Mercury levels in six species of Australian commercial fish

1980 ◽  
Vol 31 (4) ◽  
pp. 469 ◽  
Author(s):  
R Chvojka ◽  
RJ Williams

The total mercury content of six species of Australian commercial fish (John dory. Zeus faber: mirror dory. Zenopsis nebulosus; tiger flathead, Neoplatycephalus richardsoni; rubberlip morwong, Nemadactylus douglasii; jackass morwong, Nemadactylus macroprerus; and sand whiting, Sillago ciliata) is reported. Total mercury content is regressed against fish length and the resultant equations and correlation coefficients are presented for each species. A length-frequency histogram derived from the Sydney Fish Market data and a length-mercury content curve are plotted as an overlay for each of the six species. The integrated average mercury content (mg/kg) has been calculated for each species and these are as follows: sand whiting, 0.08; rubberlip morwong, 0.13; tiger flathead, 0.14; John dory, 0.14; mirror dory, 0.15; and jackass morwong, 0.16. The graphical method adequately demonstrates the relationship between mercury levels and the commercial size range of particular species.

2021 ◽  
Vol 62 (2) ◽  
pp. 239-254
Author(s):  
A.V. Klyuchevskii ◽  
V.I. Grebenshchikova ◽  
M.I. Kuz’min ◽  
V.I. Dem’yanovicha ◽  
A.A. Klyuchevskaya

Abstract —The results of Hg content determination in the water of the Angara River source are considered in relationship with the seismic processes proceeding at different levels of the lithosphere in the Baikal Rift Zone (BRZ), the geodynamic rejuvenation of the South Baikal rifting attractor structure (RAS), and the time distribution of M ≥ 7 earthquakes which occurred at a significant distance from the water sampling station. The correlation coefficients calculated between the pairs Hg content–earthquake numbers n and Hg–logarithm of summary seismic energy lgΣES are most often low, thus indicating the absence of a statistically meaningful relationship between the remote seismic process and the dynamics of mercury release. However, the correlation coefficients in the vicinity of the Angara River source are high, thus proving the relationship of the mercury release with the deformation of this territory. The statistical validity of the «deformation–mercury release» cause-and-effect relationship is verified by the fact that strong geodynamic impacts precede all meaningful Hg release maxima. In the period 1997–1998, the South Baikal RAS produced the highest impact, being in the phase of the maximum geodynamic activity. The combined impact of the RAS and the South Baikal earthquake of 1999 resulted in a series of the maximum mercury contents within 1999–2000. The subsequent gradual relaxation of the RAS activity led to a reduction in the average annual Hg content. Remote M ≥ 7 earthquakes and close strong earthquakes of the BRZ are responsible for the significant Hg release maxima. The predicted trend of the average annual Hg contents is their considerable increase in the fields of fluid discharge of faults under the powerful geodynamic impact of the RAS or strong earthquake. We assume that in the study lithosphere area, the powerful geodynamic impact caused an opening of fault zones leading to decompression with boiling and degassing of mercury and its rapid rise to the surface.


1958 ◽  
Vol 9 (4) ◽  
pp. 526 ◽  
Author(s):  
AG Nicholls

Counts of eggs stripped from brown and rainbow trout show that over a sufficiently large size range the relationship to fish length is curvilinear. A direct relationship exists between egg numbers and fish weights. Brown trout from the Great Lake do not yield the expected number at larger sizes. The yield from rainbow trout is higher than that from brown.


2020 ◽  
Vol 29 (3) ◽  
pp. 429-435
Author(s):  
Patricia C. Mancini ◽  
Richard S. Tyler ◽  
Hyung Jin Jun ◽  
Tang-Chuan Wang ◽  
Helena Ji ◽  
...  

Purpose The minimum masking level (MML) is the minimum intensity of a stimulus required to just totally mask the tinnitus. Treatments aimed at reducing the tinnitus itself should attempt to measure the magnitude of the tinnitus. The objective of this study was to evaluate the reliability of the MML. Method Sample consisted of 59 tinnitus patients who reported stable tinnitus. We obtained MML measures on two visits, separated by about 2–3 weeks. We used two noise types: speech-shaped noise and high-frequency emphasis noise. We also investigated the relationship between the MML and tinnitus loudness estimates and the Tinnitus Handicap Questionnaire (THQ). Results There were differences across the different noise types. The within-session standard deviation averaged across subjects varied between 1.3 and 1.8 dB. Across the two sessions, the Pearson correlation coefficients, range was r = .84. There was a weak relationship between the dB SL MML and loudness, and between the MML and the THQ. A moderate correlation ( r = .44) was found between the THQ and loudness estimates. Conclusions We conclude that the dB SL MML can be a reliable estimate of tinnitus magnitude, with expected standard deviations in trained subjects of about 1.5 dB. It appears that the dB SL MML and loudness estimates are not closely related.


2019 ◽  
Vol 118 (9) ◽  
pp. 118-126
Author(s):  
Augusty P. A ◽  
Jain Mathew

The study evaluates the relationship between Emotional Intelligence and Leadership Effectiveness through a Systematic Review of Literature. The relationship has been evaluated in two steps. First, a Systematic review of literature was done to provide a theoretical framework to link the dimensions of Emotional Intelligence to the elements of effective leadership. Meta-analysis was then used to consolidate empirical evidence of the relationship. The studies for the meta-analysis were sourced from Pro Quest and EBSCO and the correlation coefficients of the studies were analysed. Only articles that presented the direct relationship between the variables were included in the study. The results of the analysis revealed a strong, statistically significant relationship between emotional intelligence and effective leadership. The findings of the study provide evidence for the proposition that Emotional Intelligence and Leadership Effectiveness are interrelated.


Author(s):  
А. I. Grabovets ◽  
V. P. Kadushkina ◽  
S. А. Kovalenko

With the growing aridity of the climate on the Don, it became necessary to improve the methodology for conducting the  breeding of spring durum wheat. The main method of obtaining the source material remains intraspecific step hybridization. Crossings were performed between genetically distant forms, differing in origin and required traits and properties. The use of chemical mutagenesis was a productive way to change the heredity of genotypes in terms of drought tolerance. When breeding for productivity, both in dry years of research and in favorable years, the most objective markers were identified — the size of the aerial mass, the mass of grain per plant, spike, and harvest index. The magnitude of the correlation coefficients between the yield per unit area and the elements of its structure is established. It was most closely associated with them in dry years, while in wet years it decreased. Power the correlation of the characteristics of the pair - the grain yield per square meter - the aboveground biomass averaged r = 0.73, and in dry years it was higher (0.91) than in favorable ones (0.61 - 0.70) , between the harvest and the harvest index - r = 0.81 (on average). In dry years, the correlation coefficient increased to 0.92. Research data confirms the greatest importance of the mass of grain from one ear and the plant in the formation of grain yield per unit area in both dry and wet years. In dry years, the correlation coefficient between yield and grain mass per plant was on average r = 0.80; in favorable years, r = 0.69. The relationship between yield and grain mass from the ear was greater — r = 0.84 and r = 0.82, respectively. Consequently, the breeding significance of the aboveground mass and the productivity of the ear, as a criterion for the selection of the crop, especially increases in the dry years. They were basic in the selection.


2019 ◽  
Vol 47 (12) ◽  
pp. 1-10
Author(s):  
Hongyun Lyu ◽  
Ningjian Liang ◽  
Zhen Guo ◽  
Rogelio Alejo Rodriguez

In this study we examined the differences in implicit collective self- esteem between Gelao and Han teenagers, using the Implicit Association Test. We also explored the relationship between participants' implicit and explicit collective self-esteem with the Implicit Association Test and the Explicit Collective Self-Esteem Scale. Participants were 169 teenagers residing in Gelao regions in China. The results showed that both Gelao and Han participants had an implicit collective self-esteem effect (i.e., tended to associate their own ethnic group with positive words and the other ethnic group with negative words), and this effect was significantly higher among Gelao than among Han participants. Further, scores on the importance-to-identity subscale of the Explicit Collective Self-Esteem scale were significantly higher in the Gelao versus the Han group. The correlation coefficients between implicit and explicit collective self-esteem for both groups were very low. The significance of the study findings is discussed.


Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3119
Author(s):  
Yinjiao Su ◽  
Xuan Liu ◽  
Yang Teng ◽  
Kai Zhang

Mercury (Hg) is a toxic trace element emitted from coal conversion and utilization. Samples with different coal ranks and gangue from Ningwu Coalfield are selected and investigated in this study. For understanding dependence of mercury distribution characteristics on coalification degree, Pearson regression analysis coupled with Spearman rank correlation is employed to explore the relationship between mercury and sulfur, mercury and ash in coal, and sequential chemical extraction method is adopted to recognize the Hg speciation in the samples of coal and gangue. The measured results show that Hg is positively related to total sulfur content in coal and the affinity of Hg to different sulfur forms varies with the coalification degree. Organic sulfur has the biggest impact on Hg in peat, which becomes weak with increasing the coalification degree from lignite to bituminous coal. Sulfate sulfur is only related to Hg in peat or lignite as little content in coal. However, the Pearson linear correlation coefficients of Hg and pyritic sulfur are relatively high with 0.479 for lignite, 0.709 for sub-bituminous coal and 0.887 for bituminous coal. Hg is also related to ash content in coal, whose Pearson linear correlation coefficients are 0.504, 0.774 and 0.827 respectively, in lignite, sub-bituminous coal and bituminous coal. Furthermore, Hg distribution is directly depended on own speciation in coal. The total proportion of F2 + F3 + F4 is increased from 41.5% in peat to 87.4% in bituminous coal, but the average proportion of F5 is decreased from 56.8% in peat to 12.4% in bituminous coal. The above findings imply that both Hg and sulfur enrich in coal largely due to the migration from organic state to inorganic state with the increase of coalification degree in Ningwu Coalfield.


Author(s):  
Agnieszka Jankowska ◽  
Joanna Janiszewska-Olszowska ◽  
Katarzyna Grocholewicz

Nose shape, size, and inclination influence facial appearance, but few studies concern the relationship between the nasal profile and craniofacial structures. The objective of this study was to analyze association of nasal cephalometric variables with skeletal structures, age, and sex. Cephalometric and nasal analysis was performed in 386 Polish orthodontic patients (aged 9–25 years). Student t-test and Mann–Whitney test were used to compare quantitative variables and Pearson’s or Spearman’s correlation coefficients—to find correlations. Soft tissue facial convexity angle correlates to Holdaway ratio, ANB (A-Nasion-B), and Wits appraisal. Nasal dorsum axis, nose length, nose depth (1) and nose depth (2), nose hump, lower dorsum convexity, and columella convexity increase with age. Nasal base angle, nasolabial angle, nasomental angle, soft tissue facial convexity and nasal bone angle decrease with age. Nasal base angle and nasomental angle are smaller in females. Thus, a relationship exists between nasal morphology and sagittal jaw configuration. Nasal parameters significantly change with age. Sexual dimorphism characterizes nasal bone angle and nasomental angle.


1997 ◽  
Vol 16 (11) ◽  
pp. 667-672 ◽  
Author(s):  
S. Halbach ◽  
L. Kremers ◽  
H. Willruth ◽  
A. Mehl ◽  
G. Welzl ◽  
...  

The number of amalgam-covered surfaces and the occlusal area of the fillings, the concentrations of total mercury in plasma, erythrocytes and urine, the urinary excretion rate, and the absorbed daily doses estimated by two separate methods from intra-oral Hg emission were determined in 29 volunteers with a low amalgam load. The transfer ofHg from the fillings via the oral cavity and blood to urinary excretion was evaluated by multiple correla tions between these variables. In addition, the combina tion of variables most representative of the entire compartmental transfer of amalgam Hg was determined. Urinary excretion (1), Hg concentration in plasma (2) and absorbed dose (3) were most closely correlated to each other, followed by correlations with the variables of the fillings (4). Correlation coefficients were 0.75 for variables 1 vs 2 and 2 vs 3, and 0.49 for variables 3 vs 4. It was concluded that variables 1-3 best reflected the transfer of mercury from amalgam fillings throughout the organism and that they were relatively insensitive to dietary mercury. The determination of total mercury in plasma and of its urinary excretion rate appears, under practical aspects, most suitable for the investigation of Hg uptake from amalgam.


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