bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the cost efficiency of mixing optimization
Authors: Gubanov Oleg , Cortelezzi Luca 
Published: December 2011

AbstractIn this study we discuss the cost efficiency of the optimization of a new prototypical mixing flow, the Fourier sine flow, an extension of the sine flow. The Fourier sine flow stirs a mixture on a two-dimensional torus by blinking, at prescribed switching times, two orthogonal velocity fields with profiles represented by a Fourier sine series. We derive a family of mixers of increasing complexity by truncating the series to one, two, three and four modes. We consider the optimization of the velocity profiles and the optimization of the stirring protocol. We implement the former by computing, at each iteration, the amplitudes and phase shifts of the Fourier modes synthesizing the velocity profiles that minimize the mix-norm, our cost function, i.e. maximize the quality of mixing. We implement the latter by selecting, at each iteration, the best performing of the two orthogonal stirring velocity fields, i.e. the velocity field that minimizes the mix-norm. To obtain a physically meaningful optimization problem, we constrain the kinetic energy of the flow to be the same among all mixers and use the viscous dissipation as an estimate of the power input needed to operate the mixers. We characterize the performance of the mixers using three cost functions: the homogenization time, the computational cost of optimization and the total energy consumption. We test the mixers on a range of admissible power inputs using two representative switching times. We report some surprising results. Mixers equipped with the velocity profile optimization and a periodic stirring protocol cannot be optimal, i.e. their performance depends on the switching time chosen, independently of the number of Fourier modes used in the optimization. Apparently, optimal mixers can be obtained only by coupling velocity profile and stirring protocol optimizations. The computational cost of the optimization depends only on the number of Fourier modes used and grows by about an order of magnitude for each Fourier mode added to the optimization. At low power inputs, the coupled optimizations allow us to obtain an attractive reduction of the homogenization time in combination with a reduction of the total energy required to produce it. However, increasing the power input does not guarantee a reduction of the homogenization time. Counter-intuitively, there are ranges of power inputs for which both the homogenization time and the total energy increase when increasing the power input. Finally, for large enough power inputs, optimizations with two, three and four Fourier modes perform similarly, making the former optimization the most cost-efficient.
Daily eating frequency and cardiometabolic risk factors in young Australian adults: cross-sectional analyses
Authors: Smith Kylie J. , Blizzard Leigh , McNaughton Sarah A. , Gall Seana L. , Dwyer Terence , Venn Alison J. 
Published: December 2011

Eating frequency may be important in the development of overweight and obesity and other cardiometabolic risk factors; however, the evidence is inconsistent. The aim of the present study was to examine the associations between the number of eating occasions and cardiometabolic risk factors in a national population-based sample of young adults. A cohort of 1273 men and 1502 women, aged 26–36 years, completed a meal pattern chart to record when they had eaten during the previous day (in hourly intervals). The total number of eating occasions was calculated. Diet quality was assessed, waist circumference was measured and a fasting blood sample was taken. Dietary intake was compared with the Australian Guide to Healthy Eating. The associations between the number of eating occasions and cardiometabolic risk factors were calculated using linear regression. Analyses were adjusted for age, education and physical activity. Most men ate three to five times per d and most women ate four to six times. The proportion of participants meeting dietary recommendations increased with the number of eating occasions. For men, an additional eating occasion was associated with reductions in mean values for waist circumference ( − 0·75 cm), fasting glucose ( − 0·02 mmol/l), fasting insulin ( − 0·34 mU/l; 2·04 pmol/l), TAG ( − 0·03 mmol/l), total cholesterol ( − 0·08 mmol/l) and LDL-cholesterol ( − 0·06 mmol/l). Adjustment for waist circumference attenuated the results. Significant trends were not observed for women. In conclusion, a higher number of eating occasions were associated with reduced cardiometabolic risk factors in men. Many associations were mediated by waist circumference.
Term Structure Estimation with Survey Data on Interest Rate Forecasts
Authors: Kim Don H. , Orphanides Athanasios 
Published: December 2011

AbstractThe estimation of dynamic no-arbitrage term structure models with a flexible specification of the market price of risk is beset by severe small-sample problems arising from the highly persistent nature of interest rates. We propose using survey forecasts of a short-term interest rate as an additional input to the estimation to overcome the problem. To illustrate the methodology, we estimate the 3-factor affine-Gaussian model with U.S. Treasury yields data and demonstrate that incorporating information from survey forecasts mitigates the small-sample problem. The model thus estimated for the 1990–2003 sample generates a stable and sensible estimate of the expected path of the short rate, reproduces the well-known stylized patterns in the expectations hypothesis tests, and captures some of the short-run variations in the survey forecast of the changes in longer-term interest rates.
Population trends of Critically Endangered Gyps vultures in the lowlands of Nepal
Authors: CHAUDHARY ANAND , SUBEDI TULSI RAM , GIRI JEET BAHADUR , BARAL HEM SAGAR , BIDARI BASU , SUBEDI HEM , CHAUDHARY BADRI , CHAUDHARY ISHWORI , PAUDEL KHADANANDA , CUTHBERT RICHARD J. 
Published: December 2011

SummaryThree species of resident Gyps vulture are threatened with extinction in South Asia due to the contamination of domestic ungulate carcasses with the drug diclofenac. Observed rates of population decrease are among the highest recorded for any bird species, leading to total declines in excess of 99.9% for the Oriental White-backed Vulture Gyps bengalensis in India between 1992 and 2007. Vultures have declined in Nepal, but quantitative information on the rate and scale of decreases is unavailable. Road transect surveys for vultures, following the same route, methodology and timing, were undertaken in lowland areas of Nepal for seven years from 2002 to 2011. The seven survey transects followed Nepal’s East-West highway and covered 1,010 km in three years of the survey, and 638 km in the remaining four years. Slender-billed Vultures G. tenuirostris were very scarce, with a maximum of five individuals in 2002 and none recorded in 2010 and 2011. Oriental White-backed Vultures were most commonly recorded, but decreased from 205 to 68 birds over the survey period, with an estimated annual rate of decline of 14% a year. If population decreases commenced in Nepal in the same year as in India, then White-backed Vultures in Nepal have declined by 91% since the mid-1990s. Few resident Gyps vultures remained in Eastern and Central regions of Nepal, with just one, nine and six birds recorded in the three surveys that covered these regions. The majority of threatened Gyps vultures in lowland Nepal are now found in Western and Mid Western regions, where conservation efforts have been focused in the last six years. Removing veterinary diclofenac from across the country and continuing to manage effective “vulture safe zones” are essential to conserve Nepal’s remaining vulture populations.
Variation in reproductive life-history traits of birds in fragmented habitats: a review and meta-analysis
Authors: VARGAS RENZO R. , FONTÚRBEL FRANCISCO E. , BONACORSO ELISA , SIMONETTI JAVIER A. 
Published: December 2011

SummaryThe effects of habitat fragmentation on the distribution and abundance of birds is a well-researched topic but there is little information published in terms of how habitat fragmentation affects reproductive life history traits. We reviewed the available literature on this subject and found that only 8% of the 1,433 studies dealing with birds in fragmented habitat studied life history traits and only 1.3% provided appropriate data to perform statistics. We found no effect of fragmentation on clutch and brood size patterns. Those patterns did not change when corrected by phylogeny. However, there is a significant heterogeneity among species responses, thus data on large-bodied, ground-nesting, and precocial birds suggest an increasing response in brood size in fragmented habitats. Finally, our review shows that despite birds being the most studied vertebrate group, crucial information such as the effects of habitat fragmentation on life history traits is still scarce and insufficient, especially on species of conservation concern. Indeed, only one out of 15 species reviewed here was threatened. Studies on reproductive, behavioural and life history trait variation are urgently needed in order to advance conservation actions.
Using a capture-recapture approach for modelling the detectability and distribution of Houbara Bustard in southern Tunisia
Authors: CHAMMEM M. , SELMI S. , KHORCHANI T. , NOUIRA S. 
Published: December 2011

SummaryModelling the distribution of species of conservation concern is an important issue in population ecology. Classically, logistic regression analyses are conducted to estimate species’ distributions from detection/non-detection data in a sample of sites and to test for the significance of several environmental variables in predicting the probability of occurrence. These modelling approaches assume that species detection probability is constant and equals one in all sampled sites, which is critical, notably in the case of rare, shy and cryptic species. The capture-recapture-like approach developed by Mackenzie et al. (2002, 2003) provides a reliable tool that accounts for imperfect detection when estimating species occurrence, as well as for assessing the relevance of site features as predictors of species occurrence probability. The aim of this study was to explore the possibility of using this approach in the context of Houbara Bustard Chlamydotis undulata in southern Tunisia. Our results show once more the low detectability of this emblematic species and stress the need to take this factor into account when estimating Houbara spatial distribution. The distribution of Houbara in southern Tunisia is more likely to be shaped by human-related than by habitat factors. In particular, Houbara occurrence was positively associated with site remoteness and camel numbers. Houbara seemed to avoid areas with high human presence and shared the most remote and agriculture-free zones with free-ranging camels.
Threatened birds of Guatemala: a random subset of the avifauna?
Authors: NÁJERA ANDREA , SIMONETTI JAVIER A. 
Published: December 2011

SummaryIdentifying attributes that affect the vulnerability of a species to extinction is important as it allows conservation efforts to be focused on more susceptible species. We assessed whether threatened birds of Guatemala are a random subset of the avifauna, considering their taxonomic affiliation, body size, diet and geographical distribution. We found that threatened bird species in Guatemala were neither taxonomically nor geographically randomly distributed. Large-bodied species and Psittaciformes, Galliformes, Falconiformes and Ciconiformes were among the most threatened groups, and the Pacific slopes of the country hosted more threatened birds than would be expected. Published scientific information regarding Critically Endangered bird species in Guatemala is scant and biased against nocturnal and aquatic species. Research and conservation efforts ought to be oriented toward these species and regions to safeguard the Guatemalan avifauna. This study allows an overall consideration on whether we are conserving the species and areas that are important for threatened birds.
Nasal Bacterial Microbiome: Probing a Healthy Porcine Family
Authors: Yue Min , Bei Weicheng , Chen Huanchun 
Published: December 2011

AbstractUpper respiratory tract (URT) infection caused the leading and devastating diseases in pigs. It was believed that the normal microbiome of URT plays a vital role in health and disease development. As the entry point of the URT, little knowledge of bacterial microbiome in porcine nasal was known. A cultivation-independent approach directly to 16s ribosomal RNA genes enabled us to reveal the nasal bacterial community, structure and diversity. Here, we found that an unprecedented 207 phylotypes were characterized from 933 qualified clones, indicating the variable, species richness but particularly dominant bacterial microbiome. The dominant species were from genus Comamonas and Acinetobacter, which constitute core normal bacterial microbiome in porcine nasal. Moreover, a set of swine specific pathogens and zoonotic agents were detected in the swine nasal microbiome. Collectively, we provided a snapshot of our current knowledge of the community structure of porcine nasal bacterial ecosystem in a healthy family that will further enhance our view to understand URT infection and public health.
Inhibition of acid‐sensing ion channels by amiloride protects rat articular chondrocytes from acid‐induced apoptosis via a mitochondrial‐mediated pathway
Authors: Rong Chao , Chen Fei‐Hu , Jiang Sheng , Hu Wei , Wu Fan‐Rong , Chen Tian‐Yi , Yuan Feng‐Lai 
Published: December 2011

AbstractA significant decrease in tissue pH or acidosis is a common feature of numerous diseases, including RA (rheumatoid arthritis). Cartilage homoeostasis is profoundly affected by local acidosis in the joints. The diuretic, amiloride, is neuroprotective in models of cerebral ischaemia, a property attributable to the inhibition of ASICs (acid‐sensing ion channels) by the drug. However, little is known about the effect of amiloride on apoptosis induced by extracellular acid in articular chondrocytes. We have found that amiloride could restrain the acid‐induced apoptosis of rat articular chondrocytes in vitro. Primary rat articular chondrocytes were isolated, cultured and induced to apoptose by exposure to extracellular solution (pH 6.0), while simultaneously treated with 50–200 μM amiloride. Apoptotic rate, mitochondrial function, levels of apoptosis‐related gene Bcl‐2 family mRNA and activity of caspase 3/9 in chondrocytes were examined. Amiloride inhibited chondrocyte apoptosis in a dose‐dependent manner. Furthermore, amiloride partly restored the levels of mitochondrial membrane potential by regulation of Bcl‐2 family gene mRNA expression, and activity of caspase 3/9 in chondrocytes induced by extracellular acid. Our results indicated that amiloride protected against acid‐induced apoptosis in rat articular chondrocytes by increasing anti‐apoptotic ability and down‐regulation of pro‐apoptotic factors, thus protecting mitochondrial function.
Use of Spectral/Cepstral Analyses for Differentiating Normal From Hypofunctional Voices in Sustained Vowel and Continuous Speech Contexts
Authors: Watts Christopher R. , Awan Shaheen N. 
Published: December 2011

PurposeIn this study, the authors evaluated the diagnostic value of spectral/cepstral measures to differentiate dysphonic from nondysphonic voices using sustained vowels and continuous speech samples.MethodologyThirty-two age- and gender-matched individuals (16 participants with dysphonia and 16 controls) were recorded reading a standard passage (The Rainbow Passage; Fairbanks, 1960) and sustaining the vowel /ɑ/. Recorded voices were analyzed with custom software that calculated 4 spectral/cepstral measures.ResultsMeasures of cepstral peak prominence (CPP) and low–high spectral ratio (L/H ratio) were significantly different between groups in both speaking conditions; the standard deviation of the CPP was significantly different between groups in continuous speech only. In differentiating dysphonic individuals with a hypofunctional etiology from nondysphonic individuals, receiver operating characteristic (ROC) analyses demonstrated (a) high sensitivity and high specificity for the CPP in the sustained vowel condition and (b) high sensitivity and moderate specificity for the CPP in the speech condition.ConclusionsIn a sample of dysphonic speakers (hypofunctional etiologies) versus typical speakers, spectral/cepstral measures of CPP and L/H ratio were able to differentiate these groups from one another in both vowel prolongation and continuous speech contexts with high sensitivity and specificity. The results of this study support the growing body of literature documenting the significant value of cepstral and other spectral-based acoustic measures to the clinical evaluation and management processes.
Topiramate for the treatment of methamphetamine addiction: a multi‐center placebo‐controlled trial
Authors: Elkashef Ahmed , Kahn Roberta , Yu Elmer , Iturriaga Erin , Li Shou‐Hua , Anderson Ann , Chiang Nora , Ait‐Daoud Nassima , Weiss David , McSherry Frances , Serpi Tracey , Rawson Richard , Hrymoc Mark , Weis Dennis , McCann Michael , Pham Tony , Stock Christopher , Dickinson Ruth , Campbell Jan , Gorodetzky Charles , Haning William , Carlton Barry , Mawhinney Joseph , Li Ming D. , Johnson Bankole A. 
Published: December 2011

ABSTRACTAims  Topiramate has shown efficacy at facilitating abstinence from alcohol and cocaine abuse. This double‐blind, placebo‐controlled out‐patient trial tested topiramate for treating methamphetamine addiction.Design  Participants (n = 140) were randomized to receive topiramate or placebo (13 weeks) in escalating doses from 50 mg/day to the target maintenance of 200 mg/day in weeks 6–12 (tapered in week 13). Medication was combined with weekly brief behavioral compliance enhancement treatment.Setting  The trial was conducted at eight medical centers in the United States.Participants  One hundred and forty methamphetamine‐dependent adults took part in the trial.Measurements  The primary outcome was abstinence from methamphetamine during weeks 6–12. Secondary outcomes included use reduction versus baseline, as well as psychosocial variables.Findings  In the intent‐to‐treat analysis, topiramate did not increase abstinence from methamphetamine during weeks 6–12. For secondary outcomes, topiramate reduced weekly median urine methamphetamine levels and observer‐rated severity of dependence scores significantly. Subjects with negative urine before randomization (n = 26) had significantly greater abstinence on topiramate versus placebo during study weeks 6–12. Topiramate was safe and well tolerated.Conclusions  Topiramate does not appear to promote abstinence in methamphetamine users but can reduce the amount taken and reduce relapse rates in those who are already abstinent.
Time pattern of reduction in risk of oesophageal cancer following alcohol cessation—a meta‐analysis
Authors: Jarl Johan , Gerdtham Ulf‐G. 
Published: December 2011

ABSTRACTAim  To establish the current level of knowledge of the effect of drinking cessation on the risk of developing oesophageal cancer.Method  A meta‐analysis was conducted based on relevant studies identified through a systematic literature review. A generalized least squares model for trend estimation of summarized dose–response data were utilized in order to estimate the effect of years since drinking cessation on risk of oesophageal cancer.Result  Seventeen studies that estimate the risk reduction after quantified drinking cessation were identified in the systematic literature review. Nine of these were appropriate for inclusion in the meta‐analysis. A large degree of heterogeneity existed between the studies, but this was explainable and the increased risk of oesophageal cancer caused by alcohol consumption was found to be reversible, with a common trend between studies. A required time‐period of 16.5 years (95% confidence interval 12.7–23.7) was estimated until no risk from former drinking remained, although this might have been an overestimation due to sample characteristics. The dose–response relationship was found to have an exponential decay. This means that about half the reduction in alcohol‐related risk occurred after just a third of the time‐period required to eliminate the additional risk.Conclusion  The alcohol‐related increased risk of oesophageal cancer is reversible following drinking cessation. It is most likely that about 16 years are required until all elevated risk has disappeared. Due to lack of research and data, more research is urgently required to increase the robustness of the estimates and to approach study limitations.
Forest phenology and a warmer climate – growing season extension in relation to climatic provenance
Authors: Gunderson Carla A. , Edwards Nelson T. , Walker Ashley V. , O'Hara Keiran H. , Campion Christina M. , Hanson Paul J. 
Published: December 2011

AbstractPredicting forest responses to warming climates relies on assumptions about niche and temperature sensitivity that remain largely untested. Observational studies have related current and historical temperatures to phenological shifts, but experimental evidence is sparse, particularly for autumn responses. A 4 year field experiment exposed four deciduous forest species from contrasting climates (Liquidambar styraciflua, Quercus rubra, Populus grandidentata, and Betula alleghaniensis) to air temperatures 2 and 4 °C above ambient controls, using temperature‐controlled open top chambers. Impacts of year‐round warming on bud burst (BB), senescence, and abscission were evaluated in relation to thermal provenance. Leaves emerged earlier in all species by an average of 4–9 days at +2 °C and 6–14 days at +4 °C. Magnitude of advance varied with species and year, but was larger for the first 2 °C increment than for the second. Effect of warming increased with early BB, favoring Liquidambar, but even BB of northern species advanced, despite temperatures exceeding those of the realized niche. Treatment differences in BB were inadequately explained by temperature sums alone. In autumn, chlorophyll was retained an average of 4 and 7 days longer in +2 and +4 °C treatments, respectively, and abscission delayed by 8 and 13 days. Growing seasons in the warmer atmospheres averaged 5–18 days (E2) and 6–28 days (E4) longer, according to species, with the least impact in Quercus. Results are compared with a 16 years record of canopy onset and offset in a nearby upland deciduous forest, where BB showed similar responsiveness to spring temperatures (2–4 days °C−1). Offset dates in the stand tracked August–September temperatures, except when late summer drought caused premature senescence. The common garden‐like experiment provides evidence that warming alone extends the growing season, at both ends, even if stand‐level impacts may be complicated by variation in other environmental factors.