bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of a transmission model for dengue virus
Authors: Christofferson Rebecca C , McCracken Michael K , Johnson Ann-Marie , Chisenhall Daniel M , Mores Christopher N 
Published: April 2013

AbstractBackgroundDengue virus (DENV) research has historically been hampered by the lack of a susceptible vertebrate transmission model. Recently, there has been progress towards such models using several varieties of knockout mice, particularly those deficient in type I and II interferon receptors. Based on the critical nature of the type I interferon response in limiting DENV infection establishment, we assessed the permissiveness of a mouse strain with a blunted type I interferon response via gene deficiencies in interferon regulatory factors 3 and 7 (IRF3/7−/− −/−) with regards to DENV transmission success. We investigated the possibility of transmission to the mouse by needle and infectious mosquito, and subsequent transmission back to mosquito from an infected animal during its viremic period.MethodsMice were inoculated subcutaneously with non-mouse adapted DENV-2 strain 1232 and serum was tested for viral load and cytokine production each day. Additionally, mosquitoes were orally challenged with the same DENV-2 strain via artificial membrane feeder, and then allowed to forage or naïve mice. Subsequently, we determined acquisition potential by allowing naïve mosquitoes on forage on exposed mice during their viremic period.ResultsBoth needle inoculation and infectious mosquito bite(s) resulted in 100% infection. Significant differences between these groups in viremia on the two days leading to peak viremia were observed, though no significant difference in cytokine production was seen. Through our determination of transmission and acquisition potentials, the transmission cycle (mouse-to mosquito-to mouse) was completed. We confirmed that the IRF3/7−/− −/−mouse supports DENV replication and is competent for transmission experiments, with the ability to use a non-mouse adapted DENV-2 strain. A significant finding of this study was that this IRF3/7−/− −/−mouse strain was able to be infected by and transmit virus to mosquitoes, thus providing means to replicate the natural transmission cycle of DENV.ConclusionAs there is currently no approved vaccine for DENV, public health monitoring and a greater understanding of transmission dynamics leading to outbreak events are critical. The further characterization of DENV using this model will expand knowledge of key entomological, virological and immunological components of infection establishment and transmission events.
Total dietary fat and omega-3 fatty acids have modest effects on urinary sex hormones in postmenopausal women
Authors: Young Lindsay R , Raatz Susan K , Thomas William , Redmon J Bruce , Kurzer Mindy S 
Published: April 2013

Abstract

Background
Total fat and omega-3 fatty acids in the diet may affect breast cancer risk by altering estrogen metabolism. The purpose of this study was to elucidate the effects of differing total fat and omega-3 fatty acid content of diets on a panel of urinary estrogens and metabolites.

Findings
A controlled, cross-over feeding trial was conducted in postmenopausal women using three test diets: high fat diet (HF; 40% energy from fat), low fat diet (LF; 20% of energy from fat) and low fat, high omega-3 diet (LFn3; 23% energy from fat; 3% omega-3 fatty acids) for 8 week periods. Urinary hormone concentrations for 16 women were compared among diets using a linear mixed model, and within diet comparisons were made using paired t-tests. Urinary excretion of estrone was greater after the LF and LFn3 compared to the HF (P = 0.004). Estrone excretion was increased from baseline within the LF only (P = 0.02). Total estrone + estradiol + estriol increased from baseline with LF (P = 0.02) and was greater than the other two diets at 8 weeks (P = 0.03). There were no effects on estrogen metabolites, including the 2-hydroxy estrone:16α-hydroxy estrone ratio.

Conclusions
The results of this study indicate that urinary sex hormone metabolism was modestly altered in postmenopausal women by a low fat dietary intervention.
Bioactive compounds and antioxidant activity of Rosa canina L.biotypes from spontaneous flora of Transylvania
Authors: Roman Ioana , Stănilă Andreea , Stănilă Sorin 
Published: April 2013

Abstract

Background
The theoretical, but especially the practical values of identifying the biochemical compounds from the Rosa canina L. fruits are of present interest, this aspect being illustrated by the numerous researches. It was reported that the Rosa canina L. fruit, with its high ascorbic acid, phenolics and flavonoids contents, have antioxidant, antimutagenic and anticarcinogenic effects.
This study was performed on order to evaluate the amount of the main phytochemicals (vitamin C, total polyphenols, and total flavonoids) content and their antioxidant activity.

Results
The results obtained revealed that the average amounts of vitamin C within the studied genotypes were: 360.22 mg/100 g frozen pulp (var. transitoria f. ramosissima, altitude 1250 m) and 112.20 mg/100 g frozen pulp (var. assiensis, altitude 440 m), giving a good correlation between the vitamin C content of the rosehip and the altitude. The total polyphenols content varied from 575 mg/100 g frozen pulp (var. transitoria f. ramosissima) to 326 mg/100 g frozen pulp (var. lutetiana f. fallens). The total flavonoids content showed the highest value for var. assiensis variant 163.3 mg/100 g frozen pulp and the lowest value attributed to var. transitoria f. montivaga 101.3 mg/100 g frozen pulp. The antioxidant activity of eight rose hip extracts from wild Transylvania populations was investigated through DPPH method. The antioxidant activity revealed a good correlation only with vitamin C content and total polyphenols.

Conclusion
Eight Rose hip fruit species were compared taking into consideration the ascorbic acid, total polyphenols, total flavonoids contents and their antioxidant activity. Based on these results, two of the rosehip genotypes that were analysed could be of perspective for these species’ amelioration, due to their content of phytochemicals mentioned above. These varieties are var. transitoria f. ramosissima (Bistrita-Nasaud, Agiesel) and var. transitoria f. montivaga (Bistrita-Nasaud, Salva) which can be used as a potential source of natural antioxidants.
Life history and assessment of grapevine phylloxera leaf galling incidence on Vitis species in Uruguay
Authors: Vidart María Valeria , Mujica María Valentina , Bao Leticia , Duarte Felicia , Bentancourt Carlos María , Franco Jorge , Scatoni Iris Beatriz 
Published: April 2013

Abstract
Grapevine phylloxera, Daktulosphaira vitifoliae (Fitch) (Hemiptera: Phylloxeridae) is a worldwide pest of Vitis species. It has forms that feed on leaves and roots. Root forms predominate on Vitis vinifera (L.) cultivars, while leaf forms predominate on Vitis species from its native American range. Recently, high densities of D. vitifoliae infestations in leaves of V. vinifera in Brazil, Peru, and Uruguay have been reported. The aims of this study were to determine the seasonal development of grape phylloxera, quantify infestation levels on V. vinifera leaves, and compare them with infestation levels on leaves of a rootstock of American origin. Studies were conducted in two vineyards in Uruguay from 2004–2007. Terminal shoots of 3309 C and Cabernet Sauvignon, Chardonnay, Tannat, Viognier, grafted onto resistant rootstock, were sampled weekly and leaves examined for gall presence and insect life stage. First galls were detected in early October; eggs began to appear within two weeks. Two oviposition peaks occurred by the end of December, and they coincided with bursts of shoot growth. On 3309C rootstock, oviposition peaks were more frequent than on the European cultivars. Based on thermal accumulation, D. vitifoliae could complete eight generations a year in Uruguay. Rootstock 3309C suffered the greatest damage but in some cases was similar to the European cultivars. Damage to Chardonnay, Cabernet Sauvignon and Viognier were also high. There were no galls on Tannat. The 2005–2006 season was characterized by low infestation rates caused by a prolonged drought that affected vegetative growth. There were also differences between vineyards, where the vigorous plants suffering more damage. Leaf galling phylloxera incidence and damage were mainly associated to the cultivar but plant vigor and environmental factors also contributed to increase the incidence.
Engineering of chitosan and collagen macromolecules using sebacic acid for clinical applications
Authors: Sailakshmi G , Mitra Tapas , Gnanamani A 
Published: April 2013

Abstract
Transformation of natural polymers to three-dimensional (3D) scaffolds for biomedical applications faces a number of challenges, viz., solubility, stability (mechanical and thermal), strength, biocompatibility, and biodegradability. Hence, intensive research on suitable agents to provide the requisite properties has been initiated at the global level. In the present study, an attempt was made to engineer chitosan and collagen macromolecules using sebacic acid, and further evaluation of the mechanical stability and biocompatible property of the engineered scaffold material was done. A 3D scaffold material was prepared using chitosan at 1.0% (w/v) and sebacic acid at 0.2% (w/v); similarly, collagen at 0.5% (w/v) and sebacic acid at 0.2% (w/v) were prepared individually by freeze-drying technique. Analysis revealed that the engineered scaffolds displayed an appreciable mechanical strength and, in addition, were found to be biocompatible to NIH 3T3 fibroblast cells. Studies on the chemistry behind the interaction and the characteristics of the cross-linked scaffold materials suggested that non-covalent interactions play a major role in deciding the property of the said polymer materials. The prepared scaffold was suitable for tissue engineering application as a wound dressing material.
Differences in compliance with Surviving Sepsis Campaign recommendations according to hospital entrance time: day versus night
Authors: Almeida Mónica , Ribeiro Orquídea , Aragão Irene , Costa-Pereira Altamiro , Cardoso Teresa 
Published: April 2013

Abstract
Introduction
Higher compliance with Surviving Sepsis Campaign (SSC) recommendations has been associated with lower mortality. The authors evaluate differences in compliance with SSC 6-hour bundle according to hospital entrance time (day versus night) and its impact on hospital mortality.

Methods
Prospective cohort study of all patients with community-acquired severe sepsis admitted to the intensive care unit of a large university tertiary care hospital, over 3.5 years with a follow-up until hospital discharge. Time to compliance with each recommendation of the SSC 6-hour bundle was calculated according to hospital entrance period: day (08:30 to 20:30) versus night (20:30 to 08:30). For the same periods, clinical staff composition and the number of patients attending the emergency department (ED) was also recorded.

Results
In this period 300 consecutive patients were included. Compliance rate was (night vs. day): serum lactate measurement 57% vs. 49% (P = 0.171), blood cultures drawn 59% vs. 37% (P < 0.001), antibiotics administration in the first 3 hours 33% vs. 18% (P = 0.003), central venous pressure >8 mmHg 45% vs. 29% (P = 0.021), and central venous oxygen saturation (SvcO2) >70%, 7% vs. 2% (P = 0.082); fluids were administered in all patients with hypotension in both periods and vasopressors were administered in patients with hypotension not responsive to fluids in 100% vs. 99%. Time to get specific actions done was also different (night vs. day): serum lactate measurement (4.5 vs. 7 h, P = 0.018), blood cultures drawn (4 vs. 8 h, P < 0.001), antibiotic administration (5 vs. 8 h, P < 0.001), central venous pressure (8 vs. 11 h, P = 0.01), and SvcO2 monitoring (2.5 vs. 11 h, P = 0.222). The composition of the nursing team was the same around the clock; the medical team was reduced at night with a higher proportion of less differentiated doctors. The number of patients attending the Emergency Department was lower overnight. Hospital mortality rate was 34% in patients entering in the night period vs. 40% in those entering during the day (P = 0.281).

Conclusion
Compliance with SSC recommendations was higher at night. A possible explanation might be the increased nurse to patient ratio in that period. Adjustment of the clinical team composition to the patients' demand is needed to increase compliance and improve prognosis.
Specific Adverse Events Predict Survival Benefit in Patients Treated With Tamoxifen or Aromatase Inhibitors: An International Tamoxifen Exemestane Adjuvant Multinational Trial Analysis
Authors: Fontein Duveken B.Y. , Seynaeve Caroline , Hadji Peyman , Hille Elysée T.M. , van de Water Willemien , Putter Hein , Kranenbarg Elma Meershoek-Klein , Hasenburg Annette , Paridaens Robert J. , Vannetzel Jean-Michel , Markopoulos Christos , Hozumi Yasuo , Bartlett John M.S. , Jones Stephen E. , Rea Daniel William , Nortier Johan W.R. , van de Velde Cornelis J.H. 
Published: April 2013

Purpose Specific adverse events (AEs) associated with endocrine therapy and related to depletion or blocking of circulating estrogens may be related to treatment efficacy. We investigated the relationship between survival outcomes and specific AEs including vasomotor symptoms (VMSs), musculoskeletal adverse events (MSAEs), and vulvovaginal symptoms (VVSs) in postmenopausal patients with breast cancer participating in the international Tamoxifen Exemestane Adjuvant Multinational (TEAM) trial. Patients and Methods Primary efficacy end points were disease-free survival (DFS), overall survival (OS), and distant metastases (DM). VMSs, MSAEs, and VVSs arising in the first year of endocrine treatment were considered. Patients who did not start or who discontinued their allocated therapy and/or had an event (recurrence/death) within 1 year after randomization were excluded. Landmark analyses and time-dependent multivariate Cox proportional hazards models assessed survival differences up to 5 years from the start of treatment. Results A total of 9,325 patients were included. Patients with specific AEs (v nonspecific or no AEs) had better DFS and OS (multivariate hazard ratio [HR] for DFS: VMSs, 0.731 [95% CI, 0.618 to 0.866]; MSAEs, 0.826 [95% CI, 0.694 to 0.982]; VVSs, 0.769 [95% CI, 0.585 to 1.01]; multivariate HR for OS: VMSs, 0.583 [95% CI, 0.424 to 0.803]; MSAEs, 0.811 [95% CI, 0.654 to 1.005]; VVSs, 0.570 [95% CI, 0.391 to 0.831]) and fewer DM (VMSs, 0.813 [95% CI, 0.664 to 0.996]; MSAEs, 0.749 [95% CI, 0.601 to 0.934]; VVSs, 0.687 [95% CI, 0.436 to 1.085]) than patients not reporting these symptoms. Increasing numbers of specific AEs were also associated with better survival outcomes. Outcomes were unrelated to treatment allocation. Conclusion Certain specific AEs are associated with superior survival outcomes and may therefore be useful in predicting treatment responses in patients with breast cancer treated with endocrine therapy.
Terminal Spin Labeling of a High-mannose-type Oligosaccharide for Quantitative NMR Analysis of Its Dynamic Conformation
Authors: Yamaguchi Takumi , Kamiya Yukiko , Choo Yeun-Mun , Yamamoto Sayoko , Kato Koichi 
Published: April 2013

Abstract
To achieve quantitative conformational characterization of oligosaccharides possessing branched structures with internal mobility, we developed a paramagnetic tagging protocol for NMR relaxation analysis. A nitroxide spin label was attached chemically to the reducing terminus of a specific high-mannose-type undecasaccharide that was overexpressed in genetically engineered yeast cells. This hybrid approach provides a source of long-distance atomic information, enabling detailed characterization of the conformational dynamics of the triantennary sugar chain that is involved in protein-fate-determination processes in cells.
Triarylamine-conjugated Bis(terpyridine)–Iron(II) Complex Wires: Rapid and Long-range Electron-transport Ability
Authors: Sakamoto Ryota , Katagiri Shunsuke , Maeda Hiroaki , Nishihara Hiroshi 
Published: April 2013

Abstract
Bis(terpyridine)–iron(II) complex wires (the number of the complex units: 1–3) possessing triarylamine at the termini were fabricated on gold electrode. The electron-transfer rate constant between the triarylamine moiety and gold electrode was quantified by means of potential-step chronoamperometry, revealing that (1) triarylamine afforded fast electron transportation (i.e., large zero-distance rate constant ket0) and that (2) the distance attenuation factor, βd, was independent of the terminal redox site.
Measuring the Effect of Queues on Customer Purchases
Authors: Lu Yina , Musalem Andrés , Olivares Marcelo , Schilkrut Ariel 
Published: April 2013

We conduct an empirical study to analyze how waiting in queue in the context of a retail store affects customers' purchasing behavior. Our methodology combines a novel data set with periodic information about the queuing system (collected via video recognition technology) with point-of-sales data. We find that waiting in queue has a nonlinear impact on purchase incidence and that customers appear to focus mostly on the length of the queue, without adjusting enough for the speed at which the line moves. An implication of this finding is that pooling multiple queues into a single queue may increase the length of the queue observed by customers and thereby lead to lower revenues. We also find that customers' sensitivity to waiting is heterogeneous and negatively correlated with price sensitivity, which has important implications for pricing in a multiproduct category subject to congestion effects. This paper was accepted by Martin Lariviere, operations management.
What Are Investors Willing to Pay to Customize Their Investment Product?
Authors: Vrecko Dennis , Langer Thomas 
Published: April 2013

Even though buy-and-hold (B&H) investment strategies can take the risk tolerance of an investor into account by specifying a suitable stock proportion, the outcome profiles of B&H strategies are restricted to a specific class of return distributions. For investors with particular risk preferences, further customization should thus provide additional value. The objective of this paper is to investigate the strength of preference for such customized distributions and to draw conclusions about the demand for personalized investment products. In two experimental studies, 256 participants could adjust the return distribution of an initially chosen B&H investment by using an interactive software program. Our main finding is that most investors make extensive use of the customization option and many are willing to pay a substantial fee for this additional flexibility. We further find that the willingness to pay for customization is lower if the fee is integrated into the display of the return distribution, making its impact on final returns more obvious. We also observe that investors can be clustered into distinct subgroups via their adjustment patterns, but individually elicited prospect theory parameters are barely able to explain and predict these adjustments. As a robustness check, we also survey real investors at an investors fair to compare their preferences with those of our main pool of student subjects. We find that the willingness to pay for customization is slightly lower for these real investors and the main effect of fee integration is also less pronounced. In summary, we observe a strong willingness to pay for additional flexibility even though the actual benefits of customization vary markedly according to the individual. In many cases the accepted fees are so high that standard B&H strategies stochastically dominate the customized distributions after fee integration. This paper was accepted by Peter Wakker, decision analysis.
No-Arbitrage Taylor Rules with Switching Regimes
Authors: Li Haitao , Li Tao , Yu Cindy 
Published: April 2013

We study the time-varying nature of U.S. monetary policies summarized by the Taylor rule based on a continuous-time regime-switching term structure model. In this model, the spot rate follows the Taylor rule and government bonds at different maturities are priced by no arbitrage. We allow the coefficients of the Taylor rule and the dynamics of inflation and output gap to be regime dependent and estimate the model using government bond yields. We find that the Fed is proactive in controlling inflation in one regime and accommodative for growth in another. Moreover, proactive monetary policies are associated with more stable inflation and output gap and therefore could have contributed to the Great Moderation. Our analysis also highlights the importance of switching regimes for term structure modeling. Without the regimes, inflation and output can explain less than 50% of the variations of bond yields. With the regimes, the two variables can explain more than 80% of the variations of bond yields. This paper was accepted by Wei Xiong, finance.
Simple Auctions for Supply Contracts
Authors: Duenyas Izak , Hu Bin , Beil Damian R. 
Published: April 2013

This paper studies an optimal procurement mechanism for a newsvendor-like problem where the buyer's (newsvendor's) purchase price of the supplies is not fixed, but determined through interaction with candidate suppliers. The buyer has priors on the suppliers' costs but does not know their costs exactly. Recent literature has shown how the buyer can implement the optimal procurement mechanism by announcing a revenue function (specifying a payment for each quantity the buyer may purchase), then auctioning off the supply contract with the specified revenue function. In this paper, we show that a simple modified version of the standard open-descending auction for a fixed quantity is also an optimal mechanism for obtaining supplies. What distinguishes this mechanism is its simplicity and familiarity for the suppliers—open-descending auctions are very easy to run and ubiquitous in practice, whereas auctioning supply contracts with a specified revenue function is much less observed and more difficult to explain to suppliers. Furthermore, we show that this simple mechanism can be easily generalized to ex ante asymmetric suppliers and a class of nonlinear production costs. This paper was accepted by Yossi Aviv, operations management.
Two languages, two sets of interpretations: Language-specific influences of morphological form on Dutch and English speakers' interpretation of compounds
Authors: Banga Arina , Hanssen Esther , Schreuder Robert , Neijt Anneke 
Published: April 2013

AbstractThe present study investigates linguistic relativity. Do form differences between Dutch and English influence the interpretations which speakers have? The Dutch element en in noun-noun compounds, for example in aardbeienjam ‘strawberry jam’ is homophonous and homographic with the regular plural suffix -en. English, in contrast, has no such typical linking elements in compounds. We therefore investigated the interpretation of Dutch modifiers in compounds and their English equivalents. We compared the plurality ratings of Dutch modifiers with and without the linking element en by native Dutch speakers, and the plurality ratings of English modifiers by native Dutch speakers and native English speakers. If the Dutch linking en induces plural meaning, we expected a difference between the plurality ratings by English speakers for English modifiers and by Dutch speakers for Dutch modifiers, such that the estimation of the number of strawberries in strawberry jam is lower for the English speakers than the number of aardbeien in aardbeienjam for the Dutch speakers. This is exactly what we found. Moreover, when native Dutch speakers rate the English equivalents, their interpretation of strawberry jam is the same as for native English speakers, which shows the language being used to influence semantic interpretations.