scholarly journals Multiple sediment incorporation events in a continental magmatic arc: Insight from the metasedimentary rocks of the northern North Cascades, Washington (USA)

Geosphere ◽  
2021 ◽  
Author(s):  
Ann E. H. Hanson ◽  
Stacia M. Gordon ◽  
Kyle T. Ashley ◽  
Robert B. Miller ◽  
Elizabeth Langdon-Lassagne
Keyword(s):  
Detrital Zircon ◽  
Analytical Data ◽  
North Cascades ◽  
Detrital Zircon Geochronology ◽  
Magmatic Arc ◽  
Metasedimentary Rocks ◽  
The North ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

The rheology and composition of arc crust and the overall evolution of continental magmatic arcs can be affected by sediment incorporation events. The exhumed Cretaceous–Eocene North Cascades arc exposes abundant metasedimentary rocks that were incorporated into the arc during multiple events. This study uses field relationships, detrital zircon geochronology, bulk rock geochemistry, geothermometry, and quartz­in­garnet geobarometry to distinguish approximate contacts and emplacement depths for different metasedimentary units to better understand their protolith incorporation history and impact on the arc. The Skagit Gneiss Complex is one of the main deep crustal units of the North Cascades arc. It includes metasedimentary rocks with distinct detrital zircon signatures: Proterozoic–Cretaceous (Group 1) or Triassic–Cretaceous (Group 2) zircon populations. Both metasedimentary groups achieved near­ peak metamorphic conditions of 640–800 °C and 5.5–7.9 kbar; several Group 2 samples reveal the higher pressures. A third group of metasedimentary rocks, which was previously interpreted as metamorphosed equivalents of backarc sediments (Group 3), exhibited unimodal Triassic or bimodal Late Jurassic–Early Cretaceous detrital zircon signatures and achieved near­peak conditions of 570–700 °C and 8.7–10.5 kbar. The combined field and analytical data indicate that protoliths of Group 1 and Group 2 metasedimentary rocks were successively deposited in a forearc basin and underthrusted into the arc as a relatively coherent body. Group 3 backarc sediments were incorporated into the arc along a transpressional step­over zone. The incorporation of both forearc and backarc sediments was likely facilitated by arc magmatism that weakened arc crust in combination with regional transpression.

scholarly journals Origin and Geochemical Processes of Porewater in Clay-Rich Deposits in the North Jiangsu Coastal Plain, China

Geofluids ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Qin Ge ◽  
Xing Liang ◽  
Menggui Jin ◽  
Jing Li ◽  
Yan Liu
Keyword(s):  
Cation Exchange ◽  
Coastal Plain ◽  
Mineral Weathering ◽  
Geochemical Processes ◽  
Hydrochemical Evolution ◽  
Low Salinity ◽  
The North ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

The hydrogeochemical and stable isotope compositions of aquitard porewater samples from three boreholes were investigated to determine the origin, salinization, and hydrochemical evolution of water in the North Jiangsu coastal plain, China. Three porewater groups were identified based on the water-bearing subsystems. The total dissolved solids (TDS) of porewater samples highly varied from 0.03 to 26.1 g/L. Molar Cl/Br ratios and δ18O and δ2H data indicate that the source of Group 1 salinized porewater was the Holocene seawater, whereas Group 3 salinized samples were probably related to the remnant palaeoseawater of the Late Pleistocene. Group 2 samples had low salinity (TDS < 1 g/L) and undetectable Br− concentrations, which were probably recharged during a colder period and without evidence of seawater involvement. The salinized porewater was likely diluted by freshwater, as evidenced by its depleted isotopes and low salinity relative to standard seawater. The ionic ratios and ionic deltas indicate that considerable water-rock interactions (e.g., cation exchange and mineral weathering) also accounted for the hydrochemical constituents of porewaters, and cation exchange seems to be more noticeable at low salinity.

ON CERTAIN SPECIES OF SATYRUS

1880 ◽  
Vol 12 (6) ◽  
pp. 109-115 ◽  
Author(s):  
W. H. Edwards
Keyword(s):  
North American ◽  
Species Group ◽  
North American Species ◽  
Cell Group ◽  
The North ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

Conclusion.—The North American species of this genus may be divided into three Groups, with several sub-groups. Group 1 comprises Pegala and all the larger species. Group 2 Silvestris and others. characterized by their small size, and the peculiar outline of the discal band on under side of hind wings, there being two long serrations against end of cell. This division will throw Meadii into Group 1, in which the band has a rounded prominence against cell. Group 3 comprises Sthenele only.

Stratigraphic and taxonomic revision of the fossil vole remains (Rodentia, Microtinae) from the Lower Pleistocene deposits of eastern England

1986 ◽  
Vol 312 (1157) ◽  
pp. 431-485 ◽  
Keyword(s):  
The Netherlands ◽  
Taxonomic Revision ◽  
British Museum ◽  
The North ◽  
Microtine Rodents ◽  
Lower Pleistocene ◽  
Group 3 ◽  
Group 2 ◽  
Coastal Deposits ◽  
Group 1

We review the fossil microtine rodent assemblages from the Lower Pleistocene deposits in eastern England, consisting mainly of marine sediments of the Norwich Crag and Cromer Forest-bed Formations. Material from 17 localities, including the ‘Weybourne Crag’ of the Norfolk Coast, the inland ‘Norwich Crag’, and the Crag of the north Suffolk coast has been studied. The taxa Mimomys pliocaenicus, M.rex, M.blanci, M.newtoni, M.pitymyoides, M .altenburgensis and Clethrionomys are recognized. Mimomys pitymyoides and M.altenburgensis are described for the first time from Britain. The type material of Mimomys reidi and M.newtoni is redescribed, and we show that M.newtoni Major 1902 is a senior synonym of M.hungaricus (Kormos), thus resolving confusion that has existed in the literature. The prior name for the species described by M. A. C. Hinton ( Monograph of the voles and lemmings (Microtnae) living and extinct . London: British Museum (Natural History) 1926) as Mimomys newtoni appears to be Mimomys blanci van der Meulen 1973. No evidence has been found for mixing of faunas of different age at a single horizon or locality. Differences in crown height are demonstrated between samples of Mimomys pliocaenicus from different localities, and differences between localities in the presence and absence of various species are tabulated. This evidence combined with current interpretations of the stratigraphy leads us to recognize three faunal groups. Group 1 faunas contain Mimomys pliocaenicus, M.reidi (type level), M.newtoni (type level), M.pitymyoides, M.blanci and Clethrionomys . They come from coastal deposits previously termed ‘Weybourne Crag’ and currently considered to date from Pre-Pastonian a to Pastonian. The faunas are clearly later than group 2 faunas, which contain Mimomys pliocaenicus, M.reidi, M.newtoni (these three species less advanced than in group 1 faunas), M.rex and M.altenburgensis (these two species lacking in group 1 faunas). Group 2 faunas come from inland ‘Norwich Crag’ localities and crags in Suffolk yielding a Chillesford type pollen assemblage, which are currently considered to date from the Bramertonian stage. Group 3 faunas contain Mimomys pliocaenicus, M.reidi and M.blanci and are from coastal deposits at Covehithe and Easton Bavents associated with Baventian stage clays. The evidence from the microtine rodents confirms the relative position of the Bramertonian and Pre-Pastonian a stages, but does not yet allow conclusions to be drawn on the relative age of group 3 faunas or the deposits in which they occur. The fauna of the Pastonian stage still requires clarification, since it is not possible to allocate unambiguously to this stage any of the material described here. The British Lower Pleistocene assemblages are broadly similar to material from Tegelen, The Netherlands (Tiglian TC4-6) and to material from superimposed loess levels at Stranzendorf, Austria. The British assemblages are characterized by the presence of Mimomys pliocaenicus and the absence of species with unrooted teeth, indicating that they belong to the Mimomys superzone of the biostratigraphic system of A. J. van der Meulen ( Quaternaria 17, 1-144, 1973) corresponding to the Villanyian stage. On the basis of microtine evidence we suggest limits to the correlation of the Pre-Pastonian and Bramertonian stages with the Netherlands chronostratigraphy. These limits are earlier than suggested by other lines of evidence. Correlation of the Pre-Pastonian with part of the Eburonian and the Bramertonian with part of the Tiglian is thought to merit consideration.

In-vivo evaluation of the effect of cyanoacrylate on prosthetic vascular graft infection – does cyanoacrylate increase the severity of infection?

VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin
Keyword(s):  
Vascular Graft ◽  
Graft Infection ◽  
Vascular Graft Infection ◽  
Group 4 ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2 ◽  
Prosthetic Vascular Graft Infection ◽  
Group 1

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.

Abnormal Haemostasis and Blood Viscosity in Malignant Hypertension

1984 ◽  
Vol 52 (03) ◽  
pp. 253-255 ◽  
Author(s):  
C Isles ◽  
G D O Lowe ◽  
B M Rankin ◽  
C D Forbes ◽  
N Lucie ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Viscosity ◽  
Renal Damage ◽  
Antithrombin Iii ◽  
Plasma Viscosity ◽  
Malignant Hypertension ◽  
Fibrin Deposition ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

SummaryWe have previously shown abnormalities of haemostasis suggestive of intravascular coagulation in patients with malignant hypertension, a condition associated with retinopathy and renal fibrin deposition. To determine whether such abnormalities are specific to malignant hypertension, we have measured several haemostatic and haemorheological variables in 18 patients with malignant hypertension (Group 1), 18 matched healthy controls (Group 2), and 18 patients with non-malignant hypertension (Group 3) matched for renal pathology, blood pressure and serum creatinine with Group 1. Both Groups 1 and 3 had increased mean levels of fibrinogen, factor VIIIc, beta-thrombo- globulin, plasma viscosity and blood viscosity (corrected for haematocrit); and decreased mean levels of haematocrit, antithrombin III and platelet count. Mean levels of fast antiplasmin and alpha2-macroglobulin were elevated in Group 1 but not in Group 3. We conclude that most blood abnormalities are not specific to malignant hypertension; are also present in patients with non-malignant hypertension who have similar levels of blood pressure and renal damage; and might result from renal damage as well as promoting further renal damage by enhancing fibrin deposition. However increased levels of fibrinolytic inhibitors in malignant hypertension merit further investigation in relation to removal of renal fibrin.

Features of postoperative period in patients with chronic venous insufficiency: phlebectomy versus thermal ablation

2020 ◽  
pp. 64-75
Author(s):  
E. Burleva ◽  
O. Smirnov ◽  
S. Tyurin
Keyword(s):  
Postoperative Period ◽  
Chronic Venous Insufficiency ◽  
Thermal Ablation ◽  
Venous Insufficiency ◽  
Clinical Symptoms ◽  
Varicose Veins ◽  
Statistical Processing ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

The purpose of the study was to conduct a comparative assessment of the course of the postoperative period after phlebectomy and thermal ablation in patients with varicose veins of the lower extremities in the system of the great saphenous vein (GSV) with class C2 of chronic venous insufficiency (CVI) — CEAP class C2. Materials and methods: 455 patients (455 limbs) with CEAP class C2. Group 1 (n = 154) received stripping + minimally invasive phlebectomy; Group 2 — endovenous laser ablation (EVLA) of GSV trunk + sclerotherapy of varicose veins; 3 group (n = 150) — radiofrequency ablation (RFA) of the GSV + sclerotherapy. All patients were united by a single tactical solution — the elimination of pathological vertical reflux in GSV. In each group, patients were with similar hemodynamic profile were selected (Group 1 = 63; Group 2 = 61; Group 3 = 61). The course of the postoperative period (from 2 days to 2 months) was compared for pain (visual analog scale — VAS), clinical symptoms of chronic venous insufficiency, degree of satisfaction (Darvall questionnaire), and duration of disability. Statistical processing was carried out using Excel programs for Windows XP, MedCalc® (version 11.4.2.0., Mariakerke, Belgium). Results: Postoperative pain is more pronounced (during day 1 for Group 1–4.0, Group 2–3.0, Group 3–2.0) and more prolonged (up to 4 days) after open surgeries (p < 0.05). The dynamics of the clinical symptoms of CVI (including varicose syndrome and use of compression therapy) could not be fully evaluated in connection with the ongoing sclerotherapy procedures for patients of Groups 2 and 3. Satisfaction of patients with aesthetic aspects was higher than expected in all groups. Reliable statistical differences proved decrease in days of disability (Group 1–14; Group 2–4; Group 3–3) and earlier return to physical activities and work in patients after thermal ablation in comparison with phlebectomy. Conclusion: The study shows that all three methods for eliminating vertical reflux in the GSV can be proposed for a large category of patients with CEAP of class C3 and C2. Medical and social rehabilitation of patients using endovascular thermal ablation technologies proceeds faster, which is beneficial both for the patients and for society.

Analysis of the quality of early diagnostics of cardiovascular diseases in students of educational institutions of Khabarovsk (according to the data of preventive examinations)

2020 ◽  
pp. 13-16
Keyword(s):  
Blood Pressure ◽  
Cardiovascular Diseases ◽  
Sinus Tachycardia ◽  
Blood Pressure Level ◽  
Educational Institutions ◽  
Conduction Disturbances ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

To identify the prevalence of early pathology of cardiovascular diseases, a survey of 400 200 girls) in the age group 15 and 17 years old was conducted as a part of routine medical of the level of blood pressure (BP) was carried out, with the calculation of the average level pressure on the basis of three separate measurements estimated by percentile tables for a registration of a standard resting ECG in 12 leads. According to the results of the survey, into 3 groups: with an increase in blood pressure above 95 ‰ (group 1 – 16 people), which recorded in males (p<0,05); Group 2 (67 people) – adolescents with a normal blood pressure level and group 3 of adolescents with a decrease in blood pressure below 5 ‰ changes in the form of rhythm and conduction disturbances were noted in almost every a predominance of sinus tachycardia in the first group. In the third group of adolescents, form of ectopic rhythm and pacemaker migration were significantly more frequently only 78 % of adolescents were referred for consultation and in-depth examination by a pediatric cardiologist.

Does Perioperative Hemoglobin A1c Level Affect the Incidence, Pattern and Mortality of Lower Extremity Amputation?

2019 ◽  
Vol 17 (4) ◽  
pp. 354-364
Author(s):  
Hassan Al-Thani ◽  
Moamena El-Matbouly ◽  
Maryam Al-Sulaiti ◽  
Noora Al-Thani ◽  
Mohammad Asim ◽  
...  
Keyword(s):  
Glycemic Control ◽  
Lower Extremity ◽  
Hazard Ratio ◽  
Lower Extremity Amputation ◽  
Group 4 ◽  
Group 3 ◽  
Group 5 ◽  
Group 2 ◽  
Extremity Amputation ◽  
Group 1

Background: We hypothesized that perioperative HbA1c influenced the pattern and outcomes of Lower Extremity Amputation (LEA). Methods: A retrospective analysis was conducted for all patients who underwent LEA between 2000 and 2013. Patients were categorized into 5 groups according to their perioperative HbA1c values [Group 1 (<6.5%), Group 2 (6.5-7.4%), Group 3 (7.5-8.4%), Group 4 (8.5-9.4%) and Group 5 (≥9.5%)]. We identified 848 patients with LEA; perioperative HbA1c levels were available in 547 cases (Group 1: 18.8%, Group 2: 17.7%, Group 3: 15.0%, Group 4: 13.5% and Group 5: 34.9%). Major amputation was performed in 35%, 32%, 22%, 10.8% and 13.6%, respectively. Results: The overall mortality was 36.5%; of that one quarter occurred during the index hospitalization. Mortality was higher in Group 1 (57.4%) compared with Groups 2-5 (46.9%, 38.3%, 36.1% and 31.2%, respectively, p=0.001). Cox regression analysis showed that poor glycemic control (Group 4 and 5) had lower risk of mortality post-LEA [hazard ratio 0.57 (95% CI 0.35-0.93) and hazard ratio 0.46 (95% CI 0.31-0.69)]; this mortality risk persisted even after adjustment for age and sex but was statistically insignificant. The rate of LEA was greater among poor glycemic control patients; however, the mortality was higher among patients with tight control. Conclusion: The effects of HbA1c on the immediate and long-term LEA outcomes and its therapeutic implications need further investigation.

Cholinesterase Activities and Oxidative Stress in Cattle Experimentally Exposed to Nitrate/Nitrite in Cultivated Pasture with Different Fertilization Schemes

2018 ◽  
Vol 46 (1) ◽  
Author(s):  
Ricardo Christ ◽  
Aleksandro Schafer Da Silva ◽  
Mateus Eloir Grabriel ◽  
Luan Cleber Henker ◽  
Renan Augusto Cechin ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Enzyme Activity ◽  
Cholinesterase Activity ◽  
Blood Samples ◽  
Group 3 ◽  
Cholinesterase Activities ◽  
Group 2 ◽  
Nitrate And Nitrite ◽  
And Oxidative Stress ◽  
Group 1

  Background: Nitrate and nitrite poisoning is associated with pasture intake that has high nitrate levels and leads to acute methemoglobinemia. Pasture may accumulate nitrate under certain conditions, such as excessively fertilized soil or en­vironmental conditions that enhance the N absorption (rain preceded by a period of drought). After ingestion of plants, this substrate reaches the rumen and, in physiological conditions, is reduced to nitrite and afterward to ammonia. The aim of this study was to evaluate changes in cholinesterase activities and oxidative stress caused by subclinical poisoning for nitrate and nitrite in cattle fed with Pennisetum glaucum in three different fertilization schemes. Materials, Methods & Results: In order to perform the experimental poisoning, the pasture was cultivated in three dif­ferent paddocks: with nitrogen topdressing (urea; group 1), organic fertilizer (group 2) or without fertilizer (group 3; control). Nitrate accumulation in forage was evaluated by the diphenylamine test. After food fasting of 12 h, nine bovine were randomly allocated to one of the experimental groups and fed with fresh forage (ad libitum) from respective pad­dock. In different time points from beginning of pasture intake (0, 2, 4, 6 and 9 h) heart rate and respiratory frequency were assessed, as well as mucous membrane color and behavioral changes. Blood samples from jugular vein into vials with and without anticoagulant were collected. From blood samples, serum nitrite levels, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzyme activity were evaluated, as well as oxidative stress through the following param­eters: levels of nitrate/nitrite (NOx), thiobarbituric acid reactive substances (TBARS) and reactive oxygen species (ROS), beyond the antioxidant system by enzyme activity measurement of catalase (CAT) and superoxide dismutase (SOD). The diphenylamine test was positive to group 1 and 2, so that the pasture presented 3.16 mg/kg, 2.98 mg/kg and 1.67 mg/kg of nitrate for group 1, 2 and 3, respectively. In addition, cows from group 1 demonstrated increased (P < 0.05) nitrite levels in serum, compared to other groups, and greater heart rate after 9 h (P < 0.05). The AChE and BChE activity in group 1 showed significant increase (P < 0.05) at 4 and 6 h (AChE), and 4 and 9 h (BChE) compared to group 3. Also, NOx levels were lower at 6 and 9 h (P < 0.05) and at 9 h (P < 0.05) for animals of group 1 and 2, respectively, when compared to group 3. Furthermore, in the group 1 levels of ROS and TBARS were significantly higher (P < 0.05) after 2 and 4 h, and 6 and 9 h compared to other groups, respectively. The CAT activity increased significantly (P < 0.05) with 2 and 4 h of the experiment, but on the other hand, decreased at 6 and 9 h in group 1. Nevertheless, the animals from group 2 presented only a significant reduction in this enzyme activity at 9 h. Furthermore, SOD activity was reduced in animals of groups 1 (P < 0.05) at 4, 6 and 9 h, compared to other groups. Discussion: It was concluded that the nitrate and nitrite poisoning by pasture intake cultivated and fertilized with urea leads to increased levels of serum nitrite, as well as the cholinesterase activity and causes oxidative stress in cattle. It is conjectured that the cholinesterase activity and oxidative stress may assist in understanding the pathophysiology of changes caused by poisoning.Keywords: plant toxicology, poisoning, methemoglobin, cholinergic system, oxidative stress.

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