scholarly journals The features of the coastal fronts in the Eastern Guangdong coastal waters during the downwelling-favorable wind period

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chaoyu Yang ◽  
Haibin Ye
Keyword(s):  
Coastal Waters ◽  
Meteorological Data ◽  
Pearson Correlation ◽  
Ocean Model ◽  
Ekman Pumping ◽  
Zonal Distribution ◽  
Factors Affecting ◽  
China Sea ◽  
Hybrid Coordinate Ocean Model ◽  
The Mean

AbstractA coastal front was detected in the eastern Guangdong (EGD) coastal waters during a downwelling-favorable wind period by using the diffuse attenuation coefficient at 490 nm (Kd(490)). Long-term satellite data, meteorological data and hydrographic data collected from 2003 to 2017 were jointly utilized to analyze the environmental factors affecting coastal fronts. The intensities of the coastal fronts were found to be associated with the downwelling intensity. The monthly mean Kd(490) anomalies in shallow coastal waters less than 25 m deep along the EGD coast and the monthly mean Ekman pumping velocities retrieved by the ERA5 dataset were negatively correlated, with a Pearson correlation of − 0.71. The fronts started in October, became weaker and gradually disappeared after January, extending southwestward from the southeastern coast of Guangdong Province to the Wanshan Archipelago in the South China Sea (SCS). The cross-frontal differences in the mean Kd(490) values could reach 3.7 m−1. Noticeable peaks were found in the meridional distribution of the mean Kd(490) values at 22.5°N and 22.2°N and in the zonal distribution of the mean Kd(490) values at 114.7°E and 114.4°E. The peaks tended to narrow as the latitude increased. The average coastal surface currents obtained from the global Hybrid Coordinate Ocean Model (HYCOM) showed that waters with high nutrient and sediment contents in the Fujian and Zhejiang coastal areas in the southern part of the East China Sea could flow into the SCS. The directions and lengths of the fronts were found to be associated with the flow advection.

scholarly journals SUBDUCTION OF SOUTH ATLANTIC SUBTROPICAL MODE WATERS

2013 ◽  
Vol 31 (3) ◽  
pp. 495
Author(s):  
Guilherme Nogueira Mill ◽  
Afonso De Moraes Paiva
Keyword(s):  
Mixed Layer ◽  
Ocean Model ◽  
South Atlantic ◽  
Ekman Pumping ◽  
The South ◽  
Subtropical Front ◽  
Mode Waters ◽  
Hybrid Coordinate Ocean Model ◽  
Winter Mixed Layer ◽  
Kinematic Method

ABSTRACT. The formation of the Subtropical Mode Waters (STMW) in the South Atlantic, part of the South Atlantic Central Water (SACW), by the subduction process, transferring mixed layer fluid into the permanent thermocline, is investigated using results of numerical simulations with the HYbrid Coordinate Ocean Model (HYCOM). Subduction rates were estimated by the kinematic method, adding the lateral induction of fluid through the sloping base of winter mixed layer with the vertical velocities at the base of winter mixed layer. Subduction rates above 100 m/year were found over the South Atlantic Subtropical Front, with maximum rates larger than 200 m/year in three distinct regions. The subduction pattern is dominated by the contribution of lateral induction, specially over the Subtropical Front, with rates significantly larger than the maximum rate of Ekman pumping. Different STMW were identified, associated with maximum layers thickness in isopycnals representative of upper and middle portion of SACW. The regions of maximum subduction rates were associated with the formation of the STMW.Keywords: mixed layer, ventilation, SACW, permanent thermocline, lateral induction. RESUMO. A formação de Águas Modais Subtropicais (AMS) no Atlântico Sul, que fazem parte da Água Central do Atlântico Sul (ACAS), transferindo fluido da camada de mistura para a termoclina permantente pelo processo de subducção, foi estudada a partir dos resultados de simulações numéricas com um modelo oceânico de coordenadas híbridas (HYCOM – Hybrid Coordinate Ocean Model). A subducção foi calculada pelo método cinemático, somando as contribuições da indução lateral de fluido através da base da camada de mistura e as velocidades verticais na base da camada de mistura de inverno. Foram encontradas taxas de subducção superiores a 100 m/ano ao longo da Frente Subtropical do Atlântico Sul, com três núcleos distintos de máxima subducção atingindo mais de 200 m/ano. A indução lateral mostrou-se o processo dominante na subducção, especialmente ao longo da frente, com taxas significativamente superiores ao bombeamento de Ekman. Foram identificadas diferentes AMS associadas às máximas espessuras de camadas representativas das porções média e superior da Água Central do Atlântico Sul (ACAS). As regiões de máximas taxas de subducção estão associadas à formação das AMS.Palavras-chave: camada de mistura, ventilação, ACAS, termoclina permanente, indução lateral.

Rediscovery and elaborate description of Platycephalus cultellatus Richardson, 1846 collected from the coastal waters of South China Sea

2018 ◽  
Vol 31 ◽  
pp. 32 ◽  
Author(s):  
Zhi Chen ◽  
Na Song ◽  
Jianwei Zou ◽  
Tianxiang Gao
Keyword(s):  
South China Sea ◽  
Genetic Distance ◽  
South China ◽  
Coastal Waters ◽  
Coi Gene ◽  
China Sea ◽  
Dorsal Fin ◽  
Meristic Counts ◽  
The Mean

Platycephalus cultellatus Richardson, 1846 was originally found and named in its type locality, Canton, Guangdong Province, China. However, this species was very rare in the coastal waters of China. Except that Qin et al. simply mentioned the original literature records of this species in 2013, no Chinese taxonomy books or publications have ever recorded or described local P. cultellatus. We collected P. cultellatus individuals from the coastal waters of South China Sea and gave valid identification and detailed descriptions of this species. The diacritically meristic counts were listed as follows: first dorsal fin usually with two small isolated spine anteriorly; second dorsal-fin and anal-fin usually with 13 soft rays; pectoral fin usually with 17–19 soft rays and without very small dark spots; caudal fin with 3–6 horizontal blackish bands, but without yellow marking on the middle when fresh; gill rakers 7–10 and pored lateral line scales 65–76. These conclusive characters were consistent with typical P. cultellatus individuals and could thoroughly separate them from other Platycephalus species. The fragment of cytochrome oxidase subunit I (COI) gene of mitochondrial DNA was also sequenced for the classification of specimens. The mean genetic distance within P. cultellatus was 0.25%, net genetic distance between P. cultellatus and other 14 species of the genus Platycephalus ranged from 11.59 to 25.48%. The phylogenetic analysis supported the validity of P. cultellatus existed in the coastal waters of South China Sea. This study will contribute to species identification within this genus distributed in Chinese seas.

scholarly journals Towards Understanding Variability in Droughts in Response to Extreme Climate Conditions over the Different Agro-Ecological Zones of Pakistan

2021 ◽  
Vol 13 (12) ◽  
pp. 6910
Author(s):  
Adil Dilawar ◽  
Baozhang Chen ◽  
Arfan Arshad ◽  
Lifeng Guo ◽  
Muhammad Irfan Ehsan ◽  
...  
Keyword(s):  
Pearson Correlation ◽  
Principal Component ◽  
Mitigation Strategies ◽  
Precipitation Extremes ◽  
Climate Mitigation ◽  
Mean Annual Temperature ◽  
Climate Extreme ◽  
Ecological Zones ◽  
The Mean ◽  
Agro Ecological Zones

Here, we provided a comprehensive analysis of long-term drought and climate extreme patterns in the agro ecological zones (AEZs) of Pakistan during 1980–2019. Drought trends were investigated using the standardized precipitation evapotranspiration index (SPEI) at various timescales (SPEI-1, SPEI-3, SPEI-6, and SPEI-12). The results showed that droughts (seasonal and annual) were more persistent and severe in the southern, southwestern, southeastern, and central parts of the region. Drought exacerbated with slopes of −0.02, −0.07, −0.08, −0.01, and −0.02 per year. Drought prevailed in all AEZs in the spring season. The majority of AEZs in Pakistan’s southern, middle, and southwestern regions had experienced substantial warming. The mean annual temperature minimum (Tmin) increased faster than the mean annual temperature maximum (Tmax) in all zones. Precipitation decreased in the southern, northern, central, and southwestern parts of the region. Principal component analysis (PCA) revealed a robust increase in temperature extremes with a variance of 76% and a decrease in precipitation extremes with a variance of 91% in the region. Temperature and precipitation extremes indices had a strong Pearson correlation with drought events. Higher temperatures resulted in extreme drought (dry conditions), while higher precipitation levels resulted in wetting conditions (no drought) in different AEZs. In most AEZs, drought occurrences were more responsive to precipitation. The current findings are helpful for climate mitigation strategies and specific zonal efforts are needed to alleviate the environmental and societal impacts of drought.

scholarly journals The role of serum β-trophin and endostatin in patients with polycystic ovary syndrome: Are they correlated?

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Wei Gong ◽  
Aikmu Bilixzi ◽  
Xinmei Wang ◽  
Yanli Lu ◽  
Li Wan ◽  
...  
Keyword(s):  
Polycystic Ovary Syndrome ◽  
Influencing Factors ◽  
Polycystic Ovary ◽  
Pearson Correlation ◽  
Healthy Controls ◽  
Newly Diagnosed ◽  
Ovary Syndrome ◽  
Factors Affecting ◽  
Main Factors

Abstract Background It’s necessary to investigate the serum β-trophin and endostatin (ES) level and its influencing factors in patients with newly diagnosed polycystic ovary syndrome (PCOS). Methods Newly diagnosed PCOS patients treated in our hospital were selected, and healthy women who took physical examination during the same period as healthy controls. We detected and compared the related serum indicators between two groups, Pearson correlation were conducted to identify the factors associated with β-trophin and ES, and the influencing factors of β-trophin and ES were analyzed by logistic regression. Results A total of 62 PCOS patients and 65 healthy controls were included. The BMI, WHI, LH, FSH, TT, FAI, FBG, FINS, HOMA-IR, TC, TG, LDL, ES in PCOS patients were significantly higher than that of healthy controls, while the SHBG and HDL in PCOS patients were significantly lower than that of healthy controls (all p < 0.05). β-trophin was closely associated with BMI (r = 0.427), WHR (r = 0.504), FBG (r = 0.385), TG (r = 0.405) and LDL (r = 0.302, all p < 0.05), and ES was closely associated with BMI (r = 0.358), WHR (r = 0.421), FBG (r = 0.343), TC (r = 0.319), TG (r = 0.404, all p < 0.05). TG, BMI, WHR and FBG were the main factors affecting the serum β-trophin levels (all p < 0.05). FBG, TC and BMI were the main factors affecting the serum ES levels (all p < 0.05). The TG, β-trophin, ES level in PCOS patients with insulin resistance (IR) were significantly higher than that of those without IR (all p < 0.05). Conclusion Increased β-trophin is closely associated with increased ES in patients with PCOS, which may be the useful indicators for the management of PCOS.

Open-wedge high tibial osteotomy in patients with discoid lateral meniscus

2021 ◽  
Vol 29 (2) ◽  
pp. 230949902110173
Author(s):  
Hee-June Kim ◽  
Ji-Yeon Shin ◽  
Hyun-Joo Lee ◽  
Chul-Hee Jung ◽  
Kyeong-Hyeon Park ◽  
...  
Keyword(s):  
High Tibial Osteotomy ◽  
Lateral Meniscus ◽  
Lateral Compartment ◽  
Clinical Results ◽  
Discoid Lateral Meniscus ◽  
Tibial Osteotomy ◽  
Open Wedge ◽  
Factors Affecting ◽  
The Mean ◽  
Open Wedge Hto

Background: There are concerns about the progression of the lateral osteoarthritis (OA) should be taken into account when high tibial osteotomy (HTO) is performed in patients with discoid lateral meniscus (LM). This study evaluated the clinical results of HTO in patients with discoid LM and elucidated factors affecting the results. Methods: This study evaluated 32 female patients with varus deformity and medial OA. Patients with discoid LM (8 patients) or without discoid LM (24 patients) underwent open-wedge HTO. The mean age was 53.5 years and the mean follow-up period was 35 months. Clinical results, including the Hospital for Special Surgery (HSS) score, Knee Society knee score (KS) and function score (FS), were evaluated. The progression of OA in the lateral compartment was also evaluated. Finally, we evaluated the factors affecting the clinical results and OA progression in the lateral compartment. Results: Between two groups, all clinical scores were not different (p = 0.964, 0.963, and 0.559, respectively). Three of eight patients (37.5%) in the discoid group developed OA in the lateral compartment, whereas 2 of 24 patients (8.3%) in the control group developed such; however, this was not significantly different (p = 0.085). In discoid group, patients with undercorrection has higher KS relative to patients with acceptable correction (p = 0.044). Other clinical results and OA change in the lateral compartment were not affected by evaluated factors. Conclusions: Patients who underwent open-wedge HTO showed the satisfactory clinical results and lateral OA progression regardless of the presence or absence discoid LM. However, when discoid LM was present, patients with undercorrection showed higher KS in comparison with patients with acceptable correction.

scholarly journals Revisit of a Case Study of Spilled Oil Slicks Caused by the Sanchi Accident (2018) in the East China Sea

2021 ◽  
Vol 9 (3) ◽  
pp. 279
Author(s):  
Zhehao Yang ◽  
Weizeng Shao ◽  
Yuyi Hu ◽  
Qiyan Ji ◽  
Huan Li ◽  
...  
Keyword(s):  
East China Sea ◽  
Oil Spill ◽  
Oil Spills ◽  
Ocean Model ◽  
Sea Surface ◽  
East China ◽  
The East China Sea ◽  
Sar Images ◽  
China Sea ◽  
Spatial Coverage

Marine oil spills occur suddenly and pose a serious threat to ecosystems in coastal waters. Oil spills continuously affect the ocean environment for years. In this study, the oil spill caused by the accident of the Sanchi ship (2018) in the East China Sea was hindcast simulated using the oil particle-tracing method. Sea-surface winds from the European Centre for Medium-Range Weather Forecasts (ECMWF), currents simulated from the Finite-Volume Community Ocean Model (FVCOM), and waves simulated from the Simulating WAves Nearshore (SWAN) were employed as background marine dynamics fields. In particular, the oil spill simulation was compared with the detection from Chinese Gaofen-3 (GF-3) synthetic aperture radar (SAR) images. The validation of the SWAN-simulated significant wave height (SWH) against measurements from the Jason-2 altimeter showed a 0.58 m root mean square error (RMSE) with a 0.93 correlation (COR). Further, the sea-surface current was compared with that from the National Centers for Environmental Prediction (NCEP) Climate Forecast System Version 2 (CFSv2), yielding a 0.08 m/s RMSE and a 0.71 COR. Under these circumstances, we think the model-simulated sea-surface currents and waves are reliable for this work. A hindcast simulation of the tracks of oil slicks spilled from the Sanchi shipwreck was conducted during the period of 14–17 January 2018. It was found that the general track of the simulated oil slicks was consistent with the observations from the collected GF-3 SAR images. However, the details from the GF-3 SAR images were more obvious. The spatial coverage of oil slicks between the SAR-detected and simulated results was about 1 km2. In summary, we conclude that combining numerical simulation and SAR remote sensing is a promising technique for real-time oil spill monitoring and the prediction of oil spreading.

scholarly journals Faecal bacteria in Perna perna (Linnaeus, 1758) (Mollusca: Bivalvia) for biomonitoring coastal waters and seafood quality

2010 ◽  
Vol 58 (spe3) ◽  
pp. 29-35 ◽  
Author(s):  
Diego Igawa Martinez ◽  
Ana Júlia Fernandes Cardoso de Oliveira
Keyword(s):  
Coastal Waters ◽  
Microbiological Quality ◽  
Perna Perna ◽  
Clearance Rates ◽  
Bacterial Concentration ◽  
Allometric Relations ◽  
The Mean ◽  
Negative Impacts ◽  
Faecal Bacteria

Urban development in coastal areas is intense and leads to the increase of sewage outfall and other negative impacts as consequences. Thus, stringent regulations establishing limits to the microbiological contamination of water and seafood are needed. The objective of this study is to evaluate the usefulness of Enterococci and Thermotolerant Coliform densities in the flesh of mussels Perna perna as an alternative tool for monitoring the microbiological quality of coastal waters. The study also considers allometric relations applied to clearance rates to understand rates of bacterial concentration. Bacterial loads obtained in mussels' flesh were from 50 to 4,300 times greater than in the water sampled in the vicinity of the mussels and some were considered inappropriate for consumption even when the water presented no restrictions. The mean clearance rate obtained for Enterococci retention was 317.7 ml h-1 and this rate (CR) is related to the mussels' size (L) by the equation CR = 28.3229L1.6421. The results showed that bacterial densities in the mussels' tissues may reflect chronic contamination of the environment and that clearance rates are important for taking the best decision in situations where, for example, it is desired to introduce mussels for aquaculture and the evaluation of the water concerned is required.

The prediction of voluntary intake of grazing dairy cows

1986 ◽  
Vol 107 (1) ◽  
pp. 43-54 ◽  
Author(s):  
Lindsey Caird ◽  
W. Holmes
Keyword(s):  
Organic Matter ◽  
Measurement Techniques ◽  
Live Weight ◽  
Simple Equation ◽  
Factors Affecting ◽  
Farm Planning ◽  
Sward Height ◽  
The Mean ◽  
Major Factors ◽  
Grazing Dairy Cows

SUMMARYInformation on the total organic matter intake, concentrates supplied (C), live weight (LW), week of lactation (WL), milk yield (MY), herbage organic matter digestibility (HOMD), herbage mass, sward height (SHT) or herbage allowance (HAL) measured individually for 357 cows at one of three sites was assembled. Observed intake was compared with intakes predicted by existing intake equations and new prediction equations based on regression models or regression and least-squares constants were developed. Major factors affecting intake were MY, LW, WL, C and HAL or SHT. Although HOMD was correlated with intake, better predictions were obtained when HOMD was omitted. There were differences between sites possibly associated with differences in measurement techniques.The predictive value of some existing equations and new equations were tested against independent sets of data. A simple equation (A) based on MY and LW (Ministry of Agriculture, Fisheries and Food, 1975) gave satisfactory average predictions but the mean square prediction error (MSPE) was high. The equations of Vadiveloo & Holmes (1979) adjusted for bias gave a relatively low MSPE. The preferred new equations for grazing cattle included MY, LW, WL, C and HAL or SHT, and their MSPE were similar to or lower than for indoor equations.The discussion indicates that a simple equation (A) would give adequate predictions for farm planning. The more detailed equations illustrate the inter-relations of animal with sward conditions and concentrate allowances. Predicted intakes may deviate from actual intakes because of short-term changes in body reserves.

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