bluuebunny/crossref_metadata_2025 huggingface dataset:
Effective age models for imperfect maintenance
Authors: Labeau P-E , Segovia M-C
Published: July 2011

A large number of maintenance models are available in the literature. Most of these usually assume that the effect of maintenance interventions is as good as new. This amounts to assuming the maintenance action undergone by a system, be it preventive or corrective, is equivalent to its replacement. This hypothesis is, of course, questionable in many cases. Maintenance without replacement can lead to a significant level of rejuvenation of a system, either preventively or after repair. However, the restoration of the performances of the system is most of the time incomplete. The effect of such an imperfect maintenance has been described in different ways, which can be split in two main categories: reduction of the value of a degradation variable embodying the ‘health’ of the system, or modification of the lifetime distribution of the system.

This paper focuses on the latter approach, and is structured in two parts. First, it reviews different approaches of imperfect maintenance, modelling the gain in residual lifetime either by a decrease of the failure rate value or by a reduction of the system effective age. Second, an innovative model based on the concepts of elasticity and inescapability of aging is described, in order to introduce more intuitive observations on the results of repeated maintenance actions on a system. This new approach is illustrated using a numerical example.
Piecewise deterministic Markov processes and maintenance modeling: application to maintenance of a train air-conditioning system
Authors: Lair W , Mercier S , Roussignol M , Ziani R
Published: July 2011

This paper deals with the preventive maintenance (PM) optimization of air-conditioning systems used aboard regional trains in France by the SNCF (French Railway Company). Two kinds of PM policies are envisioned: one with a single overhaul in the whole lifetime of the air-conditioning system, another with opportunistic replacements of components that are too old at each system failure. The air-conditioning system is formed of about 20 ageing and stochastically independent components. The envisioned PM policies make them functionally dependent, however. Both PM optimizations are performed with respect to the same cost function, involving the mean number of component replacements on some finite horizon. In view of its numerical assessment, a piecewise deterministic Markov processes (PDMP) model is used, both to model the maintained and the unmaintained system; a deterministic numerical scheme is next proposed, based on finite volume (FV) methods for PDMPs; owing to difficulties in its implementation, an approximation of this scheme is next used, which is much easier to implement than the initial FV scheme. As a result of using this method, it was finally possible to optimize both PM policies, which are both proved to lower the cost function of about 7 per cent.
Optimal periodic condition inspection and replacement policy for a binary monotone system using a counting process approach
Authors: Flage R , Aven T
Published: July 2011

This paper considers a binary monotone system consisting of n components. The system failure process is given by a counting process whose intensity at all times is adapted to information about the system state and at periodic inspection times it is adapted also to information about the component states and their underlying conditions. A parametric policy is introduced prescribing replacement of the entire system either when it enters the failed state, which is observed immediately, or when upon an inspection the intensity is found to have reached a predefined threshold. Costs are associated with inspections, replacements, and system failures, and the periodic inspection interval and intensity threshold that jointly minimize the expected long run cost per unit of time are determined. A numerical example is also included.
Tube Dependence
Authors: Dunitz-Scheer Marguerite , Marinschek Sabine , Beckenbach Hannes , Kratky Elisabeth , Hauer Almuthe , Scheer Peter
Published: July 2011

This article focuses on the issue of tube dependence (TD) in infancy and early childhood. The condition occurs in patients after temporary tube feeding and must be considered as an unintended side effect of modern treatment practices affecting young patients reactively. Whereas some recent literature has described small samples of enterally fed children being exposed to certain weaning programs, the particular phenomenon of unintentional dependence has not been discussed. A tube-dependent child remains tube fed although his/her medical condition and developmental potential would allow the transition to oral nutrition. Children with TD show characteristic symptoms such as food refusal and opposition to any oral feeding attempts. They often suffer from additional episodes of vomiting, nausea, gagging, and retching and in some cases develop severe failure to thrive. Parents of affected children get involved as codependents engaged in constant preparations of the next tube feeds. In this situation, families can become obsessed about wanting their child to learn to eat by himself/herself, ending up in intrusive feeding patterns. Professionals tend to make parents responsible for the behavioral aspects of the condition, but the diagnostic shift of TD into a behavioral category will not help solve the problem. The development of TD can be prevented if typical symptoms are recognized early and effective tube weaning is implemented. Because therapeutic programs exist, the fate of remaining tube dependence should be prevented. This article presents a first overview of a large sample of tube-dependent infants who had been referred specifically for the exclusive sake of tube weaning.
Senate Bill 311
Authors: Shaer Dan , San Mateo Katherine
Published: July 2011

Inborn errors of metabolism (IEMs) are heritable disorders in the biochemical processes of metabolism that occur in approximately 1 in every 1500 live births. The lifelong disorder is treatable through the use of medical foods, specially formulated foods that contain the nutritional content, and dietary restrictions customized to each type of disorder. Without treatment, the buildup of toxic substances in the blood would lead to progressive brain damage, mental retardation, and death. There are approximately 700 different types of IEMs, but today, only 30 are detectable through newborn screening. Each state has mandates to screen for such disorders at birth; however, there are no federal mandates to provide treatment for IEMs. Some states require health insurance companies to cover the costs of these expensive medical foods as treatment, but coverage is insufficient and often expires at adolescence. Senate Bill 311 (S.311), the Medical Foods Equity Act of 2011, proposes to provide coverage of medically necessary foods and other treatment costs under federal health programs and private health insurance. This bill would create uniform access to treatment for all individuals diagnosed with an IEM and reduce the financial burden on families. S.311 would also create a cost–benefit effect in which continuous treatment of IEMs would diminish the risks of developing mental retardation, a disorder that costs significantly more to treat through federal and private health care.
Centralized Model of Human Milk Preparation and Storage in a State-of-the-Art Human Milk Lab
Authors: Gabrielski Lisbeth , Lessen Rachelle
Published: July 2011

Strategies to ensure safe handling and administration of human milk for sick, hospitalized infants are necessary to avoid compromising the integrity of the milk and to prevent administration to the wrong patient. A centralized system of storing and preparing human milk in a milk lab that incorporates multiple verification points using a bar-coding system ensures that the right milk is prepared, delivered, and administered to the right patient, at the right time, and with the right additives. A team of skilled technicians dedicated to handling and preparing human milk, and a system of careful temperature control of refrigerators, freezers, water baths, and warmers, ensures the safety and quality of the milk. Nurses spend less time away from the bedside and more time in patient care when the milk is stored and prepared in a milk lab and delivered ready-to-feed to the bedside. Patient and staff satisfaction are high when a centralized system of storing and preparing human milk is implemented in the hospital setting.
Effects of genetic variations in the Adiponectin pathway genes on the risk of colorectal cancer in the Chinese population
Authors: He Bangshun , Pan Yuqin , Zhang Ying , Bao Qian , Chen Liping , Nie Zhenlin , Gu Ling , Xu Yeqiong , Wang Shukui
Published: July 2011

Background

Decreased expression of adiponectin (ADIPOQ) is associated with an increased risk for developing colorectal cancer (CRC) in humans. This study was designed to determine whether polymorphisms present in theADIPOQand its type 1 receptor (ADIPOR1) could affect the risk of CRC.

Methods

We measured five polymorphisms in theADIPOQand two polymorphisms inADIPOR1, and analyzed their associations with CRC risk in 420 CRC patients and 555 age- and gender-matched healthy individuals.

Results

Multivariate logistic regression analyses revealed that the CRC risks (adjusted odds ratio and 95% confidence interval) associated with theADIPOR1genotypes were 0.53 (95% CI, 0.35-0.81) for rs12733285C/T, 0.59 (95% CI, 0.45-0.78) for rs1342387A/G, and 0.59 (95% CI, 0.39-0.89) for rs1342387A/A, respectively. Furthermore, the risks were more significant in carriers of the allele A of rs1342387A/G (adjusted OR, 0.59; 95% CI, 0.46-0.77) than noncarriers (G/G). In a further subgroup analysis, we observed that rs266729G/C was associated with an increased risk for colon cancer (adjusted OR, 1.50; 95% CI, 1.05-2.14) but not for rectal cancer (adjusted OR, 0.88; 95% CI, 0.63-1.22), and that carriers of the G allele had an increased risk for developing colon cancer (adjusted OR, 1.45; 95% CI, 1.03-2.05).

Conclusions

We conclude that the rs12733285C/T genotype and the carriage of the A allele of rs1342387 (A/G or A/A) inADIPOR1are the protective factors for CRC, while that rs266729G/C and G allele ofADIPOQare the risk factors for colon cancer after excluding rectal cancer cases.
Distinct distribution and prognostic significance of molecular subtypes of breast cancer in Chinese women: a population-based cohort study
Authors: Su Yinghao , Zheng Ying , Zheng Wei , Gu Kai , Chen Zhi , Li Guoliang , Cai Qiuyin , Lu Wei , Shu Xiao Ou
Published: July 2011

Background

Molecular classification of breast cancer is an important prognostic factor. The distribution of molecular subtypes of breast cancer and their prognostic value has not been well documented in Asians.

Methods

A total of 2,791 breast cancer patients recruited for a population-based cohort study were evaluated for molecular subtypes of breast cancer by immunohistochemical assays. Data on clinicopathological characteristics were confirmed by centralized pathology review. The average follow-up of the patients was 53.4 months. Overall and disease-free survival by molecular subtypes of breast cancer were evaluated.

Results

The prevalence of the luminal A, luminal B, human epidermal growth factor receptor 2 (HER2), and triple-negative subtypes were 48.6%, 16.7%, 13.7%, and 12.9%, respectively. The luminal A subtype was more likely to be diagnosed in older women (P = 0.03) and had a stronger correlation with favorable clinicopathological factors (smaller tumor size, lower histologic grade, and earlier TNM stage) than the triple-negative or HER2 subtypes. Women with triple-negative breast cancer had a higher frequency of family history of breast cancer than women with other subtypes (P = 0.048). The 5-year overall/disease-free survival percentages for the luminal A, luminal B, HER2, and triple-negative subtypes were 92.9%/88.6%, 88.6%/85.1%, 83.2%/79.1%, and 80.7%/76.0%, respectively. A similar pattern was observed in multivariate analyses. Immunotherapy was associated with improved overall and disease-free survival for luminal A breast cancer, but reduced disease-free survival (HR = 2.21, 95% CI, 1.09-4.48) for the HER2 subtype of breast cancer.

Conclusions

The triple-negative and HER2 subtypes were associated with poorer outcomes compared with the luminal A subtype among these Chinese women. The HER2 subtype was more prevalent in this Chinese population compared with Western populations, suggesting the importance of standardized HER2 detection and anti-HER2 therapy to potentially benefit a high proportion of breast cancer patients in China.
The economic burden of musculoskeletal disease in Korea: A cross sectional study
Authors: Oh In-Hwan , Yoon Seok-Jun , Seo Hye-Young , Kim Eun-Jung , Kim Young Ae
Published: July 2011

Background

Musculoskeletal diseases are becoming increasingly important due to population aging. However, studies on the economic burden of musculoskeletal disease in Korea are scarce. Therefore, we conducted a population-based study to measure the economic burden of musculoskeletal disease in Korea using nationally representative data.

Methods

This study used a variety of data sources such as national health insurance statistics, the Korea Health Panel study and cause of death reports generated by the Korea National Statistical Office to estimate the economic burden of musculoskeletal disease. The total cost of musculoskeletal disease was estimated as the sum of direct medical care costs, direct non-medical care costs, and indirect costs. Direct medical care costs are composed of the costs paid by the insurer and patients, over the counter drugs costs, and other costs such as medical equipment costs. Direct non-medical costs are composed of transportation and caregiver costs. Indirect costs are the sum of the costs associated with premature death and the costs due to productivity loss. Age, sex, and disease specific costs were estimated.

Results

Among the musculoskeletal diseases, the highest costs are associated with other dorsopathies, followed by disc disorder and arthrosis. The direct medical and direct non-medical costs of all musculoskeletal diseases were $4.18 billion and $338 million in 2008, respectively. Among the indirect costs, those due to productivity loss were $2.28 billion and costs due to premature death were $79 million. The proportions of the total costs incurred by male and female patients were 33.8% and 66.2%, respectively, and the cost due to the female adult aged 20-64 years old was highest. The total economic cost of musculoskeletal disease was $6.89 billion, which represents 0.7% of the Korean gross domestic product.

Conclusions

The economic burden of musculoskeletal disease in Korea is substantial. As the Korean population continues to age, the economic burden of musculoskeletal disease will continue to increase. Policy measures aimed at controlling the cost of musculoskeletal disease are therefore required.
Classification, diagnosis and potential mechanisms in Pontocerebellar Hypoplasia
Authors: Namavar Yasmin , Barth Peter G , Poll-The Bwee Tien , Baas Frank
Published: July 2011

Pontocerebellar Hypoplasia (PCH) is group of very rare, inherited progressive neurodegenerative disorders with prenatal onset. Up to now seven different subtypes have been reported (PCH1-7). The incidence of each subtype is unknown. All subtypes share common characteristics, including hypoplasia/atrophy of cerebellum and pons, progressive microcephaly, and variable cerebral involvement. Patients have severe cognitive and motor handicaps and seizures are often reported. Treatment is only symptomatic and prognosis is poor, as most patients die during infancy or childhood. The genetic basis of different subtypes has been elucidated, which makes prenatal testing possible in families with mutations. Mutations in three tRNA splicing endonuclease subunit genes were found to be responsible for PCH2, PCH4 and PCH5. Mutations in the nuclear encoded mitochondrial arginyl- tRNA synthetase gene underlie PCH6. The tRNA splicing endonuclease, the mitochondrial arginyl- tRNA synthetase and the vaccinia related kinase1 are mutated in the minority of PCH1 cases. These genes are involved in essential processes in protein synthesis in general and tRNA processing in particular. In this review we describe the neuroradiological, neuropathological, clinical and genetic features of the different PCH subtypes and we report on in vitro and in vivo studies on the tRNA splicing endonuclease and mitochondrial arginyl-tRNA synthetase and discuss their relation to pontocerebellar hypoplasia.
DNA sequence characterisation and phylogeography of Lymnaea cousini and related species, vectors of fascioliasis in northern Andean countries, with description of L. meridensis n. sp. (Gastropoda: Lymnaeidae)
Authors: Bargues M Dolores , Artigas Patricio , Khoubbane Messaoud , Mas-Coma Santiago
Published: July 2011

Background

Livestock fascioliasis is a problem throughout Ecuador, Colombia and Venezuela, mainly in Andean areas where the disease also appears to affect humans. Transmission patterns and epidemiological scenarios of liver fluke infection have shown to differ according to the lymnaeid vector snail species involved. These Andean countries present the vectors Lymnaea cousini, L. bogotensis and L. ubaquensis, unknown in the rest of Latin America. An exhaustive combined haplotype study of these species is performed by means of DNA sequencing of the nuclear ribosomal 18S RNA gene, ITS-2 and ITS-1, and mitochondrial DNA cox 1 gene.

Results

The conserved 5.8S rDNA sequence corroborated that no pseudogenes are involved in the numerous non-microsatellite/minisatellite-related indels appearing between the ITS-2 and ITS-1 sequences when comparing different L. cousini - L. bogotensis populations. Sequence analyses and phylogenetic reconstruction methods including other lymnaeid vector species show that (i) L. bogotensis is a synonym of L. cousini, (ii) L. ubaquensis is a synonym of Pseudosuccinea columella, and (iii) populations of L. cousini hitherto known from Venezuelan highlands indeed belong to a new species for which the name L. meridensis n. sp. is proposed. This new species is described and a complete phenotypic differentiation provided.

Conclusions

ITS-2, ITS-1 and cox 1 prove to be good markers for specimen classification and haplotype characterisation of these morphologically similar lymnaeids in endemic areas. Analysis of the 18S gene and phylogenetic reconstructions indicate that L. cousini and L. meridensis n. sp. cluster in an evolutionary line different from the one of P. columella, despite their external resemblance. This suggests an evolutionary phenotypic convergence related to similar environments and which has given rise to frequent specimen misclassification. Body size and phylogenetic relationships of L. meridensis n. sp. with well-known vectors as Lymnaea cousini and P. columella, as well as with Galba/Fossaria species, suggest that the new species may participate in disease transmission to both animals and humans in altitude areas during the yearly window in which temperatures are higher than the F. hepatica minimum development threshold. The involvement of L. cousini and P. columella in the transmission and geographical/altitudinal distribution of fascioliasis in these Andean countries is analysed.
Cumulated Ca2+ spike duration underlies Ca2+ oscillation frequency-regulated NFκB transcriptional activity
Authors: Zhu Liping , Song Shanshan , Pi Yubo , Yu Yang , She Weibin , Ye Hong , Su Yuan , Hu Qinghua
Published: July 2011

[Ca2+]i oscillations drive downstream events, like transcription, in a frequency-dependent manner. Why [Ca2+]i oscillation frequency regulates transcription has not been clearly revealed. A variation in [Ca2+]i oscillation frequency apparently leads to a variation in the time duration of cumulated [Ca2+]i elevations or cumulated [Ca2+]i spike duration. By manipulating [Ca2+]i spike duration, we generated a series of [Ca2+]i oscillations with the same frequency but different cumulated [Ca2+]i spike durations, as well as [Ca2+]i oscillations with the different frequencies but the same cumulated [Ca2+]i spike duration. Molecular assays demonstrated that, when generated in ‘artificial’ models alone, under physiologically simulated conditions or repetitive pulses of agonist exposure, [Ca2+]i oscillation regulates NFκB transcriptional activity, phosphorylation of IκBα and Ca2+-dependent gene expression all in a way actually dependent on cumulated [Ca2+]i spike duration whether or not frequency varies. This study underlines that [Ca2+]i oscillation frequency regulates NFκB transcriptional activity through cumulated [Ca2+]i spike-duration-mediated IκBα phosphorylation.
In vivostrains in the femur of the Virginia opossum (Didelphis virginiana) during terrestrial locomotion: testing hypotheses of evolutionary shifts in mammalian bone loading and design
Authors: Butcher Michael T. , White Bartholomew J. , Hudzik Nathan B. , Gosnell W. Casey , Parrish John H. A. , Blob Richard W.
Published: July 2011

Terrestrial locomotion can impose substantial loads on vertebrate limbs. Previous studies have shown that limb bones from cursorial species of eutherian mammals experience high bending loads with minimal torsion, whereas the limb bones of non-avian reptiles (and amphibians) exhibit considerable torsion in addition to bending. It has been hypothesized that these differences in loading regime are related to the difference in limb posture between upright mammals and sprawling reptiles, and that the loading patterns observed in non-avian reptiles may be ancestral for tetrapod vertebrates. To evaluate whether non-cursorial mammals show loading patterns more similar to those of sprawling lineages, we measured in vivo strains in the femur during terrestrial locomotion of the Virginia opossum (Didelphis virginiana), a marsupial that uses more crouched limb posture than most mammals from which bone strains have been recorded, and which belongs to a clade phylogenetically between reptiles and the eutherian mammals studied previously. The presence of substantial torsion in the femur of opossums, similar to non-avian reptiles, would suggest that this loading regime likely reflects an ancestral condition for tetrapod limb bone design. Strain recordings indicate the presence of both bending and appreciable torsion (shear strain: 419.1±212.8 με) in the opossum femur, with planar strain analyses showing neutral axis orientations that placed the lateral aspect of the femur in tension at the time of peak strains. Such mediolateral bending was unexpected for a mammal running with near-parasagittal limb kinematics. Shear strains were similar in magnitude to peak compressive axial strains, with opossum femora experiencing similar bending loads but higher levels of torsion compared with most previously studied mammals. Analyses of peak femoral strains led to estimated safety factor ranges of 5.1–7.2 in bending and 5.5–7.3 in torsion, somewhat higher than typical mammalian values for bending, but approaching typical reptilian values for shear. Loading patterns of opossum limb bones therefore appear intermediate in some respects between those of eutherian mammals and non-avian reptiles, providing further support for hypotheses that high torsion and elevated limb bone safety factors may represent persistent ancestral conditions in the evolution of tetrapod limb bone loading and design.
Associative olfactory learning in the desert locust, Schistocerca gregaria
Authors: Simões Patrício , Ott Swidbert R. , Niven Jeremy E.
Published: July 2011

Locusts can learn associations between olfactory stimuli and food rewards, and use the acquired memories to choose between foods according to their nutrient requirements. They are a model system for both the study of olfactory coding and insect nutritional regulation. Previous studies have used operant paradigms for conditioning freely moving locusts, restricting the study of the neural mechanisms underlying the acquisition of olfactory memories, which requires restrained preparations for electrophysiological recordings. Here we present two complementary paradigms for the classical conditioning of olfactory memories in restrained desert locusts (Schistocerca gregaria). These paradigms allow precise experimental control over the parameters influencing learning. The first paradigm is based on classical (Pavlovian) appetitive conditioning. We show that opening of the maxillary palps can be used as a measure of memory acquisition. Maxillary palp opening in response to odour presentation is significantly higher in locusts trained with paired presentation of an odour and a food reward than in locusts trained either with unpaired presentation of food and odour or the odour alone. The memory formed by this conditioning paradigm lasts for at least 24 h. In the second paradigm, we show that classical conditioning of an odour memory in restrained locusts influences their decisions in a subsequent operant task. When locusts that have been trained to associate an odour with a food reward are placed in a Y-maze, they choose the arm containing that odour significantly more often than naïve locusts. A single conditioning trial is sufficient to induce a significant bias for that odour for up to 4 h. Multiple- and block-trial training induce a significant bias that lasts at least 24 h. Thus, locusts are capable of forming appetitive olfactory memories in classical conditioning paradigms and can use these memories to modify their decisions.
Evidence that potential fish predators elicit the production of carapace vibrations by the American lobster
Authors: Ward Daniel , Morison Françoise , Morrissey Elizabeth , Jenks Kyle , Watson Winsor H.
Published: July 2011

American lobsters (Homarus americanus) will on rare occasions produce sounds by vibrating their dorsal carapace. Although this behavior can be elicited in the laboratory by handling lobsters, the stimulus that triggers the production of sounds in the lobster's natural habitat is not known. We investigated the influence of two fish that are known to prey on lobsters, cod (Gadus morhua) and striped bass (Morone saxatilis), on the production of sounds by American lobsters. In addition, we examined the response of the same fish to the sounds the lobsters produced. Although solitary lobsters spontaneously produced sounds at a low rate of 1.2±0.23 sound events per 30 min, the presence of a single cod or striped bass led to an increase in the rate of sound production (cod: 51.1±13.1 events per 30 min; striped bass: 17.0±7.0 events per 30 min). Most (74.6±6.6%) of the 292 sound events recorded occurred when a fish came within 0.5 m of a lobster, but a fish did not have to come into contact with a lobster to elicit sounds. Immediately following the production of a sound by a lobster, fish turned and swam away significantly faster than when they encountered a lobster that did not make a sound. Moreover, after striped bass (but not cod) experienced a number of these sound events, they subsequently tended to avoid swimming close to the lobsters. These data, taken together, suggest that sound production by American lobsters may serve to deter potential fish predators.
Penguins are attracted to dimethyl sulphide at sea
Authors: Wright Kyran L. B. , Pichegru Lorien , Ryan Peter G.
Published: July 2011

Breeding Spheniscus penguins are central place foragers that feed primarily on schooling pelagic fish. They are visual hunters, but it is unclear how they locate prey patches on a coarse scale. Many petrels and storm petrels (Procellariiformes), the penguins' closest relatives, use olfactory cues to locate prey concentrations at sea, but this has not been demonstrated for penguins. Procellariiforms are attracted to a variety of olfactory cues, including dimethyl sulphide (DMS), an organosulphur compound released when phytoplankton is grazed, as well as fish odorants such as cod liver oil. A recent study found that African penguins Spheniscus demersus react to DMS on land. We confirm this result and show that African penguins are also attracted by DMS at sea. DMS-scented oil slicks attracted 2–3 times more penguins than control slicks, whereas penguins showed no response to slicks containing cod liver oil. The number of penguins attracted to DMS increased for at least 30 min, suggesting penguins could travel up to 2 km to reach scent cues. Repeats of land-based trials confirmed previous results showing DMS sensitivity of penguins on land. Our results also support the hypothesis that African penguins use DMS as an olfactory cue to locate prey patches at sea from a distance, which is particularly important given their slow commuting speed relative to that of flying seabirds.
Fourier Transform–Near Infrared Spectroscopy in-line Monitoring of the Enzymatic Hydrolysis of Starch in Rye: Water Mashes for First-Generation Bioethanol Production
Authors: Tamburini Elena , Bernardi Tatiana , Castaldelli Giuseppe
Published: July 2011

The application described in this paper addresses problems encountered during the large-scale production of ethanol from renewable sources. Bioethanol can be produced from several starchy raw materials (for example, wheat, corn, barley, rye). After hydrolysis to glucose, starch can be converted to ethanol by fermentation. The hydrolysis of starch requires a multi-phase process using different enzymes. The degree of hydrolysis is a critical parameter because it determines the physical and chemical properties of the final products. The aims of this work were to monitor the enzymatic hydrolysis of starch from rye using Fourier-transform near infrared (FT-NIR) spectroscopy and to identify barriers for an industrial-scale application of this technology. The enzymatic hydrolysis of starch from rye was carried out in three steps using commercially available enzymes. AFT-NIR reflectance probe was immersed in the reactor to monitor the different phases of the hydrolysis process. The most significant parameters submitted to the NIR calibration were the percentage of dry matter (%w/v) (as measured by °Brix) and the concentrations of maltotriose, maltose and glucose (% w/v). Partial least squares calibration models were built using 24 samples and spectra for measuring °Brix, 32 samples for maltotriose and 48 samples for both maltose and glucose, respectively. The models were considered to be promising in terms of the squared Pearson correlation coefficient (0.89 < R2< 0.99) and standard error of estimation (0.12 < SEE<0.60) and were successfully used in situ to automatically monitor the entire process (0.17< SEP<0.45).
Classification of Viable and Non-Viable Spinach (Spinacia Oleracea L.) Seeds by Single Seed near Infrared Spectroscopy and Extended Canonical Variates Analysis
Authors: Olesen Merete Halkjaer , Shetty Nisha , Gislum Rene , Boelt Birte
Published: July 2011

Near-infrared (NIR) reflectance spectroscopy is a common non-destructive method for predicting seed quality parameters, such as moisture, oil, carbohydrates and protein content. Furthermore, variations in absorbance between germinating and non-germinating seeds have been shown in single seed studies. Spinach ( Spinacia oleracea L.) is the major crop in vegetable seed production in Denmark and two seed lots with viability percentages of 90% and 97% were chosen for examination by single seed NIR spectroscopy. Lipids play a major role in both ageing and germination. During accelerated ageing, lipid peroxidation leads to deterioration of cell membranes and contributes in that way to reducing seed viability of the seed sample. These biochemical changes may be the reason for a clear grouping between aged and non-aged seeds when performing the extended canonical variates analysis (ECVA). Assigning the difference of scatter corrected absorbance spectra from aged and non-aged seeds also lead to CH2, CH3 and HC=CH structures, which are some of the functional groups in lipids. In the ECVA plot, there was a clear difference between seeds with and without a pericarp. Evaluating the spectra, the pattern of peaks was almost similar, but the intensity was different in the absorption band at 1350 nm. The number of misclassified seeds ranged from 1.7% to 10.5% and it was lowest in seeds with a pericarp. This indicates the influence of the pericarp during germination, which is in accordance with earlier studies of spinach seeds. Single seed NIR and ECVA classification are potential methods for the prediction of seed viability.
Downregulation of Clock in circulatory system leads to an enhancement of fibrinolysis in mice
Authors: Cheng Shuting , Jiang Zhou , Zou Yan , Chen Chen , Wang Yuhui , Liu Yanyou , Xiao Jing , Guo Huiling , Wang Zhengrong
Published: July 2011

As a main component of circadian genes, clock plays not only an important role in circadian rhythm but also in the regulation of many physiological systems. The dysfunction of clock genes is associated with the development of various disorders. Many studies have investigated the association between clock genes and blood coagulation and the fibrinolytic system. The present study was designed to investigate the effect of downregulation of circulatory Clock on blood coagulation and fibrinolysis at the initial stage of active phase in male mice. Downregulation of the expression of the Clock gene by siRNA and, subsequently, its effect on the thrombotic potential and the expression of relative coagulative and/or fibrinolytic factors were investigated. It was found that the Clock interfered mice were less liable to thrombosis and showed prolonged prothrombin time (PT) and activated partial thromboplastin time (APTT) at Zeitgeber time (ZT) 15. Meanwhile, these mice also showed an increase in factor VII (FVII) and a decrease in thrombomodulin (TM) and plasminogen activator inhibitor 1 (PAI-1) at ZT 15 at both transcriptional and translational levels. PT, APTT and mRNA expressions of fvii, tm and pai-1 were analyzed with the least-squares fit of a 24-h cosine function by single cosinor method; no circadian rhythm was determined in PT and APTT, and a higher amplitude of fvii in the Clock RNAi group was found with a circadian phase shift, while lower amplitudes of tm and pai-1 were found in the Clock RNAi group with nearly no phase shift. All these results suggest that downregulation of the Clock gene in circulatory system has an effect on factors involved in both blood coagulation and fibrinolysis resulting in an enhancement in mice. This may be considered as an indication that Clock regulates thrombotic homeostasis through the fibrinolytic system.
Use of the NHS Choices website for primary care consultations: results from online and general practice surveys
Authors: Murray Joanna , Majeed Azeem , Khan Muhammad Saleem , Lee John Tayu , Nelson Paul
Published: July 2011

Objectives

To determine the effect of using the NHS Choices website on primary care consultations in England and Wales. We examined the hypothesis that using NHS Choices may reduce the frequency of primary care consultations among young, healthy users.

Design

Two cross-sectional surveys of NHS Choices users.

Setting

Survey of NHS Choices users using an online pop-up questionnaire on the NHS Choices website and a snapshot survey of patients in six general practices in London.

Participants

NHS Choices website users and general practice patients.

Main outcome measures

For both surveys, we measured the proportion of people using NHS Choices when considering whether to consult their GP practice and on subsequent frequency of primary care consultations.

Results

Around 59% ( n = 1559) of online and 8% ( n = 125) of general practice survey respondents reported using NHS Choices in relation to their use of primary care services. Among these, 33% ( n = 515) of online and 18% ( n = 23) of general practice respondents reported reduced primary care consultations as a result of using NHS Choices. We estimated the equivalent capacity savings in primary care from reduced consultations as a result of using NHS Choices to be approximately £94 million per year.

Conclusions

NHS Choices has been shown to alter healthcare-seeking behaviour, attitudes and knowledge among its users. Using NHS Choices results in reduced demand for primary care consultations among young, healthy users for whom reduced health service use is likely to be appropriate. Reducing potentially avoidable consultations can result in considerable capacity savings in UK primary care.
Adaptive Data-Driven Inventory Control with Censored Demand Based on Kaplan-Meier Estimator
Authors: Huh Woonghee Tim , Levi Retsef , Rusmevichientong Paat , Orlin James B.
Published: July 2011

Using the well-known product-limit form of the Kaplan-Meier estimator from statistics, we propose a new class of nonparametric adaptive data-driven policies for stochastic inventory control problems. We focus on the distribution-free newsvendor model with censored demands. The assumption is that the demand distribution is not known and there are only sales data available. We study the theoretical performance of the new policies and show that for discrete demand distributions they converge almost surely to the set of optimal solutions. Computational experiments suggest that the new policies converge for general demand distributions, not necessarily discrete, and demonstrate that they are significantly more robust than previously known policies. As a by-product of the theoretical analysis, we obtain new results on the asymptotic consistency of the Kaplan-Meier estimator for discrete random variables that extend existing work in statistics. To the best of our knowledge, this is the first application of the Kaplan-Meier estimator within an adaptive optimization algorithm, in particular, the first application to stochastic inventory control models. We believe that this work will lead to additional applications in other domains.
Strategic Behavior and Social Optimization in Markovian Vacation Queues
Authors: Guo Pengfei , Hassin Refael
Published: July 2011

We consider a single server queueing system in which service shuts down when there are no customers present and is resumed only when the queue length reaches a given critical length. We analyze the strategic response of customers to this mechanism and compare it to the overall optimal behavior, with and without information on delay. The results are significantly different from those obtained when the server is continuously available. We show that there may exist multiple equilibria in such a system and the optimal arrival rate may be greater or smaller than that of the decentralized equilibrium. Finally, the critical length is taken as a decision variable, and the optimal operations policy is discussed by taking strategic customers into consideration.
Managing a Noncooperative Supply Chain with Limited Capacity
Authors: Parker Rodney P. , Kapuściński Roman
Published: July 2011

We consider a two-stage serial supply chain with capacity limits, where each installation is operated by managers attempting to minimize their own costs. A multiple-period model is necessitated by the multiple stages, capacity limits, stochastic demand, and the explicit consideration of inventories. With appropriate salvage value functions, a Markov equilibrium policy is found. Intuitive profit dominance allows for existence of a unique equilibrium solution, which is shown to be a modified echelon base-stock policy. This equilibrium policy structure is sustained in the infinite horizon. A numerical study compares the behavior of the decentralized system with the first-best integrated capacitated system. The performance of this decentralized system relative to the integrated system across other parameters can be very good over a broad range of values. This implies that an acceptable system performance may be attained without the imposition of a contract or other coordinating mechanism, which themselves may encounter difficulties in implementation in the form of negotiation, execution, or enforcement of these agreements. We find instances where tighter capacities may actually enhance channel efficiency. We also examine the effect of capacity utilization on the system suboptimality.
Environmental Impact Assessment: Mapping the Interface between Agriculture, Development and the Natural Environment?
Authors: Rodgers Christopher
Published: July 2011

Maintaining a balance between promoting agriculture and food production, and controlling or minimising its environmental impacts, has always been problematic. Since 1947, changes in agricultural land use have largely remained outside the scope of the planning system, whatever their negative environmental implications. The assumption that agricultural development should remain beyond legal scrutiny has been challenged in recent years by initiatives originating in European environmental law, and in particular by the implementation of the 1985 Directive on Environmental Impact Assessment. The Directive requires an EIA of proposals to convert semi-natural areas to intensive agricultural production, and of projects for restructuring rural land holdings. These are categories of land use change which have, since 1947, been assumed to be outside the remit of development control. Nevertheless, the English courts have recently shown a willingness to extend its reach into areas of agricultural land use that were hitherto assumed to be outside the planning system altogether. This article reviews several recent cases – notably R (Hall Hunter Partnership) v Secretary of State (2006) and R (on the application of Wye Valley Action Association Ltd) v Herefordshire District Council (2011) – in which proposals to adopt intensive agricultural land uses have been challenged in the courts. It reviews the application of EIA to agricultural development – both within the planning system and under separate regulations adopted for non-planning cases. It considers the scope for “horizontal” environmental mechanisms such as EIA to address environmental protection issues at the interface between agriculture, “development” and the natural environment.
Septins as key regulators of actin based processes in bacterial infection
Authors: Mostowy Serge , Cossart Pascale
Published: July 2011

Many pathogens have evolved a variety of mechanisms to exploit the host-cell actin cytoskeleton during infection, either to enter into cells or to move within cells. These events have been investigated and documented in detail. Yet, a complete picture of the molecules and mechanisms regulating entry and intracellular movement remains to be established. Here we present a series of studies revealing that in addition to actin rearrangements the host cell also employs septins, a relatively newly characterized component of the cell cyto-skeleton, to regulate bacterial entry and restrict the dissemination of cytosolic bacteria. The challenge now is to decipher the precise role of septins during actin rearrangements and how these different cytoskeleton components orchestrate infection processes.
Horizontal Transmission Rapidly Erodes Disequilibria Between Organelle and Symbiont Genomes
Authors: Brandvain Yaniv , Goodnight Charles , Wade Michael J
Published: July 2011

We investigate the generation and decay of interspecific disequilibrium (ID) between organelle and symbiont genomes as a function of the rate of horizontal transmission. We show that rare horizontal transmission greatly diminishes the covariance between organelle and symbiont genomes. This result has two important implications. First, a low level of ID does not indicate low levels of vertical transmission. Second, even with low levels of horizontal transmission, the additive effects of host and symbiont loci will determine the response to selection, while epistatic effects will not be selectable.
Remineralization of Artificial Dentin Lesions via the Polymer-Induced Liquid-Precursor (PILP) Process
Authors: Thula-Mata Taili , Burwell Anora , Gower Laurie B. , Habelizt Stefan , Marshall Grayson
Published: July 2011

Acid-etched dentin samples with a zone of demineralized dentin were remineralized via the polymer-induced liquid-precursor (PILP) process. Poly-L-aspartic acid was used as the polymeric process-directing agent. Samples were incubated in the mineralization solution for 1- 4 weeks. Dentin samples remineralized by the PILP process presented a surface morphology very similar to the intact mineralized dentin’s architecture, in contrast to samples mineralized via the conventional nucleation and growth method (without polymer additive), which led to a superficial crust of randomly organized mineral crystals. Energy dispersive x-ray spectroscopy analysis of the PILP-mineralized samples showed the presence of calcium and phosphate ions at high levels. Since no hydroxyapatite (HA) clusters were observed on the surface of the PILP-mineralized samples, we could conclude the signal was produced from the mineral embedded within the dentin matrix. TEM and diffraction analyses suggest that both intrafibrillar and interfibrillar remineralization occurred in the demineralized dentin matrix.
Culturally Responsive Social Skills Instruction for Adolescent Black Males
Authors: Robinson-Ervin Porsha , Cartledge Gwendolyn , Keyes Starr
Published: July 2011

The cultural disconnect between black males and the school environment has been correlated with poor academic achievement and high discipline rates for Black males. Instructional strategies that draw upon the learners cultural background hold promise as one means for intervention. This paper addresses the social skills needs of black adolescent males and the relationship between cultural relevance and high rates of discipline and academic disproportionality. Culturally relevant social skills instruction is discussed as a proactive, innovative, and practical method of teaching social skills to black male adolescents. Applied examples incorporating culturally relevant music, media, and books into social skills instruction are provided.
Of Reductionism and The Pendulum Swing: Connecting Toxicology and Human Health
Authors: Hanekamp Jaap C , Bast Aalt , Kwakman Jan HJM
Published: July 2011

In this contribution we will show that research in the field of toxicology, pharmacology and physiology is by and large characterised by a pendulum swing of which the amplitudes represent risks and benefits of exposure. As toxicology usually tests at higher levels than the populace routinely is exposed to, it reverts to mostly linear extrapolative models that express the risks of exposure, irrespective of dosages, only. However, as we will explicate in two examples, depending on dosages, it is less easy to separate risks and benefits than current toxicological research and regulatory efforts suggest. The same chemical compound, in the final analysis, is represented within the boundaries of both amplitudes, that is, show a biphasic, hormetic, dose-response. This is notable, as low-level exposures from the food-matrix are progressively more under scrutiny as a result of increasing analytical capabilities. Presence of low-level concentrations of a chemical in food is a regulatory proxy for human health, but in light of this hormetic dose-response objectionable. Moreover, given that an ecological threshold probably holds for most, if not all, man-made (bio)organic chemicals, these will be found to be naturally present in the food matrix. Both aspects require toxicology to close the gap between reductionist models and its extrapolative deficiencies and real-life scenarios.
Linear Non-Threshold: Separating Facts from Fiction
Authors: Moghissi A. Alan , Love Betty R. , Straja Sorin R.
Published: July 2011

The Linear Non-Threshold (LNT) process is used by virtually all governmental agencies to compute incidence of cancer as a consequence of exposure to a carcinogen. This comment applies the concept of Best Available Science (BAS) Metrics for Evaluation of Scientific Claims (MESC) derived from BAS to issues related to reliability of LNT hypothesis. This paper identifies the level of maturity of the LNT hypothesis and the associated uncertainties.