Use Of Standard Values Research Articles

Pattern Electroretinogram in Ocular Hypertension, Glaucoma Suspect and Early Manifest Glaucoma Eyes: A Systematic Review and Meta-analysis

To provide standardized confidence limits of the transient pattern electroretinogram (tPERG) P50 and N95 and steady state pattern electroretinogram (ssPERG) amplitudes in normal controls as compared to ocular hypertension (OHT), glaucoma suspect (GS), or early manifest glaucoma (EMG) eyes. The identification of standardized confidence limits in the context of pattern electroretinogram (PERG) might overcome the high intrinsic variability of the measure, and it might lead to a more intuitive understanding of the results as well as to an easier comparison of data from multiple tests, sites, and operators. The study protocol was prospectively registered on the International Prospective Register of Systematic Reviews (ID: CRD42022370032). A literature search was conducted on PubMed, Web of Science, and Scopus. Studies comparing PERG raw data in normal control eyes as compared to OHT, GS, or EMG were included. The risk of bias was assessed using the National Institute for Health and Clinical Excellence quality assessment tool. The main outcome was the P50, N95, and ssPERG amplitude difference between the control and the study groups' eyes. The standardized mean difference was calculated as a measure of the effect size for the primary outcome. A subanalysis was conducted based on the type of electrodes adopted for the PERG measurements (invasive vs. noninvasive). Of the 4580 eligible papers, only 23 were included (1754 eyes). Statistically significant amplitude differences were found in the P50, N95, and ssPERG amplitudes between normal controls and OHT, GS, and EMG eyes. The highest standardized mean difference values were observed in the ssPERG amplitude in all 3 sets of comparison. The subanalysis did not reveal any statistically significant differences between invasive and noninvasive recording strategies. The use of standardized values as the main outcome measures in the context of the PERG data analysis is a valid approach, normalizing several confounding factors which have affected the clinical utility of PERG both for individual patients and in clinical trials. Steady state PERG apparently better discriminates diseased eyes compared to tPERG. The adoption of skin-active electrodes is able to adequately discriminate between healthy and diseased statuses. Proprietary or commercial disclosure may be found after the references.

The Influence of the Choice of a Gaussian Filter on the Determination of Areal Surface Texture Parameters

The areal Gaussian filtering is the current standardized approach for the separation of roughness and waviness components of a surface topography for areal surface measurements and analysis. Although the technical specifications (ISO 25178) recommend а certain nesting index for areal Gaussian filters, the use of standard values is not possible in some cases, particularly when the recommended value exceeds the range of the measurement software. Therefore, it is necessary to find an appropriate nesting index value other than that recommended by the standard. The aim of this study is to investigate the influence of Gaussian filter selection on areal surface texture parameter determination for structured surfaces. The results suggest that the nesting index of a Gaussian filter for areal surface parameter determination and analysis should be at least three times the scale of the coarsest surface structure.

Diagnostic performance of a fully automated chemiluminescent enzyme immunoassay for Alzheimer's disease diagnosis

The variability of Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers (Aβ42, t-Tau and p-Tau) undermines their full-fledged introduction into routine diagnostics and clinical trials. The introduction of automatic systems can improve the diagnostic performance promoting standardization and reducing the impact of preanalytical and analytical factors.Here we assessed the diagnostic performance of a fully automated chemiluminescent enzyme assay (LUMIPULSE) and compared it with that obtained by using the classical manual enzyme-linked immunosorbent assays (ELISAs). Patients were clinically diagnosed as AD (n = 42) and non-AD (n = 38). Clinical diagnosis was confirmed at follow-up. LUMIPULSE Aβ42 was reduced in AD (969.4 ± 329.6 pg/mL vs. 1625.9 ± 745.9 pg/mL, p <0.001), whereas LUMIPULSE t-Tau was increased in AD (768.2 ± 281.0 pg/mL vs. 337.5 ± 159.1 pg/mL, p < 0.001) compared to non-AD patients. Both LUMIPULSE Aβ42 (AUC = 0.78, spec. = 0.74, sens. = 0.76) and t-Tau (AUC = 0.94, spec. = 0.93, sens. = 0.87) showed good accuracy in distinguish AD from non-AD and a high correlation with the manual ELISAs (r = 0.87, p < 0.001 and r = 0.92, p < 0.001, respectively). LUMIPULSE improves clinical accuracy in AD diagnosis, promoting the use of standardized values for CSF biomarkers with a good correlation with classical manual assays.

Multi-level automation of farm management information systems

As innovative information and communication technology (ICT) tools were gradually introduced over the past decades into the agricultural sector, the use of farm management information systems (FMIS) was widely expanded and nowadays are regarded as important tools for managing the agricultural business. Nevertheless, the necessary workload for collecting, aggregating and importing data related to farming activities into a FMIS, is a task which is often time-consuming and farmers are reluctant to perform. The current paper describes the implementation of three automation levels, which enhance a FMIS by providing solutions related to the collection of fragmented-missing data and time-consuming data entry. The three levels involve: (i) the development of a modular FMIS based on future internet technologies, (ii) the use of standard values for assessing the cost of performed agricultural tasks and (iii) automating the process of importing task-related data into a FMIS using tractor’s CAN-Bus ISO 11783 and SAE J1939 communication information. To assess the financial analysis of the developed FMIS, related data were collected, recorded and analysed for an entire growing season, from two distinct crops, i.e. winter wheat and maize. Furthermore, to assess the automated task formulation in the FMIS, machine data were acquired while ploughing with a mouldboard plough. The application proved capable of performing a profitability analysis based on the recorded cost transactions but also based on the information given by the user related to the performed tasks. With the automatically created task, the FMIS gave the possibility to the user to present and process the necessary information with minimum effort.

Alternative Mixed-Integer Linear Programming Formulations for Shell and Tube Heat Exchanger Optimal Design

In a recent article (Goncalves et al., AIChE J. 2017. DOI: 10.1002/aic.15556), we presented a mixed-integer linear programming formulation for the detailed design of shell and tube heat exchangers based on the Kern approach (Kern, D. Q. Process Heat Transfer; McGraw Hill, 1950). The formulation relies on the use of standardized values for several mechanical parts, which we express in terms of discrete choices. Because we aim at having this model used as part of more complex models (i.e., heat exchanger networks synthesis), we identified a need to improve its computational efficiency. In this article, we explore several different modeling options to speed up solutions. These options are based on different alternatives of aggregation of the discrete values in relation to the set of binary variables. Numerical results show that these procedures allow large computational effort reductions.

One company's observations on the implementation of LOPA

Layer of Protection Analysis (LOPA) has gained popularity as a semi-quantitative risk assessment tool, but often unexpected difficulties are encountered when rolling out LOPA. This article discusses the practical aspects of LOPA implementation in Marathon Petroleum Company LP's Refining Organization (MPC Refining). Specifically, it shows how scenarios are selected from a Hazard and Operability Study (HAZOP) and how they are organized for conducting LOPA efficiently, and it discusses whether to conduct LOPA concurrently or after the HAZOP. The article also compares the [cause → consequence] or [consequence → cause] methodology and addresses the implications of combining multiple causes in a single scenario. Another key aspect of LOPA implementation is the set of numerical values used for frequencies, modifiers and risk-reduction factors. The article shows how numerical values should be tied to the risk matrix and how internal consistency is achieved through the use of standardized values and restrictions on the use of frequency modifiers. It discusses potential solutions for cases where the LOPA outcome does not meet the risk target. Finally, the article shows how the use of application standards can supplement LOPA by defining minimum protections and providing standard LOPA scenarios. © 2017 American Institute of Chemical Engineers Process Saf Prog 36: 284–291, 2017

Comparison of father-offspring and mother-offspring associations of cardiovascular risk factors: family linkage within the population-based HUNT Study, Norway

Cardiovascular risk factors are transmitted from parents to offspring; however, the relative contributions of fathers and mothers remain unclear. If maternal exposures during pregnancy influence offspring through the intrauterine environment, associations between mothers and offspring are expected to be stronger than between fathers and offspring. In this family linkage study we compared father-offspring and mother-offspring associations of several cardiovascular risk factors. The study population consisted of 36,528 father-mother-offspring trios who participated at one or more surveys of the HUNT Study, Norway in 1984-86, 1995-97 and 2006-08. Parent-offspring associations were assessed using unstandardized and standardized residuals from linear regression analysis, and possible non-paternity was accounted for in sensitivity analyses. Age- and sex-adjusted parent-offspring associations for anthropometric factors, blood pressure, blood lipids, blood glucose and resting heart rate were largely similar between fathers and mothers. Use of standardized values and analyses adjusted for non-paternity further emphasized this similarity. This study found largely similar father-offspring and mother-offspring associations across all cardiovascular risk factors under study, arguing against strong maternal effects transmitted through intrauterine mechanisms.

Associations between Heat Pain Perception and Pain Severity among Patients with Chronic Pain

The primary aim of this study was to investigate the associations between standardized values of thermal sensory perception and standardized scores of clinical pain among a heterogeneous cohort of adults with chronic pain that included individuals receiving chronic opioid therapy. The study used a prospective design. The study was set in a multidisciplinary pain rehabilitation center at a tertiary medical center. The cohort included 163 patients (female 58%) who met inclusion criteria, and were admitted from March 2007 to June 2008. Using a validated quantitative sensory test method of levels, standardized values of heat pain (HP) perception and cooling detection threshold were obtained 1day following admission. Standardized scores of clinical pain were obtained at admission using the pain severity subscale of the Multidimensional Pain Inventory. At admission, 109 (67%) patients were using opioids, and the mean morphine equivalent dose was 192mg/day. The mean pain duration was 10.5years, and the two most frequent diagnoses were low back pain (29%) and headache (12%). A significant negative correlation was found between pain severity and HP threshold (r=-0.170, P=0.030), where lower values of HP threshold correlated with greater scores of pain severity. Post hoc linear regression analysis showed the association between HP threshold and pain severity retained statistical significance (P=0.039) after adjusting for opioid dose, pain duration and pain diagnosis. The use of standardized values of HP perception and clinical pain may be key methodological approaches for investigating the clinical correlates of HP perception among heterogeneous populations of adults with chronic pain.

Height‐specific body mass index reference curves for Japanese children and adolescents 5−17 years of age

Body mass index (BMI) reference values in consideration of height variation have not previously been reported. This study established height-specific BMI reference curves for Japanese children and adolescents aged from 5 to 17 years. The 2001 nationwide survey data were utilized for the study. First, the range of variation in BMI corresponding to height (mean +/- 2SD) at each age was compared with the range of variation in BMI corresponding to age (from minimum to maximum) at every cm height. Second, various age groups were combined, and percentile values of BMI (3rd, 5th, 15th, 50th, 85th, 95th, and 97th) were calculated for every cm height, regardless of age, and height-specific BMI reference values (males 100-179 cm, females 100-169 cm) were prepared. Variation in BMI due to variation in height at each age was significantly (P <0.05) greater than variation in BMI due to age at every cm height [males, 12.7 +/- 0.4 vs 9.2 +/- 0.4; females, 11.7 +/- 0.8 vs 8.8 +/- 0.3 (mean +/- SE)]. Although the use of standard values established in consideration of age and height is desirable for BMI-based guidelines for determining childhood overweight and obesity, to simplify the procedure for practical use, it is necessary to establish standard values by height, not by age. Height-specific BMI reference curves are useful for BMI-based evaluation of childhood overweight and obesity in the school health service and follow-up of obese children until adulthood.

Decreased 2,3-diphosphoglycerate concentration in low cardiac output patients and its influence on the determination of in vivo p50.

We investigated whether 2,3-diphosphoglycerate (2,3-DPG) is altered in patients with low cardiac output and the influence of its concentration on the calculation of in vivo P(50). Biochemical and blood gas analysis were performed along with the measurement of cardiac output and body temperature in 13 patients submitted to cardiopulmonary bypass surgeries without the use of donor blood. In vivo P(50) was calculated using the measured (P(50m)) and the estimated 2,3-DPG (P(50e)). 2,3-DPG concentration was lower in these patients when compared to the values obtained in normal volunteers (6.9 +/- 2.2 vs. 11.9 +/- 2.4 microm/gHb). P(50m) was lower than P(50e) (21.6 +/- 1.1 vs. 30.1 +/- 1.2 mm Hg) at all time points. Our data show that in patients with low cardiac output, 2,3-DPG concentration is reduced. Therefore, in these patients, the use of standard values for this variable may introduce an error in the calculation of in vivo P(50).

Impacts of model parameter uncertainties on crop reflectance estimates: A regional case study on wheat

This Letter is an attempt to establish the impact of uncertainty on crop structure and soil background on the canopy reflectance estimate thanks to a regional field experiment through which the space and time variability is well known. The error due to the use of standard values is mainly due to soil reflectance in the early growth and to crop structure in the late growth. Vegetation indices, NDVI or TSAVI, reduce the sensitivity to the uncertainty on both parameters depending on the phenological period.

High mineral contents explain the low construction cost of leaves, stems and fruits of tomato plants

The construction cost of plant tissues is used in crop models to convert the products of photosynthesis intobiomass. As for other greenhouse crops, tomato tissues are specific in that they have a high mineral content. The consequences of this accumulation of minerals on the construction cost of the tissues and the possible interactions with the physiological age of the organs and with the CO2 concentration in the atmosphere was examined. For that purpose, threemethods of estimating the construction cost were used and compared. Large quantities of minerals accumulated in the tissues of tomato plants (ranging from 0.05 in fruits to 0.26 g g-1 DM in leaves). The subsequent dilution of the organic matter explained why the estimated construction cost of the dry matter (organic matter+minerals) was fairly low in comparison to that of other crop species. The construction cost was higher in fruits than in vegetative organs, partly because of a lower mineral content. It decreased by 7–12% from top to bottom of the canopy, following the increase in the physiological age of the tissues. This ontogenic drift was partly explained by the accumulation of minerals in the older organs. In the conditions of CO2 enrichment of a commercial greenhouse, no effect of CO2 concentration on the mineral content and on the construction cost of tissues was observed. Such a variability of the construction cost of tomato plant tissues due to the accumulation of minerals or to the ontogeny questions the use of standard values in crop models.

NATIONALSOZIALISMUS ALS THEMA DER DEUTSCHEN NACHKRIEGSPÄDAGOGIK DARGESTELLT AM BEISPIEL “DER SAMMLUNG”

The authors of this article investigate the way in which West German educationists approached National Socialism in the period immediately after the Second World War. They focus on the articles in the Journal “Die Sammlung”, which was published by Herman Nohl from 1945 till 1960, giving a quantitative analysis of the authors who wrote on the subject and the contents of their articles. Dudek and Rauch come to the conclusion that National Socialism was seen as a primarily ethical and moral movement, destroying the mind and making improper use of standard values and ideals.

Postmortem interval estimation from body temperature data only

One of the most consistently used methods of postmortem interval estimation (PMIE) is by means of body temperature measurements. Several variations of this method exist, from simple ‘rules of the thumb’ to quite complex equations requiring a knowledge of body mass and height. All of these methods employ a certain degree of approximation and perhaps the use of standard values and tables, and all of them are susceptible to some degree of error. The present study, at the Department of Forensic Medicine, Leeds, was initiated by the Home Office to investigate the extent of the errors which might be encountered in the use of these methods, and to devise a more simple and accurate method. The method devised is called the time-dependent-z equation, for purely theoretical reasons. It will be referred to as the TDZE method. The TDZE method requires the measurement of two rectal temperatures, about 1 h apart, a little mental arithmetic and reference to a single standard curve. The method is valid for all bodies, obese or emaciated, clothed or naked, in all environmental conditions, without modification. Results of the use of the method on data collected from 67 coroner's cases compare favourably with the results obtained by the use of other methods on the same data.

GLOBAL DISTRIBUTION OF NET RADIATION ACCORDING TO A NEW FORMULA

A new formula for estimating net radiation has been derived from records of solar radiation, humidity, and air temperature. The formula is believed to be an improvement over the previous ones which used cloudiness instead of solar radiation. The correlation coefficient between the computed and actual values is 0.97 and the standard error of estimate is 2.57 langleys/day. The limitations of the formula, such as the use of standard values of reflection coefficients, the use of surface humidity instead of total precipitable water, and the exclusion of carbon dioxide, are discussed. The formula has been applied to 386 stations for the construction of world maps for four mid-season months as well as for the year. The distributional pattern differs somewhat from the world maps prepared by Budyko. Solar radiation retained as net radiation decreases from sixty percent in the tropics to less than twenty percent in high latitudes.

Thermodynamic and kinetic causes of passivity

The transition from an adsorbed oxygen monolayer to the continuous oxide film is emphasized as continuous.The error of the traditional potential calculations for passivating oxide formation is shown to be due to the use of standard value of metal free energy instead of its real value on the outer side of the film.It is shown that the so-called chemical dissolution of the passivating oxide is not a real step that can limit the dissolution rate of the passive metal.The experimental data of the electrochemical behaviour of magnetite are used to show that an electrochemical equilibrium must occur for oxygen in the solution and in the passivating oxide surface. The free energy distribution between the components of the lattice is estimated. Cation transfer into the solution is shown to be the same anodic act on passive metal as on active. Passivation occurs because of an increase in the barrier of this transfer, due to the strengthening of the chemical bonds of the surface cations of the solid phase. The electrochemical stability of passive metal and chemical stability of the passivating oxide are two effects of the same causes.