scholarly journals Study on the Oxygen Enrichment Effect of Individual Oxygen-Supply Device in a Tunnel of Plateau Mine

2020 ◽  
Vol 17 (16) ◽  
pp. 5934
Author(s):  
Zijun Li ◽  
Rongrong Li ◽  
Yu Xu ◽  
Yuanyuan Xu
Keyword(s):  
Exponential Function ◽  
Mass Fraction ◽  
Oxygen Supply ◽  
Oxygen Enrichment ◽  
Low Oxygen ◽  
Range Analysis ◽  
Airflow Velocity ◽  
Positive Correlation ◽  
The Individual ◽  
Supply Velocity

Complex characteristics of the plateau environment such as low oxygen content seriously restrict the exploitation of abundant mineral resources in plateau areas. To regulate the hypoxia environment and improve the comfort of workers engaged in intense physical labor like tunnel excavation operations in plateau mines, an individual oxygen-supply device for tunnel of plateau mine was proposed to create local oxygen enrichment in the area around the human nose. The Computational Fluid Dynamics (CFD) method was used to judge the application’s effect of the individual oxygen-supply device in plateau mine, revealing the oxygen diffusion law under the influence of different oxygen enrichment factors. The orthogonal design and range analysis were used to measure the degree of influence of major factors such as oxygen-supply velocity, oxygen-supply concentration, and tunnel airflow velocity. The results demonstrate that the oxygen mass fraction of the air inhaled by the human had a positive correlation exponential function, a positive correlation linear function, and a negative correlation exponential function, respectively, concerning oxygen-supply velocity, oxygen-supply concentration, and tunnel airflow velocity. The range analysis revealed that the major influencing factors of oxygen enrichment in the tunnel of the plateau mine were, in a descending sequence, as follows: oxygen-supply concentration, tunnel airflow velocity, and oxygen-supply velocity, and the corresponding ranges were 2.86, 2.63, and 1.83, respectively. The individual oxygen-supply device achieved the best oxygen enrichment effect when the oxygen-supply velocity was 5 m/s, the oxygen-supply concentration was 60%, and the tunnel airflow velocity was 0.2 m/s, which increased the oxygen mass fraction of air inhaled by the human to 30.42%. This study has a positive guiding significance for the improvement of the respiration environment in the tunnel of plateau mine.

scholarly journals Speciation of organosulfur compounds in carbonaceous chondrites

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alexander Zherebker ◽  
Yury Kostyukevich ◽  
Dmitry S. Volkov ◽  
Ratibor G. Chumakov ◽  
Lukas Friederici ◽  
...  
Keyword(s):  
Organic Matter ◽  
Analytical Techniques ◽  
Ion Cyclotron Resonance ◽  
Organosulfur Compounds ◽  
Low Oxygen ◽  
Fticr Ms ◽  
Insoluble Organic Matter ◽  
Composition And Structure ◽  
Extractable Fraction ◽  
The Individual

AbstractDespite broad application of different analytical techniques for studies on organic matter of chondrite meteorites, information about composition and structure of individual compounds is still very limited due to extreme molecular diversity of extraterrestrial organic matter. Here we present the first application of isotopic exchange assisted Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) for analysis of alkali extractable fraction of insoluble organic matter (IOM) of the Murchison and Allende meteorites. This allowed us to determine the individual S-containing ions with different types of sulfur atoms in IOM. Thiols, thiophenes, sulfoxides, sulfonyls and sulfonates were identified in both samples but with different proportions, which contribution corroborated with the hydrothermal and thermal history of the meteorites. The results were supported by XPS and thermogravimetric analysis coupled to FTICR MS. The latter was applied for the first time for analysis of chondritic IOM. To emphasize the peculiar extraterrestrial origin of IOM we have compared it with coal kerogen, which is characterized by the comparable complexity of molecular composition but its aromatic nature and low oxygen content can be ascribed almost exclusively to degradation of biomacromolecules.

scholarly journals The Hypoxic Testicle: Physiology and Pathophysiology

2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
Juan G. Reyes ◽  
Jorge G. Farias ◽  
Sebastián Henríquez-Olavarrieta ◽  
Eva Madrid ◽  
Mario Parraga ◽  
...  
Keyword(s):  
Germ Cell ◽  
Testicular Torsion ◽  
Oxygen Supply ◽  
Cell Function ◽  
Cell Damage ◽  
The Body ◽  
Body Core Temperature ◽  
Seminiferous Tubules ◽  
Low Oxygen ◽  
Complex Biological Process

Mammalian spermatogenesis is a complex biological process occurring in the seminiferous tubules in the testis. This process represents a delicate balance between cell proliferation, differentiation, and apoptosis. In most mammals, the testicles are kept in the scrotum 2 to 7°C below body core temperature, and the spermatogenic process proceeds with a blood and oxygen supply that is fairly independent of changes in other vascular beds in the body. Despite this apparently well-controlled local environment, pathologies such as varicocele or testicular torsion and environmental exposure to low oxygen (hypoxia) can result in changes in blood flow, nutrients, and oxygen supply along with an increased local temperature that may induce adverse effects on Leydig cell function and spermatogenesis. These conditions may lead to male subfertility or infertility. Our literature analyses and our own results suggest that conditions such as germ cell apoptosis and DNA damage are common features in hypoxia and varicocele and testicular torsion. Furthermore, oxidative damage seems to be present in these conditions during the initiation stages of germ cell damage and apoptosis. Other mechanisms like membrane-bound metalloproteinases and phospholipase A2 activation could also be part of the pathophysiological consequences of testicular hypoxia.

scholarly journals RESULTS OF TESTING OF MODERN INDIVIDUAL MILKING INSTALLATION

2021 ◽  
Author(s):  
O. Kryshtal ◽  
Keyword(s):  
Technological Process ◽  
Mass Fraction ◽  
Total Duration ◽  
Small Diameter ◽  
First Grade ◽  
Vacuum Pump ◽  
Average Intensity ◽  
Milking Machine ◽  
The Individual

The purpose of the research: comprehensive assessment of the individual milking unit of the company "Kurtsan" (Turkey) during operation. Methods of research: Analysis of the structural features of the individual milking unit performed by the observation method given to test sample, the quality of the machine was evaluated by standardized methods: the quality of the technological process and operational-technological indicators in accordance with the SOU 74.3-37-273, energy indices according to DSTU 2331, economic Indicators according to DSTU 4397, safety indicators and ergonomics according to DSTU IEES 60335-1, DSTU EN 60335-2-70. Research Results: The conducted research confirms a sufficiently high quality of the technological process of selection of milk in cows in the conditions of use of milking installation in a personal economy, which provides favorable conditions for the milking of the cow, taking into account its physiological features. Performance per hour of basic time is 10 heads. Milking installation works on the principle of a closed milking system, thanks to which milk does not contact the environment and immediately from the basin enters a sealed can. Such system protects milk from the possibility of bacterial and physical contamination. Milk obtained during milking by milking installation according to quality indicators (acidity, density, content of somatic cells, mass fraction of dry matter, mass fraction of fat) meets the requirements for the first grade according to DSTU 3662. Milking installation is equipped with a dry vacuum pump. Power consumption during installation does not exceed 0.54 kW. Specific electricity consumption for milking of one cow is 0.05 kWh / head. Annual operating expenses for milking of two cows in the farm are 1591.90 UAH / head. Conclusions. According to the testing of the individual milking plant manufacturing company "KURTSAN", it has been established that this installation reliably performs the technological process of machine milking of cows in milking can for their tethered maintenance and allows you to get milk of the first grade. The total duration of visiting one cow is 5.75 minutes. The average intensity of milk is 1.0 kg / min. Milking machine provides complete bodies of cows. The magnitude of the control manual feed is 50 ml. The milking machine is equipped with an adjustable pulsator of pairwise milking, which creates a manual milking process and works for a working vacuum of 40 ± 1 kPa, which prevents injury to dies and diseases of mastitis. In the cover the "Stop-Milk" system is installed, which prevents milk from entering a vacuum pump during the overflow of the poor, or water while washing All items are compactly assembled on a single cart. However, a small diameter of wheels on an unequal surface creates some inconvenience to the operator during the transportation of the machine with a filled milk capacity. The application of the installation increases the amount of milk received. Its gentle work does not harm the emotional and physical health of the cow: the dysfunctions during operation are not pushed, and light vibration creates a massage effect. Milking installation allows you to significantly reduce the labor of service personnel in an economy with a maintenance of 1 to 10 cows.

scholarly journals Standardization and Validation of the Personality Disorder Inventory PSGP-IPDI

2019 ◽  
Vol 7 (1) ◽  
pp. 112-122
Author(s):  
K Abilash ◽  
P Sindhuja Manisha Kamini ◽  
T Jothimani
Keyword(s):  
Personality Disorder ◽  
Psychiatric Disorder ◽  
Internal Consistency ◽  
Psychiatric Patients ◽  
Personality Inventory ◽  
Clinical Population ◽  
Positive Correlation ◽  
Characteristic Behavior ◽  
The Individual ◽  
The Relationship

Background: Personality is the dynamic organization within the individual of those psychophysical systems that determine characteristic behavior and thought. Aim: To standardize and validate personality disorder inventory in clinical population. Methods and Samples: 100 Psychiatric patients were taken as a sample as a clinical population in various hospital Coimbatore age ranged 28 – 58. PSGP- IPDI- Indian Personality Disorder Inventory assessed for 100 psychiatric disorder individuals. Results: The relationship among the disorders of the personality inventory shows both positive and negative correlations among the dimensions most of the dimensions exhibited positive correlation. The internal consistency of the inventory is reliable.Conclusion: The personality disorder inventory is reliable and significant and this tool can be administered on the clinical population.

Ventilation improvement for reducing individual exposure to cooking-generated particles in Chinese residential kitchen

2016 ◽  
Vol 26 (2) ◽  
pp. 226-237 ◽  
Author(s):  
Changsheng Cao ◽  
Jun Gao ◽  
Li Wu ◽  
Xihui Ding ◽  
Xu Zhang
Keyword(s):  
Airborne Particles ◽  
Exposure Level ◽  
Individual Exposure ◽  
Air Supply ◽  
Cooking Process ◽  
Baseline Case ◽  
Open Window ◽  
The Individual ◽  
Supply Mode ◽  
Supply Velocity

This paper investigates the situation of residential kitchen ventilation and individual exposure in China and attempts to reduce the exposure through organizing local make-up airflow. Measurements were conducted in a kitchen chamber to reproduce the real exposure to the cooking-generated particles under the mode of natural make-up airflow surveyed. Measurements results show that an individual cooking in a kitchen could be exposed to a concentration of airborne particles at ∼10 mg/m3 within a simplified cooking process of oil heating, in the case of an experimental kitchen chamber with an open window or closed window/door. Local make-up airflow through upward make-up air supply or downward make-up air supply was further investigated to determine the effectiveness for reduction of the exposure level. When the air-supply velocity at the outlet of the upward make-up air supply or downward make-up air supply mode was well defined, the individual exposure level could be reduced by 2–3 orders of magnitude, as compared to the baseline case when all the make-up air was from open window. Intake fraction of cooking-generated particles could be as low as ∼10−5 and ∼10−6 under the two modes. This finding has illustrated that well-organized local make-up airflow could largely reduce an individual’s exposure to the cooking-generated particles in Chinese residential kitchen.

Patterns in the distribution of Melanesian land Mollusca

1969 ◽  
Vol 255 (800) ◽  
pp. 285-306 ◽  
Keyword(s):  
Pacific Region ◽  
Ecological Diversity ◽  
Positive Correlation ◽  
The Pacific ◽  
Distributional Patterns ◽  
Changing Patterns ◽  
Biological Attributes ◽  
The Individual ◽  
Taxonomic Groups ◽  
Available Information

Melanesia is important in any discussion concerned with the distribution of terrestrial Mollusca in the Pacific region, as a zone exhibiting an intermingling of faunas derived from different geographical areas. Along the chain of islands constituting Melanesia these faunal elements exhibit changing patterns consistent with island hopping across water gaps. Yet the numbers of species of Mollusca on these islands show a positive correlation with the size of the individual islands (figure 19) and not, as might be expected, with the distance of particular taxonomic groups from centres of dispersal. Variations in this pattern can be attributed to differences in the isolation of islands, ecological diversity and the paucity of collecting in many areas. It should be realized that the distributional patterns recorded for any particular taxon must reflect the frequency and density of collecting and the inadequacies of the systematics of the group, besides biological attributes of the taxon and the island. The limitations should not distract, however, from attempts to analyse the available information, instead they must serve as a guide to the difficulties involved.

The effects of oxygen and medicines on T cells in hypoxic co-culture

2021 ◽  
Keyword(s):  
T Cells ◽  
Cell Viability ◽  
Oxygen Supply ◽  
Interleukin 2 ◽  
Hypoxic Condition ◽  
Severe Trauma ◽  
Multiple Organ ◽  
Trauma Patients ◽  
Low Oxygen ◽  
Western Blots

Objectives: Many patients with massive hemorrhage, respiratory failure due to trauma admit the emergency department, and further that the experience can fall into shock, inducing to sepsis, multiple organ failure due to hyperinflammation or immunosuppression. In the these patients, the low oxygen flow with immunosuppression is believed to play a significant role. Hence, oxygen supply and medicines is essential in severe trauma patients. Therefore, this study aims to investigate the effects of oxygen and variable medicines in hypoxic condition. Methods: T cells and macrophages were plated into trans-well plate for co-culture for 30 minutes in hypoxia. After that, the cells were stimulated with lipopolysaccharide (LPS) followed by variable medicines by normoxia or oxygen supply for 2 hrs and cells were inculated overnight under normoxic conditions. The T cell viability was measured by MTT, and the expression of interleukin-2 (IL-2), interleukin-8 (IL-8) and macrophage migration inhibitory factor (MIF) were measured by western blots using the T cells with co-culture with inflammatory maccrophages. Also, the concentration of MIF was analyzed by ELISA. Results: The T cells viability was decreased in hypoxia with LPS stimulation, however, pentoxifylline (PTX) effectively restored cell viability regardless of oxygen state (p < 0.05). Besides, PTX in oxygen supply status restored the decreases in IL-2 expression of T cells and the increases MIF in the LPS stimulation with hypoxia (p < 0.05). Conclusions: PTX has more effectively restored the T cells immunosuppression in hypoxia during oxygen supply, and has an immunomodulation effect by controlling hyperinflammation.

Testosterone precursors in spermatic venous blood of normal men and varicocele patients

1985 ◽  
Vol 108 (2) ◽  
pp. 277-283 ◽  
Author(s):  
S. Andò ◽  
C. Giacchetto ◽  
G. M. Colpi ◽  
E. Beraldi ◽  
M. L. Panno ◽  
...  
Keyword(s):  
Negative Correlation ◽  
Venous Blood ◽  
Normal Subjects ◽  
Hydroxylase Activity ◽  
Positive Correlation ◽  
Testosterone Biosynthesis ◽  
The Mean ◽  
The Individual ◽  
Normal Men

Abstract. In the present study we determined progesterone (p), 17-OH-progesterone (17-OH-P), androstenedione (Δ4), dehydroepiandrosterone (DHEA) and testosterone (T) in spermatic venous blood of 34 varicocele patients and of 13 normal subjects. We also used the DHEA/Δ4 ratio as an index of the Δ5/Δ4 pathway ratio in testosterone biosynthesis. The mean of T and Δ4 in the spermatic blood of varicocele (V) patients appeared to be significantly lower with respect to that of normal (N) subjects (T:N = 1718.2 ± 202.4 (sem) nmol/l, No. 11; V = 1243.7 ± 97 (sem) nmol/l, No. 34; P < 0.03. Δ4: N = 56.4 ± 5.6 (sem) nmol/l, No. 12; V = 38.1 ± 4 (sem) nmol/l, No. 27, 0.02> P>0.01). A negative correlation was observed between the individual age of varicocele patients and 17-OH-P (No. 34, y = −30.66x + 1300, r = −0.57, P < 0.01) Δ4 values (No. 27, y = −1.981x + 96.52, r = −0.67, P< 0.01). When the ratio of T precursors was evaluated, we observed a positive correlation between the P/17-OH-P ratio and age of varicocele (No. 33, y = 0.0065x–0.092, r = 0.45, P < 0.03). The 17-OH-P/Δ4 ratio was greatly increased with respect to that of normal subjects (N = 5.12 ± (sem), No. 12; V= 10.77 ± 1.31 (sem), No. 27; P<0.01). These data suggest that the reduced T levels in spermatic venous blood of varicocele patients were due firstly to the enzymatic deficiency of 17-20-lyase and secondly to that of 17α-hydroxylase activity as the patients grow relatively older. The negative correlation between the DHEA/Δ4 ratio and Δ4/T ratio was observed in normal subjects (No. 10, y = −0.00432x + 0.0542, r = −0.67, P < 0.03) as well as in varicocele patients (No. 27, y = −0.00399x + 0.0587, r = −0.48, 0.02 > P > 0.01). This indicates that in the testis of varicocele patients the testosterone remains prevalently supplied by the Δ5 pathway of biosynthesis.

scholarly journals ANCAMAN HIPOKSIA BAGI EKOSISTEM PESISIR; PENGGUNAAN INDEKS AMMONIA-ELPHIDIUM (A-E) SEBAGAI PROKSI

OSEANA ◽  
2020 ◽  
Vol 45 (1) ◽  
pp. 82-92
Author(s):  
Ricky Rositasari
Keyword(s):  
Retrospective Study ◽  
Coastal Waters ◽  
Aquatic Ecosystems ◽  
Oxygen Supply ◽  
Double Effect ◽  
Anthropogenic Factors ◽  
Low Oxygen ◽  
Hypoxic Conditions ◽  
Preliminary Information ◽  
The World

Hypoxia is one of the aquatic phenomena caused by natural and/or anthropogenic factors. Eutrophication is the main trigger of hypoxia in coastal waters throughout the hemisphere. Hypoxia that occurs in aquatic ecosystems refers to the low concentration of dissolved oxygen in the water column to less than 2 mg/L. Hypoxia causes a double effect, low oxygen supply for biotic physiological process, and triggers ocean acidification. Prolonged hypoxic conditions will have a significant impact on the food webs in coastal waters and sea waters, further conditions will ultimately have an impact on capture-based fishing activities. The case of hypoxia in Indonesian coastal waters has not been widely revealed and has not been a concern to be understood or traced to its existence. Retrospective as well as actual traces of hypoxia were revealed, especially in the waters of Jakarta Bay. The retrospective study was carried out using proxies that have been used in various tropical and subtropical countries, the Ammonia-Elphidium (A-E) index (Foraminifera). The results show that several places in the coastal waters of Jakarta Bay and Semarang have experienced episodic hypoxic events for several centuries. A brief review of phenomenal hypoxic events in other parts of the world and preliminary information on recorded events in several Indonesian coastal waters are expected to open stakeholder awareness about further threats of hypoxia in Indonesian waters.

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