DISTRIBUTION FEATURES OF CURRENT SYSTEM IN NORTHERN CENTRAL VIETNAM COAST (HA TINH - THUA THIEN-HUE) DURING APRIL 2016

This paper presents the modeled results of general current pattern (daily average value) in Northern Central Vietnam Coast (Ha Tinh - Thua Thien-Hue) during April 2016. Study results show that in general, current flowed from the North to the South with small and instable velocity (V ≈ 0.1 - 0.2 m/s). From 2nd to 6th April current flowed from the South to the North. From 7th to 29th April current flowed from the North to the South. During 13rd to 16th April current velocity was weak (V ≤ 0.1 m/s). In the southern region of Thua Thien-Hue province, the direction of current was instable (from 6th to 9th and from 20th to 22nd April current flowed from the South to the North). Current distribution pattern from modeled results was in accordance with the propagation characteristics of surface water temperatures in the studied area through data analysis of satellite images.

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Presence and Quantification of Microplastic in Urban Tap-Water

10.21203/rs.3.rs-117255/v1 ◽

2020 ◽

Author(s):

Claudia B. Pratesi ◽

Maria Aparecida A.L. Santos Almeida ◽

Geysa S. Cutrim Paz ◽

Marcelo H. Ramos Teotonio ◽

Felipe Mendes dos Santos Cardia ◽

...

Keyword(s):

Tap Water ◽

The South ◽

Plastic Pollution ◽

Wing Area ◽

Health Crisis ◽

Toxicological Effect ◽

The North ◽

Study Results ◽

The Mean ◽

Number Of Particles

Abstract Background: Plastic pollution is a rapidly growing environmental and human health crisis, with no sign of improvement. Since 2012 the number of studies on plastic pollution has quadrupled, and macro to nano-size plastics have been documented even in the planet's remote biomes. Studies have shown contamination by microplastics (MPs) in various types of food consumed by humans, including seafood, honey, sugar, salt, tap-water and bottled water and beer. The study's objective was to detect the possible contamination by MPs in drinking water samples collected from the two main residential and commercial areas of Brasília.Methods: A total of 32 samples of tap water were collected, 16 samples in the south zone, and 16 samples in the north zone of the city (respectively, South Wing and North Wing). Samples were processed and transferred to the Sedgewick-Rafter counting cell chamber. The presence of MPs particles was analyzed using a Nikon Eclipse fluorescence microscope.Results: MPs were found in 100% of the samples. The mean MPs per 500 ml found in the South Wing area was 97, while the mean number of particles in the North Wing area was 219.Conclusion: The study results reveal a disturbing amount of MP particles in Brasilia's tap-water. This surprising number of particles in tap-water is especially concerning considering that tap-water is not the only source of MPs to which people are exposed. The cumulative and toxicological effect of this chronic exposure is alarming.

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Analysis of the Water Circulation Structure in the Paldang Reservoir, South Korea

Applied Sciences ◽

10.3390/app10196822 ◽

2020 ◽

Vol 10 (19) ◽

pp. 6822

Author(s):

Hwangjeong Choi ◽

Ingu Ryu ◽

Minji Park ◽

Yongsik Song ◽

Soonju Yu ◽

...

Keyword(s):

Water Quality ◽

South Korea ◽

Discharge Rate ◽

Water Circulation ◽

The South ◽

Han River ◽

The North ◽

Study Results ◽

Instantaneous Discharge ◽

Layer Flow

In this study, results are presented for depth-specific hydraulic and water quality surveys, as well as meteorological observations, at key monitoring sites in the Paldang Reservoir, South Korea. These results were used to determine the water circulation characteristics that represent the main contributors to water quality changes. In the section before the confluence point of the two rivers, a different type of two-layer flow appeared for each. In the North Han River, backwater flowing backward in the upstream direction occurred in the surface layer, and was accompanied by two-layer flow, during the zero-discharge period of the Cheongpyeong Dam. On the other hand, in the South Han River, two-layer flow was observed in the upper layer in the downstream flow, and the thickness of upper and lower layers varied depending on the discharge rate of the Paldang Dam. Strong flow fluctuations were observed near the Paldang Dam (3 km upstream), and these were dependent on its instantaneous discharge rate. In particular, if the instantaneous discharge from the Paldang Dam remained below 400 m3/s for several days, the flow velocity in the lower layer decreased below 2 cm/s or no flow occurred. The comparison between flows during different periods associated with depth-specific water temperature variations showed that the average flow prevailed across all layers in the downstream direction at all monitoring sites during the vertical mixing period. In contrast, spatiotemporal variations in flow, such as two-layer flow and backwater, were observed during the stratification period in the South Han River and the North Han River. This led to increased residence times and vertical stability, thus creating favorable conditions for algal blooms.

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From meteorological to hydrological drought using standardised indicators

Hydrology and Earth System Sciences ◽

10.5194/hess-20-2483-2016 ◽

2016 ◽

Vol 20 (6) ◽

pp. 2483-2505 ◽

Cited By ~ 115

Author(s):

Lucy J. Barker ◽

Jamie Hannaford ◽

Andrew Chiverton ◽

Cecilia Svensson

Keyword(s):

Time Series ◽

Hydrological Drought ◽

Annual Rainfall ◽

Strongly Correlated ◽

Propagation Characteristics ◽

The South ◽

Drought Characteristics ◽

The North ◽

The Uk ◽

Hydrological Droughts

Abstract. Drought monitoring and early warning (M & EW) systems are a crucial component of drought preparedness. M & EW systems typically make use of drought indicators such as the Standardised Precipitation Index (SPI), but such indicators are not widely used in the UK. More generally, such tools have not been well developed for hydrological (i.e. streamflow) drought. To fill these research gaps, this paper characterises meteorological and hydrological droughts, and the propagation from one to the other, using the SPI and the related Standardised Streamflow Index (SSI), with the objective of improving understanding of the drought hazard in the UK. SPI and SSI time series were calculated for 121 near-natural catchments in the UK for accumulation periods of 1–24 months. From these time series, drought events were identified and for each event, the duration and severity were calculated. The relationship between meteorological and hydrological drought was examined by cross-correlating the 1-month SSI with various SPI accumulation periods. Finally, the influence of climate and catchment properties on the hydrological drought characteristics and propagation was investigated. Results showed that at short accumulation periods meteorological drought characteristics showed little spatial variability, whilst hydrological drought characteristics showed fewer but longer and more severe droughts in the south and east than in the north and west of the UK. Propagation characteristics showed a similar spatial pattern with catchments underlain by productive aquifers, mostly in the south and east, having longer SPI accumulation periods strongly correlated with the 1-month SSI. For catchments in the north and west of the UK, which typically have little catchment storage, standard-period average annual rainfall was strongly correlated with hydrological drought and propagation characteristics. However, in the south and east, catchment properties describing storage (such as base flow index, the percentage of highly productive fractured rock and typical soil wetness) were more influential on hydrological drought characteristics. This knowledge forms a basis for more informed application of standardised indicators in the UK in the future, which could aid in the development of improved M & EW systems. Given the lack of studies applying standardised indicators to hydrological droughts, and the diversity of catchment types encompassed here, the findings could prove valuable for enhancing the hydrological aspects of drought M & EW systems in both the UK and elsewhere.

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GENETIC DIVERSITY OF FISH (MUGIL CEPHALUS L.) IN VIETNAM USING SSR MARKERS

Vietnam Journal of Biotechnology ◽

10.15625/1811-4989/16/2/13436 ◽

2018 ◽

Vol 16 (2) ◽

pp. 267-272

Author(s):

Tran Thi Viet Thanh ◽

Phan Ke Long ◽

Jean Dominique Durand ◽

Dinh Thi Phong

Keyword(s):

Genetic Diversity ◽

Polymorphic Information Content ◽

Polymorphic Marker ◽

Mugil Cephalus ◽

The South ◽

Average Value ◽

The North ◽

Distribution Ranges ◽

Gulf Of Tonkin ◽

Relationship Of

The flathead grey mullet species (Mugil cephalus L.) Vietnam is an euryhaline fish whose distribution ranges from the North to the South. Currently, M. cephalus is facing the threat of overexploitation, and the number of individuals in most populations is declining fast. In order to conserve the species in Vietnam, it is necessary to evaluate its genetic diversity. Therefore, this study was carried out in Vietnam from August 2012 to June 2015. The results of our study provided the analysis for 12 locus microsatellites (SSR) from 70 mature individuals (standard length > 25 cm). The study also identified a total of 35 alleles for all loci studied, among which 10 loci were polymorphic. Average value of polymorphic information content (PIC) for each polymorphic marker was 0.2889 (0.0289 to 0.5918). Coefficient heterozygous gene Ho = 0.942; He = 0.517; Fst = 0.216; Fis = - 0.8211 (Fis < 0). The genetic relationship of 70 specimens or M. cephalus in Vietnam were divided in three main groups according to three specific geographic distributions in the country, the Gulf of Tonkin, the Central and the South. There were also mixed clusters observed among the three studied regions. Individuals in close geographical distance often clustered together and formed separate groups, in which the level of molecular changes were quite low, 29% among populations, and 71% among individuals within the same population.

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From meteorological to hydrological drought using standardised indicators

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-12-12827-2015 ◽

2015 ◽

Vol 12 (12) ◽

pp. 12827-12875 ◽

Cited By ~ 8

Author(s):

L. J. Barker ◽

J. Hannaford ◽

A. Chiverton ◽

C. Svensson

Keyword(s):

Time Series ◽

Hydrological Drought ◽

Strongly Correlated ◽

Propagation Characteristics ◽

The South ◽

Drought Characteristics ◽

The North ◽

The One ◽

The Uk ◽

Hydrological Droughts

Abstract. Drought monitoring and early warning (M&EW) systems are a crucial component of drought preparedness. M&EW systems typically make use of drought indicators such as the Standardised Precipitation Index (SPI), but such indicators are not widely used in the UK. More generally, such tools have not been well developed for hydrological (i.e. streamflow) drought. To fill these research gaps, this paper characterises meteorological and hydrological droughts, and the propagation from one to the other using the SPI and the related Standardised Streamflow Index (SSI), with the objective of improving understanding of the drought hazard in the UK. SPI and SSI time series were calculated for 121 near-natural catchments in the UK for accumulation periods of 1–24 months. From these time series, drought events were identified and for each event, the duration and severity was calculated. The relationship between meteorological and hydrological drought was examined by cross-correlating the one month SSI with various SPI accumulation periods. Finally, the influence of climate and catchment properties on the drought characteristics and propagation were investigated. Results showed that at short accumulation periods meteorological drought characteristics showed little spatial variability, whilst hydrological drought characteristics showed fewer but longer and more severe droughts in the south and east than in the north and west of the UK. Propagation characteristics showed a similar spatial pattern with catchments underlain by productive aquifers, mostly in the south and east, having longer SPI accumulation periods strongly correlated with the one-month SSI. For catchments in the north and west of the UK, which typically have little catchment storage, standard-period annual average rainfall was strongly correlated to drought and propagation characteristics. However, in the south and east, catchment properties describing storage, such as base flow index, percentage of highly productive fractured rock and typical soil wetness, were more influential on drought characteristics. This knowledge forms a basis for more informed application of standardised indicators in the UK in future, which could aid in the development of improved M&EW systems. Given the paucity of studies applying standardised indicators to hydrological droughts, and the diversity of catchment types encompassed here, the findings could prove valuable for enhancing the hydrological aspects of M&EW systems elsewhere in the world.

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Does where mothers live matter? Regional variations in factors influencing place of child delivery in Nigeria

Journal of Biosocial Science ◽

10.1017/s0021932020000747 ◽

2020 ◽

pp. 1-21

Author(s):

Tunde A. Alabi ◽

Sonnen Atinge ◽

Chibuike Ejim ◽

Samuel O. Adejoh

Keyword(s):

Health Care ◽

Rural Women ◽

Access To Health Care ◽

Care Facility ◽

First Trimester ◽

Health Care Facilities ◽

The South ◽

The North ◽

Study Results ◽

Care Facilities

Abstract Utilization of health care facilities for child delivery is associated with improved maternal and neonatal outcomes, but less than half of mothers use these for child delivery in Nigeria. This study investigated the factors associated with facility delivery in Nigeria, and their variation between the Northern and Southern parts of the country – two regions with distinct socio-cultural make-ups. The study included 33,924 mothers aged 15–49 who had given birth in the last 5 years preceding the 2018 Nigeria Demographic and Health Survey. Overall, higher age, being educated, being a Christian, being an urban resident, being exposed to mass media, making joint decisions with partner on health care, beginning antenatal visits in the first trimester and attending antenatal clinics frequently were found to be associated with improved use of a health care facility for child delivery. An average mother in Northern Nigeria had a 38% chance of having a facility-based delivery, whereas the likelihood in the South was 76%. When other factors were adjusted for, age and listening to the radio were significant predictors of facility-based delivery in the South but not in the North. In the North, Christians were more likely than Muslims to have a facility-based delivery, but the reverse was true in the South. Rural women in the South had a 16% greater chance of having a facility-based delivery than urban women in the North. The study results suggest that there is inequality in access to health care facilities in Nigeria, and the differences in the socio-cultural make-up of the two regions suggest that uniform intervention programmes may not yield similar results across the regions. The findings give credence to, and expand on, the Cosmopolitan-Success and Conservative-Failure Hypothesis.

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Response of the auroral electrojet indices to abrupt southward IMF turnings

Annales Geophysicae ◽

10.5194/angeo-28-1167-2010 ◽

2010 ◽

Vol 28 (5) ◽

pp. 1167-1182 ◽

Cited By ~ 13

Author(s):

J. W. Gjerloev ◽

R. A. Hoffman ◽

S. Ohtani ◽

J. Weygand ◽

R. Barnes

Keyword(s):

Solar Zenith Angle ◽

Current System ◽

Auroral Electrojet ◽

Lower Envelope ◽

Current Pattern ◽

Ionospheric Conductivity ◽

The North ◽

Ionospheric Current System ◽

Conductivity Gradient ◽

The Imf

Abstract. We present results from a study of the behavior of the auroral electrojet indices following abrupt southward turnings of the IMF Bz. The auroral electrojet indices are calculated from observations made by more than 100 ground based stations provided by the SuperMAG collaborators. Based on three simple criteria we selected 73 events. In each event the interval of analysis started at the time of the IMF Bz southward turning and ended 45 minutes later or at the onset of any abrupt energy unloading event in the magnetosphere, regardless of size. We refer to this period as the "pre-unloading phase". To isolate the dependence of the auroral electrojets on the solar induced ionospheric conductivity during this phase we separated the standard AU/AL indices into two new sets of indices defined by the upper and lower envelope of the north-south component for all sunlit stations (AUs/ALs) and for all stations in darkness (AUd/ALd). Based on events and statistical analyses we can conclude that following a southward turning of the IMF Bz the AUd/ALd indices show no measurable response while the AUs/ALs indices clearly intensify. The intensifications of AUs/ALs are dependent on the intensity of the solar wind driver (as measured by IMF Bz or the Akasofu ε parameter). The lack of AUd/ALd response does not depend on the intensity of any subsequent substorm. We find that during these isolated events the ionospheric current system is primarily confined to the sunlit ionosphere. This truncated version of the classical global DP-2 current system suggests that auroral electrojet continuity is not maintained across the terminator. Because of its conductivity dependence on the solar zenith angle, this truncated global current pattern is expected to be highly dependent on UT and season and thus can be asymmetric between hemispheres. Thus we argue that the global two-cell DP-2 current system is not a consequence only of a southward turning of the IMF but requires also the reduction of the conductivity gradient at the terminator.

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On the Leeuwin Current System and Its Linkage to Zonal Flows in the South Indian Ocean as Inferred from a Gridded Hydrography

Journal of Physical Oceanography ◽

10.1175/jpo-d-16-0170.1 ◽

2017 ◽

Vol 47 (3) ◽

pp. 583-602 ◽

Cited By ~ 18

Author(s):

Ryo Furue ◽

Kévin Guerreiro ◽

Helen E. Phillips ◽

Julian P. McCreary ◽

Nathaniel L. Bindoff

Keyword(s):

Indian Ocean ◽

Current System ◽

The South ◽

South Indian Ocean ◽

Zonal Flows ◽

Leeuwin Current ◽

The North ◽

South Indian ◽

The Tropics ◽

First Time

AbstractThe Leeuwin Current System (LCS) along the coast of Western Australia consists of the poleward-flowing Leeuwin Current (LC), the equatorward-flowing Leeuwin Undercurrent (LUC), and neighboring flows in the south Indian Ocean (SIO). Using geostrophic currents obtained from a highly resolved (⅛°) hydrographic climatology [CSIRO Atlas of Regional Seas (CARS)], this study describes the spatial structure and annual variability of the LC, LUC, and SIO zonal currents, estimates their transports, and identifies linkages among them. In CARS, the LC is supplied partly by water from the tropics (an annual mean of 0.3 Sv; 1 Sv ≡ 106 m3 s−1) but mostly by shallow (200 m) eastward flows in the SIO (4.7 Sv), and it loses water by downwelling across the bottom of this layer (3.4 Sv). The downwelling is so strong that, despite the large SIO inflow, the horizontal transport of the LC does not much increase to the south (from 0.3 Sv at 22°S to 1.5 Sv at 34°S). This LC transport is significantly smaller than previously reported. The LUC is supplied by water from south of Australia (0.2 Sv), by eastward inflow from the SIO south of 28°S (1.6 Sv), and by the downwelling from the LC (1.6 Sv) and in response strengthens northward, reaching a maximum near 28°S (3.4 Sv). North of 28°S it loses water by outflow into subsurface westward flow (−3.6 Sv between 28° and 22°S) and despite an additional downwelling from the LC (1.9 Sv), it decreases to the north (1.7 Sv at 22°S). The seasonality of the LUC is described for the first time.

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Long-term Cyclic Variations of Prominences, Green and Red Coronae over Solar Cycles

International Astronomical Union Colloquium ◽

10.1017/s0252921100064496 ◽

2000 ◽

Vol 179 ◽

pp. 201-204

Author(s):

Vojtech Rušin ◽

Milan Minarovjech ◽

Milan Rybanský

Keyword(s):

Emission Lines ◽

High Latitudes ◽

Green Line ◽

Solar Cycles ◽

The South ◽

Coronal Emission ◽

Local Maxima ◽

The North ◽

Cyclic Variations

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.

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PENERAPAN PEMBELAJARAN MATEMATIKA REALISTIK INDONESIA (PMRI) UNTUK MENINGKATKAN HASIL BELAJAR MATEMATIKA SISWA KELAS I SD NEGERI 011 BUKIT GAJAH KECAMATAN UKUI KABUPATEN PELALAWAN

Primary: Jurnal Pendidikan Guru Sekolah Dasar ◽

10.33578/jpfkip.v5i3.3931 ◽

2017 ◽

Vol 5 (3) ◽

pp. 451

Author(s):

Ipi Hanapiati

Keyword(s):

Learning Outcomes ◽

Mathematics Learning ◽

Learning Activities ◽

Average Value ◽

Study Results ◽

Teachers And Students

This research was motivated by the low results of students' mathematics learning. Of the 35students only 15 students (40.54%) who completed study results, while the average valueobtained by the students was 68.65. This study aims to increase the students' mathematicslearning through PMRI. This research is a class act who performed two cycles. Based on theresearch of learning outcomes and learning activities teachers and students expressedincreased. In the first cycle 1 meeting activities for teachers to get a score of 14 (70%), in thefirst cycle 2 meeting increased with a score of 15 (75%). In the second cycle 1 meeting obtaina score of 17 (85%) and the second cycle 2 meeting obtain a score of 18 (90%). Besides thestudent activity also increased in the first cycle of meeting one activity students obtain a scoreof 12 (60%), in the first cycle 2 meeting increased with a score of 16 (80%). In the secondcycle 1 meeting obtain a score of 17 (85%) and the second cycle 2 meeting obtain a score of17 (85%). The results of students' mathematics learning increases the basic score averagevalue obtained was 68.65 increase in the first cycle with an average value of 95.41 hasincreased in the second cycle with an average value of 97.97.

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