bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gene silencing of mannose 6‐phosphate reductase in the parasitic weed Orobanche aegyptiaca through the production of homologous dsRNA sequences in the host plant
Authors: Aly Radi , Cholakh Hila , Joel Daniel M. , Leibman Diana , Steinitz Benjamin , Zelcer Aaron , Naglis Anna , Yarden Oded , Gal‐On Amit 
Published: May 2009

Summary Orobanche spp. (broomrape) are parasitic plants which subsist on the roots of a wide range of hosts, including tomato, causing severe losses in yield quality and quantity. Large amounts of mannitol accumulate in this parasitic weed during development. Mannose 6‐phosphate reductase (M6PR) is a key enzyme in mannitol biosynthesis, and it has been suggested that mannitol accumulation may be very important for Orobanche development. Therefore, the Orobanche M6PR gene is a potential target for efforts to control this parasite. Transgenic tomato plants were produced bearing a gene construct containing a specific 277‐bp fragment from Orobanche aegyptiaca M6PR‐mRNA, in an inverted‐repeat configuration. M6PR‐siRNA was detected in three independent transgenic tomato lines in the R1 generation, but was not detected in the parasite. Quantitative RT‐PCR analysis showed that the amount of endogenous M6PR mRNA in the tubercles and underground shoots of O. aegyptiaca grown on transgenic host plants was reduced by 60%–80%. Concomitant with M6PR mRNA suppression, there was a significant decrease in mannitol level and a significant increase in the percentage of dead O. aegyptiaca tubercles on the transgenic host plants. The detection of mir390, which is involved with cytoplasmic dsRNA processing, is the first indication of the existence of gene‐silencing mechanisms in Orobanche spp. Gene silencing mechanisms are probably involved with the production of decreased levels of M6PR mRNA in the parasites grown on the transformed tomato lines.
APPROXIMATING VOLATILITIES BY ASYMMETRIC POWER GARCH FUNCTIONS
Authors: Penzer Jeremy , Wang Mingjin , Yao Qiwei 
Published: May 2009

SummaryARCH/GARCH representations of financial series usually attempt to model the serial correlation structure of squared returns. Although it is undoubtedly true that squared returns are correlated, there is increasing empirical evidence of stronger correlation in the absolute returns than in squared returns. Rather than assuming an explicit form for volatility, we adopt an approximation approach; we approximate the γth power of volatility by an asymmetric GARCH function with the power index γ chosen so that the approximation is optimum. Asymptotic normality is established for both the quasi‐maximum likelihood estimator (qMLE) and the least absolute deviations estimator (LADE) in our approximation setting. A consequence of our approach is a relaxation of the usual stationarity condition for GARCH models. In an application to real financial datasets, the estimated values for γ are found to be close to one, consistent with the stylized fact that the strongest autocorrelation is found in the absolute returns. A simulation study illustrates that the qMLE is inefficient for models with heavy‐tailed errors, whereas the LADE is more robust.
ASSOCIATIONS BETWEEN AIR POLLUTION AND HOSPITAL VISITS FOR CARDIOVASCULAR DISEASES IN THE ELDERLY IN SYDNEY USING BAYESIAN STATISTICAL METHODS
Authors: Duc Hiep , Jalaludin Bin , Morgan Geoff 
Published: May 2009

SummaryUsing generalized linear models (GLMs), Jalaludin et al. (2006; J. Exposure Analysis and Epidemiology 16, 225–237) studied the association between the daily number of visits to emergency departments for cardiovascular disease by the elderly (65+) and five measures of ambient air pollution. Bayesian methods provide an alternative approach to classical time series modelling and are starting to be more widely used. This paper considers Bayesian methods using the dataset used by Jalaludin et al. (2006), and compares the results from Bayesian methods with those obtained by Jalaludin et al. (2006) using GLM methods.
A Poole Analysis in the New Open Economy Macroeconomic Framework*
Authors: Hoffmann Mathias , Kempa Bernd 
Published: May 2009

AbstractThis paper evaluates simple monetary policy rules in the tradition of the Poole analysis within a general two‐country model for a large economy and a small open economy. The results for the large economy resemble those of the original Poole scenario and also extend to the welfare measure. In particular, an interest rate rule is preferable to a money supply rule when liquidity shocks dominate, whereas a money supply rule fares better with real shocks. For the small open economy, the stabilization properties of the large‐economy case continue to hold for domestic shocks, but a money supply rule performs better than an interest rate rule using the welfare measure. If shocks originate in the foreign economy, a money supply rule turns out to be superior both in terms of its stabilization properties as well as in terms of welfare.
Time Zones as a Source of Comparative Advantage
Authors: Kikuchi Toru 
Published: May 2009

AbstractThis note proposes a three‐country model of monopolistic competition that captures the role of time zones in the division of labor. The connectivity of business service sectors via communications networks (e.g. the Internet, satellite communications systems) is found to determine the structure of comparative advantage. That is, two countries with connected service sectors have a comparative advantage in the good that requires business services. It is also shown that the third unconnected country inevitably specializes in the good that does not require business services.
Exports to Smuggle and Smuggling Technologies*
Authors: Larue Bruno , Pouliot Sébastien , Constantatos Christos 
Published: May 2009

AbstractOur analysis is motivated by cases of cigarette smuggling in Canada and in the UK. In the 1990s, domestic cigarettes were legally exported to be subsequently illegally imported. At first, smuggling was done by individual consumers who bought cigarettes abroad and brought them back through policed points of entry. This Mom and Pop smuggling was a mechanism to implement a second‐degree price discrimination scheme by cigarette manufacturers. Regrets from committing tax evasion and labels on exported cigarettes packs permit vertical differentiation of illegal and legal cigarettes. Paradoxically, labeling measures can make illegal sales more resilient to tax reductions, and stricter border enforcement encourages a switch to a less benign smuggling technology exclusive to criminal organizations. High export taxes terminated export‐to‐smuggle schemes, but brought about a surge of counterfeit cigarettes. Because of a second‐degree price discrimination scheme, the elimination of taxes need not suffice to eradicate smuggling.
International Technology Transfers and Competition*
Authors: Feess Eberhard , Hoeck Michael , Lorz Oliver 
Published: May 2009

AbstractThis paper analyzes North–South technology transfers in a model of oligopolistic competition and spatial product differentiation. Two firms in the North supply a high‐tech good and a technically related low‐tech good. They decide about licensing the low‐tech good to suppliers in the South. With the license Southern firms get access to technology from the North, which enables them—with a certain probability—to enter the market for the high‐tech good. Northern firms may therefore license strategically to influence the competitive environment in the high‐tech market. In this setting, multiple equilibria with and without licensing may arise, and the resulting outcomes may be inefficient from the viewpoint of the Northern firms.
Analysing the Gender Wage Gap (GWG) Using Personnel Records
Authors: Pfeifer Christian , Sohr Tatjana 
Published: May 2009

AbstractWe use monthly personnel records of a large German company for the years 1999–2005 to analyse the gender wage gap (GWG). The unconditional GWG is 15 per cent for blue‐collar and 26 per cent for white‐collar workers. Different returns to entry age explain a substantial part of the GWG as well as segregation of men and women in different hierarchical levels. The relative GWG increases with increasing tenure for blue‐collar but declines for white‐collar workers. Taking into account the different impact of general and firm‐specific human capital on white‐collar and blue‐collar occupation, this is consistent with theories of statistical discrimination.
The phosphorus requirement ofAmaranthus mangostanusL. exceeds the ‘change point’ of P loss
Authors: Liang L. Z. , Shen R. F. , Yi X. Y. , Zhao X. Q. , Chen Z. C. , Chen R. F. , Dong X. Y. 
Published: May 2009

AbstractDue to the high economic value of vegetables, farmers in China often apply more fertilizer than is required for plant growth. This leads to phosphorus accumulation in soils, which can pollute the aquatic environment. This conflict arises because vegetables often use nutrients inefficiently, and require high phosphorus levels in the growth medium. In this study, amaranth (Amaranthus mangostanusL.) was grown in soils with 14.7, 23.8, 45.3, 54.6, 74.2, 101 or 116 mg Olsen‐P/kg, and with and without phosphorus fertilizer (175 mg P/kg or equivalent to 385 kg P/ha). The yield of amaranth was positively correlated with soil Olsen‐P content. CaCl2‐P content was positively correlated with Olsen‐P content and CaCl2‐P markedly increased at Olsen‐P contents exceeding 53.8 mg P/kg in the pot experiment or 55.9 mg P/kg in the field survey. These values were regarded as the ‘change points’ for phosphorus loss; to achieve 85 or 95% of maximum amaranth yield, the amaranth crop required 91or 101 mg Olsen‐P/kg soil, respectively, and application of 175 mg P/kg was still able to significantly increase amaranth yield at an Olsen‐P level of 74.2 mg P/kg soil. These results indicated that the phosphorus requirement of amaranth exceeded the ‘change point’ (53.8 or 55.9 mg Olsen‐P/kg); theCmin(minimum concentration in the media at which no net influx occurs) of phosphorus for 3‐week‐old amaranth was 1.55 μm. This value is much higher than that reported for other crops, and may explain the inefficient P use of amaranth. The highCminvalue also indicates that the phosphorus requirement of amaranth is beyond the ‘change point’ of P loss.
Clovamide and rosmarinic acid induce neuroprotective effects inin vitromodels of neuronal death
Authors: Fallarini S , Miglio G , Paoletti T , Minassi A , Amoruso A , Bardelli C , Brunelleschi S , Lombardi G 
Published: May 2009

Background and purpose: Phenolic compounds exert cytoprotective effects; our purpose was to investigate whether the isosteric polyphenolic compounds clovamide and rosmarinic acid are neuroprotective.Experimental approach: Threein vitromodels of neuronal death were selected: (i) differentiated SH‐SY5Y human neuroblastoma cells exposed totert‐butylhydroperoxide (t‐BOOH), for oxidative stress; (ii) differentiated SK‐N‐BE(2) human neuroblastoma cells treated with L‐glutamate, for excitotoxicity; and (iii) differentiated SH‐SY5Y human neuroblastoma cells exposed to oxygen‐glucose deprivation/reoxygenation, for ischaemia–reperfusion. Cell death was evaluated by lactate dehydrogenase measurements in the cell media, while the mechanisms underlying the effects by measuring: (i)t‐BOOH‐induced glutathione depletion and increase in lipoperoxidation; and (ii) L‐glutamate‐induced intracellular Ca2+overload (fura‐2 method) and inducible gene expression (c‐fos,c‐jun), by reverse transcriptase‐PCR. The ability of compounds to modulate nuclear factor‐κB and peroxisome proliferator‐activated receptor‐γ activation was evaluated by Western blot in SH‐SY5Y cells not exposed to harmful stimuli.Key results: Both clovamide and rosmarinic acid (10–100 µmol·L−1) significantly protected neurons against insults with similar potencies and efficacies. The EC50values were in the low micromolar range (0.9–3.7 µmol·L−1), while the maximal effects ranged from 40% to −60% protection from cell death over untreated control at 100 µmol·L−1. These effects are mediated by the prevention of oxidative stress, intracellular Ca2+overload andc‐fosexpression. In addition, rosmarinic acids inhibited nuclear factor‐κB translocation and increased peroxisome proliferator‐activated receptor‐γ expression in SH‐SY5Y cells not exposed to harmful stimuli.Conclusion and implications: Clovamide and rosmarinic acid are neuroprotective compounds of potential use at the nutritional/pharmaceutical interface.
Second‐hand cigarette smoke inhibits wound healing of the cornea by stimulating inflammation that delays corneal reepithelialization
Authors: Ma Chongze , Martins‐Green Manuela 
Published: May 2009

ABSTRACTCorneal reepithelialization is a key process in preventing abnormal cornea healing and impaired vision. To gain insight into the mechanisms of cigarette smoke‐induced corneal epithelial damage, we injured the cornea of mice and exposed the wounds during the healing process to cigarette smoke in a system that mimics second‐hand cigarette smoking by humans. Immunolabeling studies showed that in the mice exposed to smoke, fibronectin, an extracellular matrix molecule critical for epithelial cell migration, is not present in the wounded area and that there is an accumulation of neutrophils in the stroma beneath the wound. Furthermore, inflammatory cytokines, such as interleukin‐1α, increase after injury in the second‐hand‐smoke‐exposed mice. Localized treatment of the wounds with dexamethasone, an anti‐inflammatory agent, resulted in improved healing and infiltration of fewer neutrophils into the wounded area. Depletion of neutrophils with nitrogen mustard or treatment of the wounds with proteinase inhibitors have similar effects to those of dexamethasone. In conclusion, the work presented here shows that second‐hand cigarette smoke delays corneal reepithelialization and healing by stimulating both neutrophil attraction to the wound site and degradation of extracellular matrix and adhesion molecules that are important for corneal epithelial cell adhesion and migration.
Mice lacking β6 integrin in skin show accelerated wound repair in dexamethasone impaired wound healing model
Authors: Xie Yanshuang , Gao Kai , Häkkinen Lari , Larjava Hannu S. 
Published: May 2009

ABSTRACTIntegrin αvβ6 is an epithelial‐specific receptor that is absent from the healthy epidermis but synthesized de novo during wound repair. However, its function in wound repair is unknown. Integrin‐mediated transforming growth factor‐β1 (TGF‐β1) activation is the main activation mechanism of this key cytokine in vivo. Impaired wound healing caused by glucocorticoids is a major clinical problem and is associated with a disturbed balance of TGF‐β1 activity. Therefore, αvβ6 integrin‐mediated regulation of TGF‐β1 activity may be involved in this process. To determine the function of αvβ6 integrin in glucocorticoid‐induced impaired wound healing, both β6 integrin‐deficient (β6−/−) and wild‐type mice were exposed to dexamethasone treatment. Multiple wound parameters, keratinocyte proliferation, inflammation, and TGF‐β1 activation were assessed. Wound healing was significantly accelerated in the dexamethasone‐treated β6−/− mice compared with the corresponding wild‐type mice. The dexamethasone‐treated β6−/− mice showed enhanced keratinocyte proliferation in both wound epithelium and hair follicles while the production of proinflammatory cytokines and TGF‐β1 activation were reduced. Accelerated wound repair in the dexamethasone‐treated β6−/− mice might be associated with the reduced antiproliferative and proinflammatory effects of TGF‐β1. Inhibition of αvβ6 integrin may provide a future target for treatment of impaired wound healing.
Consequences of surgical stress on the kinetics of skin wound healing: Partial hepatectomy delays and functionally alters dermal repair
Authors: Sorg Heiko , Schulz Torsten , Krueger Christian , Vollmar Brigitte 
Published: May 2009

ABSTRACTThe objective was to determine the significance of surgical trauma in dermal wound healing. Using intravital microscopy, we analyzed the healing kinetics of full‐thickness dermal wounds in the ears of SKH1 mice. Partial hepatectomy (pHx) simulated major surgical trauma, while laparotomy only served as a sham operation (sham). Animals without abdominal surgery served as controls (control). Laparotomy wounds were analyzed for biomechanical qualities and collagen deposition. Morphological characterization of skin repair was performed by histology/immunohistochemistry. In vitro cell assays assessed the paracrine effects of surgical stress. PHx caused a transient increase in tumor necrosis factor‐alpha (TNF‐α) and interleukin (IL)‐6 levels and led to weight loss, reflecting the host's overall response to surgery. Wound closure in pHx animals was delayed vs. control and sham animals, as indicated by significantly lower values of epithelialization and neovascularization over 10 days. Ear wound histology further revealed a provisional wound matrix with a reduced microvessel density. Moreover, pHx‐laparotomy wounds showed a reduced bursting strength coexisting with significantly decreased collagen content. PHx and sham serum caused a significant alteration in in vitro fibroblast viability. Skin healing is dependent on the extent of surgery and is influenced by its paracrine effects. Therefore, considerable effort should be focused on the development of strategies limiting surgery‐associated perturbations of dermal repair.
A functional model for adult stem cells in epithelial tissues
Authors: Verstappen Jochem , Katsaros Christos , Torensma Ruurd , Von den Hoff Johannes W. 
Published: May 2009

ABSTRACTTissue turnover, regeneration, and repair take place throughout life. Stem cells are key players in these processes. The characteristics and niches of the stem cell populations in different tissues, and even in related tissues, vary extensively. In this review, stem cell differentiation and stem cell contribution to tissue maintenance and regeneration is compared in the epithelia of the skin, the cornea, the lung, and the intestine. A hierarchical model for adult stem cells is proposed, based on the potency of stem cell subpopulations in a specific tissue. The potency is defined in terms of the maintenance, the repair, and the regeneration of the tissue. The niche supplies cues to maintain the specific stem cell potency.
Heart Disease Risk Factors in Midlife Predict Subclinical Coronary Atherosclerosis More than 25 Years Later in Survivors without Clinical Heart Disease: The Rancho Bernardo Study
Authors: Barrett‐Connor Elizabeth , Bergstrom Jacqueline , Wright C. Michael , Kramer Caroline K. 
Published: May 2009

OBJECTIVES: To determine which of the classic modifiable coronary heart disease (CHD) risk factors, measured in midlife, are associated with subclinical coronary atherosclerosis in older age.DESIGN: Prospective study.SETTING: Community based.PARTICIPANTS: Participants were 400 community‐dwelling middle‐aged adults who had no history of CHD at baseline (1972–1974), when CHD risk factors were measured, and who were still free of known CHD in 2000 to 2002.MEASUREMENTS: Coronary artery plaque burden was assessed according to coronary artery calcium (CAC) score using computed tomography in 2000 to 2002.RESULTS: Ordinal logistic regression analysis was used to compare baseline risk factors with severity of CAC. Mean age was 42 at baseline and 69 at the time of CAC assessment; 46.5% were male. In analyses adjusted for age, sex, and all other risk factors, one standard deviation increase in body mass index (odds ratio (OR)=1.24, 95% confidence interval (CI)=1.02–1.51; P=.03), cholesterol (OR=1.28, 95% CI=1.03–1.58; P=.020, pulse pressure (OR=1.24, 95% CI=1.03–1.50; P=.03), and log triglycerides (OR=1.22, 95% CI=0.99–1.50; P=.06) each independently predicted the presence and severity of coronary artery atherosclerosis.CONCLUSION: Modifiable risk factors measured more than 25 years earlier influence plaque burden in elderly survivors without clinical heart disease.
Complications of Atrial Fibrillation Ablation in a High‐Volume Center in 1,000 Procedures: Still Cause for Concern?
Authors: DAGRES NIKOLAOS , HINDRICKS GERHARD , KOTTKAMP HANS , SOMMER PHILIPP , GASPAR THOMAS , BODE KERSTIN , ARYA ARASH , HUSSER DANIELA , RALLIDIS LOUKIANOS S. , KREMASTINOS DIMITRIOS TH. , PIORKOWSKI CHRISTOPHER 
Published: May 2009

Introduction:
Catheter ablation is potentially curative treatment for atrial fibrillation (AF). However, complications are more frequent and more severe compared with other ablation procedures. We investigated the complication rate in 1,000 AF ablation procedures in a high‐volume center and examined possible risk factors.
Methods and Results:
One thousand consecutive circumferential pulmonary vein radiofrequency ablations were performed for symptomatic, drug‐refractory AF. Major complications were defined as the ones that were life threatening, caused permanent harm, and required intervention or prolonged hospitalization. Thirty‐nine (3.9%) major periprocedural complications were observed. There was no death immediately associated with the procedure. However, there were 2 deaths (0.2%) of unclear cause, 14 days and 4 weeks after ablation. The most common complications were tamponade (1.3%), treated mainly by percutaneous drainage, and vascular complications (1.1%). There were also 4 thromboembolic events (0.4%): 3 nonfatal strokes and one transient ischemic attack. Importantly, 2 cases (0.2%) of atrial‐esophageal fistula and 2 cases (0.2%) of endocarditis were observed. Factors associated with an increased complication risk were age ≥75 years (hazard ratio 3.977, P = 0.022) and congestive heart failure (hazard ratio 5.174, P = 0.001).
Conclusion:
AF ablation still has a considerable number of major complications that may be life threatening or may lead to severe residues. Atrial‐esophageal fistula is still observed despite continuous systematic methods to prevent it. Stroke, tamponade, and vascular complications are the most frequent major complications. However, in most patients treatment can be conservative and results in complete recovery. Advanced age and congestive heart failure seem to be associated with an increased risk of complications.
Effects of maize (Zea mays L.) silage feeding on dry matter intake and milk production of dairy buffalo and cattle in Tarai, Nepal
Authors: HAYASHI Yoshiaki , THAPA Bhim B. , SHARMA Mohan P. , SAPKOTA Maheshwor , KUMAGAI Hajime 
Published: May 2009

ABSTRACTTo identify the effects of whole crop maize silage (MS) as a substitute for rice straw (RS) on feed intake and milk production of mid‐late lactating buffalo and cattle in Tarai, Nepal, eight Murrah and eight Jersey‐Hariana were fed the basal diet, RS (ad libitum) with concentrate (0.68% of bodyweight [BW] on a dry matter [DM] basis). A 4 × 4 Latin square design experiment was conducted in each animal species with graded levels of MS substitution for RS (0%, T1; 33%, T2; 67%, T3 and 100%, T4). The MS had higher digestibility and total digestible nutrient (TDN) than RS. The DM intake per BW of the both species was highest in T3. The substitution of MS for RS increased the crude protein intake and the TDN intake in the both species. Although the buffalo showed the highest milking performance in T4, the cattle showed no significant differences in their milking performance among the treatments. The substitution of MS for RS improved the feed intake and milk production in the buffalo. On the other hand, the milk yield was not raised in the cattle, though the feed intake was increased by the substitution.