Modern Formulae Research Articles

Comparison of 2 modern swept-source optical biometers—IOLMaster 700 and Anterion

PurposeTo compare biometric measures from 2 modern swept-source OCT biometers (IOLMaster700 (Z, Carl-Zeiss-Meditec) and Anterion (H, Heidelberg Engineering)) and evaluate the effect of measurement differences on the resulting lens power (IOLP).MethodsBiometric measurements were made on a large study population with both instruments. We compared axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT) and corneal front and back surface curvature measurements. Corneal curvature was converted to power vectors and total power derived using the Gullstrand formula. A paraxial lens power calculation formula and a prediction for the IOL axial position according to the Castrop formula were used to estimate differences in IOLP targeting for emmetropia.ResultsThere were no systematic differences between measurements of AL (− 0.0146 ± 0.0286 mm) and LT (0.0383 ± 0.0595 mm), whereas CCT yielded lower (7.8 ± 6.6 µm) and ACD higher (0.1200 ± 0.0531 mm) values with H. With H, CCT was lower for thicker corneas. The mean corneal front surface radius did not differ (− 0.4 ± 41.6 µm), but the corneal back surface yielded a steeper radius (− 397.0 ± 74.6 µm) with H, giving lower mean total power (− 0.3469 ± 0.2689 dpt). The astigmatic vector components in 0°/90° and 45°/135° were the same between both instruments for the front/back surface or total power.ConclusionThe biometric measures used in standard formulae (AL, corneal front surface curvature/power) are consistent between instruments. However, modern formulae involving ACD, CCT or corneal back surface curvature may yield differences in IOLP, and therefore, formula constant optimisation customised to the biometer type is required.

An ensemble-based approach for estimating personalized intraocular lens power

The fundamental difference between modern formulae for intraocular lens (IOL) power calculation lies on the single ad hoc regression model they use to estimate the effective lens position (ELP). The ELP is very difficult to predict and its estimation is considered critical for an accurate prediction of the required IOL power of the lens to be implanted during cataract surgery. Hence, more advanced prediction techniques, which improve the prediction accuracy of the ELP, could play a decisive role in improving patient refractive outcomes. This study introduced a new approach for the calculation of personalized IOL power, which used an ensemble of regression models to devise a more accurate and robust prediction of the ELP. The concept of cross-validation was used to rigorously assess the performance of the devised formula against the most commonly used and published formulae. The results from this study show that overall, the proposed approach outperforms the most commonly used modern formulae (namely, Haigis, Holladay I, Hoffer Q and SRK/T) in terms of mean absolute prediction errors and prediction accuracy i.e., the percentage of eyes within ± 0.5D and ± 1 D ranges of prediction, for various ranges of axial lengths of the eyes. The new formula proposed in this study exhibited some promising features in terms of robustness. This enables the new formula to cope with variations in the axial length, the pre-operative anterior chamber depth and the keratometry readings of the corneal power; hence mitigating the impact of their measurement accuracy. Furthermore, the new formula performed well for both monofocal and multifocal lenses.

Changes of Anti-tuberculosis Herbs Formula During Past Three Decades in Contrast to Ancient Ones.

To investigate the evolution of herbal medicine in treating tuberculosis (TB) and encourage anti-TB drug discovery and development. In this study, 477 ancient traditional Chinese medicine formulae were collected from the Dictionary of Traditional Chinese Medicine Prescriptions and 172 modern Chinese medicine formulae (from 1986 to 2016) were collected by searching 4 databases: WanFang Data Knowledge Service Platform, China National Knowledge Infrastructure Database (CNKI), China Science and Technology Journal Database (VIP) and Chinese Bio-medical Literature and Retrieval System (SinoMed) in Chinese. We restricted the search to publications in Chinese. Further data analysis was done using the Traditional Chinese Medicine Inheritance Support System version 2 Software. There were 425 herbs in the 477 ancient formulae and 257 herbs in the 172 modern formulae. Half of the top 30 herbs were shared by both modern and ancient prescriptions. They are Radix Ophiopogonis, Astragalus membranaceus, Fritillaria cirrhosa, Dried rehmannia glutinosa, Poria cocos, Angelica sinensis, Prepared rehmannia glutinosa, Platycodon Root, Radix paeoniae alba, Schisandra chinensis, Bighead atractylodes rhizome, Rhizoma anemarrhenae, Cortex lycii radicis and Radix Scutellariae. Only two groups of herbs with a high correlation coefficient were found in both modern and ancient prescriptions, the Dried rehmannia glutinosa with Radix ophiopogonis, and Radix ophiopogonis with Prepared rehmannia glutinosa. There were 9 and 15 core herb combinations in modern and ancient prescriptions, respectively, but no one was found simutaniously in both modern and ancient prescriptions. Although there were wide variations in the herb groups and herb combinations in the formulae, half of the top 30 herbs were found in both modern and ancient prescriptions. The core herb combinations in modern and ancient prescriptions could help us to improve the priscription for treatment of TB.

DERIVING BIOLOGICALLY ACTIVE PEPTIDES AND STUDY Of THEIR QUALITIES

The main component of human health is nutrition which becomes even more important if a person is sick. In the body of cancer patients metabolic processes change, so he/she requires a special diet. Probiotics and short peptides are the integral part of the diet of cancer patients. One of the goals of nutritional support for cancer patients is the visceral protein pool maintenance. In modern formulae for enteral support for cancer patients the protein component can be represented in one of three types: native protein; cow’s milk whey/whole protein peptides; free amino acids. The present article deals with study on biotechnological treatment influence on milk protein controlled hydrolysis process with the aim of deriving biologically active peptides, as well as of studying several qualities: immunomodulatory, cytotoxic, antioxidant and prebiotic. Conditions for enzymic hydrolysis of milk proteins are optimised, which provide deriving biologically active directional peptides. The optimal parameters of hydrolysis conduction are chosen, which provide the polypeptide chain division into peptides and free amino acids, as well as enzymic system was chosen, consisting of chymotrypsin or thermolysin at a temperature of 37±2°C, in the enzyme-substrate ratio of 1 to 50 and process time of 12.00±0.05 h. The qualities of biologically active peptides (immunomodulatory, cytotoxic, antioxidant and prebiotic), derived from milk proteins, are studied. The studies demonstrated that all peptides under study have anti-tumour qualities, at the same time increase in biopeptide concentration causes decrease in the capacity for survival of different line cancer cells

Aminochelate fertilizers: the new approach to the old problem; a review

Abstract Aminochelate fertilizers are the latest novel- ties regarding plant nutrition in agricultural production systems. They are part of the modern formulae of fertiliz- ers which are synthesized based on various amino acids, mainly glycine. In recent years, they have had a rapid growth in the marketplace. Their rapid growth in formula- tions, manufacturing, diversity and application is mainly due to the novel understandings regarding diverse roles of amino acids in plant metabolism. Compared to routine fertilizers or other commercially synthetic chelators such as EDTA; however, aminochelates represent a safer and more efficient form of fertilizer, resulting in better plant performance and less environmental risks. Aminochelates represent effective fertilizers for both soil and particularly for foliar applications. Despite, aminochelates having quickly dominated the fertilizer markets in many coun- tries, there is not enough scientific data and information regarding detailed responses of crops to these types of fer- tilizers. This in part, may be due to their mixed composi- tion of several nutrient elements, giving various nutrients effects, meaning that conducting scientific experiments and concluding remarks, , would be very difficult. This review provides information concerning different aspect of aminochelate fertilizers including their history, struc- ture, types, value and effects on agricultural crops.

Carbon Dioxide Solubility in Beer

The amount of CO2 within a beer is a function of CO2 solubility, which in turn is affected by temperature, containing pressure, and beer composition. Historically, this variable was assessed through empirically derived pressure/temperature charts with the first appearing about 1939. Modern methods often involve empirical or semi-empirical formulas that yield close approximations to the aforementioned charts (at typical storage conditions). Other methods to determine CO2 solubility incorporate additional variables such as extract and alcohol content. Unfortunately, the origin of various pressure-temperature solubility charts contained in ASBC's Methods of Analysis or MBAA's Beer Packaging: A Manual for the Brewing and Beverage Industries, are largely unknown, as are the composition of the beers used to create these charts! This discrepancy results in potentially inaccurate CO2 values for differing beer compositions and is especially problematic when assessing modern methods that incorporate additional parameters. This paper attempts to contrast and compare modern and historical methods while considering the limited CO2 solubility reports in beer and sugar and ethanol solutions. In this paper, the accuracy of CO2 solubility charts and formulas are discussed while considering assumptions reported by the original authors. Finally, modern formulae are used with non-linear optimization techniques to generate the likely composition of the “standard beer” used to construct the original ASBC solubility chart. It appears that a “standard beer” of yesteryear is stronger than an average modern beer with an alcohol content of 4.22% (w/w) and a Real Extract of 5.78°P.

Formulae and lens constants for IOL power calculation on the IOL Master

Optical biometry using the Zeiss IOL Master has become synonymous with measurement precision, simple operation and excellent outcomes. The IOL Master is easy to use, however it is important to understand the procedure and technique and that the measurements are applied to modern formulae using optimized A constants. Following on from ‘Accurate optical biometry using the IOL Master’ ( Millbank, 2011 ), the aim of this article is to discuss and explain the formulae to which the biometry measurements on the IOL Master are applied and to attempt to demystify the commonly misunderstood lens constant' issue.

Wave Transformation and Longshore Sediment Transport Evaluation for the Egyptian Northern Coast, via Extending Modern Formulae*

Studies and evaluations were carried out for the purpose of analyzing satellite measured data, or carrying out preliminary evaluations for the study area, near Port Said. In this study waves were transformed from the offshore area to the nearshore area, and longshore sediment transport quantities and rates were evaluated by applying and adjusting some of the available modern formulae. This was done by calibrating with the available reference data, as given in the literature. Thus, the applicability of such formulae for that area can be checked. Offshore significant wave heights from altimeter measurements, which can be downloaded at www.waveclimate.com, are used in this research for 2003 through 2005. The study domain dimensions are 50 km long offshore and 25 km wide alongshore. Wave nearshore transformation is carried out by using the mathematical Simulating WAves Nearshore model (SWAN) based on seasonal/directional bases. Four seasons are considered, winter, spring, summer, and autumn, representing the whole year. Three bulk-type modern formulae, Coastal Engineering Research Center, U.S. Army Corps of Engineers (CERC), Kamphuis, and Van Rijn, for longshore transport evaluation are applied in the study area. The reference targets used for comparison are based on the literature. Through calibration with the reference targets and among themselves, the study comes up with some correction factors for both CERC and Van Rijn formulae to give quite realistic evaluations for that area. These extended/corrected formulae can also be applied in places with similar conditions to the Egyptian coast.

Space physics coordinate transformations: A user guide

This report presents a comprehensive description of the transformations between the major coordinate systems in use in Space Physics. The work of Russell (1971, Cosmic Electrodyn. 2, 184) is extended by giving an improved specification of the transformation matrices, which is clearer in both conceptual and mathematical terms. In addition, use is made of modern formulae for the various rotation angles. The emphasis throughout has been to specify the transformations in a way which facilitates their implementation in software. The report includes additional coordinate systems such as heliocentric and boundary normal coordinates.