bluuebunny/crossref_metadata_2025 huggingface dataset:
The Detection and Characterization of a Nontransiting Planet by Transit Timing Variations
Authors: Nesvorný David , Kipping David M. , Buchhave Lars A. , Bakos Gáspár Á. , Hartman Joel , Schmitt Allan R.
Published: May 2012

Unseen Planet

The orbits of planetary bodies can be affected by gravitational interactions with other planets in the same system. If the planets can be seen to pass in front of their star (or to transit), the gravitational perturbations translate into variations in transit duration.

Nesvorný
et al.

(p.
1133
, published online 10 May; see the Perspective by

Murray

) inferred the presence of a far distant, previously unknown planet from the transit timing variations of a planet previously detected by the Kepler space telescope. The new planet is in a 57-day orbit and does not transit its host star. The analysis also revealed a third possible planet with a mass 1.7 times that of the Earth in a 6.8-day orbit. The radially spaced, roughly coplanar, and nearly circular orbits of the two confirmed planets mirror planetary orbits in our own solar system.
Intertwining Electron Tunneling with Light
Authors: Szymańska Marzena H.
Published: May 2012

The tunneling of electrons through barriers can be controlled when photons are coupled to excited states of electrons trapped in quantum wells.
The Wind at Our Backs
Harvest the Wind
America's Journey to Jobs, Energy Independence, and Climate Stability

by Philip Warburg

Beacon Press, Boston, 2012. 256 pp. $27.95, C$33. ISBN 9780807001073.
Authors: Reicher Dan
Published: May 2012

Building on his interviews with people involved in the development of wind energy, Warburg chronicles the industry's growth and challenges.
Virulence or Competition?
Authors: Sperandio Vanessa
Published: May 2012

Commensal bacteria are necessary to clear pathogenic bacteria from the mammalian intestine during infection.
Reprise of First Experiment Casts Doubt on Supersolid Helium
Authors: Cho Adrian
Published: May 2012

A second pair of physicists has found further evidence that solid helium doesn't flow—ironically, by tweaking the experiment that started the controversy in the first place.
Primeval Land Rises From the Ashes
Authors: Hvistendahl Mara
Published: May 2012

A "vegetational Pompeii" buried in a coal deposit is shedding light on ecosystem structure and climate during the Permian period.
Human Papillomavirus Immunization Is Associated with Increased Expression of Different Innate Immune Regulatory Receptors
Authors: Colmenares V. , Noyola D. E. , Monsiváis-Urenda A. , Salgado-Bustamante M. , Estrada-Capetillo L. , González-Amaro R. , Baranda L.
Published: May 2012

Human papillomavirus (HPV) is able to inhibit the secretion of gamma interferon (IFN-γ) and the expression of some immune innate cell receptors. Immunoglobulin-like transcript 2 (ILT2) is a regulatory receptor that seems to participate in the pathogenesis of viral infections. We have studied the expression and function of ILT2 and the expression of other NK cell receptors in 23 healthy women before and after immunization with the quadrivalent HPV (type 6/11/16/18) vaccine (Gardasil). Receptor expression was analyzed by flow cytometry in freshly isolated peripheral blood mononuclear cells as well as afterin vitrostimulation with the quadrivalent HPV (type 6/11/16/18) vaccine. In addition, the regulatory function of ILT2 on cell proliferation and IFN-γ production was analyzed. We found a significant increase in the expression of ILT2 by NK and CD3+CD56+lymphocytes and monocytes after quadrivalent HPV (type 6/11/16/18) vaccine immunization. In addition, thein vitrostimulation with the quadrivalent HPV (type 6/11/16/18) vaccine also increased the proportion of CD3−CD56+ILT2+NK cells. Although the inhibitory function of ILT2 on cell proliferation was enhanced after HPV immunization, thein vitroengagement of this receptor did not affect the synthesis of IFN-γ induced by HPV. Finally, a significant increase in the expression of NKG2D, NKp30, and NKp46 by NK and CD3+CD56+lymphocytes was detected after quadrivalent HPV (type 6/11/16/18) vaccine immunization. Our data indicate that HPV immunization is associated with significant changes in the expression and function of different innate immune receptors, including ILT2, which may participate in the protective effect of HPV vaccines.
Complete Genome Sequence of Rahnella aquatilis CIP 78.65
Authors: Martinez Robert J. , Bruce David , Detter Chris , Goodwin Lynne A. , Han James , Han Cliff S. , Held Brittany , Land Miriam L. , Mikhailova Natalia , Nolan Matt , Pennacchio Len , Pitluck Sam , Tapia Roxanne , Woyke Tanja , Sobecky Patricia A.
Published: May 2012

Rahnella aquatilis
CIP 78.65 is a gammaproteobacterium isolated from a drinking water source in Lille, France. Here we report the complete genome sequence of
Rahnella aquatilis
CIP 78.65, the type strain of
R. aquatilis
.
Genome Sequence of Xanthomonas citri pv. mangiferaeindicae Strain LMG 941
Authors: Midha Samriti , Ranjan Manish , Sharma Vikas , Pinnaka Anil Kumar , Patil Prabhu B.
Published: May 2012

We report the 5.1-Mb genome sequence of
Xanthomonas citri
pv. mangiferaeindicae strain LMG 941, the causal agent of bacterial black spot in mango. Apart from evolutionary studies, the draft genome will be a valuable resource for the epidemiological studies and quarantine of this phytopathogen.
Genome Sequences of the Ethanol-Tolerant Lactobacillus vini Strains LMG 23202
T
and JP7.8.9
Authors: Luckwu de Lucena Brígida Thaís , Silva Genivaldo G. Z. , Manoel dos Santos Billy , Dias Graciela M. , Amaral Gilda Rose S. , Moreira Ana Paula B. , de Morais Júnior Marcos Antônio , Dutilh Bas E. , Edwards Robert A. , Balbino Valdir , Thompson Cristiane C. , Thompson Fabiano L.
Published: May 2012

We report on the genome sequences of
Lactobacillus vini
type strain LMG 23202
T
(DSM 20605) (isolated from fermenting grape musts in Spain) and the industrial strain
L. vini
JP7.8.9 (isolated from a bioethanol plant in northeast Brazil). All contigs were assembled using gsAssembler, and genes were predicted and annotated using Rapid Annotation using Subsystem Technology (RAST). The identified genome sequence of LMG 23202
T
had 2.201.333 bp, 37.6% G+C, and 1,833 genes, whereas the identified genome sequence of JP7.8.9 had 2.301.037 bp, 37.8% G+C, and 1,739 genes. The gene repertoire of the species
L. vini
offers promising opportunities for biotechnological applications.
Genome Sequence of the Probiotic Bacterium Sporolactobacillus vineae SL153
T
Authors: Kim Dae-Soo , Sin Yeseul , Kim Dong-Wook , Paek Jayoung , Kim Ryong Nam , Jung Min Young , Park In-Soon , Kim Aeri , Kang Aram , Park Hong-Seog , Choi Sang-Haeng , Chang Young-Hyo
Published: May 2012

The novel
Sporolactobacillus vineae
SL153
T
strain has excellent intestinal adherence and growth inhibitory effect on pathogenic microorganisms, including
Vibrio
genus microorganisms, and therefore can be effectively used for the prevention and treatment of disease caused by pathogenic microorganisms. Here, we first report the draft genome sequence of a novel species in the genus
Sporolactobacillus
.
Microfluidic-Chip-Based Multiple-Locus Variable-Number Tandem-Repeat Fingerprinting with New Primer Sets for Methicillin-Resistant Staphylococcus aureus
Authors: Sabat Artur J. , Chlebowicz Monika A. , Grundmann Hajo , Arends Jan P. , Kampinga Greetje , Meessen Nico E. L. , Friedrich Alexander W. , van Dijl Jan Maarten
Published: May 2012

The detection of outbreaks of methicillin-resistant
Staphylococcus aureus
(MRSA) infections and a rapid and accurate identification of sources and routes of transmission should be conducted in hospital settings as early and swiftly as possible. In this study, we investigated the application potential of a new approach based on multiple-locus variable-number tandem-repeat fingerprinting (MLVF) and microfluidics technology for a rapid discrimination of MRSA lineages in outbreak settings. A total of 206 nonrepetitive MRSA isolates recovered from infected patients at the University Medical Center Groningen between 2000 and 2010 were tested. The results obtained by MLVF using microcapillary electrophoresis with newly designed primers were compared to those obtained by
spa
typing and multiple-locus variable-number tandem-repeat analysis (MLVA). The discriminatory power was 0.980 (107 patterns), 0.969 (85 allelic profiles), and 0.959 (66 types) for MLVF, MLVA, and
spa
typing, respectively. All methods tested showed a good concordance of results calculated by the adjusted Rand's coefficient method. Comparisons of data obtained by the three approaches allowed us to propose an 88% cutoff value for the similarity between any two MLVF patterns, which can be used in
S. aureus
epidemiological studies, including analyses of outbreaks and strain transmission events. Of the three tested methods, MLVF is the cheapest, fastest, and easiest to perform. MLVF applied to microfluidic polymer chips is a rapid, cheap, reproducible, and highly discriminating tool to determine the clonality of MRSA isolates and to trace the spread of MRSA strains over periods of many years. Although
spa
typing should be used due to its portability of data, MLVF has a high added value because it is more discriminatory.
Detection of a Knockdown Resistance Mutation Associated with Permethrin Resistance in the Body Louse Pediculus humanus corporis by Use of Melting Curve Analysis Genotyping
Authors: Drali Rezak , Benkouiten Samir , Badiaga Sékéné , Bitam Idir , Rolain Jean Marc , Brouqui Philippe
Published: May 2012

Louse-borne diseases are prevalent in the homeless, and body louse eradication has thus far been unsuccessful in this population. We aim to develop a rapid and robust genotyping method usable in large field-based clinical studies to monitor permethrin resistance in the human body louse
Pediculus humanus corporis
. We assessed a melting curve analysis genotyping method based on real-time PCR using hybridization probes to detect the M815I-T917I-L920F knockdown resistance (kdr) mutation in the paraorthologous voltage-sensitive sodium channel (VSSC) α subunit gene, which is associated with permethrin resistance. The 908-bp DNA fragment of the VSSC gene, encoding the α subunit of the sodium channel and encompassing the three mutation sites, was PCR sequenced from 65 lice collected from a homeless population. We noted a high prevalence of the 3 indicated mutations in the body lice collected from homeless people (100% for the M815I and L920F mutations and 56.73% for the T917I mutation). These results were confirmed by melting curve analysis genotyping, which had a calculated sensitivity of 100% for the M815I and T917I mutations and of 98% for the L920F mutation. The specificity was 100% for M815I and L920F and 96% for T917I. Melting curve analysis genotyping is a fast, sensitive, and specific tool that is fully compatible with the analysis of a large number of samples in epidemiological surveys, allowing the simultaneous genotyping of 96 samples in just over an hour (75 min). Thus, it is perfectly suited for the epidemiological monitoring of permethrin resistance in human body lice in large-scale clinical studies.
Enzootic Enteropathogenic Escherichia coli Infection in Laboratory Rabbits
Authors: Swennes Alton G. , Buckley Ellen M. , Parry Nicola M. A. , Madden Carolyn M. , García Alexis , Morgan Peter B. , Astrofsky Keith M. , Fox James G.
Published: May 2012

Enteropathogenic
Escherichia coli
(EPEC) is the most important cause of persistent diarrhea in children, particularly in developing countries. Animals serve as pathogenic
E. coli
reservoirs, and compelling evidence for cross-species EPEC transmission exists. In this report, enzootic EPEC infection associated with up to 10.5% diarrhea-associated morbidity in a large laboratory Dutch Belted rabbit colony was investigated. These rabbits were obtained from a commercial vendor and had acute diarrhea following shipment. Fecal culture of 20 rabbits yielded 48
E. coli
isolates, 83% of which were
eae
positive. Repetitive sequence-based PCR (REP-PCR) and serologic analysis identified a single disease-associated EPEC O145:H2 strain. In sampled rabbits, EPEC-positive culture and the presence of diarrhea were significantly associated. This strain displayed a localized adherence-like HEp-2 cell adherence pattern, as seen in diarrheic human infant EPEC isolates. Treatment was instituted with the fluoroquinolone antibiotic enrofloxacin, to which all isolates were susceptible. Preshipment parenteral enrofloxacin administration reduced diarrhea-associated morbidity 22-fold and mortality 12-fold in subsequent deliveries. This report emphasizes the zoonotic potential of animal EPEC strains and the need for virulence determinant-based screening of
E. coli
isolates from diarrheic animals.
Ebolavirus Requires Acid Sphingomyelinase Activity and Plasma Membrane Sphingomyelin for Infection
Authors: Miller Mary E. , Adhikary Shramika , Kolokoltsov Andrey A. , Davey Robert A.
Published: May 2012

Acid sphingomyelinase (ASMase) converts the lipid sphingomyelin (SM) to phosphocholine and ceramide and has optimum activity at acidic pH. Normally, ASMase is located in lysosomes and endosomes, but membrane damage or the interaction with some bacterial and viral pathogens can trigger its recruitment to the plasma membrane. Rhinovirus and measles viruses each require ASMase activity during early stages of infection. Both sphingomyelin and ceramide are important components of lipid rafts and are potent signaling molecules. Each plays roles in mediating macropinocytosis, which has been shown to be important for ebolavirus (EBOV) infection. Here, we investigated the role of ASMase and its substrate, SM, in EBOV infection. The work was performed at biosafety level 4 with wild-type virus with specificity and mechanistic analysis performed using virus pseudotypes and virus-like particles. We found that virus particles strongly associate with the SM-rich regions of the cell membrane and depletion of SM reduces EBOV infection. ASM-specific drugs and multiple small interfering RNAs strongly inhibit the infection by EBOV and EBOV glycoprotein pseudotyped viruses but not by the pseudotypes bearing the glycoprotein of vesicular stomatitis virus. Interestingly, the binding of virus-like particles to cells is strongly associated with surface-localized ASMase as well as SM-enriched sites. Our work suggests that ASMase activity and SM presence are necessary for efficient infection of cells by EBOV. The inhibition of this pathway may provide new avenues for drug treatment.
Porcine Reproductive and Respiratory Syndrome Virus Induces Interleukin-15 through the NF-κB Signaling Pathway
Authors: Fu Yi , Quan Rong , Zhang Hexiao , Hou Jun , Tang Jun , Feng Wen-hai
Published: May 2012

Porcine reproductive and respiratory syndrome virus (PRRSV) mainly infects macrophages/dendritic cells and modulates cytokine expression in these cells. Interleukin-15 (IL-15) is a pleiotropic cytokine involved in wide range of biological activities. It has been shown to be essential for the generation, activation, and proliferation of NK and NKT cells and for the survival and activation of CD8+effector and memory T cells. In this study, we discovered that PRRSV infection upregulated IL-15 production at both the mRNA and protein levels in porcine alveolar macrophages (PAMs), blood monocyte-derived macrophages (BMo), and monocyte-derived dendritic cells (DCs). We subsequently demonstrated that the NF-κB signaling pathway was essential for PRRSV infection-induced IL-15 production. First, addition of an NF-κB inhibitor drastically reduced PRRSV infection-induced IL-15 production. We then found that NF-κB was indeed activated upon PRRSV infection, as evidenced by IκB phosphorylation and degradation. Moreover, we revealed an NF-κB binding motif in the cloned porcine IL-15 (pIL-15) promoter, deletion of which abrogated the pIL-15 promoter activity in PRRSV-infected alveolar macrophages. In addition, we demonstrated that PRRSV nucleocapsid (N) protein had the ability to induce IL-15 production in porcine alveolar macrophage cell line CRL2843 by transient transfection, which was mediated by its multiple motifs, and it also activated NF-κB. These data indicated that PRRSV infection-induced IL-15 production was likely through PRRSV N protein-mediated NF-κB activation. Our findings provide new insights into the molecular mechanisms underling the IL-15 production induced by PRRSV infection.
The relationship between executive dysfunction and post-stroke mortality: a population-based cohort study
Authors: Wiberg Bernice , Kilander Lena , Sundström Johan , Byberg Liisa , Lind Lars
Published: May 2012

Objectives

To study the associations of pre-stroke cognitive performance with mortality after first-ever stroke or transient ischaemic attack (TIA).

Design

A prospective cohort study.

Setting and participants

In participants having first-ever stroke or TIA during up to 14 years of post-test follow-up (n=155), we investigated the associations of pre-stroke variables and cognitive test results with post-stroke survival. The study is based on those participants of the Uppsala Longitudinal Study of Adult Men who performed cognitive function tests at approximately age 70 (n=919).

Primary outcome measures

Mortality after first-ever stroke or TIA related to pre-stroke executive performance.

Results

Eighty-four (54%) of the first-ever stroke/TIA patients died under a median follow-up of 2.5 years after the event. In Cox proportional hazard analyses adjusting for age, education, social group and traditional stroke risk factors, poor performance in Trail Making Test (TMT)-A was related to mortality (HR 1.88 per SD, 95% CI 1.31 to 2.71, p=0.001). The risk of mortality was approximately threefold higher in the highest tertile compared with the lowest tertile (HR TMT-A= 2.90 per SD, 95% CI 1.24 to 6.77, p=0.014). A similar pattern was seen for TMT-B, but Mini-Mental State Examination results were not related to risk of post-stroke mortality.

Conclusion

Executive performance measured by TMT-A and -B before stroke was independently associated with long-term risk of mortality, after first-ever stroke or TIA in a population-based study of older men.
Meeting the needs of smallholders
Authors: Roberts Victoria
Published: May 2012

Smallholders often keep a range of species with very different needs, and have a responsibility to ensure the welfare of these animals. Victoria Roberts explains how veterinary surgeons can help this growing sector by providing a comprehensive farm health plan and offering guidance and support.
Mastitis control in robotic milking systems
Authors: Edmondson Peter
Published: May 2012

Robotic milking involves the use of automated systems to milk cows as and when they choose. While this has clear benefits in many cases, the use of robots for milking also has some specific disadvantages and does not always represent the best solution for every farm. This article reviews the pros and cons of robotic milking, and discusses its impact on mastitis and milk quality. In addition, it discusses other key factors that need to be considered when using robots or deciding whether to move to robotic milking.
Investigation and management of splenic disease in dogs
Authors: Hayes Graham , Ladlow Jane
Published: May 2012

Splenic disorders are a significant cause of morbidity and mortality in middle‐aged and older dogs, and a spectrum of presentations is possible, from chronic non‐specific clinical signs to a rapidly fatal haemoabdomen. Splenomegaly is commonly recognised during clinical examination or imaging in practice, but it can be difficult to decide whether the primary problem is within the spleen itself (eg, a focal mass, in which case a splenectomy is generally the treatment of choice) or whether the splenomegaly represents systemic disease (eg, a lymphoma or immune‐mediated haemolytic anaemia, in which case a biopsy may be useful but a splenectomy may be contraindicated). Splenic surgery requires an appreciation of the vascular anatomy, and adequate monitoring as well as supportive treatment may be critical to the outcome of surgery. This article discusses the anatomy of the spleen and how to investigate splenomegaly, as well as how to perform a (partial) splenectomy and the possible complications involved.
COMPACT CAPACITANCE MODEL FOR PRINTED THIN FILM TRANSISTORS WITH NON-IDEAL CONTACTS
Authors: BHALERAO SHANTANU , KOUDYMOV ALEXEY , SHUR MICHAEL , YTTERDAL TROND , JACKSON WARREN , TAUSSIG CARL
Published: May 2012

We report on a compact capacitance model that accurately describes both the gate length dependent and the gate length independent frequency dispersion observed in C-V curves for printed thin film transistors with non-ideal contacts. We also show that modeling the drain current with two adjacent subthreshold regions (instead of just one in the previous RPI TFT model) is needed to match the measured current-voltage characteristics. We show that Elmore model which accounts for channel length transit time is not sufficient for describing the frequency dispersion in C-V curves for printed TFTs and present the new Variable Dispersion Model (VDM). VDM reproduces the experimentally observed gate length independent dispersion arising due to the finite time of the electron exchange between the localized states in the mobility gap and the states above the mobility edge in amorphous semiconductors. The combined Elmore-VDM model has been implemented in AIM-Spice and showed good agreement with measured C-V data.
EFFECT OF PROCESS VARIATIONS ON AN OTFT COMPACT MODEL PARAMETERS
Authors: PICOS R. , GARCIA E. , ESTRADA M. , CERDEIRA A. , IÑIGUEZ B.
Published: May 2012

We have studied the effect of some of the possible deviations on the values of the extracted parameters of a specific OTFT model, considering OTFTs designed using P 3 HT as semiconductor layer, PMMA as insulator, bottom gate, and top gold contacts. Specifically, we have studied the influence of misposition or misalignment of the masks, the effect of imperfections of etching, and the effect of variations on the layer deposition process. These effects have been simulated using the Silvaco Athena software, and they have been modeled as horizontal shifts of the etching windows and variations of the layers thickness. Once the devices were defined, they were simulated using Silvaco Atlas, and parameter extraction was performed using a specifically developed algorithm. We have found a strong correlation among some of the physical parameters and the model parameters that may offer useful insight for process optimization. Moreover, strong correlations have been found also among the model parameters. We have used these results to develop a Monte Carlo model, suitable for statistical circuit simulation.
DE SITTER MUSINGS
Authors: ANNINOS DIONYSIOS
Published: May 2012

We discuss some of the issues arising when considering asymptotically de Sitter space–times and attempts to address them. Our development begins at the classical level where several initial value problems are discussed and ends with several proposals for holography in asymptotically de Sitter space–times. Throughout the paper we give a review of some basic notions such as the geometry of Schwarzschild–de Sitter black hole, the Nariai limit and quantum field theory in a fixed de Sitter background. We also briefly discuss some semiclassical aspects such as the nucleation of black holes and the Hartle–Hawking wavefunctional. We end by giving an overview of some open questions. An emphasis is placed on the differences between a static patch observer confined to live in a thermal cavity and the metaobserver who has access to a finite region of the future boundary.
RG FLOW OF TRANSPORT QUANTITIES
Authors: LEE BUM-HOON , PAL SHESANSU SEKHAR , SIN SANG-JIN
Published: May 2012

The RG flow equation of various transport quantities are studied in arbitrary space–time dimensions, in the fixed as well as fluctuating background geometry both for the Maxwellian and DBI type of actions. The regularity condition on the flow equation of the conductivity at the horizon for the DBI action reproduces naturally the leading order result of Hartnoll et al. [J. High Energy Phys. 04, 120 (2010)]. Motivated by the result of van der Marel et al. [Science 425, 271 (2003], we studied, analytically, the conductivity versus frequency plane by dividing it into three distinct parts: ω < T, ω > T and ω ≫ T. In order to compare, we choose (3+1)-dimensional bulk space–time for the computation of the conductivity. In the ω < T range, the conductivity does not show up the Drude like form in any space–time dimensions. In the ω > T range and staying away from the horizon, for the DBI action with unit dynamical exponent, nonzero magnetic field and charge density, the conductivity goes as ω-2/3, whereas the phase of the conductivity, goes as, arctan ( Im σxx/ Re σxx) = π/6 and arctan ( Im σxy/ Re σxy) = -π/3. There exists a universal quantity at the horizon that is the phase angle of conductivity, which either vanishes or an integral multiple of π. Furthermore, we calculate the temperature dependence to the thermoelectric and the thermal conductivity at the horizon. The charge diffusion constant for the DBI action is studied.
REVISITING (QUASI-)EXACTLY SOLVABLE RATIONAL EXTENSIONS OF THE MORSE POTENTIAL
Authors: QUESNE C.
Published: May 2012

The construction of rationally-extended Morse potentials is analyzed in the framework of first-order supersymmetric quantum mechanics. The known family of extended potentials VA, B, ext (x), obtained from a conventional Morse potential VA-1, B(x) by the addition of a bound state below the spectrum of the latter, is reobtained. More importantly, the existence of another family of extended potentials, strictly isospectral to VA+1, B(x), is pointed out for a well-chosen range of parameter values. Although not shape invariant, such extended potentials exhibit a kind of "enlarged" shape invariance property, in the sense that their partner, obtained by translating both the parameter A and the degree m of the polynomial arising in the denominator, belongs to the same family of extended potentials. The point canonical transformation connecting the radial oscillator to the Morse potential is also applied to exactly solvable rationally-extended radial oscillator potentials to build quasi-exactly solvable rationally-extended Morse ones.
A MEMBERSHIP FUNCTION APPROACH FOR COST-RELIABILITY TRADE-OFF OF COTS SELECTION IN FUZZY ENVIRONMENT
Authors: GUPTA PANKAJ , VERMA SHILPI , MEHLAWAT MUKESH KUMAR
Published: May 2012

The optimization techniques used in commercial-off-the-shelf (COTS) selection process faces challenges to deal with uncertainty in many important selection parameters, for example, cost, reliability and delivery time. In this paper, we propose a fuzzy optimization model for selecting the best COTS product among the available alternatives for each module in the development of modular software systems. The proposed model minimizes the total cost of the software system satisfying the constraints of minimum threshold on system reliability, maximum threshold on the delivery time of the software, and incompatibility among COTS products. In order to deal with uncertainty in real-world applications of COTS selection, the coefficients of the cost objective function, delivery time constraints and minimum threshold on reliability are considered fuzzy numbers. The fuzzy optimization model is converted into a pair of mathematical programming problems parameterized by possibility (feasibility) level α using Zadeh's extension principle. The solutions of the resultant problems at different α-cuts provide lower and upper bounds of the fuzzy minimum total cost which helps in constructing the membership function of the cost objective function. The solution approach provide fuzzy solutions instead of a single crisp solution thereby giving decision maker enough flexibility in maintaining cost-reliability trade-off of COTS selection besides meeting other important system requirements. A real-world case study is discussed to demonstrate the effectiveness of the proposed model in fuzzy environment.
AXIVERSE AND BLACK HOLE
Authors: KODAMA HIDEO , YOSHINO HIROTAKA
Published: May 2012

String theory/M-theory general predicts that axionic fields with a broad mass spectrum extending below 10-10eV are produced after compactification to four dimensions. These axions/fields provoke a rich variety of cosmophysical phenomena on different scales depending on their masses and provide us new windows to probe the ultimate theory. In this article, after overviewing this axiverse idea1, I take up the black hole instability as the most fascinating one among such axionic phenomena and explain its physical mechanism and astrophysical predictions.
QUANTUM SPRING
Authors: FENG CHAO-JUN , LI XIN-ZHOU
Published: May 2012

In this paper, we will give a short review on quantum spring, which is a Casimir effect from the helix boundary condition that proposed in our earlier works. The Casimir force parallel to the axis of the helix behaves very much like the force on a spring that obeys the Hooke's law when the ratio r of the pitch to the circumference of the helix is small, but in this case, the force comes from a quantum effect, so we would like to call it quantum spring. On the other hand, the force perpendicular to the axis decreases monotonously with the increasing of the ratio r. Both forces are attractive and their behaviors are the same in two and three dimensions.
DARK ENERGY AND QCD GHOST
Authors: OHTA NOBUYOSHI
Published: May 2012

We argue that the dark energy that explains the observed accelerating expansion of the universe may arise due to the contribution to the vacuum energy of the QCD ghost in a time-dependent background. We show that the QCD ghost produces dark energy proportional to the Hubble parameter [Formula: see text] (ΛQCD is the QCD mass scale) which has the right magnitude ~ (3 × 10-3 eV)4.
Oxygen isotope variability in conodonts: implications for reconstructing Palaeozoic palaeoclimates and palaeoceanography
Authors: Wheeley James R. , Smith M. Paul , Boomer Ian
Published: May 2012

Conodonts have the potential to elucidate the intricacies of Palaeozoic climates, especially if δ
18
O values of single apatitic tooth-like ‘elements’ can be used to map evolving sea surface temperatures and differentiate oceanic water masses. Their ecological distribution as pelagic and nektobenthic organisms, high-resolution biostratigraphy, and abundance in Cambrian–Triassic rocks qualifies them as potentially robust climate archives. Previous ion microprobe conodont δ
18
O studies have proceeded directly to palaeotemperature interpretation without appreciation of inter- and intra-element variability or post-mortem artefacts. Here, ion microprobe analyses of Ordovician and Silurian conodonts establishes that: intra-element crown tissue δ
18
O typically varies by ≤1‰ (53% of conodonts analysed), is normally ≤2‰ (92% of analyses), and rarely varies by 2–4‰; δ
18
O can vary across elements, suggesting a microstructural and/or diagenetic control; δ
18
O can vary between species representatives by
c
. 3‰; δ
18
O of pelagic and nektobenthic taxa can be offset by 2–3‰; elements processed with formic acid have highly variable δ
18
O; and thermal alteration does affect δ
18
O. Conodont ion microprobe δ
18
O values are comparable with those of bulk methods, but utilization of material with no consideration of geological context or processing history may introduce significant artefacts. A protocol for future conodont oxygen isotope ion microprobe studies is proposed.

Supplementary material:

Full results of oxygen isotope analyses reported in this paper are available at
www.geolsoc.org.uk/SUP18516
.
Key factors controlling massive graphite deposition in volcanic settings: an example of a self-organized critical system
Authors: Luque F. J. , Ortega L. , Barrenechea J. F. , Huizenga J.-M. , Millward D.
Published: May 2012

Massive graphite deposition resulting in volumetrically large occurrences in volcanic environments is usually hindered by the low carbon contents of magmas and by the degassing processes occurring during and after magma emplacement. In spite of this, two graphite deposits are known worldwide associated with volcanic settings, at Borrowdale, UK, and Huelma, Spain. As inferred from the Borrowdale deposit, graphite mineralization resulted from the complex interaction of several factors, so it can be considered as an example of self-organized critical systems. These factors, in turn, could be used as potential guides for exploration. The key factors influencing graphite mineralization in volcanic settings are as follows: (1) an unusually high carbon content of the magmas, as a result of the assimilation of carbonaceous metasedimentary rocks; (2) the absence of significant degassing, related to the presence of sub-volcanic rocks or hypabyssal intrusions, acting as barriers to flow; (3) the exsolution of a carbon-bearing aqueous fluid phase; (4) the local structural heterogeneity (represented at Borrowdale by the deep-seated Burtness Comb Fault); (5) the structural control on the deposits, implying an overpressured, fluid-rich regime favouring a focused fluid flow; (6) the temperature changes associated with fluid flow and hydration reactions, resulting in carbon supersaturation in the fluid, and leading to disequilibrium in the system. This disequilibrium is regarded as the driving force for massive graphite precipitation through irreversible mass-transfer reactions. Therefore, the formation of volcanic-hosted graphite deposits can be explained in terms of a self-organized critical system.
Middle Triassic arc magmatism along the northeastern margin of the Tibet: U–Pb and Lu–Hf zircon characterization of the Gangcha complex in the West Qinling terrane, central China
Authors: Guo Xianqing , Yan Zhen , Wang Zongqi , Wang Tao , Hou Kejun , Fu Changlei , Li Jiliang
Published: May 2012

The tectonic setting of Mesozoic magmatic complexes in the northeastern margin of the Tibet plateau is disputed, and hence gives rise to uncertainty concerning the tectonic evolution of the northeastern Tibet Plateau and the timing of the closure of the Palaeo-Tethys ocean. The Gangcha complex is typical of these complexes, consisting of andesite, dacite, gabbro, gabbroic diorite, granodiorite, quartz diorite, and diorite with typical chemical traits of continental margin arc rocks. Andesite, gabbroic diorite, and mineralization-associated potassic-altered diorite yield weighted mean
206
Pb/
238
U ages of 242.1 ± 1.2 Ma, 243.8 ± 1.0 Ma and 234.0 ± 0.6 Ma respectively. Zircon ϵ
Hf
(t) for magmatic grains ranges from −3.5 to +5.7, interpreted to demonstrate that the Gangcha complex contains crustally contaminated mantle magmas. Inherited zircons in the complex yield similar U–Pb ages (777–310 Ma) to the A’nyemaqen composite ophiolite assemblage with ϵ
Hf
(t) of −17.4 to +11.6. This suggests that components of this older ophiolite melted and contributed to the Gangcha complex magmas. Hence the Gangcha complex is considered to have formed as a continental margin arc in northeastern Tibet by northward subduction during consumption of the Palaeo-Tethys ocean. Regionally, it corresponds to the arc magmatism along the eastern and western Kunlun sutures to the west and the Mianlue suture to the east.

Supplementary material:

Geochemical data, and zircon U–Pb and Lu–Hf data for the Gangcha complex are available at
www.geolsoc.org.uk/SUP18521
.
Forcing Stem Cells to Behave: A Biophysical Perspective of the Cellular Microenvironment
Authors: Sun Yubing , Chen Christopher S. , Fu Jianping
Published: May 2012

Physical factors in the local cellular microenvironment, including cell shape and geometry, matrix mechanics, external mechanical forces, and nanotopographical features of the extracellular matrix, can all have strong influences on regulating stem cell fate. Stem cells sense and respond to these insoluble biophysical signals through integrin-mediated adhesions and the force balance between intracellular cytoskeletal contractility and the resistant forces originated from the extracellular matrix. Importantly, these mechanotransduction processes can couple with many other potent growth-factor-mediated signaling pathways to regulate stem cell fate. Different bioengineering tools and microscale/nanoscale devices have been successfully developed to engineer the physical aspects of the cellular microenvironment for stem cells, and these tools and devices have proven extremely powerful for identifying the extrinsic physical factors and their downstream intracellular signaling pathways that control stem cell functions.
Radical Use of Rossmann and TIM Barrel Architectures for Controlling Coenzyme B12Chemistry
Authors: Dowling Daniel P. , Croft Anna K. , Drennan Catherine L.
Published: May 2012

The ability of enzymes to harness free-radical chemistry allows for some of the most amazing transformations in nature, including reduction of ribonucleotides and carbon skeleton rearrangements. Enzyme cofactors involved in this chemistry can be large and complex, such as adenosylcobalamin (coenzyme B12), simpler, such as S-adenosylmethionine and an iron-sulfur cluster (i.e., poor man's B12), or very small, such as one nonheme iron atom coordinated by protein ligands. Although the chemistry catalyzed by these enzyme-bound cofactors is unparalleled, it does come at a price. The enzyme must be able to control these radical reactions, preventing unwanted chemistry and protecting the enzyme active site from damage. Here, we consider a set of radical folds: the (β/α)8or TIM barrel, combined with a Rossmann domain for coenzyme B12-dependent chemistry. Using specific enzyme examples, we consider how nature employs the common TIM barrel fold and its Rossmann domain partner for radical-based chemistry.
Functional Architecture of the Nuclear Pore Complex
Authors: Grossman Einat , Medalia Ohad , Zwerger Monika
Published: May 2012

The nuclear pore complex (NPC) is the sole gateway between the nucleus and the cytoplasm. NPCs fuse the inner and outer nuclear membranes to form aqueous translocation channels that allow the free diffusion of small molecules and ions, as well as receptor-mediated transport of large macromolecules. The NPC regulates nucleocytoplasmic transport of macromolecules, utilizing soluble receptors that identify and present cargo to the NPC, in a highly selective manner to maintain cellular functions. The NPC is composed of multiple copies of approximately 30 different proteins, termed nucleoporins, which assemble to form one of the largest multiprotein assemblies in the cell. In this review, we address structural and functional aspects of this fundamental cellular machinery.
Prokaryotic Diacylglycerol Kinase and Undecaprenol Kinase
Authors: Van Horn Wade D. , Sanders Charles R.
Published: May 2012

Prokaryotic diacylglycerol kinase (DAGK) and undecaprenol kinase (UDPK) are the lone members of a family of multispan membrane enzymes that are very small, lack relationships to any other family of proteins—including water soluble kinases—and exhibit an unusual structure and active site architecture. Escherichia coli DAGK plays an important role in recycling diacylglycerol produced as a by-product of biosynthesis of molecules located in the periplasmic space. UDPK seems to play an analogous role in gram-positive bacteria, where its importance is evident because UDPK is essential for biofilm formation by the oral pathogen Streptococcus mutans. DAGK has also long served as a model system for studies of membrane protein biocatalysis, folding, stability, and structure. This review explores our current understanding of the microbial physiology, enzymology, structural biology, and folding of the prokaryotic DAGK family, which is based on over 40 years of studies.
Bacterial Mechanosensitive Channels—MscS: Evolution's Solution to Creating Sensitivity in Function
Authors: Naismith James H. , Booth Ian R.
Published: May 2012

The discovery of mechanosensing channels has changed our understanding of bacterial physiology. The mechanosensitive channel of small conductance (MscS) is perhaps the most intensively studied of these channels. MscS has at least two states: closed, which does not allow solutes to exit the cytoplasm, and open, which allows rapid efflux of solvent and solutes. The ability to appropriately open or close the channel (gating) is critical to bacterial survival. We briefly review the science that led to the isolation and identification of MscS. We concentrate on the structure-function relationship of the channel, in particular the structural and biochemical approaches to understanding channel gating. We highlight the troubling discrepancies between the various models developed to understand MscS gating.
Hurdle Technology in Fruit Processing
Authors: Gómez Paula Luisina , Welti-Chanes Jorge , Alzamora Stella Maris
Published: May 2012

Conventional preservation technologies such as thermal processing ensure the safety and shelf life of fruit-derived products but can result in the loss of physicochemical and nutritional quality attributes. This review examines innovative hurdle techniques to obtain novel fruit products with fresh-like characteristics. The multifactorial processes were based on emerging preservation factors in combination or combining emerging factors with traditional ones. Selected practical examples of fruit processing using UV light, pulsed light (PL), ultrasound (US), and high hydrostatic pressure (HHP) are presented. Some issues of key importance for the design of combination processes are also addressed.
Minimization of Salmonella Contamination on Raw Poultry
Authors: Cox N.A. , Cason J.A. , Richardson L.J.
Published: May 2012

Many reviews have discussed Salmonella in poultry and suggested best practices to minimize this organism on raw poultry meat. Despite years of research and conscientious control efforts by industry and regulatory agencies, human salmonellosis rates have declined only modestly and Salmonella is still found on raw poultry. Expert committees have repeatedly emphasized the importance of controlling risk, but information about Salmonella in poultry is often limited to prevalence, with inadequate information about testing methods or strains of Salmonella that are detected by these methods and no information about any impact on the degree of risk. This review examines some assumptions behind the discussion of Salmonella in poultry: the relationships between sampling and cultural methodology, prevalence and numbers of cells, and the implications of serotype and subtype issues. Minimizing Salmonella contamination of poultry is not likely to reduce human salmonellosis acquired from exposure to contaminated chicken until these issues are confronted more systematically.
Molecular Design of Seed Storage Proteins for Enhanced Food Physicochemical Properties
Authors: Tandang-Silvas Mary Rose G. , Tecson-Mendoza Evelyn Mae , Mikami Bunzo , Utsumi Shigeru , Maruyama Nobuyuki
Published: May 2012

Seed storage proteins such as soybean globulins have been nutritionally and functionally valuable in the food industry. Protein structure-function studies are valuable in modifying proteins for enhanced functionality. Recombinant technology and protein engineering are two of the tools in biotechnology that have been used in producing soybean proteins with better gelling property, solubility, and emulsifying ability. This article reviews the molecular basis for the logical and precise protein designs that are important in obtaining the desired improved physicochemical properties.
New Developments and Applications of Bacteriocins and Peptides in Foods
Authors: Mills S. , Stanton C. , Hill C. , Ross R.P.
Published: May 2012

There is an increased desire for sophisticated foods, whereby consumers harbor higher expectations of health-promoting benefits above basic nutrition. Moreover, there is a move from the adulteration of foods with chemical preservatives toward biopreservation. Such expectations have led scientists to identify novel approaches to satisfy both demands, which utilize bacteriocin and peptide-based solutions. The best known examples of biopreservation involve bacteriocins. However, with the exception of nisin, bacteriocins have received limited use in the food industry. Peptides can be added to foods to improve consumer health. Some of the best known examples are angiotensin I–converting enzyme (ACE)-inhibitory peptides, which inhibit ACE, a key enzyme involved in blood pressure (BP) regulation. To be effective, these peptides must be bioavailable, but by their nature, peptides are degraded by digestion with proteolytic enzymes. This review critically discusses the use and potential of peptides and bacteriocins in food systems in terms of safety, quality, and improvement of human health.
Influence of Formulation and Processing on Absorption and Metabolism of Flavan-3-Ols from Tea and Cocoa
Authors: Neilson Andrew P. , Ferruzzi Mario G.
Published: May 2012

Flavan-3-ols are a major subclass of the class of plant phytochemicals known as flavonoids. Flavan-3-ols are commonly found in fruit, vegetable, and botanical products, including tea, cocoa, grapes, and apples. Both monomeric catechins and polymeric procyanidins are common in the diet, along with several derivatives produced by degradation of these species during processing. Both epidemiological and biological evidence suggests a health-protective role for dietary flavan-3-ols, leading to increased interest in the bioavailability of these compounds from foods. Flavan-3-ol bioavailability depends on numerous factors, including digestive release, absorption, metabolism, and elimination. In addition to these in vivo factors, the complexity of whole-food systems (physical form, flavan-3-ol form and dose, macronutrient and micronutrient profile, processing, etc.) influences the absorption efficiency and circulating profile of flavan-3-ols. An understanding of how food matrices may influence flavan-3-ol absorption will provide a framework to design and develop functional products that positively affect flavan-3-ol absorption and, by extension, potential bioactivity.
Dairy Products in the Food Chain: Their Impact on Health
Authors: Kliem Kirsty E. , Givens D.I.
Published: May 2012

Milk is a complex and complete food containing an array of essential nutrients that contribute toward a healthy, balanced diet. Numerous epidemiological studies have revealed that high consumption of milk and dairy products may have protective effects against coronary heart disease (CHD), stroke, diabetes, certain cancers (such as colorectal and bladder cancers), and dementia, although the mechanisms of action are unclear. Despite this epidemiological evidence, milk fatty acid profiles often lead to a negative perception of milk and dairy products. However, altering the fatty acid profile of milk by changing the dairy cow diet is a successful strategy, and intervention studies have shown that this approach may lead to further benefits of milk/dairy consumption. Overall, evidence suggests individuals who consume a greater amount of milk and dairy products have a slightly better health advantage than those who do not consume milk and dairy products.
Acrylamide in Foods: A Review of the Science and Future Considerations
Authors: Lineback David R. , Coughlin James R. , Stadler Richard H.
Published: May 2012

Acrylamide occurs in foods commonly consumed in diets worldwide. It is formed from the reaction of reducing sugars (e.g., glucose or fructose) with the amino acid asparagine via the Maillard reaction, which occurs during heat processing of foods, primarily those derived from plant origin, such as potato and cereal products, above 120°C (248°F). The majority of epidemiological studies concerning potential relationships between acrylamide consumption and different types of cancer have indicated no increased risk, except with a few types that warrant further study. Efforts to reduce the formation of acrylamide in food products have resulted in some successes, but there is no common approach that works for all foods. Reduction in some foods is probably not possible. The results from a major toxicological study (aqueous intake of acrylamide by rats and mice) are in the process of being released. The status of current knowledge in these areas is reviewed.