A cost-effective method to quantify biological surface sediment reworking

We propose a simple and inexpensive method to determine the rate and pattern of surface sediment reworking by benthic organisms. Unlike many existing methods commonly used in bioturbation studies, which usually require sediment sampling, our approach is fully non-destructive and is well suited for investigating non-cohesive fine sediments in streams and rivers. Optical tracer (e.g., luminophores or coloured sand) disappearance or appearance is assessed through time based on optical quantification of surfaces occupied by tracers. Data are used to calculate surface sediment reworking (SSR) coefficients depicting bioturbation intensities. Using this method, we evaluated reworking activity of stream organisms (three benthic invertebrates and a fish) in laboratory microcosms mimicking pool habitats or directly in the field within arenas set in depositional zones. Our method was sensitive enough to measure SSR as low as 0.2 cm2.d-1, such as triggered by intermediate density (774 m-2) of Gammarus fossarum (Amphipoda) in microcosms. In contrast, complex invertebrate community in the field and a fish (Barbatula barabatula) in laboratory microcosms were found to yield to excessively high SSR (>60 cm2.d-1). Lastly, we suggest that images acquired during experiments can be used for qualitative evaluation of species-specific effects on sediment distribution

A Cost-effective Shuffling Method against DDoS Attacks using Moving Target Defense

Moving Target Defense (MTD) has emerged as a newcomer into the asymmetric field of attack and defense, and shuffling-based MTD has been regarded as one of the most effective ways to mitigate DDoS attacks. However, previous work does not acknowledge that frequent shuffles would significantly intensify the overhead. MTD requires a quantitative measure to compare the cost and effectiveness of available adaptations and explore the best trade-off between them. In this paper, therefore, we propose a new cost-effective shuffling method against DDoS attacks using MTD. By exploiting Multi-Objective Markov Decision Processes to model the interaction between the attacker and the defender, and designing a cost-effective shuffling algorithm, we study the best trade-off between the effectiveness and cost of shuffling in a given shuffling scenario. Finally, simulation and experimentation on an experimental software defined network (SDN) indicate that our approach imposes an acceptable shuffling overload and is effective in mitigating DDoS attacks

Effective branching splitting method under cost contraint

This paper deals with the splitting method first introduced in rare event analysis. In this technique, the sample paths are split into R multiple copies at various stages during the simulation. Given the cost, the optimization of the algorithm suggests to sample a number of subtrials which may be non-integer and even unknown but estimated. In this paper, we present three different approaches to face this problem which provide precise estimates of the relative error between P(A) and its estimator

EFFECTIVE COST ANALYSIS TOOLS OF THE ACTIVITY-BASED COSTING (ABC) METHOD

This article focuses on cost analysis and specific tools of Activity-Based Costing(ABC) method. After presenting the main categories of operating costs of ABC method it isswitching to presenting the most important tools for monitoring and measuring performance, suchas the dashboard, balanced scorecard, benchmarking etc. Components and benefits and thepresentation of these situations are highlighted. The article ends with the conclusions of authorsabout analysis of these instruments also the advantages of them, the authors advocating the use ofthese types, since they represent advanced cases of analysis of performance derived from an assetthat unit would be successfully applied in Romania.dashboard, balanced scorecard, benchmarking, Activity-Based Costing, performance.

A Cost-Effective Method of Skills Practice

Practice equipment costs for students have soared in the last ten to fifteen years. The dilemma is how to achieve the required level of skill proficiency in a cost-efficient manner. Due to the high cost of disposable equipment and supplies, our university could not afford to provide each student with a sterile unopened kit. We searched for a way for students to have the experience of opening a kit and using it for the first time in a simulated learning environment. Our teaching team in the Adult Nursing course decided to let the students purchase a large packet of materials to be used throughout the course

Intradermal antirabies vaccination: a cost-effective method

Background: Compliance to post-exposure vaccination is crucial to achieve optimum level of antibody titers. The present study was planned to assess the cost effectiveness of 4 dose intradermal regimen over 5 dose intramuscular regimen. The objective of present study is to reveal cost effectiveness of intradermal regimen over intramuscular PEP regimenMethods: Hospital record based study. Patients who attended antirabies clinic from Jan 2010 to Dec 2010 were studied. 2051 patients who were given Inj. PCECV by intradermal route formed the study group. Pearson’s Chi square test was used as a test of significance.Results: 2051 patients were studied.1741 (84.9%) patients were male.1907 (92.9%) were dog bites. 1277(62.3%) were stray dog bites. 1516 (58.0%) were class III dog bites.1313 (68.2%) were non-observable dog bites.1711 (88.7%) were provoked dog bites. Most common site of dog bite was over the lower limb i.e.1350 (70.2%).1255 (65.3%) patients completed the 4 dose regimen. This is in stark contrast to previous evidence from our centre in which a compliance of 40.2% to the intramuscular regimen was evident. (Pearson X2 = 180.94, df= 1, p< 0.0001). Cost effectiveness favored intradermal regimen over intramuscular regimen.Conclusions: It was observed intradermal regimen had more cost effectiveness compared to intramuscular regimen

A novel cost effective and high-throughput isolation and identification method for marine microalgae

Background: Marine microalgae are of major ecologic and emerging economic importance. Biotechnological screening schemes of microalgae for specific traits and laboratory experiments to advance our knowledge on algal biology and evolution strongly benefit from culture collections reflecting a maximum of the natural inter- and intraspecific diversity. However, standard procedures for strain isolation and identification, namely DNA extraction, purification, amplification, sequencing and taxonomic identification still include considerable constraints increasing the time required to establish new cultures. Results: In this study, we report a cost effective and high-throughput isolation and identification method for marine microalgae. The throughput was increased by applying strain isolation on plates and taxonomic identification by direct PCR (dPCR) of phylogenetic marker genes in combination with a novel sequencing electropherogram based screening method to assess the taxonomic diversity and identity of the isolated cultures. For validation of the effectiveness of this approach, we isolated and identified a range of unialgal cultures from natural phytoplankton communities sampled in the Arctic Ocean. These cultures include the isolate of a novel marine Chlorophyceae strain among several different diatoms. Conclusions: We provide an efficient and effective approach leading from natural phytoplankton communities to isolated and taxonomically identified algal strains in only a few weeks. Validated with sensitive Arctic phytoplankton, this approach overcomes the constraints of standard molecular characterisation and establishment of unialgal cultures

a fast and cost-effective reverse engineering method

Tese de mestrado, Engenharia Farmacêutica, 2022, Universidade de Lisboa, Faculdade de Farmácia.Este trabalho visava desenvolver um método simples baseado na espectroscopia infravermelha para a estimativa da concentração de compostos sólidos de formulações farmacêuticas no contexto do desenvolvimento de medicamentos genéricos. O método proposto pode ser extremamente vantajoso uma vez que os recursos necessários para obter uma primeira estimativa quantitativa da formulação requerem apenas o conhecimento dos espectros infravermelhos de cada componente da formulação (não requer um procedimento de calibração). Baseia-se na utilização dos espectros de infravermelhos de componentes puros, no espectro do produto farmacêutico alvo e num algoritmo especialmente concebido com base no pressuposto da lei de Lambert-Beer. O método foi testado com uma formulação (mistura em pó) contendo paracetamol (a substância ativa), cafeína, amido, talco, celulose microcristalina, estearato de magnésio e lactose (o filler). O método proposto (método sem calibração) foi comparado com o método de resolução de curva multivariada (MCR), um método supervisionado que requer uma calibração, e, portanto, a existência de padrões. Portanto, foi produzida uma série de formulações de acordo com um desenho experimental do tipo D-optimal, alterando dentro de certos intervalos a concentração de cada componente (apenas o paracetamol foi mantido constante). Dois conjuntos independentes de formulações foram concebidos: um para calibração e outro para testes. A implementação do MCR e do método sem calibração foi realizada de acordo com diferentes cenários, simulando mais ou menos incerteza no palpite inicial das concentrações dos componentes. Os resultados para o MCR mostram que para este método é fundamental que os espectros dos componentes puros sejam conhecidos e utilizados como constrangimentos, estimando, portanto, apenas as concentrações. A exatidão e precisão das estimativas estava altamente relacionada com as características específicas do espectro de infravermelhos de cada componente. O método sem calibração demonstrou que as estimativas das concentrações dos componentes da formulação eram semelhantes ou mesmo melhores do que as obtidas para o método MCR. Os resultados também demonstraram que a precisão depende de alguma forma do intervalo permitido para cada componente (palpite inicial). A previsão da concentração para cada componente não deve desviar-se acima de 50% do seu valor real para uma estimativa adequada. Em resumo, o método proposto demonstrou ser um excelente método para obter uma primeira estimativa da composição de uma formulação sólida, que pode ser afinada posteriormente utilizando outras técnicas.This work aimed to develop a straightforward method based on infrared spectroscopy for the estimation of solid pharmaceutical formulations compounds concentration in the context of the development of generic medicines. The proposed method can be extremely advantageous as the resources needed to obtain a first quantitative estimation of the formulation require only the knowledge of the infrared spectra of each formulation component (does not require a calibration procedure). It is based on the use of the pure components infrared spectra, the spectrum of the target pharmaceutical product and an especially designed algorithm based on the assumption of the Lambert-Beer’s law. The method was tested with a formulation (powder mixture) containing paracetamol and caffeine (the active substance), starch, talc, microcrystalline cellulose, magnesium stearate and lactose (excipients). The proposed method (calibration-free method) was compared with the multivariate curve resolution method (MCR), a supervised method that requires a calibration with standards. A series of formulations were produced according to an experimental design of the type D-optimal by changing within certain ranges the concentration of each component (only paracetamol was kept constant). Two independent sets of formulations were designed: one for calibration and one for testing. The implementation of the MCR and the calibration-free method were performed according to different scenarios, simulating more or less uncertainty in the initial guess of the component’s concentrations. Results for MCR showed that for this method it was fundamental that the pure components spectra were known and used as constrains, thus, estimating only the concentrations. Accuracy and precision of the estimations were highly related with the specific features of the infrared spectrum of each component. The calibration free method demonstrated that estimations of the formulation components concentrations were similar or even better than those obtained for the MCR method. The results also demonstrated that accuracy was somehow dependent on the allowed range for each component (initial guess). Initial guess of the concentration for each component must not deviate above 50% of its real value for an adequate estimation. As conclusion, the proposed method demonstrated to be an excellent method to obtain a first estimate of the composition of a solid formulation, that can be fined tuned afterwards using other complementary techniques

The cost-utility of telemedicine to screen for diabetic retinopathy in India.

PURPOSE: To assess the cost-effectiveness of a telemedicine diabetic retinopathy (DR) screening program in rural Southern India that conducts 1-off screening camps (i.e., screening offered once) in villages and to assess the incremental cost-effectiveness ratios of different screening intervals. DESIGN: A cost-utility analysis using a Markov model. PARTICIPANTS: A hypothetical cohort of 1000 rural diabetic patients aged 40 years who had not been previously screened for DR and who were followed over a 25-year period in Chennai, India. METHODS: We interviewed 249 people with diabetes using the time trade-off method to estimate utility values associated with DR. Patient and provider costs of telemedicine screening and hospital-based DR treatment were estimated through interviews with 100 diabetic patients, sampled when attending screening in rural camps (n = 50) or treatment at the base hospital in Chennai (n = 50), and with program and hospital managers. The sensitivity and specificity of the DR screening test were assessed in comparison with diagnosis using a gold standard method for 346 diabetic patients. Other model parameters were derived from the literature. A Markov model was developed in TreeAge Pro 2009 (TreeAge Software Inc, Williamstown, MA) using these data. MAIN OUTCOME MEASURES: Cost per quality-adjusted life-year (QALY) gained from the current teleophthalmology program of 1-off screening in comparison with no screening program and the cost-utility of this program at different screening intervals. RESULTS: By using the World Health Organization threshold of cost-effectiveness, the current rural teleophthalmology program was cost-effective ($1320 per QALY) compared with no screening from a health provider perspective. Screening intervals of up to a frequency of screening every 2 years also were cost-effective, but annual screening was not (>$3183 per QALY). From a societal perspective, telescreening up to a frequency of once every 5 years was cost-effective, but not more frequently. CONCLUSIONS: From a health provider perspective, a 1-off DR telescreening program is cost-effective compared with no screening in this rural Indian setting. Increasing the frequency of screening up to 2 years also is cost-effective. The results are dependent on the administrative costs of establishing and maintaining screening at regular intervals and on achieving sufficient coverage