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OBJECTIVE The immunological factors have role in the development of preeclampsia. The thymus is one of the main organs of the fetal immune system. The aim of this prospective clinical study was to investigate the association between fetal thymus volume and preeclampsia by adding the 3-dimensional measurement of thymus volume to the routine fetal ultrasound scan at 11-14 week of gestation. STUDY DESIGN Totally 72 pregnant women in their first trimester of pregnancy were included and 3-D fetal thymus volume was measured with sonographic VOCAL programme. All women gestational period was followed. The data of women with preeclampsia (n = 10, study group) and without preeclampsia (n = 62, control group) were compared. MAIN OUTCOME MEASURES Fetal thymus volume, preeclampsia development. RESULTS Fetal thymus volume, mean gestational age at birth and newborn birthweight were found to be statistically lower in cases with preeclampsia compared with those without any complications. When the fetal thymus volume measured by the VOCAL programme in the study group was used as a marker for preeclampsia development, the limit value was 0.0375 cm3; sensitivity was 87.1% and specificity was 50% (AUC 85.3%, P

Perforation is used in multilayer tissue products, such as toilet and kitchen papers, as part of the converting process. Perforation facilitates the detachment of consecutive sheets by the user. The compromise between the strength required to detach a perforated sheet and the strength required to break a sheet affects the perforation efficiency. In this work, the mechanical behaviors of 15 commercial papers from different European producers were studied. A morphological analysis of the materials was performed, followed by the determination of their perforation efficiency (through tensile tests). A qualitative analysis of the cuts quality, along with a quantitative analysis of the same cuts dimensions was performed through an optical system. Finally, the stress concentration in the holes and the influence of the cuts distance were analyzed using a finite element model implemented in Abaqus/Standard finite element software. The results showed that a cut distance of 2.0 mm should not be used in these types of papers, and the perforation efficiency increased with the cut distance, regardless of the number of plies in the toilet paper. The stress concentration factor was also determined to have a limit value of 0.11. Papers above this limit value tear at the perforation line, as desired.

We aimed to determine the contribution of quantitative HBsAg in differentiating chronic infections from chronic hepatitis in HBeAg negative patients with HBV DNA 2000–20,000 IU/ml. A total of 79 untreated HBeAg negative patients were included. Patients were divided into 3 groups based on HBV DNA levels: group 1 (HBV DNA ≤ 2000 IU/ml), group 2 (HBV DNA: 2000–20,000 IU/ml) and group 3 (HBV DNA > 20,000 IU/ml). We collected serum from all patients for quantitative HBsAg analysis. We compared serum quantitative HBsAg levels with biochemical parameters, HBV DNA and liver biopsy results. In this study 46 patients were female and the mean age was 42 years. Serum quantitative HBsAg levels were found to be significantly lower in chronic infections compared with chronic hepatitis. There was a positive correlation between quantitative HBsAg and HBV DNA, ALT (alanine aminotransferase), HAI score (histological activity index), fibrosis score and disease stage. The cut-off level of quantitative HBsAg was determined as 4425 IU/ml to differentiate chronic infection from chronic hepatitis. With the test specificity of 95%, we found quantitative HBsAg cut-off values 1026 IU/ml and 20,346 IU/ml for the diagnosis of chronic infection and chronic hepatitis, respectively. Our study suggests that the quantitative HBsAg ≤ 1000 IU/ml limit value might be used for the diagnosis of chronic infection not only in HBV DNA ≤ 2000 IU/ml but also in patients with HBV DNA between 2000–20,000 IU/ml. In addition, antiviral treatment could be considered in patients with quantitative HBsAg > 20,000 IU/ml and HBV DNA > 2000 IU/ml without further examinations such as liver biopsy.

Context: Rising incidence of hand-arm vibration on dentists is an increasing concern in India. The purpose of this study is to investigate the dose-response relationship derived using ready reckoner and to identify the most practicable exposure action and limit value measure that can be collected to aid in the health assessment of dentists exposed to hand-arm vibration. Aims: The objective of this research is to determine the magnitude of vibration transmitted per day among dentists exposed to the vibrating hand-held tools; To determine the association of the magnitude of vibration transmission with duration of usage and to determine the proportion of Exposure Action Value (EAV) and Exposure Limit Value (ELV) among dentists. Methods and Materials: Using a cross-sectional analysis, this study analyzed the incidence of hand-arm vibration on 92 dentists and measured these results with a ready reckoner. Statistical analysis used: Chi-Square Test was used to test the association of vibration exposure with selected parameters that is of interest such as years of experience, duration of work, vibration magnitude of the instrument. Results: The proximity of middle-aged dentists with more than or equal to 10 years of working experience were found to play a huge role in exposure to hand-arm vibration. Conclusions: This study definitely answers the questions regarding the exposure to hand-arm vibration on dentists. This could be minimized reducing exposure times, health surveillance, improved handpieces and other equipment and improving the overall ergonomics of the workplace. Keywords: Dentistry, Exposure assessment, Handarm vibration, Health surveillance.

One of the conditions for achieving maximum land productivity is optimal soil density. In the Amur Region, ecological compaction thresholds for cereals are 1.0-1.24 grams per cubic centimeter, for soybeans – 1.09-1.25, which corresponds to a normal pressure of 80-120 kilopascals, depending on soil moisture. The authors showed that the tractors used in the Amur Region, acting on the soil, exceed the ecological compaction threshold. (Research purpose) To substantiate the ecological compatibility of mobile fi eld energy, primarily tractors engaged in fi eld work, in terms of the compacting eff ect from the normal load transmitted by their propulsion drive to the soil. (Materials and methods) The authors analyzed the experimental data on changes in density, hardness and resistance of soil to processing. An empirical dependence was obtained for calculating the increase in resistance to soil cultivation from the compaction load in a layer of 0-20 centimeters. (Results and discussion) The authors established an increase in plowing resistance of 12-25 percents at a normal load of 138-170 kilopascals, transmitted by the machine propulsion drive, which corresponded to a soil density of 1.25-1.30 grams per cubic centimeter; at a load of 180-250 kilopascals, the resistance increased by 43-50 percents which was equivalent to a soil density of 1.30-1.35 grams per cubic centimeter; at a pressure of 300-350 kilopascals, these indicators increased by 60-67 percents and up to 1.40-1.45 grams per cubic centimeter; and at 400 kilopascals, they showed an increase in resistance of 70-90 percents which is comparable to a density of 1.48 grams per cubic centimeter. (Conclusions) It was determined that the limit value of the normal pressure under the machine propulsion drive in fi eld work should be limited to 150-175 kilopascals. The ecological threshold of normal pressure was established – no more than 120-135 kilopascals with soil moisture of 20-23 percents which was comparable to the soil density of 1.2-1.25 grams per cubic centimeter. The limiting value of the normal pressure of the propulsion drive on the soil was calculated – 350 Pa, which corresponded to the critical soil compaction of 1.30 grams per cubic centimeter.

Diabetes Mellitus (DM) is currently still a global health problem globally. HbA1c levels are the Gold Standard for the evaluation of glycemic control in patients with DM. This study is a pilot study to find out the description of HbA1c levels of Diabetes Mellitus type 2 (DMT2) people who do not participate in PROLANIS in the working area of ​​Balangnipa Public Health Center, Sinjai Regency. This research method is quantitative descriptive. A total of 29 DMT2 patients who did not take part in PROLANIS were recruited by purposive sampling in November 2019. The instrument used was a sociodemographic questionnaire and HbA1C measuring device with the Hemocue 501 brand and its Cartridge Test. Data analysis was performed using a computer statistical program that assessed by calculating the HbA1c levels obtained in this pilot study. The results obtained are the HbA1c levels in this study are in the range of the most 10.1% - 13.9% ie as many as 16 respondents (55.2%) with a mean ± SD respondent of 10.76% ± 2.30028%. The conclusion is that the HbA1c level in DMT2 patients who did not participate in PROLANIS in the working area of ​​Balangnipa Sinjai Public Health Center in this study was higher than the HbA1c level limit value included in the diabetes category, which was 6.5%.

In France, the implementation of mutant herbicide-tolerant crops and the use of the related herbicides - sulfonylureas and imidazolinones - have triggered a strong societal reaction illustrated by the intervening actions of environmentalist groups illegally mowing such crops. Trials are in progress, and therefore should be addressed the questions of the environmental risks and the toxicity of these herbicides for the animals and humans consuming the products derived from these plants. Regulatory authorities have allowed these mutant and herbicide-tolerant plants arguing that the herbicides against which they resist only target an enzyme found in 'weeds' (the acetolactate synthase, ALS), and that therefore all organisms lacking this enzyme would be endowed with immunity to these herbicides. The toxicological literature does not match with this argument: 1) Even in organisms displaying the enzyme ALS, these herbicides impact other molecular targets than ALS; 2) These herbicides are toxic for animals, organisms that do not possess the enzyme ALS, and especially invertebrates, amphibians and fish. In humans, epidemiological studies have shown that the use and handling of these toxins are associated with a significantly increased risk of colon and bladder cancers, and miscarriages. In agricultural soils, these herbicides have a persistence of up to several months, and water samples have concentrations of some of these herbicides above the limit value in drinking water.

The aims of this study were to determine the concentrations of mercury (Hg) in frozen imported Atlantic mackerel consumed in Istanbul and to predict their potential health consequences. In this study, the concentration of Hg was determined following US EPA Method 7473 (2007) using a direct mercury analyzer (DMA-1). Mercury level of the Atlantic mackerel ranged between 0.045 to 0.065 mg/kg. The mercury levels were well below the limit value of 1.00 mg/kg wet weight (EC, 2006; Turkish Food Codex, 2011) for fish such as mackerel. The potential human health risks of Atlantic mackerel sold in Istanbul were also assessed in terms of Hg levels. The estimated weekly intakes (EWI) of the mercury were lower than established provisional tolerable weekly intakes (PTWI). Target hazard quotient (THQ) values were below 1, indicating that Atlantic mackerel consumption is not a potential health risk in adults and children. According to the amount of Hg, this fish can be consumed safely 3 times a week. Furthermore, it is determined that consumption of fish from the IV. Region 4 times a week will not be a problem because of the low amount of Hg. Our results provide a good tool to determine the Hg exposure of Turkish consumers (adult and children) via Atlantic mackerel consumption in terms of food monitoring and food safety.

Background: Self-medication is the use of drugs and painkillers by manypeople with therapeutic or preventive intent without prior professionaladvice or prescribed by a physician, including adults to treat their selfrecognizeddiseases and symptoms. Objectives: Determine the rate of self-medication practice amonguniversity students and determine the most common area to be selfmedicatedand the most common drug group for self-medication. Subjects and Methods: An analytical cross-sectional study of a randomsample of students attending two branches of college of science (biologyand chemistry) from the period of 10th December 2018 to 15th April2019 through purposive sampling technique to collect responses fromstudents using structured questionnaire which was divided into manysections including demographic details of research participants, historyof taking medication to treat a health problem without a prescriptionat the last month, the reasons of self-medication practice. Sample sizewas 220 university students. All data were entered on Microsoft Excel2010, and managed and analyzed on SPSS version 19. The means andstandard deviations were calculated and both t-test and chi-squaretests were used to identify the associations between variables. Theconfidence level was set at 95%, and the p value of less than 0.05 wasthe limit value of significance. Result: The rate of practicing self-medication was significantly higheramong studied university students and it accounted for (64.1%). Andit was significantly higher in females (62.4%) than males (37.6%). Mostof the self-medications (59.6%) were practiced for the pains originatingfrom head and neck. The vast majority of students (80.9%) significantlywere using analgesics and antipyretic, and most of them (71.6%) werepracticing it at any time during the year. Conclusion: The study concluded that the rate of self-medicationamong university students was at the high level, the self-medicationwas practiced anytime during the year and the use of analgesics wassignificantly dominant among other drug groups. How to cite this article:Noaman AA, Hussein MA, Mohammed SQ.Self-Medication Practices among a Sample ofUniversity Students Attending College of Sciencein Diyala Province. J Adv Res Med Sci Tech 2019;6(3&4): 13-18. DOI: https://doi.org/10.24321/2394.6539.201907

To evaluate the prompt and induced dose rate in backscattering neutron hall for radiation protection and safety management. The dose rates were calculated by Monte Carlo code FLUKA, with the “multi-step” simulation method based on traditional “two-step simulation” method. Operation time of staff workers does not need to be restricted. But with the increase in beam power and irradiation time, serious consideration might need to be taken as the dose rate of samples may be higher than the limit value.

Dozer operators are frequently exposed to whole-body vibration (WBV) during the execution of their work. Occupational exposure to WBV in Indian surface coal mines was evaluated by measuring vibration intensity and duration of exposure. A triaxial accelerometer was placed on the operator seat surface for taking the readings. Based on frequency-weighted root mean square acceleration equivalent to 8-hr shift duration, i.e., (A(8)) all dozer operators have exceeded an Exposure Action Value (EAV) of 0.5 m/s2, and 90% of dozers did not exceed Exposure Limit Value (ELV) of 1.15 m/s2. Based on Vibration Dose Value (VDV (8)), all dozer operators have exceeded Exposure Limit Value (EAV) of 9.1 m/s1.75, but no dozer operators have exceeded Exposure Limit Value (ELV) of 21 m/s1.75. Further, an epidemiological study was performed for identifying the extent of musculoskeletal disorders (MSDs) among dozer operators. For the detailed study, 42 dozer operators and 22 controls were selected from 2 surface coal mines. The control group was not exposed to WBV. It was seen from the cross-sectional study that pain in the lower back was predominantly higher (83.33%) in the exposed group when compared with the control group (31.81%). Likewise, pain in the neck (47.61%), shoulder (42.85%), knees (42.85%), and ankle (11.90%) was higher in the exposed group than that of the control group (22.71%, 0%, 45.45%, and 4.54%). A significant observation among the exposed group was that there was degradation in the quality of life. The outcome of the study would assist in monitoring and mitigation of machinery-induced vibration diseases (MIVD) in India and generally applicable to most of the mechanized mines as well. However, comprehensive studies are still needed to enunciate the magnitude extent.

Purpose Fastener technology is one of the key technologies of the ballastless track structure, and the spring strip is the key component to realize the fastener function. Based on the fatigue test of the WJ-7 type fastener of the ballastless track in China, it is concluded that the fatigue damage of an elastic strip is the main reason for the decline of service performance of the fastener. The purpose of this paper is to discuss the fatigue life of the fastener. Design/methodology/approach First, a DH3818 static strain tester is used to measure the static strain signal in the elastic strip fatigue test, and then the fatigue limit of the WJ-7 elastic strip is calculated. Finally, the fatigue life of the fastener strip is estimated. Findings The findings of the paper are as follows: first, the lowest fatigue life with a survival rate of 99 percent should be taken as a reference for the service times of WJ-7; second, the fatigue life of the modified formula found to be short under the same stress amplitude. Originality/value The fatigue test is processed by the authors and the results of elastic strip are obtained based on the test. Meanwhile, the corresponding limit value of the fatigue stress amplitude is calculated based on the tested results.

This study aims to analyze the legal considerations used by the head of the district court in the adjudicate the auction of execution. The other purpose is to analyze the legal implications related to the enactment of the Security Rights Law and the Minister of Finance’s Regulation on Instructions for Auction Implementation. This study uses normative juridical research with a statute approach and a case approach. The results show that there are three basic considerations used by the head of the district court in determining the object's limit value over the auction of security rights execution. The juridical implication that the head of the district court is wrong in applying Article 6 of the Security Rights Law. The determination of the limit value by the head of the district court contrary to the principle of the judge being passive and waiting.

BACKGROUND Safe exposure levels for industrial chemicals are a prerequisite to the safety of workers in occupational settings. METHODS The application areas of the benchmark dose (BMD) approach have tremendously increased in recent years. Quantitative analyzes of dose-response relationships of genotoxic chemicals are among these application areas too. This study investigates the applicability of sister chromatid exchange (SCE) frequencies in lymphocytes of lead-exposed workers to derive a biological limit value (BLV) for inorganic lead. To this end, our previously published occupational lead exposure data were pooled and re-examined by using the BMD approach. Subsequently, we determined the point of departure (POD) value for lead-induced SCE frequencies in lymphocytes. Accordingly, the blood lead concentrations and SCE frequencies in lymphocytes of 26 control and 108 lead-exposed male voluntary workers employed in a battery manufacturing plant were subjected to BMD modeling to determine the BMD confidence interval (BMD-CI). RESULTS According to our data set, benchmark dose lower bound (BMDL) of 6.55 μg Pb/dL blood for the SCE frequencies in lymphocytes of lead-exposed workers has been obtained. CONCLUSION The blood lead concentration of 6.55 μg/dL might be proposed as the BLV for lead and its inorganic lead compounds based on our dataset.

This study was aimed to determine the difference of the effective dose from the clinical and theoretical on the head CT-Scan examination of adult patients and compare the data with the permitted dose limit from BAPETEN. The data collected at Haji Hospital Surabaya using MSCT Siemens Somatom Definition AS 64 Slice on five adult patients, aged between 28-67 years old. The step before the scanning process were adjusting the voltage (kV) and current values (mA) on the CT-Scan. The scanning duration for each patient was 4s and resulted in head images with CTDIvol and DLP values displayed on the monitor screen. The effective dose limit value for the head CT scan was 2.8 mSv, according to BAPETEN. The study results showed that the effective dose on head CT Scan examination was below the safe dose limit value, while the different fractions between the clinical and theoretical of Patient A, B, C, D, and E was 4.11%; 5.46%; 6.19%; 6.52%; and 5.42%, respectively.

In this study, it was examined effects of climatic and topographic conditions, urbanization and transportation on air quality of Igdir which is the eastern province of Turkey and is an agricultural city. An important part of the city's settlements is on fertile farmland. Air pollutants arising from industry, settlements and transportation show the density on the city center mostly without transcending elevations which have bowl shape and are located around the city during the winter months. Air pollution during the winter months causes a dense fog over the city for weeks under the influence of inversion layer and is reaching significantly amount to effect on human health. Igdir province is located in the orange group (it may occur health implications for vulnerable groups) in terms of EPA air quality index. Also, it is much higher than 80 µg m-3 which is national limit value for PM10. In addition, the average wind speed of Igdir is 1.2 m s-1 and has not enough power to distribute polluted air.

An innovative approach for characterizing the fatigue character of high modulus asphalt concrete (HMAC) and matrix asphalt concrete was presented. Strain-life fatigue equations based on uniaxial tensile test are employed to extract parameters characteristic of the asphalt concrete's resistance to fatigue. The feasible test conditions including specimen size, failure criterion, control mode, loading frequency and test temperature are proposed. In addition, the effect of the mean stress on the fatigue life is analyzed that mean stress has minor influence on fatigue life evaluation. Fatigue strain threshold, limit strain and fatigue life equation are put forward based on the fatigue test results at different strain levels. Such fatigue equation as well as tensile strain threshold and limit value can guide the development of the two asphalt mixtures, which can estimate the lifetime of load-bearing structures. From the fatigue character comparison between the two asphalt mixtures, tensile strain threshold and limit tensile strain of HMAC are smaller than those of matrix asphalt concrete, and HMAC can better resist the fatigue damage than matrix asphalt concrete.

The article describes operating conditions of the railroad dowel used in ZhBR 65 resilient rail fasteners. Requirements for railroad dowel tests in terms of their expediency, possibility to perform such tests and conformity with the actual operating conditions are analyzed. The initiative of the authors, arisen during an analysis of regulatory documents, served as a basis for the studies. Stresses in a dowel and its safety factor in operation and tests were determined analytically by the finite element method, using the APM FEM library, the system of strength analysis for KOMPAS-3D, certified within the GOST-R system. Railroad dowels manufactured by OOO NTT, ZAO Polimer ZAO and Vossloh Fastening Systems GmbH were used as study objects. For the purposes of simulation, 3D models of the corresponding dowels and their mating parts (sleeper, railroad screw, tension clamp, etc.) were built. According to the studies, in tensile tests of dowels, conducted according to Clause 4.6 of Specifications TsP 369 ТU-7, stresses of 85...100 MPa occur in the bodies of all dowels under consideration, which considerably exceed stresses appearing in dowels during operation, and the nature and distribution of such stresses do not correspond to those of operating stresses, the maximum value of which does not exceed 10 MPa. The analysis of stresses arising in sleepers with dowels by the manufacturers under consideration has shown that their limit value is 75 MPa. Besides, in sleepers with dowels by OOO NTT and Vossloh Fastening Systems GmbH, the maximum stresses are in the sleeper body, which allows for their redistribution and prevents dowel pulling-out from a sleeper. Sleepers with dowels made by ZAO Polimer have maximum stresses in the upper face of a sleeper coaxially with the dowel axis, which significantly increases the probability of dowel pulling-out in case of extreme loads.

Stress Corrosion Cracking (SCC) is often identified as one of the predominant failure causes of high-pressure gas transmission pipelines. Long-term operation of pipelines causes degradation of mechanical properties of pipeline steel, including a significant decrease in brittle fracture resistance and resistance to SCC. For oil and gas pipeline steels, there are regulatory requirements for impact toughness, disregarding steel condition, namely as-received or serviced. However, SCC resistance of pipeline steels, being very important for structural integrity, is not regulated. In the present work a new method to evaluate in-service degradation of pipeline steels, taking into account increasing susceptibility of operated metal to SCC, was developed. To ensure a safe operation of gas pipelines, it is suggested that the minimum allowable value of SCC resistance characteristics, in particular, the threshold of J-integral based stress intensity factor for SCC Jscc, should be defined and regulated. It is quite difficult to input these characteristics into regulatory requirements, therefore the developed method is based on modification of regulated limit values of impact toughness for as-received and serviced metal conditions separately, taking into account increasing susceptibility of serviced steel to SCC. The method was applied to evaluate in-service degradation of API 5L X52 ferrite-pearlite pipeline steels. The developed method considers different SCC susceptibility of as-received and serviced pipeline steels and shows there are limitations in regulating the same limit value of impact toughness for as-received and serviced pipeline steels.

Epidemiological studies indicate that radiation damages to the eye lens occurs at lower dose values than previously considered (Worgul et al., 2007; Chodick et al., 2008; Ciraj-Bjelac et al., 2010; Rehani et al., 2011; Vano et al., 2010) [1] , [2] , [3] , [4] , [5] . The International Commission on Radiological Protection lowered the equivalent dose limit value for the eye lens to 20 mSv/year (ICRP, n.d.) [6] . This new limit has been incorporated into the revised Swiss legislation [7] . Prior this change, it was agreed that if the effective dose limit was respected it would implicitly imply the respect of the limit to the eye lens, for penetrating radiation. The concept had to be reviewed in the light of necessary application of the new eye lens dose limit. The new Swiss legislation proposes to use the value of Hp(0.07) measured over the protective apron to estimate the eye lens dose. This study aims to investigate the validity of this approach for medical staff during fluoroscopy guided procedures. The results show that the ratio between thorax and eye lens doses varies greatly from one medical speciality to another, but also between surgeons within the same speciality. Moreover, for a given physician, the ratio varied over the periods of surveillance. Those variations confirmed the crucial influence of external parameters related to experience, practice and workload. The surveillance method is appropriate for most of the procedures performed in the department included in this study. Nevertheless, for the particular configuration in urology, the respect of the effective dose limit measured by the routine dosimetry does not allow direct compliance with the dose limit to the eye lens, unless appropriate protective eye wear gear are worn.

Locomotives must provide a high degree of security and safety in running on any kind of railways, including twisted tracks. Safety against derailment on twisted tracks is evaluated by the limit value of the ratio between transverse guiding force, Y and vertical wheel force, Q. The paper presents a combined method for safety evaluation against derailment on twisted tracks by performing tests on a twisted test stand and on a curved and flat test railway. On the stand with twisted track is measured the minimum forces, Qa,min on the wheels of vehicle. On a curved and flat test railway, with a curve of 150 m, are measured the guiding forces of the leading wheelset. The evaluation of safety against derailment is made by calculation of ratio, (Y/Q)a, for the outer wheel of the leading wheelset. The paper presents the LE Measuring Wheelset designed for electric locomotives and calibrated for simultaneous measurements of the wheel-rail interaction forces in the vertical and transverse directions. Are also presented the tests performed by RRA Bucharest for certification, according to European Technical Specifications for Interoperability, of the LEMA 6000 kW electric locomotive, produced by Softronic Craiova-Romania, from the point of view of the safety against derailment at running on twisted tracks.

As the dangerous level of floor water inrush in Chinese coal field is becoming more and more serious annually, the widely used formulas of broken floor rock mass are belonged to nonlinear type or empirical type. However, they are not well conformed to the practical situation and including mining underground pressure. The biggest depth of broken floor rock mass and the length of gob-floor or mining-floor until the maximum broken floor location are expressed by theoretical formulas on integrity theory. Taking a mining face in Chinese Anhui Province as the object, the relationship between broken floor rock mass and mining underground pressure is studied by numerical simulation, the theoretical analysis, and the DC exploration. The peak and scope of broken floor rock mass will enlarge until reaching limit value with the increasingly advanced distance. The mining gob stress contour is saddle-shaped, and its growing speed is becoming slower, so the 180 m coal mining face has reached the sufficient mining stage. Wave velocity of broken floor rock mass from 0 m to 16 m is greatly decreased by the mining disturbance, and it is basically conformed to theoretical formula and practical situation. The results can be relatively better used in the pressure mining of the Ordovician limestone, because it can provide some safe guarantee for mining deep coal seam.

Natural window ventilation is frequently employed in schools in Europe and often leads to inadequate levels of human bioeffluents. However, intervention studies that verify whether recommended ventilation targets can be achieved in practice with reasonable ventilation regimes and that are also suitable for countries with cold winters are practically non-existent. To explore the initial situation in Switzerland we carried out carbon dioxide (CO2) measurements during the winter in 100 classrooms, most of which (94%) had natural window ventilation. In more than two thirds of those, the hygienic limit value of 2000 ppm specified for CO2 in the Swiss Standard SN 520180 (2014) was exceeded. To improve ventilation behavior, an intervention was implemented in 23 classrooms during the heating season. Ventilation was performed exclusively during breaks (to avoid discomfort from cold and drafts), efficiently, and only for as long as was necessary to achieve the ventilation objective of compliance with the hygienic limit value (strategic ventilation). The intervention included verbal and written instructions, awareness-raising via a school lesson and an interactive tool for students, which was also used to estimate the required duration of ventilation. CO2 exposure was significantly reduced in pilot classes (Wilcoxon signed-rank test, p = 3.815e-06). Median CO2 levels decreased from 1600 ppm (control group) to 1097 ppm (intervention group), and the average proportion of teaching time at 400-1400 ppm CO2 increased from 40% to 70%. The duration of ventilation was similar to spontaneous natural window ventilation (+5.8%). Stricter ventilation targets are possible. The concept of the intervention is suitable for immediate adoption in schools with natural window ventilation for a limited period, pending the installation of a mechanical ventilation system. The easy integration of this intervention into everyday school life promotes compliance, which is particularly important during the COVID-19 pandemic.

The chemical composition of rainwater can serve as an indicator of the excess of acidifying air pollutants. The pH value of rainwater in the presence of sulphur dioxide and nitrogen oxides, the precursors of acid rain, falls below pH 5.6, which is the limit value for acid rain. In this research, the tailoring of halochromic textile was examined for the design of a functional textile that can serve as a sensor and inform the wearer about the presence of pollutants in the air by means of an immediate colour change. For this purpose, a polyamide 6 fabric was dyed with the pH-sensitive Bromocresol green dye, which causes a colour change below pH 3.6 (yellow) and above pH 5.4 (blue). In addition, the dyed polyamide 6 fabric was treated with a water and oil repellent finish. Colour and colour change before and after immersion of unfinished and finished dyed samples in buffer solutions with different pH values were evaluated spectrophotometrically using the CIELAB colour space. The colour fastness to rubbing, washing, and light, and the water and oil repellency of the dyed fabrics were determined according to valid SIST EN ISO standards. The results showed that the unfinished dyed polyamide 6 fabric undergoes a reversible colour change faster and more clearly than the finished dyed polyamide 6 fabric. The dyed polyamide 6 fabric had good colour fastness to rubbing and domestic and commercial laundering, while the colour fastness to light was poor. In addition, the dyed polyamide 6 fabric was pH-sensitive, despite dye degradation under xenon light, regardless of whether it was finished.

Objective To compare recovery of eosinopenia, C-reactive protein (CRP) and procalcitonin levels in predicting the response to treatment in patients with cholangitis. Study design Descriptive, analytical study. Place and duration of study Department of Gastroenterology, Sakarya Training and Research Hospital, Turkey between September 2018 and February 2019. Methodology Patients with cholangitis, who underwent endoscopic retrograde cholangiopancreatography (ERCP), were inducted. Those with choledocholic thiasis alone were considered controls. Eosinophil count above 100.5 cells/µL was the limit value accepted as improvement. ERCP repeat was decided according to eosinophil count below 100.5 and not clinically improving. Relationship between inflammatory markers such as CRP, procalcitonin and eosinopenia values in patients with stone-associated cholangitis was investigated. Results The cholangitis group was comprised of 62 patients [mean age 67±14.57 years; 26 (41.9%) female], while control group was comprised of 57 patients [mean age 57.4±18.10 years; 39 (68.4%) females, p=0.004]. At time of admission, median eosinophils was significantly lower in cholangitis group at 17.50 [9.82-84] ×103/µL compared to control group at 168 [100.11-270] ×103/µL (p=0.001). ERCP were repeated on two patients as their clinical conditions and unremitting eosinophil counts worsened. Eosinophil and CRP markers and clinical improvement were observed after second ERCP procedure. Conclusion Eosinopenia may be used as inflammatory marker in evaluation of response to treatment and for predicting the need to repeat ERCP during clinical follow-up of patients who undergo cholangitis treatment. Key Words: Cholangitis, C-reactive protein, Endoscopic retrograde cholangiopancreatography, Eosinopenia, Procalcitonin.

This article discusses the importance of air quality for the organization and functioning of health resorts. Ten different types of resorts located in various regions of Poland were compared in terms PM10 concentration. Additionally, comparative analysis of the high-PM10 episodes was performed in three urban agglomerations located near the analyzed health resorts. The article also discusses formal, legal, and economic instruments that are the basis for legislative actions as tools for managing the air quality in the selected resorts. The analysis of the average annual concentrations in 2015&ndash, 2019 did not show any exceedances of the PM10 limit value for any of the health resorts studied. High PM10 concentration values in 2018 were recorded for the number of days in exceedance of the limit value, especially in the health resorts of Uniej&oacute, w, Ciechocinek, and Szczawno-Zdr&oacute, j. Health resorts located in the south of Poland were identified as the most at risk in terms of the occurrence of limit value exceedances, information, and alert thresholds. It was concluded that the implementation of the so called &ldquo, anti-smog&rdquo, resolutions, including the development of financial support for changing the heating system to eliminate coal boilers and furnaces, is absolutely necessary for air quality improvement.

In order to accurately analyze the impact load distribution of hydraulic mechanical stepless transmission, the impact load distribution is simulated. Matlab/Simulink software is used to collect the characteristic data of the hydraulic mechanical stepless transmission. According to the collection results, the impact load distribution is judged, the limit value of the load distribution is calculated according to the judgment rule, and the simulation is carried out to realize the accurate simulation of the impact load distribution of the hydraulic mechanical stepless transmission section change. Finally, it is verified by experiments that the numerical simulation results of the impact load distribution of the hydro mechanical stepless transmission section change in this paper are more accurate, more practical and effective than the traditional method, and fully meet the research requirements.

Facial recognition applications are currently being developed because they can be applied in various problem areas such as criminal recognition, security systems, attendance, or human-computer interaction. However, to develop a face recognition-computing model is quite difficult, because the human face presents something complex, so to develop an ideal computing model for human face recognition is quite difficult. One of the best facial recognition methods is the Complete Kernel Fisher Discriminant (CKFD) method. The Complete Kernel Fisher Discriminant (CKFD) method has two advantages when compared to the previous Kernel Fisher Discriminant (KFD). First, the implementation of this algorithm can be divided into two phases, namely Kernel Principal Component Analysis (KPCA) plus Fisher Linear Discriminant analysis (FLD) so that the results are more transparent and simpler. Second, CKFD can make two categories of discriminate information so that the results are stronger. This research aims to produce an application with a face recognition algorithm with CKFD Method that is quite accurate. This research will produce a face recognition application with the CKFD method. The existence of this application is expected to help various parties who need a face recognition process. The CKFD method used can provide excellent facial recognition results when compared to other methods. The best result was given by using limit value with a False Acceptance Rate(FAR) value equal to 3.3 and a False Rejected Rate (FRR) value equal to 36.7.

The human biological monitoring of exposure is the determination of biomarkers, which can be dose biomarkers, measuring internal exposure levels to be compared with any (if known) biological limit value, effect biomarkers, which highlight early symptoms or dysfunctional situations still reversible with the improvement of the exposure situations, and susceptibility biomarkers, which express individual differences of genetic or acquired origin [...]

Occupational exposure to solar UV radiation (UVR) is relevant in the construction sector. We performed a one month monitoring period in late spring of direct individual solar UVR exposure measurements in a group of three construction workers from the Tuscany Italian region, using the GENESIS-UV system for personal dosimetry and for the collection of long-term exposure data in a centralized dataset. Then, we compared personal UVR exposure data with the environmental erythemal dose in the same days in clear-sky conditions. The individual solar UVR exposures of the construction workers in the period between 22nd May and 22nd June 2017 in Tuscany varied between 85.5 and 1556.8 J/m2, while the average daily exposure considering all the three workers resulted 573.3 J/m2. The percentage between individual vs environmental exposure varied from 2.7 up to 31.2%, resulting 12.2 on average. Of the total amount of 40 days/worker measured we detected exposure levels above the 100 J/m2 proposed limit value in 39 days/worker, with exceeding of the limit up to ten times per day, more than five times on average. In terms of cumulative UVR exposure, the construction workers received on average a total one month exposure, based on 21 working days, of 12 kJ/m2, and we estimated an annual exposure of about 70 kJ/m2, approximately corresponding to 700 Standard Erythemal Doses. Our data show that the exposure levels of the Italian construction workers are very high in late spring, systematically exceeding the limit values. These UVR exposure levels can be considered potentially dangerous, in particular if associated with relevant cumulative annual UV doses received at the body, which are related to an increased risk of adverse effects, including skin cancers. Accordingly, a big effort is needed, to urgently reduce occupational solar UVR exposure in the construction sector, improving the application of preventive measures.

Objective Our aim is to test the Nahoum Index as a support in the cephalometric study of vertical dimension and therapeutic orientation in adult patients suffering from Class II malocclusion, deep bite, or short face syndrome. Methods Twenty-three patients with molar Class II and an overbite >4 mm were stratified into two groups: orthodontic (G2) and surgical orthodontic (G1). The ANB angle and Nahoum Index were calculated for cephalometric tracing pre- and post-treatment. The difference between the ANB and Nahoum Index values were analyzed using the Statistical Package for the Social Sciences software. Results In G1, the Nahoum Index decreased from 0.954 to 0.797, and the ANB angle decreased from 5.2° to 3.2°. In G2, the Nahoum Index decreased from 0.825 to 0.817, and the ANB angle decreased from 4.4° to 4°. Conclusion In G1, the difference between before and after treatment was significant for the Nahoum Index only. The difference between before and after values was not significant in the G2 group. It is possible to indicate the Nahoum Index of 0.934 as the limit value in case of which a patient may be treated with orthodontics only. This limit is the opposite of the limit proposed by Nahoum for vertical excess cases and respect the same interval. Therefore, we can consider the range 0.81-0.934 to indicate borderline patients, and >0.934 to indicate surgical patients. If the ratio is close to the normal value as 0.81, the treatment will be orthodontic; if it is further increased, the treatment will be surgical.

Despite a connection between road traffic and air pollution has been clearly identified, few integrated analyses on air quality and mobility policies are currently available worldwide. Aim of this work is to build a framework for the evaluation of the impact of mobility policies on air quality in 14 major Italian cities, on a long-time scale (2006-2016). Air quality data was collected from all PM10, PM2.5, and NO2 monitoring stations, installed in compliance with the European directive 2008/50/EC. A large dataset was collected, including public transport, environmental, and fuel categorization of the private vehicular fleet, low emissions zones and modal split. In the analyzed time period, both public transportation use and private motorization decreased. Considering the environmental classification standards of vehicles, Northern cities are more readily switching to newer and less polluting cars (e.g. Euro 5 and Euro 6). There has been a general reduction in PM and NO2 concentration. Nevertheless, exceedances are still above the targeted limit value, mainly in some Northern cities who made major investments in sustainable and shared mobility: this highlights a strong influence of climatic conditions and other sources. Dramatic variations in the CO/NO ratio were observed in Turin, while smaller changes are observed in Milan, Rome and Palermo.

Single-particle image spot on star map of star sensor can be mistaken for real star image and incur fault star identification, how to treat space single-particle properly in a star sensor is an emerging serious problem. Analysis and modeling are conducted for two types of single-particle image which are of spot shape and stripe shape. By observing two extreme cases of center location (pixel center or corner vertex) of a Gaussian star image and after examining of their Gaussian gray distribution characteristics, the discriminant criterion of single-particle image spot is established with a form of gray interval which is different with the pixel number of connected domains. Another discriminant criterion is also set up according to morphology, which is a limit value calculated from an equation expressing the slenderness of a star image. Simulating test results indicate that the involvement of the discriminant criterion can effectively identify single-particle images from real star ones, which helps to promote the reliability of attitude determination of star sensor.

Background: The use of natural radioactive building materials could be a health risk for both dwellers and mining workers. Therefore, a quick and effective method to test batches of rock samples is needed. Nevertheless, there is no reference value for maximum exhalation rates for building materials, except radiological hazard indices that do not measure gas exhalation rates directly. Objectives: This article investigated the correlations between Gamma Index and radon and thoron exhalation rates, and the proportions of radon and thoron in samples. Moreover, the main objectives were to analyze the feasibility of screening problematic samples for indoor use through a portable radiation detector (CoMo 170), which consists of a quick analysis at very low cost, and to simulate indoor concentration of radon using the measured exhalation rates of dimension stone slabs. Design: Best-selling dimension stone slabs were submitted to the following assays: gamma spectrometry, radon and thoron exhalation analysis using scintillation cell, and radioactivity measurement using a portable detector. Univariate and multivariate statistical analyses were conducted using Statistica 13 software. Results: The average activity concentrations measured were 971 ± 58.6 Bq/kg of 40K, 184 ± 9 Bq/kg of 232Th, and 74 ± 3 Bq/kg of 226Ra. The maximum activity concentrations of 40K, 232Th, and 226Ra series were 1,734 ± 100 Bq/kg, 2,667 ± 109 Bq/kg, and 596 ± 2 Bq/kg, respectively. The average exhalation rate of 222Rn was 406 ± 20 Bq/h m2. Conclusions: The main recommendations arising from this study are as follows: a portable radiation detector (CoMo 170) could be used as a screening method for selected samples; Gamma Index limit value = 1 for dimension stone slabs could be adopted when assessing radon and thoron exhalation; and the surface radon exhalation rate should be measured as a basis of recommendation for surface treatment before sales. Finally, thoron exhalations should be considered in radiological assessment, as 57% of the samples had higher thoron exhalation rates than radon.

Currently, gray water reuse after treatment is emerging as an essential instrument for effective management of water because it promotes preservation of freshwater sources, potentially reduces pollutants in the environment. Appropriate technologies and practices for wastewater treatment for reuse are one way to reduce risks to public health where direct wastewater use is prevalent. One new technology which holds interested of researchers today is called Multi-Soil-Layering system (MSL). This new system is recognized to be efficient, economic, ecological and sustainable technic to treat wastewater. In order to prove his performance in Moroccan conditions, a pilot scale of Vertical Multi-Soil-Layering (V-MSL) was designed and built to treat domestic wastewater (instead of gray water alone) and his performance was investigated. The main treatment performance results showed the high removal rates for the organic matters and nutrients. The quality of the treated wastewater was evaluated according to Moroccan Reject Limit Value (RLV).

The amount of biomass-derived ashes is expected to rise in the EU due to targets to increase the use of renewable energy resources. To promote the reuse of biomass ashes, a regional case study of natural ageing of approximately 1 year was carried out on two landfill fly ash materials originating from wood and wood/peat. The results showed that leaching behaviour differed considerably between the fly ashes. Natural ageing had beneficial effects on the leaching properties of wood fly ash. The leached concentrations of sulphate, chloride, Cr and Mo decreased significantly in this residue. In peat and wood-derived fly ash, natural ageing decreased the leaching of Cr, but had no significant effect on the leaching of Mo and chloride. It was also notable that the leaching of sulphate increased in wood/peat fly ash by more than 130%, exceeding the upper limit value given in national legislation for a paved structure. To comply with the limit values of national legislation concerning the recovery of waste in earth construction, natural ageing alone was not shown to be a sufficient method to reduce the leaching of harmful elements in biomass-derived fly ashes and, thus, further treatments are required.

Bei Oberbauten mit Fester Fahrbahn müssen die vertikalen Schienenstützpunktkräfte im Bereich von Bauwerksfugen nach aktuellem Stand der Technik gemäß den Angaben der Anlage 29 der DS 804 nachgewiesen werden. Aufgrund des nicht-linearen Steifigkeitsverhaltens neu entwickelter Sonderstützpunkte für Brücken sind die auf linearen Steifigkeiten basierenden Regelungen der im Jahr 2000 veröffentlichten Anlage 29 kritisch zu hinterfragen. Im vorliegenden Beitrag werden sowohl die Grundlagen als auch die Ermittlung und die Auswertung von sogenannten j-d-Diagrammen vorgestellt, welche über lineare und nicht-lineare Grenzwertbetrachtungen hergeleitet wurden. Mithilfe der Diagramme kann eine Bewertung des aktuell gültigen Nachweisformates erfolgen. Gleichzeitig wird durch die dargestellten Grenzräume eine vereinfachte Bestimmung der zulässigen Bauwerksverdrehungen und -verformungen ermöglicht.

Introduction: Pesticides are extensively used in agriculture to control harmful pests and prevent crop yield losses or product damage. In Tanzania several studies have been conducted on health effects of pesticides on agricultural workers. However, there are few studies on neurological health symptoms associated with pesticide exposure in flower and onion farms. Objective: The objective of this cross-sectional study was to assess health symptoms associated with pesticide exposure among flower and onion pesticide applicators in the Arusha region, Tanzania. Methods: Data on demographic variables and health symptoms associated with pesticide exposure were collected from 140 males who were employed in spraying pesticides on flower and onion farms in Arusha, Meru and Karatu districts between April and May 2017. The study participants were interviewed using a structured questionnaire with questions focusing sociodemographic characteristics, occupation, pesticide exposure, common type of pesticide used in the area and neurological symptoms experienced during and after pesticide spraying. To determine the intensity of pesticide exposure, acetylcholinesterase assay was done by using the Test-mate Model 400 device with a photometric sensor. Results: Ninety-five percent of pesticide applicators reported handling organophosphate pesticides. Body weakness was the most frequently reported neurological symptom (57.1%) followed by perspiration and headache (40.7%), poor appetite and depression (29.3%) and irritation (26.4%). About 27% of pesticide applicators had an acetylcholinesterase level below the limit value. Conclusion: A high proportion of neurological health symptoms and cholinesterase test depression was noted among pesticide applicators in both farms. There is a need to conduct further studies to ascertain causality for such high instances of neurological symptoms.

Background and objectives: Occupational exposure to waste anesthetic gases in operating room without active scavenging system has been associated with adverse health effects. Thus, this study aimed to compare the trace concentrations of the inhalational anesthetics isoflurane and sevoflurane in operating room with and without central scavenging system. Method: Waste concentrations of isoflurane and sevoflurane were measured by infrared analyzer at different locations (near the respiratory area of the assistant nurse and anesthesiologist and near the anesthesia station) and at two times (30 and 120 min after the start of surgery) in both operating room types. Results: All isoflurane and sevoflurane concentrations in unscavenged operating room were higher than the US recommended limit (2 parts per million), regardless of the location and time evaluated. In scavenged operating room, the average concentrations of isoflurane were within the limit of exposure, except for the measurements near the anesthesia station, regardless of the measurement times. For sevoflurane, concentrations exceeded the limit value at all measurement locations and at both times. Conclusions: The exposure to both anesthetics exceeded the international limit in unscavenged operating room. In scavenged operating room, the concentrations of sevoflurane, and to a lesser extent those of isoflurane, exceeded the recommended limit value. Thus, the operating room scavenging system analyzed in the present study decreased the anesthetic concentrations, although not to the internationally recommended values. Resumo: Justificativa e objetivos: A exposição ocupacional aos resíduos de gases anestésicos em salas de operação (SO) sem sistema ativo de exaustão tem sido associada a efeitos adversos à saúde. Assim, o objetivo do estudo foi comparar os resíduos dos anestésicos inalatórios isoflurano e sevoflurano em SO com e sem sistema de exaustão. Método: Concentrações residuais de isoflurano e sevoflurano foram mensuradas por analisador infravermelho em diferentes locais (próximo à área respiratória do auxiliar de enfermagem e do anestesiologista e próximo à estação de anestesia) e em dois momentos (30 e 120 min após o início da cirurgia) em ambos os tipos de SO. Resultados: Todas as concentrações de isoflurano e sevoflurano nas SO sem sistema de exaustão foram mais elevadas em relação ao valor limite recomendado pelos EUA (2 partes por milhão), independentemente do local e momento avaliados. Nas SO com sistema de exaustão, as concentrações médias de isoflurano ficaram dentro do limite de exposição, exceto para as mensurações próximas à estação de anestesia, independentemente dos momentos avaliados. Para o sevoflurano, as concentrações excederam o valor limite em todos locais de medição e nos dois momentos. Conclusões: A exposição a ambos os anestésicos excedeu o limite internacional nas SO sem sistema de exaustão. Nas SO com sistema de exaustão, as concentrações de sevoflurano, e em menor extensão as de isoflurano, excederam o valor limite recomendado. Dessa forma, o sistema de exaustão das SO analisado no presente estudo diminuiu as concentrações dos anestésicos, embora não tenha reduzido a valores internacionalmente recomendados. Keywords: Inhaled anesthetics, Operating rooms, Indoor air pollution, Occupational exposure, Palavras-chave: Anestésicos inalatórios, Salas cirúrgicas, Poluição do ar em ambientes fechados, Exposição ocupacional

Easy-to-use verification equations are available for the verifications in the simplified calculation method. This applies also for the structural fire design of those masonry types for which a verification with the utilisation factor αfi is given in the National Annex DIN EN 1996-1-2/NA. In specific applications, however, a classification can only be made applying the utilisation factor α6,fi. In these cases, the verification for the structural fire design by calculation is considerably more complex than the mathematical verification of the structural design in the ”cold state“. The present paper shows how the design equation for α6,fi can be made significantly easier with regard to its application by reference to the design value of the vertical load bearing resistance in the simplified method. Moreover, an upper limit value for the utilisation factor α6,fi for the simplified method is summarised in tables.

In Lithuania’s case, the legal requirements for the building acoustic quality since the year 2004 has been ex­pressed through the sound classification scheme (SCS). The relationship of the subjective indoor acoustic comfort with the value of objective sound insulation was considered as a core for the classification scheme. SCS was designed to pro­vide at least one sound class as a request for the newly erected building, other lower classes for reconstructed buildings and higher classes for premises with enhanced acoustic comfort. The adopted scheme contains five sound classes with various steps between them and is based on rating by two different sound insulation descriptors both having the same limit value. A request to protect against noise for newly erected and reconstructed buildings was enforced via the man­datory pre-completion acoustical testing. The database collected during testing allowed for the analysis of about 2000 in situ measurements of sound insulation properties of building partitions. It showed that the possibility of selecting either of the two airborne sound insulation descriptors Dn,T,w or R’w ensures better conformity with subjective comfort percep­tion. This paper also addresses the particularities and advantages of simultaneous application of two different descriptors for regulation of sound insulation performance of dwellings.

Ga-68-labeled radiotracers, particularly used for the detection of neuroendocrine tumors by means of Ga-68-DOTA-TATE or -DOTA-TOC or for the diagnosis of prostate cancer by means of Ga-68-labeled antigens (Ga 68-PSMA), become increasingly important. In addition to the high sensitivity and specificity of these radiopharmaceuticals, the short-lived radionuclide Ga-68 offers almost ideal nuclear characteristics for use in PET. Ga-68 is obtained from a germanium-gallium-generator system, so that the availability of Ga-68-labeled radiotracers is independent of an on-site-cyclotron regardless of the short half-life of Ga-68 of about 68minutes. Regarding the disposal of the radioactively contaminated waste from the preparation of the radiopharmaceutical, the eluted Ga-68 has to be considered to be additionally contaminated with its parent nuclide Ge-68. Due to this production-related impurity in combination with the short half-life of Ga-68, the radioactive waste has to be considered to be contaminated with Ge-68 and Ga-68 in radioactive equilibrium (hereafter referred to as Ge-68+). As there are no clearance levels for Ge-68+ given in the German Radiation Protection Ordinance, this work presents a method to calculate the missing value basing on a recommendation of the German Radiation Protection Commission in combination with simple geometric models of practical radiation protection. Regarding the relevant exposure scenarios, a limit value for the unrestricted clearance of Ge-68+ of 0.4 Bq/g was determined.

TC4 thin-walled parts with curved surface are widely used in industrial applications, and the surface quality is a basic requirement to ensure the functional performance. Because of the low rigidity of thin-walled parts, the cutting vibration problem is commonly encountered which results in a bad surface quality. Meanwhile, the rigidity of the workpiece is continuously changing along with the cutting process which is sensitive to the thin-walled parts and induces a more complex cutting vibration. With the extensive usage of high-speed milling which has the advantage of small milling force, the cutting vibration becomes more severe due to the high frequency excitation for the thin-walled parts. To avoid the serious cutting vibration as well as improve the machining quality for high-speed milling of TC4 thin-walled parts with curved surface, the appropriate cutting parameters which influence cutting vibration directly are needed to be determined. Taking high-speed flank milling of TC4 arc-shaped thin-walled parts as an example, the stable domain is worked out on considering the rigidity variation of thin-walled parts. Meanwhile, the limit stable axial cutting depth is obtained based on the stability domain which is established by considering the rigidity variation of workpiece along with the machining process. The results show that the limit stable axial cutting depth is 9.69 mm, and the stable cutting process as well as the high-efficiency machining can be guaranteed simultaneously when selecting the axial cutting depth that is slightly smaller than the limit value. This research puts forward an effective approach for recognizing the stable axial cutting depth range for high-speed milling of thin-walled parts with curved surface. In addition, it provides guidance for superior-quality and high-efficiency machining process.

Determination of preoperative prostate-specific antigen (PSA) value is primary procedure in diagnosis of different pathological prostate changes (prostate cancer-PC, prostatic intraepithelial neoplasia-PIN and benign prostatic hyperplasia-BPH), followed by digital rectal examination and prostate biopsy as gold standard. Disadvantage of high sensitivity and low specificity of PSA testing in diagnosis of PC is a problem in clinical practice. Aim was to determine the diagnostic performance of PSA in diagnosis of PC, PIN and BPH. The study included 100 patients divided into three groups: 70 with PC, 20 with a PIN and 10 with BPH. Patients with PIN and BPH were control group. Preoperative PSA values were determined by Tandem-R, The patients were divided into subgroups by baseline PSA level as follows: 4-10, 11-20, 21-30, 31-40 and> 40. The definitive histopathological diagnosis was made on routine hematoxylineosin slides. The area under the receiver operating characteristic curve (ROC), sensitivity-SE and specificity-SP of each PSA level were evaluated for PC. Preoperative serum PSA levels in patients with PC (median-35.82 ng/ml, min-6 ng/ml, max-960.40 ng/ml) were significantly higher than with PIN (median-9.15 ng/ml, min-3.16 ng/ml, max-27.61 ng/ml) and BPH (median-8.68 ng/ml, min-0.80 ng/ml, max-31.20 ng/ml). The best diagnostic characteristics of the PSA are on limit value 10 ng/ml (AUC=0.781, SE=92.9%; SP=63.3%; p

Many methods used for traffic signal timing are useless if the conditions in the intersection are oversaturated. With an increase in the number of vehicles, the saturation degree approaches or exceeds the limit value at intersections. This creates a scenario where many signal timing methods become overwhelmed. In this paper, the elimination pairing system – a new method for designing traffic signal timing at oversaturated intersections – is expressed. An object function with vehicle delay and stop-start numbers has been generated. Total cost value has been calculated according to the object function. Obtained results were compared with Webster as a traditional traffic signal timing design method and Transyt 14 signal timing software. While Webster gives exaggerated results, Transyt 14 and Elimination Pairing Systems provide better results. As a result of this study, the elimination pairing system could be used for optimizing the traffic signal timings.

Objective: To evaluate the effects of occupational exposures to coke oven emissions (COEs) and benzo[a]pyrene (B[a]P) on the prevalence of hypertension and abnormal electrocardiogram (ECG) in coke oven workers. Methods: We included 880 coke oven workers and 710 oxygen employees in the exposed and control groups, respectively. Blood pressure (BP), ECG, blood lipid levels, and glucose levels of all subjects were measured. COE and B[a]P concentrations at the bottom, side, and top of the oven and control plants were estimated by weighing and high-performance liquid chromatography. Results: The COE concentration at the top and side was higher than that at the bottom (P < 0.05). The levels of B[a]P at the top and side significantly exceeded the limit value. Abnormal BP, ECG, the detection ratio of hypertension and left ventricular high voltage were significantly greater in the exposed group than in the control group (P < 0.05). The logistic regression analysis results revealed that age and B[a]P exposure were risk factors for hypertension in coke oven workers (P < 0.05) and both were risk factors for abnormal ECG (P < 0.05). Moreover, B[a]P exposure, age, and gender were risk factors for impaired fasting glucose in coke oven workers (P < 0.05). Conclusions: B[a]P and COE exposures are risk factors for hypertension and abnormal ECG in coke oven workers.

In this study a hybrid energy dissipation device is developed by combining a steel slit plate and friction pads to be used for seismic retrofit of structures, and its effectiveness is investigated by comparing the life cycle costs of the structure before and after the retrofit. A hybrid damper is manufactured and is tested under cyclic loading. It is observed that the damper shows stable hysteretic behavior throughout the loading history, and that the cumulative ductility ratio obtained from the experiment far exceeds the limit value required by the AISC Seismic Provisions. The probabilities of reaching various damage states are obtained by fragility analysis to evaluate the margin for safety against earthquakes, and the life cycle costs of the model structures are computed using the PACT (Performance Assessment Calculation Tool). According to the analysis results the slit-friction hybrid damper shows superior performance to the slit damper with the same yield strength for seismic retrofit of structures. The analysis results also show that the probabilities of reaching the limit states are minimized by the seismic retrofit with hybrid dampers combined with increasing column size. The combined seismic retrofit method also results in the lowest repair cost and shortest repair time.

Power frequency electromagnetic fields are the risk factor for occupational and general public health. International and national electromagnetic safety guidelines set the exposure limit values and have some significant differences. The goal of this paper is to compare Russian hygienic norms with ICNIRP guidelines, EU Directive requirements for 50 Hz electromagnetic fields occupational and general public exposure, analyze and demonstrate the principal differences. The protection from harmful human electromagnetic field effect is based on principles: protection by time, protection by distance and protection by protective equipment. Various hygienic regulations use different approaches to the human harmful effect definitions therefore there are distinctions of electromagnetic fields permissible limit values in International and national electromagnetic safety standards and guidelines. ICNIRP guidelines and Directive EU regard safety limits only from short-term, acute effect. Chronic electromagnetic field exposure harmful effect threshold is a basis for Russian hygienic norm. These thresholds are defined as a results of biomedical complex researches. Protection by time principle is realized in Russian hygienic norms, which are strong time dependent for occupational exposure. It is the main distinctive characteristics from International hygienic guidelines and is based on chronic exposure harmful human health effect threshold definition and electromagnetic field cumulative effects concept. Russian permissible limit value (25 kV/m) may be higher than ICNIRP (10 kV/m) and Directive EU (20 kV/m) levels, but is limited by working time (no more than 10 min per day). In Russia for general public permissible limit values are graded according to possible exposure time per day.