bluuebunny/crossref_metadata_2025 huggingface dataset:
Wine tourists’ use of sources of information when visiting a USA wine region
Authors: Bruwer Johan , Thach Liz
Published: July 2013

This study investigates the sources of information people ( n = 334) use when deciding to embark on a wine tourism excursion by visiting a USA wine region environment. The study’s overall aim was to establish whether there are differences between first-time and repeat and between in-state- and out-of-state-based visitors in terms of sources of information they use to plan their visit to a wine region and how situational and sociodemographic variables relate to these. Specific differences exist in the information sources used by first-time and repeat wine tourists. Repeat visitors use informal sources such as exposure to a regional winery’s label, attending a tasting elsewhere and previous visits to the region significantly more than first-time visitors, who are more inclined to use formal sources such as brochures/pamphlets and the visitor information bureau. Word of mouth is used more than any other source by both in-state- and out-of-state-based visitors. Across the board, wine tourists did not differ much in their use of these sources by gender or age generation, with the exception of female millennials, in which case word of mouth and brochures/pamphlets were used significantly more.
Happiness and victimization: An empirical study for Switzerland
Authors: Staubli Silvia , Killias Martin , Frey Bruno S.
Published: July 2013

This paper explores if, and to what extent, crime affects happiness, using data from the Swiss Crime Survey 2011. Given the lack of research on the relationship between victimization and quality of life, it attempts to close an important gap in the existing literature. Results show negative effects on life satisfaction of theft, attempted burglary and consumer fraud, as well as of crimes against the person. Contrary to expectations, detrimental effects on quality of life do not decline consistently over time.
Treatment paradigms for ductus arteriosus aneurysms in adults
Authors: Psathas Emmanouil D , Katsargyris Athanasios , Lioudaki Stella , Moris Demetrios N , Doulaptsis Mikes , Klonaris Chris
Published: July 2013

We report two symptomatic cases of ductus arteriosus aneurysm (DDA) in adults treated in our department over a 5-years period. One patient underwent an open off-pump surgical procedure, while the second one was treated with partial aortic arch debranching and endovascular stent-grafting. DDA in adults is an uncommon condition and can present with rupture, hoarseness or symptoms of airway obstruction. Although indications for intervention are not clearly established, most authors advocate that DDAs should be treated regardless of their size, to avoid the risk of rupture, while others reserve intervention for symptomatic patients. We report on the management of these patients and provide an updated review of the current literature.
Modified osteotomy (Kanaya’s procedure) for congenital proximal radioulnar synostosis with posterior dislocation of radial head
Authors: Sakamoto S. , Doi K. , Hattori Y. , Dodakundi C. , Montales T.
Published: July 2013

Outcomes of Kanaya’s procedure for congenital proximal radioulnar synostosis varied depending on the type of radial head dislocation. In our series of 14 patients with 17 forearms who underwent Kanaya’s original procedure, the postoperative total rotation arc of the forearm was unsatisfactory in cases with posterior radial head dislocation. We examined the outcomes with respect to the type of radial head dislocation and radial shaft curvature. Radial shafts with a posterior radial head dislocation had only one curve and the radii of the curve were statistically smaller than those in anterior dislocated or enlocated heads, which had two curves. As a result, we modified the osteotomy site for proximal radioulnar synostosis with posterior radial head dislocation and achieved improved forearm rotation and physiological rotation of the radial head in our latest two cases.
Fine-tuning of microRNA-mediated repression of mRNA by splicing-regulated and highly repressive microRNA recognition element
Authors: Wu Cheng-Tao , Chiou Chien-Ying , Chiu Ho-Chen , Yang Ueng-Cheng
Published: July 2013

Background

MicroRNAs are very small non-coding RNAs that interact with microRNA recognition elements (MREs) on their target messenger RNAs. Varying the concentration of a given microRNA may influence the expression of many target proteins. Yet, the expression of a specific target protein can be fine-tuned by alternative cleavage and polyadenylation to the corresponding mRNA.

Results

This study showed that alternative splicing of mRNA is a fine-tuning mechanism in the cellular regulatory network. The splicing-regulated MREs are often highly repressive MREs. This phenomenon was observed not only in the hsa-miR-148a-regulated DNMT3B gene, but also in many target genes regulated by hsa-miR-124, hsa-miR-1, and hsa-miR-181a. When a gene contains multiple MREs in transcripts, such as the VEGF gene, the splicing-regulated MREs are again the highly repressive MREs. Approximately one-third of the analysable human MREs in MiRTarBase and TarBase can potentially perform the splicing-regulated fine-tuning. Interestingly, the high (+30%) repression ratios observed in most of these splicing-regulated MREs indicate associations with functions. For example, the MRE-free transcripts of many oncogenes, such as N-RAS and others may escape microRNA-mediated suppression in cancer tissues.

Conclusions

This fine-tuning mechanism revealed associations with highly repressive MRE. Since high-repression MREs are involved in many important biological phenomena, the described association implies that splicing-regulated MREs are functional. A possible application of this observed association is in distinguishing functionally relevant MREs from predicted MREs.
A case of adaptation through a mutation in a tandem duplication during experimental evolution in Escherichia coli
Authors: Maharjan Ram P , Gaffé Joël , Plucain Jessica , Schliep Martin , Wang Lei , Feng Lu , Tenaillon Olivier , Ferenci Thomas , Schneider Dominique
Published: July 2013

Background

DNA duplications constitute important precursors for genome variation. Here we analyzed an unequal duplication harboring a beneficial mutation that may provide alternative evolutionary outcomes.

Results

We characterized this evolutionary event during experimental evolution for only 100 generations of an Escherichia coli strain under glucose limitation within chemostats. By combining Insertion Sequence based Restriction Length Polymorphism experiments, pulsed field gel electrophoresis and two independent genome re-sequencing experiments, we identified an evolved lineage carrying a 180 kb duplication of the 46’ region of the E. coli chromosome. This evolved duplication revealed a heterozygous state, with one copy harboring a 2668 bp deletion that included part of the ogrK gene and both the yegR and yegS genes. By genetically manipulating ancestral and evolved strains, we showed that the single yegS inactivation was sufficient to confer a frequency dependent fitness increase under the chemostat selective conditions in both the ancestor and evolved genetic contexts, implying that the duplication itself was not a direct fitness contributor. Nonetheless, the heterozygous duplicated state was relatively stable in the conditions prevailing during evolution in chemostats, in striking contrast to non selective conditions in which the duplication resolved at high frequency into either its ancestral or deleted copy.

Conclusions

Our results suggest that the duplication state may constitute a second order selection process providing higher evolutionary potential. Moreover, its heterozygous nature may provide differential evolutionary opportunities in alternating environments. Our results also highlighted how careful analyses of whole genome data are needed to identify such complex rearrangements.
No sex-specific difference in disease trajectory in multiple sclerosis patients before and after age 50
Authors: Bove Riley , Musallam Alexander , Healy Brian C , Houtchens Maria , Glanz Bonnie I , Khoury Samia , Guttmann Charles R , De Jager Philip L , Chitnis Tanuja
Published: July 2013

Background

The disease course in multiple sclerosis (MS) is influenced by many factors, including age, sex, and sex hormones. Little is known about sex-specific changes in disease course around age 50, which may represent a key biological transition period for reproductive aging.

Methods

Male and female subjects with no prior chemotherapy exposure were selected from a prospective MS cohort to form groups representing the years before (38–46 years, N=351) and after (54–62 years, N=200)age 50. Primary analysis assessed for interaction between effects of sex and age on clinical (Expanded Disability Status Scale, EDSS; relapse rate) and radiologic (T2 lesion volume, T2LV; brain parenchymal fraction, BPF) outcomes. Secondarily, we explored patient-reported outcomes (PROs).

Results

As expected, there were age- and sex- related changes with male and older cohorts showing worse disease severity (EDSS), brain atrophy (BPF), and more progressive course.

There was no interaction between age and sex on cross-sectional adjusted clinical (EDSS, relapse rate) or radiologic (BPF, T2LV) measures, or on 2-year trajectories of decline.

There was a significant interaction between age and sex for a physical functioning PRO (SF-36): the older female cohort reported lower physical functioning than men (p=0.002). There were no differences in depression (Center for Epidemiological Study – Depression, CES-D) or fatigue (Modified Fatigue Impact Scale, MFIS) scores.

Conclusions

There was no interaction between age and sex suggestive of an effect of reproductive aging on clinical or radiologic progression. Prospective analyses across the menopausal transition are needed.
The role of natural health products (NHPs) in dietetic practice: results from a survey of Canadian dietitians
Authors: Hirschkorn Kristine , Walji Rishma , Boon Heather
Published: July 2013

Background

Registered dietitians (RDs) play a key role in disseminating information about nutrition and intervening in nutrition-related disorders in the Canadian context. Natural health products (NHPs) are increasingly associated with nutrition in patient and health professional discussions. For this study, NHPs were divided into three categories: nutritional supplements (NS); functional foods/nutraceuticals (FF/N); and herbal preparations (HP). The objective was to explore RDs’ perceptions about their professional roles and responsibilities with respect to three categories of natural health products (NHPs).

Methods

This research consisted of an on-line survey of registered dietitians (RDs) in Ontario.

Surveys were distributed electronically to all practicing RDs in Ontario by the College of Dietitians of Ontario. There were 558 survey respondents, a response rate of 20%.

Results

The vast majority of RDs reported being consulted by clients about all product categories (98% for NS; 94% for FF/N; 91% for HP), with RDs receiving the most frequent questions about NS and the least frequent about HP. 74% of RDs believed that NS are included within the current scope of practice, compared to 59% for FF/N and 14% for HP. Even higher numbers believed that these products should be included: 97% for NS, 91% for FF/N and 47% for HP. RDs who report personally ingesting FF/N and HP were significantly more likely to report that these products should be in the dietetic scope of practice. In contrast, RDs who provide one-on-one counselling services or group-level counselling/workshops were significantly less likely to believe HP should be in the dietetic scope of practice.

Conclusions

Opinions of RDs indicated that NS and FF/N (and possibly HP) fall within, or should fall within, RDs’ scope of practice. Opportunity exists for RDs to undertake a professional role with respect to NHPs. Policy clarification regarding RD roles is needed.
Tunable insulator-quantum Hall transition in a weakly interacting two-dimensional electron system
Authors: Lo Shun-Tsung , Wang Yi-Ting , Lin Sheng-Di , Strasser Gottfried , Bird Jonathan P , Chen Yang-Fang , Liang Chi-Te
Published: July 2013

We have performed low-temperature measurements on a gated two-dimensional electron system in which electron–electron (e-e) interactions are insignificant. At low magnetic fields, disorder-driven movement of the crossing of longitudinal and Hall resistivities (ρ
xx and ρ
xy) can be observed. Interestingly, by applying different gate voltages, we demonstrate that such a crossing at ρ
xx ~ ρ
xy can occur at a magnetic field higher, lower, or equal to the temperature-independent point in ρ
xx which corresponds to the direct insulator-quantum Hall transition. We explicitly show that ρ
xx ~ ρ
xy occurs at the inverse of the classical Drude mobility 1/μ
D rather than the crossing field corresponding to the insulator-quantum Hall transition. Moreover, we show that the background magnetoresistance can affect the transport properties of our device significantly. Thus, we suggest that great care must be taken when calculating the renormalized mobility caused by e-e interactions.
In situ preparation of monodispersed Ag/polyaniline/Fe3O4 nanoparticles via heterogeneous nucleation
Authors: Bian Longchun , Bao Lixia , Wang Jiliang , Lei Jingxin
Published: July 2013

Acrylic acid and styrene were polymerized onto monodispersed Fe3O4 nanoparticles using a grafting copolymerization method. Aniline molecules were then bonded onto the Fe3O4 nanoparticles by electrostatic self-assembly and further polymerized to obtain uniform polyaniline/Fe3O4 (PANI/Fe3O4) nanoparticles (approximately 35 nm). Finally, monodispersed Ag/PANI/Fe3O4 nanoparticles were prepared by an in situ reduction reaction between emeraldine PANI and silver nitrate. Fourier transform infrared and UV-visible spectrometers and a transmission electron microscope were used to characterize both the chemical structure and the morphology of the resulting nanoparticles.
Some fixed point results for multi-valued mappings in partial metric spaces
Authors: Ahmad Jamshaid , Di Bari Cristina , Cho Yeol Je , Arshad Muhammad
Published: July 2013

In this paper, we obtain some fixed point results for multi-valued mappings in partial metric spaces. Our results unify, generalize and complement various known comparable results from the current literature. An example is also included to illustrate the main result in the paper.

MSC:46S40, 47H10, 54H25.
Evaluation of a multisite educational intervention to improve mobilization of older patients in hospital: protocol for mobilization of vulnerable elders in Ontario (MOVE ON)
Authors: Liu Barbara , Almaawiy Ummukulthum , Moore Julia E , Chan Wai-Hin , Straus Sharon E ,   the MOVE ON Team
Published: July 2013

Background

Functional decline is a common adverse outcome of hospitalization in older people. Often, this decline is not related to the illness that precipitated admission, but to the process of care delivered in hospital. The association between immobility and adverse consequences is well established, yet older inpatients spend significant amounts of time supine in bed. We aim to implement and evaluate the impact of an evidence-based strategy to promote early mobilization and prevent functional decline in older patients admitted to university-affiliated acute care hospitals in Ontario, Canada. We will implement a multi-component educational intervention to support a change in practice to enhance mobilization of older patients.

Methods/design

Implementation of our early mobilization strategy is guided by the Knowledge to Action Cycle. Through focus groups with frontline staff, we will identify barriers and facilitators to early mobilization. We will tailor the intervention at each site to the identified barriers and facilitators, focusing on the following key messages: to complete a mobility assessment and care plan within 24 hours of the decision to admit patients aged 65 years and older; to achieve mobilization at least 3 times per day; and, to ensure that mobilization is scaled and progressive. The primary outcome, number of patients observed out of bed, will be documented three times per day (in the morning, at lunch and in the afternoon), two days each week. This data collection will occur over 3 phases: pre-implementation (10 weeks), implementation (8 weeks), and post-implementation (20 weeks).

Discussion

This is the first large, multisite study to evaluate the impact of a multi-component knowledge translation strategy on rates of mobilization of older patients in hospital. Our implementation is framed by the Knowledge to Action Cycle, and the intervention is being adapted to the local context. These unique features render our intervention approach more generalizable to multiple practice settings. Contextualization of the intervention has also facilitated engagement of participants from multiple hospitals. Upon completion of this study, we will better understand the barriers and facilitators to implementing an early mobilization strategy across a spectrum of hospitals, as well as the impact of a mobilization strategy.
Reirradiation in progressive high-grade gliomas: outcome, role of concurrent chemotherapy, prognostic factors and validation of a new prognostic score with an independent patient cohort
Authors: Scholtyssek Felix , Zwiener Isabella , Schlamann Annika , Seidel Clemens , Meixensberger Jürgen , Bauer Manfred , Hoffmann Karl-Titus , Combs Stephanie E , von Bueren André O , Kortmann Rolf-Dieter , Müller Klaus
Published: July 2013

Purposes

First, to evaluate outcome, the benefit of concurrent chemotherapy and prognostic factors in a cohort of sixty-four high-grade glioma patients who underwent a second course of radiation therapy at progression. Second, to validate a new prognostic score for overall survival after reirradiation of progressive gliomas with an independent patient cohort.

Patients and methods

All patients underwent fractionated reirradiation with a median physical dose of 36 Gy. Median planned target volume was 110.4 ml. Thirty-six patients received concurrent chemotherapy consisting in 24/36 cases (67%) of carboplatin and etoposide and in 12/36 cases (33%) of temozolomide. We used the Kaplan Meier method, log rank test and proportional hazards regression analysis for statistical assessment.

Results

Median overall survival from the start of reirradiation was 7.7 ± 0.7 months. Overall survival rates at 6 and 12 months were 60 ± 6% and 24 ± 6%, respectively. Despite relatively large target volumes we did not observe any major acute toxicity. Concurrent chemotherapy did not appear to improve outcome. In contrast, female gender, young age, WHO grade III histology, favorable Karnofsky performance score and complete resection of the tumor prior to reirradiation were identified as positive prognostic factors for overall survival. We finally validated a recent suggestion for a prognostic score with our independent but small patient cohort. Our preliminary findings suggest that its ability to discriminate between different prognostic groups is limited.

Conclusions

Outcome of our patients was comparable to previous studies. Even in case of large target volumes reirradiation seems to be feasible without observing major toxicity. The benefit of concurrent chemotherapy is still elusive. A reassessment of the prognostic score, tested in this study, using a larger patient cohort is needed.
Addition of a carbohydrate-binding module enhances cellulase penetration into cellulose substrates
Authors: Reyes-Ortiz Vimalier , Heins Richard A , Cheng Gang , Kim Edward Y , Vernon Briana C , Elandt Ryan B , Adams Paul D , Sale Kenneth L , Hadi Masood Z , Simmons Blake A , Kent Michael S , Tullman-Ercek Danielle
Published: July 2013

Introduction

Cellulases are of great interest for application in biomass degradation, yet the molecular details of the mode of action of glycoside hydrolases during degradation of insoluble cellulose remain elusive. To further improve these enzymes for application at industrial conditions, it is critical to gain a better understanding of not only the details of the degradation process, but also the function of accessory modules.

Method

We fused a carbohydrate-binding module (CBM) from family 2a to two thermophilic endoglucanases. We then applied neutron reflectometry to determine the mechanism of the resulting enhancements.

Results

Catalytic activity of the chimeric enzymes was enhanced up to three fold on insoluble cellulose substrates as compared to wild type. Importantly, we demonstrate that the wild type enzymes affect primarily the surface properties of an amorphous cellulose film, while the chimeras containing a CBM alter the bulk properties of the amorphous film.

Conclusion

Our findings suggest that the CBM improves the efficiency of these cellulases by enabling digestion within the bulk of the film.
Distinct mechanism of formation of the 48, XXYY karyotype
Authors: Balsera Aránzazu Margallo , Estévez Manuela Núñez , Beltrán Emilia Balboa , Sánchez-Giralt Plácida , García Luz González , Moreno Trinidad Herrera , García de Cáceres Mayte , Carbonell Pérez José M , Gómez Enrique Galán , Rodríguez-López Raquel
Published: July 2013

Background

To expose the unusual nature of a coincident sex chromosomal aneuploidy in a patient and his father. Molecular mechanisms involved probably are based on the sperm chromosome of paternal origin, which determine the mode of formation. Conventional cytogenetics techniques and multiple Quantitative Fluorescent PCR of STR markers in sexual chromosomes in the patient and his parents.

Results

48,XXYY and 47,XYY aneuploidies in the patient and his father, respectively, were identified. The additional X and Y chromosomes showed parental origin.

Conclusions

An infrequent origin of the 48,XXYY syndrome was demonstrated. Mostly, it is thought to result from an aneuploid sperm produced through two consecutive non disjunction events in both meiosis I and II in a chromosomally normal father, but in our father’s patient a 47,XYY was discovered. It is suggested that a higher incidence of 24,XY and 24,YY sperm may be possible in 47,XYY individuals andan increased risk for aneuploidy pregnancies may exist. Although 48,XXYY patients and Klinefelter syndrome are often compared, recently they are regarded as a distinct genetic and clinical entity.
Earnings growth of Mexican immigrants: new versus traditional destinations
Authors: Kaushal Neeraj , Shang Ce
Published: July 2013

We study the earnings of Mexican immigrants in their traditional and newer destinations in the US. Analysis based on longitudinal data suggests that during 2001-2009, the real wage of Mexican immigrants increased 1-2% a year at the traditional destinations, but remained mostly statistically insignificant at the newer destinations. Mexicans at the traditional destinations exhibited greater residential stability: internal migration, non-follow up in the longitudinal data, and predicted return migration were higher among immigrants at the newer destinations than among immigrants at the traditional destinations. Predicted return migration was found to be selective on past earnings among men, but not among women. For men, a 10 percentage point increase in predicted probability of return migration was associated with a 0.3-0.5% lower wage in the year prior to return.
Thermal, mechanical, and moisture absorption properties of egg white protein bioplastics with natural rubber and glycerol
Authors: Jones Alexander , Zeller Mark Ashton , Sharma Suraj
Published: July 2013

Petroleum-based plastics have many drawbacks: the large amount of energy required to produce the plastic, the waste generated as a result of plastic production, and the accumulation of waste due to slow degradation rate. It is because of these negative attributes of conventional plastic use that attention is being focused on environmentally friendly plastics from alternative sources. Albumin protein provides one possible source of raw material, with inherent antimicrobial properties that may make it suitable for medical applications. We conducted this study to investigate the various bioplastic properties of the albumin with the use of three plasticizers - water, glycerol, and natural rubber latex. Based on results, 75:25 albumin-water, 75:25 albumin-glycerol, and 80:20 albumin-natural rubber were the best blending ratios for each plasticizer for a subsequent time study to determine water stability, with the 80:20 albumin-natural rubber blend ratio having possessed the best thermal, tensile, and viscoelastic properties overall.
Analysis of polymorphisms in the circadian-related genes and breast cancer risk in Norwegian nurses working night shifts
Authors: Zienolddiny Shanbeh , Haugen Aage , Lie Jenny-Anne Sigstad , Kjuus Helge , Anmarkrud Kristine Haugen , Kjærheim Kristina
Published: July 2013

Introduction

Some studies have suggested that night work may be associated with an increased risk of breast cancer in nurses. We aimed to explore the role of circadian gene polymorphisms in the susceptibility to night work-related breast cancer risk.

Methods

We conducted a nested case-control study of Norwegian nurses comprising 563 breast cancer cases and 619 controls within a cohort of 49,402 Norwegian nurses ages 35 to 74 years. We studied 60 single-nucleotide polymorphisms (SNPs) in 17 genes involved in the regulation of the circadian rhythm in cases and controls. The data were analyzed in relation to the two exposure variables "maximum number of consecutive night shifts ever worked" and "maximum number of consecutive night shifts worked for at least 5 years." The odds of breast cancer associated with each SNP was calculated in the main effects analysis and in relation to night shift work. The statistically significant odds ratios were tested for noteworthiness using two Bayesian tests: false positive report probability (FPRP) and Bayesian false discovery probability (BFDP).

Results

In the main effects analysis, CC carriers of rs4238989 and GG carriers of rs3760138 in the AANAT gene had increased risk of breast cancer, whereas TT carriers of BMAL1 rs2278749 and TT carriers of CLOCK rs3749474 had reduced risk. The associations were found to be noteworthy using both the FPRP and BFDP tests. With regard to the effect of polymorphisms and night work, several significant associations were observed. After applying FPRP and BFDP in women with at least four night shifts, an increased risk of breast cancer was associated with variant alleles of SNPs in the genes AANAT (rs3760138, rs4238989), BMAL1 (rs2290035, rs2278749, rs969485) and ROR-b (rs3750420). In women with three consecutive night shifts, a reduced risk of breast cancer was associated with carriage of variant alleles of SNPs in CLOCK (rs3749474), BMAL1 (rs2278749), BMAL2 (rs2306074), CSNK1E (rs5757037), NPAS2 (rs17024926), ROR-b (rs3903529, rs3750420), MTNR1A (rs131113549) and PER3 (rs1012477).

Conclusions

Significant and noteworthy associations between several polymorphisms in circadian genes, night work and breast cancer risk were found among nurses who had worked at least three consecutive night shifts.
Minireview: Nutrient Sensing by G Protein-Coupled Receptors
Authors: Wauson Eric M. , Lorente-Rodríguez Andrés , Cobb Melanie H.
Published: July 2013

G protein-coupled receptors (GPCRs) are membrane proteins that recognize molecules in the extracellular milieu and transmit signals inside cells to regulate their behaviors. Ligands for many GPCRs are hormones or neurotransmitters that direct coordinated, stereotyped adaptive responses. Ligands for other GPCRs provide information to cells about the extracellular environment. Such information facilitates context-specific decision making that may be cell autonomous. Among ligands that are important for cellular decisions are amino acids, required for continued protein synthesis, as metabolic starting materials and energy sources. Amino acids are detected by a number of class C GPCRs. One cluster of amino acid-sensing class C GPCRs includes umami and sweet taste receptors, GPRC6A, and the calcium-sensing receptor. We have recently found that the umami taste receptor heterodimer T1R1/T1R3 is a sensor of amino acid availability that regulates the activity of the mammalian target of rapamycin. This review focuses on an array of findings on sensing amino acids and sweet molecules outside of neurons by this cluster of class C GPCRs and some of the physiologic processes regulated by them.
Private Information and the Allocation of Land Use Subsidies in Malawi
Authors: Jack B. Kelsey
Published: July 2013

Efficient targeting of public programs is difficult when the cost or benefit to potential recipients is private information. This study illustrates the potential of self-selection to improve allocational outcomes in the context of a program that subsidizes tree planting in Malawi. Landholders who received a tree planting contract as a result of bidding in an auction kept significantly more trees alive over a three year period than did landholders who received the contract through a lottery. The gains from targeting on private information through the auction represent a 30 percent cost savings per surviving tree for the implementing organization. (JEL D04, D44, D82, O13, Q24, Q28)
Experimental Evidence on the Effects of Home Computers on Academic Achievement among Schoolchildren
Authors: Fairlie Robert W , Robinson Jonathan
Published: July 2013

Computers are an important part of modern education, yet many schoolchildren lack access to a computer at home. We test whether this impedes educational achievement by conducting the largest-ever field experiment that randomly provides free home computers to students. Although computer ownership and use increased substantially, we find no effects on any educational outcomes, including grades, test scores, credits earned, attendance, and disciplinary actions. Our estimates are precise enough to rule out even modestly-sized positive or negative impacts. The estimated null effect is consistent with survey evidence showing no change in homework time or other “intermediate” inputs in education. (JEL I21, I24, J13)
Bringing Education to Afghan Girls: A Randomized Controlled Trial of Village-Based Schools
Authors: Burde Dana , Linden Leigh L
Published: July 2013

We conduct a randomized evaluation of the effect of village-based schools on children's academic performance using a sample of 31 villages and 1,490 children in rural northwestern Afghanistan. The program significantly increases enrollment and test scores among all children, but particularly for girls. Girls' enrollment increases by 52 percentage points and their average test scores increase by 0.65 standard deviations. The effect is large enough that it eliminates the gender gap in enrollment and dramatically reduces differences in test scores. Boys' enrollment increases by 35 percentage points, and average test scores increase by 0.40 standard deviations. (JEL I21, J16, O15, O18)
The Effects of “Girl-Friendly” Schools: Evidence from the BRIGHT School Construction Program in Burkina Faso
Authors: Kazianga Harounan , Levy Dan , Linden Leigh L , Sloan Matt
Published: July 2013

We evaluate a “girl-friendly” primary school program in Burkina Faso using a regression discontinuity design. After 2.5 years, the program increased enrollment by 19 percentage points and increased test scores by 0.41 standard deviations. For those caused to attend school, scores increased by 2.2 standard deviations. Girls' enrollment increased by 5 percentage points more than boys' enrollment, but they experienced the same increase in test scores as boys. The unique characteristics of the schools are responsible for increasing enrollment by 13 percentage points and test scores by 0.35 standard deviations. They account for the entire difference in the treatment effects by gender. (JEL I21, I28, J16, O15)
Characteristics and Accumulation Mechanism of Quasi-Layered Ordovician Carbonate Reservoirs in the Tazhong Area, Tarim Basin
Authors: Wang Zhaoming , Su Jin , Zhu Guangyou , Han Jianfa , Wang Yu
Published: July 2013

Weathered crust reservoirs of marine carbonate rocks and large-area quasi-layered carbonate reservoirs controlled by massive unconformity surfaces have become an important play for exploration of marine hydrocarbons across China. In the Tazhong area, oil and gas originating from the marine facies of the Ordovician Yingshan formation, present large-scale integrated continuous accumulation along massive structures. In particular, they are accumulated continuously in layered form in carbonate fracture-cavity reservoir system, and not controlled by tertiary structural belts. Moreover, the Yingshan reservoirs are complex in types, comprising cross distribution of high gas/oil ratio (GOR) condensate gas reservoirs, volatile oil reservoirs and normal oil reservoirs, and large burial depth span and high heterogeneity of quasi-layered reservoirs. The complexity in diagenesis and accumulation lead to the unique distribution and enrichment of carbonate reservoirs in the Tazhong area. The analysis of blow-down and leakage depths, heterogeneity, and physical properties of pores, caves and fractures of the Yingshan formation carbonate reservoirs indicates that the interstratal karsts have superimposed with faults and fractures to form fracture zones, so that the reservoir bodies present integrated continuous distribution characteristics spatially, providing favorable conditions for quasi-layered continuous enrichment of oil and gas. During late periods, a massive amount of natural gas had been filled along the gas-source faults. Based on the variations of relative contents of light hydrocarbons and aromatic naphthalene homologs in crude oil, it is found that the quasi-layered continuous carbonate reservoirs in the Tazhong area are different in terms of the properties of oil and gas and the types of oil reservoirs as a result of the formation of high GOR high-yield condensate gas reservoirs near the oil/gas-source faults due to gas washing, migration and fractionation. Late gas charge and transformation process acting on earlier oil reservoirs is an important geochemical action in the formation mechanism of carbonate reservoirs in the Tazhong area.
Noise Abatement in a Reverberant Sound Field Using the Particle Swarm Method
Authors: Chiu Min-Chie
Published: July 2013

Noise control is essential in an enclosed machine room where the noise level is regulated by the occupational safety and health act. In order to overcome noise hybridized by a direct and reverberant sound wave, a sound absorber in conjunction with an acoustical enclosure has been used. However, the traditional method for designing a sound absorber and an acoustical enclosure has proven to be time-consuming. In order to efficiently control the noise level specified by the Environmental Protection Agency, interest in shape optimization of a sound absorber as well as acoustical enclosure is coming to the forefront.

In this paper, the numerical technique of particle swarm optimization ( PSO) in conjunction with the theoretical sound propagation model and the method of minimized variation square are applied in the following numerical optimizations. Before noise abatement is carried out, the accuracy of the mathematical model in a single-noise enclosed system will be checked by SoundPlan (a professional simulation package). Moreover, the noise abatement of five kinds of multi-equipment machine rooms using the PSO method has been exemplified and fully explored. The results reveal that both the acoustical panel and the acoustical enclosure can be precisely designed. Consequently, this paper may provide an efficient and rapid way of depressing both the direct and reflected sound wave by using a well-designed acoustical panel and acoustical enclosure in a complicated sound field.
Elastic Layers to Reduce Sound Transmission in Lightweight Buildings
Authors: Ljunggren Fredrik , Ågren Anders
Published: July 2013

To obtain satisfactory sound insulation is a challenging task when designing lightweight buildings. Poor performance at low frequencies as well as severe flanking transmission has traditionally often been more pronounced compared to heavier constructions. In the present casestudy based paper, various aspects of using elastic layers to improve sound insulation in lightweight buildings are considered.

The effect on impact and airborne sound insulation by using two different kinds of vibration insulators between floor plans was examined together with the effect of using glues of various degree of elasticity in the construction. In situ measurements were performed inside a four-storey wooden frame based residential building and statistically significant variations in sound insulation were found.

The efficiency of the two vibration insulators was further evaluated by vibration reduction measurements over the junctions. The difference in vibration reduction was found to be nearly constant in the frequency range 50–1000 Hz while the improvement of impact sound insulation increased by frequency.

A long term test of elastic glues was also conducted, during three years, for stability over time. The best glues preserved a significantly higher damping ratio over time compared to the main part of the glues.
The Interrelationship between Room Acoustics Parameters as Measured in University Classrooms Using Four Source Configurations
Authors: Nestoras Christos , Dance Stephen
Published: July 2013

This paper investigates the interrelation of room acoustics parameters as measured in lecture theatres/classrooms using four sound source configurations. Ten typical rooms were selected as representative of university premises and measured to ISO 3382 standards. The study focuses initially on the type of sound source used, to establish the suitability of multi source based measurements in assessing the acoustics of classrooms. Acoustic performance is then discussed in the context of the relationship between room acoustics parameters with and without significant background noise, with a particular focus on speech intelligibility. To facilitate a more efficient discernment of results, EDT, T30, Clarity indices and MTI were considered, as they are commonly included in general room acoustics assessments. Either of the source configurations was found to be suitable for performing general purpose measurements in (small) rooms. Clarity and EDT were found to be linearly related to the modulation transfer index in noiseless conditions, in line with earlier findings, thus an excellent predictor of STI. Background noise could be ascertained as of primary importance in the case of a non linear relation.
Comparative Study on the Effect of Number of Girders on Live Load Distribution in Integral Abutment and Simply Supported Bridge Girders
Authors: Yalcin O. Fatih , Dicleli Murat
Published: July 2013

In this study, the effect of the number of prestressed concrete girders on the distribution of live load effects among the girders of integral abutment bridges (IABs) and simply supported bridges (SSBs) is investigated. For this purpose, two and three dimensional finite element models (FEMs) of several single-span IABs and SSBs are built and analyzed. In the analyses, bridges with various superstructure properties, such as span length, girder type and size, slab thickness are considered. The finite element analyses (FEA) results are then used to calculate the live load distribution factors (LLDFs) for the girders of IABs and SSBs as a function of the number of girders. Comparison of the analyses results revealed that, LLDFs for SSBs vary slightly as the number of girders changes. However, in the case of IABs, it is found that while the LLDFs for the girder moments decrease significantly as the number of girders increases, the number of girders has a negligible effect on the LLDFs for the girder shear. Accordingly, the number of girders is added as a new parameter to the previously developed correction factors for AASHTO LRFD LLDFs for the girder moment. It is observed that the developed formulae yield a reasonably good estimate of live load effects in prestressed concrete IAB girders.
Buckling Strength of Single Angle Struts Part 2: Angles Connected by One Leg at Both Ends
Authors: Chen Shaofan , Wang Xiantie
Published: July 2013

A single angle strut connected at both ends by one leg is simple in execution, but complex in behavior. As a monosymmetric section, the angle is subjected simultaneously to compression, biaxial bending and torsion. Furthermore, there exist at the two ends rotational restraints whose rigidity depends on the member arrangement and joint detailing of the truss. So, a rigorous solution of the bearing capacity of such angle is very difficult to establish. The common practice in design work is to transform this complex problem into the buckling of an axially compressed strut, hinged at both ends, by taking an equivalent slenderness ratio.

In this study, new formulas for this equivalent slenderness are suggested, where a concept of partial adjustment is introduced so that they apply to angles of high strength steel as well as to those of low carbon steel.

The detrimental effect of torsion on the strut capacity is not negligible when the angle has slender leg, especially for high strength steel. Formulas of reduction factor to the member yield strength are proposed in this regard and are given as a function of the flat width-thickness ratio instead of the overall width-thickness ratio of the leg. These formulas, in conjunction with those for equivalent slenderness, correlate well with the test program of angle struts, steel grade 460 MPa.

Lastly, limitations to the formulas of equivalent slenderness are discussed.
Combined Effect of Suspended Particles and Rotation on Double-Diffusive Convection in a Viscoelastic Fluid Saturated by a Darcy-Brinkman Porous Medium
Authors: Rana G. C. , Thakur R. C.
Published: July 2013

In this paper, the combined effect of suspended (fine dust) particles and rotation on the onset of double-diffusive convection in a viscoelastic fluid in porous medium is studied. For the porous medium, the Brinkman model is employed and Walters' (model B′) model is used to characterize viscoelastic fluid. By applying normal mode analysis method, the dispersion relation has been derived and solved analytically. It is observed that the rotation, stable solute gradient, suspended particles, gravity field and viscoelasticity introduce oscillatory modes. For stationary convection, it is observed that the rotation, stable solute gradient have stabilizing effect and suspended particles have destabilizing effect on the system whereas Darcy number and medium permeability have stabilizing/destabilizing effects under certain conditions. The effects of rotation, stable solute gradient, suspended particles, Darcy number and medium permeability have also been investigated.
Development of an Automated Regional Coupled Atmosphere-Ocean Modeling System for Coastal Kalpakkam
Authors: Bonthu SubbaReddy , Sasmal Kaushik , Warrior Hari V , Maity Subhendu
Published: July 2013

In this paper the development of an automated flux coupling mechanism applied to a Regional Coupled Atmosphere-Ocean Model (RCAOM) is reported. The coupler serves as an interface between two state-of-the-art models viz. Advanced Weather Research and Forecasting Model (WRF) and Princeton Ocean Model (POM). It has direct significance for ocean state forecasting studies such as prediction of sea-surface temperature (SST), surface circulations etc. RCAOM simulates local processes like upwelling along coastal Kalpakkam situated on the east coast of India and is also used to observe thermal recirculation at intake locations of cooling Jetties for the two nuclear power plants, Madras Atomic Power Plant (MAPS) and Prototype Fast Breeder Reactor (PFBR). The simulations reveal that the rise of temperature at intake locations of MAPS and PFBR occurs due to reversal wind system and exchange of heat fluxes and secondly upwelling is observed at the outfall location due to topographically induced effect in the absence of thermal discharge.
Learning, Words and Actions: Experimental Evidence on Coordination-Improving Information
Authors: Jacquemet Nicolas , Zylbersztejn Adam
Published: July 2013

We experimentally study an asymmetric coordination game with two Nash equilibria: one is Pareto-efficient, the other is Pareto-inefficient and involves a weakly dominated strategy. We assess whether information about the interaction partner helps eliminate the imperfect equilibrium. Our treatments involve three information-enhancing mechanisms: repetition and two kinds of individual signals: messages from partner or observation of his past choices. Repetition-based learning increases the frequencies of the most efficient outcome and the most costly strategic mismatch. Moreover, it is superseded by individual signals. Like previous empirical studies, we find that signals provide a screening of partners’ intentions that reduces the frequency of coordination failures. Unlike these studies, we find that the transmission of information between partners, either via messages or observation, does not suffice to significantly increase the overall efficiency of outcomes. This happens mostly because information does not restrain the choice of the dominated action by senders.
Oxidative in vitro folding of a cysteine deficient variant of the G protein-coupled neuropeptide Y receptor type 2 improves stability at high concentration
Authors: Witte Kristina , Kaiser Anette , Schmidt Peter , Splith Victoria , Thomas Lars , Berndt Sandra , Huster Daniel , Beck-Sickinger Annette G.
Published: July 2013

In vitro folding of G protein-coupled receptors into a detergent environment represents a promising strategy for obtaining sufficient amounts of functional receptor molecules for structural studies. Typically, these preparations exhibit a poor long-term stability especially at the required high protein concentration. Here, we report a protocol for the stabilization of the Escherichia coli-expressed and subsequently folded neuropeptide Y receptor type 2. We identified the free cysteines in the receptor as one major reason for intermolecular protein aggregation. Therefore, six out of the eight cysteine residues were mutated to alanine or serine without any significant loss of functionality of the receptor as demonstrated in cell culture models. Furthermore, the disulfide bond between the remaining two cysteines was irreversibly formed by applying oxidative in vitro folding. Applying this strategy, the stability of the functionally folded Y2 receptor could be increased to 20 days at a concentration of 15 μm in a micelle environment consisting of 1,2-diheptanoyl-sn-glycero-3-phosphocholine and n-dodecyl-ß-D-maltoside.
Power-Quality Improvement in PFC Bridgeless SEPIC-Fed BLDC Motor Drive
Authors: Singh Bhim , Bist Vashist
Published: July 2013

This article presents a design of a power factor correction (PFC)-based brushless DC (BLDC) motor drive. The speed control of BLDC motor is achieved by controlling the DC link voltage of the voltage source inverter (VSI) feeding BLDC motor using a single voltage sensor. A front-end bridgeless single-ended primary inductance converter (SEPIC) is used for DC link voltage control and PFC operation. A bridgeless SEPIC is designed to operate in discontinuous inductor current mode (DICM) thus utilizing a simple control scheme of voltage follower. An electronic commutation of BLDC motor is used for VSI to operate in a low-frequency operation for reduced switching losses in the VSI. Moreover, a bridgeless topology offers less conduction losses due to absence of diode bridge rectifier for further increasing the efficiency. The proposed BLDC motor drive is designed to operate over a wide range of speed control with an improved power-quality at the AC mains under the recommended international power-quality standards such as IEC 61000–3-2.