bluuebunny/crossref_metadata_2025 huggingface dataset:
Aiming drug discovery at lysophosphatidic acid targets
Authors: Tigyi Gabor
Published: May 2010

Lysophosphatidic acid (LPA, 1‐radyl‐2‐hydroxy‐sn‐glycero‐3‐phosphate) is the prototype member of a family of lipid mediators and second messengers. LPA and its naturally occurring analogues interact with G protein‐coupled receptors on the cell surface and a nuclear hormone receptor within the cell. In addition, there are several enzymes that utilize LPA as a substrate or generate it as a product and are under its regulatory control. LPA is present in biological fluids, and attempts have been made to link changes in its concentration and molecular composition to specific disease conditions. Through their many targets, members of the LPA family regulate cell survival, apoptosis, motility, shape, differentiation, gene transcription, malignant transformation and more. The present review depicts arbitrary aspects of the physiological and pathophysiological actions of LPA and attempts to link them with select targets. Many of us are now convinced that therapies targeting LPA biosynthesis and signalling are feasible for the treatment of devastating human diseases such as cancer, fibrosis and degenerative conditions. However, successful targeting of the pathways associated with this pleiotropic lipid will depend on the future development of as yet undeveloped pharmacons.
Share the Fame or Share the Blame? The Reputational Implications of Partnerships
Authors: Costa Luís Almeida , Vasconcelos Luís
Published: May 2010

We use an adverse selection model to study the dynamics of firms' reputations when firms implement joint projects. We show that in the case of joint projects a firm's reputation does not necessarily increase following a success and does not necessarily decrease following a failure. We also study how reputation considerations affect firms' decisions to participate in joint projects. We show that a high‐reputation partner is not necessarily preferable to a low‐reputation partner and, when implementation of the joint project by a single firm is possible, a high‐quality partner may not be preferable to a low‐quality partner.
Peer‐to‐Peer File Sharing and the Market for Digital Information Goods
Authors: Casadesus‐Masanell Ramon , Hervas‐Drane Andres
Published: May 2010

We study competitive interaction between two alternative models of digital content distribution over the Internet: peer‐to‐peer (p2p) file sharing and centralized client–server distribution. We present microfoundations for a stylized model of p2p file sharing where all peers are endowed with standard preferences and show that the endogenous structure of the network is conducive to sharing by a significant number of peers, even if sharing is costlier than freeriding. We build on this model of p2p to analyze the optimal strategy of a profit‐maximizing firm, such as Apple, that offers content available at positive prices. We characterize the size of the p2p network as a function of the firm's pricing strategy, and show that the firm may be better off setting high prices, allowing the network to survive, and that the p2p network may work more efficiently in the presence of the firm than in its absence.
Customer Information Sharing: Strategic Incentives and New Implications
Authors: Kim Byung‐Cheol , Choi Jay Pil
Published: May 2010

We study oligopolistic firms' incentives to share customer information about past purchase history when firms are uncertain about whether a particular consumer considers the product offerings as complements or substitutes. We show that both the incentive to share customer information and its effects on consumers depend crucially on the relative magnitudes of the prices that would prevail in the complementary and substitute markets if consumers were fully segmented according to their preferences. This paper has important implications for merger analysis when the primary motive for merger is the acquisition of another firm's customer lists. Our analysis also suggests a new role of middlemen as information aggregators.
Competition Among Health Plans: A Two‐Sided Market Approach
Authors: Bardey David , Rochet Jean‐Charles
Published: May 2010

We set up a two‐sided market framework to model competition between a Prefered Provider Organization (PPO) and a Health Maintenance Organization (HMO). Both health plans compete to attract policyholders on one side and providers on the other. The PPO, which is characterized by a higher diversity of providers, attracts riskier policyholders. Our two‐sided framework allows us to examine the consequences of this risk segmentation on the providers' side, especially in terms of remuneration. The outcome of the competition depends mainly on two effects: a demand effect, influenced by the value put by policyholders on the providers access and an adverse selection effect, captured by the characteristics of the health risk distribution. If the adverse selection effect is too strong, the HMO receives a higher profit in equilibrium. On the contrary, if the demand effect dominates, the PPO profit is higher in spite of the unfavorable risk segmentation. We believe that by highlighting the two‐sided market structure of the health plans' competition, our model provides a new insight to understand the increase in the PPOs' market share as observed in the USA during the last decade.
Closed‐Form Solutions to Bundling Problems
Authors: Eckalbar John C.
Published: May 2010

This paper investigates the case of a monopolist selling two distinct goods to a group of m traders who are characterized by their reservation prices, which are drawn independently from uniform distributions over the intervals [ 0, R1] and [ 0, R2]. Closed‐form solutions are derived for optimal prices, quantities, profits, and consumers' surplus under situations of separate sales, pure bundling, and mixed bundling. This allows a clear comparison of the price, output, and welfare effects of various forms of bundling. We further investigate situations of positive marginal cost, positive and negative correlation of reservation values, and substitutes and complements.
La métropolisation à l’aune de la ‘loi’ taille/rang : Le cas Canadien, 1971–2001
Authors: LALANNE AURÉLIE , SHEARMUR RICHARD
Published: May 2010

Le processus de métropolisation attire actuellement beaucoup d’attention. Une des conséquences de ce processus, observé par de nombreux chercheurs, est la croissance plus lente, voire le déclin, de villes petites et moyennes. D’un point de vue théorique, ceci est compatible avec les théories de la croissance endogène : les métropoles offrent aux acteurs économiques des facteurs clés (accès à l’information, aux réseaux globaux…) qui sont absents des villes de taille plus modeste. Cependant, il y aussi, actuellement, une résurgence d’intérêt pour la loi de Zipf, et, plus généralement, pour la grande stabilité que l’on observe dans la distribution par taille des villes. Ces deux corpus semblent être en contradiction. Or, à partir de données canadiennes couvrant la période 1971 à 2001 nous montrons que même si la métropolisation semble effectivement avoir lieu, ceci n’est pas nécessairement incompatible avec une distribution stable des tailles de ville. En effet, si l’on suppose que la loi de Zipf est applicable aux systèmes urbains dans des contextes socio‐économiques stables, alors la métropolisation que l’on observe actuellement ne pourrait être qu’un ajustement du système urbain aux nouvelles réalités sociales et économiques qui opèrent depuis la fin des années 1970. Ce réajustement mènera peut‐être à une nouvelle hiérarchie urbaine qui reflétera de nouveau les régularités de Zipf.
The association of metabolic syndrome with periodontal disease is confounded by age and smoking in a Korean population: the Shiwha–Banwol Environmental Health Study
Authors: Han Dong‐Hun , Lim Sin‐Ye , Sun Bo‐Cheng , Paek Domyung , Kim Hyun‐Duck
Published: May 2010

Han D‐H, Lim S‐Y, Sun B‐C, Paek D, Kim H‐D. The association of metabolic syndrome with periodontal disease is confounded by age and smoking in a Korean population: the Shiwha–Banwol Environmental Health Study. J Clin Periodontol 2010; 37: 609–616. doi: 10.1111/j.1600‐051X.2010.01580.x.

Aim: Because metabolic syndrome (MS) is pro‐inflammatory and periodontitis is inflammatory, we issued the hypothesis that MS (the explanatory variable) is associated with periodontitis (the outcome variable). This study aimed to examine the link between MS and periodontitis among Koreans.

Materials and Methods: From the Shiwha–Banwol Environmental Health Study, 1046 subjects aged 18 years or older were cross‐sectionally surveyed. All participants underwent comprehensive dental and medical health examinations. The community periodontal index was used to assess periodontitis. Age, gender, monthly family income, smoking, drinking, frequency of daily teeth brushing, and physical activity were evaluated as confounders.

Results: MS was strongly associated with periodontitis [odds ratio (OR): 1.7, 95% confidence interval (CI): 1.22–2.37], and MS with more components had a higher association. The association was higher for elders aged 65 years or more, males, and smokers. MS including both high glucose and hypertension had a higher association with the OR of 2.19 (95% CI: 1.23–3.90) comparing with other types of MS.

Conclusions: Our results suggested that MS might be associated with periodontitis and the association was confounded by age, gender, and smoking. MS with high glucose and hypertension showed the higher impact on this link.
Haplotype‐dependent Differential Activation of the Human IL‐10 Gene Promoter in Macrophages and Trophoblasts: Implications for Placental IL‐10 Deficiency and Pregnancy Complications
Authors: Sharma Surendra , Stabila Joan , Pietras Linda , Singh Arvind R. , McGonnigal Bethany , Ernerudh Jan , Matthiesen Leif , Padbury James F.
Published: May 2010

Citation Sharma S, Stabila J, Pietras L, Singh AR, McGonnigal B, Ernerudh J, Matthiesen L, Padbury JF. Haplotype‐dependent differential activation of the human IL‐10 gene promoter in macrophages and trophoblasts: Implications for placental IL‐10 deficiency and pregnancy complications. Am J Reprod Immunol 2010; 64: 179–187

Problem  Polymorphic changes in the IL‐10 gene promoter have been identified that lead to altered IL‐10 production. We hypothesized that because of these genotypic changes, the IL‐10 promoter might be expressed in a cell type–specific manner and may respond differentially to inflammatory triggers.

Method of study  We created reporter gene promoter constructs containing GCC, ACC, and ATA haplotypes using DNA from patients harboring polymorphic changes at −1082 (G→A), −819 (C→T), and −592 (C→A) sites in the IL‐10 promoter. These individual luciferase reporter constructs were transiently transfected into either primary term trophoblasts or THP1 monocytic cells. DNA‐binding studies were performed to implicate the role of the Sp1 transcription factor in response to differential promoter activity.

Results  Our results suggest that the GCC promoter construct was activated in trophoblast cells in response to lipopolysaccharide (LPS), as demonstrated by reporter gene expression, but not in monocytic cells. The ACC construct showed weaker activation in both cell types. Importantly, while the ATA promoter was constitutively activated in both cell types, its expression was selectively repressed in response to LPS, but only in trophoblasts. DNA‐nuclear protein binding assays with nuclear extracts from LPS treated or untreated cells suggested a functional relevance for Sp1 binding differences at the −592 position.

Conclusions  These results demonstrate cell type–specific effects of the genotypic changes in the IL‐10 gene promoter. These responses may be further modulated by bacterial infections or other inflammatory conditions to suppress IL‐10 production in human trophoblasts.
Evaluation of HLA‐G5 Plasmatic Levels During Pregnancy and Relationship with the 14‐bp Polymorphism
Authors: Gonzalez Alvaro , Alegre Estibaliz , Torres Maria I. , Díaz‐Lagares Angel , Lorite Pedro , Palomeque Teresa , Arroyo Ainhoa
Published: May 2010

Citation Gonzalez A, Alegre E, Torres MI, Díaz‐Lagares A, Lorite P, Palomeque T, Arroyo A. Evaluation of HLA‐G5 plasmatic levels during pregnancy and relationship with the 14‐bp polymorphism. Am J Reprod Immunol 2010

Problem  Plasmatic HLA‐G levels increase during pregnancy, but the contribution of each different isoform has not been elucidated yet.

Method of study  HLA‐G5 was analyzed by ELISA in 19 controls, 79 women in the first 8 weeks of pregnancy and in nine women monthly until delivery. Genotyping for the 14‐bp polymorphism was performed by PCR amplification of exon 8.

Results  HLA‐G5 was detected in plasma from 80% of pregnant women. The levels did not change during pregnancy, and there were no differences compared to control non‐pregnant women. There was a high interindividual variation that was maintained throughout the pregnancy. The presence of +14‐bp allele was associated with HLA‐G5 positivity. Pregnant women who were heterozygotic to 14‐bp polymorphism had significantly higher levels of HLA‐G5 compared to −14 bp/−14‐bp homozygotic.

Conclusion  Plasmatic HLA‐G5 levels do not change during pregnancy and its concentration depends on 14‐bp polymorphism.
Restoration of C4 grasses with seasonal fires in a C3/C4 grassland invaded by Prosopis glandulosa, a fire‐resistant shrub
Authors: Ansley R. James , Boutton Thomas W. , Mirik Mustafa , Castellano Michael J. , Kramp Betty A.
Published: May 2010

Questions: Can prescribed fire restore C4 perennial grasses in grassland ecosystems that have become dominated by fire‐resistant C3 shrubs (Prosopis glandulosa) and C3 grasses? Do fires in different seasons alter the direction of change in grass composition?

Location: Texas, USA.

Methods: We quantified short‐ and long‐term (12 yr post‐fire) herbaceous functional group cover and diversity responses to replicated seasonal fire treatments: (1) repeated‐winter fires (three in 5 yr), (2) repeated‐summer fires (two in 3 yr), and (3) alternate‐season fires (two winter and one summer in 4 yr), compared with a no‐fire control.

Results: Summer fires were more intense than winter fires, but all fire treatments temporarily decreased Prosopis and C3 annual grass cover. The alternate‐season fire treatment caused a long‐term increase in C4 mid‐grass cover and functional group diversity. The repeated‐summer fire treatment increased C4 short‐grass cover but also caused a long‐term increase in bare ground. The repeated winter fire treatment had no long‐term effects on perennial grass cover. Mesquite post‐fire regrowth had increasingly negative impacts on herbaceous cover in all fire treatments.

Conclusions: Summer fire was necessary to shift herbaceous composition toward C4 mid‐grasses. However, the repeated‐summer fire treatment may have been too extreme and caused post‐fire herbaceous composition to “over‐shift” toward less productive C4 short‐grasses rather than C4 mid‐grasses. This study provides some of the first long‐term data showing a possible benefit of mixing seasonal fires (i.e., the alternate‐season fire treatment) in a prescribed burning management plan to restore C4 mid‐grass cover and enhance overall herbaceous diversity.
The effects of urea‐treated potato pulp (PP) ensiled with beet pulp or wheat bran pellets to reduce moisture of PP and flake density of corn grain supplemented with the PP silage on digestibility and ruminal fermentation in beef steers
Authors: SUGIMOTO Masahito , SAITO Waka , OOI Motoki
Published: May 2010

The effects of adding beet pulp or wheat bran to urea‐treated potato pulp (PP) in order to reduce moisture of PP silage and flake density of corn grain on digestibility and ruminal fermentation in beef steers were studied in a split‐plot design experiment. The whole‐plot treatments were PP silage mixed with 0% added pellets (CON), 9% (as‐fed basis) beet pulp pellets (BP) or 9% (as‐fed basis) wheat bran pellets (WB) as water‐absorbing materials. The subplot treatments consisted of supplements formulated to contain either high‐density corn (HDC) or low‐density corn (LDC). BP steers consumed more (BP vs WB, P = 0.011) concentrate than did WB steers, whereas hay intake did not differ between the treatments. Dry matter (BP vs WB, P = 0.023) and organic matter (BP vs WB, P = 0.029) digestibility were higher for BP steers than for WB steers. Starch digestibility was higher (P = 0.006) for LDC than for HDC. There were no differences in the concentration of ruminal ammonia nitrogen among the treatments. Molar proportions of ruminal acetate were higher for BP steers than for WB steers (BP vs WB, P = 0.030). Conversely, molar proportions of propionate were lower for BP steers than for WB steers (BP vs WB, P = 0.044). Flake density of corn did not affect ruminal characteristics. In conclusion, from the viewpoint of feed intake and digestibility, BP is superior to WB as a moisture control material for urea‐treated PP silage, and flake density of corn supplemented with urea‐treated PP silage does not alter ruminal fermentation.
Accurate analysis of taurine, anserine, carnosine and free amino acids in a cattle muscle biopsy sample
Authors: IMANARI Mai , HIGUCHI Mikito , SHIBA Nobuya , WATANABE Akira
Published: May 2010

We have established an analysis method for some free amino acids (FAAs), as well as taurine (Tau), anserine (Ans) and carnosine (Car), in a fresh biopsy sample from cattle muscle. A series of model biopsy samples, corresponding to the mixtures of lean meat, fat and connective tissue, was prepared and showed high correlation coefficients between the compound concentration and the 3‐methylhistidine (3‐MeHis) content derived from hydrolysis of the biopsy sample (r = 0.74–0.95, P < 0.01). Interference from blood contamination could not be neglected, because the concentration of some FAAs in blood was comparable to that in muscle. However, it was possible to control the contamination of Tau, Ans, Car, glutamic acid, glutamine, asparatic acid and alanine to less than 5.0% when the blood contamination was controlled to less than 23%.These results suggest the necessity of measuring 3‐MeHis as an index of lean meat and hemoglobin as an index of blood contamination when compounds in muscle biopsy samples are evaluated. We have carried out a series of these analyses using one biopsy sample and reveal differences in Tau, Ans, Car and some FAAs in beef muscle after different feeding regimes.
Characteristics of PCR fragments amplified using five microsatellite markers for identifying the Nagoya breed
Authors: NAKAMURA Akihiro , NAGAO Kenji , WATANABE Hisako , KONDO Hajime
Published: May 2010

The Nagoya breed is a native chicken of Aichi Prefecture, Japan, a dual‐purpose breed for eggs and meat. A method for distinguishing the Nagoya breed from Aichi Prefecture from other chickens using five microsatellite markers (ABR0015, ABR0257, ABR0417, ABR0495 and ADL0262) has already been utilized in order to check the authenticity of Nagoya breed‐labeled chicken on the market. The present study was conducted to investigate nucleotide sequences and sizes of PCR fragments containing the five microsatellite regions for the Nagoya breed and to confirm that the genomic identification could continue to be applied in the future. The DNA sequencing of fragments containing the five markers showed that ABR0015, ABR0417 and ABR0495 had a single haplotype, ABR0257 had three haplotypes, and ADL0262 had two haplotypes, although all the markers exhibited one fixed fragment size each upon sequencing of the fragments and fragment analysis. The results of the fragment analysis of each marker using DNA samples of 28 Nagoya breed males (G0 generation) reared in 2000–2001 and 20 of their offspring males (G8) reared in 2008–2009 showed one fixed fragment size in both populations. Therefore, we confirmed that the five microsatellite markers are useful tools for accurately distinguishing the Nagoya breed from other chickens.
Stage‐specific effects of osmolarity of a culture medium on development of pig oocytes and miniature pig somatic cell nuclear transfer embryos activated by ultrasound treatment
Authors: MIZOBE Yamato , KURINO Saori , SATA Yoshiaki , MORI Hironori , YOSHIDA Mitsutoshi , MIYOSHI Kazuchika
Published: May 2010

Whether high osmolarity of a culture medium at the early culture stage affects the development of pig oocytes and miniature pig somatic cell nuclear transfer (SCNT) embryos activated by ultrasound was examined. When oocytes were cultured in modified porcine zygote medium‐3 (mPZM‐3) with increased NaCl to 138 mmol/L (mPZM‐3+NaCl; 326 mOsm) or 50 mmol/L sucrose (mPZM‐3+sucrose; 318 mOsm) for the first 2 days and then cultured in normal mPZM‐3 (273 mOsm) for 5 days, the cleavage and blastocyst formation rates were significantly (P < 0.05) higher than those of oocytes cultured in mPZM‐3 for 7 days. The cleavage and blastocyst formation rates of SCNT embryos cultured in mPZM‐3+NaCl for the first 2 days and then cultured in mPZM‐3 for 5 days were also significantly (P < 0.05) higher than those of embryos cultured in mPZM‐3 for 7 days. These results showed that the high osmolarity of a culture medium induced by increasing NaCl concentration during the first 2 days improves the development of pig oocytes and miniature pig SCNT embryos activated by ultrasound.
Breastfeeding Educational Interventions for Health Professionals: A Synthesis of Intervention Studies
Authors: Watkins Amanda L. , Dodgson Joan E.
Published: May 2010

PURPOSE.  The purpose of this synthesis was to review intervention studies that focused on increasing the breastfeeding knowledge, self‐confidence, and supportive behaviors of healthcare professionals.

DESIGN AND METHODS.  Fourteen articles were identified through database searches as the basis for this review.

RESULTS.  Breastfeeding education can be effective in increasing the knowledge and confidence of nurses. Duration and exclusivity rates for breastfeeding may also be improved.

PRACTICE IMPLICATIONS.  Improving nurses' knowledge of breastfeeding is a modifiable factor that is important in supporting a mother in her decision to breastfeed.
School Nurses in New Jersey: A Quantitative Inquiry on Roles and Responsibilities
Authors: Krause‐Parello Cheryl A. , Samms Kimika
Published: May 2010

PURPOSE.  This study examined types of chronic diseases present and nursing procedures administered in school, health promotion and disease prevention efforts, collaborative efforts, perception of school nursing activities, documentation media of school nursing activities, and student academic outcomes.

DESIGN AND METHODS.  A nonexperimental research design was employed. The sample (N= 63) was practicing school nurses in New Jersey public schools.

RESULTS.  The increased numbers of students with chronic illnesses in mainstream classrooms have increased the roles and responsibilities of school nurses.

PRACTICE IMPLICATIONS.  School nurses can use the findings as a framework to articulate their roles and responsibilities.
Microcosm Assessment of a DNA Probe Applied to Aerobic Degradation of cis‐1,2‐Dichloroethene by Polaromonas sp. Strain JS666
Authors: Giddings Cloelle G.S. , Jennings Laura K. , Gossett James M.
Published: May 2010

A molecular biological tool based on an organism‐specific DNA sequence does not necessarily indicate in situ activity but serves important functions of evaluating the potential for biodegradation and mapping the distribution of an organism. Currently, DNA‐based probes are accepted as evaluative tools for site assessment. However, these techniques are far from standardized, and information on precision is usually lacking. Here, we present the development and evaluation of a DNA probe for Polaromonas sp. strain JS666, a bacterium that couples growth to aerobic oxidation of cis‐1,2‐dichloroethene (cDCE), and is therefore a promising candidate for bioaugmentation at sites where cDCE has accumulated in aerobic zones. The DNA probe was used in conjunction with quantitative polymerase chain reaction to track the abundance of JS666 in microcosms. This series of studies has allowed explicit resolution of the accuracy and precision of the probe and its correlation with variations in microcosm performance. We determined that the method is sufficient to monitor distribution of JS666 at bioaugmented sites. We found within environmental, mixed cultures, that the DNA target does not persist long after cell death, demonstrating that positive result from the probe is a strong indicator that degradation can occur in suitable environmental conditions. Finally, in the absence of suspected predation, the probe accurately and precisely tracks growth. Collectively, the studies appear to validate the utility of the molecular probe for site assessment in a bioaugmentation context.
The Occurrence and Persistence of MTBE in Groundwater in Windham, Maine, USA
Authors: Peckenham John M.
Published: May 2010

A study was conducted from July 1998 through November 2007 on the occurrence and distribution of the fuel oxygenate methyl tert‐butyl ether (MTBE) in a large sand and gravel aquifer located in southern Maine. MTBE was detected in 44% of 129 water samples collected from monitoring wells in concentrations up to 38.7 µg/L (reporting limit = 0.1 µg/L). The number of wells with detectable quantities of MTBE declined slightly between 1999 and 2007, but in general MTBE persisted throughout the period of study. Overall, MTBE was detected more frequently in the shallow and more transmissive parts of the aquifer. There was a statistically significant difference (p < 0.001) for MTBE concentrations relative to nearby land uses. MTBE was detected in 83% of the samples collected from wells in low‐density residential areas, in 50% of samples from urban areas, and in 60% of samples from undeveloped areas. The concentrations of MTBE in the test wells were compared across the sample dates for trends and seven wells had a positive trend (Mann–Kendall statistic), but none was significant at p < 0.05. Nine wells had a negative trend, but only one was significant at p < 0.05. Three wells had no trend. The absence of strong or even consistent trends indicates that MTBE persists in shallow groundwater, even after gasoline formulations were changed to reduce or eliminate MTBE.
A Novel Function of MicroRNA Let‐7d in Regulation of Galectin‐3 Expression in Attention Deficit Hyperactivity Disorder Rat Brain
Authors: Wu Lihui , Zhao Qianlei , Zhu Xuchao , Peng Min , Jia Chenyou , Wu Wei , Zheng Jing , Wu Xing Zhong
Published: May 2010

In this study we investigated the locomotor activity and non‐selective attention in spontaneously hypertensive rats (SHR) with control Wistar–Kyoto (WKY) rats, which were employed as an attention deficit hyperactivity disorder (ADHD) model. In open‐field test and làt maze, SHR rats were found to be much more spontaneously active than WKY rats. As compared with WKY rats, a lower level of galectin‐3 was observed in SHR brain prefrontal cortex (PFC), which was the major affected brain area of ADHD. Through miRNA microarray screening, rno‐let‐7d was noted to be solely upregulated in SHR PFC. Interestingly, rno‐let‐7d had a binding site at galectin‐3 mRNA and was shown to regulate galectin‐3 3′ untranslated region (UTR) directly. Mutation of galectin‐3 3′UTR by one nucleotide of the seed sequence prevented rno‐let‐7d regulation of the 3′ UTR completely. Although rno‐let‐7d did not directly regulate tyrosine hydroxylase (TH) 3′UTR, the level of galectin‐3 was important for cAMP response element binding protein, the major transcript factor for TH gene. Either overexpression or downexpression of galectin‐3 could result in modulation of TH expression in both PC12H and PC12L cells. In conclusion, our data suggested a novel function of rno‐let‐7d in regulation of galectin‐3 and in ADHD development. Rno‐let‐7d, which is increased in the PFC of SHR brain, negatively regulated galectin‐3, which is coupled with TH expression regulation.
Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry for the identification of environmental organisms: the Planctomycetes paradigm
Authors: Cayrou Caroline , Raoult Didier , Drancourt Michel
Published: May 2010

We have developed a matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS)‐based identification technique for Planctomycetes organisms, which are used here as bacteria of suitable diversity at genus and species level for testing resolution of the method. Planctomyces maris ATCC 29201, Planctomyces brasiliensis ATCC 49424T, P. brasiliensis ATCC 49425, Planctomyces limnophilus ATCC 43296T, Blastopirellula marina ATCC 49069T, Rhodopirellula baltica DSM 10527T and Gemmata obscuriglobus DSM 5831T were cultured on half‐strength marine broth and agar, or alternatively on caulobacter broth and agar. The resulting pellets of organisms (liquid) or colonies (solid agar) were directly applied to a MALDI‐TOF plate. This yielded a reproducible, unique protein profiles comprising 23–39 peaks ranging in size from 2403 to 12 091 Da. These peaks were unambiguously distinguished from any of the 3038 bacterial spectra in the Brüker database. Matrix‐assisted laser desorption/ionization time‐of‐flight patterns were similar for isolates grown in solid and in liquid medium, albeit the patterns from solid growth were more easily interpretable. After the incorporation of the herein determined profiles into the Brüker database, Planctomycetes isolates were blindly identified within 10 min, with an identification score in the range of 1.8 to 2.3. Matrix‐assisted laser desorption/ionization time‐of‐flight‐based clustering of these Planctomycetes organisms was consistent with 16S rDNA‐based phylogeny. However, the incorporation of additional non‐Planctomycetes MALDI‐TOF profiles in the analysis resulted in inconsequential clustering. In conclusion, MALDI‐TOF protein profiling is a new approach for the rapid and accurate identification of cultured environmental organisms, as illustrated in this study through the analysis of Planctomycetes.
The evolution of animals and plants via symbiosis with microorganisms
Authors: Rosenberg Eugene , Sharon Gil , Atad Ilil , Zilber‐Rosenberg Ilana
Published: May 2010

Animals and plants evolved from prokaryotes and have remained in close association with them. We suggest that early eukaryotic cells, formed by the fusion of two or more prokaryotes, already contained prokaryotic genetic information for aggregation and the formation of multicellular structures. The hologenome theory of evolution posits that a unit of selection in evolution is the holobiont (host plus symbionts). The hologenome is defined as the genetic information of the host and its microbiota, which function in consortium. Genetic variation of the holobiont, the raw material for evolution, can arise from changes in either the host or the symbiotic microbiota genomes. Changes in the hologenome can occur by two processes that are specific to holobionts: microbial amplification and acquisition of novel strains from the environment. Recent data from culture‐independent studies provides considerable support of the hologenome theory: (i) all animals and plants contain abundant and diverse microbiota, (ii) the symbiotic microbiota affects the fitness of their host and (iii) symbiotic microorganisms are transmitted from parent to offspring. Consideration of the dynamic aspects of symbioses of hosts with their diverse microbiota leads to the conclusion that holobionts can evolve not only via Darwinian but also by adaptive Lamarckian principles.
The Association between Sub‐Therapeutic Antibiotics andSalmonellaTyphimurium in Market‐Weight Swine: A Systematic Review and Summation of Evidence from 1950 to 2007
Authors: Denagamage T. , O’Connor A. , Sargeant J. , McKean J.
Published: May 2010

A systematic review approach was used to evaluate the association between sub‐therapeutic antibiotics in feed andSalmonellaTyphimurium isolation in market‐weight finisher swine raised in modern swine production systems. Fourteen challenge trials described the efficacy of different antibiotics after challenge withS. Typhimurium. The studies identified were of limited evidentiary value for the review question because they were not relevant to the review question, i.e. conducted in artificial settings on small numbers of young pigs. None of the studies reported using blinding during outcome assessment. No antibiotic regimen was evaluated more than once. The association between sub‐therapeutic antibiotics andSalmonellaoutcomes in market‐weight swine raised in modern production systems cannot be summarized using the currently available literature. Many available studies fail to report critical study design features such as blinding and/or to take into account the data generated from longitudinal studies.
Optimizing inventories of diverse sites: insights from Barro Colorado Island birds
Authors: Watson David M.
Published: May 2010

1.Diverse sites have long‐attracted ecologists, yet the overwhelming variety of species can confound attempts to enumerate species richness. Various predictive methods estimate species richness by comparing the rate at which species are first detected with the rate at which they are detected again, yielding richness estimates of known precision without exhaustive sampling.

2.While frequently used for arthropods, predictive methods are rarely applied to vertebrate surveys where species identity is often a priority. Expressing observed richness as a function of estimated richness, an estimate of survey completeness can be derived, offering the potential for inventories of standardized precision for comparison and further analysis.

3.To realize this potential, I conducted 402 h of bird surveys on Barro Colorado Island (Panama) and performed a series of retrospective analyses to address three questions: (i) How much effort is required to achieve complete inventories (maximum completeness)? (ii) What is the least amount of effort required to yield robust richness estimates (maximum efficiency)? and (iii) How much effort is required to optimize sampling, balancing completeness and efficiency?

4.Whereas the richness estimate for all species required thirty 6‐h samples to attain maximum completeness, once migrants, waterbirds and non‐forest‐dependent species were excluded, the richness of forest‐dependent residents could be estimated to the same precision with fifteen samples and to 80% completeness with four samples.

5.Of the 186 bird species detected, 70 represented unique or duplicate records, seen in only one or two sampling periods. These low detectability species were dominated by migrants (28) and raptors (14) and also included seven waterbirds, five nocturnal species and four aerial foragers, justifying the widespread practice of excluding these groups from surveys of forest assemblages.

6.In addition to demonstrating the reliability of predictive approaches, this study demonstrates the practicality of results‐based stopping rules for sampling diverse sites, especially for targeted groups of species. Combining predictive methods with targeted sampling represents an efficient and rigorous design, increasing the number of sites that can be sampled and enhancing the overall power and value of the study.
A Perturbation Approach for Predicting Wave Propagation in One-Dimensional Nonlinear Periodic Structures
Authors: Narisetti Raj K. , Leamy Michael J. , Ruzzene Massimo
Published: May 2010

Wave propagation in one-dimensional nonlinear periodic structures is investigated through a novel perturbation analysis and accompanying numerical simulations. Several chain unit cells are considered featuring a sequence of masses connected by linear and cubic springs. Approximate closed-form, first-order dispersion relations capture the effect of nonlinearities on harmonic wave propagation. These relationships document amplitude-dependent behavior to include tunable dispersion curves and cutoff frequencies, which shift with wave amplitude. Numerical simulations verify the dispersion relations obtained from the perturbation analysis. The simulation of an infinite domain is accomplished by employing viscous-based perfectly matched layers appended to the chain ends. Numerically estimated wavenumbers show good agreement with the perturbation predictions. Several example chain unit cells demonstrate the manner in which nonlinearities in periodic systems may be exploited to achieve amplitude-dependent dispersion properties for the design of tunable acoustic devices.
Free In-Plane Vibration Analysis of Rectangular Plates With Elastically Point-Supported Edges
Authors: Du Jingtao , Liu Zhigang , Li Wen L. , Zhang Xuefeng , Li Wanyou
Published: May 2010

In comparison with the transverse vibrations of rectangular plates, far less attention has been paid to the in-plane vibrations even though they may play an equally important role in affecting the vibrations and power flows in a built-up structure. In this paper, a generalized Fourier method is presented for the in-plane vibration analysis of rectangular plates with any number of elastic point supports along the edges. Displacement constraints or rigid point supports can be considered as the special case when the stiffnesses of the supporting springs tend to infinity. In the current solution, each of the in-plane displacement components is expressed as a 2D Fourier series plus four auxiliary functions in the form of the product of a polynomial times a Fourier cosine series. These auxiliary functions are introduced to ensure and improve the convergence of the Fourier series solution by eliminating all the discontinuities potentially associated with the original displacements and their partial derivatives along the edges when they are periodically extended onto the entire x-y plane as mathematically implied by the Fourier series representation. This analytical solution is exact in the sense that it explicitly satisfies, to any specified accuracy, both the governing equations and the boundary conditions. Numerical examples are given about the in-plane modes of rectangular plates with different edge supports. It appears that these modal data are presented for the first time in literature, and may be used as a benchmark to evaluate other solution methodologies. Some subtleties are discussed about corner support arrangements.
Comparing the Performance of Optimally Tuned Dynamic Vibration Absorbers With Very Large or Very Small Moment of Inertia
Authors: Jang S.-J. , Brennan M. J. , Rustighi E.
Published: May 2010

In this article, the performance of a two degree-of-freedom dynamic vibration absorber (DVA) with very large or very small moment of inertia is studied. Although it has been shown previously that an optimally tuned DVA with a negligibly small moment of inertia marginally outperforms the optimally tuned DVA with a very large moment of inertia, the physical reasons for this have not been made clear. Using a simplified model of the stiffness elements of the DVA, it is shown that the two sets of parallel combinations of stiffness and damping elements of the DVA with negligibly small moments of inertia effectively act in series, rather than in parallel as in the other case. Furthermore, it is shown that the stiffness and damping elements can be represented as a single stiffness and a single damping element whose properties are frequency dependent. This frequency dependency means that there is additional freedom in choosing the optimum stiffness and damping of the DVA, which results in better performance.
Looseness Diagnosis of Rotating Machinery Via Vibration Analysis Through Hilbert–Huang Transform Approach
Authors: Wu T. Y. , Chung Y. L. , Liu C. H.
Published: May 2010

The objective of this research in this paper is to investigate the feasibility of utilizing the Hilbert–Huang transform method for diagnosing the looseness faults of rotating machinery. The complicated vibration signals of rotating machinery are decomposed into finite number of intrinsic mode functions (IMFs) by integrated ensemble empirical mode decomposition technique. Through the significance test, the information-contained IMFs are selected to form the neat time-frequency Hilbert spectra and the corresponding marginal Hilbert spectra. The looseness faults at different components of the rotating machinery can be diagnosed by measuring the similarities among the information-contained marginal Hilbert spectra. The fault indicator index is defined to measure the similarities among the information-contained marginal Hilbert spectra of vibration signals. By combining the statistical concept of Mahalanobis distance and cosine index, the fault indicator indices can render the similarities among the marginal Hilbert spectra to enhanced and distinguishable quantities. A test bed of rotor-bearing system is performed to illustrate the looseness faults at different mechanical components. The effectiveness of the proposed approach is evaluated by measuring the fault indicator indices among the marginal Hilbert spectra of different looseness types. The results show that the proposed diagnosis method is capable of classifying the distinction among the marginal Hilbert spectra distributions and thus identify the type of looseness fault at machinery.
Vibration Suppression in Structures Using Cable Actuators
Authors: Issa Jimmy , Mukherjee Ranjan , Shaw Steven W.
Published: May 2010

We investigate the use of cable tension for active vibration control in frame structures. A general formulation for this class of systems is developed using finite elements, which includes the dynamics of the structure and the effects of cable-structure interactions. It is found that the cable tension has two distinct effects on the structure. The first is a parametric effect in which the cable tension changes the stiffness of the structure, and the second is a direct effect that provides an external force on the structure. Based on this model, a general control scheme is developed that uses cable actuation to take advantage of these effects, both separately and together. The control scheme for all cases is based on modal amplitudes, and it applies and releases tension in such a manner that vibration energy is removed from the modes of the structure over a prescribed frequency range that depends on the bandwidth(s) of the actuator(s). The stability of the controlled systems is proven using nonlinear control theory. In addition, a method is developed for determining the optimal placement of cables for parametric stiffness control, which is verified via simulations. Finally, an experimental realization of the direct force control is tested on a frame structure and compared with simulations, demonstrating its effectiveness.
Band Gaps in a Multiresonator Acoustic Metamaterial
Authors: Huang G. L. , Sun C. T.
Published: May 2010

In this study, we investigated dispersion curves and the band gap structure of a multiresonator mass-in-mass lattice system. The unit cell of the lattice system consists of three separate masses connected by linear springs. It was demonstrated that the band gaps can be shifted by varying the spring constant and the magnitude of the internal masses. By using the conventional monatomic (single mass) lattice model as an equivalent system, the effective mass was found to become negative for frequencies in the band gaps. An attempt was made to represent the two-resonator mass-in-mass lattice with a microstructure continuum model. It was found that the microstructure continuum model can capture the dispersive behavior and band gap structure of the original two-resonator mass-in-mass system.
Wave Propagation in Auxetic Tetrachiral Honeycombs
Authors: Tee K. F. , Spadoni A. , Scarpa F. , Ruzzene M.
Published: May 2010

This paper describes a numerical and experimental investigation on the flexural wave propagation properties of a novel class of negative Poisson’s ratio honeycombs with tetrachiral topology. Tetrachiral honeycombs are structures defined by cylinders connected by four tangent ligaments, leading to a negative Poisson’s ratio (auxetic) behavior in the plane due to combined cylinder rotation and bending of the ribs. A Bloch wave approach is applied to the representative unit cell of the honeycomb to calculate the dispersion characteristics and phase constant surfaces varying the geometric parameters of the unit cell. The modal density of the tetrachiral lattice and of a sandwich panel having the tetrachiral as core is extracted from the integration of the phase constant surfaces, and compared with the experimental ones obtained from measurements using scanning laser vibrometers.
Visualization of anisotropic conductance in polydiacetylene crystal by dual-probe frequency-modulation atomic force microscopy/Kelvin-probe force microscopy
Authors: Tsunemi Eika , Kobayashi Kei , Matsushige Kazumi , Yamada Hirofumi
Published: May 2010

The authors recently developed a dual-probe atomic force microscope (DP-AFM) system as a powerful measurement or fabrication tool in the fields of nanoelectronics and nanobiology. In this study, they performed frequency-modulation Kelvin-probe force microscopy (FM-KFM) experiments on a polydiacetylene (PDA) single crystal using the DP-AFM system. While a bias voltage was locally applied to the PDA surface with one probe, the surface potential on the surrounding area was mapped with the other probe by FM-KFM. The surface potential images showed anisotropic distributions, which are explained by the anisotropic conductance of the PDA crystal due to the quasi-one-dimensional electronic band structure along the diacetylene main chain. They also discuss the mechanisms of charge injection from a probe to the PDA crystal and the difference in the anisotropic conductance ratio for electrons and holes.
Local dielectric spectroscopy of nanocomposite materials interfaces
Authors: Labardi Massimiliano , Prevosto Daniele , Nguyen Kim Hung , Capaccioli Simone , Lucchesi Mauro , Rolla Pierangelo
Published: May 2010

Local dielectric spectroscopy is performed to study how relaxation dynamics of a polyvinyl-acetate ultrathin film is influenced by inorganic nanoinclusions of a layered silicate (montmorillonite). Dielectric-loss spectra are measured by electrostatic-force microscopy in the frequency-modulation mode in ambient air. Spectral changes in both shape and relaxation time are evidenced across the boundary between pure polymer and montmorillonite sheets. Dielectric-loss imaging is also performed, evidencing spatial variations of dielectric properties near nanostructures with nanometer-scale resolution.
Investigation of interface between fullerene molecule and Si(111)-7×7 surface by noncontact scanning nonlinear dielectric microscopy
Authors: Kobayashi Shin-ichiro , Cho Yasuo
Published: May 2010

Fullerene (C60) molecules deposited on Si(111)-7×7 reconstructed (7×7) surface were investigated by noncontact scanning nonlinear dielectric microscopy (NC-SNDM) under ultrahigh vacuum conditions. Both topography and induced electric dipole moment of individual C60 molecules were successfully resolved with molecular-scale resolution. Charge transfer from the Si dangling bonds to the C60 molecule occurs and induces an electric dipole moment at almost all C60 sites. On the application of an alternating voltage, the downward electric dipole moment is nonlinearly modulated due to the electric property at the interface. The NC-SNDM technique can thus detect the electric dipole moment induced at interface between the C60 molecule and the Si adatom in 7×7 surface by the charge transfer from the Si adatom to C60 molecule.