bluuebunny/crossref_metadata_2025 huggingface dataset:
Roles of silica and lignin in horsetail (Equisetum hyemale), with special reference to mechanical properties
Authors: Yamanaka Shigeru , Sato Kanna , Ito Fuyu , Komatsubara Satoshi , Ohata Hiroshi , Yoshino Katsumi
Published: March 2012

This research deals with detailed analyses of silica and lignin distribution in horsetail with special reference to mechanical strength. Scanning electron images of a cross-section of an internode showed silica deposited densely only around the outer epidermis. Detailed histochemical analyses of lignin showed no lignin deposition in the silica-rich outer internodes of horsetail, while a characteristic lignin deposition was noticed in the vascular bundle in inner side of internodes. To analyze the structure of horsetail from a mechanical viewpoint, we calculated the response of a model structure of horsetail to a mechanical force applied perpendicularly to the long axis by a finite element method. We found that silica distributed in the outer epidermis may play the major structural role, with lignin’s role being limited ensuring that the vascular bundle keep waterproof. These results were in contrast to more modern tall trees like gymnosperms, for which lignin provides mechanical strength. Lignin has the advantage of sticking to cellulose, hemicellulose, and other materials. Such properties make it possible for plants containing lignin to branch. Branching of tree stems aids in competing for light and other atmospheric resources. This type of branching was impossible for ancient horsetails, which relied on the physical properties of silica. From the evolutional view points, over millennia in trees with high lignin content, true branching, and many chlorophyll-containing leaves developed.
Theoretical model for artificial structure modulation of HfO2/SiOx/Si interface by deposition of a dopant material
Authors: Umezawa Naoto , Shiraishi Kenji
Published: March 2012

Realization of an abrupt HfO2/Si interface without unintentional oxidation of the silicon substrate is a crucial task for the development of modern field-effect transistors. Here, we present a theoretical model which suggests that deposition of a dopant material on the HfO2 layer turns it into an oxygen absorber, suppressing the formation of SiOx at the interface. Tantalum is predicted as an effective dopant in HfO2 for this purpose.
Modulating quantum transport by transient chaos
Authors: Yang Rui , Huang Liang , Lai Ying-Cheng , Pecora Louis M.
Published: March 2012

We propose a scheme to modulate quantum transport in nanostructures based on classical chaos. By applying external gate voltage to generate a classically forbidden region, transient chaos can be generated, and the escape rate associated with the underlying non-attracting chaotic set can be varied continuously by adjusting the gate voltage. We demonstrate that this can effectively modulate the quantum conductance-fluctuation patterns. A theory based on self-energies and the spectrum of the generalized non-Hermitian Hamiltonian of the open quantum system is developed to understand the modulation mechanism.
Stokes number effects on particle slip velocity in wall-bounded turbulence and implications for dispersion models
Authors: Zhao L. H. , Marchioli C. , Andersson H. I.
Published: March 2012

The particle slip velocity is adopted as an indicator of the behavior of heavy particles in turbulent channel flow. The statistical moments of the slip velocity are evaluated considering particles with Stokes number, defined as the ratio between the particle response time and the viscous time scale of the flow, in the range 1 < St < 100. The slip velocity fluctuations exhibit a monotonic increase with increasing particle inertia, whereas the fluid-particle velocity covariance is gradually reduced for St ⩾ 5. Even if this covariance equals the particle turbulence intensity, a substantial amount of particle slip may occur. Relevant to two-fluid modeling of particle-laden flows is the finding that the standard deviation of the slip velocity fluctuations is significantly larger than the corresponding mean slip velocity.
Optical and kinetic properties of the dusty plasma in radiofrequency discharge
Authors: Ramazanov T. S. , Jumabekov A. N. , Orazbayev S. A. , Dosbolayev M. K. , Jumagulov M. N.
Published: March 2012

Dependence of diffusion coefficient of dusty particles in dusty plasma was experimentally obtained. A proportional increase of diffusion of the dust particles with the increase of the discharge power was experimentally found. The pair correlation functions of dusty particles were also obtained from the experiments and the change of dust cloud structure with the increase of the discharge power was observed. The influence of the dust particles on the spectrum of plasma glow was investigated using spatial spectrometer. It was shown that upon introduction of dust particles into the plasma bulk the overall intensity of the plasma glow decreases.
Nonvolatile memory with graphene oxide as a charge storage node in nanowire field-effect transistors
Authors: Baek David J. , Seol Myeong-Lok , Choi Sung-Jin , Moon Dong-Il , Choi Yang-Kyu
Published: March 2012

Through the structural modification of a three-dimensional silicon nanowire field-effect transistor, i.e., a double-gate FinFET, a structural platform was developed which allowed for us to utilize graphene oxide (GO) as a charge trapping layer in a nonvolatile memory device. By creating a nanogap between the gate and the channel, GO was embedded after the complete device fabrication. By applying a proper gate voltage, charge trapping, and de-trapping within the GO was enabled and resulted in large threshold voltage shifts. The employment of GO with FinFET in our work suggests that graphitic materials can potentially play a significant role for future nanoelectronic applications.
Theoretical approach for plasma series resonance effect in geometrically symmetric dual radio frequency plasma
Authors: Bora B. , Bhuyan H. , Favre M. , Wyndham E. , Chuaqui H.
Published: March 2012

Plasma series resonance (PSR) effect is well known in geometrically asymmetric capacitively couple radio frequency plasma. However, plasma series resonance effect in geometrically symmetric plasma has not been properly investigated. In this work, a theoretical approach is made to investigate the plasma series resonance effect and its influence on Ohmic and stochastic heating in geometrically symmetric discharge. Electrical asymmetry effect by means of dual frequency voltage waveform is applied to excite the plasma series resonance. The results show considerable variation in heating with phase difference between the voltage waveforms, which may be applicable in controlling the plasma parameters in such plasma.
High-Q aluminum nitride photonic crystal nanobeam cavities
Authors: Pernice W. H. P. , Xiong C. , Schuck C. , Tang H. X.
Published: March 2012

We demonstrate high optical quality factors in aluminum nitride (AlN) photonic crystal nanobeam cavities. Suspended AlN photonic crystal nanobeams are fabricated in sputter-deposited AlN-on-insulator substrates using a self-protecting release process. Employing one-dimensional photonic crystal cavities coupled to integrated optical circuits, we measure quality factors up to 146 000. By varying the waveguide-cavity coupling gap, extinction ratios in excess of 15 dB are obtained. Our results open the door for integrated photonic bandgap structures made from a low loss, wide-transparency, nonlinear optical material system.
Viscous pressure-driven flows and their stability in channels with vertically oscillating walls
Authors: Espìn Leonardo , Papageorgiou Demetrios T.
Published: March 2012

We study viscous flows in infinitely long two-dimensional channels which are driven by vertical periodic oscillations of their rigid walls and a prescribed horizontal pressure gradient. Exact solutions of the Navier-Stokes equations exist for these flows in the sense that a coupled system of partial differential equations (involving time and the vertical coordinate alone) determines the solutions. The flow due to the vertical periodic wall oscillations is of stagnation point form (the horizontal velocity is linear in the horizontal coordinate x) and couples with the prescribed horizontal pressure gradient to produce a horizontal velocity which is x-independent. We investigate the solutions computationally for wide ranges of Reynolds numbers as the amplitude of the wall oscillations increases. It is found that the x-independent flow loses stability (Floquet theory is used to quantify this) at values of the Reynolds number below those required to drive the purely oscillatory flow into the chaotic regime. A similar bifurcation picture emerges when the pressure gradients are time oscillatory. In addition, computations show that when the wall and pressure oscillations are synchronous, their amplitudes can be used to produce a change in the sign of the net flux across the channel over one time period. The computations identify parameter regimes that achieve a desired direction and magnitude of the time-averaged net flux across the channel.
Grid-connected photovoltaic-systems design using evolutionary strategies
Authors: Gómez-Lorente Daniel , Alameda-Hernández Enrique , Aznar Dols F. , Espín Estrella A.
Published: March 2012

This paper addresses the problem of electrical losses that occur in the electrical conductors in photovoltaic (PV) plants with trackers. Thus, we propose a method which makes an optimal sizing and distribution of the elements that compose the PV to make the electrical losses by Joule effect as low as possible. To solve this problem, evolutionary algorithms implemented in matlab, have been used. Specifically the steady-state genetic algorithm (GA), the generational GA and the cross generational elitist selection, heterogeneous recombination and cataclism mutation (CHC) algorithm, which from random initial solutions, possibly far from optimal, will evolve into solutions that are increasingly closer to the desired optimum. Results have been very satisfactory, since all proposed examples have reduced by more than 40%, and CHC algorithm by more than 50%, electrical losses originated by not optimally designing the PV plant.
Dependence of surface free energy on molecular orientation in polymer films
Authors: Stachewicz Urszula , Li Shuangwu , Bilotti Emiliano , Barber Asa H.
Published: March 2012

Surface free energy of mechanically drawn polycarbonate films was determined using contact angle measurements and shown to increase with orientation. The increase in polymer film surface free energy was attributed to increased polymer chain packing during orientation, supported by film density measurements, which provides enhanced intermolecular interactions. Surface free energy can therefore be increased by, or used to predict, polymer orientation.
Attitudes to cosmetic surgery among ethnic minority groups in Britain: Cultural mistrust, adherence to traditional cultural values, and ethnic identity salience as protective factors
Authors: Swami Viren , Hendrikse Sinead
Published: March 2012

Previous work has suggested that ethnic minority women have more negative attitudes to cosmetic surgery than British Whites, but reasons for this are not fully understood. To overcome this dearth in the literature, the present study asked 250 British Asian and 250 African Caribbean university students to complete measures of attitudes to cosmetic surgery, cultural mistrust, adherence to traditional cultural values, ethnic identity salience, self‐esteem, and demographics. Preliminary analyses showed that there were significant between‐group differences only on cultural mistrust and self‐esteem, although effect sizes were small (d values = .21–.37). Further analyses showed that more negative attitudes to cosmetic surgery were associated with greater cultural mistrust, stronger adherence to traditional values, and stronger ethnic identity salience, although these relationships were weaker for African Caribbean women than for British Asians. These results are discussed in relation to perceptions of cosmetic surgery among ethnic minority women.
Scale- and Context-Dependent Selection of Recreational Harvest Estimation Methods: The Australasian Experience
Authors: Hartill Bruce W. , Cryer Martin , Lyle Jeremy M. , Rees Eugene B. , Ryan Karina L. , Steffe Aldo S. , Taylor Stephen M. , West Laurie , Wise Brent S.
Published: March 2012

Fisheries managers are becoming increasingly aware of the need to quantify all forms of harvest, including that by recreational fishers. This need has been driven by both a growing recognition of the potential impact that noncommercial fishers can have on exploited resources and the requirement to allocate catch limits between different sectors of the wider fishing community in many jurisdictions. Marine recreational fishers are rarely required to report any of their activity, and some form of survey technique is usually required to estimate levels of recreational catch and effort. In this review, we describe and discuss studies that have attempted to estimate the nature and extent of recreational harvests of marine fishes in New Zealand and Australia over the past 20 years. We compare studies by method to show how circumstances dictate their application and to highlight recent developments that other researchers may find of use. Although there has been some convergence of approach, we suggest that context is an important consideration, and many of the techniques discussed here have been adapted to suit local conditions and to address recognized sources of bias. Much of this experience, along with novel improvements to existing approaches, have been reported only in “gray” literature because of an emphasis on providing estimates for immediate management purposes. This paper brings much of that work together for the first time, and we discuss how others might benefit from our experience.

Received February 8, 2011; accepted October 13, 2011
Market Structure, Competition from Assisted Living Facilities, and Quality in the Nursing Home Industry
Authors: Bowblis John R.
Published: March 2012

The effort to provide more long‐term care in community‐based settings has caused an expansion in the supply of assisted living beds, yet little is known about the interrelationship between this expansion and nursing home quality. This paper studies data from the State of Ohio to determine if nursing home market structure and the expansion in the supply of assisted living beds impact the quality of care provided by nursing homes. The findings suggest that nursing home quality can be lower in markets with a greater supply of nursing homes. Further, assisted living facility market structure is found to have a mixed effect on nursing home quality. The results of this paper suggest a need for a more integrated approach to regulating long‐term care providers.
Rapid identification of non-human sequences in high-throughput sequencing datasets
Authors: Bhaduri Aparna , Qu Kun , Lee Carolyn S. , Ungewickell Alexander , Khavari Paul A.
Published: March 2012

Summary: Rapid identification of non-human sequences (RINS) is an intersection-based pathogen detection workflow that utilizes a user-provided custom reference genome set for identification of non-human sequences in deep sequencing datasets. In <2 h, RINS correctly identified the known virus in the dataset SRR73726 and is compatible with any computer capable of running the prerequisite alignment and assembly programs. RINS accurately identifies sequencing reads from intact or mutated non-human genomes in a dataset and robustly generates contigs with these non-human sequences (Supplementary Material).

Availability: RINS is available for free download at http://khavarilab.stanford.edu/resources.html

Contact:  abhaduri@stanford.edu or kqu@stanford.edu

Supplementary information:  Supplementary data are available at Bioinformatics online.
Bifidobacteria Isolated From Infants and Cultured on Human Milk Oligosaccharides Affect Intestinal Epithelial Function
Authors: Chichlowski Maciej , De Lartigue Guillaume , German J. Bruce , Raybould Helen E. , Mills David A.
Published: March 2012

Objectives:

Human milk oligosaccharides (HMOs) are the third most abundant component of breast milk. Our laboratory has previously revealed gene clusters specifically linked to HMO metabolism in selected bifidobacteria isolated from fecal samples of infants. Our objective was to test the hypothesis that growth of selected bifidobacteria on HMO stimulates the intestinal epithelium.

Methods:

Caco‐2 and HT‐29 cells were incubated with lactose (LAC)‐ or HMO‐grown Bifidobacterium longum subsp infantis (B infantis) or B bifidum. Bacterial adhesion and translocation were measured by real‐time quantitative polymerase chain reaction. Expression of pro‐ and anti‐inflammatory cytokines and tight junction proteins was analyzed by real‐time reverse transcriptase. Distribution of tight junction proteins was measured using immunofluorescent microscopy.

Results:

We showed that HMO‐grown B infantis had a significantly higher rate of adhesion to HT‐29 cells compared with B bifidum. B infantis also induced expression of a cell membrane glycoprotein, P‐selectin glycoprotein ligand‐1. Both B infantis and B bifidum grown on HMO caused less occludin relocalization and higher expression of anti‐inflammatory cytokine, interleukin‐10 compared with LAC‐grown bacteria in Caco‐2 cells. B bifidum grown on HMO showed higher expression of junctional adhesion molecule and occludin in Caco‐2 cells and HT‐29 cells. There were no significant differences between LAC or HMO treatments in bacterial translocation.

Conclusions:

The study provides evidence for the specific relation between HMO‐grown bifidobacteria and intestinal epithelial cells. To our knowledge, this is the first study describing HMO‐induced changes in the bifidobacteria–intestinal cells interaction.
In vivo and in vitro studies on the antiviral activities of viperin against influenza H1N1 virus infection
Authors: Tan Kai Sen , Olfat Farzad , Phoon Meng Chee , Hsu Jung Pu , Howe Josephine L. C. , Seet Ju Ee , Chin Keh Chuang , Chow Vincent T. K.
Published: March 2012

Influenza A virus has caused a number of pandemics in past decades, including the recent H1N1-2009 pandemic. Viperin is an interferon (IFN)-inducible protein of innate immunity, and acts as a broad-spectrum antiviral protein. We explored the antiviral activities and mechanisms of viperin during influenza virus (IFV) infection in vitro and in vivo. Wild-type (WT) HeLa and viperin-expressing HeLa cells were infected with influenza A/WSN/33/H1N1 (WSN33) virus, and subjected to virological, light and electron microscopic analyses. Viperin expression reduced virus replication and titres, and restricted viral budding. Young and old viperin-knockout (KO) mice and WT control animals were challenged with influenza WSN33 at lethal doses of 103 and 104 p.f.u. via the intratracheal route. Lungs were subjected to histopathological, virological and molecular studies. Upon lethal IFV challenge, both WT and KO mice revealed similar trends of infection and recovery with similar mortality rates. Viral quantification assay and histopathological evaluation of lungs from different time points showed no significant difference in viral loads and lung damage scores between the two groups of mice. Although the in vitro studies demonstrated the ability of viperin to restrict influenza H1N1 virus replication, the viperin-deficient mouse model indicated that absence of viperin enhanced neither the viral load nor pulmonary damage in the lungs of infected mice. This may be due to the compensation of IFN-stimulated genes in the lungs and/or the influenza non-structural protein 1-mediated IFN antagonism dampening the IFN response, thereby rendering the loss of viperin insignificant. Nevertheless, further investigations that exploit the antiviral mechanisms of viperin as prophylaxis are still warranted.
General Considerations for Live Imaging of Developing Hippocampal Neurons in Culture
Authors: Kaech Stefanie , Huang Chun-Fang , Banker Gary
Published: March 2012

Dissociated cell cultures of the rodent hippocampus have become a standard model for studying many facets of neural development, including the development of polarity, axonal and dendritic growth, and synapse formation. The cultures are quite homogeneous—∼90% of the cells are pyramidal neurons—and it is relatively easy to express green fluorescent protein (GFP)-tagged proteins by transfection. This article describes the cultures and the key features of the system used to image them. It also includes suggestions on labeling cells with GFP-tagged proteins. It concludes with a discussion of the advantages and disadvantages of this culture system.
Microdissection of Drosophila Polytene Chromosomes for DOP-PCR
Authors: Dernburg Abby F.
Published: March 2012

This protocol describes a method for the microdissection of Drosophila polytene chromosomes. The microdissected DNA can be amplified by degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR) and then used to prepare probes for fluorescent in situ hybridization (FISH).
Construction and Packaging of Herpes simplex Virus/Adeno-Associated Virus (HSV/AAV) Hybrid Amplicon Vectors
Authors: Saydam Okay , Glauser Daniel L. , Fraefel Cornel
Published: March 2012

Herpes simplex virus type 1 (HSV-1)-based amplicon vectors conserve most properties of the parental virus: broad host range, the ability to transduce dividing and nondiving cells, and a large transgene capacity. This permits incorporation of genomic sequences as well as cDNA, large transcriptional regulatory sequences for cell-specific expression, multiple transgene cassettes, or genetic elements from other viruses. Hybrid vectors use elements from HSV-1 that allow replication and packaging of large-vector DNA into highly infectious particles, and elements from other viruses that confer genetic stability to vector DNA in the transduced cell. For example, adeno-associated virus (AAV) has the unique ability to integrate its genome into a specific site on human chromosome 19. The viral rep gene and the inverted terminal repeats (ITRs) that flank the AAV genome are sufficient for this process. However, AAV-based vectors have a very small transgene capacity and do not conventionally contain the rep gene to support site-specific genomic integration. HSV/AAV hybrid vectors contain both HSV-1 replication and packaging functions and the AAV rep gene and a transgene cassette flanked by the AAV ITRs. This combines the large transgene capacity of HSV-1 with the capability of site-specific genomic transgene integration and long-term transgene expression of AAV. This protocol describes the preparation of HSV/AAV hybrid vectors using a replication-competent/conditional, packaging-defective HSV-1 genome cloned as a bacterial artificial chromosome (BAC) to provide helper functions for vector replication and packaging. The advantages and limitations of such vectors compared to standard HSV-1 amplicon vectors are also discussed.
Visualizing Single Molecules in Living Dictyostelium Cells Using Total Internal Reflection Fluorescent Microscopy (TIRFM)
Authors: Matsuoka Satomi , Miyanaga Yukihiro , Yanagida Toshio , Ueda Masahiro
Published: March 2012

Environmental changes result in signaling events at cell membranes. To develop the means to understand these events at the molecular level, it is essential to become familiar with the stochastic nature of signaling molecules in living cells. Using total internal reflection fluorescent microscopy (TIRFM), these signaling events can be directly observed at the single-molecule level. This protocol describes the procedure used for objective-type TIRFM to visualize single fluorescent molecules in living Dictyostelium cells, which are highly sensitive to chemoattractant stimulation. This method can also be applied to other cell types.
Long-Term Time-Lapse Imaging of Developing Hippocampal Neurons in Culture
Authors: Kaech Stefanie , Huang Chun-Fang , Banker Gary
Published: March 2012

Dissociated cell cultures of the rodent hippocampus have become a standard model for studying many facets of neural development. The cultures are quite homogeneous and it is relatively easy to express green fluorescent protein (GFP)-tagged proteins by transfection. Studying developmental processes that occur over many hours or days—for example, dendritic branching—involves capturing images of a cell at regular intervals without compromising cell survival. This approach is also useful for studying events of short duration that occur asynchronously across the cell population. For such studies, it is highly desirable to use a computer-controlled microscope with an automated stage, to follow multiple cells at different locations in the culture, moving sequentially from one to the next and capturing an image at each location. A method to correct for focal drift is also required. For long-term imaging, we culture neurons in a medium without phenol red, which is thought to give rise to toxic substances following exposure to light. To label cells with GFP-tagged proteins for long-term imaging, we usually use nucleofection (rather than lipid-mediated transfection); this gives a high transfection efficiency, which makes it easier to find the right cell for imaging. Our protocol for long-term imaging is given here, along with appropriate methods to express GFP-tagged proteins. Examples illustrate how the protocol can be used to image cytoskeletal dynamics during axon specification and to study kinesin motor dynamics in stage 2 neurons (when minor neurites extend).
Resilience of inshore, juvenile snapper Pagrus auratus to angling and release
Authors: Broadhurst M. K. , Butcher P. A. , Hall K. C. , Cullis B. R. , McGrath S. P.
Published: March 2012

This study assessed the mortality of 157 snapper Pagrus auratus (9–29 cm, total length, LT) after being conventionally angled and then released into cages (along with 48 controls) for 4 days off south‐eastern Australia. Fatalities were restricted to 12 angled fish (7·6%) and mostly attributed to the ingestion of hooks and especially their subsequent removal, which caused substantial blood loss and immediate death. Hook ingestion was significantly biased towards smaller fish (<21 cm LT) and attributed to a lower chance of anglers initially detecting these individuals on the line (allowing them to consume more of the baits). While mortalities might be reduced in future via (1) choosing terminal rigs that promote mouth hooking and (2) cutting the line on any‐hook ingested fish, the results nevertheless validate releasing unwanted angled inshore juvenile P. auratus as a means for managing their exploitation.
Influence of adult age on the total and free clearance and protein binding of (R)‐ and (S)‐warfarin
Authors: Jensen Berit Packert , Chin Paul Ken Leong , Roberts Rebecca Lee , Begg Evan James
Published: March 2012

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Hepatic drug clearance is thought to be reduced with age. However for highly protein bound drugs, which are cleared by capacity‐limited metabolism, studies on total clearance have been conflicting. The hypothesis that protein binding decreases with age has been used to explain this.

• Warfarin is a highly protein bound drug, which is cleared by capacity‐limited metabolism. There are conflicting or little data on the relationship between adult age and total and free clearance and protein binding of (R)‐ and (S)‐warfarin.

WHAT THIS STUDY ADDS

• In a clinical study of 72 patients (18–89 years) on warfarin therapy, both total and free clearance of (R)‐warfarin decreased with age. For (S)‐warfarin there was a stronger signal of a decrease in free than total clearance. Protein binding was found not to correlate with age for (R)‐ and (S)‐warfarin.

• In an ex vivo study, in which warfarin was spiked to plasma samples from 60 healthy subjects (19–87 years), no correlation between protein binding and age was found.

• These data support the hypothesis that hepatic drug clearance decreases with age. This should be taken into consideration when individualizing dosing, particularly in the elderly.

AIMS To test the hypothesis that the clearance (CL) of warfarin, a very highly protein bound drug with capacity‐limited metabolism, decreases with age.

METHODS In a clinical study, a steady‐state blood sample was taken from 72 patients (18–89 years) on routine treatment with warfarin. Concentrations of (R)‐ and (S)‐warfarin were determined in plasma (total) and ultrafiltrate (free) by LC‐MS/MS. Total and free CL and protein binding were determined and regressed against age and other covariates. In an ex vivo study, warfarin was spiked to plasma samples from 60 healthy subjects (19–87 years) and protein binding was regressed against age and other covariates.

RESULTS For (R)‐warfarin a significant decrease with age was found for both total and free CL (P < 0.001). For (S)‐warfarin there was a stronger signal of a decrease with age in free CL (P= 0.005) vs. total CL (P= 0.045). The decrease in CL of (R)‐ and (S)‐warfarin was 0.3–0.5% per year. Other covariates influencing CL were lean body weight for both (R)‐ and (S)‐warfarin and CYP2C9 genotype and blood sampling time for (S)‐warfarin. Protein binding of (R)‐ and (S)‐warfarin was not found to change significantly with age in either the clinical or the spiked samples, despite a slight decrease in albumin concentration with age.

CONCLUSIONS These data support the hypothesis that the CL of (R)‐ and (S)‐warfarin decreases with age. More accurate information was gained when measuring free CL for (S)‐warfarin. Warfarin protein binding did not change significantly with age.
The effect of dicyandiamide on pasture nitrate concentration, yield and N offtake under high N loading in winter and spring
Authors: Moir J. L. , Malcolm B. J. , Cameron K. C. , Di H. J.
Published: March 2012

High nitrate () concentrations in pastures and forages represent a health risk to grazing livestock. A field trial was conducted on the Lincoln University Dairy Farm, New Zealand, to investigate the effects of applying the nitrification inhibitor dicyandiamide (DCD) on soil extractable N and pasture concentrations in winter and spring. Treatments were control (T1), urea (T2), urea + DCD (T3), May urine + DCD (T4), August urine + DCD (T5), May urine (T6) and August urine (T7). Urine treatments were applied to the ryegrass‐white clover pasture in either May or August. The DCD treatments were applied at 10 kg DCD ha−1 in May and August and urea at 25 kg N ha−1 at selected intervals. Soil samples (0‐ to 75‐ and 75‐ to 150‐mm horizons) were taken regularly to monitor soil and ammonium () levels. Six pasture harvests were conducted from August 2007 to March 2008 and samples analysed for ‐N concentrations and total N content. Application of DCD significantly (P < 0·001) increased total dry‐matter (DM) production by 39 and 42% for the autumn and spring urine treatments, respectively, compared to the urine‐alone treatments. In addition, the application of DCD also significantly (P < 0·001) increased DM yield by 12% on the urea‐only treatment. DCD significantly (P < 0·001) reduced pasture concentrations in both autumn‐ and spring‐applied urine treatments where DCD was applied. This was directly linked to reductions in soil , and increases in soil , from DCD application. The preferential uptake by pasture for ‐N over ‐N may also have been a contributing factor. DCD application can therefore substantially reduce pasture ‐N concentrations to safe levels under high N‐loading (urine patch) conditions.
A study of clinico‐pathological parameters and O6 – methylguanine DNA methyltransferase (MGMT) promoter methylation status in the prognostication of gliosarcoma
Authors: Singh Geetika , Mallick Supriyo , Sharma Vikas , Joshi Nikhil , Purkait Suvendu , Jha Prerana , Sharma Mehar Chand , Suri Vaishali , Julka Pramod Kumar , Mahapatra Ashok Kumar , Singh Manmohan , Kale Shashank Sharad , Sarkar Chitra
Published: March 2012

Gliosarcoma is a rare variant of glioblastoma multiforme (GBM) with similar clinical presentation and prognosis but a distinct genetic profile. The clinicopathological features of 22 cases of gliosarcoma were analyzed with respect to age, sex, KPS score, operative diagnosis, extent of resection and histopathological subtype (predominantly sarcomatous [PS], predominantly gliomatous [PG] or mixed). Twelve cases were PS, six were PG and four were mixed. The histological subtype did not correlate with the operative diagnosis; however, it did significantly correlate with the extent of resection (P = 0.014). In 14 cases with available survival data it was found that none of the clinicopathological parameters significantly correlated with survival (P > 0.05). Methyl guanine DNA methyl transferase promoter methylation studies were performed using methylation‐specific PCR in 16 cases which showed a methylation rate of 31.25% (5/16). The promoter methylation status did not correlate with the histological subtype and did not significantly affect survival (P > 0.05). Although gliosarcomas continue to be treated in the same way as GBM, the role of chemotherapy with temozolomide is not clear. This cohort is the largest to date to uniformly receive the Stupp's protocol which is currently “standard of care” for GBM. A median overall survival of 18.5 months is substantially higher than previous studies, suggesting that temozolomide should be included in gliosarcoma therapy.
Functional morphology of the mandibular gland of queens of the ant Monomorium pharaonis (L.)
Authors: Boonen Sofie , Eelen Dieter , Børgesen Lisbeth , Billen Johan
Published: March 2012

In this study, the functional morphology of the mandibular glands of pharaoh ant queens is investigated through histological and behavioural observations. The mandibular glands of queens of different age stages and mating status were examined at the light microscopical as well as the ultrastructural level. The results clearly show a high activity of the gland at the time of hatching, followed by a rapid degeneration independent of the queens' mating status. We therefore hypothesize the glandular secretion serves to stimulate workers to remove the queens' pupal skin. Experiments to compare hatching ability of isolated pupae and pupae assisted by workers confirmed the necessity of worker assistance, which is even more crucial to allow proper wing formation in queens and males. Together with the histological data, this suggests that the mandibular gland may indeed play a role in the social facilitation of hatching, although bioassays are required to give decisive answers about the mandibular gland's function.
Putting twitter to the test: Assessing outcomes for student collaboration, engagement and success
Authors: Junco Reynol , Elavsky C. Michael , Heiberger Greg
Published: March 2012

Herein, we present data from two studies of Twitter usage in different postsecondary courses with the goal of analyzing the relationships surrounding student engagement and collaboration as they intersect learning outcomes. Study 1 was conducted with 125 students taking a first‐year seminar course, half of who were required to use Twitter while the other half used Ning. Study 2 was conducted with 135 students taking a large lecture general education course where Twitter participation was voluntary. Faculty in Study 1 engaged with students on Twitter in activities based on an a priori theoretical model, while faculty in Study 2 only engaged students sporadically on the platform. Qualitative analyses of tweets and quantitative outcomes show that faculty participation on the platform, integration of Twitter into the course based on a theoretically driven pedagogical model and requiring students to use Twitter are essential components of improved outcomes.

Practitioner notes

What is already known about this topic

Student use of social media is integrally related to how students engage the world.

Little research exists on how social media use is linked to college student engagement in relation to academic outcomes.

One study using a controlled design demonstrated a relationship between Twitter use and student engagement.

What this paper adds

An empirical comparison of two ways in which Twitter was differently integrated into college courses.

The utilization of quantitative and qualitative data to assess real‐world academic outcomes related to Twitter use.

Evidence‐based best practices for using Twitter in educationally relevant and productive ways.

Implications for practice and/or policy

If integrating Twitter in their courses, faculty should require and structure its use along educationally relevant criteria.

To achieve the most effective results, faculty should have a theoretically driven pedagogical basis for incorporating Twitter.

Faculty should actively engage with students on the platform to obtain maximum benefit.
Integrity—Clarifying and Upgrading an Important Concept for Business Ethics
Authors: TULLBERG JAN
Published: March 2012

This article discusses the concept of integrity. Often, integrity is used as a characteristic of individuals showing a high fidelity to generally praised norms. Here, a more independent meaning is suggested so that the concept implies a clear distance to integration instead of mixing up the two concepts. Integrity implies integration within the individual of beliefs, statements, and action. To what degree can society and companies accommodate a pluralism created by individuals with integrity? Here, it is argued that integrity is a useful virtue and that a more integrity‐friendly environment in companies would be beneficial by stimulating the empowered employee to make improved contributions. The concept is central for business ethics and crucial for the company's choice of such policies. A priority of integrity also affects organizational theory and the practical organizing of the company. Integrity is also vital for society at large for both citizens and companies, providing an ideological support for pluralism and a check on demands for conformism. The article also discusses how a virtue such as integrity can function as guidance for the individual operating in a complex world.
A Tale of Two Debtors: Responding to the Shock of Over‐Indebtedness in France and England – a Story from the Trente Piteuses
Authors: Ramsay Iain
Published: March 2012

England and France have developed distinct treatment systems to address the shock of a substantial increase in over‐indebted individuals since the mid‐1980s. In France, Over‐Indebtedness Commissions, with the Bank of France playing a central role in their management, now dominate the system. A more fragmented system of private and public providers of remedies developed in England, with innovation driven by private actors modifying existing commercial procedures and increased access to bankruptcy relief a side‐effect of government promotion of entrepreneurialism. This article explains the differences between these countries in terms of the influence of interest groups, including state actors, and ideologies. Historical contingency also plays a role. The distinct responses were not hard‐wired to legal origins and the article argues that analysis of the interaction of interest groups, state actors and ideology in shaping institutions, which in turn structure future change, provides a productive approach for future comparative research in this area.
Internal Restructuring and Firm Survival
Authors: Powell Ronan , Yawson Alfred
Published: March 2012

We examine the impact of two common methods of internal restructuring, layoffs and divestitures on the survival of a sample of UK firms. Using a Poisson regression model, we find that divestitures improve survival likelihood by reducing the probability and speed of market exit via takeover or bankruptcy, whereas layoffs increase the probability and speed of market exit via bankruptcy. Surprisingly, classifying firms into financially distressed and healthy groups, we find that distressed firms are less likely to restructure. Furthermore, while divestitures improve survival likelihood in both groups, layoff firms are less likely to survive, irrespective of whether they are distressed or healthy. Our findings are consistent with event studies that examine the market reaction to layoffs and divestiture decisions, and so provide some support for the view that the market correctly values the consequences of these restructuring actions on firm survival. The results are robust to several econometric and modeling issues, including controlling for potential self‐selection bias.
Cystatin C is a strong predictor of survival in patients with cirrhosis: is a cystatin C‐based MELD better?
Authors: Finkenstedt Armin , Dorn Livia , Edlinger Michael , Prokop Wolfgang , Risch Lorenz , Griesmacher Andrea , Graziadei Ivo , Vogel Wolfgang , Zoller Heinz
Published: March 2012

Background/Aims

The model of end stage liver disease (MELD) includes serum creatinine, which is a poor surrogate marker of renal function in patients with cirrhosis. Especially in women and patients with advanced disease creatinine underestimates true renal function. Our objective was to assess whether or not the substitution of creatinine by cystatin C improves the prognostic performance of the model.

Methods

The association between MELD parameters and cystatin C with survival was investigated using a Cox proportional hazards model. A cystatin C‐based MELD score was calculated from the results and compared with creatinine‐based MELD in terms of discrimination and calibration.

Results

Four hundred and twenty‐nine patients were included in the study; 19% died and 12% underwent liver transplantation during a median follow‐up of 602 days. In multivariate Cox regression, cystatin C was an independent predictor of 90‐day mortality with a hazard ratio of 8.0 (95% CI: 2.2–29.6). The median cystatin C‐based MELD was 15, the median creatinine‐based MELD was 12. Calibration and discrimination for 3 month and 1 year mortality was similar between the scores (AUC > 0.85 for both scores). Gender differences in cystatin C‐based MELD were less pronounced than those in the creatinine‐based model, because creatinine but not cystatin C was affected by gender.

Conclusion

Substitution of creatinine by cystatin C does not improve the predictive power of MELD.
A robust feldspar luminescence dating method for Middle and LatePleistocene sediments
Authors: Buylaert Jan‐Pieter , Jain Mayank , Murray Andrew S. , Thomsen Kristina J. , Thiel Christine , Sohbati Reza
Published: March 2012

Luminescence dating is used extensively to provide absolute chronologies for LatePleistocene sediments. Nowadays, most optical dates are based on quartz optically stimulated luminescence (OSL). However, the application of this signal is usually limited to the last ∼100 ka because of saturation of the quartz luminescence signal with dose. In contrast, the feldspar infrared stimulated luminescence (IRSL) dose–response curve grows to much higher doses; this has the potential to extend the datable age range by a factor of 4–5 compared with quartzOSL. However, it has been known for several decades that thisIRSLsignal is unstable, and this instability often gives rise to significant age underestimation. Here we test against independent age control the recently developed feldspar post‐IR IRSLapproach to the dating of sediments, which appears to avoid signal instability. A physical model explaining our observations is discussed, and the method is shown to be accurate back to 600 ka. The post‐IR IRSLsignal is reduced by exposure to daylight more slowly than that from quartz and low‐temperatureIRSL, preventing its general application to young (e.g.Holocene) sediments. Nevertheless, this new approach is widely applicable (feldspar of appropriate luminescence behaviour is even more ubiquitous than quartz). These characteristics make this a method of great importance for the dating of Middle and LatePleistocene deposits.
Role of cytokines in lavage or drainage fluid after hemithyroidectomy in wound healing: Involvement of histamine in the acceleration and delay of wound healing
Authors: Arai Miku , Ogita‐Nakanishi Hiromi , Lee Koutetsu , Yoshimura Katsuhiro , Kawata Ryo , Kanazawa Atsuko , Terada Tetsuya , Takenaka Hiroshi , Sato Tadasu , Endo Yasuo , Kato Ryuji , Ijiri Yoshio , Tanaka Kazuhiko , Tashiro‐Yamaji Junko , Kubota Takahiro , Yoshida Ryotaro
Published: March 2012

Wound healing is a sophisticated biologic process. In the case of hemithyroidectomy, the operation time is relatively short with small tissue damage and without skin excision, and bacterial contamination before, during, and after the operation is uncommon. Here, we explored which cytokine(s) affected the rates of healing of skin wounds after hemithyroidectomy of 29 patients. We assessed the amounts of cytokines (e.g., interleukin‐6, platelet‐derived growth factor, basic fibroblast growth factor, vascular endothelial growth factor, and tumor necrosis factor‐α) in either the preoperative or postoperative lavage fluids, or in the drainage fluids on postoperative days (PODs) 1–8. All of these cytokines showed a similar pattern; after reaching a peak on POD1, the production fell sharply on POD2–8, revealing that wound healing commenced on POD1. The rates of wound healing were inversely related to the levels of histamine in six patients (i.e., those with the three largest and those with the three smallest total volumes of drainage fluid on POD1): high (or low) levels of histamine in the postoperative lavage fluids with low (or high) levels in the drainage fluids on POD1 caused earlier (or the delay of) wound healing, suggesting involvement of histamine in the acceleration and delay of wound healing.
Green light emitting diodes accelerate wound healing: Characterization of the effect and its molecular basis in vitro and in vivo
Authors: Fushimi Tomohiro , Inui Shigeki , Nakajima Takeshi , Ogasawara Masahiro , Hosokawa Ko , Itami Satoshi
Published: March 2012

Because light‐emitting diodes (LEDs) are low‐coherent, quasimonochromatic, and nonthermal, they are an alternative for low level laser therapy, and have photobiostimulative effects on tissue repair. However, the molecular mechanism(s) are unclear, and potential effects of blue and/or green LEDs on wound healing are still unknown. Here, we investigated the effects of red (638 nm), blue (456 nm), and green (518 nm) LEDs on wound healing. In an in vivo study, wound sizes in the skin of ob/ob mice were significantly decreased on day 7 following exposure to green LEDs, and complete reepithelialization was accelerated by red and green LEDs compared with the control mice. To better understand the molecular mechanism(s) involved, we investigated the effects of LEDs on human fibroblasts in vitro by measuring mRNA and protein levels of cytokines secreted by fibroblasts during the process of wound healing and on the migration of HaCat keratinocytes. The results suggest that some cytokines are significantly increased by exposure to LEDs, especially leptin, IL‐8, and VEGF, but only by green LEDs. The migration of HaCat keratinocytes was significantly promoted by red or green LEDs. In conclusion, we demonstrate that green LEDs promote wound healing by inducing migratory and proliferative mediators, which suggests that not only red LEDs but also green LEDs can be a new powerful therapeutic strategy for wound healing.
Treatment of EARLY‐ONSET Gorham Syndrome with 8‐Year Follow‐Up
Authors: Maruani Annabel , Thimon Sylvie , de Courtivron Benoît , de Pinieux Gonzague , Baulieu Françoise , Machet Laurent , Lorette Gérard
Published: March 2012

Abstract:  A case of Gorham disease with several years of follow‐up is reported. At birth he had a mass in the thigh which was had pathology demonstrating a lymphangioma. By age 3 years, he had lymphedema of the ipsilateral foot and discrepant leg lengths. Radiography revealed heterogenous dystrophy of the bones and osteolysis of the hallux. At age 6, a spontaneous fracture of the right tibia was treated with surgery. Histopathology of a bone sample demonstrated bone remodelling, fibrous tissue, and large vascular lacunas within bone tissue, bordered by cells expressing the lymphaticmarker D2–40. At 8 years old, lymphedema of the right inferior leg had increased, leg lengths still differed, but other clinical signs were absent.