Utilization Values Research Articles

The Economic Burden of Insulin-Related Hypoglycemia in Spain.

IntroductionAn analysis was conducted to estimate the economic burden of insulin-related hypoglycemia in adults in Spain, derived from a novel concept developed for the UK known as the Local Impact of Hypoglycemia Tool.MethodsCosts per severe and non-severe hypoglycemic episode were calculated for patients with type 1 diabetes (T1DM) and type 2 diabetes (T2DM). The costs per episode were applied to the population of adults with T1DM and T2DM using insulin in Spain according to the number of severe and non-severe episodes experienced per year. Costs were calculated using Spanish-specific resource costs and published values for resource utilization, including ambulance, accident and emergency (A&E) department, hospitalization, healthcare professional visits, and extra self-monitoring of blood glucose (SMBG) tests used in the week following the episode. A one-way sensitivity analysis on all model inputs was then performed.ResultsThe cost of insulin-related hypoglycemia in Spain is estimated as €662.0 m per year, €292.6 m of which is due to severe episodes and €369.4 m to non-severe episodes. The cost per episode varies from €1.25 for patients with T1DM and €1.48 for patients with T2DM for a non-severe episode where extra SMBG testing after the episode is the only action taken, to €4378.22 for T1DM and €3005.74 for T2DM for a severe episode that was treated in hospital and requires an ambulance, A&E visit, hospitalization, and a diabetes specialist visit. A reduction in severe and non-severe hypoglycemia rates of just 20% could lead to considerable cost savings of €284,925 per 100,000 general population.ConclusionThis analysis highlights the substantial economic burden of hypoglycemia in Spain, and gives budget holders the ability to assess the costs of new treatments or patient education programs in relation to the potential cost savings due to lower hypoglycemia rates.

Nutrient distribution in a shallow subtropical lagoon, south Brazil, subjected to seasonal hypoxic and anoxic events

ABSTRACT The Conceição Lagoon, located in south Brazil, is a semi-enclosed coastal ecosystem that has seasonal hypoxic and anoxic conditions in its vertically stratified central region, characterized as a site of retention and mineralization of organic matter. This study investigates water column dynamics in the central region of the Conceição Lagoon (CCL) and its relation to physical and chemical variables, in order to understand the hypoxic and anoxic events. Surface, halocline and bottom waters were evaluated at three sampling sites along the CCL. The samples were collected in triplicate during the summer, fall and winter of 2014. Hypoxic and/or anoxic events occurred in the summer (1/21) at the halocline (3 m) and bottom (4 m) waters, and in the fall (2/5) in the bottom water (4.5 m). Positive values of apparent oxygen utilization showed mineralization processes in the halocline and bottom waters. The lowest vertical stratification index was recorded in August (southern winter), which was associated with wind speed (14.7 m.s-1) and direction (southern quadrant). Nutrient concentrations were higher in winter, related to increasing of water mixing. This was the first study to evaluate the dynamics of hypoxic and anoxic events in the CCL and how nutrients respond to the physical structure of the water column.

Economic Evaluation of Bevacizumab for Treatment of Platinum-Resistant Recurrent Ovarian Cancer in Canada.

BackgroundOvarian cancer is a leading cause of cancer-related mortality. Although the disease is relatively rare, it carries a disproportionately large morbidity burden.ObjectiveWe conducted a cost-utility analysis from a Canadian public payer perspective to determine the cost effectiveness of bevacizumab, a newly available treatment option for recurrent ovarian cancer.MethodsUsing a 7-year time horizon, a three health-state cohort-based partitioned survival model was developed to assess the cost utility of bevacizumab plus chemotherapy (BEV) versus chemotherapy alone. We reconstructed individual patient data from published Kaplan–Meier curves. Clinical parameters, including progression-free survival and overall survival, were derived from the AURELIA phase III randomized controlled trial. Costs, resource utilization and utility values from recent Canadian sources were used to populate the model. Results were presented using incremental cost-utility ratios (ICURs). Uncertainty was examined through univariate and probabilistic sensitivity analyses.ResultsThe reconstructed individual patient data matched the AURELIA trial results. Total costs for the BEV and chemotherapy treatment arms were $Can79,086 and $Can54,982, respectively. Total estimated quality-adjusted life-years (QALYs) were 1.1055 and 0.9926 for the BEV and chemotherapy arms, respectively. The ICUR was estimated to be $Can213,424 per QALY gained. At a willingness-to-pay threshold of $Can100,000 per QALY gained, the probability of BEV being cost effective was 0.ConclusionsThe results of our analysis suggest that the addition of bevacizumab to single-agent chemotherapy treatment, while improving patient outcomes, is unlikely to be cost effective in this Canadian patient population. The results also provide some preliminary validation for use of individual patient data-reconstruction techniques in pharmacoeconomic evaluation.Electronic supplementary materialThe online version of this article (doi:10.1007/s41669-017-0030-7) contains supplementary material, which is available to authorized users.

Flexible unbalanced control with peak current limitation for virtual synchronous generator under voltage sags

Virtual synchronous generator (VSG) is grid-friendly for integrating distributed generations (DGs) since it can emulate the operation mechanism of traditional synchronous generator (SG). However, the traditional VSG control strategy, which is mainly suitable for balanced voltage conditions, may lead to power oscillations, current unbalance and even overcurrent under unbalanced voltage sags. To overcome this difficulty, a flexible unbalanced control with peak current limitation for VSG under unbalanced operating conditions is proposed. Based on the basic VSG control algorithm, the control strategy integrates two novel control modules, which are current reference generator (CRG) and power reference generator (PRG). The proposed control strategy can flexibly meet different operation demands, which includes current balancing, constant active or reactive power. And the injected currents are kept within safety values for a better utilization of the VSG power capacity. Furthermore, the experimental platform is built. Experimental results demonstrate the validness and effectiveness of the proposed control strategy.

Effect of seed source and pelleting temperature during steam pelleting on apparent metabolizable energy value of full-fat canola seed for broiler chickens

Eleven canola seed (CS) samples were collected from different commercial feedmills and crushing plants in Australia and analyzed for nutrient profile. Six of these samples were selected to determine the effect of seed chemical composition and pellet temperature (PT) during steam pelleting on apparent metabolizable energy corrected for nitrogen (AMEn) values of CS for broiler chickens using a 6 × 2 factorial arrangement of treatments. The CS samples were incorporated into a corn-soybean meal diet at 15% by replacing energy-yielding ingredients, and diets were steam pelleted at either 75 or 90°C. A total of 420 18-day-old male broiler chicks (Ross 308) was assigned to 14 experimental diets replicated 6 times, with 5 chicks per cage. After a 5-day diet acclimation period from d 18 to 22, excreta were collected for 72 h using the substitution method to determine AME and AMEn. There was no interaction of seed source and PT for ileal digestible energy (IDE), AME, or AMEn values of CS (P > 0.05). PT did not affect energy availability of CS (P > 0.05) but increasing the PT improved the pellet durability index of the diets by approximately 5.0 percentage points. A significant effect of seed source was detected for all the energy utilization values of CS (P < 0.05). The IDE, AME, and AMEn values of seed samples ranged from 5,239 to 5,645, 4,728 to 5,071, and 4,501 to 4,791 kcal/kg of DM, respectively. The mean AMEn values were 4,664 kcal/kg of DM, indicating a 5.7% reduction compared with AME values. There was a negative correlation between protein and fat content of the seeds (r = –0.93, P = 0.001), and, consequently, AMEn (r = –0.32, P = 0.009). AMEn values were positively correlated with fat content of CS (r = 0.649, P = 0.001). These results indicate that fat and protein content and fiber components may have a considerable effect on energy availability of CS for broiler chickens.

Modeling and simulation of a novel 4.5 kWe multi-stack solid-oxide fuel cell prototype assembly for combined heat and power

The United States Geological Survey estimates that over four trillion barrels of crude oil are currently trapped within U.S. oil shale reserves. However, no cost-effective, environmentally sustainable method for oil production from oil shale currently exists. Given the continuing demand for low-cost fossil-fuel production, alternative methods for shale-oil extraction are needed. Geothermic Fuel Cells™ (GFC) harness the heat generated by high-temperature solid oxide fuel cells during electricity generation to process oil shale into “sweet” crude oil. In this paper, a thermo-electrochemical model is exercised to simulate the performance of a 4.5kWe (gross) Geothermic Fuel Cell module for in situ oil-shale processing. The GFC analyzed in this work is a prototype which contains three 1.5kWe solid oxide fuel cell (SOFC) stack-and-combustor assemblies packaged within a 0.3m diameter, 1.8m tall, stainless-steel housing. The high-temperature process heat produced by the SOFCs during electricity generation is used to retort oil shale within underground geological formations into high-value shale oil and natural gas. A steady-state system model is developed in Aspen Plus™ using user-defined subroutines to predict the stack electrochemical performance and the heat-rejection from the module. The model is validated against empirical data from independent single-stack performance testing and full GFC-module experiments. Following model validation, further simulations are performed for different values of current, fuel and air utilization to study their influence on system electrical and heating performance. The model is used to explore a wider range of operating conditions than can be experimentally tested, and provides insight into the competing physical processes at play during Geothermic Fuel Cell operation. Results show that the operating conditions can be tuned to generate desired heat-flux conditions as needed across applications.

Eco-school evaluation beyond labels: the impact of environmental policy, didactics and nature at school on student outcomes

We present results from a large-scale study performed in Flanders, focusing on the effectiveness of the eco-schools project. We surveyed 2152 students and 1374 teachers in 101 primary and secondary schools that are actively engaged in the eco-schools program at different stages (including control schools), focusing on their environmental values, knowledge and motivation. The results show that as the schools progress in becoming a certified eco-school, their students’ environmental outcomes change; the eco-schools project thus clearly has an educational impact. The main effects are observed for theoretical knowledge, and to a lesser extent, applied knowledge. We also observed a drop in utilization values and in amotivation. On the other hand, the controlled motivation of students is stimulated by the project as it is implemented, suggesting that students act pro-environmentally due to external pressures rather than because of intrinsic reasons. We also explicitly moved beyond comparing schools based on their eco-schools labels and studied the process factors that contribute to learning outcomes. Our results highlight the importance of the approach to didactics for environmental education, the making of environmental education policy in the schools, and the presence and use of natural green elements at the school campuses. For each of these school-level variables, the impact on students’ environmental learning outcomes are studied and discussed.

Mitigation strategy towards stabilizing the Electrochemical Interface under high CO and H2O containing reformate gas feed

Despite the enhanced CO tolerance of the high temperature polymer electrolyte membrane (HT PEMFC) technology, the synergistic effect of CO and steam in the anodic reformate gas feed was proven to result in serious performance reduction and operation instabilities, due to the dynamic disturbance of the electrochemical interface (EI). In this work a mitigation strategy is presented by controlling the hydrophilicity of the catalytic layer in order to achieve the optimum structure of the EI. The thin and continuous film distribution of the phosphoric acid (PA) inside the catalytic layer (CL) without blocking the pores is the main characteristic property that determines the good quality of the EI. As shown, a hydrophilic catalytic layer is preferable, since the acid, being at any hydration level, will be able to spread over the catalytic surface aiming to the formation of a thin and continuous film so as to maximize the extend of the EI without blocking the pores of the catalytic layer. This facilitates the uninterrupted transport of protons and the fast diffusion of the reacting gases. Herein, this was accomplished by modifying the surface properties of the CL through the anchoring of pyridine moieties on the MWCNTs, which plays the role of the Pt catalyst support. The basic pyridine moieties enhance the hydrophilicity of the nanotubes through the acid (PA)-base (pyridine) interaction so that the contact angle between a PA drop and the catalytic layer is very close to zero. The good affinity of the PA with the pyridine based catalytic layer secures the PA thin film distribution and continuity. More importantly it is not affected even at high hydration levels of the PA, when the partial pressure of steam is increased at values>20kPa. Otherwise, on conventional C supports, hydrated PA has the tendency to shrink and create ganglia leading to the disruption of the EI. The pyridine modified catalytic layers approach Pt surface utilization values as high as 80% as compared to 50% utilization measured for the case of conventional Pt/C catalytic layers.

Erratum to: Impact of old age on patient-report outcomes and cost utility for anterior cervical discectomy and fusion surgery for degenerative spine disease.

With growing older population and increasing rates of cervical spinal surgery, it is vital to understand the value of cervical surgery in this population. We set forth to determine the cost utility following anterior cervical decompression and fusion (ACDF) for degenerative disease in older patients. Patients undergoing ACDF for degenerative diseases were enrolled into prospective longitudinal registry. Patient-reported outcomes (PROs) were recorded at baseline, 1-year, and 2-year postoperatively. Two-year medical resource utilization, missed work, and health-state values [quality-adjusted life years (QALYs)] were assessed to compute cost per QALY gained. Patients were dichotomized based on age: <65 years (younger) and ≥65 years (older) to compare the cost utility in these age groups. Total 218 (87%) younger patients and 33 (13%) older patients who underwent ACDF were analyzed. Both the groups demonstrated a significant improvement in PROs 2-year following surgery. The older patients had a lower mean cumulative gain in QALYs compared to younger patients at 1 year (0.141 vs. 0.28, P = 0.05) and 2 years (0.211 vs. 0.424, P = 0.04). There was no significant difference in the mean total 2-year cost between older [$21,041 (95% CI $18,466–$23,616)] and younger [$22,669 (95% CI $$21,259–$24,079)] patients (P = 0.27). Two-year cost per QALY gained in older vs. younger patients was ($99,720/QALYs gained vs. ($53,464/QALYs gained, P = 0.68). ACDF surgery provided a significant gain in health-state utility in older patients with degenerative cervical pathology, with a mean cumulative 2-year cost per QALY gained of $99,720/QALY. While older patients have a slightly higher cost utility compared to their younger counterparts, surgery in the older cohort does provide a significant improvement in pain, disability, and quality-of-life outcomes.

Chemical Composition and Nutritional Evaluation of the Seeds of Suaeda salsa (L.) Pall

Chemical composition and nutritional evaluation of the seed of Suaeda salsa were studied. The results indicated that seeds contained 5.35% moisture, 4.76% ash, 25.68% fat, 15.27% fiber, 27.32% protein and 20.11% carbohydrates. Sodium was the predominant element followed by potassium and then calcium. Vitamin C and vitamin E were detected. The amino acid profile compared good with FAO/WHO recommended pattern except for cystine/methionine, isoleucine, tyrosine/phenylalanine and tryptophane. Also, the first limiting amino acid was cystine/methionine. Fatty acid composition showed that linoleic acid was the major fatty acid, followed by oleic acid, palmitic acid, linolenic acid, stearic acid and palmitoleic acid. S. salsa seed was a kind of oil source that could satisfy the standards of modern nutrition towards healthy food and it possesses the development and utilization values.

Evaluation of Processed Rain Tree (Samanea saman) Pod Meal as a Non-conventional Ingredient in the Diet of Catla catla Fry

Rain tree (Samanea saman) is a fast-growing tropical tree, abundantly grown in India under plantation programmes. The present study was carried out to evaluate the effects of processed rain tree pod (RTP) in the diets of Catla catla fry. Chemical analysis results indicated that RTP is a good source of protein (25.2% CP) and energy (4.88 kcal/g), and contains 1–2% of ether extract with 44% PUFA. Additionally, it contained 7.4% tannins, 2.25% saponin, and 1.57% alkaloids. Water soaking followed by autoclaving of raw RTP reduced tannin and saponin contents. Five iso-nitrogenous test feeds were formulated incorporating raw (F1) and differently processed RTP (F2-F5) at 30% level with groundnut oilcake and rice bran as co-ingredients and fed to Catala catla fry reared in indoor FRP tanks for 60d. Results indicated that fish of raw or processed RTP fed groups did not show any significant (P>0.05) differences in survival (98–99%), average weight gain (0.30–0.31 g), FCR (1.11–1.14) and specific growth rate (SGR; 1.76–1.82%/day). Nonetheless, the protein efficiency ratio (PER) and net protein utilization (NPU) values varied significantly (P<0.05) between the raw and processed RTP groups. It is inferred that the tannin, saponin and alkaloid contents in raw RTP are possibly in the safe level when incorporated at 30% level in the diet of Catla fry. Hence, there appears to be further scope to incorporate the processed rain tree pod meal beyond 30% level in the carp feed.

Adaptive Resource Utilization Prediction System for Infrastructure as a Service Cloud.

Infrastructure as a Service (IaaS) cloud provides resources as a service from a pool of compute, network, and storage resources. Cloud providers can manage their resource usage by knowing future usage demand from the current and past usage patterns of resources. Resource usage prediction is of great importance for dynamic scaling of cloud resources to achieve efficiency in terms of cost and energy consumption while keeping quality of service. The purpose of this paper is to present a real-time resource usage prediction system. The system takes real-time utilization of resources and feeds utilization values into several buffers based on the type of resources and time span size. Buffers are read by R language based statistical system. These buffers' data are checked to determine whether their data follows Gaussian distribution or not. In case of following Gaussian distribution, Autoregressive Integrated Moving Average (ARIMA) is applied; otherwise Autoregressive Neural Network (AR-NN) is applied. In ARIMA process, a model is selected based on minimum Akaike Information Criterion (AIC) values. Similarly, in AR-NN process, a network with the lowest Network Information Criterion (NIC) value is selected. We have evaluated our system with real traces of CPU utilization of an IaaS cloud of one hundred and twenty servers.

Enhanced manufacturing storage management using data mining prediction techniques

Performing an efficient storage management is a key issue for reducing costs in the manufacturing process. And the first step to accomplish this task is to have good estimations of the consumption of every storage component.For making accurate consumption estimations two main approaches are possible: using past utilization values (time series); and/or considering other external factors affecting the spending rates.Time series forecasting is the most common approach due to the fact that not always is clear the causes affecting consumption. Several classical methods have extensively been used, mainly ARIMA models.As an alternative, in this paper it is proposed to use prediction techniques based on the data mining realm.The use of consumption prediction algorithms clearly increases the storage management efficiency. The predictors based on data mining can offer enhanced solutions in many cases.

Evaluation of Vehicle Parking Queueing in a National Park: Case Study of the Laurance S. Rockefeller Preserve in Grand Teton National Park

In national parks, there is a tension between providing areas for vehicles and accommodating other visitor activities in the park. This tension often means there is more demand for vehicle parking than the supply can accommodate. This study examined one of Grand Teton National Park’s (GRTE) visitor attractions with visitor parking provided, the Laurance S. Rockefeller Preserve (LSR) in Jackson, Wyoming. With approximately 54 designated parking spots available, a study to determine the queueing theory measures of performance was conducted under observed and higher-value parameters to evaluate the system. It was determined that under the observed average arrival rate of 25 vehicles per hour (vph) and 35 vph with an average service rate (time a vehicle was parked) of 1 h and 20 min, the system resulted in good performance with a facility utilization value of 61% and 84%, respectively. However, under the higher-value parameters, the results were poorer, with facility utilization values greater than 88%. This study provides a reference for the evaluation of performance measures and can be applicable to future changes in the LSR at GRTE, other national parks parking, or in general parking areas where queueing may be anticipated.

Impact of old age on patient-report outcomes and cost utility for anterior cervical discectomy and fusion surgery for degenerative spine disease.

With growing older population and increasing rates of cervical spinal surgery, it is vital to understand the value of cervical surgery in this population. We set forth to determine the cost utility following anterior cervical decompression and fusion (ACDF) for degenerative disease in older patients. Patients undergoing ACDF for degenerative diseases were enrolled into prospective longitudinal registry. Patient-reported outcomes (PROs) were recorded at baseline, 1-year, and 2-year postoperatively. Two-year medical resource utilization, missed work, and health-state values [quality-adjusted life years (QALYs)] were assessed to compute cost per QALY gained. Patients were dichotomized based on age:<65years (younger) and≥65years (older) to compare the cost utility in these age groups. Total 218 (87%) younger patients and 33 (13%) older patients who underwent ACDF were analyzed. Both the groups demonstrated a significant improvement in PROs 2-year following surgery. The older patients had a lower mean cumulative gain in QALYs compared to younger patients at 1 year (0.141 vs. 0.28, P=0.05) and 2 years (0.211 vs. 0.424, P=0.04). There was no significant difference in the mean total 2-year cost between older [$21,041 (95% CI $18,466-$23,616)] and younger [$22,669 (95% CI $$21,259-$24,079)] patients (P=0.27). Two-year cost per QALY gained in older vs. younger patients was ($99,720/QALYs gained vs. ($53,464/QALYs gained, P=0.68). ACDF surgery provided a significant gain in health-state utility in older patients with degenerative cervical pathology, with a mean cumulative 2-year cost per QALY gained of $99,720/QALY. While older patients have a slightly higher cost utility compared to their younger counterparts, surgery in the older cohort does provide a significant improvement in pain, disability, and quality-of-life outcomes.

Seasonal variability of stable carbon isotopes (δ13CDIC) in the Skagerrak and the Baltic Sea: Distinguishing between mixing and biological productivity

We documented the annual cycle of the carbon isotopic composition of dissolved inorganic carbon (δ13CDIC) in the water columns of the Skagerrak and Baltic Sea to obtain an increased understanding of the processes involved controlling the carbon isotopic distribution in shelf seas. The lowest δ13CDIC values (−4.9‰) were found in the low-oxygen, brackish Baltic bottom water whereas the highest values (+1.8‰) were observed in the surface water of the Skagerrak during late summer. Photosynthesis drove the high δ13CDIC values (between 1.0 and 1.8‰) noted in the surface waters of both the Skagerrak and the Baltic. The δ13CDIC values below the halocline in the Baltic reflect mixing of brackish water and the more saline water from the Skagerrak, and foremost organic matter remineralization processes that release significant amounts of low-δ13C CO2. Similarly, in the stagnant fjord basins, little deep water exchange and the degradation of terrestrial and marine organic matter set the δ13C composition. Deep-water renewal in the fjord basins resulted in rapid increases of the δ13CDIC on the order of 1‰, whereas remineralization processes caused a decrease in δ13CDIC of 0.1–0.3‰ per month depending on location. The combined effects of water mixing and remineralization processes (estimated using apparent oxygen utilization (AOU) values) yielded the expression: δ13CDIC=0.032∗S−0.01∗AOU−0.12 for the Baltic – Skagerrak region at water depths below the halocline.

Response of Maize (Zea mays L.) to Moisture Stress under Different Nitrogen Fertilization Levels

Two field experiments were conducted at Farm of Sids Agricultural Research Station, Egypt, during 2013 and 2014 seasons to study the effect of different irrigation regimes (I1 = 100 %, I2 = 85 % and I3 = 70 % from irrigation requirements) and nitrogen levels (90, 120 and 150 kg N fed-1) on maize growth, yield and its yield attributes and some crop-water relationships. The most important results could be summarized as follows:Irrigated maize plants with full irrigation produced higher values of plant height, ear diameter, 100- grain weight, weight of grains ear-1 and grain yield as well as total amount of irrigation water applied, seasonal consumptive use and the net income. Irrigated maize plants with 80 % from irrigation requirements gave the highest values of water use efficiency and utilization efficiency.Supplied maize plants with 150 kg N fed-1 induced highest values of the abovementioned growth, yield and its attributes and net income as well as improve seasonal consumptive use, water use efficiency and utilization efficiency.Irrigated maize plants with full irrigation requirements and supplied with 150 kg N fed-1 produced highest yield and net income of maize plants.

A Review on the Application of Eye-tracking in Design Areas

Objective: This study aims to examine domestic literature on eye-tracking in the design area, and to present new eye-tracking application directions. Background: Eye-tracking was introduced in the experimental psychology field for the first time in the 1950s. Eye-tracking has high utilization values in the design application area because eye-tracking can accumulate data on what people see, providing the quantitative values on eye movement. Method: This study examined the papers published in domestic journals, as well as the papers presented in conferences from 2000 to 2016 through DBPIA. Results: Although the use of eye-tracking technology was slightly meager in the product design area, it has been actively used for the evaluation analyses of preference and attention in architecture/public design. Eye-tracking also presented a method to design advertisement that is helpful to advertisement effect measurement, and product salesin the advertisement design area. Since detail psychological analysis is possible, the application of eye-tracking in the studies related with user interface has been active. Conclusion: The eye-tracking technology is projected to be actively used as a new interface means, such as in helping in disabled peoples communication and in device control, in addition to conventional application areas. Application: This study would be of help to find future research areas of eye-tracking.

Effect of Probiotic or Prebiotic Supplementation on the Productive Performance of Barki Lambs.

This study was carried out to evaluate the impact of dietary supplementation of probiotic (Diamond XP™) T1 or prebiotic (BioBoostTM) T2 on nutrient digestibility, rumen fermentation characteristics, productive performance and economic efficiency of Barki lambs. Lambs in control group offered a concentrate feed mixture (CFM) and clover hay without supplementation while, lambs in treatment (T1) and treatment (T2) were fed CFM supplemented with probiotic or prebiotic at rate of 10 g/ head/ day, respectively. Nine barki male sheep (47kg ± 2.5) were used for running metabolism trail. The animals were allocated into three equal groups. Three ruminally cannulated ewes (45 kg ± 3.2) were used to study the rumen liquor parameter, while growth performance trails were carried out with twenty four growing male Barki lambs (27.5 kg ± 0.75) used to determine the growth performance, feed conversion and economic efficiency.The obtained results could be summarized as follow: Animals given ration supplemented with probiotic recorded the highest values of (p<0.05) digestibility and nitrogen utilization followed by animals given ration supplemented with prebiotic, however those fed control ration had the lowest values. The same trend was observed with TDN and DCP values.No significant (p<0.05) differences among rations in ruminal pH values, were recorded while total volatile fatty acids (VFA’s) concentration and microbial protein synthesis had significantly (p<0.05) increased with probiotic supplement. The control ration recorded the highest ruminal NH3-N concentration. A positive impact of probiotics (DFM) and prebiotic supplementation on nutrient intake, feed conversion ratio and economic efficiency have been recorded. It could be concluded that feeding lambs on rations supplemented with either probiotic (DFM) or prebiotic at 10 g/h/d has beneficial effects on rumen parameters, digestibility coefficients, growth performance and economic efficiency of growing Barki lambs.

Profit management of car rental companies

A car rental company consists of a fleet of available rentable vehicles (waiting to be rented and being rented). We model the company as a family of Birth–Death Processes (BDPs) in equilibrium with finite size, indexed by the company utilization parameter. This metric is the ratio of the primary birth and death rates in these BDPs. Relying on the basic concepts of company information and company entropy (i.e., mean information), we promote a procedure for profit management of car rental companies. The company entropy represents the company uncertainty (i.e., risk); moreover, finding optimal values of company utilization and fleet size leads to a unique management of that uncertainty. Introducing the coefficient of proportionality of a company, as ratio of the renting revenue per vehicle per day and costs per vehicle per day, we obtain an expression for the mean profit per day of a company (i.e., profit attained per day from the average number of simultaneously rented vehicles) as a function of company utilization, fleet size and coefficient. Thus, the profit management procedure reduces to finding optimal values of these three metrics, as the key profit drivers of the rental business. Moreover, an expression for the minimal value of the coefficient is introduced (as a function of the other two metrics), determining the zero mean profit per day. Thereby, the efficiency of the company's fleet is determined as a reciprocal of this minimal value. The developed procedure is illustrated on a company which is represented by the Erlang loss system.