in a mixture of THF and ethylene glycol. Surprisingly, by varying the electrolyte molar ratio from 1:1 to 1:8 a novel type of BEDT‐TTF salt, [BEDT‐TTF]2[Cu2Br3], was formed. The solid‐state structure of [BEDT‐TTF]2[Cu2Br3] consists of stacks of non‐coordinated BEDT‐TTF molecules and stacks of the contact ions [BEDT‐TTF][Cu2Br3] (triclinic space group, P1). The two crystallographically independent [BEDT‐TTF][Cu2Br3] contact ions in the second stack are related by a pseudo‐inversion center. Resistivity measurements on single crystals reveal that [BEDT‐TTF]2[Cu2Br3] possesses a semiconductor‐like behavior under normal pressure from room temperature down to at least 10 K.
Novel Green Light Emitting Nondiscoid Liquid Crystalline Zinc(II) Schiff‐Base Complexes
Authors: Bhattacharjee Chira R. , Das Gobinda , Mondal Paritosh , Prasad Subbarao Krishna , Rao D. S. Shankar
Published: February 2011

A new series of nondisc‐like ZnII Schiff base complexes of the type [Zn (4‐CnH2n+1O)2 salophen], n = 14, 16, 18, salophen = N,N′‐phenylenebis(salicylideneiminato), have been prepared and their mesogenic, photophysical properties investigated. The mesomorphic behaviour of these compounds was studied by differential scanning calorimetry, polarized optical microscopy and X‐ray diffraction (XRD) techniques. The ligands are found to be nonmesogenic, but their complexes exhibited a columnar mesomorphism. The XRD‐study revealed that the molecules are self‐organized into columnar mesophase of the primitive rectangular (Colr) and/or monoclinic oblique type. At room temperature with 360 nm excitation, all the complexes showed green emission in dichloromethane solution (ca. 507 nm, Φ = 22 %) as well as in the solid state (ca. 516 nm, Φ = 9 %). The DFT calculations were performed using the DMol3 program at BLYP/DNP level to obtain the stable electronic structure of the complex.
Metathesis Reactions of Carbohydrates: Recent Highlights in Alkyne Metathesis
Authors: López J. Cristóbal , Plumet Joaquín
Published: February 2011

Metathesis processes play a prominent role in the development of useful synthetic transformations because of their mildness and tolerance of functional groups. On the other hand, carbohydrates have gained well‐deserved importance in the study of biological processes. This review summarizes a decade of research in the application of alkyne metathesis (AM) reactions in some of its variants to carbohydrates and carbohydrate‐related compounds.
Fourfold Suzuki–Miyaura and Sonogashira Cross‐Coupling Reactions on Tetrahedral Methane and Adamantane Derivatives
Authors: Schilling Christine I. , Plietzsch Oliver , Nieger Martin , Muller Thierry , Bräse Stefan
Published: February 2011

An efficient way to generate a series of rigid tetrahedral organic building units from common methane and adamantane precursors is presented. Suzuki–Miyaura and Sonogashira cross‐coupling reactions are used to effectively generate these shape‐persistent molecular tectons. Especially theSonogashira reactions employing the readily available tetrahedral alkynes and commercial iodides and bromides are very effective.
I2‐Induced Stereospecific Synthesis of 4‐Piperidones through Double Mannich Reaction and Tandem Cyclization
Authors: Jia Xiao‐Dong , Chen Xiang‐Ning , Wang Xiao‐E , Huo Cong‐De , Wang Wen‐Juan , Ren Yan , Wang Xi‐Cun
Published: February 2011

An I2‐induced double Mannich reaction and tandem cyclization of imines and ketones was investigated for the synthesis of a series of 1,2,6‐triaryl‐4‐piperidones. During the process of cyclization, only one product was produced out of four possible 4‐piperidones. Two pathways involving the balance between chelation effects and hydrogen bonding were proposed to rationalize the formation of the products, which was supported by further investigation of the reaction between β‐aminoketones and imines.
Demographic differences in Down syndrome livebirths in the US from 1989 to 2006
Authors: Egan James F. X. , Smith Kathleen , Timms Diane , Bolnick Jay M. , Campbell Winston A. , Benn Peter A.
Published: February 2011

Objective

To explore demographic differences in Down syndrome livebirths in the United States.

Methods

Using National Center for Health Statistics (NCHS) birth certificate data from 1989 to 2006 we analyzed Down syndrome livebirths after correcting for under‐reporting. We created six subsets based on maternal age (15–34 and 35–49 years old); US regions, that is, Northeast, Midwest, South and West; marital status, (married, unmarried); education, ( ≤ 12 years, ≥ 13 years); race, (white, black); and Hispanic ethnicity, (non‐Hispanic, Hispanic). We estimated expected Down syndrome livebirths assuming no change in birth certificate reporting. The percentage of expected Down syndrome livebirths actually born was calculated by year.

Results

There were 72 613 424 livebirths from 1989 to 2006. There were 122 519 Down syndrome livebirths expected and 65 492 were actually born. The Midwest had the most expected Down syndrome livebirths actually born (67.6%); the West was lowest (44.4%). More expected Down syndrome livebirths were born to women who were 15 to 34 years old (61 vs 43.8%) and to those with ≤ 12 years education (60.4 vs 46.9%), white race (56.6 vs 37%), unmarried (56.0 vs 52.5%), and of Hispanic ethnicity (55.0 vs 53.3%).

Conclusion

The percentage of expected Down syndrome livebirths actually born varies by demographics. Copyright © 2011 John Wiley & Sons, Ltd.
DWSB for heterotic flux compactifications
Authors: Held J.
Published: February 2011

We investigate the construction of non‐supersymmetric vacua in compactifications of heterotic string theory with intrinsic torsion and background fluxes. We do this by using the technique of domain‐wall supersymmetry breaking (DWSB) that was developed in the context of type II compactifications. By means of a scalar potential we derive conditions on the compactification manifold that must hold in order to satisfy the equations of motion up to order α′.
Symplectic gaugings and the field‐antifield formalism
Authors: Coomans F. , De Rydt J. , Van Proeyen A.
Published: February 2011

We give an example of how conventional gauging methods obstruct a systematic analysis of gauged supergravities. We discuss how the embedding tensor formalism deals with these problems and argue that the gauge algebra related to the embedding tensor formalism is soft, open and reducible. We connect the embedding tensor formalism to the field‐antifield (or Batalin‐Vilkovisky) formalism, which is the most general formulation known for gauge theories.
Using an autonomous robot to maintain privacy in assistive environments
Authors: Armbrust Christopher , Mehdi Syed Atif , Reichardt Max , Koch Jan , Berns Karsten
Published: February 2011

In our societies, the number of senior citizens living on their own is increasing steadily. The lack of permanent attention results in the late detection of emergency situations. Labour‐intensive care is already a high burden for the society; therefore, it seems reasonable to promote technology that helps to detect and react in case of emergency situations that elderly people may encounter.

In the last decade, assistive environments have been established by integrating surveillance devices into the living environments giving remote operators access to monitor the senior inhabitant at home for detecting emergency situations. However, due to poor privacy in terms of intrusion into the private life of an elderly person, there will be an unfavourably low acceptance of such systems.

This paper introduces a two‐stage strategy and proposes to replace a possibly large number of human‐controlled monitoring devices by a single autonomous mobile system. The first stage will be performed by the autonomous system to detect an emergency situation. The human operator will be obligatory only at the final stage when the system assumes that an emergency has occurred and the final evaluation of the situation is required. The self‐assessment will reduce the human factor related to privacy issues. Copyright © 2011 John Wiley & Sons, Ltd.
SCN‐SI‐021 achieving privacy and access control in pervasive computing environments
Authors: Magkos Emmanouil , Kotzanikolaou Panayiotis
Published: February 2011

This paper focuses on the inherent trade‐off between privacy and access control in pervasive computing environments (PCEs). On one hand, service providers require user authentication and authorization for the provision of a service, while at the same time end users require untraceability and unlinkability for their transactions. There are also cases where the anonymity of a specific credential must be revoked and a real identity be traced, in order to establish accountability. We analyze privacy and security requirements for PCEs and we show that existing privacy‐preserving access control schemes do not fully satisfy these requirements. Then we propose two approaches towards privacy‐preserving access control in PCEs. Our goal is twofold: (a) to enhance privacy by achieving untraceability and unlinkability even against malicious insiders and (b) to enhance security by achieving conditional traceability of user credentials, and if possible, non‐repudiation of evidence concerning the user's participating in a transaction. Finally, we analyze and compare the proposed schemes against existing schemes. Copyright © 2011 John Wiley & Sons, Ltd.
Engineering, Characterization and Directional Self‐Assembly of Anisotropically Modified Nanocolloids
Authors: Bhaskar Srijanani , Gibson Christopher T. , Yoshida Mutsumi , Nandivada Himabindu , Deng Xiaopei , Voelcker Nicolas H. , Lahann Joerg
Published: February 2011

Along with traditional attributes such as the size, shape, and chemical structure of polymeric micro‐objects, control over material distribution, or selective compartmentalization, appears to be increasingly important for maximizing the functionality and efficacy of biomaterials. The fabrication of tri‐ and tetracompartmental colloids made from biodegradable poly(lactide‐co‐glycolide) polymers via electrohydrodynamic co‐jetting is demonstrated. The presence of three compartments is confirmed via flow cytometry. Additional chemical functionality is introduced via the incorporation of acetylene‐functionalized polymers into individual compartments of the particles. Direct visualization of the spatioselective distribution of acetylene groups is demonstrated by confocal Raman microscopy as well as by reaction of the acetylene groups with azide‐biotin via ‘click chemistry’. Biotin–streptavidin binding is then utilized for the controlled assembly and orientation of bicompartmental particles onto functionalized, micropatterned substrates prepared via chemical vapor deposition polymerization.
Affibody‐Functionalized Gold–Silica Nanoparticles for Raman Molecular Imaging of the Epidermal Growth Factor Receptor
Authors: Jokerst Jesse V. , Miao Zheng , Zavaleta Cristina , Cheng Zhen , Gambhir Sanjiv S.
Published: February 2011

The affibody functionalization of fluorescent surface‐enhanced Raman scattering gold–silica nanoparticles as multimodal contrast agents for molecular imaging specific to epidermal growth factor receptor (EGFR) is reported. This nanoparticle bioconjugate reports EGFR‐positive A431 tumors with a signal nearly 35‐fold higher than EGFR‐negative MDA‐435S tumors. The low‐level EGFR expression in adjacent healthy tissue is 7‐fold lower than in the positive tumors. Validation via competitive inhibition reduces the signal by a factor of six, and independent measurement of EGFR via flow cytometry correlates at R2 = 0.92.
A healthy economy can break your heart
Authors: Ruhm Christopher J.
Published: February 2011

Panel data methods are used to investigate how deaths from coronary heart disease (CHD) in the United States vary with macroeconomic conditions. A one-percentage-point reduction in unemployment is predicted to raise CHD mortality by 0.75%, corresponding to almost 3,900 additional fatalities. The increase in relative risk is similar across age groups, implying that senior citizens account for most of the extra deaths. Direct evidence is obtained of a role for decreases in medical interventions treating coronary problems. CHD mortality increases rapidly when the economy strengthens but returns to or near its baseline level within five years for most groups.
Pyridoxal 5'‐phosphate in cerebrospinal fluid; factors affecting concentration
Authors: Footitt Emma J. , Heales Simon J. , Mills Philippa B. , Allen George F. G. , Oppenheim Marcus , Clayton Peter T.
Published: February 2011

Analysis of pyridoxal 5′‐phosphate (PLP) concentration in 256 cerebrospinal fluid (CSF) samples from patients with neurological symptoms showed that the variance is greater than indicated by previous studies. The age‐related lower reference limit has been revised to detect inborn errors of metabolism that lead to PLP depletion without a high false positive rate: <30 days, 26 nmol/L; 30 days to 12 months, 14 nmol/L; 1‐2 years, 11 nmol/L; >3 years, 10 nmol/L. Inborn errors leading to PLP concentrations below these values include pyridoxine‐dependent epilepsy due to antiquitin deficiency, and molybdenum cofactor deficiency that leads to the accumulation of sulfite, a nucleophile capable of reacting with PLP. Low PLP levels were also seen in a group of children with transiently elevated urinary excretion of sulfite and/or sulfocysteine, suggesting that there may be other situations in which sulfite accumulates and inactivates PLP. There was no evidence that seizures or the anticonvulsant drugs prescribed for patients in this study led to significant lowering of CSF PLP. A small proportion of patients receiving L‐dopa therapy were found to have a CSF PLP concentration below the appropriate reference range. This may have implications for monitoring and treatment. A positive correlation was seen between the CSF PLP and 5‐methyl‐tetrahydrofolate (5‐MTHF) and tetrahydrobiopterin (BH4) concentrations. All are susceptible to attack by nucleophiles and oxygen‐derived free‐radicals, and CSF has relatively low concentrations of other molecules that can react with these compounds. Further studies of CSF PLP levels in a wide range of neurological diseases might lead to improved understanding of pathogenesis and possibilities for treatment.
A simplified method for conducting ecological studies of land snail communities in urban landscapes
Authors: Clergeau Philippe , Tapko Noélie , Fontaine Benoit
Published: February 2011

Although land snail communities could be a good indicator of soil quality and landscape structure impact, they are seldom analysed in an urban context, probably because of the lack of interest in this ecosystem and because no fast and reliable method of inter‐site comparison seems to exist. The classical method of removing large quantities of soil leads to degradations unsuitable in urban gardens and involves time‐consuming sorting. For the purpose of ecological comparisons, we analysed different methods to assess land snail communities in urban parks in order to set up a simplified strategy. Snail communities were sampled in three parks within the city of Paris (France) using (1) quadrat method (litter and soil removed over a given area, snails sorted later in the laboratory), (2) visual search in situ (hand‐picking snails in the leaf litter), (3) wooden boards placed on the ground and regularly checked, and (4) pitfall traps, usually used for insect sampling. Our results suggest that the wooden board and pitfall trap did not yield enough data to determine community structure and that visual search was not sufficient to sample all dominant species, especially the smallest ones. In order to allow for replication of samples, we suggest a mixed strategy suitable for ecological comparisons, combining visual searches of five 0.5 m2areas (15 min for each area) and litter and soil sampling on two 0.0625 m2quadrats.
Diversity and metabolic impact of intestinalLactobacillusspecies in healthy adults and the elderly
Authors: Štšepetova Jelena , Sepp Epp , Kolk Helgi , Lõivukene Krista , Songisepp Epp , Mikelsaar Marika
Published: February 2011

The present study aimed at assessing the counts and species distribution of intestinal lactobacilli and exploring if the data are associated with BMI and blood glucose level in healthy adults and elderly persons. The BMI (P < 0·01), the level of fasting blood glucose (P < 0·001) and the total counts of lactobacilli (P < 0·01 by bacteriology;P < 0·001 by real-time PCR) were higher in the elderly. The number of species in adults was lower (P < 0·05), who were more often colonised withLactobacillus acidophilus(P = 0·031) andL. helveticus(P < 0·001). In contrast,L. plantarum(P = 0·035),L. paracasei(P < 0·001) andL. reuteri(P = 0·031) were more prevalent in the elderly.L. rhamnosuswas detected in adults (P < 0·001), but not in any elderly person. BMI was associated with counts of lactobacilli, adjusted for age and sex (P = 0·008). The higher BMI in both groups of persons was associated with the presence of obligate homofermentative lactobacilli andL. sakei, both adjusted for age and sex. Plasma glucose values were positively correlated with BMI and negatively correlated with colonisation withL. paracasei(P = 0·0238) in adults and on the borderline withL. fermentum(P = 0·052) in the elderly. Thus, the species-specific PCR analysis ofLactobacillussp. combined with viable plating data indicates substantial age-related structural differences in the intestinal lactobacilli communities. The higher counts of intestinalLactobacillussp. are associated with higher BMI and blood glucose content, while their specific fermentative groups and species of lactobacilli appear at different glucose levels both in adults and in the elderly.
A whey-based glutathione-enhancing diet decreases allergen-induced airway contraction in a guinea-pig model of asthma
Authors: Kloek J. , Mortaz E. , Van Ark I. , Bloksma N. , Garssen J. , Nijkamp F. P. , Folkerts G.
Published: February 2011

Since an allergen-induced early asthmatic reaction is likely to be accompanied by oxidative stress and since levels of the endogenous antioxidant glutathione can be enhanced by a whey-based diet (undenatured whey protein concentrate, UWPC), it was investigated whether UWPC could alleviate allergen-induced lung contractions. Guinea pigs were fed water or UWPC twice a day starting at day − 3 up to day 20. The animals were sensitised to ovalbumin or received saline on day 0. Serum samples were taken at several days after sensitisation to measure allergen-specific IgG. On day 20, lungs were isolated and perfused with buffer containing the allergen ovalbumin. Airway contractions were assessed, and mediators and indicators for oxidative stress were measured in the lung effluent. Moreover, glutathione levels were determined in the liver. The indicator of oxidative stress and airway contractile mediator, 8-iso-PGF2α, was increased upon ovalbumin challenge in ovalbumin-sensitised groups. Furthermore, thiobarbituric acid-reactive substances (TBARS) were increased as well. Sensitisation with ovalbumin increased IgG levels from day 12 up to day 20, which were not influenced by the UWPC diet. In contrast, the UWPC diet significantly enhanced glutathione levels in the liver. Moreover, the UWPC diet significantly reduced the ovalbumin-induced anaphylactic response by 45 % and decreased PGE2 levels by 55 % in the effluent fluid. We show for the first time that during anaphylaxis, there is acute oxidative stress in the respiratory tract. The UWPC diet did not influence the sensitisation response to the allergen but did increase endogenous glutathione levels. The UWPC diet profoundly reduces allergen-induced airway constrictions, which opens new avenues for dietary management of allergic diseases.
Iron absorption in hepcidin1 knockout mice
Authors: Masaratana Patarabutr , Laftah Abas H. , Latunde-Dada Gladys O. , Vaulont Sophie , Simpson Robert J. , McKie Andrew T.
Published: February 2011

Hepcidin, the Fe-regulatory peptide, has been shown to inhibit Fe absorption and reticuloendothelial Fe recycling. The present study was conducted to explore the mechanism of in vivo Fe regulation through genetic disruption of hepcidin1 and acute effects of hepcidin treatment in hepcidin1 knockout (Hepc1− / − ) and heterozygous mice. Hepcidin1 disruption resulted in significantly increased intestinal Fe uptake. Hepcidin injection inhibited Fe absorption in both genotypes, but the effects were more evident in the knockout mice. Hepcidin administration was also associated with decreased membrane localisation of ferroportin in the duodenum, liver and, most significantly, in the spleen of Hepc1− / −  mice. Hypoferraemia was induced in heterozygous mice by hepcidin treatment, but not in Hepc1− / −  mice, 4 h after injection. Interestingly, Fe absorption and serum Fe levels in Hepc1− / −  and heterozygous mice fed a low-Fe diet were not affected by hepcidin injection. The present study demonstrates that hepcidin deficiency causes increased Fe absorption. The effects of hepcidin were abolished by dietary Fe deficiency, indicating that the response to hepcidin may be influenced by dietary Fe level or Fe status.
Intestinal barrier function and absorption in pigs after weaning: a review
Authors: Wijtten Peter J. A. , Meulen Jan van der , Verstegen Martin W. A.
Published: February 2011

Under commercial conditions, weaning of piglets is associated with social, environmental and dietary stress. Consequently, small-intestinal barrier and absorptive functions deteriorate within a short time after weaning. Most studies that have assessed small-intestinal permeability in pigs after weaning used either Ussing chambers or orally administered marker probes. Paracellular barrier function and active absorption decrease when pigs are weaned at 3 weeks of age or earlier. However, when weaned at 4 weeks of age or later, the barrier function is less affected, and active absorption is not affected or is increased. Weaning stress is a critical factor in relation to the compromised paracellular barrier function after weaning. Adequate feed intake levels after weaning prevent the loss of the intestinal barrier function. Transcellular transport of macromolecules and passive transcellular absorption decrease after weaning. This may reflect a natural intestinal maturation process that is enhanced by the weaning process and prevents the pig from an antigen overload. It seems that passive and active absorption after weaning adapt accurately to the new environment when pigs are weaned after 3 weeks of age. However, when weaned at 3 weeks of age or earlier, the decrease in active absorption indicates that pigs are unable to sufficiently adapt to the new environment. To improve weaning strategies, future studies should distinguish whether the effect of feed intake on barrier function can be directed to a lack of a specific nutrient, i.e. energy or protein.
Effect of feeding Atlantic salmon (Salmo salar L.) a diet enriched with stearidonic acid from parr to smolt on growth and n-3 long-chain PUFA biosynthesis
Authors: Codabaccus Mohamed B. , Bridle Andrew R. , Nichols Peter D. , Carter Chris G.
Published: February 2011

Vegetable oils (VO) have become the predominant substitute for fish oil (FO) in aquafeeds; however, the resultant lower content of n-3 long-chain ( ≥ C20) PUFA (n-3 LC-PUFA) in fish has put their use under scrutiny. The need to investigate new oil sources exists. The present study tested the hypothesis that in Atlantic salmon (Salmo salar L.), a high intake of stearidonic acid (SDA) from Echium oil (EO) would result in increased n-3 LC-PUFA biosynthesis due to a lower requirement for Δ6 desaturase. Comparisons were made with fish fed on diets containing rapeseed oil (RO) and FO in freshwater for 112 d followed by 96 d in seawater. EO fish had higher whole-carcass SDA and eicosatetraenoic acid (ETA) in freshwater and prolonged feeding on the EO diet in seawater resulted in higher SDA, ETA, EPA and docosapentaenoic acid (DPA) compared with RO fish. Fatty acid mass balance of freshwater fish indicated higher biosynthesis of ETA and EPA in EO fish compared with fish fed on the other diets and a twofold increase in n-3 LC-PUFA synthesis compared with RO fish. In seawater, n-3 biosynthetic activity was low, with higher biosynthesis of ETA in EO fish and appearance of all desaturated and elongated products along the n-3 pathway. SDA-enriched VO are more suitable substitutes than conventional VO from a human consumer perspective due to the resulting higher SDA content, higher total n-3 and improved n-3:n-6 ratio obtained in fish, although both VO were not as effective as FO in maintaining EPA and DHA content in Atlantic salmon.
Adherence to a Mediterranean diet and plasma fatty acids: data from the Bordeaux sample of the Three-City study
Authors: Féart Catherine , Torrès Marion J. M. , Samieri Cécilia , Jutand Marthe-Aline , Peuchant Evelyne , Simopoulos Artemis P. , Barberger-Gateau Pascale
Published: February 2011

Higher adherence to a Mediterranean diet (MeDi) and n-3 PUFA may both contribute to decreased dementia risk, but the association between MeDi adherence and lipid status is unclear. The aim of the present study was to analyse the relationship between plasma fatty acids and MeDi adherence in French elderly community dwellers. The study population (mean age 75·9 years) consisted of 1050 subjects from Bordeaux (France) included in the Three-City cohort. Adherence to the MeDi (scored as 0–9) was computed from a FFQ and 24 h recall. The proportion of each plasma fatty acid was determined. Cross-sectional analysis of the association between plasma fatty acids and MeDi adherence was performed by multi-linear regression. After adjusting for age, sex, energy intake, physical activity, smoking status, BMI, plasma TAG and apoE-ɛ4 genotype, plasma palmitoleic acid was significantly inversely associated with MeDi adherence, whereas plasma DHA, the EPA+DHA index and total n-3 PUFA were positively associated with MeDi adherence. The n-6:n-3 PUFA, arachidonic acid (AA):EPA, AA:DHA and AA:(EPA+DHA) ratios were significantly inversely associated with MeDi adherence. Plasma EPA was positively associated with MeDi adherence only in apoE-ɛ4 non-carriers. There was no association between MeDi adherence and SFA and total MUFA. The present results suggest that the protective effect of the MeDi on cognitive functions might be mediated by higher plasma DHA and lower n-6:n-3 PUFA ratios.
International Politics and the Spread of Quotas for Women in Legislatures
Authors: Bush Sarah Sunn
Published: February 2011

Quotas to promote women's representation in the world's legislatures have spread to more than one hundred countries. The diffusion of gender quotas poses a puzzle since they have often been adopted in countries where women have low status. International influence and inducements best explain quota adoption in developing countries. Promoting gender equality, including through gender quotas, has become a key part of international democracy promotion. The international legitimacy of gender quotas leads them to be adopted through two causal pathways: directly, through postconflict peace operations, and indirectly, by encouraging countries, especially those that depend on foreign aid, to signal their commitment to democracy by adopting quotas. An event history analysis, which controls for other relevant factors, shows that the hypothesized relationships exist. Further support comes from a process-tracing analysis of Afghanistan's 2004 quota.