Technical note: estimating longer drug shelf-life with reliability plotting

Two new criteria for the service life prediction of plastics pipes

A new method for the determination of silver in biological samples is presented in this work. The method involves application of dispersive liquid–liquid microextraction (DLLME) employing ammonium O,O-diethyl dithiophosphate (DDTP) as the chelating agent for extraction and preconcentration of silver prior to quantification using graphite furnace atomic absorption spectrometry (GFAAS). Chloroform and acetone were selected as the extracting and dispersing solvent, respectively, at optimized volumes of 80 μL and 500 μL, respectively. The concentration of DDTP and the extraction time were optimized as 0.01% (m/v) and 10 min, respectively. Pyrolysis (1100 °C) and atomization (1800 °C) temperatures were optimized using a L'vov platform treated with 400 μg of tungsten as a permanent chemical modifier. The method was proven virtually free from interference from major constituents of biological samples. A detection limit of 2 ng g−1 was obtained with relative standard deviations better than 13% and an enhancement factor of 70 was achieved. The determined concentrations for Ag in certified reference biological samples were in good agreement with the certified values at a 95% statistical confidence limit. The reported method using DLLME and GFAAS presented good analytical performance for Ag determination when compared to other methods available in the literature.

We wished to test the validity of a stroke probability point system from the Framingham Study for a sample of the population of Copenhagen, Denmark. In the Framingham cohort, the regression model of Cox established the effect on stroke of the following factors: age, systolic blood pressure, the use of antihypertensive therapy, diabetes mellitus, cigarette smoking, prior cardiovascular disease, atrial fibrillation, and left ventricular hypertrophy. Derived from this model, stroke probabilities were computed for each sex based on a point system. The authors claimed that a physician can use this system for individual stroke prediction. The Copenhagen City Heart Study is a prospective survey of 19,698 women and men aged 20 years or older invited to two cardiovascular examinations at 5-year intervals. The baseline examination included 3015 men and 3501 women aged 55 to 84 years; 474 stroke events occurred during 10 years of follow-up. In both cohorts initial cases of stroke and transient ischemic attack recorded during 10 years of follow-up were used. We used the statistical model from the Framingham Study to establish a corresponding stroke probability point system using data from the Copenhagen City Heart Study population. We then compared the effects of the relevant risk factors, their combinations, and the corresponding stroke probabilities. We also assessed stroke events during 10 years of follow-up in several subgroups of the Copenhagen population with different combinations of risk factors. For the Copenhagen City Heart Study population some of the risk factors (diabetes mellitus, cigarette smoking, atrial fibrillation, and left ventricular hypertrophy) had regression coefficients different from those of the Framingham Study population. Consequently, the probability of stroke for persons presenting these risk factors and their combinations varied between the two studies. For some other risk factors (age, blood pressure, and cardiovascular disease), no major differences were found. The recorded frequency of stroke events in subgroups of the Copenhagen population was compatible with the estimated probability intervals of stroke from the Copenhagen City Heart Study and with those from the Framingham Study, but these intervals were very large. The majority of risk factors for stroke identified by the Framingham Study also had a significant effect in the Copenhagen City Heart Study population. The differences found could be due partly to different definitions of these factors used by the two studies. Although estimated stroke probabilities based on point systems from the Copenhagen City Heart Study and the Framingham Study were similar, the points scored in the two systems did not always correspond to the same combination of risk factors. Such systems can be used for estimating stroke probability in a given population, provided that the statistical confidence limits are known and the definitions of risk factors are compatible. However, because of the large statistical uncertainty, a prognostic index should not be applied for individual prediction unless it is used as an indicator of high relative risk associated with the simultaneous presence of several risk factors.

A new method for determining allowable daily intakes

This technical note is mainly concerned with bit rate conditions to stabilize a continuous-time scalar linear control system which transmits its feedback information through digital communication networks. It shows that when a packet is received, not only the bits inside that packet but also the receiving time instant of that packet carry information. The latter could carry a huge amount of information and can be obtained through simply receiving a packet without additional communication cost. Therefore it is an efficient way to encode information into the receiving time instant of a packet. The receiving time instant, however, cannot be accurately controlled by the sensor/sampler which can determine only sampling time instants. The difference between the sampling and receiving time instants of a packet is up to two delays, including the delay to process and encode the packet and the network delay to transmit that packet. These delays cannot be precisely known and have negative effects on the amount of information carried by receiving time instants. Under the boundedness assumption of these delays, this technical note provides some bit rate conditions to guarantee the system's input-to-state stability by making a good use of receiving time instants. Through event-triggering schemes, we realize these conditions which may require much lower stabilizing bit rates than periodic sampling schemes. Simulations are done to confirm the effectiveness of the obtained stabilizing bit rate conditions.

On-line assessment of delivered dialysis dose: Technical Note

In this project, the degradation of synthetic wastewater comprising p-nitro toluene (PNT) is investigated using UV/TiO2 process. PNT as a pollutant has a very harmful effect on the environment and human hormones. TiO2 is one of the best metal oxides it has photo catalyst role. The full factorial design (FFD) of experiment is employed to investigate the effect of working variables including pH, initial dosage of PNT and catalyst concentration. The Analysis of variance (ANOVA) presented a high determination coefficient value (R2 = 0.9876, R2pred = 0.8585, R2adj = 0.9596) for degradation of PNT and acceptable prediction of second-order regression model. The graphical counter plots were used to control the optimum conditions. The operative variables are optimized at [TiO2] = 0.2g/L , pH value of 4, and [PNT] = 50mg/L. These findings suggest that the percentages of degradation and mineralization of PNT at the forecasted optimum conditions after 120 min of reaction were 64 and 55%, respectively.

Policy makers and programme managers require more detailed information on the cost and impact of packages of evidenced-based interventions to save newborn lives, particularly in South Asia and sub-Saharan Africa, where most of the world's 4 million newborn deaths occur. We estimated the newborn deaths that could be averted by scaling up 16 interventions in 60 countries. We bundled the interventions in a variety of existing maternal and child health packages according to time period of delivery and service delivery mode, and calculated the additional running costs of implementing these interventions at scale (90% coverage) in sub-Saharan Africa and South Asia. The phased introduction and expansion of interventions was modelled to represent incremental strategies for scaling up neonatal care in developing country health systems. Increasing coverage of 16 interventions to 90% could save 0.59-1.08 million lives in South Asia annually at an additional cost of US dollars 0.90-1.76 billion. In sub-Saharan Africa, 0.45-0.80 million lives saved would cost US dollars 0.68-1.32 billion. Additional costs for increased antenatal interventions are low, but given relatively high baseline coverage and lower impact, fewer additional newborn lives can be saved through this package (5-10%). Intrapartum care has higher impact (19-34% of deaths averted) but is costly (US dollars 1.66-3.25 billion). Postnatal family-community care, with potential for high impact at low cost (10-27%, US dollars 0.38-0.75 billion), has been neglected. A first phase of scaling up care in 36 high (NMR 30-45) and 15 very high (NMR >45) mortality countries would cost approximately US dollars 0.56-1.10 and US dolars 0.09-0.17 billion annually, respectively, and would avert 15-32% and 13-29% of neonatal deaths, respectively, in these countries. Full coverage with all interventions in the 51 high and very high mortality countries would cost US dollars 2.23-4.37 billion, and avert 38-68% of neonatal deaths (1.13-2.05 million), at an extra cost per death averted of US dollars 1100-3900. Low-cost, effective newborn health interventions can save millions of lives, primarily in South Asia and sub-Saharan Africa. Modelling costs and impact of intervention packages scaled up incrementally as health systems capacity increases can assist programme planning and help policy makers and donors identify stepwise targets for investments in newborn health.

Indigenous micro-organisms often possess the ability to degrade petroleum hydrocarbon (PHC) in polluted soil. However, this process can be improved by supplementing with nutrients or the addition of more potent microbes. In this study, the ability of kenaf-core to stimulate the PHC degradation capability of microbial isolates from PHC polluted soil samples was evaluated. The standard experimental methods used in this study include: the digestion and analysis of the physico-chemical properties of petroleum hydrocarbon contaminated and non-contaminated soil samples; evaluation of petroleum hydrocarbon biodegradation using bio-augmentation and bio-stimulation (with kenaf-core) treatments; and, determination of soil microbial enzyme activities. Results from this study show that K, Na, total nitrogen, organic carbon, exchangeable cations, and heavy metals were found to be significantly (P < 0.05) higher in the polluted soil than in the non-polluted soil. Also, the polluted samples had pH values ranging from 5.5 to 6.0 while the non-polluted samples had a pH of 7.6. The microbial enzyme activities were comparatively lower in the polluted soils as compared to the non-polluted soil. The percentage degradation in the kenaf-core treated samples (AZ1T2—78.38; BN3T2—70.69; OL1T2—71.06; OT1T2—70.10) were significantly (P < 0.05) higher than those of the untreated (AZ1T1—13.50; BN3T1—12.50; OL1T1—10.55; OT1T1—9.50). The degradation of petroleum hydrocarbon in the bio-augmented and bio-stimulated treatments increased with increasing time of incubation, and were higher than that of the untreated sample. Comparatively, the treatment with a combination of kenaf-core and rhamnolipid exhibited a significantly (P < 0.05) higher degradation rate than that of the treatment with only kenaf core or rhamnolipid. While, the bio-stimulated and bio-augmented treatments had appreciable microbial counts that are higher than that of the untreated. In conclusion, the nutrient-supplement with kenaf-core significantly enhanced microbial growth and activities in the soil, thus improving their ability to biodegrade petroleum hydrocarbons in the polluted soils. Thus, supplementing with Kenaf core to encourage microbiological degradation of petroleum hydrocarbon is recommended.

The most common technique used to achieve primary deep biliary cannulation is the standard contrast-assisted method. To increase the success rate and reduce the risk of complications, a wire-guided cannulation strategy has been proposed. Prospective studies provided conflicting results as to whether the wire-guided cannulation technique increases the cannulation rate and reduces post-endoscopic retrograde cholangiopancreatography (post-ERCP) pancreatitis risk compared with the standard method. The objective of this study was to carry out a meta-analysis of randomized controlled trials (RCTs) that compares primary biliary cannulation and post-ERCP pancreatitis rates with the wire-guided method and the standard cannulation technique. Literature searches of electronic databases and online clinical trial registers up to March 2009 were conducted to identify RCTs comparing primary cannulation and post-ERCP pancreatitis rates with the wire-guided method and the standard cannulation technique. A meta-analysis of these clinical trials was performed. Five RCTs were included. Overall, the primary cannulation rates reported with the wire-guided cannulation technique and the standard method were 85.3 and 74.9%, respectively. The pooled analysis of all the selected studies comparing the wire-guided cannulation technique with the standard method yielded an odds ratio (OR) of 2.05 (95% confidence interval (CI): 1.27-3.31). The pooled analysis comparing the post-ERCP pancreatitis rates for the wire-guided-cannulation groups with those for the standard-method groups yielded an OR of 0.23 (95% CI: 0.13-0.41). This meta-analysis shows that the wire-guided technique increases the primary cannulation rate and reduces the risk of post-ERCP pancreatitis compared with the standard contrast-injection method. Further large, well-performed, randomized controlled studies are needed to confirm these findings.

Simple SummaryThe quality of fresh meat largely relates to water-holding capacity (WHC) which is an important attribute associated with consumer acceptance and food-processing technology. Regarding this, the industry requires methods that can easily, with a great precision, determine the WHC of meat and meat products. The EZ-DripLoss method is relatively new gravimetric method that is used for determination of excessive drip in meat. Currently, there is diversity in the literature regarding the use of EZ-DripLoss methodology. Therefore, this technical note aimed to research drip loss in chicken breast meat measured across the period of three days using two different EZ-DripLoss methodologies. In the standardized EZ-DripLoss method, drip loss is calculated by weighing specialized EZ containers, whereas in the modified EZ-DripLoss method drip loss is calculated by weighing samples. This technical note indicates that different EZ-DripLoss methodology results in different drip loss values in chicken breast meat. Therefore, comparisons of the EZ-DripLoss results should be performed with great caution.The EZ-DripLoss method is relatively new gravimetric method that is used for the determination of excessive drip in meat. The literature reports diversity regarding the use of EZ-DripLoss methodology. In the standardized EZ-DripLoss method, drip loss is calculated as the change in the container weight, whereas in the modified EZ-DripLoss method, it is calculated as the change in sample weight. This technical note aimed to research the relationship between these two methods on chicken breast meat (40 broilers from the line Ross 308) during the measurement interval of 24, 48, and 72 h. The results showed statistically a significant positive linear increase in drip loss values regardless of the used method during all of the investigated measurement intervals. At 24, 48, and 72 h of storage, the average drip loss in the weighed samples was 0.77, 1.40, and 2.23 percentage points greater than in the not weighed samples (p < 0.0001), respectively. A strong and positive estimate of correlation coefficients between the drip loss of weighed and not weighed samples was found after 24 h (r = 0.95), 48 h (r = 0.92), and 72 h (r = 0.86). This technical report indicates that the used EZ-DripLoss methodology highly influences the drip loss in chicken breast meat and the comparisons of the EZ-DripLoss results should be performed with great caution.

In some cases, in the Netherlands, an additional layer is being added to the thermocouple, used to measure the rectal temperature in medicolegal death investigations. Because of this deviation from the standard method, questions arose regarding the accuracy and precision of the measured temperature. Therefore, a cooling experiment was carried out on a round body made of agar with an average thermal conductivity of 0.454 W/(m °C) while measuring the temperature with and without an additional layer around the thermocouple for three different starting temperatures: 36, 30, and 27 °C. The results show a significant difference between the measured values for the first 5 min when comparing with and without the additional layer. Further, a decrease in precision is present within the first minutes when using an additional layer. Therefore, it is concluded that it is best to measure the rectal temperature without an additional layer around the thermocouple and caution should be taken when measuring with an additional layer.

Currently all companies are looking for opportunities in the openness of international markets or global markets. Companies that can enter this global market are companies that have comparative and competitive advantages. It is necessary to make an important decision concerning the level or quantity of production for the manufacturing company, the determination of the amount or stock of merchandise for the trading company as well as the level of service production for the service company. One important aspect that needs proper management is the supply problem. One of the local companies that became the focus or object of research in this writing is UD. Mirama located in Gorontalo Province, especially the city of Gorontalo which sells AC electronic goods and TV. just like any other trading company the company is also having trouble determining the amount of merchandise inventory. Because often companies have difficulty in the amount of safety stock that must be prepared at the time of booking so that companies can anticipate the number of fluctuating demand. With this problem it is necessary to apply a method used as corporate guidance to overcome the problem of inventory. The method that will try to use is standard deviation method in determining the amount of safety stock. This method is applied to see how the most optimal security inventory, which is the most economical, in the sense that not too much which means waste or additional costs that are not necessary or not too little which means there is still danger of running out of inventory. By using model of qualitative and quantitative analysis, the result of research analysis from the research object is the application of standard deviation method can be determined how much the safety stock will be held by the company and can cover the occurrence of stock out when demand increase or fluctuation in demand.

The rotationally invariant phase sensitive skew parameter, an indicator of dimensionality of conductivity structure, is a complicated non-linear function of the impedance tensor elements. In the presence of noise in the impedance data, skew can be significantly biased, leading to a false interpretation of dimensionality. Therefore, the probability function distribution of the skew parameter is derived to obtain its confidence limit, rather than treating a conventional linear propagation error. It is well known that the latter is only appropriate if the parameter is a function of independent random variables with small relative errors. The confidence limit is estimated by deriving its conditional probability function in terms of the tensor elements density function, using the Jacobi-matrix transformation of random variables, assuming the tensor elements to be normally distributed random variables. It is shown with synthetic and experimental data that the statistical confidence limit derived here truly reflects a probability range for the skew value. Bias of skew is seen to be significant with a small 5% of random Gaussian noise added to the tensor elements. Considering the 95% confidence limit instead of the measured skew itself results in a plausible approach to analyse dimensionality. The procedure developed here to estimate the confidence limit can also be extended to other functions of the tensor elements.

Does a coexisting anxiety disorder predict persistence of depressive illness in primary care patients with major depression?