Main Cause Of Decrease Research Articles

Spectral investigation of lithium-telluride based glasses doped with Sm3+-ions for lighting application

Glasses with compositions TeO2-BaO-Li2O-GeO2:Sm2O3 were prepared by melt-quenching technique and labeled by TBaLG-Sm. In this study, we report their radiative, physical, optical and luminescence properties. In the emission spectra, four emission peaks were observed at 563 nm, 599 nm, 645 nm, 707 nm wavelengths with corresponding transitions as 4G5/2→6H5/2, 4G5/2→6H7/2, 4G5/2→6H9/2 and 4G5/2→6H11/2, respectively. Up to 1.0 mol% of Sm3+-ion concentration the emission intensity increases, followed by decreasing with further increasing Sm3+-ion content. A non-radiative energy transfer via cross-relaxation channels between Sm-Sm ions is the main cause of decrease in emission intensity. Computing from the absorption and emission spectra, the Judd-Ofelt parameters, radiation transition probability, spectroscopic quality factors and emission cross section were evaluated. The color coordinates of all samples lie in the orange region of the Commission International de lˊEclairage diagram. The large values of branching ratios and stimulated emission cross-section reveal that the studied glass con be used as a lasing material and a lighting device.

Математична модель оптимізації технологічного розвитку нафтогазової галузі

The main causes for decrease in the hydrocarbons production in Ukraine are the transition of most fields, giving their major production and having major reserves, to the late stage of development, which is characterized by significant depletion (80–85% of the initial reserves), and the results of exploration work give mainly very small, small, and medium deposits at considerable depths of 4.5–6 km. Under these conditions, it is urgent to solve the problem of forecasting the development of fuel industries by developing economic and mathematical models of prediction of the processes of diffusion of efficient technologies in the oil and gas industries of country's power complex. For the first time in Ukraine, we constructed a mathematical model of the time dependence of volume of hydrocarbon production during a limited period of the development of a field. We used here binary variables to determine the critical points of such dependence, which enables one to consider the problem of optimal planning of the discovery and development of oil and natural gas fields. Furthermore, we created a model of the optimization of development of the mining industry with a cost criterion to determine the expedient time of commissioning of deposits with preassigned indicators of the time dependence of production volume. On this basis, the L.V. Kantorovich model was constructed, which, in the assortment vector, binds mining volumes with production volumes of hydrocarbon reserves, whose increase is a prerequisite for the enhancement of production in the country. Using the described models, we performed test calculations for three types (small, medium, large) of new fields, the development of which should satisfy the production volumes by the stages of period of modeling of the industry development. In order to ensure the forecasted total production volumes, it is necessary to start commissioning both small and medium-size deposits at the initial stages of development of the industry, which requires considerable investment in prospecting and exploration.

Retinal Phenotype in the rd9 Mutant Mouse, a Model of X-Linked RP.

Retinal degeneration 9 (rd9) mice carry a mutation in the retina specific “Retinitis Pigmentosa GTPase Regulator (RPGR)” Open Reading Frame (ORF) 15 gene, located on the X chromosome and represent a rare model of X-linked Retinitis Pigmentosa (XLRP), a common and severe form of retinal degeneration (Wright et al., 2010; Tsang and Sharma, 2018). The rd9 RPGR-ORF15 mutation in mice causes lack of the protein in photoreceptors and a slow degeneration of these cells with consequent decrease in Outer Nuclear Layer (ONL) thickness and amplitude of ERG responses, as previously described (Thompson et al., 2012). However, relative rates of rod and cone photoreceptor loss, as well as secondary alterations occurring in neuronal and non-neuronal retinal cell types of rd9 mutants remain to be assessed. Aim of this study is to extend phenotype analysis of the rd9 mouse retina focusing on changes occurring in cells directly interacting with photoreceptors. To this purpose, first we estimated rod and cone survival and its degree of intraretinal variation over time; then, we studied the morphology of horizontal and bipolar cells and of the retinal pigment epithelium (RPE), extending our observations to glial cell reactivity. We found that in rd9 retinas rod (but not cone) death is the main cause of decrease in ONL thickness and that degeneration shows a high degree of intraretinal variation. Rod loss drives remodeling in the outer retina, with sprouting of second-order neurons of the rod-pathway and relative sparing of cone pathway elements. Remarkably, despite cone survival, functional defects can be clearly detected in ERG recordings in both scotopic and photopic conditions. Moderate levels of Muller cells and microglial reactivity are sided by striking attenuation of staining for RPE tight junctions, suggesting altered integrity of the outer Blood Retina Barrier (BRB). Because of many features resembling slowly progressing photoreceptor degeneration paradigms or early stages of more aggressive forms of RP, the rd9 mouse model can be considered a rare and useful tool to investigate retinal changes associated to a process of photoreceptor death sustained throughout life and to reveal disease biomarkers (e.g., BRB alterations) of human XLRP.

The Effect of Globalization and Modernisation on Selling Power Decrease of Toys Street-Seller in the City

This research studies several toys street-seller in the city, whose data is obtained through electronic paper media. This research has a purpose to describe how globalization and modernisation contribute to the decrease of appeal towards toys, which are sold in the street. The method used in this research is qualitative method. The theory used is the theory of William Ogburn concerning the culture barrier and subject of modernisation. The result of this research shows that the main cause of decrease of appeal towards toys street-seller is due to dispersion of mobile games because of globalization and modernisation, besides the intricate regulations on toys standard which caused the high price tag on toys which are sold on the street, that resulted in the proliferation of mobile games.

Fish diversity of Haryana and its conservation status

The present study on fish biodiversity of Haryana state was carried out during 2011 to 2014. A total number of 59 fish species inhabits the freshwaters of this state. Maximum number of fish species belonged to the order Cypriniformes (35) followed by the order Siluriformes (12) and Perciformes (8). The orders Beloniformes,Clupeiformes, Osteoglossiformes and Synbranchiformes were represented by only one species each. Out of 59 fish species, 2 are endangered, 11 vulnerable, 28 have lower risk of threat, 8 exotic and 4 fish species have lower risk least concern. The conservation status of six fish species has not been evaluated so far, hence they cannot be included in any of the IUCN categories at this moment. Family Cyprinidae alone contributed 32 fish species followed by Bagridae family. Fish species Parapsilorhynchus discophorus was observed for the first time in Haryana waters. This species is the native of Kaveri river basin, the occurrence of this species in river Yamuna may be attributed to some religious activity of people. A decline in fish diversity has been recorded from 82 species in 2004 to 59 species in the present study in the year 2014. The main causes for decrease in fish biodiversity are habitat destruction and fragmentation, changing practices of land use, exotic species introduction, fishing, irrigation needs, pollution and global climate change impacts. It is essential to prevent further decline of fish resources by devising all possible measures of conservation and rehabilitation.

What caused the decrease in RevPAR during the recession?

Purpose – This study aims to attempt to examine whether the increase in hotel room capacity in the USA had a significant impact on nationwide aggregated weekly revenue per available room (RevPAR) during the recession of 2007-2009 and forecast average RevPAR, Occupancy and Average Daily Rate (ADR) for 2013 and 2014. Design/methodology/approach – Using Autoregressive Integrated Moving Average with Intervention analysis technique, this study examined the significance of the fluctuations in weekly RevPAR, room capacity and market demand through the recent recession and forecasted hotel performance for 2013 and 2014. Findings – The results of time series analysis suggest that the fast growth of room capacity during the recession was one of the main causes of the decrease in RevPAR. The 9,878 more than expected increase in average weekly number of rooms probably caused at least $0.10 more than expected decrease in average weekly RevPAR. The findings of this study also suggest that the US lodging industry has been facing more severe oversupply since the recession and fully rebound of RevPAR cannot be expected in the very near future. Practical implications – The findings of this study will help stakeholders make more informed decisions to cope with possible future economic downturns. By quantifying the capacity increase and forecasting future market demand, this study provides hotel investors with empirical evidence on the overdevelopment and insights into expected overall hotel performance in next two years. This study has also discussed the cyclical patterns of hotel development during the past two recessions. Originality/value – By identifying overdevelopment as one of the main causes of RevPAR decrease during the recession, this study contributes to the literature by adding an alternative explanation of RevPAR fluctuations and deepens the understanding of the adverse effects overdevelopment has on the lodging industry. The findings of this study will help hotel investors develop more informed future expansion plans.

Effect of standardized exercise program on reported fatigue in patients of cancer receiving chemotherapy

Context: Fatigue is an important symptom of cancer as well as a major side-effect of chemotherapy and is one of the main causes of decrease in physical performance brought on by the disease and its treatment. Several researches have been conducted to study the effect of exercise on relieving cancer related fatigue (CRF). This study will look into the effectiveness of exercise in reducing fatigue in patients of cancer undergoing chemotherapy. Aims: The aim was to study effect of a standard exercise program on fatigue in cancer patients on chemotherapy. Settings and Design: This was a case-control study conducted in a rural hospital setting. Materials and Methods: The case group was given an exercise intervention for 15 days and the control group was not given any intervention. The fatigue scores of both groups were assessed with the help of a Fatigue Severity Scale questionnaire 3 times during this time and compared. Statistical Analysis Used : An independent samples t-test was done to compare fatigue scores. Results: Fatigue scores collected from case and control group on the 15 th day showed statistical significance (t = 3.40 and P = 0.002). Conclusions: The study suggested that exercise was an effective intervention is reducing CRF in cancer patients undergoing chemotherapy. Further research is required to establish the type and duration of exercise that can provide optimum relief and alleviate the effects produced by CRF.

Diurnal temperature range variation and its causes in a semiarid region from 1957 to 2006

ABSTRACTThe diurnal temperature range (DTR) is an important indicator of climate change, and it has decreased worldwide since the 1950s, particularly over arid and semiarid regions. This study analyses the effect of meteorological and anthropogenic factors on DTR variation to investigate the possible causes of DTR decreases in semiarid climates. The study region is located in northeast China, and the study period is from 1957 to 2006. There are three main results. First, the rate of decrease in the DTR is −1.24 K per 50 years. This decrease is mainly attributed to the increasing daily minimum temperature rate (Tmin, 2.24 K per 50 years), which is greater than the change in the daily maximum temperature (Tmax, 1.00 K per 50 years). Second, sunshine duration (SD) appears to be the most significant meteorological factor that determines the DTR through downward shortwave radiation (Rsw,d) and surface soil moisture (SM). The effect of Rsw,d is larger for Tmax than for Tmin; therefore, the decrease in Rsw,d results in a smaller increase in Tmax than in Tmin. On the other hand, the increase in SM can strengthen daytime latent heat release, and the increase in Tmax is then slowed because of the cooling effect of evaporation. The precipitation values and the leaf area index show a negative correlation with the DTR, whereas the cloud amount and the relative humidity appear not to be main causes of the DTR decrease in this region. Finally, atmospheric aerosols can reduce the SD by 0.27 h year–1 by decreasing atmospheric transparency, as indicated by an analysis of the Total Ozone Mapping Spectrometer Aerosol Index from 1979 to 2005. The decrease in direct solar radiation is the main cause of decreases in Rsw,d. These findings will provide references for DTR variation studies in similar climates.

Evaluating the Effects of Climate Changes and LUCC on the Hydrological Processes Using Soil and Water Assessment Tool Models in Wangkuai Reservoir Watershed in China

Comprehensive management of lake water's quality and quantity from river eco-hydrological aspect has become an increased concern in terms of lake water ecology and environment; Baiyandian is the biggest natural lake and an important eco-function area in North China. However, due to the sharp decrease of water quantity from upstream basin, ecological and environmental problems have occurred in this lake, including frequent drying up, water pollution, and the extinction of valuable species. In this study, a small catchment the Wangkuai reservoir watershed which is located in the upstream Baiyangdian was selected as the research area. Using 3S topography and land use data as inputs for a distributed hydrological process model (SWAT), we simulated the water cycle process in Wangkuai reservoir based on changes in climate and land use-land. We elementarily analyzed the main cause of the sharp decrease of water flow in the small watershed Wangkuai Reservoir. The results of the research showed that, in the 50 years between 1958 and 2007, the ten-year average runoff decreased by 75.04%; from 1985 to 2007, warming and drying climate trend decreased the average annual runoff by 64.22%; from 1985 to 2007, the area of wood land in this watershed decreased by 13.27%, grass land and farmland increased by 4.89% and 26.15%, respectively; the contribution rate of climate changes and land use-land cover changes to the decrease of runoff were about 60% and 40%, from which we could see that climate change was the main cause of the decrease of runoff. This research could provide reference for water resource management and water environment protection of Wangkuai Reservoir.

Response of delta sedimentary system to variation of water and sediment in the Yellow River over past six decades

In order to find out the variation process of water-sediment and its effect on the Yellow River Delta, the water discharge and sediment load at Lijin from 1950 to 2007 and the decrease of water discharge and sediment load in the Yellow River Basin caused by human disturbances were analyzed by means of statistics. It was shown that the water discharge and sediment load into the sea were decreasing from 1950 to 2007 with serious fluctuation. The human activities were the main cause for decrease of water discharge and sediment load into the sea. From 1950 to 2005, the average annual reduction of water discharge and sediment load by means of water-soil conservation practices were 2.02×109 m3 and 3.41×108 t respectively, and the average annual volume by water abstraction for industry and agriculture were 2.52×1010 m3 and 2.42×108 t respectively. The average sediment trapped by Sanmenxia Reservoir was 1.45×108 t from 1960 to 2007, and the average sediment retention of Xiaolangdi Reservoir was 2.398×108 t from 1997 to 2007. Compared to the data records at Huanyuankou, the water discharge and sediment load into the sea decreased with siltation in the lower reaches and increased with scouring in the lower reaches. The coastline near river mouth extended and the delta area increased when the ratio of accumulative sediment load and accumulative water discharge into the sea (SSCT) is 25.4–26.0 kg/m3 in different time periods. However, the sharp decrease of water discharge and sediment load into the sea in recent years, especially the Yellow River into the sea at Qing 8, the entire Yellow River Delta has turned into erosion from siltation, and the time for a reversal of the state was about 1997.

Fluvial responses to environmental perturbations in the Northern Mediterranean since the Last Glacial Maximum

The numerical model HydroTrend, that produces daily time series of water discharge and sediment load to the ocean, is applied to three Mediterranean drainage basins to: (i) simulate the water and sediment flux changes to sedimentary basins through time and (ii) determine the impact of potential forcing factors on sediment and water fluxes to sedimentary basins and how this impact varied through time. Climate (precipitation, temperature and glacier equilibrium line) and drainage basin (basin elevation, drainage area and reservoir) reconstructions of the Po, Rhône and Têt river basins over the last 21 000 Cal. years B.P. are used as input to the model.Simulated sediment fluxes at the river mouth for the Po, Rhône and Têt River systems during the late Pleistocene were considerably higher compared to Holocene pristine sediment flux, with a factor 3.5, 2.4 and 2.4 respectively. For the Po River system and the Rhône River, deglaciation in the late Pleistocene is the main factor, responsible for these higher sediment fluxes. Drainage basin area change due to sea-level rise is the main cause of decrease in sediment flux for the Têt River system and to a certain extent for the Po River system. Man-made reservoirs reduced sediment flux to the ocean for the Po, Rhône and Têt rivers over the last 3–6 decades with a factor of 1.3, 3.8 and 2.4 respectively.Fluvial responses to climate and basin variations are reflected in the peak flood discharge and sediment concentration curves, where present-day water peak flood curves for all three rivers are the highest in the last 21 000Cal. years B.P. However, their associated sediment concentration curves show opposite results because of diminishing glacial area and the impact of reservoirs. The Têt River system has the ability to generate hyperpycnal plumes although the occurrence frequency changes over time. Prior to 15 500 Cal. years B.P. the river system area was extended due to the low sea level, causing a less favorable regime to generate hyperpycnal events. Presently sediment trapping due to man-made reservoirs alters the river ability to generate hyperpycnal events.

STEREOLOGICAL STUDY OF MICE PLACENTAL BARRIER AFTER PROTEIN MALNUTRITION

Investigations have been carried out on the effect of maternal protein free diet on the placenta of laboratory mice of Balb/C strain. The thickness of placental barrier was measured. Placental weight, fetal weight, fetal numbers were also calculated and histological study was also done. Animal husbandry and the day of conception were arranged. Pregnant mice were dissected at days (12th, 14th, and 18th) of gestation. Thirty placentas from mice on protein free diet and fifteen placentas from mice on control diet, were taken, stained by haematoxylin and eosin and examined under light microscope with screen. The following results are subsequently obtained: 1. Reduction in fetal number and weight of mice after protein malnutrition, in comparison to their control at the same stage of gestation. 2. Reduction in placental weight of mice after protein malnutrition, in comparison to their control at the same stage of gestation. 3. Reduction in the thickness of trophoblastic layers of placental barrier in mice after protein malnutrition, which are measured by using light microscope with screen and scientific ruler. 4. Morphological changes showed thin placental barrier, with basophilic cytoplasm and degenerated nuclei. Areas of degeneration infiltrated with phagocytic cells with increase in the number and size of blood vessels were seen. These changes may affect the placental function, which may be the main cause of decrease in fetal weight (intra uterine growth retardation), placental weight and fetal number.

Clinical Profile, Treatment, and Visual Outcome of Serpiginous Choroiditis

The purpose of this study was to report the clinical profile and management of patients with serpiginous choroiditis in a tertiary care referral center in India. In a retrospective cohort study, 107 eyes of 70 patients with serpiginous choroiditis seen between January 1995 and December 2002 were analyzed. Systemic steroids and immunosuppressives were the mainstay of therapy. Antituberculous and antiviral drugs were used in selected cases. There was male preponderance (7:3). Age at presentation ranged from 11 years to 52 years (mean 30.3 ± 9 years); 52.9% had bilateral involvement. Vision improved or maintained in 86% eyes and deteriorated in 15 eyes (14%). The main cause of decrease of vision was macular involvement. Improvement in vision and resolution of lesions in patients with serpiginous choroiditis can occur with combination therapy of systemic steroids and immunosuppressive agents. Serial examination at regular intervals is needed to monitor the disease progression, recurrences, and involvement of the other eye.

Creep resistance of similar and dissimilar weld joints of P91 steel

Two experimental weld joints, a similar weld joint of 9Cr–1Mo steel and a dissimilar weld joint of 9Cr–1Mo and 2.25Cr–1Mo steels, were fabricated by the TIG+E method and post-weld heating was applied. Creep testing was carried out at temperatures ranging from 525 to 625°C in the stress range 40–240 MPa. Creep rupture strength was evaluated using the Larson–Miller parameter. Extended metallography including transmission electron microscopy was performed and critical zones were indicated where fractures were concentrated during the creep exposure. At high temperatures rupture of the dissimilar weldment occurred in the heat affected zone (HAZ) of the weld metal while rupture of the similar weldment was located in the HAZ of the parent material. The processes of recovery seem to be the main causes of decrease in creep rupture strength of both weld joints in comparison to the parent materials.

Trace elements in viral hepatitis

In this study, serum trace elements, including selenium (Se), zinc (Zn), copper (Cu), were determined by using Atomic Absorption Spectrophotometer (SpectrAA 250 Plus Zeeman, Varian, Australia) in sera of patients with viral hepatitis (A, B, C, D, E) cases (n = 102), and statistically compared with the controls (n = 52). In viral hepatitis, Cu levels were found as 3.23 ± 1.02 mg/L, and this value was significantly higher than the control group (1.13 ± 0.21) (p < 0.01). Both, Se and Zn levels found to be significantly low in viral hepatitis cases (p < 0.01). While Se level was 81.4 ± 26.01 μg/L in viral hepatitis (n = 101), it was found to be 166.15 ± 4.58 μg/L in healthy individuals. Meanwhile, Zn levels were 0.230 ± 0.081 mg/L and 0.748 ± 0.392 mg/L in hepatitis cases (n = 101) and the control group, respectively. There was no difference amongst viral hepatitis groups classified in regard with agents and clinical manifestation, such as A, acute hepatitis B, chronic hepatitis B, C, D and E. Previously, it was indicated that absorption disorders in gastrointestinal system, especially in chronic cases, were not main causes of decrease of trace elements by iron and several other parameters in sera of the cases. Therefore, we suggest that decrease in Zn and Se levels and elevation in Cu levels are probably resulted from defence strategies of organism and induced by the hormone-like substances.

10 GHz-Range Surface Acoustic Wave Low Loss Filter Measured at Low Temperature

The 10 GHz-range surface acoustic wave (SAW) is of great importance in the field of physical acoustics and application of SAW devices, for example, in mobile and wireless communications. The temperature dependency of the propagation attenuation at 10 GHz-range is measured using the three-transducer system with an electrode width of less than 0.1 µm, which is fabricated using an electron beam exposure and lift-off technique. The results show that the attenuation at room temperature is about 1.5 dB/(100 λ) at 10 GHz. Next, the temperature dependency of the insertion loss of a floating electrode reflection type unidirectional transducer (FEUDT) whose electrodes are respectively fabricated from Al and the superconductor Nb, is investigated experimentally. In the case of Al-FEUDT at 8 GHz, the insertion loss at a low temperature is about 8.5 dB, which is 3.4 dB lower than the insertion loss at room temperature. The main cause of decrease in the insertion loss is the decrease in the resistivity of the very thin and narrow metal electrodes. The results of Nb-FEUDT show a marked decrease in the insertion loss around the critical temperature Tc=9.23 K.

Total ozone variations in middle Asia and dynamic meteorological processes in the atmosphere

The total ozone content over the former Soviet Middle Asia is compared with the heights and the temperatures at the 500 hPa and 100 hPa levels. There is a significant and negative correlation between the heights of the 100 hPa and 500 hPa levels and the total ozone content. The ozone column density is positively correlated with the temperature at 100 hPa and negatively correlated at 500 hPa. No observed time delay between ozone and temperature changes is found, indicating that the correlations are caused by dynamic processes. Ozone changes due to chemistry have time constants at least of the order of days, but correspondingly large time delays are not found. It is concluded that the horizontal advection is connected with ascending and descending air streams, and they are the main causes of decrease and increase of total ozone content with time constants of the order of one day.

Grasshoppers (Orthoptera, Saltatoria) on alpine and dealpine riverbanks and their use as indicators for natural floodplain dynamics

AbstractGravel banks with sparse vegetation are typical habitats of braided alpine and dealpine floodplains. They are not only habitats for semiaquatic or hygrophilous organisms, but include also xerophilous elements: 17 species of grasshoppers were recorded in the floodplain of the Upper Isar (Bavaria, FRG). In the alpine region, two species (Bryodema tuberculata, Chorthippus pullus) occur only in floodplains, colonizing young gravel banks with sparse vegetation. Population dynamics and habitat selection of Bryodema tuberculata, studied on the Upper Isar for several years, are characterized by small scale movements of marked individuals between neighbouring gravel banks and fluctuations of the abundance on different sections of the gravel banks. Furthermore, the periodic desiccation of small watercourses is important for the dispersal of the females by walking. Historically widespread, today its distribution corresponds to the few remaining inundation areas. The main causes of decrease and extinction in most localities are man‐made changes in floodplain dynamics. The building of retention reservoirs and the diverting of streams for hydropower influenced succession in the downstream floodplains. Most of the gravel banks with sparse vegetation changed into willow thickets or pine forests. All remaining inundation areas should be protected. Bryodema tuberculata is a good indicator for the balance between progressing succession and the reorganization of gravel banks by floods.

Regional Decrease in the Number of White Storks (Ciconia c. ciconia) in Relation to Food Resources

-White Stork (Ciconia c. ciconia) numbers have been decreasing in the western part of Europe for at least 100 years. We investigated the main causes of this decrease by analysis of national and international stork census data and 19th century reports. Rainfall in the wintering areas (eastern and western Africa), taken as a relative measure for the winter food supplies, was positively correlated with the annual relative changes in number of pairs with nests in Oldenburg/Lower Saxony (Federal Republic of Germany) (1928-1984) and in Alsace (France) (1948-1970). During years with a high winter rainfall, storks arrived earlier in the breeding area and more pairs produced fledged young. The food link suggested by these data is supported by statistics on plagues of locusts and armyworms in Africa. Dates of arrival at the breeding area suggest that climatic changes have been an important cause of the initial decrease of the storks wintering in western Africa. Important causes of the decrease in the past decades were a decreased supply of locusts and drought in the wintering areas and, regionally, a deterioration of the habitat in the breeding area. We consider habitat change to be the main cause of the regional decrease of the storks wintering in eastern Africa.

新潟県における昭和 47 年産水稲の減収要因

新潟県における昭和 47 年産水稲の減収要因