673 research outputs found

    Mathematical Model of \u3cem\u3eChlorella minutissima\u3c/em\u3e UTEX2341 Growth and Lipid Production Under Photoheterotrophic Fermentation Conditions

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    To reduce the cost of algal biomass production, mathematical model was developed for the first time to describe microalgae growth, lipid production and glycerin consumption under photoheterotrophic conditions based on logistic, Luedeking–Piret and Luedeking–Piret-like equations. All experiments were conducted in a 2 L batch reactor without considering CO2 effect on algae’s growth and lipid production. Biomass and lipid production increased with glycerin as carbon source and were well described by the logistic and Luedeking–Piret equations respectively. Model predictions were in satisfactory agreement with measured data and the mode of lipid production was growth-associated. Sensitivity analysis was applied to examine the effects of certain important parameters on model performance. Results showed that S0, the initial concentration of glycerin, was the most significant factor for algae growth and lipid production. This model is applicable for prediction of other single cell algal species but model testing is recommended before scaling up the fermentation of process

    Reliability modelling of dispensing processes in community pharmacy

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    Studies of error rates in community pharmacies have reported error rates of between 0.014% and 3.3% per item dispensed. This suggests up to 36 million items per year may contain errors in England. In addition, literature shows that patient satisfaction with services is directly related to waiting times. There is a need for a method to model pharmacy efficiency balancing safety and waiting times, ensuring that the reliability of the dispensing process is not compromised. In this paper a Coloured Petri Net (CPN) approach is proposed for analysing reliability and efficiency of community pharmacy. A pharmacy team work to complete dispensing and non-dispensing tasks, where non-dispensing tasks require staff to be temporarily removed from the dispensing process. The proposed approach is useful to investigate what affects the error rates and long waiting times, and provides modelling-based evidence to decision makers, looking to optimise staffing levels and improve the reliability of dispensing

    The sediment of mixtures of charged colloids: segregation and inhomogeneous electric fields

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    We theoretically study sedimentation-diffusion equilibrium of dilute binary, ternary, and polydisperse mixtures of colloidal particles with different buoyant masses and/or charges. We focus on the low-salt regime, where the entropy of the screening ions drives spontaneous charge separation and the formation of an inhomogeneous macroscopic electric field. The resulting electric force lifts the colloids against gravity, yielding highly nonbarometric and even nonmonotonic colloidal density profiles. The most profound effect is the phenomenon of segregation into layers of colloids with equal mass-per-charge, including the possibility that heavy colloidal species float onto lighter ones

    On Markov operators preserving polynomials

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    The paper is concerned with a special class of positive linear operators acting on the space C(K) of all continuous functions defined on a convex compact subset K of R^d, d \geq 1, having non-empty interior. Actually, this class consists of all positive linear operators T on C(K) which leave invariant the polynomials of degree at most 1 and which, in addition, map polynomials into polynomials of the same degree. Among other things, we discuss the existence of such operators in the special case where K is strictly convex by also characterizing them within the class of positive projections. In particular we show that such operators exist if and only if ∂K is an ellipsoid. Furthermore, a characterization of balls of R^d in terms of a special class of them is furnished. Additional results and illustrative examples are presented as well

    Factors Influencing Trends in Opioid Prescribing for Older People: A Scoping Review

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    Aim: The review aimed to identify factors influencing opioid prescribing as regular pain-management medication for older people. Background: Chronic pain occurs in 45–85% of older people but appears to be under-recognised and undertreated. However, strong opiate prescribing is more prevalent in older people, increasing at the fastest rate in this age group. Method: This review included all study types, published 1990-2017, which focused on opioid prescribing for pain-management among older adults. Arksey and O’Malley’s (2005) framework was used to scope the literature. PubMed, EBSCO Host, the UK Drug Database and Google Scholar were searched. Data extraction, carried out by two researchers, included factors explaining opioid prescribing patterns and prescribing trends. Findings: 613 papers were identified and 53 were included in the final review consisting of 35 research papers, 10 opinion pieces and 8 grey literature sources. Factors associated with prescribing patterns were categorised according to whether they were patient-related, prescriber-driven or system driven. Patient factors included age, gender, race and cognition; prescriber factors included attitudes towards opioids and judgements about ‘normal’ pain; and policy/system factors related to the changing policy landscape over the last three decades, particularly in the USA. Conclusion: A large number of context-dependent factors appeared to influence opioid prescribing for chronic pain-management in older adults but the findings were inconsistent. There is a gap in the literature relating to the UK healthcare system; the prescriber and the patient perspective; and within the context of multi-morbidity and treatment burden

    Inflammatory Bowel Diseases (Crohn's Disease and Ulcerative Colitis): Cost of Treatment in Serbia and the Implications

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    BACKGROUND: Although the costs of treating inflammatory bowel disease (IBD) in developed countries are well established, they remain largely unknown in countries with recent histories of socio-economic transition including Serbia. OBJECTIVE: To estimate the costs of treatment including the resources used by patients with IBD in Serbia from a societal perspective. This includes both Crohn's disease and ulcerative colitis. METHODS: This cost-of-illness study was conducted to identify direct, indirect and out-of-pocket costs of treating patients with IBD in Serbia. Patients with IBD (n = 112) completed a semi-structured questionnaire with data concerning their utilisation of heath-care resources and illness-related expenditures. All costs were calculated in Republic of Serbia dinars (RSD) at a 1-year level (2014) and subsequently converted to Euros. Median values and ranges were reported to avoid potential distortions associated with mean costs. RESULTS: Median total direct costs and total indirect costs per patient per year in patients with Crohn's disease were 192,614.32RSD (€1602.97) and 28,014.00RSD (€233.13) and 142,267.15RSD (€1183.97) and 21,436.00RSD (€178.39), respectively, in patients with ulcerative colitis. In both groups, the greatest component of direct costs was hospitalisation. CONCLUSIONS: Costs of IBD in Serbia are lower than in more developed countries for two reasons. These include the fact that expensive biological therapy is currently under-utilised in Serbia and prices of health services are largely controlled by the State at a low level. The under-utilisation of biologicals may change with the advent of biosimilars at increasingly lower prices

    Application of Room Temperature Ionic Liquids to the Development of Electrochemical Lipase Biosensing Systems for Water-Insoluble Analytes

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    Biosensors have been prepared by modification of glassy carbon electrodes with functionalised multiwalled carbon nanotubes (MWCNT) dispersed in the room temperature ionic liquid, 1-butyl-3-methylimidazolium bis(trifluoromethane)sulfonimide (BmimNTF2) and with lipase cross-linked with glutaraldehyde. The biosensor was applied to the determination of olive oil triglycerides by cyclic voltammetry. A phosphate buffer (pH 7.0) / BmimNO3 mixture is a better electrolyte than aqueous buffer alone. The response signal in the buffer-BmimNO3 mixture was found to increase with the number of cycles until a constant current was achieved. The calibration curve obtained exhibited a sigmoid-shape and a fourparameter model was used to fit the data which gave a limit of detection of 0.11 μg mL−1. Close inspection of such calibration curves showed two distinct linear regions indicating changes in the mechanism of the electrochemical response. Overall, the oxidative analytical response was found to be due to phenolic compounds present in the olive oil, released in the presence of lipase, rather than due to triglycerides per se. It was also found that there were no interferences from either cholesterol or glycerol. A possible mechanism of olive oil determination at a MWCNT-BmimNTF2/Lip biosensor is proposed

    Fra restråstoff til verdifulle råvarer

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    Laying hens are commonly not slaughtered and utilized for food purpose. Slaughtered hens may be hydrolyzed (e.g. at 50°C for 1-2 hours, with additions of enzymes)to produce soluble proteins and oils. Sediments after such hydrolysis are valuable fertilizers, whereas the oil and proteins are valuable food ingredients of high quality

    Analisis Faktor Yang Memengaruhi Minat Investasi Gen-Z Terhadap Produk Keuangan Syariah

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    Indonesia dengan populasi muslim terbesar di dunia menjadikan investasi syariah menjadi pilihan yang populer bagi masyarakat Indonesia. Hal tersebut terlihat dari jumlah saham syariah yang tercatat di dalam bursa. Penelitian ini bertujuan untuk mengetahui faktor-faktor apa saja yang lebih berpengaruh terhadap minat investasi mahasiswa ekonomi syariah pada produk keuangan syariah. Artikel ini merupakan penelitian kuantitatif dengan data primer. Data diolah melalui program SPSS dengan menggunakan uji-t. Untuk pengumpulan data, peneliti menyebarkan kuisioner kepada mahasiswa aktif ekonomi syariah Fakultas Ekonomi dan Bisnis Islam. Hasil dari penelitian ini hasil adalah seluruh variabel yang diantaranya variabel pemahaman investasi, return, resiko, dan motivasi secara bersamaan berpengaruh terhadap variabel dependen yaitu minat investasi mahasiswa ekonomi syariah pada produk keuangan syariah. Kata Kunci: Investasi, Keuangan Syariah, Mahasiswa, Minat 
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