scholarly journals Actuopaleoichnology of a modern Bay of Fundy macro-tidal flat: analogy with a Mississippian tidal flat deposit (Hartselle Sandstone) from Alabama

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6975
Author(s):  
Louis G. Zachos ◽  
Brian F. Platt
Keyword(s):  
Tidal Flat ◽  
Depositional Environment ◽  
Exposure Period ◽  
Hydrodynamic Characteristics ◽  
Bay Of Fundy ◽  
Grain Texture ◽  
Tidal Regime ◽  
Low Degree ◽  
High Degree ◽  
High Diversity

Trace fossil zonation in the Hartselle Sandstone of Mississippian age (Chesterian: Visean-Serpukhovian) exposed on Fielder Ridge, Alabama is compared with modern macro-tidal flat ichnocoenoses on the Bay of Fundy at Lubec, Maine, and demonstrated to be analogous by sedimentologic and ichnotaxonomic criteria. The modern flat has minimal influence from either waves or freshwater influx, and can be divided into five distinct ichnocoenoses, characterized by surface traces (epichnia) and four sedimentologic facies defined by gross grain texture or hydrodynamic characteristics, but lacking significant surface traces. Several characteristics of tidal flat deposits in a fetch-limited, marine (i.e., non-estuarine), meso- to macro-tidal regime can be used to recognize similar environments as old as the late Paleozoic. These criteria include (1) limited influence of wind and waves on the depositional environment, (2) lack of significant freshwater influence and therefore any persistent brackish environments, (3) a distinct spatial distribution of microenvironments defined by substrate and exposure period, (4) high diversity of epichnial traces directly associated with microenvironments across the tidal flat, (5) generally low degree of reworking of traces by bioturbation but high degree of reworking by tidal currents, and (6) preservation of traces of predation and scavenging behavior on an exposed surface. These features, together with the regional depositional pattern of the Hartselle Sandstone interpreted as tide-influenced bars and shoals, support a meso- to macro-tidal interpretation of the depositional environment.

A Quantitative Study of the Phytoplankton in the Bay of Fundy and the Gulf of Maine (including Observations on Hydrography, Chemistry and Turbidity)

1935 ◽  
Vol 1 (5) ◽  
pp. 279-467 ◽  
Author(s):  
H. H. Gran ◽  
Trygve Braarud
Keyword(s):  
Gulf Of Maine ◽  
Vertical Mixing ◽  
Tidal Range ◽  
Bay Of Fundy ◽  
Surface Layers ◽  
Low Degree ◽  
Cloudy Weather ◽  
High Turbidity ◽  
High Tidal Range ◽  
High Degree

In the gulf of Maine life conditions of the phytoplankton were found to be in agreement with those described from the coastal waters of Northern Europe. The surface layers are during summer more or less stratified, indicating a fairly low degree of turbulence. Where the stratification is broken up, by vertical mixing, the waters are so transparent that the total effect of the turbulence on the productivity is favourable, the supply of nutrient salts resulting in an increase of the population, exceeding the loss by vertical transport. In the bay of Fundy, on account of the exceptionally high tidal range, the turbulence of the waters is so strong throughout the year that their nitrate and phosphate content nearly always was found to be high, even at the surface. The production of phytoplankton, therefore, can hardly be limited by the lack of nutrient salts. A relatively high turbidity of the waters and much cloudy weather make the productive zone shallow. Consequently the high degree of turbulence may even diminish the productivity of the waters by carrying the diatom cells down below the illuminated zone for a greater part of their life. A pronounced phytoplankton minimum in June probably is mainly a result of this effect of turbulence.

scholarly journals Diversity of Potamolithus (Littorinimorpha, Truncatelloidea) in a high-diversity spot for troglobites in southeastern Brazil: role of habitat fragmentation in the origin of subterranean fauna, and conservation status

2018 ◽  
Vol 25 ◽  
pp. 61-88
Author(s):  
Maria Elina Bichuette ◽  
Eleonora Trajano
Keyword(s):  
Conservation Status ◽  
Distribution Patterns ◽  
Shell Morphology ◽  
Karst Area ◽  
Southeastern Brazil ◽  
Small Areas ◽  
Cave System ◽  
Low Degree ◽  
High Degree ◽  
High Diversity

The Alto Ribeira karst area, southeastern Brazil, is a high-diversity area for troglobites. Three species of freshwater gastropodsPotamolithusoccur in the area:P.ribeirensis, only found in epigean waters at the Iporanga and Ribeira rivers;P.troglobius, which is endemic to the Areias cave system; andP.karsticus, a troglophilic species from Calcário Branco Cave and an epigean stream nearby. We investigated their distribution based on shell morphology and internal anatomy of epigean species, troglophilic populations, and troglobitic species. Distribution patterns ofPotamolithuswere compared to those of other aquatic taxa from the region (such as crustaceans and fishes). Besides the three species already described for the region, we recorded 12 additional ones, for a total of 15 species/morphs (six troglobites, seven troglophiles, and two epigean).Potamolithusspp. are restricted to micro-basins and/or caves, showing small areas of distribution and probably a high degree of endemism. Geomorphology (irregular landscape, with limestone outcrops intercalated with insoluble rocks, which probably act as geographic barriers for cave populations), paleoclimatic evidence, and ecological/biological factors, such as the low degree of mobility of these gastropods (sedentary habit), explain the distributional patterns. We observed troglomorphisms such as reduction/absence of eyes and pigmentation (body and periostracum), and a coiled intestine. Apparently, there is no cause-and-effect between miniaturization and intestine coiling forPotamolithus, in contrast to observations for other cave snails.Potamolithussnails are threatened in the region due to water pollution, uncontrolled tourism, and overcollection.

scholarly journals Clay Minerals and Detrital Material in Paleocene–Eocene Biogenic Siliceous Rocks (Sw Western Siberia): Implications for Volcanic and Depositional Environment Record

Geosciences ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 162
Author(s):  
Pavel Smirnov ◽  
Oksana Deryagina ◽  
Nadezhda Afanasieva ◽  
Maxim Rudmin ◽  
Hans-Jürgen Gursky
Keyword(s):  
Clay Minerals ◽  
Depositional Environment ◽  
Western Siberia ◽  
Ultramafic Rocks ◽  
Burial Diagenesis ◽  
Detrital Material ◽  
Siliceous Rocks ◽  
Low Degree ◽  
Provenance Areas ◽  
High Degree

The paper presents the results of a study on clay minerals and detrital material of biosiliceous rocks (Paleocene–Eocene) from three sections in the Transuralian region. The authigenic processes in sediments resulted in the formation of dioctahedral clay minerals (illite, smectite) and insignificant amounts of sulfide phases (pyrite, hydrotroillite). Detrital minerals from the studied diatomites and diatomaceous clays often have a subangular and semi-rounded habit that is evidence of a low degree alteration of the sedimentary material in the provenance areas. The high degree of preservation of the bioclastic debris and the transformation of the limited volcanogenic substratum in clay minerals apparently was possible by initial burial diagenesis. The morphology of kaolinite and illite suggests that these mineral formations were caused by diagenesis with feldspars and smectites as a substrate for their formation. The smectite zone of weathering crust that developed on the adjacent land could have also served as a significant source of smectites entering the sea basin. The association with smectite in aggregates of mixed clayey composition indicates a sequential smectite-to-illite reaction via mixed-layered minerals. Such minerals as amphiboles, pyroxenes, and olivines, semi-stable to transportation and genetically associated with ultramafic rocks, form a significant part of the clastic fraction of the rock, indicating the proximity of provenance areas. This is the evident reason that the provenance areas made of mafic and ultramafic rocks played an essential role.

Stimulation of β-(l → 6)-glucanase production by oxidized pustulan

1972 ◽  
Vol 18 (10) ◽  
pp. 1543-1550 ◽  
Author(s):  
Robert G. Brown
Keyword(s):  
Enzyme Activity ◽  
Isoelectric Focusing ◽  
Gel Filtration ◽  
Tween 80 ◽  
Sole Source ◽  
Cellulase Production ◽  
Low Degree ◽  
Degree Of Oxidation ◽  
High Degree ◽  
Stimulation Of

A strain of Penicillium lilacinum, isolated from soil, produced pustulanase, β-(1 → 3)-glucanase, (EC. 3.2.1.6) and cellulase (EC.3.2.1.4) when cultivated on a medium containing pustulan as the sole source of carbon. If pustulan was replaced by ketopustulan, the production of pustulanase was stimulated about 10-fold although the amount of stimulation was dependent on the degree of oxidation of pustulan. β-(1 → 3)-Glucanase production was stimulated slightly by ketopustulan; however, the degree of oxidation did not affect significantly the yield of this enzyme. Cellulase production was either unaffected by the oxidized polymer, or at higher degrees of oxidation, decreased. Tween 80 stimulated the production of the three enzymes in media containing ketopustulan with a low degree of oxidation but was inhibitory to pustulanase and cellulase production in media containing ketopustulan with a high degree of oxidation. A combination of gel filtration and isoelectric focusing revealed that each enzyme activity was attributable to at least two proteins.

scholarly journals Interactions Between Chill-Hours and Degree-Days Affect Carpogenic Germination in Monilinia vaccinii-corymbosi

2001 ◽  
Vol 91 (1) ◽  
pp. 77-83 ◽  
Author(s):  
H. Scherm ◽  
A. T. Savelle ◽  
P. L. Pusey
Keyword(s):  
Laboratory Experiments ◽  
Field Experiments ◽  
Degree Days ◽  
Carpogenic Germination ◽  
Conditioning Period ◽  
Low Degree ◽  
Heating Degree Days ◽  
Relationship Of ◽  
High Degree ◽  
The Relationship

The relationship of cumulative chill-hours (hours with a mean temperature <7.2°C) and heating degree-days (base 7.2°C) to carpogenic germination of pseudosclerotia of Monilinia vaccinii-corymbosi, which causes mummy berry disease of blueberry, was investigated. In two laboratory experiments, pseudosclerotia collected from rabbiteye blueberry in Georgia were conditioned at 5 to 6°C for 26 to 1,378 h prior to placement in conditions favorable for germination and apothecium development. The number of chill-hours accumulated during the conditioning period affected the subsequent proportion of pseudosclerotia that germinated and produced apothecia, with the greatest incidence of carpogenic germination occurring after intermediate levels of chilling (≈700 chill-hours). The minimum chilling requirement for germination and apothecium production was considerably lower than that reported previously for pseudo-sclerotia from highbush blueberry in northern production regions. The rate of carpogenic germination was strongly affected by interactions between the accumulation of chill-hours and degree-days during the conditioning and germination periods; pseudosclerotia exposed to prolonged chilling periods, once transferred to suitable conditions, germinated and produced apothecia more rapidly (after fewer degree-days had accumulated) than those exposed to shorter chilling periods. Thus, pseudosclerotia of M. vaccinii-corymbosi are adapted to germinate carpogenically following cold winters (high chill-hours, low degree-days) as well as warm winters (low chill-hours, high degree-days). Results were validated in a combined field-laboratory experiment in which pseudosclerotia that had received various levels of natural chilling were allowed to germinate in controlled conditions in the laboratory, and in two field experiments in which pseudosclerotia were exposed to natural chilling and germination conditions. A simple model describing the timing of apothecium emergence in relation to cumulative chill-hours and degree-days was developed based on the experiments. The model should be useful for better timing of field scouting programs for apothecia to aid in management of primary infection by M. vaccinii-corymbosi.

Leadership Styles of Public Schools Principals in the City of Hail in the Kingdom of Saudi Arabia: أنماط القيادة لدى مدراء مدارس التعليم العام في مدينة حائل في المملكة العربية السعودية

2021 ◽  
Vol 5 (41) ◽  
pp. 161-138
Author(s):  
Fahad Husain Alshammari Fahad Husain Alshammari
Keyword(s):  
Public Schools ◽  
Leadership Style ◽  
School Principals ◽  
Statistical Significance ◽  
Point Of View ◽  
Years Of Experience ◽  
Public School Principals ◽  
Low Degree ◽  
Study Population ◽  
High Degree

    This study aimed to: Identify the leadership style prevailing among public school principals in Hail from the teachers ’point of view, and to reveal the statistical significance of the differences in the estimates of the study sample individuals of the leadership style prevailing among school principals, which may due to variables of (educational stage, number of years of experience, and specialization). The researcher used the descriptive method, and prepared a questionnaire consisting of (24) statements distributed to (3) dimensions, which are: Democratic style, authoritarian style and chaotic style. The current study population included all the teachers of public education schools in Hail, who numbered (9390) teachers. The questionnaire was applied to a random sample of (296) teachers. The study found a set of results, the most important of which are: The prevailing leadership style among school principals is the democratic style, followed by the authoritarian style, and then the chaotic style. Where the democratic style obtained a mean (4.18) and a high degree of approval from the study sample, while the domineering style obtained a mean (1.83) and a low degree of approval from the study sample, and the chaotic style obtained an average (1.73) and a low degree of approval. Very members of the study sample. The results also showed that there are statistically significant differences in the degree of the study sample’s estimates of the leadership style prevailing among school principals due to the variable of years of experience, while there are no statistically significant differences in the degree of the study sample’s estimates of the leadership style prevailing among school principals due to the variables of the educational stage or specialization. In light of these results, the researcher recommended organizing training courses for school principals to enlighten them about the modern trends in educational leadership, and urged school principals to follow the democratic style of administration.

Depositional environment and characteristics of Late Eocene carbonaceous swampy tidal flat facies in the Fayoum Basin, Egypt

2018 ◽  
Vol 200 ◽  
pp. 45-58 ◽  
Author(s):  
Thomas Gentzis ◽  
Humberto Carvajal-Ortiz ◽  
Selim S. Selim ◽  
Sameh S. Tahoun ◽  
Moataz El-Shafeiy ◽  
...  
Keyword(s):  
Tidal Flat ◽  
Depositional Environment ◽  
Late Eocene

scholarly journals Genetic linkage map of Phaseolus vulgaris and identification of QTLs responsible for resistance to Xanthomonas axonopodis pv. phaseoli

2003 ◽  
Vol 28 (1) ◽  
pp. 5-10 ◽  
Author(s):  
Amaury S. Santos ◽  
Ricardo E. Bressan-Smith ◽  
Messias G. Pereira ◽  
Rosana Rodrigues ◽  
Claudia F. Ferreira
Keyword(s):  
Phaseolus Vulgaris ◽  
Common Bean ◽  
Linkage Map ◽  
Linkage Groups ◽  
Resistant Genotype ◽  
Xanthomonas Axonopodis ◽  
Low Degree ◽  
Phenotypic Variations ◽  
Genomic Regions ◽  
High Degree

Common bean (Phaseolus vulgaris) cultivars with a high degree of resistance to Xanthomonas axonopodis pv. phaseoli (Xap) are not available in Brazil. Despite many studies, a low degree of resistance to Xap continues to exist due to its complex genetic inheritance, which is not well known. The objectives of this research were to complement a common bean genetic map based on the cross between a susceptible genotype 'HAB-52' and a resistant genotype 'BAC-6', and to map and analyze genomic regions (quantitative trait loci – QTLs) related to Xap resistance. Eleven linkage groups were determined using 143 RAPD markers, covering 1,234.5 cM of the genome. This map was used to detect QTLs associated with Xap resistance on leaves and pods. The averages of disease severity on leaves (represented by the transformed disease index – TDI) and pods (represented by the diameter of lesion on pods – DLP) were added to the data of the linkage map. Five TDI QTLs and only one LDP QTL were detected. The TDI QTLs were placed in the A, B, G and J linkage groups, with phenotypic variations ranging from 12.7 to 71.6%. The DLP QTL explained 12.9% of the phenotypic variation and was mapped in a distinct linkage group. These results indicate that there are different genes involved in the control of resistance on leaves and pods.

scholarly journals TOLAK UKUR FUNGSI HATI BERDASARKAN DERAJAT FIBROSIS PENYAKIT HATI KRONIS (Liver Function Parameters based on Degree of Liver Fibrosis in Chronic Liver Disease)

2018 ◽  
Vol 21 (1) ◽  
pp. 57
Author(s):  
Rahmafitria Rahmafitria ◽  
Mutmainnah Mutmainnah ◽  
Ibrahim Abdul Samad
Keyword(s):  
Liver Disease ◽  
Liver Fibrosis ◽  
Liver Function ◽  
Chronic Liver Disease ◽  
Total Bilirubin ◽  
Chronic Liver ◽  
Low Degree ◽  
Significant Difference ◽  
The Mean ◽  
High Degree

Evaluating the degree of liver fibrosis degree is invasive as well as uncomfortable, therefore, non invasive examinations such as liverfunction tests and elastography (Fibro Scan) as a predictor‘s device of liver fibrosis degree are necessary. The aim of this study was toknow the differences of liver function parameters based on the fibrosis degree in patients with chronic liver disease. This study was a crosssectional design using data from chronic liver disease patients treated at the Dr. Wahidin Sudirohusodo Hospital. The elasticity of the liverwas measured using a fibro scan device during June 2010–July 2011. The analysis was carried out by ANOVA test on various parametersof liver function particularly on the fibrosis degree in chronic liver disease. In this study PT, albumin, total bilirubin and platelet countshowed a significant difference of 0.019, 0.009, 0.017 and 0.000 respectively. The mean values of PT and total bilirubin were significantlyhigher in the high degree of fibrosis compared to those with medium and low degree of fibrosis in the chronic liver disease patients. Basedon this study, the mean albumin levels and platelet count were significantly lower in the high degree of fibrosis compared with the mediumand low degree of fibrosis, however, no significant differences in AST, ALT, APTT and GGT were found.

scholarly journals A PERFORMANCE ANALYSIS OF REGIONAL BUDGET OF JAYAWIJAYA REGENCY FROM 2010 TO 2014

2017 ◽  
Vol 1 (3) ◽  
Author(s):  
Didi Yigibalom ◽  
Ida Ayu Purba Riani
Keyword(s):  
Central Government ◽  
Fiscal Decentralization ◽  
Overlay Analysis ◽  
External Funding ◽  
Revenue Growth ◽  
Low Degree ◽  
Regional Budget ◽  
Variant Analysis ◽  
High Degree ◽  
Budget Revenue

This study aims to assess performance of Regional Budget (APBD) which includes revenues, spending/expenditures and financing activities of Jayawijaya Government. The data used was the budgeted and realization of Revenue, Spending/Expenditure and Financing activities of Jayawijaya regency from 2010 to 2014. The analysis techniques used was a qualitative approach through various financial ratios. To calculate revenues performance this study employed Variant Analysis (differences of) Budget Revenue, Revenue Growth, Degree of Independence of the region, Regional Reliance to the central government, Degree of Decentralization, Local Tax Effectiveness and Overlay analysis to measure performance of the generated income. Meanwhile to measure expenditure used Variant Analysis (difference) Budgeted Expenditure, Growth of Regional Expenditure, Synchronization of Governmental Spending, Spending Effectiveness and Overlay analysis to measure overall spending/expenditures performance. Following the analysed data, the study obtained following results: 1) Jayawijaya’s revenue performance during 2010 to 2014 based on the overlay analysis was not good. The main caused was due to low degree of the region financial independence, high degree of fiscal dependence for external funding as well as the low degree of fiscal decentralization, 2) Spending/Expenditure Performance of Jayawijaya from 2010 to 2014 was good. This was because of the increasing growth of Jayawijaya’s spending/expenditure and the effectiveness of spending/expenditure in Jayawijaya. Keywords: Budget, Revenue, Spending/ Expenditure, Regional Budget Performance

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