bluuebunny/crossref_metadata_2025 huggingface dataset:
The asymptotic variance of departures in critically loaded queues
Authors: Al Hanbali A. , Mandjes M. , Nazarathy Y. , Whitt W.
Published: March 2011

We consider the asymptotic variance of the departure counting processD(t) of the GI/G/1 queue;D(t) denotes the number of departures up to timet. We focus on the case where the system load ϱ equals 1, and prove that the asymptotic variance rate satisfies limt→∞varD(t) /t= λ(1–2/π)(ca2+cs2), where λ is the arrival rate, andca2andcs2are squared coefficients of variation of the interarrival and service times, respectively. As a consequence, the departures variability has a remarkable singularity in the case in which ϱ equals 1, in line with the BRAVO (balancing reduces asymptotic variance of outputs) effect which was previously encountered in finite-capacity birth-death queues. Under certain technical conditions, our result generalizes to multiserver queues, as well as to queues with more general arrival and service patterns. For the M/M/1 queue, we present an explicit expression of the variance ofD(t) for anyt.
Limit theorems for supercritical age-dependent branching processes with neutral immigration
Authors: Richard M.
Published: March 2011

We consider a branching process with Poissonian immigration where individuals have inheritable types. At rate θ, new individuals singly enter the total population and start a new population which evolves like a supercritical, homogeneous, binary Crump-Mode-Jagers process: individuals have independent and identically distributed lifetime durations (nonnecessarily exponential) during which they give birth independently at a constant rateb. First, using spine decomposition, we relax previously known assumptions required for almost-sure convergence of the total population size. Then, we consider three models of structured populations: either all immigrants have a different type, or types are drawn in a discrete spectrum or in a continuous spectrum. In each model, the vector (P1,P2,…) of relative abundances of surviving families converges almost surely. In the first model, the limit is the GEM distribution with parameter θ /b.
Optimal Time to Exchange Two Baskets
Authors: Nishide Katsumasa , Rogers L. C. G.
Published: March 2011

In this paper we present simple extensions of earlier works on the optimal time to exchange one basket of log Brownian assets for another. A superset and subset of the optimal stopping region in the case where both baskets consist of multiple assets are obtained. It is also shown that a conjecture of Hu and Øksendal (1998) is false except in the trivial case where all the assets in a basket are the same processes.
Asymptotic Fluid Optimality and Efficiency of the Tracking Policy for Bandwidth-Sharing Networks
Authors: Avrachenkov Konstantin , Piunovskiy Alexey , Zhang Yi
Published: March 2011

Optimal control of stochastic bandwidth-sharing networks is typically difficult. In order to facilitate the analysis, deterministic analogues of stochastic bandwidth-sharing networks, the so-called fluid models, are often taken for analysis, as their optimal control can be found more easily. The tracking policy translates the fluid optimal control policy back to a control policy for the stochastic model, so that the fluid optimality can be achieved asymptotically when the stochastic model is scaled properly. In this work we study the efficiency of the tracking policy, that is, how fast the fluid optimality can be achieved in the stochastic model with respect to the scaling parameter. In particular, our result shows that, under certain conditions, the tracking policy can be as efficient as feedback policies.
Stochastic Comparison of Discounted Rewards
Authors: Righter Rhonda
Published: March 2011

It is well know that the expected exponentially discounted total reward for a stochastic process can also be defined as the expected total undiscounted reward earned before an independent exponential stopping time (let us call this the stopped reward). Feinberg and Fei (2009) recently showed that the variance of the discounted reward is smaller than the variance of the stopped reward. We strengthen this result to show that the discounted reward is smaller than the stopped reward in the convex ordering sense.
Building Multidimensional Biomarker Views of Type 2 Diabetes on the Basis of Protein Microheterogeneity
Authors: Borges Chad R , Oran Paul E , Buddi Sai , Jarvis Jason W , Schaab Matthew R , Rehder Douglas S , Rogers Stephen P , Taylor Thomas , Nelson Randall W
Published: March 2011

BACKGROUND

In 2008, the US Food and Drug Administration (FDA) issued a Guidance for Industry statement formally recognizing (during drug development) the conjoined nature of type 2 diabetes (T2D) and cardiovascular disease (CVD), which has precipitated an urgent need for panels of markers (and means of analysis) that are able to differentiate subtypes of CVD in the context of T2D. Here, we explore the possibility of creating such panels using the working hypothesis that proteins, in addition to carrying time-cumulative marks of hyperglycemia (e.g., protein glycation in the form of Hb A1c), may carry analogous information with regard to systemic oxidative stress and aberrant enzymatic signaling related to underlying pathobiologies involved in T2D and/or CVD.

METHODS

We used mass spectrometric immunoassay to quantify, in targeted fashion, relative differences in the glycation, oxidation, and truncation of 11 specific proteins.

RESULTS

Protein oxidation and truncation (owing to modified enzymatic activity) are able to distinguish between subsets of diabetic patients with or without a history of myocardial infarction and/or congestive heart failure where markers of glycation alone cannot.

CONCLUSION

Markers based on protein modifications aligned with the known pathobiologies of T2D represent a reservoir of potential cardiovascular markers that are needed to develop the next generation of antidiabetes medications.
Comparative Evaluation of the Moisture Permeation of Polyurethane, Polyethylene, and Fluoropolymer Tubing
Authors: Halper Sara R. , Villahermosa Randy M.
Published: March 2011

Polymer tubing is used for a variety of applications such as the transport of dry nitrogen and other gases in order to purge systems of moisture and other contaminants. While some polymer tubing are marketed for low-moisture applications, permeation data are often not reported to aid in material selection. Tests were performed to compare moisture permeation for a variety of tubing materials that could be used in dry gas purged systems. The results demonstrated that polyethylene and fluoropolymer tubing exhibited practically no moisture permeation, while polyurethane tubing exhibited a noticeable amount of moisture permeation. The results were compared with the moisture permeation of thin films. The permeation was found to be influenced by many factors as dictated by the various results derived from different brands and different durometers within the same brand. The effect of external relative humidity on permeation was also measured. Approximations can also be made on the internal relative humidity based on the external relative humidity. These approximations can be used as well to determine the maximum possible moisture exposure level outside the tubing or the purge time required for a specific application. The results could assist in material selection based on the desired application.
Truck Scheduling on Multicore
Authors: Pankratius Victor , Tichy Walter F.
Published: March 2011

Transportation businesses reduce costs by optimizing the routes of their trucks. However, determining optimal truck schedules is computationally intensive, running for hours on sequential computers. This article describes experience with parallelizing SAP´s Vehicle Scheduling and Routing Optimizer on shared-memory multicore computers. Re-engineering this complex application for a 24-core machine reduced typical computation time on real data from 1.5 hours to 5 minutes. The article discusses successful and unsuccessful parallelization approaches and concludes with lessons learnt.
Programming Techniques for the Cell Processor
Authors: Kessler Christoph
Published: March 2011

Cell Broadband Engine is a heterogeneous multicore processor designed mainly for applications in scientific computing, graphics, and gaming with high performance requirements. We give an overview of its architecture, review some selected development tools and programming frameworks, and describe techniques for writing efficient programs for Cell.
The influence of body mass index and renin–angiotensin–aldosterone system activity on the relationship between 25-hydroxyvitamin D and adiponectin in Caucasian men
Authors: Vaidya Anand , Forman John P , Underwood Patricia C , Hopkins Paul N , Williams Gordon H , Pojoga Luminita H , Williams Jonathan S
Published: March 2011

Objective

Previous studies have suggested that circulating adiponectin concentrations are associated positively with vitamin D and negatively with body mass index (BMI) but have not accounted for the influence of the renin–angiotensin–aldosterone system (RAAS) in this relationship. This is particularly relevant because increased RAAS activity is associated with obesity and is known to lower adiponectin levels. We evaluated the association between adiponectin and 25-hydroxyvitamin D (25(OH)D) after controlling RAAS activity with dietary sodium equilibration and also evaluated whether this relationship was influenced by BMI.

Design

Cross-sectional study of 115 hypertensive Caucasian men from the Hypertensive Pathotype Consortium.

Methods

To manipulate RAAS activity, all subjects underwent 1 week of high dietary sodium (HS) diet to suppress RAAS and 1 week of low dietary sodium (LS) diet to stimulate RAAS. Linear regression was used to evaluate the association between adiponectin and 25(OH)D, and the effect of BMI on this relationship, in each dietary condition.

Results

Adiponectin was higher on HS, where circulating RAAS activity was low, when compared with LS (HS=2.9 versus LS=2.4 μg/ml, P<0.0001). 25(OH)D levels were positively associated with adiponectin, and BMI was a statistically significant effect modifier of the relationship between 25(OH)D and adiponectin on both diets (P interaction <0.01 between BMI and 25(OH)D).

Conclusions

Higher 25(OH)D concentrations were independently associated with higher adiponectin levels, particularly when BMI was high. Dietary sodium balance and circulating RAAS activity did not appear to affect this relationship. Future studies should explore whether vitamin D supplementation increases adiponectin levels in obesity.
Recognizing Hypoglycemia in Children Through Automated Adverse-Event Detection
Authors: Dickerman Mindy J. , Jacobs Brian R. , Vinodrao Hima , Stockwell David C.
Published: March 2011

BACKGROUND:

Automated adverse-event detection using triggers derived from the electronic health record (EHR) is an effective method of identifying adverse events, including hypoglycemia. However, the true occurrence of adverse events related to hypoglycemia in pediatric inpatients and the harm that results remain largely unknown.

OBJECTIVE:

We describe the use of an automated adverse-event detection system to detect and categorize hypoglycemia-related adverse events in pediatric inpatients.

METHODS:

A retrospective observational study of all hypoglycemia triggers generated by an EHR-driven surveillance system was conducted at a large urban children's hospital during a 1-year period. All hypoglycemia triggers were investigated to determine if they represented a true adverse event and if that event followed or deviated from the local standard of care. Clinical and demographic variables were analyzed to identify subpopulations at risk for hypoglycemia.

RESULTS:

Of the 1254 hypoglycemia triggers produced, 198 were adverse events (positive predictive value: 15.8%). No hypoglycemic adverse events were identified via the hospital's voluntary incident-reporting system. The majority of hypoglycemia-related adverse events occurred in the NICU (n = 123 of 198 [62.1%]). A total of 154 (77.8%) of the 198 adverse events hospital-wide and 102 (83%) of the 123 adverse events in the NICU occurred in patients who were receiving insulin therapy.

CONCLUSIONS:

Hypoglycemia is common in hospitalized children, particularly neonates and those who receive insulin. An EHR-driven automated adverse-event detection system was effective in identifying hypoglycemia in this population. Automated adverse-event detection holds great promise in augmenting the safety program of organizations who have adopted the EHR.
The Medical Home: Health Care Access and Impact for Children and Youth in the United States
Authors: Strickland Bonnie B. , Jones Jessica R. , Ghandour Reem M. , Kogan Michael D. , Newacheck Paul W.
Published: March 2011

OBJECTIVE:

The medical home concept encompasses the elements of pediatric care considered essential for all children. We describe here the characteristics of children with medical homes and the relationship between presence of a medical home and selected health care outcomes by using new data from the 2007 National Survey of Children's Health (NSCH).

METHODS:

We used a medical home measure comprising 5 components: having a usual source of care; having a personal physician or nurse; receiving all needed referrals for specialty care; receiving help as needed in coordinating health and health-related care; and receiving family-centered care. A total of 83 448 children aged 1 to 17 years had valid data for all applicable medical home components. The NSCH is a random-digit-dial population-based telephone survey.

RESULTS:

In 2007, 56.9% of US children aged 1 to 17 years received care in medical homes. Younger children were more likely to have a medical home than their older counterparts. Substantial racial/ethnic, socioeconomic, and health-related disparities were present. Children who received care in medical homes were less likely to have unmet medical and dental needs and were more likely to have annual preventive medical visits.

CONCLUSIONS:

Approximately half of the children in the United States have access to all components of a pediatric medical home. Because the medical home is increasingly promoted as the standard for provision of high-quality comprehensive health care, these findings reinforce the need to continue and expand federal, state, and community efforts to ensure that all children have access to this model of care.
Nutrient Enrichment of Mother's Milk and Growth of Very Preterm Infants After Hospital Discharge
Authors: Zachariassen Gitte , Faerk Jan , Grytter Carl , Esberg Birgitte Hass , Hjelmborg Jacob , Mortensen Sven , Thybo Christesen Henrik , Halken Susanne
Published: March 2011

OBJECTIVE:

To determine if the addition of a multinutrient human milk fortifier to mother's milk while breastfeeding very preterm infants after hospital discharge is possible and whether it influences first-year growth.

METHODS:

Of a cohort of 320 infants (gestational age: 24–32 weeks; birth weight: 535–2255 g), breastfed infants (65% [n = 207]) were randomly assigned shortly before hospital discharge to receive either unfortified (n = 102, group A) or fortified (n = 105, group B) mother's milk until 4 months' corrected age (CA). The remaining infants were bottle-fed with a preterm formula (group C). Follow-up was performed at term and at 2, 4, 6, and 12 months' CA.

RESULTS:

Mean duration of breastfeeding after term was not significantly different between groups A and B (11.8 and 10.6 weeks, respectively). Weight, length, and head circumference were not significantly different between groups A and B at 12 months' CA. Compared with groups A and B, infants in group C had a higher increase in weight z score until term and in length z score until 6 months' CA. At 12 months' CA, boys in group C were significantly longer and heavier compared with those in groups A and B, whereas girls in group C were longer and heavier compared with those in group A only. A higher protein intake was related to a higher serum urea nitrogen level and growth.

CONCLUSIONS:

Fortification of mother's milk after hospital discharge while breastfeeding very preterm infants was possible without influencing breastfeeding duration but did not significantly influence growth parameters at 1 year of age compared with unfortified mother's milk.
Severe Vulvovaginitis as a Presenting Problem of Type 2 Diabetes in Adolescent Girls: A Case Series
Authors: Curran Jacqueline , Hayward Jenette , Sellers Elizabeth , Dean Heather
Published: March 2011

This article describes the presentation of 4 adolescent girls who sought medical attention for severe vulvovaginitis and were subsequently found to have type 2 diabetes. Symptomatic vulvovaginitis is rare in adolescent girls, and its presence should alert health care providers to test for underlying hyperglycemia. These 4 girls represent 8.5% of the females with new-onset type 2 diabetes during a 3-year period (2007–2009). The 4 cases fulfilled the current Canadian Diabetes Association screening criteria for type 2 diabetes in youth, yet none of these girls had been screened. These cases highlight the need for better awareness of screening criteria for type 2 diabetes in adolescents. Consideration should be given in clinical practice guidelines to including the presence of unusual or severe infections as a risk factor for type 2 diabetes in youth.
A Review of ERP Research: A Future Agenda for Accounting Information Systems
Authors: Grabski Severin V. , Leech Stewart A. , Schmidt Pamela J.
Published: March 2011

ABSTRACT: ERP systems are typically the largest, most complex, and most demanding information systems implemented by firms, representing a major departure from the individual and departmental information systems prevalent in the past. Firms and individuals are extensively impacted, and many problematic issues remain to be researched. ERP and related integrated technologies are a transformative force on the accounting profession. As the nature of business evolves, accounting expertise is being called on to make broader contributions such as reporting on nonfinancial measures, auditing information systems, implementing management controls within information systems, and providing management consulting services. This review of ERP research is drawn from an extensive examination of the breadth of ERP-related literature without constraints as to a narrow timeframe or limited journal list, although particular attention is directed to the leading journals in information systems and accounting information systems. Early research consisted of descriptive studies of firms implementing ERP systems. Then researchers started to address other research questions about the factors that lead to successful implementations: the need for change management and expanded forms of user education, whether the financial benefit outweighed the cost, and whether the issues are different depending on organizational type and cultural factors. This research encouraged the development of several major ERP research areas: (1) critical success factors, (2) the organizational impact, and (3) the economic impact of ERP systems. We use this taxonomy to establish (1) what we know, (2) what we need, and (3) where we are going in ERP research. The objective of this review is to synthesize the extant ERP research reported without regard to publication domain and make this readily available to accounting researchers. We organize key ERP research by topics of interest in accounting, and map ERP topics onto existing accounting information systems research areas. An emphasis is placed on topics important to accounting, including (but not limited to) the risk management and auditing of ERP systems, regulatory issues, the internal and external economic impacts of ERP systems, extensions needed in ERP systems for XBRL, for interorganizational support, and for the design of management control systems.

See Supplemental Material.
Analgesic drug administration and attitudes about analgesia in cattle among bovine practitioners in the United States
Authors: Fajt Virginia R. , Wagner Sarah A. , Norby Bo
Published: March 2011

Objective—To determine current attitudes and practices related to pain and analgesia in cattle among US veterinarians in bovine practice and to identify factors associated with these attitudes and practices.

Design—Web-based survey.

Sample—3,019 US members of the American Association of Bovine Practitioners (AABP) with e-mail addresses.

Procedures—Veterinarians were invited via e-mail to participate in a Web-based survey. Respondents replied to questions related to pain and analgesia and supplied personal, professional, and demographic information. Descriptive statistical analysis was performed, and associations among various factors were examined.

Results—666 surveys (25.5% response rate) were analyzed. Among common procedures and medical conditions of cattle listed on the survey, castration of dairy calves < 6 months old was subjectively estimated as causing the least pain; abdominal surgery, toxic mastitis, and dehorning of calves > 6 months old were assessed as causing the greatest pain. Respondents reported not providing analgesic drugs to approximately 70% of calves castrated at < 6 months of age. The most commonly administered analgesics were NSAIDs, local anesthetics, and α2-adrenergic receptor agonists. Significant associations were detected among respondent characteristics and pain ratings, percentages of cattle treated, and opinions regarding analgesia.

Conclusions and Clinical Relevance—Results provide information on current attitudes and practices related to pain and analgesia in cattle among US veterinarians in bovine practice and can be considered in the development of policies and protocols for pain management in cattle. These data can be compared with those of future studies to examine changes over time.
Predicting Antiretroviral Drug Resistance from the Latest or the Cumulative Genotype
Authors: Garcia Federico , Alvarez Marta , Fox Zoe , Garcia-Diaz Ana , Guillot Vicente , Johnson Margaret , Chueca Natalia , Phillips Andrew , Hernández-Quero José , Geretti Anna Maria
Published: March 2011

Background

This study evaluates the added benefit when estimating antiretroviral drug resistance of combining all available resistance test results in a cumulative genotype relative to using the latest genotype alone.

Methods

The prevalence of resistance and genotypic sensitivity scores (GSS) predicted by the latest and the cumulative genotype, together with virological outcomes after the latest genotype, were measured in treatment-experienced patients who underwent ≥2 resistance tests in 1999–2008.

Results

Comparing the latest with the cumulative genotype in 227 patients, 4 (1.7%) versus 0 (0.0%) showed no major resistance mutations, whereas 74 (32.6%) versus 46 (20.3%), 88 (38.8%) versus 76 (33.5%) and 61 (26.9%) versus 105 (46.3%) showed single-class, dual-class and triple-class resistance mutations, respectively. The median (IQR) number of fully or partially active drugs was 6 (5–6) versus 5 (4–6) for the nucleoside/nucleotide reverse transcriptase inhibitors, 3 (1–3) versus 1 (1–3) for the non-nucleoside reverse transcriptase inhibitors and 7 (7–7) versus 7 (7–7) for the protease inhibitors, respectively. Among 163 patients who started a new regimen after the latest genotype, both the latest and the cumulative GSS were predictive of early (≤24 weeks) virological responses. The GSS decreased by median 1 unit (IQR 0.5–1.0) in the cumulative genotype and larger differences relative to the latest genotype corresponded to smaller decreases in viral load.

Conclusions

The cumulative genotype offers a more comprehensive evaluation of the burden of resistance. This approach can guide small but appreciable improvements in the selection of antiretroviral regimens for treatment-experienced patients.
Study of human microecology by mass spectrometry of microbial markers
Authors: Osipov G. , Verkhovtseva N.
Published: March 2011

This review shows that mass spectrometry of microbial markers (MSMM) permits simultaneous in situ determination
of more than one hundred microbial fatty acids in clinical, biotechnological or environmental samples, without
precultivation and use of biochemical test materials and primers. Unprecedented information about the quantity of
anaerobes and uncultivated aerobes, as well as actinobacteria, yeasts, viruses and microscopic fungi in one sample has
provided a full understanding of microbial etiology in clinical conditions of patients. The study of intestine dysbiosis
has confirmed the hypothesis about the nosological specificity of changes in the intestinal microbiota. It has been
proven that infectious processes are polymicrobial. Measurements have shown that anaerobes dominate in number
and functional activities in inflammation. The division of microbes into pathogenic and non- pathogenic is artificial.
All microbes living in a human body simultaneously stay in both forms. Lactobacilli and bifidobacteria appear as
agents of septic conditions and endocarditis. МSММ data confirm that anaerobes of Clostridium, Eubacterium,
Propionibacterium, as well as actinobacteria of Streptomyces, Nocardia, Rhodococcus are mixed infection dominants.
The data testify translocation of these microbes in inflammation loci from the intestine. Quantitative comparison
of concentration of markers in the inflamed organ and blood proves reproduction of microorganisms in this locus.
The current hypothesis is confirmed that the goal of translocation is not only infection, but also a biofilm formation
similar to intestines, which stimulate local immunity, protection from local pathogens and restoration of the damaged
tissues. Quantification using GC-MS revealed that the influence of antibiotics on the normal intestine’s microbiota
are not as dramatic as believed. Growth-promoting effects are the most important benefits of probiotic applications.
The probiotic essence is not the microbial biomass itself, but growth factors, alarm molecules, and other factors of
intestinal microbes. There are new possibilities in improving probiotics by using microbial 'consortia', modelling
real gut microbiota.
Development of a molecularly imprinted polymer for patulin in apple juice
Authors: De Smet D. , Dubruel P. , Van Peteghem C. , De Saeger S.
Published: March 2011

The design of imprinted polymers selective towards patulin (PAT) and their application in food analysis are reported
for the first time. Different templates, functional monomers and molar ratios were evaluated related to binding
capacity and specificity. Besides the toxin itself, the implementation of structural analogues (2-hydroxynicotinic
acid, 5-indanol and 3-hydroxyphtalic anhydride) as templates was evaluated. A molecularly imprinted solid-phase
extraction (MISPE) procedure was optimised for the selective clean-up of apple juice samples. Depending on the
spiked concentration, recoveries after MISPE and non-imprinted solid-phase extraction varied respectively from
60% to 66% and from 40% to 41%. Limit of detection and limit of quantification were 10.0 µg/kg and 33.3 µg/kg,
respectively. Equilibrium experiments and Scatchard analysis disclosed the presence of two classes of binding sites
in the imprinted polymer. The dissociation constant (KD) of the higher affinity binding sites was 3.3 µmol/l, while
the KD of the lower affinity binding sites was 260.7 µmol/l. The performance of the molecularly imprinted polymer
throughout the clean-up was compared to liquid-liquid extraction and a C18 sorbent. Cross-reactivity experiments
demonstrated that MISPE was substantially more selective than C18 clean-up. Moreover chromatograms, with less
interfering peaks, were observed with MISPE resulting in a sensitive and reliable quantification of PAT.
Antioxidant activity, total phenolic, and total flavonoid of extracts from stems of Jasminum nervosum Lour
Authors: Huo Lini , Lu Rumei , Li Peiyuan , Liao Yanfang , Chen Rui , Deng Chaocheng , Lu Chengsheng , Wei Xiangyong , Li Yaohua
Published: March 2011

Guangxi traditional Chinese Medical University Universidad de Medicina Tradicional China de Guangxi This study evaluated the antioxidant activities of the extracts of Jasminum nervosum Lour. stems along with the effects of different extract solvents on total phenolics (TP), total flavonoids (TF), and antioxidant potential. The antioxidant activity of the extracts was assessed using the following methods: DPPH, ABTS+ both free radicals scavenging assays, and reducing assays. TP and TF were detected by spectrophotometric and HPLC methods. In former methods, the highest amount of TP content was ethy lacetate extract (EAE), expressed as gallic acid equivalents. The greatest TF content was in the n-butanol extract (BE), expressed as lutin equivalents. No significant difference was observed in the TP/TF content between these two extracts. The antioxidant activity and TP/TF content of three extracts seemed to follow the same trend. This implied that there is a good correlation between antioxidant activities and TP/TF content. But in HPLC methods, EAE contained the highest content of lutin and gallic acid, which decreased in the same order of EAE > BE > PE, the rank order of TP/TF content of EAE and BE were different according to antioxidant ability. The overall results showed that the EAE and BE were richer in phenolics and flavonoids than petroleum ether extract (PE), and may represent a good source of antioxidants.
High oleic sunflower biodiesel: quality control and different purification methods
Authors: Pighinelli Anna L.M.T. , Ferrari Roseli A. , Miguel Ana M.R.O. , Park Kil J.
Published: March 2011

The objective of the present work is to evaluate the production of biodiesel using ethanol and sunflower oil. The extraction of the sunflower oil was evaluated first. An experimental design was used to estimate the influence of the independent variables grain temperature (25º to 110ºC) and expeller rotation (85 to 119rpm) on the crude oil. The best result obtained was 68.38%, achieved with a rotation from 100 to 115rpm, grain temperature ranging from 25º to 30ºC and moisture content of around 7%. The next study consisted of transesterification, evaluating the influence of the ethanol, oil molar ratio and the catalyst concentration (sodium methylate) on the ester-rich phase yield. The highest yield was 98.39% obtained with a molar ratio of 9:1 and 3% catalyst. An experiment was then carried out on a small reactor and the biodiesel produced was purified by three different methods: acidified water, silica and distillation. The quality aspects of the purified biodiesel samples were evaluated according to the Brazilian specifications for biodiesel, and distillation was shown to be the best method of purification.
Oxidative stability of lard and sunflower oil supplemented with coffee extracts under storage conditions
Authors: Budryn Grażyna , Nebesny Ewa , Żyżelewicz Dorota
Published: March 2011

The oxidative stability of sunflower oil and lard supplemented with water extracts of green and roasted, Arabica and Robusta coffee beans was estimated. A decrease in the rate of fat oxidation reactions during the storage of samples for 12 weeks at ambient temperature which resulted from the addition of coffee extracts was evaluated using standard chemical methods such as the determination of peroxide and p-anisidine value and the assays of conjugated dienes and trienes as well as physical methods such as the determination of thermal profile by DSC. The sensory properties of all fat samples were also determined. These measurements showed that 0.1% water coffee extracts in fats decreased (p < 0.05) the quantities assayed by the chemical methods as compared to the control samples and approximately halved the rate of fat oxidation. In addition, the thermal profile analysis revealed that supplementing with coffee extracts reduced the extent of negative changes in the thermal properties of fats. The effectiveness of the tested coffee extracts decreased in the order: green Robusta > green Arabica > roasted Robusta > roasted Arabica.
Optimization and evaluation of wheat germ oil extracted by supercritical CO2
Authors: Jiang Shao Tong , Niu LiYa
Published: March 2011

Box-Behnken design combined with response surface methodology (RSM) was used to optimize the parameters of supercritical CO2 extraction (SFE) of wheat germ oil. The quality of the oil and residual meal obtained by SFE and solvent extraction (SE) were evaluated from proximate analysis, fatty acid composition and antioxidant activity. A maximum oil yield of 10.46% was achieved under the optimal conditions of wheat germ particle size 60-80 mesh; water content 4.37%; pressure 30MPa; temperature 40°C extraction time 1.7h. The oil obtained by SFE showed stronger DPPH radical scavenging ability than SE oil at the same concentration. The fatty acid composition of SFE oil was similar to SE oil. Higher contents of protein (34.3%) and lysine (2.47g/100g) were found in the residual meal obtained by SFE. The results show that oil and defatted meal obtained by SFE can be promising nutritional sources for food.
Wheat bran extracts: a potent source of natural antioxidants for the stabilization of canola oil
Authors: Shahid Chatha Shahzad Ali , Hussain Abdullah Ijaz , Bajwa Jawad-ur-Rehman , Hussain Sherazi Syed Tufail , Shaukat Aiza
Published: March 2011

In the present work, the antioxidant activity of different solvent extracts of wheat (var. Inqalab 91) bran was evaluated following different antioxidant assays using canola oil as the oxidation substrate. The bran samples were extracted with 80% and 100% methanol and acetone. A preliminary assessment of the antioxidant activity of the 80 and 100% acetone and methanolic extracts of wheat bran was done by the measurement of % inhibition of peroxidation in a linoleic acid system, total phenolic contents (TPC) and bleachability of β-carotene in the linoleic acid system. Additionally, the canola oil samples were stabilized with crude concentrated extracts and subjected to ambient aging (6 months). The extent of oxidative deterioration was followed by the measurement of peroxide-, p-anisidine-, conjugated dienes-, and trienes- values. The results of ambient stored samples revealed a significant improvement in these oxidation parameters. The overall order of antioxidant activity of the extracts as determined by various antioxidant assays was determined to be; 80% methanolic extract > 100% methanolic extract > 80% acetone extracts . 100% acetone extract. The results of the present comprehensive analysis demonstrate that extracts of the wheat bran indigenous to Pakistan are a viable source of natural antioxidants and might be exploited for commercial and neutraceutical applications.
Kinetics and thermodynamics of cottonseed oil extraction
Authors: Saxena Devesh K. , Sharma S. K. , Sambi S. S.
Published: March 2011

Petroleum derived n-hexane is commercially used in solvent extraction plants due to its higher extraction efficiency in spite of the fact that it is graded as highly toxic and hazardous. The present study is based on the use of both a much safer and non toxic solvent ethanol and n-hexane for the extraction of oil from cottonseed. The extraction data were obtained by varying temperature, solvent-solid ratio and particle size, to compare the extraction efficiency of both ethanol and n-hexane. The data show that nearly the same amount of extraction is possible at a higher solvent-solid ratio for both the solvents. This study has established that the kinetics of oil extraction follows a second order reaction mechanism. The thermodynamic analysis of the data shows that both ΔHº and ΔSº are positive, and ΔGº is negative indicating that the extraction process is endothermic, irreversible, and spontaneous.
IFN-α Mediates the Development of Autoimmunity both by Direct Tissue Toxicity and through Immune Cell Recruitment Mechanisms
Authors: Akeno Nagako , Smith Eric P. , Stefan Mihaela , Huber Amanda K. , Zhang Weijia , Keddache Mehdi , Tomer Yaron
Published: March 2011

IFN-α is known to play a key role in autoimmunity, but the mechanisms are uncertain. Although the induction of autoimmunity by IFN-α is consistent with primarily immunomodulatory effects, the high frequency of nonautoimmune inflammation suggests other mechanisms. We used thyroiditis as a model to dissect these possibilities. IFN-α treatment of cultured thyrocytes increased expression of thyroid differentiation markers, thyroglobulin, thyroid-stimulating hormone receptor, thyroid peroxidase, and sodium iodide transporter. RNAseq analysis demonstrated that pathways of Ag presentation, pattern recognition receptors, and cytokines/chemokines were also stimulated. These changes were associated with markedly increased nonapoptotic thyroid cell death, suggesting direct toxicity. To corroborate these in vitro findings, we created transgenic mice with thyroid-specific overexpression of IFN-α under control of the thyroglobulin promoter. Transgenic mice developed marked inflammatory thyroid destruction associated with immune cell infiltration of thyroid and surrounding tissues leading to profound hypothyroidism, findings consistent with our in vitro results. In addition, transgenic mice thyroids showed upregulation of pathways similar to those observed in cultured thyrocytes. In particular, expression of granzyme B, CXCL10, a subset of the tripartite motif-containing family, and other genes involved in recruitment of bystander cytotoxic immune responses were increased. Pathways associated with apoptosis and autophagy were not induced. Taken together, our data demonstrate that the induction of tissue inflammation and autoimmunity by IFN-α involves direct tissue toxic effects as well as provocation of destructive bystander immune responses.
Differential Requirements for Th1 and Th17 Responses to a Systemic Self-Antigen
Authors: Katzman Shoshana D. , Gallo Eugenio , Hoyer Katrina K. , Abbas Abul K.
Published: March 2011

T cell–APC interactions are essential for the initiation of effector responses against foreign and self-antigens, but the role of these interactions in generating different populations of effector T cells in vivo remains unclear. Using a model of CD4+ T cell responses to a systemic self-antigen without adjuvants or infection, we demonstrate that activation of APCs augments Th17 responses much more than Th1 responses. Recognition of systemic Ag induces tolerance in self-reactive CD4+ T cells, but induction of CD40 signaling, even under tolerogenic conditions, results in a strong, Ag-specific IL-17 response without large numbers of IFN-γ–producing cells. Transfer of the same CD4+ T cells into lymphopenic recipients expressing the self-antigen results in uncontrolled production of IL-17, IFN-γ, and systemic inflammation. If the Ag-specific T cells lack CD40L, production of IL-17 but not IFN-γ is decreased, and the survival time of recipient mice is significantly increased. In addition, transient blockade of the initial MHC class II-dependent T cell–APC interaction results in a greater reduction of IL-17 than of IFN-γ production. These data suggest that Th17 differentiation is more sensitive to T cell interactions with APCs than is the Th1 response, and interrupting this interaction, specifically the CD40 pathway, may be key to controlling Th17-mediated autoimmunity.
Usefulness of Hemodynamic Sensors for Physiologic Cardiac Pacing in Heart Failure Patients
Authors: Occhetta Eraldo , Bortnik Miriam , Marino Paolo
Published: March 2011

The rate adaptive sensors applied to cardiac pacing should respond as promptly as the normal sinus node with an highly specific and sensitive detection of the need of increasing heart rate. Sensors operating alone may not provide optimal heart responsiveness: central venous pH sensing, variations in the oxygen content of mixed venous blood, QT interval, breathing rate and pulmonary minute ventilation monitored by thoracic impedance variations, activity sensors. Using sensors that have different attributes but that work in a complementary manners offers distinct advantages. However, complicated sensors interactions may occur. Hemodynamic sensors detect changes in the hemodynamic performances of the heart, which partially depends on the autonomic nervous system-induced inotropic regulation of myocardial fibers. Specific hemodynamic sensors have been designed to measure different expression of the cardiac contraction strength: Peak Endocardial Acceleration (PEA), Closed Loop Stimulation (CLS) and TransValvular Impedance (TVI), guided by intraventricular impedance variations. Rate-responsive pacing is just one of the potential applications of hemodynamic sensors in implantable pacemakers. Other issues discussed in the paper include: hemodynamic monitoring for the optimal programmation and follow up of patients with cardiac resynchronization therapy; hemodynamic deterioration impact of tachyarrhythmias; hemodynamic upper rate limit control; monitoring and prevention of vasovagal malignant syncopes.
Artinianness of Certain Graded Local Cohomology Modules
Authors: Mafi Amir , Saremi Hero
Published: March 2011

We show that ifR= ⴲn∈ℕ0Rnis a Noetherian homogeneous ring with local base ring (R0, m0), irrelevant idealR+, andMa finitely generated gradedR-module, thenis Artinian forj= 0, 1 wheret= inf﹛i∈ ℕ0:is not finitely generated﹜. Also, we prove that if cd(R+,M) = 2, then for eachi∈ ℕ0,) is Artinian if and only ifis Artinian, where cd(R+,M) is the cohomological dimension ofMwith respect toR+. This improves some results of R. Sazeedeh.
Comunicación y cambio organizacional
Authors: Arras Vota Ana María , Jáquez Balderrama José Luis , Fierro Murga Luz Ernestina
Published: March 2011

La comunicación es un elemento esencial en la vida de las organizaciones, gracias e este proceso, a través del cual se ponen en común las experiencias y vivencias del ser humano, es posible que las personas realicen acciones conjuntas, generen acuerdos,  compromisos y participen en el cambio organizacional. En esta investigación se tiene como propósito analizar -a través de las circulares abiertas en forma de cartel- la influencia que tienen las comunicaciones como estrategias de poder en el cambio organizacional.
Improving catchment discharge predictions by inferring flow route contributions from a nested-scale monitoring and model setup
Authors: van der Velde Y. , Rozemeijer J. C. , de Rooij G. H. , van Geer F. C. , Torfs P. J. J. F. , de Louw P. G. B.
Published: March 2011

Abstract. Identifying effective measures to reduce nutrient loads of headwaters in lowland catchments requires a thorough understanding of flow routes of water and nutrients. In this paper we assess the value of nested-scale discharge and groundwater level measurements for the estimation of flow route volumes and for predictions of catchment discharge. In order to relate field-site measurements to the catchment-scale an upscaling approach is introduced that assumes that scale differences in flow route fluxes originate from differences in the relationship between groundwater storage and the spatial structure of the groundwater table. This relationship is characterized by the Groundwater Depth Distribution (GDD) curve that relates spatial variation in groundwater depths to the average groundwater depth. The GDD-curve was measured for a single field site (0.009 km2) and simple process descriptions were applied to relate groundwater levels to flow route discharges. This parsimonious model could accurately describe observed storage, tube drain discharge, overland flow and groundwater flow simultaneously with Nash-Sutcliff coefficients exceeding 0.8. A probabilistic Monte Carlo approach was applied to upscale field-site measurements to catchment scales by inferring scale-specific GDD-curves from the hydrographs of two nested catchments (0.4 and 6.5 km2). The estimated contribution of tube drain effluent (a dominant source for nitrates) decreased with increasing scale from 76–79% at the field-site to 34–61% and 25–50% for both catchment scales. These results were validated by demonstrating that a model conditioned on nested-scale measurements improves simulations of nitrate loads and predictions of extreme discharges during validation periods compared to a model that was conditioned on catchment discharge only.
Medicinal Inorganic Chemistry: Metallotherapeutics for Chronic Diseases
Authors: Thompson Katherine H.
Published: March 2011

Metal‐containing therapeutic agents designed for use in chronic disorders, such as gastrointestinal dyspepsia, bipolar disease, diabetes mellitus, osteoporosis, and arthritis, present additional challenges to the medicinal chemist. Beyond the immediate toxicity issues seen with acute disease treatments, chronic use of metallotherapeutic agents may result in metal ion accumulation or in gradually developing intolerance that can require discontinuation of the drug. Metallotherapeutic agents that have passed the rigorous testing required for chronic use include bismuth subsalicylates, for a variety of gastrointestinal disorders; lithium carbonate, for bipolar disease; lanthanum carbonate, for end‐stage renal disease; strontium ranelate, for osteoporosis; and the gold‐based antiarthritic, Auranofin™, although the last has fallen out of favor. Chromium picolinate is an approved nutritional supplement, a designation that allows less stringent testing than for new chronic‐use drugs. Among those compounds not currently approved for clinical use, but showing promise, the copper – indomethacin and zinc – indomethacin complexes, for inflammation resulting from rheumatoid arthritis; vanadium compounds, for glucose‐ and lipid‐lowering in type 2 diabetes mellitus; and selenium compounds, as possible cancer preventatives, are worthy of consideration.
Decorating
Authors: Collard Gene , Carpenter Robert
Published: March 2011

Decorating can be applied to plastics by heat‐transfer labeling, offset printing, hot stamping, screen process, pad‐transfer printing, painting, vacuum metallizing, electroplating, and various other coating methods. Various techniques and their implementation are reviewed.
Drying
Authors: McCormick P. Y.
Published: March 2011

Polymer drying is an important industrial operation employed to isolate the saleable product from the reaction process. Before melting and reextrusion for molding or spinning, many polymers have to be dried again because they are slightly hygroscopic and susceptible to degradation if melted in the presence of moisture. Terminology, psychrometry, drying mechanisms, drying operations, and other topics are covered. Examples of specific commercial polymers are presented.
Chemical Analysis
Authors: Rubinson Kenneth A.
Published: March 2011

This chapter outlines the tools of chemical analysis that are used to determine the identities and amounts of elements and molecules that comprise material—the usual solids, liquids, and gases but also including flames and interstellar matter and so forth. The choice of the method or instrument to be used depends on what fraction of the material to be measured is present in a material and the size of the sample. Current capabilities of analysis range from essentially unity (100%) to about one part in 10
12
. In addition, the complexity of samples encountered often dictates using a method that can isolate the responses from one or many species to be measured from those of the rest of the sample—a consideration that becomes more important when the fraction of the measured species the lower. Each method, tool, or instrument has its own characteristic abilities, and the choice of the best one can be quite involved.
Fundamental Constants
Authors: Flowers J. L. , Petley B. W.
Published: March 2011

We discuss the fundamental constants, considering their nature and definition as well as their experimental realization and use as measurement standards. We discuss the evaluations of the constants with emphasis on the 2006 evaluation. The proposed changes to the basis of the SI are considered as are some trends in scientific metrology.