limit values
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2023 ◽  
Vol 83 ◽  
Author(s):  
A. Çavuş ◽  
F. Şen

Abstract Since water is one of the essentials for life, the presence and quality of water in the habitat is extremely important. Therefore, water quality change and management of Lake Aygır was investigated in this study. For this, water samples collected from the lake and the irrigation pool between May 2015 and May 2016 were analyzed monthly. Spectrophotometric, titrimetric and microbiological methods were used to determine the water quality. According to some water quality regulations, HCO3, NH4, Cu, Mo, Br, fecal coliform and total suspended solid (TSS) values were found above the limit values. The other 29 parameters comply with Turkish national and international legislations. Lake Aygır was negatively affected by the surrounding settlements and agricultural activities. It is thought that the water resource should be monitored periodically and remedial studies should be done to prevent parameters exceeding the limits. However, Lake Aygır was generally suitable for drinking, use, fishing and irrigation.


Forests ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 125
Author(s):  
Björn Berg ◽  
Mikael Lönn

We have reviewed information on early-, late- and limit-value decomposition stages for litter of Norway spruce (Picea abies) and Scots pine (Pinus silvestris). This synthesis covers c 16 studies/papers made along a climatic gradient; range in mean annual temperature (MAT) from −1 to +7 °C and mean annual precipitation (MAP) from 425 to 1070 mm. Scots pine has an early stage dominated by carbohydrate decomposition and a late stage dominated by decomposition of lignin; Norway spruce has just one stage dominated by lignin decomposition. We used data for annual mass loss to identify rate-regulating factors in both stages; climate data, namely, MAT and MAP, as well as substrate properties, namely, nitrogen (N), acid unhydrolyzable residue (AUR), manganese (Mn). Early-stage decomposition for Scots pine litter was dominated positively by MAT; the late stage was dominated negatively by MAT, N, and AUR, changing with decomposition stage; there was no effect of Mn. Norway spruce litter had no early stage; decomposition in the lignin-dominated stage was mainly negative to MAP, a negative relationship to AUR and non-significant relationships to N and MAT. Mn had a positive relationship. Limit values for decomposition, namely, the accumulated mass loss at which decomposition is calculated to be zero, were related positively to Mn and AUR for Scots pine litter and negatively to AUR for Norway spruce litter. With different sets of rate-regulating factors as well as different compounds/elements related to the limit values, the decomposition patterns or pathways are different.


Healthcare ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 160
Author(s):  
Daniel Fernández-Sanchis ◽  
Natalia Brandín-de la Cruz ◽  
Carolina Jiménez-Sánchez ◽  
Marina Gil-Calvo ◽  
Pablo Herrero ◽  
...  

Introduction: Dry needling is a non-pharmacological approach that has proven to be effective in different neurological conditions. Objective: The aim of this study was to evaluate the cost-effectiveness of a single dry needling session in patients with chronic stroke. Methods: A cost-effectiveness analysis was performed based on a randomized controlled clinical trial. The results obtained from the values of the EuroQol-5D questionnaire and the Modified Modified Ashworth Scale were processed in order to obtain the percentage of treatment responders and the quality-adjusted life years (QALYs) for each alternative. The cost analysis was that of the hospital, clinic, or health center, including the equipment and physiotherapist. The cost per respondent and the incremental cost-effectiveness ratio of each alternative were assessed. Results: Twenty-three patients with stroke were selected. The cost of DN treatment was EUR 14.96, and the data analysis showed a favorable cost-effectiveness ratio of both EUR/QALY and EUR/responder for IG, although the sensitivity analysis using limit values did not confirm the dominance (higher effectiveness with less cost) of the dry needling over the sham dry needling. Conclusions: Dry needling is an affordable alternative with good results in the cost-effectiveness analysis—both immediately, and after two weeks of treatment—compared to sham dry needling in persons with chronic stroke.


2022 ◽  
Vol 28 (5) ◽  
pp. 9-23
Author(s):  
O. M. Parkhomenko ◽  
V. O. Shumakov ◽  
T. V. Talayeva ◽  
I. V. Tretyak ◽  
O. V. Dovhan

The aim – to create a new method of assessing the development of long-term complications in STEMI patients by studying blood cell composition and its adaptation to practical application in general clinical practice.Materials and methods. The study was involved 148 patients with acute myocardial infarction (AMI) who was admitted from January 2014 to June 2020 to the intensive care unit. Some patients were evaluated retrospectively and were in group 1 (n=92). Group 2 – 56 patients, who were studied prospectively. The groups of patients did not differ in clinical and anamnestic characteristics and treatment. The study provided an annual observation period. The endpoint in group 1 was: death, stroke, exacerbation of coronary heart disease – including the need for revascularization, the developement or decompensation for heart failure, which led to hospitalization (in addition, group 2 was analyzed for onset of cardiac death).Results and discussion. There complex indicators were built, based on the analysis of the clinical profile and dynamics of laboratory parameters in patients with the onset of the endpoint – a modified leukocyte index (mLI), which contains the values ​​of the number and percentage of granulocytes, lymphocytes and monocytes on days 1, 3 and 10 of STEMI and leukocyte-platelet index (mLPI), which additionally includes indicators of platelet inhomogeneity in size (PDWc and P-LCR). These indices with their limit values ​​(mLI > 140 units and mLPI > 242 units) were more informative in predicting distant cardiovascular events than other laboratory markers (including neutrophil-leukocyte ratio, NLR). In a prospective study branch (group 2), the mLI and mLPI indicators also turned out to be more informative than other markers (in particular, the NLR indicator) in determining the propensity to occur as a combined endpoint (area under the curve 0.71 for both; p>0.0001), so and death (areas under the curve 0.78 and 0.84, respectively; p>0.0001). Based on the data obtained, a computer algorithm has been created that simplifies the risk assessment in AMI patients using the developed indicators.Conclusions. Created leukocyte and leukocyte-platelet indices are highly informative in predicting the risk of complications in patients within a year after AMI.


2022 ◽  
Vol 4 (6) ◽  
pp. 5-25
Author(s):  
A. Erykov

the group of deformed structures includes buildings that have received unacceptable subsidence and deformation during the period of their construction and especially operation, which, however, do not interfere with the perfor-mance of their main functions, but may eventually collapse. Their causes are errors in engineering and geological surveys and design; violation of the rules for performing construction work and operation of buildings and struc-tures. Long-term geodetic observations of the precipitation of the foundations of buildings on pile foundations have shown that both absolute and relative stabilized values of subsidence in the vast majority of cases are less than them and the normative limit values are calculated. Therefore, the group of deformed buildings on pile foun-dations includes somewhat less often similar objects with shallow foundations. The reasons for excessive subsid-ence of the foundations of pile foundations of buildings (and as a result, the occurrence and development of cracks and other deformations in load – bearing structures), in addition to these, are most often: unjustified use of increasing correction coefficients for the results of compression tests of highly acidic soils; the lower ends of the piles falling into layers of weak soil; the tip of the piles sinking from the design mark; overestimation of the bear-ing capacity of the piles due to non-compliance with the optimal time of their "rest" after immersion or erroneous interpretation of the graphs "load-pile sediment"; excessively close placement of neighboring piles in the plan, which when they are immersed, especially in the sand, leads to "pushing" up previously submerged; uneven load-ing of piles as part of the grillage; deformation of existing buildings and structures when driving piles near and tongue-and-groove, the development of pits, etc.


2022 ◽  
Vol 15 (4) ◽  
pp. 139-149
Author(s):  
F. G. A. Pereira ◽  
V. E. Botechia ◽  
D. J. Schiozer

Pre-salt reservoirs are among the most important discoveries in recent decades due to the large quantities of oil in them. However, high levels of uncertainties related to its large gas/CO2 production prompt a more complex gas/CO2 management, including the use of alternating water and gas/CO2 injection (WAG) as a recovery mechanism to increase oil recovery from the field. The purpose of this work is to develop a methodology to manage cycle sizes of the WAG/CO2, and analyze the impact of other variables related to the management of producing wells during the process. The methodology was applied to a benchmark synthetic reservoir model with pre-salt characteristics. We used five approaches to evaluate the optimum cycle size under study, also assessing the impact of the management of producing wells: (A) without closing producers due to gas-oil ratio (GOR) limit; (B) GOR limit fixed at a fixed value (1600 m³/m³) for all wells; (C) GOR limit optimized per well; (D) joint optimization between GOR limit values of producers and WAG cycles; and (E) optimization of the cycle size per injector well with an optimized GOR limit. The results showed that the optimum cycle size depends on the management of the producers. Leaving all production wells open until the end of the field's life (without closing based on the GOR limit) or controlling the wells in a more restricted manner (with closing based on the GOR limit), led to significant variation of the results (optimal size of the WAG/CO2 cycles). Our study, therefore, demonstrates that the optimum cycle size depends on other control variables and can change significantly due to these variables. This work presents a study that aimed to manage the WAG-CO2 injection cycle size by optimizing the life cycle control variables to obtain better economic performance within the premises already established, such as the total reinjection of gas/CO2 produced, also analyzing the impact of other variables (management of producing wells) along with the WAG-CO2 cycles.


2022 ◽  
Vol 961 (1) ◽  
pp. 012068
Author(s):  
Rawaa Al-Isawi ◽  
Intidhar Jabir Idan ◽  
Afrah Abood Hassan

Abstract Acoustic conditions, considered an indicator of the level of comfort, are a major concern in educational facilities since they are linked to students’ well-being and learning capacity. In this study, measurements of the acoustical comfort conditions were performed using portable IEQ meter have been assessed in four selected areas of environmental engineering department building (The classroom for fourth year, student’s corridor, teacher’s corridor and reception area) in the University of Babylon in Hillah City. This was done by analyzing the data measured for 13 months from August (2020) to August (2021). Statistical analysis by using the linear regression test was performed to determine the relationship between the selected areas. Noise is the major parameter for the educational areas that can interfere with the students’ activities and eventually, this will have a detrimental effect on the students’ physical and psychological health. The acquired results were compared to the reference values specified in the handbook to international standards for noise compliance in academic educational facilities. The results show that all the studied areas in the Environmental Engineering Department had back-ground noise levels out of the recommended threshold limit values (>50 dB) revealed that the indoor environment of these areas was of poor quality, indicating the require for interventions. This study can be considered a pilot study for future comparable research on Iraqi universities.


2022 ◽  
Author(s):  
Angelo Robotto ◽  
Secondo Barbero ◽  
Roberto Cremonini ◽  
Enrico Brizio

A better air quality has led to a significant reduction of premature deaths over the past decade in Europe, as emissions of many pollutants declined considerably in the EU-27 Member States: SOx emissions by 76%, NOx by 42%, NMVOCs by 29% and PM2.5 by 29%. The present paper reports an in-depth analysis of the reasons why the regions of the Po valley, Northern Italy, still have difficulties to comply with EU air quality standards, in particular for PM10 and NO2, in spite of strong emission reductions carried out through careful Air Quality Plans put in practice during the last 2 decades. The analysis includes a consistent comparison of emission inventories for different European regions in Italy, Germany and Poland, the measured air quality trends and PM source apportionment in these areas, and, most of all, a thorough investigation of meteorological parameters influencing atmospheric pollutant dispersion and transport. The study reports that in the colder seasons, wind speed, PBL height and atmospheric pressure occurring in the Po basin are three to five times less efficient in diluting and dispersing pollutant if compared to regions north of the Alps. Due to the extremely disadvantageous orographic and climatic configuration of the Po Valley, only radical emission reductions could bring air quality into EU limit values with a questionable cost-benefit ratio of due policies. Provided that air quality standards (particularly for PM10 and PM2.5) aim at protecting people from adverse health effects arising from air pollution, it is however necessary to also consider the toxicity of atmospheric particulate in addition to PM10/PM2.5 mass concentration as a limit value. Based on existing toxicological studies and reports, a discussion is reported about PM toxicity factor depending on toxicity scores for source-specific aerosols and PM composition determined by Source Apportionment. Provided that PM components profiles are strongly different across Europe, the obtained PM toxicity factors range from 0.3 (for areas where the main PM contribution is referable to sea salts or inorganic matter) to 3.5 (where Elemental and Organic Carbon prevail), suggesting that, even at the same mass concentration, the effects of PM10/2.5 on human health are significantly variable and limit values should take into account differential toxicity. Modern PM Source Apportionment techniques, along with reliable toxicity and epidemiological analyses, represent the right tools to overcome the shortcomings of the current regulation standard and build a new consistent health metric for ambient PM in the future, helping policy makers impose effective air quality measures to protect people health.


Author(s):  
Jiansheng Tong ◽  
Zhengyuan Lin ◽  
Qian Zhou

In order to minimize the self-weight and prevent local buckling failure of thin-walled box concrete arch bridges at the same time, the limit values of width-thickness ratios are deduced based on Ritz method and equivalent strut theory of arch bridge. A new method of determining sectional forms based on the limit values of width-thickness ratios is put forward. Based on Mupeng bridge, the theoretical results are verified by finite element software ANSYS. Results show that the limits of width-thickness ratios are related to concrete grade, equivalent calculation length and radius of gyration, the allowable minimum thickness of Mupeng bridge is 15 cm to avoid local buckling. The limit values of width-thickness ratios deduced in this paper are reasonable and this new method of determining sectional forms is simple and rational to apply in engineering. A scientific engineering calculation method on arch ring design is put forward and it can provide a theoretical basis for the design of thin-walled box concrete arch bridges constructed by cantilever pouring.


Author(s):  
K. Ulutaş ◽  
S. K. M. Abujayyab ◽  
İ. R. Karaş

Abstract. In this study, PM10 values from the air quality monitoring station in Izmir was evaluated. 9 stations could be used in this study, since PM10 data are suitable to evaluate for the years 2020-2019-2018. The 4-season and annual PM10 distribution map for 3 years was prepared using ArcGIS. The benefits of these maps to city managers in the smart city application were expressed. In addition, PM10 data of 9 stations were evaluated according to legal limit values. It was determined that Aliağa and Gaziemir stations exceeded the limit values more than other stations. It has been observed that different sources of air pollution such as industry, traffic and heating affect different districts. When the number of days exceeding the limit value and the number of days without measurement are evaluated together, it is seen that the limit values are exceeded by all stations.


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