bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional significance of four successive glycine residues in the pyrophosphate binding loop of fungal 6‐oxopurine phosphoribosyltransferases
Authors: Moynié Lucile , Giraud Marie‐France , Breton Annick , Boissier Fanny , Daignan‐Fornier Bertrand , Dautant Alain
Published: May 2012

Hypoxanthine‐guanine phosphoribosyltransferase (HGPRT) is a key enzyme of the purine recycling pathway that catalyzes the conversion of 5‐phospho‐ribosyl‐α‐1‐pyrophosphate and guanine or hypoxanthine to guanosine monophosphate (GMP) or inosine monophosphate (IMP), respectively, and pyrophosphate (PPi). We report the first crystal structure of a fungal 6‐oxopurine phosphoribosyltransferase, the Saccharomyces cerevisiae HGPRT (Sc‐HGPRT) in complex with GMP. The crystal structures of full length protein with (WT1) or without (WT2) sulfate that mimics the phosphate group in the PPi binding site were solved by molecular replacement using the structure of a truncated version (Δ7) solved beforehand by multiwavelength anomalous diffusion. Sc‐HGPRT is a dimer and adopts the overall structure of class I phosphoribosyltransferases (PRTs) with a smaller hood domain and a short two‐stranded parallel β‐sheet linking the N‐ to the C‐terminal end. The catalytic loops in WT1 and WT2 are in an open form while in Δ7, due to an inter‐subunit disulfide bridge, the catalytic loop is in either an open or closed form. The closure is concomitant with a peptide plane flipping in the PPi binding loop. Moreover, owing the flexibility of a GGGG motif conserved in fungi, all the peptide bonds of the phosphate binding loop are in trans conformation whereas in nonfungal 6‐oxopurine PRTs, one cis‐peptide bond is required for phosphate binding. Mutations affecting the enzyme activity or the previously characterized feedback inhibition by GMP are located at the nucleotide binding site and the dimer interface.
Testing anisotropic string compactifications in the lab
Authors: Cicoli M.
Published: May 2012

We derive type IIB vacua which are very promising to put string theory to experimental test. These are Calabi‐Yau compactifications with a 4D fibration over a 2D base. The moduli are fixed in such a way to obtain a very anisotropic configuration where the size of the 2D base is exponentially larger than the size of the 4D fibre. These provide stringy realisations of the supersymmetric large extra dimensions scenario and extensions of the ADD scenario which are characterised by TeV‐scale strings and two micron‐sized extra dimensions. We also study the phenomenological properties of hidden Abelian gauge bosons which mix kinetically with the ordinary photon and get a mass via the Green‐Schwarz mechanism. We show that anisotropic compactifications lead naturally to dark forces for an intermediate string scale or even to a hidden CMB for the extreme case of TeV‐scale strings.
Solution structure and small angle scattering analysis of TraI (381–569)
Authors: Wright Nathan T. , Raththagala Madushi , Hemmis Casey W. , Edwards Sheldon , Curtis Joseph E. , Krueger Susan , Schildbach Joel F.
Published: May 2012

TraI, the F plasmid‐encoded nickase, is a 1756 amino acid protein essential for conjugative transfer of plasmid DNA from one bacterium to another. Although crystal structures of N‐ and C‐terminal domains of F TraI have been determined, central domains of the protein are structurally unexplored. The central region (between residues 306 and 1520) is known to both bind single‐stranded DNA (ssDNA) and unwind DNA through a highly processive helicase activity. Here, we show that the ssDNA binding site is located between residues 381 and 858, and we also present the high‐resolution solution structure of the N‐terminus of this region (residues 381–569). This fragment folds into a four‐strand parallel β sheet surrounded by α helices, and it resembles the structure of the N‐terminus of helicases such as RecD and RecQ despite little sequence similarity. The structure supports the model that F TraI resulted from duplication of a RecD‐like domain and subsequent specialization of domains into the more N‐terminal ssDNA binding domain and the more C‐terminal domain containing helicase motifs. In addition, we provide evidence that the nickase and ssDNA binding domains of TraI are held close together by an 80‐residue linker sequence that connects the two domains. These results suggest a possible physical explanation for the apparent negative cooperativity between the nickase and ssDNA binding domain. Proteins 2012; © 2012 Wiley Periodicals, Inc.
Cysteine racemization during the Fmoc solid phase peptide synthesis of the Nav1.7‐selective peptide – protoxin II
Authors: Park Jae H. , Carlin Kevin P. , Wu Gang , Ilyin Victor I. , Kyle Donald J.
Published: May 2012

Protoxin II is biologically active peptide containing the inhibitory cystine knot motif. A synthetic version of the toxin was generated with standard Fmoc solid phase peptide synthesis. If N‐methylmorpholine was used as a base during synthesis of the linear protoxin II, it was found that a significant amount of racemization (approximately 50%) was observed during the process of cysteine residue coupling. This racemization could be suppressed by substituting N‐methylmorpholine with 2,4,6‐collidine. The crude linear toxin was then air oxidized and purified. Electrophysiological assessment of the synthesized protoxin II confirmed its previously described interactions with voltage‐gated sodium channels. Eight other naturally occurring inhibitory knot peptides were also synthesized using this same methodology. The inhibitory potencies of these synthesized toxins on Nav1.7 and Nav1.2 channels are summarized. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.
Surface analysis of Al‐Mg alloy series for ship after cavitation test
Authors: Lee Seung‐Jun , Kim Kyu‐Hwan , Kim Seong‐Jong
Published: May 2012

Aluminum alloys for ships have high mechanical strength and light, and their specific strength is higher than steel ships, enabling high speed and light weight. To lengthen the life of aluminum alloy ships, many studies are being conducted to improve durability through heat treatment and the addition of various elements, but they are still exposed to the harsh ocean environment. As the possibility of cavitation damage is getting higher because of the high speed of aluminum ships, it is critical to select aluminum alloys for ships that have excellent characteristics in ocean environment. For this purpose, cavitation experiments were conducted for the Al‐Mg alloy of the 5000 series as hull materials that directly contact seawater, and their behaviors were examined and compared. The cavitation experiments revealed that the 5083‐O and the 5083‐H116 alloys showed the largest and the smallest weight loss, respectively. Copyright © 2012 John Wiley & Sons, Ltd.
ToF‐SIMS study of phosphorus diffusion in low‐dimensional silicon structures
Authors: Perego Michele , Seguini Gabriele , Fanciulli Marco
Published: May 2012

Doping of Si nanocrystals is expected to be crucial in order to tailor the properties of these nanostructures and to implement their technological applications. In this work, phosphosilicate ultra‐thin films (P δ‐layers) were buried in an SiO/SiO2 multilayer structure, and the redistribution of P atoms during high‐temperature (800–1100 °C) thermal treatments was studied by means of ToF‐SIMS depth profiling. We demonstrated that the presence of the surrounding SiO2 matrix provides a strong barrier to P diffusion and, for temperatures equal or above 1000 °C, induces P segregation in the SiO regions, where two‐dimensional layers of Si nanocrystals are formed during the thermal treatment. Such an effect is qualitatively in agreement with the P diffusivity data reported in the literature. The amount of P atoms incorporated in the Si nanocrystal region is directly controlled through a limited source process by properly adjusting the thickness of the P δ‐layer interposed between the SiO and SiO2 films. Copyright © 2012 John Wiley & Sons, Ltd.
Knowledge: A Measurable Universal Phenomenon of Life
Authors: Simms James R. , Johnson Patrick J.
Published: May 2012

This article describes the development of the fundamental principles of the science of life, which are equivalent to those of the natural (hard) sciences, such as physics and chemistry. The natural sciences are typified by identification of universal phenomena, relations among these phenomena and fundamental measures and units of measure for these phenomena. It is shown that matter, energy, knowledge, information and behaviour are universal phenomena of life and that there are relations among these phenomena. Units of measure for these phenomena were previously developed, except for knowledge. The principles of life sciences are developed using the natural sciences (Newton) development model. Names are also suggested for new dimensions of quantitative measures of biochemical, genetic and neural knowledge. Copyright © 2012 John Wiley & Sons, Ltd.
Effect of Titanium Addition on As Cast Structure and Macrosegregation of High‐Carbon High‐Chromium Steel
Authors: Razavinejad Reza , Firoozi Sadegh , Mirbagheri Seyed Mohammad Hossein
Published: May 2012

In casting heavy ingots of high‐chromium high‐carbon cold work steels, macrosegregation develops in the center of the ingot, causing difficulties during subsequent hot working. Heat transfer and solidification of an industrial scale high‐carbon high‐chromium steel ingot was simulated and thereafter a laboratory scale representative ingot was designed to model the solidification of the industrial scale ingot. Titanium in the range of 0.3–1% was added to the high‐chromium high‐carbon (12%Cr–2%C) steel during melting process. Microstructures, macrosegregation and phase formations were studied using optical microscopy, scanning electron microscopy, energy dispersive X‐ray spectrometry, wave dispersive X‐ray spectrometry, optical emission spectroscopy, and X‐ray diffraction. Addition of 0.3% titanium was sufficient to diminish the macrosegregation; however it did not have a significant effect on the grain size. Addition of 0.7 and 1% titanium had a substantial effect on grain size in the longitudinal direction and refined the primary carbides structure. The formation of small TiC carbides that precipitated before solidification of liquid iron acted as nuclei for primary pro‐eutectic austenite grains.
The Enhanced Even and Pitting Corrosion Resistances of Bulk Nanocrystalline Steel in HCl Solution
Authors: Wang Sheng‐Gang , Sun Miao , Long Kang
Published: May 2012

We studied the corrosion properties of bulk nanocrystalline 304 stainless steel (BN‐SS304) produced by severe rolling technique and conventional polycrystalline 304 stainless steel (CP‐SS304) with immersion test, X‐ray photoelectron spectroscopy, ultra‐violet photoelectron spectroscopy, inductively coupled plasma emission spectrometer, and scanning electron microscope. Immersion test was carried out in 0.5 mol L−1 HCl solution for 30 days immersion interval at room temperature. It is well known that the pitting corrosion of stainless steel could be inevitable in solution containing Cl−. However, BN‐SS304 can scarcely suffer from pitting corrosion with the compact oxide film on its corrosion surface and less corrosion rate in comparison with CP‐SS304. The less corrosion rate of BN‐SS304 was attributed to the stronger O2 adsorption and compact oxide film on its corrosion surface, its less weight of 4s–4s valence electrons and its larger work function in comparison with CP‐SS304. The improved pitting corrosion resistance of BN‐SS304 resulted from the compact oxide film, weaker Cl− adsorption and less Cl− chemical activity on its corrosion surface.
Reframing the Biotechnology Debate: The Deconstructive Efforts of the Council for Responsible Genetics
Authors: Zschau Tony , Adams Alison E. , Shriver Thomas E.
Published: May 2012

We demonstrate the analytical utility of social movement theory for understanding the framing efforts of the anti‐biotechnology movement. We content‐analyzed electronic and printed documents from the anti‐biotech watchdog group, the Council of Responsible Genetics to identify the movement's diagnostic and prognostic framing efforts. Our findings suggest that while the organization blends frame extension and frame translation strategies it aims for a more radical frame transformation project. Moving the public debate away from overly technical and scientized frames toward issues of social utility and democracy, it tries to recast biotechnologies as a violation of individual and collective rights. Drawing from our findings we offer a number of suggestions for how future research can help further illuminate the interactive and discursive realities of modern technological developments.
Optimal design of broadband radome using particle swarm optimization
Authors: Chiba Hidetoshi , Nishizawa Kazushi , Miyashita Hiroaki , Konishi Yoshihiko
Published: May 2012

This paper presents an optimal radome design using particle swarm optimization (PSO) which has recently drawn considerable attention in a wide range of applications. The frequency characteristics of the transmission coefficient for the radome are adopted as the objective function, and the radome wall thickness and radome shape are optimized. Furthermore, in order to enhance the reliability of the original PSO, we introduce a concept analogous to ‘mutation’ in genetic algorithms. Numerical experiments reveal that the mutation operation is capable of considerably enhancing the stability and the reliability of the PSO. We also confirm that the PSO is successfully applied to the problem of a practical radome design, and the transmission coefficient attained by the PSO is above the targeted value of −1 dB for the entire frequency bandwidth and for all evaluated beam scan angles. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Incorporating reserve supplying demand response in customer's decision making model for simultaneous energy and reserve markets
Authors: Behrangrad Mahdi , Sugihara Hideharu , Funaki Tsuyoshi
Published: May 2012

In this letter, the customer profit‐maximization‐model is expanded to incorporate the probabilistic profit of reserve supply. This extended model will change the customer behavior and therefore will affect the system performance. The analysis of the extended model is carried out to show how this model, considering energy and reserve market parameters, affects the customer decision. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Sonographic assessment of normal and abnormal patterns of fetal cerebral lamination
Authors: Pugash D. , Hendson G. , Dunham C. P. , Dewar K. , Money D. M. , Prayer D.
Published: May 2012

Objectives

Prenatal development of the brain is characterized by gestational age‐specific changes in the laminar structure of the brain parenchyma before 30 gestational weeks. Cerebral lamination patterns of normal fetal brain development have been described histologically, by postmortem in‐vitro magnetic resonance imaging (MRI) and by in‐vivo fetal MRI. The purpose of this study was to evaluate the sonographic appearance of laminar organization of the cerebral wall in normal and abnormal brain development.

Methods

This was a retrospective study of ultrasound findings in 92 normal fetuses and 68 fetuses with abnormal cerebral lamination patterns for gestational age, at 17–38 weeks' gestation. We investigated the visibility of the subplate zone relative to the intermediate zone and correlated characteristic sonographic findings of cerebral lamination with gestational age in order to evaluate transient structures.

Results

In the normal cohort, the subplate zone–intermediate zone interface was identified as early as 17 weeks, and in all 57 fetuses examined up to 28 weeks. In all of these fetuses, the subplate zone appeared anechoic and the intermediate zone appeared homogeneously more echogenic than did the subplate zone. In the 22 fetuses between 28 and 34 weeks, there was a transition period when lamination disappeared in a variable fashion. The subplate zone–intermediate zone interface was not identified in any fetus after 34 weeks (n = 13). There were three patterns of abnormal cerebral lamination: (1) no normal laminar pattern before 28 weeks (n = 32), in association with severe ventriculomegaly, diffuse ischemia, microcephaly, teratogen exposure or lissencephaly; (2) focal disruption of lamination before 28 weeks (n = 24), associated with hemorrhage, porencephaly, stroke, migrational abnormalities, thanatophoric dysplasia, meningomyelocele or encephalocele; (3) increased prominence and echogenicity of the intermediate zone before 28 weeks and/or persistence of a laminar pattern beyond 33 weeks (n = 10), associated with Type 1 lissencephaly or CMV infection. There was a mixed focal/diffuse pattern in two fetuses. In CMV infection, the earliest indication of the infection was focal heterogeneity and increased echogenicity of the intermediate zone, which predated the development of microcephaly, ventriculomegaly and intracranial calcification.

Conclusions

The fetal subplate and intermediate zones can be demonstrated reliably on routine sonography before 28 weeks and disappear after 34 weeks. These findings represent normal gestational age‐dependent transient laminar patterns of cerebral development and are consistent with histological studies. Abnormal fetal cerebral lamination patterns for gestational age are also visible on sonography, and may indicate abnormal brain development. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Lesion size affects diagnostic performance of IOTA logistic regression models, IOTA simple rules and risk of malignancy index in discriminating between benign and malignant adnexal masses
Authors: Di Legge A. , Testa A. C. , Ameye L. , Van Calster B. , Lissoni A. A. , Leone F. P. G. , Savelli L. , Franchi D. , Czekierdowski A. , Trio D. , Van Holsbeke C. , Ferrazzi E. , Scambia G. , Timmerman D. , Valentin L.
Published: May 2012

Objectives

To estimate the ability to discriminate between benign and malignant adnexal masses of different size using: subjective assessment, two International Ovarian Tumor Analysis (IOTA) logistic regression models (LR1 and LR2), the IOTA simple rules and the risk of malignancy index (RMI).

Methods

We used a multicenter IOTA database of 2445 patients with at least one adnexal mass, i.e. the database previously used to prospectively validate the diagnostic performance of LR1 and LR2. The masses were categorized into three subgroups according to their largest diameter: small tumors (diameter < 4 cm; n = 396), medium‐sized tumors (diameter, 4–9.9 cm; n = 1457) and large tumors (diameter ≥ 10 cm, n = 592). Subjective assessment, LR1 and LR2, IOTA simple rules and the RMI were applied to each of the three groups. Sensitivity, specificity, positive and negative likelihood ratio (LR+, LR−), diagnostic odds ratio (DOR) and area under the receiver–operating characteristics curve (AUC) were used to describe diagnostic performance. A moving window technique was applied to estimate the effect of tumor size as a continuous variable on the AUC. The reference standard was the histological diagnosis of the surgically removed adnexal mass.

Results

The frequency of invasive malignancy was 10% in small tumors, 19% in medium‐sized tumors and 40% in large tumors; 11% of the large tumors were borderline tumors vs 3% and 4%, respectively, of the small and medium‐sized tumors. The type of benign histology also differed among the three subgroups. For all methods, sensitivity with regard to malignancy was lowest in small tumors (56–84% vs 67–93% in medium‐sized tumors and 74–95% in large tumors) while specificity was lowest in large tumors (60–87%vs 83–95% in medium‐sized tumors and 83–96% in small tumors ). The DOR and the AUC value were highest in medium‐sized tumors and the AUC was largest in tumors with a largest diameter of 7–11 cm.

Conclusion

Tumor size affects the performance of subjective assessment, LR1 and LR2, the IOTA simple rules and the RMI in discriminating correctly between benign and malignant adnexal masses. The likely explanation, at least in part, is the difference in histology among tumors of different size. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
First‐trimester combined screening for trisomy 21 with different combinations of placental growth factor, free β‐human chorionic gonadotropin and pregnancy‐associated plasma protein‐A
Authors: Kagan K. O. , Hoopmann M. , Abele H. , Alkier R. , Lüthgens K.
Published: May 2012

Objective

To examine placental growth factor (PlGF) in euploid and trisomy 21 pregnancies at 11–13 weeks' gestation and to model the impact on first‐trimester combined screening.

Methods

PlGF was measured in 509 (409 euploid and 100 trisomic) fetal serum samples derived from prospective first‐trimester combined screening for trisomy 21 at 11–13 weeks' gestation. The serum samples were stored at −80°C, following the measurement of free β‐human chorionic gonadotropin (β‐hCG) and pregnancy‐associated plasma protein‐A (PAPP‐A) levels, for median time spans of 0.9 and 4.1 years in the euploid and trisomy 21 pregnancies, respectively. The effect of additional PlGF measurement at the time of combined screening was investigated by simulating fetal nuchal translucency (NT) measurements and multiples of the median (MoM) values for PAPP‐A, free β‐hCG and PlGF for 20 000 euploid and 20 000 trisomy 21 pregnancies. Patient‐specific combined risks were calculated based on maternal age and fetal NT in addition to free β‐hCG, PAPP‐A and PlGF, PAPP‐A and PlGF or free β‐hCG and PlGF, and detection and false‐positive rates were calculated.

Results

Median PlGF‐MoM was 1.0 (95% confidence interval (CI), 0.96–1.04) in euploid fetuses and significantly lower, at 0.73 (95% CI, 0.70–0.76), in trisomy‐21 fetuses (P < 0.0001). There was no significant dependency between PlGF‐MoM and either gestational age at the time of blood sampling (r = 0.087, P = 0.392) or sample storage time (r = 0.028, P = 0.785). Modeled detection and false‐positive rates for first‐trimester combined screening (based on maternal and gestational age, fetal NT and maternal serum biochemistry) without PlGF were 85% and 2.7% for a fixed risk cut‐off of 1:100. The addition of PlGF increased the detection rate to 87% and reduced the false‐positive rate to 2.6%. Screening by maternal age and fetal NT in combination with PlGF and PAPP‐A or in combination with PlGF and free β‐hCG provided detection rates of 82% and 79%, with false‐positive rates of 2.7% and 3.0%, respectively.

Conclusion

In pregnancies with trisomy 21 PlGF is reduced. The impact on the overall screening performance for trisomy 21 is low and does not justify the measurement of PlGF solely for trisomy 21 screening. However, as PlGF is measured with the aim of assessing the risk for pre‐eclampsia, further improvement in screening for trisomy 21 can be considered as an added benefit.
The rank transformation—an easy and intuitive way to connect many nonparametric methods to their parametric counterparts for seamless teaching introductory statistics courses
Authors: Conover W. Jay
Published: May 2012

The rank transformation refers to replacing the data by their ranks, or average ranks in case of ties, prior to performing standard statistical procedures on the ranks. There are several forms of transforming the data to ranks. RT‐1 refers to ranking all of the data together, and giving the smallest observation the rank 1, the second smallest the rank 2, and so on. RT‐2 involves ranking data within subgroups only, and not comparing data across subgroups. RT‐3 involves re‐expressing the data prior to ranking, such as subtracting a sample mean or median from the data and taking an absolute value of the difference prior to ranking. RT‐4 describes situations where data are re‐expressed within subgroups, and then ranked within subgroups.

The rank transformation is a convenient way to bridge the pedagogical gap between parametric and nonparametric methods in statistics. First present the classical statistical procedure, such as a t test or a correlation coefficient, and then perform the same operation on the ranks of the data instead of the data themselves. The resulting method is equivalent to the standard presentation of nonparametric methods, and is amenable to convenient use in computer software. Limitations of this method are also described. WIREs Comput Stat 2012 doi: 10.1002/wics.1216

This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Nonparametric Methods

Statistical and Graphical Methods of Data Analysis > Transformations
Life‐History Patterns of Cuban Poeciliid Fishes (Teleostei: Cyprinodontiformes)
Authors: Ponce de León José L. , Rodríguez Rodet , León Gunnary
Published: May 2012

The following work provides basic information about the life history of 10 Cuban species of the family Poeciliidae. Adult fish stocks were captured in their natural habitat, and litters obtained from them were raised and maintained in captivity for 19 weeks. For each species, we present the mean value of newborn length (TLo), age at sexual maturity (AM), total length at sexual maturity (TLM), as well as the patterns of postnatal growth in aquarium conditions, which were described using size–age curves and nonlinear regression equations (Richards model). There are differences in growth dynamics among species. In general, growth rates differ for both sexes in all poeciliids studied, males maturing earlier than females, who reach higher values of total length at the 19th week (TLf). Sexual size dimorphism could be explained by the specific roles of each sex (fecundity in females and early maturity in males) while differences in growth among species could be related to their distribution patterns in the wild. The data summarized in this contribution can be useful for the conservation of these fish species. Zoo Biol 32:251–256, 2013. © 2012 Wiley Periodicals, Inc.
Feasibility and short‐term outcome of adjuvant FOLFOX after resection of colorectal liver metastases
Authors: Sakamoto Yasuo , Beppu Toru , Miyamoto Yuji , Okabe Hirohisa , Ida Satoshi , Imai Katsunori , Chikamoto Akira , Watanabe Masayuki , Takamori Hiroshi , Baba Hideo
Published: May 2012

Background

The role of adjuvant chemotherapy for stage IV colorectal cancer has so far been under‐investigated. The aim of this study was to assess the feasibility and short‐term outcome of adjuvant chemotherapy with the FOLFOX regimen following liver resection for patients with colorectal liver metastasis (CRLM).

Methods

From May 2005 to September 2010, 86 patients with CRLM underwent hepatic resection in the Department of Gastroenterological Surgery, Graduate School of Medical Sciences, Kumamoto University. Of these patients, 24 received FOLFOX4 or modified FOLFOX6 as postoperative adjuvant chemotherapy.

Results

Nineteen male and 5 female patients received adjuvant chemotherapy following liver resection. Twenty‐one (87.5 %) of these patients completed 6 cycles of adjuvant chemotherapy. Five patients required a dose reduction due to neutropenia, and the dose intensities of oxaliplatin and 5‐FU were 93.6 and 94.1 %, respectively. There were no severe adverse events from the treatments. The median follow‐up period was 48.4 months. Recurrences developed in 12 patients, and 3 patients died during the follow‐up period. The 3‐ and 5‐year disease‐free survival and overall survival were 51.6 and 45.1 % and 95.5 and 76.0 %, respectively.

Conclusions

Adjuvant FOLFOX is feasible and might provide a good prognosis for CRLM patients who undergo liver resection.
Workforce Participation Barriers for People With Disability
Authors: Hogan Anthony , Kyaw-Myint Su Mon , Harris Debra , Denronden Harmony
Published: May 2012

Access to meaningful and equitably paid work is an ongoing issue facing people with disabilities across the world. This article is concerned with the nature and extent of workplace accommodation currently made available in Australia to people with disabilities. The article is based on analysis of theAustralian Survey of Disability Ageing and Carers(2003). The article first ratifies existing findings in the literature that people with disability are less likely to be employed and where employed, are likely to be underemployed and underpaid. Restrictions in the ability to participate in paid work without accommodations were common with the need for accommodation varying from 43% through to 91%, depending on the nature of disability experienced. We identify the possibility that people with disability self-select themselves into workplaces where they can self-accommodate their own access needs. Generally, the extent of workplace accommodations provided were low (12%–27%). Known stratifying factors (gender, ethnicity, and education) exacerbated existing barriers to accessing employment. Workers with higher training needs were less likely to secure employment while people accessing the workplace with the benefit of an advocate were more likely to be in the workforce. Strategies for enhancing employment outcomes are discussed.
Wakes behind a prolate spheroid in crossflow
Authors: El Khoury George K. , Andersson Helge I. , Pettersen Bjørnar
Published: May 2012

Viscous laminar flow past a prolate$(L/ d= 6)$spheroid has been investigated numerically at seven different Reynolds numbers;$\mathit{Re}= 50, 75, 100, 150, 200, 250$and$300$. In contrast to all earlier investigations, the major axis of the spheroid was oriented perpendicular to the free stream flow. As expected, the flow field in the wake showed a strong resemblance of that observed behind a finite-length circular cylinder, yet had features observed in the axisymmetric wake behind a sphere. The following different flow regimes were observed in the present computational study: (i) steady laminar flow with massive flow separation and symmetry about the equatorial and the meridional planes at$\mathit{Re}= 50$; (ii) steady laminar flow with massive flow separation and symmetry about the equatorial and the meridional plane at$\mathit{Re}= 75$, but the flow in the equatorial plane did no longer resemble the steady wake behind a circular cylinder; (iii) unsteady laminar flow with Strouhal number$0. 109$and symmetry about the equatorial plane at$\mathit{Re}= 100$; (iv) unsteady laminar flow with two distinct frequencies and without any planar symmetries at$\mathit{Re}= 200$; (v) transitional flow with a dominant shedding frequency$\mathit{St}= 0. 151$and without any spatial symmetries at$\mathit{Re}= 300$. For all but the two lowest$\mathit{Re}$hairpin vortices were alternately shed from the two sides of the spheroid and resulted in a ladder-like pattern of oppositely oriented vortex structures, in contrast with the single-sided shedding in the wake of a sphere. The contour of the very-near-wake mimicked the shape of the prolate spheroid. However,$15d$downstream the major axis of the wake became aligned with the minor axis of the spheroid. This implies that an axis switching occurred some$10d$downstream, i.e. the cross-section of the wake evolved such that the major and minor axes interchanged at a certain downstream location. This peculiar phenomenon has frequently been reported to arise for elliptical and rectangular jets, whereas observations of axis switching for asymmetric wakes are scarce.
Hydrodynamic and thermodiffusive instability effects on the evolution of laminar planar lean premixed hydrogen flames
Authors: Altantzis C. , Frouzakis C. E. , Tomboulides A. G. , Matalon M. , Boulouchos K.
Published: May 2012

Numerical simulations with single-step chemistry and detailed transport are used to study premixed hydrogen/air flames in two-dimensional channel-like domains with periodic boundary conditions along the horizontal boundaries as a function of the domain height. Both unity Lewis number, where only hydrodynamic instability appears, and subunity Lewis number, where the flame propagation is strongly affected by the combined effect of hydrodynamic and thermodiffusive instabilities are considered. The simulations aim at studying the initial linear growth of perturbations superimposed on the planar flame front as well as the long-term nonlinear evolution. The dispersion relation between the growth rate and the wavelength of the perturbation characterizing the linear regime is extracted from the simulations and compared with linear stability theory. The dynamics observed during the nonlinear evolution depend strongly on the domain size and on the Lewis number. As predicted by the theory, unity Lewis number flames are found to form a single cusp structure which propagates unchanged with constant speed. The long-term dynamics of the subunity Lewis number flames include steady cell propagation, lateral flame movement, oscillations and regular as well as chaotic cell splitting and merging.
Oscillatory sensitivity patterns for global modes in wakes
Authors: Tammisola Outi
Published: May 2012

Globally unstable wakes with co-flow at intermediate Reynolds numbers are studied, to quantify important spatial regions for the development and control of the global instability. One region of high structural sensitivity is found close to the inlet for all wakes, in agreement with previous findings for cylinder wakes. A second, elongated region of high structural sensitivity is seen downstream of the first one for unconfined wakes at$\mathit{Re}= 400$. When base-flow modifications are considered, a spatially oscillating sensitivity pattern is found inside the downstream high-structural-sensitivity region. This implies that the same change in the base flow can either destabilize or stabilize the flow, depending on the exact position where it is applied. It is shown that the sensitivity pattern remains unchanged for different choices of streamwise boundary conditions and numerical resolution. The actual base-flow is modified in selected configurations, and the linear global modes recomputed. It is confirmed that the linear global eigenvalues move according to the predicted sensitivity pattern for small-amplitude base-flow modifications, for which the theory applies. We also look at the implications of a small control cylinder for the flow. Only the upstream high-sensitivity region proves to be robust in terms of control, but one should be careful not to disturb the flow in the downstream high-sensitivity region, in order to achieve control. The findings can have direct implications for the numerical resolution requirements for wakes at higher Reynolds numbers. Furthermore, they provide one more possible explanation for why confined wakes have a more narrow frequency spectrum than unconfined wakes.
On the anisotropy of a low-Reynolds-number grid turbulence
Authors: Djenidi L. , Tardu S. F.
Published: May 2012

The anisotropy of a low-Reynolds-number grid turbulence is investigated through direct numerical simulations based on the lattice Boltzmann method. The focus is on the anisotropy of the Reynolds-stress (${b}_{ij} $) and Reynolds-stress dissipation-rate (${d}_{ij} $) tensors and the approach taken is that using the invariant analysis introduced by Lumley & Newman (J. Fluid Mech., vol. 82, 1977, pp. 161–178). The grid is made up of thin square floating elements in an aligned configuration.

The anisotropy is initially high behind the grid and decays quickly as the downstream distance increases. The anisotropy invariant map (AIM) analysis shows that the return-to-isotropic trend of both ${b}_{ij} $ and ${d}_{ij} $ is fast and follows a perfectly axisymmetic expansion, although just behind the grid there is an initial tendency toward a one-component state. It is found that the linear relation ${d}_{ij} = A{b}_{ij} $ with $A= 0. 21$ is satisfied during the return-to-isotropy phase of the turbulence decay, although close to the grid a form ${d}_{ij} = f({b}_{ij} )$, where $f$ is a nonlinear function of ${b}_{ij} $, is more appropriate. For large downstream distances, ${d}_{ij} $ becomes almost independent of ${b}_{ij} $, suggesting that despite the absence of an inertial range, the (dissipative) small scales present a high degree of isotropy. It is argued that (i) the very small values of the mean strain rate and (ii) the weak anisotropy of the large scales are in fact responsible for this result.
Resonant behaviour of an oscillating wave energy converter in a channel
Authors: Renzi Emiliano , Dias F.
Published: May 2012

A mathematical model is developed to study the behaviour of an oscillating wave energy converter in a channel. During recent laboratory tests in a wave tank, peaks in the hydrodynamic actions on the converter occurred at certain frequencies of the incident waves. This resonant mechanism is known to be generated by the transverse sloshing modes of the channel. Here the influence of the channel sloshing modes on the performance of the device is further investigated. Within the framework of a linear inviscid potential-flow theory, application of Green’s theorem yields a hypersingular integral equation for the velocity potential in the fluid domain. The solution is found in terms of a fast-converging series of Chebyshev polynomials of the second kind. The physical behaviour of the system is then analysed, showing sensitivity of the resonant sloshing modes to the geometry of the device, which concurs in increasing the maximum efficiency. Analytical results are validated with available numerical and experimental data.
Between town and country: shifting identity and migrant youth in Uganda
Authors: Barratt Caroline , Mbonye Martin , Seeley Janet
Published: May 2012

In Uganda, as in many other African countries, increasing numbers of 15–24 year olds are migrating to urban areas to look for work and educational opportunities. We explore the shifting sense of identity amongst youth migrants in Uganda as they struggle to reconcile the differences in social norms between the rural settings in which they are brought up and the urban environment in which they now live. The experience of migration significantly impacts on the transition from youths to adults by influencing their perception of their own identity as well as the expectations of society. Young people often hold conflicting views of their rural and urban experiences, suggesting that understanding rural and urban realities as distinct entities does not reflect the complex relationship, and possible confusion, of the migrant experience. In contrast to existing literature on migrant identities, which has tended to focus on the identity shift experienced by adult transnational migrants, this reveals the particular challenges faced by youth migrants whose adult self is not yet formed.
HIV/AIDS policies in Mozambique and the new aid architecture: successes, shortcomings and the way forward
Authors: Bidaurratzaga-Aurre Eduardo , Colom-Jaén Artur
Published: May 2012

HIV/AIDS policies have become a significant and controversial issue in Mozambique in recent years. The extent of the disease, along with a massive involvement of the donor community and a committed response by Mozambican authorities, are the main drivers of these policies. In the framework of the new aid architecture, donors are expected to encourage recipient country ‘ownership’ of development policies through new aid instruments like budget support or sector-wide approaches. However, HIV/AIDS policies in Mozambique are highly influenced by donors, because an exceptionally high proportion of the financial resources and policy formation comes from them. In this article we assess the extent of HIV/AIDS and its effects in Mozambique, and analyse the successes and shortcomings of the policies to fight the disease, emphasising the role of donors. We end by exploring possible ways to increase ownership and effectiveness.
Executive dominance and the politics of quota representation in Uganda
Authors: Muriaas Ragnhild L. , Wang Vibeke
Published: May 2012

Quota policies securing the presence of marginalised groups in decision-making bodies have been adopted across sub-Saharan Africa. These policies are frequently understood through the lens of a pluralist perspective. This stance is not appropriate in African regimes characterised by executive dominance. Through a qualitative study of official documents, newspaper articles and interviews conducted during two field studies in Uganda in 2005 and 2010, this article shows how the understanding of quota policies in Africa may gain from the corporatist debate on interest representation. The analysis reveals that the incumbent National Resistance Movement has employed the reserved seat policy strategically to maintain its dominant position, and that strategies for using the quota system have evolved gradually over time in response to key political events, and the interests of group activists at the local and national levels with vested interests in its survival.
Civil–military relations and political order in Guinea-Bissau
Authors: Embaló Birgit
Published: May 2012

Since independence in 1974 the military of Guinea-Bissau have succeeded in controlling the political system, even attempting to impose their rule directly in the aftermath of the 1998/9 war. What makes the analysis of civil–military relations and political order in contemporary Guinea-Bissau particularly challenging is the overlapping of political, ethnic and personal considerations of the politico-military elite and their fluctuating and ambiguous short-term alliances. Guinea-Bissau's armed forces include an amalgam of veterans, claiming historical legitimacy from the liberation war, and officers who use their positions for personal gain rather than furthering democracy and national interests. This article examines the logic of civil–military relations against the heterarchical political figuration and the specific character of the politico-military elite of Guinea-Bissau.
Modelling the effect of individual strategic behaviour on community-level outcomes of conservation interventions
Authors: KEANE AIDAN , JONES JULIA P. G. , MILNER-GULLAND E. J.
Published: May 2012

Many conservation interventions seek to change resource users' behaviour through the creation and enforcement of rules. Their success depends on changing the incentives of potential rule-breakers and those who monitor and enforce compliance. Project implementers may use payments to encourage monitoring and sanctions to deter rule breaking but there has been little research to examine the effectiveness of such approaches in promoting compliance with conservation rules. The effects of payments and sanctions on poaching in a hypothetical community-based conservation project were investigated using an individual-based model incorporating individual heterogeneity and a realistic range of behaviours. Individuals could choose to poach, monitor others' behaviour, or ‘cheat’ (claim a fee without actually monitoring behaviour). They could also invest in avoidance to reduce their probability of being detected breaking rules. Community-level outcomes emerged from individuals’ choices and strategic interactions. The model demonstrates that payments and sanctions can interact strongly with one another and that their effects depend on the economic context in which they are applied. Sanctions were more reliable than payments in reducing poaching and, in some circumstances, payments produced perverse effects. It is thus important to consider individual-level heterogeneity and strategic decision-making when designing interventions aimed at changing human behaviour.
Outbreak of mastitis in sheep caused by multi-drug resistantEnterococcus faecalisin Sardinia, Italy
Authors: SANCIU G. , MAROGNA G. , PAGLIETTI B. , CAPPUCCINELLI P. , LEORI G. , RAPPELLI P.
Published: May 2012

An outbreak of infective mastitis due toEnterococcus faecalisoccurred in an intensive sheep farm in north Sardinia (Italy).E. faecalis, which is only rarely isolated from sheep milk, was unexpectedly found in 22·3% of positive samples at microbiological examination. Forty-five out of the 48E. faecalisisolates showed the same multi-drug resistance pattern (cloxacillin, streptomycin, kanamycin, clindamycin, oxytetracycline).E. faecalisisolates were analysed by pulsed-field gel electrophoresis, and all 45 multi-drug resistant strains showed an indistinguishable macrorestiction profile, indicating their clonal origin. To our knowledge, this is the first report of an outbreak of mastitis in sheep caused byE. faecalis.
A statistical application of the quantile mechanics approach: MTM estimators for the parameters of t and gamma distributions
Authors: KLEEFELD A. , BRAZAUSKAS V.
Published: May 2012

In this paper, we revisit the quantile mechanics approach, which was introduced by Steinbrecher and Shaw (Steinbrecher, G. & Shaw, W. T. (2008) Quantile mechanics. European. J. Appl. Math.19, 87–112). Our objectives are (i) to derive the method of trimmed moments (MTM) estimators for the parameters of gamma and Student's t distributions, and (ii) to examine their large- and small-sample statistical properties. Since trimmed moments are defined through the quantile function of the distribution, quantile mechanics seems like a natural approach for achieving objective (i). To accomplish the second goal, we rely on the general large sample results for MTMs, which were established by Brazauskas et al. (Brazauskas, V., Jones, B. L. & Zitikis, R. (2009) Robust fitting of claim severity distributions and the method of trimmed moments. J. Stat. Plan. Inference139, 2028–2043), and then use Monte Carlo simulations to investigate small-sample behaviour of the newly derived estimators. We find that, unlike the maximum likelihood method, which usually yields fully efficient but non-robust estimators, the MTM estimators are robust and offer competitive trade-offs between robustness and efficiency. These properties are essential when one employs gamma or Student's t distributions in such outlier-prone areas as insurance and finance.
Bait consumption by Sooty Terns: implications for island eradication programmes
Authors: SZTUKOWSKI LISA A. , KESLER DYLAN C.
Published: May 2012

Rat Rattus spp. predation is widely recognised as a major threat to insular seabird populations. Rodent eradication programmes have advanced over the last two decades with purported benefits to ecosystems and seabird conservation. However, the danger of non-target poisoning to seabirds has rarely been examined, despite hundreds of insular eradication efforts. We initiated research to assess the risk of rodenticide bait to nesting Sooty Terns Sterna fuscata on Wake Atoll Complex. Placebo bait with a fluorescing dye was used in a control treatment design to track exposure and ingestion. Camera-based observations and faecal samples, post-mortem inspections and live chick observations suggested that bait exposure and consumption occurred, but that it was infrequent. Results indicated that poison bait eradication should occur outside the chick rearing phase to minimise risks to nesting seabirds. Our study also documents previously unreported environmental fluorescence, which may increase false positive results in pre-eradication assessments of bait palatability, bait uptake rates, and bait application methods that use inactive fluorescing test baits. We recommend that future conservation efforts begin with an evaluation of environmentally-based fluorescence before formal biomarker studies.