bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of interdiffusion around miscibility gap of lattice matched InGaAs∕InP quantum wells by high resolution x-ray diffraction
Authors: Bollet F. , Gillin W. P.
Published: January 2007

A methodology to characterize of thermally interdiffused heterostructures by high resolution x-ray diffraction is presented. The technique provides detailed information on the strains and compositions generated throughout the interdiffusion process in a 10nm lattice matched InGaAs∕InP sample annealed at 800°C. It shows that the diffusion process is complex and subject to the influence of the miscibility gap in the quaternary InGaAsP system. The technique also appears to provide a route to mapping the binodal isotherms of the InGaAsP miscibility gap.
Sound beyond the speed of light: Measurement of negative group velocity in an acoustic loop filter
Authors: Robertson W. M. , Pappafotis J. , Flannigan P. , Cathey J. , Cathey B. , Klaus C.
Published: January 2007

The authors describe the experimental observation of negative group velocity propagation of sound waves through an asymmetric loop filter. The characteristics of the filter are established using impulse response and direct tunneling of narrow bandwidth Gaussian pulses. The results confirm recent theoretical predictions that faster-than-light group velocity propagation of sound is possible. Further, the results show that the spectral rephasing achieved in a loop filter is sufficient to produce negative group velocities independent of the phase velocity of the spectral components themselves. Thus, superluminal propagation is realized despite almost six orders of magnitude difference between the speeds of sound and light.
Nanoillumination based on self-focus and field enhancement inside a subwavelength metallic structure
Authors: Liu Cheng , Chen Nanguang , Sheppard Colin
Published: January 2007

A subwavelength metallic structure is proposed to generate superstrong nanoillumination. Its attractive features are presented numerically with finite-difference time-domain method. By combining a subwavelength slit and a nanohole together into metallic screen, the light illuminated on the surface of the screen is firstly squeezed into the subwavelength slit with the aid of the generated surface plasmon, and then during propagation to the exit end of the slit, the light is focused on a nanohole fabricated at the bottom of the slit due to the self-imaging effect and is further enhanced by the transmission resonance when passing through the nanohole. Because of these three successive enhancement processes, the light from the nanohole could become thousand times stronger than the incident light and accordingly could have great potentials for applications in optical data storage, super-resolution imaging, lithography, photonics, and other applications that need nanoillumination.
Imaging of closed cracks using nonlinear response of elastic waves at subharmonic frequency
Authors: Ohara Yoshikazu , Mihara Tsuyoshi , Sasaki Ryouta , Ogata Toshihiro , Yamamoto Setsu , Kishimoto Yuuki , Yamanaka Kazushi
Published: January 2007

The authors constructed a novel apparatus based on subharmonic ultrasound for the accurate imaging of closed cracks. Linear and nonlinear responses not only from the tip but also from other parts of cracks were observed in fundamental and subharmonic images, which were changed with varying closure stress. The subharmonic images always gave an accurate length of partially closed cracks, in contrast to the fundamental images in which the crack length was underestimated. Significant similarities in generation and resonance phenomena of subharmonic waves, acoustic emission, and the vibration of microbubbles are discussed.
General analytical Poisson solution for undoped generic two-gated metal-oxide-semiconductor field-effect transistors
Authors: Shangguan W. Z. , Au Yeung T. C. , Zhu Z. M. , Zhou X.
Published: January 2007

We present a general analytical solution to the Poisson equation for undoped semi-conductors. This general Poisson solution is then applied to generic dual-gate metal-oxide- semiconductor field-effect transistors (MOSFETs), unifying different types including silicon-on-insulator, and symmetric and asymmetric double-gate MOSFETs. Newton-Raphson (NR) algorithm is called to solve the resulting surface-potential equation. An exact solution is proposed making the NR algorithm computationally very efficient. While the universal initial guess can be used as an approximate solution for fast evaluation, the iterative results by NR algorithm are useful for benchmark tests.
Adipocyte Enhancer-binding Protein-1 Promotes Macrophage Inflammatory Responsiveness by Up-Regulating NF-κB via IκBα Negative Regulation
Authors: Majdalawieh Amin , Zhang Lei , Ro Hyo-Sung
Published: January 2007

Nuclear factor κB (NF-κB) subunits comprise a family of eukaryotic transcription factors that are critically involved in cell proliferation, inflammation, and apoptosis. Under basal conditions, NF-κB subunits are kept under inhibitory regulation by physical interaction with NF-κB inhibitors (IκB subunits) in the cytosol. Upon stimulation, IκB subunits become phosphorylated, ubiquitinated, and subsequently degraded, allowing NF-κB subunits to translocate to the nucleus and bind as dimers to κB responsive elements of target genes. Previously, we have shown that AEBP1 enhances macrophage inflammatory responsiveness by inducing the expression of various proinflammatory mediators. Herein, we provide evidence suggesting that AEBP1 manifests its proinflammatory function by up-regulating NF-κB activity via hampering IκBα, but not IκBβ, inhibitory function through protein–protein interaction mediated by the discoidin-like domain (DLD) of AEBP1. Such interaction renders IκBα susceptible to enhanced phosphorylation and degradation, subsequently leading to augmented NF-κB activity. Collectively, we propose a novel molecular mechanism whereby NF-κB activity is modulated by means of protein–protein interaction involving AEBP1 and IκBα. Moreover, our study provides a plausible mechanism explaining the differential regulatory functions exhibited by IκBα and IκBβ in various cell types. We speculate that AEBP1 may serve as a potential therapeutic target for the treatment of various chronic inflammatory diseases and cancer.
An interleukin-4-dependent precursor clone is an intermediate of the differentiation pathway from an interleukin-3-dependent precursor clone into myeloid cells as well as B lymphocytes
Authors: Kinashi Tatsuo , Tashiro Kel , Inaba Kayo , Takeda Toshio , Palacios Ronald , Honjo Tasuku
Published: January 2007

An Interleukin-3-dependent progenitor clone LyD9 and its Interleukin-4-dependent derivative clone K-4 were shown to differentiate into myeloid cells as well as B lymphocytes by coculture with bone marrow stroma cells. The K-4 clone is an Intermediate between myeloid/lymphoid cells and the LyD9 clone that requires Interleukin-4 for differentiation into B lymphocytes and myeloid cells. Granulocyte-macrophage colony stimulating factor-dependent derivatives (LS-1 and KGM) were also established from Induced LyD9 cells. LS-1 and K-GM were myeloid-committed cells.
High Prevalence of α‐1‐Antitrypsin Heterozygosity in Children With Chronic Liver Disease
Authors: Campbell Kathleen M , Arya Gajra , Ryckman Frederick C , Alonso Maria , Tiao Greg , Balistreri William F , Bezerra Jorge A
Published: January 2007

Objective:

α‐1‐antitrypsin (A1AT) deficiency is the most common genetic cause of liver disease in children; however, the role of polymorphic heterogeneity in the A1AT gene as a modifier of other forms of pediatric liver disease is not clear. We hypothesized that non‐M A1AT allele variants are more common in children with chronic liver disease than in the general population.

Methods:

A retrospective, single‐center study was performed in which A1AT phenotypes were obtained by reviewing charts of children with chronic liver disease. Chi‐square analysis was used to compare allele frequencies in the population of children with liver disease with published epidemiologic data and to compare allele frequencies among disease subgroups.

Results:

The frequency of A1AT Z and other alleles was increased in children with chronic liver disease (n = 241) when compared with the published reference database (P < 0.001). This increase remained significant when the population was divided into disease subsets: biliary atresia (n = 67) and other liver disease (n = 174) (P < 0.001 for both). Among children with biliary atresia referred for liver transplant evaluation, the presence of a non‐M allele was associated with a lower mean age at transplant listing than the MM phenotype (235 vs 779 days, P = 0.036) and more frequent loss of native liver by 24 months of age (90% vs 65%, P = 0.04).

Conclusions:

A1AT non‐M alleles are more frequent in children with chronic liver disease than in the general population. We speculate that these non‐M alleles may act as genetic modifiers in pediatric liver disease in general and modulate disease progression in children with biliary atresia in particular.
Effect of Omeprazole on Acid Gastroesophageal Reflux and Gastric Acidity in Preterm Infants With Pathological Acid Reflux
Authors: Omari Taher I , Haslam Ross R , Lundborg Per , Davidson Geoffrey P
Published: January 2007

Introduction:

Proton pump inhibitor (PPI) therapy is increasingly being used to treat premature infants with gastroesophageal reflux disease (GERD); however, the efficacy of PPI on acid production in this population has yet to be assessed in this patient group. The aim of this study was to determine the effect of 0.7 mg/kg/d omeprazole on gastric acidity and acid gastroesophageal reflux in preterm infants with reflux symptoms and pathological acid reflux on 24‐h pH probe.

Methods:

A randomized, double blind, placebo‐controlled, crossover design trial of omeprazole therapy was performed in 10 preterm infants (34–40 weeks postmenstrual age). Infants were given omeprazole for 7 d and then placebo for 7 d in randomized order. Twenty‐four‐hour esophageal and gastric pH monitoring was performed on days 7 and 14 of the trial.

Results:

Compared to placebo, omeprazole therapy significantly reduced gastric acidity (%time pH <4, 54% vs 14%, P < 0.0005), esophageal acid exposure (%time pH <4, 19% vs 5%, P < 0.01) and number of acid GER episodes (119 vs 60 episodes, P < 0.05).

Conclusions:

Omeprazole is effective in reducing esophageal acid exposure in premature infants with pathological acid reflux on 24‐h pH probe; however, the far more complex issues of safety and efficacy have yet to be addressed.
Reversal of tacrolimus‐related hypertrophic cardiomyopathy after conversion to rapamycin in a pediatric liver transplant recipient
Authors: Turska‐Kmieć Anna , Jankowska Irena , Pawłowska Joanna , Kaliciński Piotr , Kawalec Wanda , Tomyn Małgorzata , Markiewicz Małgorzata , Teisseyre Joanna , Czubkowski Piotr , Rękawek Joanna , Socha Jerzy
Published: January 2007

Abstract:  Tacrolimus (Tac)‐related hypertrophic cardiomyopathy (HCM) has been reported to be an unusual but serious complication affecting pediatric patients after solid organ transplantation. Herein, we present a case of young liver transplant recipient with Tac‐induced HCM, treated by discontinuation of Tac followed by conversion to rapamycin (Rap). Our case report points out the potential but rather low risk of HCM during Tac immunosuppression in pediatric liver transplants and demonstrates that replacement of calcineurin inhibitors with mammalian target of Rap (mTOR) inhibitors may be an efficacious therapeutic tool to effect regression of established cardiac hypertrophy.
Assessment of Sperm Apoptosis in Cryopreserved Bull Semen After Swim‐up Treatment: A Flow Cytometric Study
Authors: Chaveiro A , Santos P. , Da Silva FM
Published: January 2007

Contents

The techniques used to prepare bovine spermatozoa forin vitrofertilization, to enhance the percentage of motile sperm cells include the swim‐up (SU) method, among others. The objective of the present study was to evaluate the phosphatidylserine (PS) translocation and plasma membrane integrity as the indicator of apoptosis and necrosis in post‐thaw bull sperm after SU treatment using annexin V‐fluorescein isothiocyanate (FITC)/propidium iodide (PI) assay. A flow cytometric method was employed to measure apoptosis levels on frozen‐thawed bull spermatozoa. The assay detects PS translocation across the plasma membrane using a fluorescein‐labelled annexin‐V and PI. By using the annexin V/PI assay four different subpopulations of sperm were observed: (i) a population of apoptotic sperm, labelled with annexin V–FITC but not with PI; (ii) a population of early necrotic spermatozoa, sperm labelled with annexin–FITC and PI; (iii) a population of necrotic sperm, labelled with PI but not with annexin–FITC; and (iv) a population of fully viable sperm cells, sperm not labelled with annexin V–FITC and without PI. Results clearly indicated that SU technique itself could have an adverse effect on the spermatozoa membrane stability. It has also been found, significant differences between bulls in the levels of apoptotic sperm, after SU treatment.
Unusual haematologic manifestations of Mycoplasma pneumoniae infection
Authors: Kottayam Radhakrishnan , Rozenberg Gillian , Cohn Richard J
Published: January 2007

Abstract:  A 2‐year‐old male presented with fever, cervical lymphadenopathy, anaemia, neutrophilia and thrombocytosis. There was no evidence of pulmonary disease. Severe cold antibody (IgM) mediated haemolytic anaemia developed during admission. Infection with Mycoplasma pneumoniae was demonstrated, highlighting the extrapulmonary manifestations of the infection, in the absence of pulmonary signs.
Teaching and Learning Ontology and Epistemology in Political Science
Authors: Bates Stephen R. , Jenkins Laura
Published: January 2007

The teaching and learning of ontology and epistemology is an important element of political science, as it helps students to appraise, differentiate and choose between competing philosophies, theories and analytical traditions. Thus, it encourages reflexive learning through the strategies of inquiry, role taking and benign disruption. However, we argue that there are aspects within the most prominent introductory material on these meta-theoretical issues which may undermine these processes. In particular, definitional inaccuracies and a lack of sustained reflection on the contested nature of the directional relationship between ontology and epistemology tend towards a prescriptive ‘path dependency’ and curtail the possibility of reflexive learning. By subjecting this received knowledge to critical reflection, we hope to overturn these weaknesses and open up a debate on the teaching and learning of ontology and epistemology.
NGF augments the autophosphorylation of Ret via inhibition of ubiquitin‐dependent degradation
Authors: Pierchala Brian A. , Tsui Cynthia C. , Milbrandt Jeffrey , Johnson Eugene M.
Published: January 2007

Nerve growth factor (NGF) is required for the trophic maintenance of postnatal sympathetic neurons. A significant portion of the growth‐promoting activity of NGF is from NGF‐dependent phosphorylation of the heterologous receptor tyrosine kinase, Ret. We found that NGF applied selectively to distal axons of sympathetic neurons maintained in compartmentalized cultures activated Ret located in these distal axons. Inhibition of either proteasomal or lysosomal degradation pathways mimicked the effect of NGF on Ret activation. Likewise, NGF inhibited the degradation of Ret induced by glial cell line‐derived neurotrophic factor‐dependent activation, a process that requires ubiquitination and proteasomal degradation. NGF induced the accumulation of autophosphorylated Ret predominantly in the plasma membrane, in contrast to GDNF, which promoted the internalization of activated Ret. An accretion of monoubiquitinated, but not polyubiquitinated, Ret occurred in NGF‐treated neurons, in contrast to glial cell line‐derived neurotrophic factor that promoted the robust polyubiquitination of Ret. Thus, NGF stimulates Ret activity in mature sympathetic neurons by inhibiting the ongoing ubiquitin‐mediated degradation of Ret before its internalization and polyubiquitination.
Effects of Cash and Counseling on Personal Care and Well‐Being
Authors: Carlson Barbara Lepidus , Foster Leslie , Dale Stacy B. , Brown Randall
Published: January 2007

Objective. To examine how a new model of consumer‐directed care changes the way that consumers with disabilities meet their personal care needs and, in turn, affects their well‐being.

Study Setting. Eligible Medicaid beneficiaries in Arkansas, Florida, and New Jersey volunteered to participate in the demonstration and were randomly assigned to receive an allowance and direct their own Medicaid supportive services as Cash and Counseling consumers (the treatment group) or to rely on Medicaid services as usual (the control group). The demonstration included elderly and nonelderly adults in all three states and children in Florida.

Data Sources. Telephone interviews administered 9 months after random assignment.

Methods. Outcomes for the treatment and control group were compared, using regression analysis to control for consumers' baseline characteristics.

Principal Findings. Treatment group members were more likely to receive paid care, had greater satisfaction with their care, and had fewer unmet needs than control group members in nearly every state and age group. However, among the elderly in Florida, Cash and Counseling had little effect on these outcomes because so few treatment group members actually received the allowance. Within each state and age group, consumers were not more susceptible to adverse health outcomes or injuries under Cash and Counseling.

Conclusions. Cash and Counseling substantially improves the lives of Medicaid beneficiaries of all ages if consumers actually receive the allowance that the program offers.
Case Histories of Six Consumers and Their Families in Cash and Counseling
Authors: San Antonio Patricia M. , Simon‐Rusinowitz Lori , Loughlin Dawn , Eckert J. Kevin , Mahoney Kevin J.
Published: January 2007

Objective. To examine how the lives of consumers and their caregivers were affected by making choices and controlling their own resources with the cash option, this paper focuses on six case studies from the Cash and Counseling Demonstration Program.

Data Sources. Twenty‐one consumers, caregivers, and state consultants were interviewed about their experiences in the program.

Study Design. The data come from a larger study of over 200 interviews conducted from June 2000 to August 2004. Interview data were analyzed for themes about caregiving and program satisfaction.

Principal Findings. Cash and Counseling benefited consumers and caregivers by allowing consumers increased continuity and reliability of care, increased ability to set hours of care, more satisfaction with how caregiving is offered and more satisfaction with the quality of care.

Conclusions. The cash option allowed consumers to create, schedule, and manage their own model of care. Some consumers faced challenges in the program with paperwork, accounting, worries about receiving care, and some ineffective state consultants who could have been more helpful.
Human Prolactin Promotes Human Secondary Immunoglobulin Response in Human/SCID Mouse Chimeras
Authors: Zhang Jian , Sun Rui , Tian Zhigang
Published: January 2007

Recombinant human prolactin (rhPRL) was administered to huPBL-SCID mice to determine its effects on production of human immunoglobulin (Ig). The huPBL-SCID mice were injected intraperitoneally (i.p.) with 10 μg rhPRL every other day for a total of 10 injections. The results reconfirmed that rhPRL significantly increased the numbers of human CD3+T cells and human CD19+B cells in spleens, lymph nodes, and thymuses of huPBL-SCID mice. The huPBL-SCID mice were then concurrently given various doses of diphtheria-tetanus (DT) vaccine and 10-μg i.p. injections of rhPRL and were examined for the presence of human DT-specific proliferation of lymph node cells in vitro and antibody production in vivo. rhPRL greatly improved the engraftment of functional human lymphocytes (CD3+T cells and CD19+B cells) in DT-immunized huPBL-SCID mice. The rhPRL-treated, DT-immunized huPBL-SCID mice produced significantly larger amounts of DT-specific antibodies in response to the vaccine. The predominant Ig isotype induced after immunization was IgG. Thus, rhPRL stimulation promotes human secondary IgG responses in huPBL-SCID mice.
Comparative Evaluation of Etest and Sensititre YeastOne Panels against the Clinical and Laboratory Standards Institute M27-A2 Reference Broth Microdilution Method for Testing
Candida
Susceptibility to Seven Antifungal Agents
Authors: Alexander Barbara D. , Byrne Terry C. , Smith Kelly L. , Hanson Kimberly E. , Anstrom Kevin J. , Perfect John R. , Reller L. Barth
Published: January 2007

To assess their utility for antifungal susceptibility testing in our clinical laboratory, the Etest and Sensititre methods were compared with the Clinical and Laboratory Standards Institute (CLSI) M27-A2 reference broth microdilution method. Fluconazole (FL), itraconazole (I), voriconazole (V), posaconazole (P), flucytosine (FC), caspofungin (C), and amphotericin B (A) were tested with 212
Candida
isolates. Reference MICs were determined after 48 h of incubation, and Etest and Sensititre MICs were determined after 24 h and 48 h of incubation. Overall, excellent essential agreement (EA) between the reference and test methods was observed for Etest (95%) and Sensititre (91%). Etest showed an ≥92% EA for MICs for all drugs tested; Sensititre showed a ≥92% EA for MICs for I, FC, A, and C but 82% for FL and 85% for V. The overall categorical agreement (CA) was 90% for Etest and 88% for Sensititre; minor errors accounted for the majority of all categorical errors for both systems. Categorical agreement was lowest for
Candida glabrata
and
Candida tropicalis
with both test systems. Etest and Sensititre provided better CA at 24 h compared to 48 h for
C. glabrata
; however, CA for
C. glabrata
was <80% for FL with both test systems despite MIC determination at 24 h. Agreement between technologists for both methods was ≥98% for each agent against all organisms tested. Overall, Etest and Sensititre methods compared favorably with the CLSI reference method for determining the susceptibility of
Candida
. However, further evaluation of their performance for determining the MICs of azoles, particularly for
C. glabrata
, is warranted.
Multi-Party, Multi-Sector Knowledge Creation: Maximising Outcomes Through Stakeholder Collaboration
Authors: Rod Michel
Published: January 2007

This paper illustrates an example of successful collaboration amongst a number of organisations within the "Triple Helix" of government-industry-university relations whose mandate is to create, share and disseminate knowledge. A stakeholder perspective is used to identify a number of conditions that are suggested as being necessary for such complex collaborations to achieve their desired outcomes.
Studies of Shape Memory Property on Thermoplastic Segmented Polyurethanes: Influence of PEG 3400
Authors: Mondal S. , Hu J. L.
Published: January 2007

Thermomechanical and shape memory behavior on thermo plastic segmented polyurethane (SPU) copolymers based on polytetramethylene glycol (number average molecular weight, Mn = 2900 g mol 1), 1,4-butane diol, 4,4′-diphenylmethane diisocyanate (MDI), and with/without polyethylene glycol (PEG) (number average molecular weight, Mn = 3400 g mol-1) were studied. SPU with 5 wt% of PEG 3400 showed the highest tensile storage modulus at all temperatures due to the increased interaction between the polymer chains. On the other hand, SPU containing 15 wt% of PEG has a broad loss modulus (E″) due to increasing chain flexibility. The recovery process in shape memory behavior has been noticed to be the orientation of disoriented chains due to the thermodynamic entropy effect. Experimental studies revealed that the shape recovery properties are improved by increasing the percent crystallinity and/or physical cross-linking between the polymer chains. However, all SPU samples show excellent shape fixity.
Fiji, Iraq and Pacific island security
Authors: Maclellan Nic
Published: January 2007

The reverberations from the war in Iraq have been felt worldwide- and in regions far distant from the Middle East. A whole industry has grown up, in which private military and security corporations plug the gaps that the armed forces of the US and Britain cannot fill, providing back-up services, security and logistics. The Pacific nation of Fiji, with its highly regarded military tradition, has proved a fertile recruiting ground for such companies. High unemployment and lack of opportunity in Fiji has meant that Fijians are serving- and suffering casualties-in Iraq in increasing numbers. Moreover, this trend to outsourcing core national government functions of defence and security has boomeranged back on the Pacific nations themselves, potentially adding to destabilisation and insecurity in the region.
Contextual Empowerment: The Impact of Health Brigade Involvement on the Women of Miraflor, Nicaragua
Authors: Jewell Gayla
Published: January 2007

This qualitative, descriptive study investigated how working with Health Brigades influenced a sense of empowerment and a resultant shifting of gender-power relationships for women in a rural Nicaraguan community. A convenience sample of 10 women aged 18 to 65 years who had worked with the Brigades were interviewed. Open and axial coding were used to determine core categories and theoretical concepts. From this emerged a grounded theory of contextual empowerment. Key findings included that within this collectivist culture, the concept of contextual empowerment includes psychosocial and structural dimensions. Implications for nursing practice include the impact of unintentional role modeling.
A Linguistic “Asking, Promising, Asserting, and Declaring” Couples’ Communication Activity
Authors: Eckstein Daniel , Byles Torrey , Bennett Sherri
Published: January 2007

The article identifies and defines four basic “requesting, promising, asserting, and declaring” linguistic couples’ communication acts. A couple’s assessment and an application activity based on the four communication acts are presented as a method of improving relationships.
Depression, anxiety and stress among Saudi adolescent school boys
Authors: Al-Gelban Khalid S
Published: January 2007

Aims: This study reports on research to determine the prevalence rates and severity of depression, anxiety and stress among Saudi adolescent boys. A cross-sectional study, of secondary school boys at Abha, Aseer Region, Saudi Arabia was conducted.

Methods: The systematic sampling method was used to select a class at each level in a school. All the students were informed in detail about the study. The Arabic version of Depression, Anxiety and Stress Scale (DASS) was used to establish school-boy levels of depression, anxiety and stress.

Results: Results indicated that of 1723 male students recruited to this study, 59.4% had at least one of the three disorders, 40.7% had at least two and 22.6% had all the three disorders. Moreover, more than one third of the participants (38.2%) had depression, while 48.9% had anxiety and 35.5% had stress. Depression, anxiety and stress were strongly, positively, and significantly correlated.

Conclusion: It was concluded that there is an urgent need to pay more attention to the mental health of adolescent secondary school boys in Saudi Arabia. Further studies are needed to explore knowledge and attitude of students, parents and teachers concerning mental health.
Wnt11/β-catenin signaling in both oocytes and early embryos acts through LRP6-mediated regulation of axin
Authors: Kofron Matt , Birsoy Bilge , Houston Douglas , Tao Qinghua , Wylie Christopher , Heasman Janet
Published: January 2007

Current models of canonical Wnt signaling assume that a pathway is active if β-catenin becomes nuclearly localized and Wnt target genes are transcribed. We show that, in Xenopus, maternal LRP6 is essential in such a pathway, playing a pivotal role in causing expression of the organizer genes siamois and Xnr3, and in establishing the dorsal axis. We provide evidence that LRP6 acts by degrading axin protein during the early cleavage stage of development. In the full-grown oocyte, before maturation, we find that axin levels are also regulated by Wnt11 and LRP6. In the oocyte,Wnt11 and/or LRP6 regulates axin to maintain β-catenin at a low level,while in the embryo, asymmetrical Wnt11/LRP6 signaling stabilizesβ-catenin and enriches it on the dorsal side. This suggests that canonical Wnt signaling may not exist in simple off or on states, but may also include a third, steady-state, modality.
Foot and Mouth Disease Eradication in Former Czechoslovakia
Authors: Kouba V.
Published: January 2007

In former Czechoslovakia after the Second World War foot and mouth disease (FMD) was widely spread causing enormous losses to animal production. First reliable data were from 1952 when the FMD was reported in 5,912 villages with 316,997 diseased and 23,112 dead animals. Following a very demanding anti-FMD programme, panzootic occurrence was gradually reduced to sporadic cases and finally to the eradication in 1975. During 1952-1975 there were reported 8,898 new FMD outbreaks (villages). Anti-FMD protection measures, eradication strategy and methods are described. The eradication was achieved mainly thanks to strict measures for avoiding FMD introduction from abroad, animal population health protection including FMD vaccination of threatened populations (annual ratios vaccinations/cattle population oscillated between 0.0293 in 1955 and 1.8168 in 1973 with an average of 0.6445) and timely FMD discovery followed by a rapid response applying very strict intrafocal, perifocal and territorial measures. There were used different complex methods, including stamping-out, adjusted flexibly in time and place to epizootiological situation and influencing factors such as livestock concentration in large units. Important role was played by the strong and centralized public veterinary service with adequate infrastructure, necessary facilities such as FMD diagnostic laboratory, vaccine production and rendering plants, material and financial support. During 1957-1960, a particular epizootiological research was conducted in 70 districts, 245 villages and 459 farms affected by FMD; the results were expressed in morbidity, mortality, sanitary slaughter, disease course, outbreak duration, promptness of disease detection and response, virus types and ways of transmission.
Modeling of oxygen mass transfer in a gas–liquid airlift reactor
Authors: Talvy Samuel , Cockx Arnaud , Liné Alain
Published: January 2007

This article focuses on the physical modeling and numerical simulation of mass transfer in two‐phase bubbly flow in an airlift internal loop reactor. The objective of this article is to show the ability of computational fluid dynamics (CFD) to correctly simulate mass transfer in such a bubbly reactor. The modeling of two‐phase bubbly flow is based on the so‐called two‐fluid model derived from Reynolds‐averaged Navier–Stokes equations in two‐phase flow. From the hydrodynamic perspective, the flow is steady state. Given the steady‐state distributions of phases, interfacial area, and velocity field in the whole volume of the airlift, mass transfer is computed and the evolution of oxygen concentration in the two phases is predicted. Numerical simulations are discussed after comparison to experimental data. The simulations are validated in terms of oxygen concentration in the liquid vs. time. Then, different points are discussed, in particular, the perfectly mixed reactor assumption in the liquid phase and the spatial and temporal heterogeneity of oxygen concentration in the gas arising from oxygen impoverishment in bubbles in the downcomer. This leads to heterogeneity of the transfer driving force between the gas and the liquid. Bubble age or residence time in the airlift loop reactor has been calculated to show the weak renewal of oxygen in bubbles in the downcomer. This discussion generates questions on the estimation of a global mass transfer coefficient from experiments in such a heterogeneous airlift reactor. © 2007 American Institute of Chemical Engineers AIChE J 2007
Pulsed and continuous wave mobile phone exposure over left versus right hemisphere: Effects on human cognitive function
Authors: Haarala Christian , Takio Fiia , Rintee Taija , Laine Matti , Koivisto Mika , Revonsuo Antti , Hämäläinen Heikki
Published: January 2007

The possible effects of continuous wave (CW) and pulse modulated (PM) electromagnetic field (EMF) on human cognition was studied in 36 healthy male subjects. They performed cognitive tasks while exposed to CW, PM, and sham EMF. The subjects performed the same tasks twice during each session; once with left‐sided and once with right‐sided exposure. The EMF conditions were spread across three testing sessions, each session separated by 1 week. The exposed hemisphere, EMF condition, and test order were counterbalanced over all subjects. We employed a double‐blind design: both the subject and the experimenter were unaware of the EMF condition. The EMF was created with a signal generator connected via amplifier to a dummy phone antenna, creating a power output distribution similar to the original commercial mobile phone. The EMF had either a continuous power output of 0.25 W (CW) or pulsed power output with a mean of 0.25 W. An additional control group of 16 healthy male volunteers performed the same tasks without any exposure equipment to see if mere presence of the equipment could have affected the subjects' performance. No effects were found between the different EMF conditions, separate hemisphere exposures, or between the control and experimental group. In conclusion, the current results indicate that normal mobile phones have no discernible effect on human cognitive function as measured by behavioral tests. Bioelectromagnetics 28:289–295, 2007. © 2007 Wiley‐Liss, Inc.
Volsurf computational method applied to the prediction of stability of thermostable enzymes
Authors: Braiuca Paolo , Buthe Andreas , Ebert Cynthia , Linda Paolo , Gardossi Lucia
Published: January 2007

A computational model for the quantitative prediction of protein thermostability has been developed by means of the Volsurf method. A data set of 22 enzymes of reported thermostability in water systems, for the most part coming from thermophilic and hyperthermophilic organisms, has been built up. Molecular descriptors of the protein surface have been calculated and their role in the stabilization of the macromolecule has been analyzed by a multivariate statistical approach. The resulting regression model has shown a good predictivity and it has been able to quantitatively identify some structural requirements correlated with protein stability. The method can be the basis for a new computational support tool in rational protein design, which is complementary to the existing methods based on the sequence analysis.
Interruption of blood flow during compression and radial artery occlusion after transradial catheterization
Authors: Sanmartin Marcelo , Gomez Monica , Rumoroso Jose Ramon , Sadaba Mario , Martinez Maite , Baz Jose Antonio , Iniguez Andres
Published: January 2007

Objectives: To analyze the possible relationship between compression after transradial catheterization and radial artery occlusion. Background: Radial artery occlusion is an important concern of transradial catheterization. Interruption of radial artery flow during compression might influence the rate of radial artery occlusion at follow‐up. Methods: A prospective study including 275 consecutive patients undergoing transradial catheterization was conducted. Arterial sheaths were removed immediately after procedures and conventional compressive dressings were left in place for 2 hr. The pulse oximeter signal in the index finger during ipsilateral ulnar compression was used for the assessment of radial artery flow. Results: Radial artery flow was absent in 174 cases (62%) immediately after entry‐site compression. After 2 hr of conventional hemostasis, radial artery flow was absent in 162 cases (58%) before bandage removal. At 7‐day follow‐up, 12 patients (4.4%) had absent pulsations and radial artery flow was absent in 29 cases (10.5%). Patients with an occluded radial artery at follow‐up had significantly smaller arterial diameters at baseline (2.23 ± 0.4 mm vs. 2.40 ± 0.5 mm; P = 0.032) and more frequently had absent flow during hemostasis (90% vs. 54%, P < 0.001). Stepwise logistic regression analysis revealed that absent flow before compressive bandages removal was the only independent predictor of radial artery occlusion at follow‐up (OR = 6.7; IC 95%: 1.95‐22.9; P = 0.002). Conclusions: Flow‐limiting compression is a frequent finding during conventional hemostasis after transradial catheterization. Absence of radial artery flow during compression represents a strong predictor of radial artery occlusion. © 2007 Wiley‐Liss, Inc.
Identification of soluble CD14 as an endogenous agonist for Toll‐like receptor 2 on human astrocytes by genome‐scale functional screening of glial cell derived proteins
Authors: Bsibsi Malika , Bajramovic Jeffrey J. , Van Duijvenvoorden Eveline , Persoon Carla , Ravid Rivka , Van Noort Johannes M. , Vogt Mario H. J.
Published: January 2007

Human astrocytes express a limited repertoire of Toll‐like receptor (TLR) family members including TLR1‐4, which are expressed on the cell surface. Also, TLR3 but not TLR4 activation on astrocytes induces expression of several factors involved in neuroprotection and down‐regulation of inflammation rather than in the onset of traditional pro‐inflammatory reactions. The notion that astrocyte TLR may thus play a role not only in host defense but also in tissue repair responses prompted us to examine the possibility that endogenous TLR agonists could be expressed in the human central nervous system to regulate the apparently dual astrocyte functions during trauma or inflammation. As a potential source of endogenous agonists, a cDNA library derived from several human brain tumor cell lines was used. Gene pools of this library were transfected into COS‐7 cells and the expression products were screened for their ability to induce TLR activation in human primary astrocytes. The screening resulted in the identification of soluble CD14. By using a panel of TLR‐transfected HEK293 cells, we found that signaling by soluble CD14 was TLR2 dependent. Moreover, the CD14‐triggered TLR2‐mediated response in astrocytes lead to the production of CXCL8, IL‐6, and IL12p40, whereas typical TLR‐induced pro‐inflammatory cytokines, like TNF‐α and IL‐1β, were not produced at detectable levels. In conclusion, our data indicate that apart from its well‐known ability to act as a co‐receptor for TLR‐dependent signaling by peptidoglycans or LPS, soluble CD14 can also act as a direct agonist for TLR2. © 2007 Wiley‐Liss, Inc.
Coffee consumption and the risk of colorectal cancer: A prospective cohort study in Japan
Authors: Naganuma Toru , Kuriyama Shinichi , Akhter Munira , Kakizaki Masako , Nakaya Naoki , Matsuda‐Ohmori Kaori , Shimazu Taichi , Fukao Akira , Tsuji Ichiro
Published: January 2007

An inverse association between coffee consumption and the risk of colorectal cancer has been reported in several case–control studies, but results from prospective cohort studies have been inconclusive. We conducted a prospective cohort study among a Japanese population to clarify the association between coffee consumption and the risk of colorectal cancer incidence. We used data from the Miyagi Cohort Study for this analysis. Usable self‐administered questionnaires about coffee consumption were returned from 22,836 men and 24,769 women, aged 40–64 years, with no previous history of cancer. We used the Cox proportional‐hazard regression model to estimate hazard ratios and 95% confidence intervals. During 11.6 years of follow‐up (425,303 person‐years), we identified 457 cases of colorectal cancer. Coffee consumption was not associated with the incidence of colorectal, colon or rectal cancer. The multivariate‐adjusted hazard ratio (95% confidence interval) of colorectal cancer incidence for 3 or more cups of coffee per day as compared with no consumption was 0.95 (0.65–1.39) for men and women (p for trend = 0.55), 0.91 (0.56–1.46) for men (p for trend = 0.53) and 1.16 (0.60–2.23) for women (p for trend = 0.996). Coffee consumption was also not associated with incidence of either proximal or distal colon cancer. We conclude that coffee consumption is not associated with the incidence risk of colorectal cancer in the general population in Japan. © 2006 Wiley‐Liss, Inc.
MascotDatfile: An open‐source library to fully parse and analyse MASCOT MS/MS search results
Authors: Helsens Kenny , Martens Lennart , Vandekerckhove Joël , Gevaert Kris
Published: January 2007

MS‐based protein identification is an important part of both gel‐based and gel‐free proteome studies. The MASCOT search engine (http://www.matrixscience.com) provides one of the most popular automated algorithms for this task. Here we present an open‐source software library written in Java that parses raw MASCOT results into an easily accessible and fully functional object model (http://genesis.ugent.be/MascotDatfile). Several scripts based on this library are provided as examples, allowing direct automation of important routine tasks involved in processing peptide identifications.
Evaluation of a black‐box estimation tool: A case study
Authors: Abran Alain , Ndiaye Iphigénie , Bourque Pierre
Published: January 2007

For the past 30 years, various estimation models and tools have been developed to help managers perform estimation tasks. Some of these estimation tools date from the late 1970s, and have been progressively modernized by their vendors in terms of tools' user interfaces and new functions to facilitate not only project estimation but also detailed project planning. For organizations interested in using such estimation tools, it is crucial to know about their predictive performance. However, it is not an industry practice for the vendors to document the performance of these commercial estimation tools; estimation tool builders have not provided information on the performance of their models with respect to their own initial data repositories, nor on subsequent versions. Basically, such estimation tools are often black boxes with undocumented performance properties.

Various researchers have attempted to analyze the performance of such black‐box estimation tools within the constraints of research data sets that were fairly small compared to the larger ones as claimed by tool vendors. The research presented here revisits this issue, this time with a much larger data set from the International Software Benchmarking Standards Group (ISBSG). This new study is presented in three steps. First, the data set is analyzed by the programming language and corresponding subsamples are identified, including identification of obvious outliers with respect to effort and size. Second, estimation models are built directly from such samples, in a white‐box fashion, with and without outliers. Third, a commercial software estimation tool widely distributed throughout the world is tested against the same set of samples. In summary, for the majority of samples available, the black‐box tool fares fairly poorly. Lessons learned are of two types: prospective tool users should demand that tool vendors benchmark their black‐box tool against publicly available repositories; and the interval of confidence of the output provided by their tool, as well as the basis for such output (e.g. in terms of both the number of observations and currentness of such data), must be documented. Copyright © 2007 John Wiley & Sons, Ltd.
Interaction of (n−3) and (n−6) fatty acids in desaturation and chain elongation of essential fatty acids in cultured glioma cells
Authors: Cook Harold W. , Spence Matthew W.
Published: January 2007

Recent research in various biological systems has revived interest in interactions between the (n−6) and (n−3) essential fatty acids. We have utilized cultured glioma cells to show that linolenic acid, 18∶3(n−3), is rapidly desaturated and chain elongated; 20∶5(n−3) is the major product and accumulates almost exclusively in phospholipids. We examined effects of various (n−6), (n−3), (n−9) and (n−7) fatty acids at 40 μM concentration on desaturation and chain elongation processes using [1‐14C]18∶3(n−3) as substrate. In general, monoenoic fatty acids were without effect. The (n−6) fatty acids (18∶2, 18∶3, 20∶3, 20∶4 and 22∶4) had little effect on total product formed. There was a shift of labeled product to triacylglycerol, and in phospholipids, slightly enhanced conversion of 20∶5 to 22∶5 was evident. In contrast, 22∶6(n−3) was inhibitory, whereas 20∶3(n−3) and 20∶5(n−3) had much less effect. At concentrations <75 μM, all acids were inhibitory. Most products were esterified to phosphatidylcholine, but phosphatidylethanolamine also contained a major portion of 20∶5 and 22∶5. We provide a condensed overview of how the (n−6) and (n−3) fatty acids interact to modify relative rates of desaturation and chain elongation, depending on the essential fatty acid precursor. Thus, the balance between these dietary acids can markedly influence enzymes providing crucial membrane components and substrates for biologically active oxygenated derivatives.
Metabolism in humans ofcis‐12,rans‐15‐octadecadienoic acid relative to palmitic, stearic, oleic and linoleic acids
Authors: Emken E. A. , Rohwedder W. K. , Adlof R. O. , Rakoff H. , Gulley R. M.
Published: January 2007

Mixtures of triglycerides containing deuterium‐labeled hexadecanoic acid (16∶0), octadecanoic acid (18∶0),cis‐9‐octadecenoic acid (9c–18∶1),cis‐9,cis‐12‐octadecadienoic acid (9c, 12c–18∶2) andcis‐12,trans‐15‐octadecadienoic acid (12c,15t–18∶2) were fed to two young‐adult males. Plasma lipid classes were isolated from samples collected periodically over 48 hr. Incorporation and turnover of the deuterium‐labeled fats in plasma lipids were followed by gas chromatography‐mass spectrometry (GC‐MS) analysis of the methyl ester derivatives. Absorption of the deuterated fats was followed by GC‐MS analysis of chylomicron triglycerides isolated by ultracentrifugation.

Results were the following: (i) endogenous fat contributed about 40% of the total fat incorporated into chylomicron triglycerides; (ii) elongation, desaturation and chain‐shortened products from the deuterated fats were not detected; (iii) the polyunsaturated isomer 12c,15t–18∶2 was metabolically more similar to saturated and 9c–18∶1 fatty acids than to 9c,12c–18∶2 (iv) relative incorporation of 9c,12c–18∶2 into phospholipids did not increase proportionally with an increase of 9c,12c–18∶2 in the mixture of deuterated fats fed; (v) absorption of 16∶0, 18∶0, 9c–18∶1, 9c,12c–18∶2 and 12c,15t–18∶2 were similar; and (vi) data for the 1‐ and 2‐acyl positions of phosphatidylcholine and for cholesteryl ester fractions reflected the known high specificity of phosphatidylcholine acyltransferase and lecithin:cholesteryl acyltransferase for 9c,12c–18∶2.

These results illustrate that incorporation of dietary fatty acids into human plasma lipid classes is selectively controlled and that incorporation of dietary 9c,12c–18∶2 is limited. These results suggest that nutritional benefits of diets high in 9c,12c–18∶2 may be of little value to normal subjects and that the 12c,15t–18∶2 isomer in hydrogenated fat is not a nutritional liability at the present dietary level.