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The article presents an innovative method that was verified in the field. It is aimed to improve the load bearing capacity of airfield pavements, which are one of the elements of the flight safety system. Airfield pavements protect the runway in case when the aircraft is taxiing beyond the runway. Moreover, they are also used to perform starting and landing operations of military aircraft. Due to this, they need to have an adequate load bearing capacity that ensures the safety of performing aircraft flights. Airports cannot afford to be shut down for a long time; thus, it is essential to look for efficient and fast solutions that could improve the load bearing capacity of airfield pavements. The authors suggested to apply geogrid immersed in natural airfield pavement.

The NO-17-A205:2017 “Airfield maintenance in winter. Use of de-icers. Requirements and tests” Military Standard is applicable at Polish Armed Forces airports in the process of winter maintenance of airport pavements, both in the process of supplying airports with de-icing agents based on acetates and formates, as in testing, acceptance and control of de-icing agents based on formates, acetates and urea. After the expiration date of product, the tests specified in NO-17-A205:2017 shall be repeated. Purpose of the research is to determine physico-chemical properties changes of de-icing agents applied on artificial airfield pavements, after its expiration dates. The results of research on physical and chemical parameters of de-icing agents obtained at the stage of delivery and after its expiration dates have been given. The tests included determination of appearance, density, refractive index and pH value measurement, as well as checking the freezing point temperature and, in the case of deicing agents in form of granulate, checking the granules size distribution. The requirements and test methods for deicing agents in accordance with NO-17-A205:2017 are also presented. In case of parameters changes, recommendations regarding further use of these agents shall be made. Positive tests results shall be the basis for extending the shelf life of de-icing products for the next winter season.

The natural airport pavement is formed by an adequate preparation of the ground. It should be adapted or constructed in such a way as to minimize the risk to aircraft in the event of an airplane running off the runway. Research indicates that a significant part of natural airport surfaces in Poland do not meet the requirements for load capacity and require reinforcement. The article presents methodology for reinforcing soils, describes the methods of testing the capacity of natural airport pavements and presents the results of research on the natural airport pavement, in reference to the construction with a cellular geosynthetic (geocell).

The load-bearing capacity of natural airfield pavement has a direct impact on the safety of air operations. Unfortunately, the field tests often indicate that the load-bearing capacity of natural airfield pavements is not sufficient. In this case, it is necessary to reinforce them in order to meet the requirements set out in international documents. It is important that the method of reinforcing the subsoil is fast and as noninvasively as possible. There are many methods of reinforcing the subsoil, however, they are expensive and time-demanding, which involves turning off the airport for a long time. Airfield geocells made of recycled plastics discussed in the article seem to be the optimal solution due to the quick implementation of their application by pressing into the existing natural pavement. The article presents the results of laboratory tests demonstrating that material in question is load-resistant and chemical-resistant, while field studies have confirmed that the airfield geocell made of the plastic in question improves the load carrying capacity of natural airfield pavement.

The anti-skid properties of airfield pavements are one of the crucial factors impacting air traffic safety within the ground manoeuvring area. These values are evaluated directly through an analysis of the pavement macro- and microstructure, based on the friction coefficient measurement. The friction coefficient is a ratio between the pressure force of the wheel on the pavement and the friction force generated on their contact surface. Currently there are numerous devices for continuous measurement of the friction coefficient (Continuous Friction-Measuring Equipment - CFME), which in terms of their basic principle of operation, do not differ significantly from each other. CFME measure the pressure force exerted by the measuring wheel on the pavement and the friction forces on the wheel-pavement contact surface. The ratio of these two values is the friction coefficient. Apart from the similarities, these devices also exhibit difference, important in terms of the obtained values. The differences in the type and size of the used measuring tyre, value of wheel skid relative to the pavement or the pressure in the tyre should be mentioned. The results obtained from the measurements taken with the devices might differ by up to several ten percent, therefore they should not be compared, as well as referenced to the same requirements. At the same time, each of the devices enables the determination of anti-skid conditions of the pavement relative to the requirements set out for a given device type, which allows for the classification of the pavement in this regard. Taking classification into account, it is possible to compare the results obtained from various measuring devices. The article presents an overview of the instruments used for continuous friction measurement on airfield pavements, at the same time discussing the ones used on Polish roads. The authors emphasize the requirements for pavements in terms of roughness, taking into account the type of the used device. Moreover, it presents the test procedure for device with no previously determined requirements, but a need to introduce them to the market.

The article describes natural airport pavements in the aspect of performing air operations. Due to the fact that airfield functional elements are not always located on ground of sufficient bearing capacity, it is necessary to use treatments that increase the strength of weak soils. Various reinforcement technologies are available on today's market, and choosing the right method is not simple and depends on many factors, including the final effect we want to achieve after improvement, availability of technology or economic reasons. The article presents a proposal to strengthen the natural airfield pavements using geogrids (cellular geosynthetics). The influence of the applied technology on the improvement of the natural airfield pavemen at one of the airport facilities is described. The results of field tests including geotechnical wells, DPL and DCP probing as well as static plate load tests (VSS and load tests performed with high weight deflectometer (HWD), were analyzed.

The age of currently operated concrete airfield pavements in Poland exceeds 30 years operation period many times. Such a long working life of airfield pavements forced to search for the efficient and fast technologies of their reconstruction. The article described in detail the technologies of fast reconstruction of airfield concrete slabs using prefabricated slabs. The addressed technology guarantees the reconstruction and even the improvement of the condition of loadbearing capacity of mentioned airfield slabs which was confirmed during laboratory tests, field tests and practically verified in the real operation in the International Airport Kraków-Balice.

Malnutrition and micronutrient deficiencies are significant public health problems in the Central Asian country of Tajikistan, with over 26% of children under age 5 being stunted and 30% being anemic. The Khatlon Province is the country’s largest agricultural area where people are often dependent on home gardens to ensure food security. The proximity of households to resources such as markets, roads, and infrastructure can affect food availability, diets, and diversity of agricultural products for consumption. This study aims to evaluate whether the remoteness of a household affects the production, consumption, and acquisition of specific crops among households in Khatlon Province, Tajikistan. A remote household was defined as one that is distant from markets and the main center of population, difficult to travel to, and has limited resources. This cross-sectional study used a household survey and focus groups to measure crop production, consumption, and food acquisition. Household surveys were administered to 107 households in six Khatlon districts and 15 focus groups were conducted in various rural villages within Khatlon. Data was analyzed using a two-sample t-test for the household surveys and NVivo software for capturing major themes within the focus groups. Results revealed that there was no statistically significant difference when comparing households for remoteness in regard to crop production, frequency of consumption, and acquisition. Frequency of food consumption was similar when comparing remoteness but significantly decreased among all households when the crop was not in season. Programs that increase agricultural knowledge about production and extended growing season are extremely beneficial to improve nutrition in these vulnerable households. Additionally, gender-related concerns were discovered within the qualitative data such as the double burden of working to maintain crops as well as managing a household. Therefore, interventions based around agricultural production and acquisition should target women.

Endothelial function has diagnostic, prognostic and therapeutic significance. A number of non-invasive techniques were introduced for its assessment, including flow-mediated dilation (FMD), finger plethysmography (RH-PAT) and digital thermal monitoring (DTM). All these methods can be performed simultaneously. In addition, various methods for measuring arterial wall stiffness are available such as: pulse wave analysis (PWA), pulse wave velocity (PWV), pulse contour analysis (PCA) and carotid wall distensibility coefficient (DC). Finally, carotid intima-media thickness (cIMT) and ankle brachial index (ABI) are used as surrogate read-outs of atherosclerosis. Here, we briefly describe the advantages, limitations and interrelationships of various methods used for the assessment of endothelial function, arterial stiffness, and present the concept of an integrated evaluation of vascular health based on multiple methods. This strategy may be useful to stratify cardiovascular risk and represents a step towards multiparametric assessment of endothelium for effective endothelium-guided therapy in patients with cardiovascular diseases.

Different chemiluminescence systems based on luminol, permanganate, manganese(IV) and cerium(IV) reagents were compared regarding their sensitivity and selectivity to determine plant polyphenols. Among the seventeen systems tested, Mn(IV)-formaldehyde-hexametaphosphate was considered to be the most suitable for polyphenols detection. The developed flow injection method (FI-CL) based on enhancing effect of polyphenols on Mn(IV) chemiluminescence is characterised by low detection limit of gallic acid (0.02 μg L−1) and high precision (RSD = 1.7%). The calibration graph was linear from 0.1 to 100 μg L−1. The selectivity studies revealed that the FI-CL method ensures accurate determination of the total polyphenols content in food samples. The method was successfully applied to analysis of a variety of plant-derived foods (wine, tea, cereal coffee, fruit and vegetable juices, herbs and spices). The proposed method is superior to conventional spectrophotometric assays due to its higher sample throughput (195 samples h−1), simplicity, sensitivity and, above all, higher selectivity.

This study was conducted to research and develop recommendations for gender transformative approaches that will address misconceptions around food and nutrition, and reducing barriers around dietary diversity within rural Khatlon Province, Tajikistan. Most of the population in Tajikistan live in rural areas and spend a large part of their income on food. While stunting in children under 5 years has decreased, acute malnutrition and the number of underweight children has increased. This is a qualitative, cross-sectional study that involved secondary data analysis, key informant interviews (KIIs), and focus group discussions (FGDs) to gauge appropriate interventions for agricultural extension agents seeking to improve the nutritional outcomes of their communities. In February of 2017, data were collected from 4 KIIs and 15 FGDs that were stratified as mothers with young children, mothers-in-law, and husbands, across 12 different villages. Analysis of the KIIs and FGDs included NVivo software for coding and to uncover the most salient themes and characteristics from each. The participants of this study reported several misconceptions and taboos surrounding certain foods, especially during pregnancy, and food practices for children under the age of 5 years. Results also indicated a household hierarchy of decision-making surrounding food that included who buys, cooks, and decides what to buy. The findings of this study will be used as a springboard to launch gender-responsive and nutrition-sensitive interventions through the local agricultural extension agents.

This study summarizes the results of micropaleontological, sedimentological, and isotope geochemical analyses of cuttings from five deep wells drilled in the Great Salt Lake (Utah, USA). Spanning the last 5.0 million yrs, our environmental history of the Great Salt Lake distinguishes four intervals based on paleobiological and sedimentological characteristics, using a previously developed tephrochronology for age control. For most of its history, the Great Salt Lake Basin has been occupied by a mixture of marsh, shallow lacustrine and sand flat conditions. In contrast, open lake conditions, typical of the Bonneville cycles and the modern Great Salt Lake apparently have only dominated the basin for the past 0.6-0.8 Ma. The two main structural basins in the study area (the North and South Basins) experienced different lacustrine histories. Large but frequently saline lakes occupied the North Basin after about 0.6 Ma. In the South Basin, ephemeral, saline lacustrine conditions started at 2.1 Ma and developed to full lacustrine conditions at 0.3 Ma. Our paleoenvironmental interpretations are broadly consistent with the aquatic palynological records from the same wells, as well as with the prior core- and outcrop-based lines of evidence. However, the differences in lake history between the North and South Basin have not been previously recognized.

Introduction: Flow mediated-dilation (FMD) is a noninvasive test of endothelial function based on shear stressdependent nitric oxide secretion causing vasodilation. Normalization of FMD to shear stress was previously proposed. The aim of present study is an examination of relationship between shear rate and FMD in patients with hypertension and atherosclerosis in comparison with healthy volunteers. Methods: Three groups (11 with essential hypertension, 28 with advanced atherosclerosis and 26 controls) were examined. Flow mediated dilation after 5-minute cuff occlusion and post-deflation shear rate were assessed. Brachial artery diameters and blood velocities were obtained by means of high-resolution ultrasound machine. Results: Positive correlations were found between FMD and shear rate with correlation coefficients depending on the disease. Statistical significance was found in atherosclerosis and control groups. Shear rate stimulus is most effective in healthy controls and least effective in hypertensive patients. Conclusions: Post-ischemic shear rate or shear stress should also be taken into account while evaluating the endothelial function with vasodilation measurements.

In this paper, we present an application which aid an evaluation of the arterial diameter changes, based on ultrasound videos. The designed, implemented and verified algorithm uses the techniques of image processing, image analysis and pattern recognition, such as filtering, profile plot analysis and active contour method. Except determining the artery diameter over time it is also able to retrieve ECG from ultrasound video. The results obtained for both signals are synchronized, therefore it is possible to obtain the artery diameters in R wave points, which is a novel approach. Experiments were performed to assess the software validation by comparing the outcomes obtained with the evaluated algorithm with those manually-acquired - the correlation is high. This is the first stage of the research in which we will build the cardiovascular predictive model to search for the new cardiovascular factors.