bluuebunny/crossref_metadata_2025 huggingface dataset:
Bone mineral density loss in relation to the final menstrual period in a multiethnic cohort: Results from the Study of Women's Health Across the Nation (SWAN)
Authors: Greendale Gail A , Sowers MaryFran , Han Weijuan , Huang Mei-Hua , Finkelstein Joel S , Crandall Carolyn J , Lee Jennifer S , Karlamangla Arun S
Published: October 2011

The objective of this study was to describe the time of onset and offset of bone mineral density (BMD) loss relative to the date of the final menstrual period (FMP); the rate and amount of BMD decline during the 5 years before and the 5 years after the FMP; and the independent associations between age at FMP, body mass index (BMI), and race/ethnicity with rates of BMD loss during this time interval. The sample included 242 African American, 384 white, 117 Chinese, and 119 Japanese women, pre- or early perimenopausal at baseline, who had experienced their FMP and for whom an FMP date could be determined. Loess-smoothed curves showed that BMD loss began 1 year before the FMP and decelerated (but did not cease) 2 years after the FMP, at both the lumbar spine (LS) and femoral neck (FN) sites. Piecewise, linear, mixed-effects regression models demonstrated that during the 10-year observation period, at each bone site, the rates and cumulative amounts of bone loss were greatest from 1 year before through 2 years after the FMP, termed the transmenopause. Postmenopausal loss rates, those occurring between 2 and 5 years after the FMP, were less than those observed during transmenopause. Cumulative, 10-year LS BMD loss was 10.6%; 7.38% was lost during the transmenopause. Cumulative FN loss was 9.1%; 5.8% was lost during the transmenopause. Greater BMI and African American heritage were related to slower loss rates, whereas the opposite was true of Japanese and Chinese ancestry. © 2012 American Society for Bone and Mineral Research
Retracted: Pro‐inflammatory cytokines induce odontogenic differentiation of dental pulp‐derived stem cells
Authors: Yang Xuechao , Zhang Siyuan , Pang Xin , Fan Mingwen
Published: October 2011

Retraction: The following article from Journal of Cellular Biochemistry, “Pro‐inflammatory cytokines induce odontogenic differentiation of dental pulp‐derived stem cells,” by Xuechao Yang, Siyuan Zhang, Xin Pang, and Mingwen Fan, published online on January 5, 2012 in Wiley Online Library (http://onlinelibrary.wiley.com), has been retracted by agreement between the authors, the journal Editor in Chief, Gary S. Stein and Wiley Periodicals, Inc. The retraction has been agreed due to overlap with the article published in Journal of Tissue Engineering and Regenerative Medicine, “Retracted: Effects of pro‐inflammatory cytokines on mineralization potential of rat dental pulp stem cells,” by Xuechao Yang, X. Frank Walboomers, Zhuan Bian, John A. Jansen, and Mingwen Fan published online on July 11, 2011.
Dynamic alterations in integrin α4 expression by hypoxia are involved in trophoblast invasion during early implantation
Authors: Na Kyu‐Hwan , Lee Hyun‐Jung , Choi Jong‐Ho , Eun Jung‐Woo , Nam Suk‐Woo , Yoon Tae‐Ki , Kim Gi‐Jin
Published: October 2011

Implantation of the blastocyst into the maternal endometrium is mediated by a population of well‐differentiated primary cells of the placenta known as trophoblasts, which grow in an invasive and destructive fashion similar to tumor cells. Interactions between the endometrium and trophoblasts are regulated by a coordinated interplay of extracellular matrix (ECM) proteins secreted by the invading extravillous trophoblasts. Integrins act as adhesion receptors and mediate both cell–ECM and cell–cell interactions. However, the correlation between integrin expression and trophoblast invasion under hypoxia is unclear. Here, we analyzed the expression of integrins in HTR‐8/SVneo trophoblast cells exposed to hypoxic conditions in order to demonstrate an association between invasion activity and integrin expression in trophoblasts. Trophoblasts were examined by microarray analysis, RT‐PCR, western blotting, and zymography after 1% hypoxic treatment, and cell invasion was estimated. The dynamic expression of integrins and human matrix metalloproteinases (MMPs) was observed under hypoxic conditions. The invasiveness of trophoblasts cultured under 1% hypoxic conditions was significantly greater than that of trophoblasts cultured under normoxic conditions through alterations in MMP‐2 and ‐9 (P < 0.05). Notably, integrin α4 expression during early hypoxia was negatively regulated by hypoxia‐inducible factor‐1alpha (HIF‐1alpha) expression in trophoblasts. The downregulation of integrin α4 expression by siRNA treatment controlled trophoblast invasion activity (P < 0.05). Taken together, we suggest that dynamic changes in integrins, including those in integrin α4 expression by hypoxia, play a regulatory role in trophoblast invasion. These findings expand our understanding of the potential roles of integrin α4 in implantation. J. Cell. Biochem. 113: 685–694, 2012. © 2011 Wiley Periodicals, Inc.
Biosynthesis of glucose‐d‐13C6 from Hansenula polymorpha and methanol‐13C
Authors: Liu Zhan‐feng , Ren Zheng , Xu Da‐gang , Li Liang‐jun
Published: October 2011

A simple and effective method for synthesis of glucose‐d‐13C6 by fermentation using the methylotrophic yeast Hansenula polymorpha with 99% abundance methanol‐13C is described. Using methanol‐13C as a sole source of carbon, H. polymorpha can accumulate large amounts of α,α‐trehalose‐13C12 under unfavourable growth conditions; the trehalose can then be hydrolysed to give glucose‐d‐13C6 with 98.5% abundance 13C. Copyright © 2011 John Wiley & Sons, Ltd.
Role of gap junctions in chronic pain
Authors: Wu Ann , Green Colin R. , Rupenthal Ilva D. , Moalem‐Taylor Gila
Published: October 2011

Gap junctions are specialized transmembrane channels that allow rapid electrical signalling and direct intercellular communication for maintenance and coordination of normal cellular activities and homeostasis. Although gap junction channels in the nervous system mediate intercellular coupling between glial cells and between neurons, they also contribute to the spread of secondary damage and inflammation under pathological conditions. There is now evidence of the involvement of gap junctions in chronic pain caused by nervous system damage or tissue inflammation. In this Mini‐Review, we highlight recent studies demonstrating the dynamic plasticity of gap junctions in response to nervous system injury and the effects of gap junction blockade on neuronal survival and modulation of pain in animal models of neuropathic and inflammatory pain. The involvement of dorsal root ganglia and spinal cord gap junctions in mediating chronic pain and the potential for targeting connexins as a novel modality for the treatment of intractable pain syndromes arising from nervous system injury and disorders are discussed. © 2011 Wiley Periodicals, Inc.
Toll‐like receptors 2 and 3 agonists differentially affect oligodendrocyte survival, differentiation, and myelin membrane formation
Authors: Bsibsi Malika , Nomden Anita , van Noort Johannes M. , Baron Wia
Published: October 2011

Toll‐like receptors (TLRs) play a key role in controlling innate immune responses to a wide variety of pathogen‐associated molecules as well as endogenous signals. In addition, TLR expression within nonimmune cells has been recognized as as modulator of cell behavior. In this study we have addressed the question of whether functional TLRs are expressed on oligodendrocytes, the myelinating cells of the central nervous system. Primary cultures of rat oligodendrocytes at different maturation stages were found to express TLR2 and, to lesser extent, TLR3. Immunocytochemical analysis revealed that both TLRs were localized at the cell body and primary processes and were excluded from myelin‐like membranes. Interestingly, innate immune receptor ligands were able to modulate oligodendrocyte survival, differentiation, and myelin‐like membrane formation, indicating that TLRs on oligodendrocytes are functional. In highly purified oligodendrocytes cultures, the TLR2 agonist zymosan promoted survival, differentiation, and myelin‐like membrane formation, whereas poly‐I:C, a TLR3 ligand, was a potent inducer of apoptosis. Together, these data indicate that, in addition to other neural cell types, also oligodendrocytes express functional TLRs, which play a role in regulating various aspects of oligodendrocyte behavior. © 2011 Wiley Periodicals, Inc.
Preparation of hydrophilic polymer‐grafted polystyrene beads for hydrophilic interaction chromatography via surface‐initiated atom transfer radical polymerization
Authors: Dai Xiaojun , He Yuan , Wei Yinmao , Gong Bolin
Published: October 2011

A one‐step procedure based on surface‐initiated atom transfer radical polymerization (SI‐ATRP) to hydrophilize monodisperse poly(chloromethylstyrene‐co‐divinylbenzene) beads has been presented in this work, using 2‐hydroxyl‐3‐[4‐(hydroxymethyl)‐1H‐1,2,3‐triazol‐1‐yl]propyl 2‐methylacrylate (HTMA) as a monomer. The chain length of the grafted poly(HTMA) was controlled via varying the ratio of HTMA to initiator on the surface of the beads. When using the grafted beads as a stationary phase in hydrophilic interaction chromatography (HILIC), good resolution for nucleobases/nucleosides was obtained with acetonitrile aqueous solution as an eluent; while for phenolic acids and glycosides, they could be eluted and separated in the presence of TFA. The retention time of the solutes increased with the amount of the grafted HTMA. The retention mechanisms of solutes were investigated by the effects of mobile phase composition and buffer pH on the retention of solutes. The results illustrated that the retention behaviors of the tested solutes were dominated by hydrogen bonding interaction and electrostatic interaction. From the chemical structure of the ligands, the modified beads could not only be used as a stationary phase in HILIC, but also act as a useful building block to develop new stationary phases for other chromatographic modes such as affinity media.
Enantioselective micro‐2D‐HPLC determination of aspartic acid in the pineal glands of rodents with various melatonin contents
Authors: Han Hai , Miyoshi Yurika , Oyama Tsubasa , Konishi Ryoko , Mita Masashi , Hamase Kenji
Published: October 2011

Enantioselective determination of aspartic acid (Asp) in the pineal gland of rodents with various melatonin contents was performed using a highly sensitive and selective two‐dimensional HPLC system. After derivatization of the amino group with 4‐fluoro‐7‐nitro‐2,1,3‐benzoxadiazole (NBD‐F), NBD‐Asp was separated using a capillary monolithic ODS column in the first dimension. The fraction of NBD‐Asp was automatically collected and transferred to the second dimension, and the D‐ and L‐Asp were separated and determined using a narrowbore enantioselective column. Large amounts of D‐Asp were observed in the pineal gland of the rats and specific strains of mice (C3H and CBA) possessing a high concentration of melatonin in their pineal gland. On the other hand, the amounts of D‐Asp were small in the pineal gland of mice possessing a trace or no melatonin in their pineal gland (ddY, ICR, C57BL and BALB/c). In other tissues and physiological fluids, no significant strain‐dependent changes of the D‐Asp amounts were observed. These results indicate that large amounts of D‐Asp are present only in the pineal gland containing large amounts of melatonin, and special care should be taken when selecting mouse strains for the investigation of D‐Asp.
Magnetic solid‐phase extraction using magnetic hypercrosslinked polymer for rapid determination of illegal drugs in urine
Authors: Gao Qiang , Lin Cai‐Yong , Luo Dan , Suo Li‐Li , Chen Jian‐Li , Feng Yu‐Qi
Published: October 2011

A novel magnetic material Fe3O4/SiO2/P(MAA‐co‐VBC‐co‐DVB) was prepared via the hypercrosslinking of its precursor which was produced via precipitation polymerization of methacrylic acid (MAA), vinylbenzyl chloride (VBC), and divinylbenzene (DVB) in the presence of Fe3O4/SiO2 submicrospheres with the surface containing abundant reactive double bonds. The resultant sorbent was characterized by scan electron microscopy, N2 adsorption, and Fourier transform infrared spectroscopy. It was found that this material had remarkable features such as large surface area (500 m2/g) and pore volume (0.32 cm3/g), as well as desirable chemical composition (including hydrophobic and ion‐exchange moieties). Taking advantages of the Fe3O4/SiO2/P(MAA‐co‐VBC‐co‐DVB), a magnetic SPE (MSPE) coupled with capillary electrophoresis (CE) method was developed for the determination of illegal drugs in urine samples. The extraction time could be clearly shortened up to 3 min. The recoveries of these drug compounds were in the range of 84.0–123% with relative standard deviations ranging between 1.7 and 10.5%; the limit of detection was in the range of 4.0–6.0 μg/L. The proposed method is simple, effective, and low‐cost, and provides an accurate and sensitive detection platform for abused drug analysis.
Heparin‐Like Macromolecules for the Modification of Anticoagulant Biomaterials
Authors: Ran Fen , Nie Shengqiang , Li Jie , Su Baihai , Sun Shudong , Zhao Changsheng
Published: October 2011

A heparin‐like structured macromolecule (HLSM) is synthesized by RAFT polymerization using carboxyl‐terminated trithiocarbonate as the RAFT agent. The HLSM can be directly blended with PES in DMAC to prepare flat‐sheet membrane by means of a liquid–liquid phase separation technique. The synthesized polymeric material retard blood clotting and the modified membrane exhibits good anticoagulant ability due to the existence of the important functional groups SO3H, COOH and OH. The anionic groups on the membrane surface may bind coagulation factors and thus improve anticoagulant ability. The results indicate that the HLSM has potential to improve the anticoagulant properties of biomaterials and to be applied in blood purification including hemodialysis and bioartificial liver supports.

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Notch2‐induced COX‐2 expression enhancing gastric cancer progression
Authors: Tseng Yun‐Chien , Tsai Yu‐Hui , Tseng Min‐Jen , Hsu Kai‐Wen , Yang Min‐Chieh , Huang Kuo‐Hung , Li Anna Fen‐Yau , Chi Chin‐Wen , Hsieh Rong‐Hong , Ku Hung‐Hai , Yeh Tien‐Shun
Published: October 2011

Gastric carcinoma is one of the most common and mortal types of malignancy worldwide. To date, the mechanisms controlling its aggressiveness are not yet fully understood. Notch signal pathway can function as either an oncogene or a tumor suppressor in tumorigenesis. Four members (Notch1–4) of Notch receptors were found in mammals and each exhibits distinct roles in tumor progression. Previous study showed that the activated Notch1 receptor promoted gastric cancer progression through cyclooxygenase‐2 (COX‐2). This study addressed whether Notch2 signal pathway is also involved in gastric cancer progression. Constitutive expression of Notch2 intracellular domain (N2IC), the activated form of Notch2 receptor, promoted both cell proliferation and xenografted tumor growth of human stomach adenocarcinoma SC‐M1 cells. The colony formation, migration, invasion, and wound‐healing abilities of SC‐M1 cells were enhanced by N2IC expression, whereas these abilities were suppressed by Notch2 knockdown. Similarly, Notch2 knockdown inhibited cancer progressions of AGS and AZ521 gastric cancer cells. Expression of N2IC also caused epithelial–mesenchymal transition in SC‐M1 cells. Furthermore, N2IC bound to COX‐2 promoter and induced COX‐2 expression through a CBF1‐dependent manner in SC‐M1 cells. The ability of N2IC to enhance tumor progression in SC‐M1 cells was suppressed by knockdown of COX‐2 or treatment with NS‐398, a COX‐2 inhibitor. Moreover, the suppression of tumor progression by Notch2 knockdown in SC‐M1 cells was reversed by exogenous COX‐2 or its major enzymatic product PGE2. Taken together, this study is the first to demonstrate that the Notch2‐COX‐2 signaling axis plays an important role in controlling gastric cancer progression. © 2011 Wiley Periodicals, Inc.
Mikrosilica — ein Staub macht Karriere
Authors: Friede Bernd , Fidjestøl Per
Published: October 2011

Gibt es ein Mittel gegen Betonkrebs und die Zerstörung von Beton durch Meerwasser und Sulfatlösungen? Ja, allerdings nur prophylaktisch: Mikrosilica sorgt weltweit für langlebige Beton konstruktionen.
Ungestörtes Wachstum erwünscht
Authors: Groß Michael
Published: October 2011

Herbizide, gegen die Unkräuter resistent sind, und Insektizide, die Bienen schaden — Pflanzenschutzmittelhersteller müssen ihre Produktentwicklung überdenken. Statt weiterer Mittel gegen Schädlinge erforschen sie mit neuen gentechnischen Methoden Nutzpflanzen, die Angriffen besser widerstehen.
Welches Tier lieferte das Fleisch?
Authors: Bollig Klaus
Published: October 2011

Um Zusammensetzung und Herkunft eines Lebensmittels zu überprüfen — etwa ob das Fleisch im Hamburger tatsächlich vom Rind stammt — eignet sich die DNA‐Analyse über Polymerase‐Kettenreaktion mit anschließender Elektrophorese. Diese lässt sich mit Mikrochiptechnik automatisieren.
Multiscale poro‐creep model for cement‐based materials
Authors: Gu Shui‐Tao , Bary Benoît , He Qi‐Chang , Thai Minh‐Quan
Published: October 2011

Experimental observations clearly show that the relative humidity (hr) conditions influence significantly the creep behavior of cement‐based materials, indicating that the water present within these materials plays a crucial role. This work presents a creep model for hardened cement pastes (HCP), based on a multiscale homogenization approach. It takes into account both free and adsorbed water contained in the porosity and investigates their effects on the HCP macroscopic creep behavior. The calcium silicate hydrate phase is assumed to be linear viscoelastic, and the Mori–Tanaka scheme is applied in the Laplace–Carson space to the composite formed of porosity, calcium silicate hydrate, and the other main hydrated compounds (which behavior is linearly elastic) by making use of the correspondence principle. With this model, estimations of the evolution of the macroscopic creep behavior of HCP submitted to constant external loading are examined under different hr and compared with available experimental data. Finally, a method for implementing the model in a finite element code is proposed, and simulations of standard creep tests are performed to assess its validity. Copyright © 2011 John Wiley & Sons, Ltd.
Capturing the Structure of Distinct Types of Individual Differences in the Situation–Specific Experience of Emotions: The Case of Anger
Authors: Ceulemans Eva , Kuppens Peter , Van Mechelen Iven
Published: October 2011

The aim of this paper was to understand why some people experience certain emotions in a specific situation, whereas others do not. We postulate that these individual differences arise from individual differences in two underlying processes of emotion elicitation: (i) individual differences in the emotion components (appraisals and action tendencies) that situations activate in a person and (ii) individual differences in how these emotion components are related to subjective emotional experience. In this paper, we re–analysed data from two studies on anger to capture the structure of these two types of individual differences by using clustering modelling techniques. Consistent results across the two studies demonstrated that individuals differ in anger because they (i) differ in how easy they experience anger–relevant appraisals (Studies 1 and 2) and action tendencies (Study 2) in increasingly negative situations and (ii) differ in which of these components are necessary to experience anger. Copyright © 2011 John Wiley & Sons, Ltd.
What goes up does not always come down: patterns of distress, physical and psychosocial morbidity in people with cancer over a one year period
Authors: Carlson Linda E. , Waller Amy , Groff Shannon L. , Giese‐Davis Janine , Bultz Barry D.
Published: October 2011

Background

As the concept of distress as the 6th vital sign gains strength in cancer care, research on the experience of patients is critical. This study longitudinally examined patients' physical and psychosocial concerns over the year following diagnosis.

Methods

Between July 2007 and February 2008, patients attending a large tertiary cancer centre were recruited to participate in a study examining their levels of distress, pain, fatigue, depression and anxiety over a year.

Results

A total of 877 patients provided baseline data with 620, 589 and 505 retained at 3, 6 and 12 months, respectively. Overall, levels of distress, depression and anxiety decreased significantly over the study period. No significant changes were found in levels of pain or fatigue. Demographics (being unmarried) and medical interventions (particularly having radiation therapy) predicted persistent distress, anxiety and depression, whereas receiving psychosocial support predicted decreased levels of distress, anxiety and depression. Some patients reported continued clinical levels of distress (29%), pain (19%) and fatigue (40%) 12 months post diagnosis.

Discussion

For some people, distress, depression, and anxiety may be transient and decrease over time, but for others they may be sustained. Pain and fatigue may remain present in many cancer patients. There is a need to modify current clinical practice to facilitate the appropriate assessment and management of distress. Copyright © 2011 John Wiley & Sons, Ltd.
Posttraumatic growth, social support, and social constraint in hematopoietic stem cell transplant survivors
Authors: Nenova Maria , DuHamel Katherine , Zemon Vance , Rini Christine , Redd William H.
Published: October 2011

Objective

The relation between posttraumatic growth (PTG) and aspects of the social context, such as social support and social constraint, continues to be unclear in cancer survivors. Social cognitive processing theory is a useful framework for examining the effect of the social context on PTG. In theory, support interactions may either facilitate or hinder cognitive processing and thus lead to different PTG outcomes. The current study tested the hypothesis that emotional support and instrumental support would each explain a unique amount of the variance in PTG in distressed hematopoietic stem cell transplant (HSCT) survivors. Additionally, it was predicted that social constraint on cancer‐related disclosure would be negatively associated with PTG.

Methods

Forty‐nine distressed HSCT survivors with a spouse or partner completed the posttraumatic growth inventory and measures of social support received from their spouse/partner and social constraint from people close to them as part of a larger clinical trial.

Results

Both emotional and instrumental social support were positively correlated with PTG, and social constraint on disclosure was not associated with PTG. Contrary to hypotheses, instrumental support was the only unique social contextual predictor of PTG.

Conclusions

The results of this study highlight the importance of examining the effects of subtypes of social support on PTG separately. Findings are discussed in the context of the cognitive (i.e., processing of the traumatic event) versus non‐cognitive (i.e., buffering stress) pathways between the social context and PTG. Future research directions are presented. Copyright © 2011 John Wiley & Sons, Ltd.
Multicentre Trials for Decontamination of Fine‐Lumen PTFE Tubes Loaded with Bacterial Endospores by Low and Atmospheric Pressure Plasma
Authors: Schnabel Uta , Maucher Tanja , Köhnlein Johanna , Volkwein Wolfram , Niquet Rijana , Trick Iris , Stieber Manfred , Müller Michael , Werner Heinz‐Peter , Ehlbeck Jörg , Oehr Christian , Weltmann Klaus‐Dieter
Published: October 2011

Today more and more thermo‐labile medical devices are applied, which have to be decontaminated with low‐temperature sterilization methods. One method under development is the low‐temperature plasma. For the comparability of the antimicrobial efficacy of two low‐temperature plasma setups in fine‐lumen polytetrafluoroethylene (PTFE) tubes, independent of performer, round robin tests with Bacillus atrophaeus and Geobacillus stearothermophilus spores loaded with 0.3% BSA were done. All in all six test series were necessary to standardize the process and to achieve comparability, reproducibility, and microbiological variability. The results provide new evidence to the importance of standardization in microbiological investigations in terms of decontamination. This new tool is useable for established and new decontamination and sterilization equipment.

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Plasma‐Induced Death of HepG2 Cancer Cells: Intracellular Effects of Reactive Species
Authors: Yan Xu , Xiong Zilan , Zou Fei , Zhao Shasha , Lu Xinpei , Yang Guangxiao , He Guangyuan , Ostrikov Kostya (Ken)
Published: October 2011

Reports show that cold atmospheric‐pressure plasmas can induce death of cancer cells in several minutes. However, very little is presently known about the mechanism of the plasma‐induced death of cancer cells. In this paper, an atmospheric‐pressure plasma plume is used to treat HepG2 cells. The experimental results show that the plasma can effectively control the intracellular concentrations of ROS, NO and lipid peroxide. It is shown that these concentrations are directly related to the mechanism of the HepG2 death, which involves several stages. First, the plasma generates NO species, which increases the NO concentration in the extracellular medium. Second, the intracellular NO concentration is increased due to the NO diffusion from the medium. Third, an increase in the intracellular NO concentration leads to the increase of the intracellular ROS concentration. Fourth, the increased oxidative stress results in more effective lipid peroxidation and consequently, cell injury. The combined action of NO, ROS and lipid peroxide species eventually results in the HepG2 cell death.

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Antibacterial Surfaces and Coatings Produced by Plasma Techniques
Authors: Vasilev Krasimir , Griesser Stefani S. , Griesser Hans J.
Published: October 2011

Bacterial colonisation of synthetic materials surfaces is an important problem in many fields and consequently there have been considerable efforts over many decades to find solutions. This review discusses plasma‐based strategies for combating infections at biomedical implants and devices, caused by the attachment of bacteria and their subsequent biofilm formation on device surfaces. Plasma polymerisation and plasma treatment have become attractive modalities for developing antibacterial coatings and various strategies have been reported. Plasma polymers have been used as reservoirs loaded with antibacterial agents that are subsequently released. Plasma polymer layers can also serve as a diffusion barrier to control the release rate. Plasma‐modified surfaces are also utilised as functional coatings for attachment of biocidal or bacteriostatic molecules. A popular strategy continues to be the use of silver ions or silver nanoparticles in polymer matrices. Another popular approach comprises the use of quaternary amine compounds on surfaces. In both cases, antibacterial activity is indeed obtained, but damage to human cells and tissue remains a concern. Alternative approaches utilising the covalent immobilisation of antibiotic molecules are discussed. We also assess existing strategies and their potential usefulness.

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Recommended management of common STIs in general practice
Authors: Gupta Nadi , Kinghorn George
Published: October 2011

Early diagnosis and treatment of STIs alleviates symptoms, complications and the period of infectivity. Our Drug review describes the available treatment options for the most commonly encountered STIs, followed by sources of further information. Copyright © 2011 Wiley Interface Ltd
Green's function approach in the classical theory of thermoelectricity
Authors: Achilles Steven , Seifert Wolfgang , Trimper Steffen
Published: October 2011

The Green's function (GF) method is a powerful technique to describe non‐equilibrium processes under inclusion of a broad class of boundary and initial conditions. Based on the Onsager theory of non‐equilibrium the applicability of GFs is demonstrated to find the steady‐state solution for the thermoelectric behaviour in one dimension. The spatial temperature profile is represented by the GF even if the Onsager transport coefficients are likewise coordinate dependent. The method can be directly used to study situations which are realized experimentally. The method can be extended to construct a systematic perturbation theory where the GF obeys a Dyson equation.
Materials with perpendicular magnetic anisotropy for magnetic random access memory
Authors: Sbiaa R. , Meng H. , Piramanayagam S. N.
Published: October 2011

Materials with perpendicular magnetic anisotropy (PMA) are being investigated for magnetic random access memory (MRAM) and other spintronics applications. This article is an overview of the developments in this topic. At first, a historical overview of the magnetic memory is presented along with the fundamentals of MRAM using the field‐assisted scheme. Later on, the principle of spin‐transfer torque (STT) is explained briefly along with the STT‐MRAM design requirements. Here, it is described that the MRAM design is a challenge where a choice has to be made to meet five criteria, a phenomenon called MRAM pentalemma. The main part of the article focuses on the discussion of materials with PMA. The focus is made first on multilayers such as Co/Pd and Co/Pt which have been widely investigated, followed by the recent observation of PMA in FeCoB. In subsequent sections, the progress in future candidates such as FePt is discussed. The article concludes with a summary of the challenges and future directions in this research topic. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Silicon: the gulf between crystalline and amorphous
Authors: Drabold D. A.
Published: October 2011

The Expert Opinion is written by a distinguished scientist and presents his personal view on important and relevant new results of research, highlighting their significance and putting the work into perspective for a broader audience. Please send comments to pss.rapid@wiley‐vch.de or to the author. The text by D. A. Drabold refers to the Rapid Research Letter by F. Kail et al., published in this issue of Phys. Status Solidi RRL 5(10–11), 361–363 (2011). (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Wild Mediterranean Dietary Plants as Inhibitors of Pancreatic Lipase
Authors: Conforti Filomena , Perri Valentina , Menichini Federica , Marrelli Mariangela , Uzunov Dimitar , Statti Giancarlo A. , Menichini Francesco
Published: October 2011

Lipids are essential compounds for all living organisms. Agents that inhibit fat digestion are of theoretical benefit in the treatment of obesity. A total of 18 species (21 hydroalcoholic extracts) of edible plants from Calabria region (Italy) were evaluated for their in vitro pancreatic lipase inhibitory activity. Lipase activity was measured by monitoring the hydrolysis of p‐NPC, which releases the yellow chromogen, p‐nitrophenol. The aqueous ethanol extracts of Portulaca oleracea (leaves) and Silene vulgaris (leaves) exhibited the strongest inhibitory effect on lipase. The amounts of total phenolics, measured by Folin‐Ciocalteu method, varied widely in the different analysed extracts and ranged from 29 to 482 mg/g of extract. In this study, the findings do not show any relationship between lipase inhibitory activity and total phenolic content. Copyright © 2011 John Wiley & Sons, Ltd.
Impact of non‐smooth observation operators on variational and sequential data assimilation for a limited‐area shallow‐water equation model
Authors: Steward J. L. , Navon I. M. , Zupanski M. , Karmitsa N.
Published: October 2011

We investigate the issue of variational and sequential data assimilation with nonlinear and non‐smooth observation operators using a two‐dimensional limited‐area shallow‐water equation model and its adjoint. The performance of the four‐dimensional variational approach (4D‐Var: two dimensions plus time) compared with that of the maximum‐likelihood ensemble filter (MLEF), a hybrid ensemble/variational method, is tested in the presence of non‐smooth observation operators.

Following the work of Lewis & Overton and Karmitsa, we investigate minimization of the data‐assimilation cost functional using the limited‐memory Broyden–Fletcher–Goldfarb–Shanno (L‐BFGS) quasi‐Newton algorithm originally intended for smooth optimization and the limited‐memory bundle method (LMBM) algorithm specifically designed to address large‐scale non‐smooth minimization problems.

Numerical results obtained for the MLEF method show that the LMBM algorithm yields results superior to the L‐BFGS method. Results for 4D‐Var suggest that L‐BFGS performs well when the non‐smoothness is not extreme, but fails for non‐smooth functions with large Lipschitz constants. The LMBM method is found to be a suitable choice for large‐scale non‐smooth optimization, although additional work is needed to improve its numerical stability. Finally, the results and methodologies of 4D‐Var and MLEF are compared and contrasted. Copyright © 2011 Royal Meteorological Society
Ocean Rossby waves as a triggering mechanism for primary Madden–Julian events
Authors: Webber Benjamin G. M. , Matthews Adrian J. , Heywood Karen J. , Stevens David P.
Published: October 2011

The Madden–Julian Oscillation (MJO) is sporadic, with episodes of cyclical activity interspersed with inactive periods. However, it remains unclear what may trigger a Madden–Julian (MJ) event which is not immediately preceded by any MJO activity: a ‘primary’ MJ event. A combination of case‐studies and composite analysis is used to examine the extent to which the triggering of primary MJ events might occur in response to ocean dynamics. The case‐studies show that such events can be triggered by the arrival of a downwelling oceanic equatorial Rossby wave, which is shown to be associated with a deepening of the mixed layer and positive sea‐surface temperature (SST) anomalies of the order of 0.5–1 °C. These SST anomalies are not attributable to forcing by surface fluxes which are weak for the case‐studies analysed. Furthermore, composite analysis suggests that such forcing is consistently important for triggering primary events. The relationship is much weaker for successive events, due to the many other triggering mechanisms which operate during periods of cyclical MJO activity. This oceanic feedback mechanism is a viable explanation for the sporadic and broadband nature of the MJO. Additionally, it provides hope for forecasting MJ events during periods of inactivity, when MJO forecasts generally exhibit low skill. Copyright © 2011 Royal Meteorological Society
On the feasibility of a fast forward model for Doppler interferometry in the infrared
Authors: Turner D. S. , Rochon Y. J.
Published: October 2011

A fast forward radiative transfer model to compute the emitted limb radiances for use in recovering line‐of‐sight Doppler winds from thermal line emission has been developed and evaluated. This study was formulated around the Stratospheric Wind Interferometer for Transport Studies (SWIFT) instrument—a limb imaging, field widened, phase‐stepping Michelson interferometer. The fast forward model is required to simulate a four‐point interferogram from which line‐of‐sight winds may be computed. The model, RT‐SWIFT (Radiative Transfer for SWIFT), is part of an effort to develop the capability of providing simultaneous measurements of horizontal wind velocity vectors and ozone concentration in the stratosphere for improving our understanding of global stratospheric dynamics and for studies in ozone transport.

Based in part on RT‐MIPAS (Radiative Transfer for the Michelson Interferometer for Passive Atmospheric Sounding), RT‐SWIFT uses a linear regression algorithm to parametrize the effective layer optical depths and can simulate the effect of variable ozone, nitrous oxide, water vapour and atmospheric winds. Trace gases are included as fixed climatological profiles.

The model development involved the selection of two suitable databases consisting of appropriate atmospheric absorber and wind profiles, and the accurate line‐by‐line modelling of their transmittances; one for generating regression coefficients and one consisting of simulated measurements for independent evaluation. The development also required selecting suitable predictors for the absorbers, winds and viewing geometry.

One‐dimensional inversion results using RT‐SWIFT with simulated measurements indicate that the model leads to wind and ozone error levels of about 3 to 5 m s−1 and 3 to 15% respectively for altitudes above ∼24 km. While further investment in model development and optimization is warranted, this demonstration study indicates that a sufficiently accurate fast forward model for near real‐time assimilation, and inversion, of horizontal Doppler wind measurements from thermal line emission is feasible. © 2011 Crown in the right of Canada. Published by John Wiley & Sons Ltd.
A regulated localization scheme for ensemble‐based Kalman filters
Authors: Nerger Lars , Janjić Tijana , Schröter Jens , Hiller Wolfgang
Published: October 2011

Localization is an essential element of ensemble‐based Kalman filters in large‐scale systems. Two localization methods are commonly used: covariance localization and domain localization. The former applies a localizing weight to the forecast covariance matrix, while the latter splits the assimilation into local regions in which independent assimilation updates are performed. The domain localization is usually combined with observation localization, which is a weighting of the observation‐error covariance matrix, resulting in a similar localization effect to that of covariance localized filters. It is shown that the use of the same localization function in covariance localization and observation localization results in distinct effective localization length‐scales in the Kalman gain. In order to improve the performance of observation localization, a regulated localization scheme is introduced. Twin experiments with the Lorenz‐96 model demonstrate that the regulated localization can lead to a significant reduction of estimation errors as well as increased stability of the assimilation process. Copyright © 2011 Royal Meteorological Society
Freeze‐drying of articular cartilage: Investigation of rat femoral heads by SEM
Authors: Draenert D. R. Y. , Draenert K.
Published: October 2011

The results of comparative investigations of freeze‐drying of joint cartilage which had not been separated from the underlying bone are reported.

Fixation and ethanol and amyl acetate substitution procedures cause marked loss of ground substance and thus create surface structures which are not present to the same degree in cartilage which is simply freeze‐dried. Indeed, it is questionable whether these structures are present in vivo. They were most highly developed in critical‐point‐dried cartilage.

The main difficulty with freeze‐drying is the prevention of damage caused by ice crystals. A tissue temperature of −130°C should always be aimed for and, because of the rapid growth of ice crystals, the temperature should never be allowed to rise above −90°C. These conditions can be fulfilled if the specimen is in good thermal contact with the cold stage and if the cooling device is equipped with a condenser which is cooled with liquid nitrogen.

The better the tissue was processed, the smoother was the resulting cartilage surface and the greater was the degree to which the chondrocytes fitted the walls of their lacunae.

At tissue temperatures above −90°C, the first change which became apparent was destruction of the cell membranes. This was followed by almost complete elution of the ground substance from between the fibers and, finally, the cell nuclei were also destroyed. This damage caused by ice crystals exposed fibrous structures on the surface of the cartilage, and the appearance of these structures was superior to that produced by enzymatic methods of preparation. The disruption caused by freezing uncovered intracellular structures.
Minimum depth electron probe x‐ray microanalysis as a means for determining the sulphur content of the human hair surface
Authors: Swift J. A.
Published: October 2011

By using incident electron energies as low as 3 keV it has been shown both theoretically and practically that the maximum depth for the excitation of sulphur Kα x‐rays from a sulphur‐containing proteinaceous solid can be restricted to 110 nm. This approach has been used to determine the concentration of sulphur in the immediate surface of human hair, and more particularly associated with the A‐layer subcomponent of the hair cuticle. The value obtained was 11.8 weight % (± 0.92, n = 10).
Rasterelektronenmikroskopie: (2. Überarb. u. erw. Aufl.): Eine Einführung für Mediziner und Biologen
Authors: Schwarz W.
Published: October 2011

Scanning Electron Microscopy (2nd revised and enlarged ed.) An Introduction for Physicians and Biologists Ohnsorge, J., Holm, R., translated by Yeo, J. Georg Thieme Verlag, Stuttgart 1978 (164 pages, 143 figures, DM 64,‐) ISBN 3135023028
Ion etching in metallography
Authors: Pohl M. , Burchard W.‐G.
Published: October 2011

Ion etching has proved to be a highly suitable method of preparation for the investigation of special problems in materials. The advantages of ion etching lie especially in the ability to sputter various elements and compounds with differing rates of removal. Reactive sputtering has proved highly suitable for the selective removal of individual structure components. Cathode sputtering is well adapted for the purification of specimens, particularly those with pores and cracks.
Scanning electron microscope localization of zinc granules in the oyster ostrea angasi by backscattered electron imaging
Authors: Jablonski W. , Lytton D. G.
Published: October 2011

A method for rapid localization of the zinc granules in oyster tissue using SEM has been developed. The results are discussed in terms of electron backscattering coefficients η for tissue, carbon support and embedding medium. Also, the application of the presented method for marine environment pollution detection and monitoring is recommended.
Dynamic hydration studies in an SEM
Authors: Neal R. J. , Mills A.
Published: October 2011

A Cambridge Mark II Stereoscan SEM equipped with TV scan capabilities has been modified to study both static and dynamic interactions of water with water sensitive materials. The design and operation of this instrument to permit it to be used at 10°C temperature and 6.5 mbar specimen chamber pressure are included.

A study of the continuous interaction of water with a natural sponge is included to demonstrate the usefulness of the dynamic capability of this technology. A time‐lapse study of this hydration process shows how a sponge absorbs water. Micrographs of water freezing are also included. This instrument, which has a resolution of about 150 nm, can also be used for static studies of hydrated materials. We anticipate that this technology will be used to study many other dynamic and static liquid‐solid and liquid‐liquid interactions such as emulsions, detergency processes, crystallization, solubilization, and perhaps even living biological specimens.
Design and construction of an atmospheric or environmental SEM (part 3)
Authors: Danilatos G. D.
Published: October 2011

The continuation of the advances in designing and constructing an atmospheric or environmental SEM (ASEM and ESEM, respectively) is reported. A pair of scintillator backscattered electron detectors have been designed and made so that signal processing to enhance topography and Z‐contrast can be performed. Optimum shapes and positioning of the detectors have been determined. The light transmittance in the light pipe has been mapped and measured to be 51%. Satisfactory signal‐to‐noise ratio images of a carbon specimen have been obtained with 5 kV, 2 pA and 50s scan time at 0.1 mbar. With a higher intensity beam, clear images of wool fibres have been achieved at 1 bar pressure. The ASEM and ESEM have been shown to operate both under conditions of a gaseous environment and with detection modes used in other microscopes. Changes and phenomena occurring as the relative humidity varies between 0 and 100% have been recorded.
High‐angle annular dark‐field STEM imaging of immunogold labels
Authors: Otten M. T. , Stenzel D. J. , Cousens D. R. , Humbel B. M. , Leunissen J.L. M. , Stierhof Y.‐D. , Busing W.M.
Published: October 2011

High‐angle annular dark‐field (HAADF) STEM imaging is a sensitive and efficient technique for detecting immunogold labels. Larger (5–15 nm) gold labels can be distinguished clearly from the heavy metal stain on tissue sections, but for smaller (<5 nm) labels the distinction is less clear. It is not possible to differentiate between ultra‐small (<1–3 nm) labels and stain, but the HAADF image shows sufficient contrast so specimens can remain unstained. On a TEM/STEM equipped with a LaB6 filament the smallest labels that are detectable are 1–2 nm. Efficient detection of ultra‐small labels requires a field emission microscope.
A sampling monitor for applications programs
Authors: Waite W. M.
Published: October 2011

Periodic location counter sampling is a well‐known technique for conducting performance measurements on operating systems. It is also extremely useful for applications programs. This paper describes a set of interface conventions for such a monitor. SPY, a monitor obeying these conventions, has been implemented on three different computers.
Serious FORTRAN
Authors: Larmouth J.
Published: October 2011

This paper is based on a set of lectures given at Cambridge, directed to those who intend to write FORTRAN programs which have more than a transient life. This first part deals with the implications of conforming to the ANSI standard when writing FORTRAN. The second part, which will appear in the next issue, deals with the problem of producing optimal programs, debugging techniques and a number of miscellaneous topics.
The people's time sharing system
Authors: Tanenbaum Andrew S. , Benson William H.
Published: October 2011

A set of programs running under a multiprogramming batch operating system on the CDC 6600 which provide remote users with a time sharing service is described. The basis for the system is the ability of a user program to create job control statements during execution, thereby tricking the operating system into treating it as an ordinary batch job. The text editor and the interactive debugging facilities are described. The performance of the system, known as the People's Time Sharing System (PTSS), and user reaction to it are also described.
A note on recreating source code from the reverse polish form
Authors: Charlton C. C. , Hibbard P. G.
Published: October 2011

Algorithms are presented which recreate infix form from reverse Polish form of algebraic expressions. The use of these algorithms in incremental compilers is discussed.
Bootstrapping XPL to an XDS sigma 5 computer
Authors: Leach Geoffrey , Golde Hellmut
Published: October 2011

This paper describes the techniques used in bootstrapping the self‐compiling compiler for the language XPL from an IBM System/360 to an XDS Sigma 5.
A portable language for system development
Authors: Calderbank M. , Calderbank V. J.
Published: October 2011

The design and implementation of a system development language which is economical to implement is described. Both macro processing and compiling techniques are used to translate it. The advantages and disadvantages of using such a language are discussed together with the main problems met in its implementation.
Two examples of virtual records
Authors: Reavley P. A.
Published: October 2011

This paper contains an introduction to virtual records. Two examples of virtual record implementations are described in detail, and six other implementations are described briefly. The main purpose of virtual records is to reduce the effect on existing programs of changes in record content and format. The value of virtual records in this context is examined.