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Migmatite-like textures in anthracite:Further evidence for low-grade metamorphic melting and resolidification in high-rank coals

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Geoscience Frontiers 2021年第3期12卷 428-436页

作者： james C.Hower Susan M.Rimmer Maria Mastalerz Nicola j.Wagner University of Kentucky Center for Applied Energy Research 2540 Research Park DriveLexingtonKY 40511USA School of Earth Systems and Sustainability Southern Illinois University CarbondaleCarbondaleIL 62901USA Indiana Geological&Water Survey Indiana UniversityBloomingtonIN 47405USA Department of Geology University of JohannesburgJohannesburgSouth Africa

Previous studies demonstrated that melting,initiated by supercritical fluids in the 375-400℃range,occurred as part of anthracite metamorphism in the Appalachian *** on the known behavior of vitrinite at high temperatures and,to a lesser extent,at high pressures,it was determined that the duration of the heating,melting,and resolidification event was about 1 *** the current study,featureless vitrinite within banded maceral assemblages demonstratesthe intimate association of melted and resolidified vitrinite with anthracite-rank *** analogy with metamorphosed inorganic rocks,such associations represent diadysites and embrechites,i.e.,cross-cutting and layered migmatites,*** though the temperature of formation of the anthracite structures is several hundred℃lower than that seen in metamorphosed inorganic rocks,anthracites are metamorphic rocks and the nomenclature for metamorphic rocks may be appropriate for coal.

关键词： Igneous Metamorphic texture Pennsylvania Mesozoic basins South Africa

Potassium Depletion Stimulates Beta-Subunit of Colonic H<sup>+</sup>-K<sup>+</sup>-ATPase in Mice

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International j.urnal of Clinical Medicine 2013年第5期4卷 244-250页

作者： Guoj.n Wei james j. Ravellette Suguru Nakamura Department of Biological Sciences College of Science Engineering and Technology Murray State University Murray USA

H+-K+-ATPase (HKA) is composed of two different subunits: an alpha and a beta subunit. Previous studies have shown that in the kidney gastric HKA (HKA alpha 1) predominates under normal dietary conditions while colonic HKA (HKA alpha 2) predominates under potassium depleted conditions [1]. The purpose of the current study was to elucidate the association between the beta and different alpha subunits from stomach, colon and kidney under normal and potassium depleted conditions. Black Swiss mice were fed a potassium-free diet for 2 weeks, beta subunit expression of HKA in stomach mucosae, colon mucosae and renal outer medulla was examined and compared between normal diet and potassium depleted diet. In wild type (WT) mice, the concentrations of the beta subunit under potassium deficient conditions were found significantly increased compared with normal dietary conditions in colon mucosae (8.27 ± 0.73 vs 6.62 ± 0.55 μg/μl, n = 7, p = 0.0416), whereas in cHKA (HKA alpha 2) mice colon mucosae, the concentrations of the beta subunit were statistically the same (5.05 ± 0.31 vs 4.76 ± 0.37 μg/μl, n = 13, p = 0.2833), and the concentration of the beta subunit stayed the same in renal outer medulla and stomach mucosae as well. The data indicate that potassium deficiency results in a significant increase in the levels of HKA beta subunit concentration in the colonic tissue of WT mice. The results indicate that the HKA beta subunit associates with the cHKA (HKA alpha 2) in order to mediate bicarbonate reabsorption under potassium depletion (hypokalemia)

关键词： H+-K+-ATPase (HKA) Knockout Mice (KO) Wild-Type Mice (WT) Gastric H+-K+-ATPase (gHKA) Colonic H+-K+-ATPase (cHKA) Outer Medullary Collecting Duct (OMCD)

Active Management of Plant Canopy Temperature as a Tool for Modifying Plant Metabolic Activity

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American j.urnal of Plant Sciences 2015年第1期6卷 249-259页

作者： james R. Mahan j.hn j. Burke USDA/ARS Plant Stress and Water Conservation Laboratory Lubbock Texas USA

The relationship between a plant and its thermal environment is a maj.r determiner of its growth and development. Since plants grow and develop within continuously variable thermal environments, they are subj.cted to continuous thermal variation over their life cycle. Transpiration serves to uncouple the temperature of the plant from that of its environment in a manner that reduces the occurrence of high temperature stresses that can limit plant performance. In some agriculturally important plants, there are desirable metabolic outcomes that are associated with specific stress events (e.g. wine grapes). In these plants it is often desirable to induce temperature and water stresses of known magnitude and duration at specific points in the growing season. In this study we used a computer-controlled irrigation system that used cotton canopy temperature to control irrigation in greenhouse-grown plants over a 10-day period. The system was designed to irrigate in a manner that altered the canopy temperature relative to specific temperature thresholds (28°C, 30°C, 32°C and 34°C). The results demonstrate that automated irrigation management based on canopy temperature is capable of altering the temporal pattern of canopy temperature in a desired manner using a feed-back loop. Potential limitations on this action are related to the range of air temperatures, radiation and humidity within the environment.

关键词： Irrigation Optimum Temperature Canopy Temperature

Surgical Treatment of Penile Deformity Due to Curvature Using a Subcutaneous Soft Silicone Implant: Case Report

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Open j.urnal of Urology 2014年第7期4卷 91-97页

作者： james j. Elist Vaheh Shirvanian Gottfried Lemperle Cedars Sinai Medical Center Los Angeles CA USA Division of Plastic Surgery University of California San Diego San Diego CA USA j.hann Wolfgang Goethe University Frankfurt am Main Germany

Introduction: Congenital and acquired penile curvature has a negative impact on penile aesthetics, sexual capabilities, and male psychology. Surgical procedures yield satisfactory correction of curvature, but are usually associated with penile shortening and palpable suture material and nodules under the skin, resulting in patient dissatisfaction. Aims: To present a novel technique using a subcutaneous soft silicone implant for surgical treatment of penile soft tissue deformities with curvature, with prevention of surgery-associated penile shortening and subcutaneous “bumps”, and with additional gains in overall penile length and girth. Method: 3 patients who complained about congenital, post-traumatic, and post-penile surgery associated penile curvature, with concerns about their penile aesthetics and associated negative psychosocial effects, were treated with the insertion of a subcutaneous soft silicone penile implant. Results: During a follow up period of 2 - 12 months (mean: 6.7 ± 3.6 months) all three patients expressed obj.ctive and subj.ctive satisfaction regarding the corrective results of the surgery. Penile length and girth measurements during follow-up showed a mean increase in length of 4.3 cm (±1.4 cm) and a mean increase in girth of 3.0 cm (±1.0 cm). Conclusion: The insertion of the subcutaneous soft silicone implant in addition to corporeal fibrotic tissue removal in patients with congenital or acquired penile curvature is an effective option that provides the patient with aesthetic improvements by correcting penile deviation, preventing post-surgical subcutaneous nodule formation that results from the technique and suture material used, and adding penile length and girth. Further prospective studies are required to validate our initial experience.

关键词： Penile Curvature Peyronie’s Disease Penile Prosthesis Penile Shortening Penile Length Penile Girth Penile Augmentation Subcutaneous Soft Silicone Implant Elist Silicone Implant

Alternative Methods for Analysis of Cyanobacterial Populations in Drinking Water Supplies: Fluorometric and Toxicological Applications Using Phycocyanin

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j.urnal of Water Resource and Protection 2018年第8期10卷 740-761页

作者： Nancy j. Leland james F. Haney Lim-Tex North Andover MA USA Department of Zoology University of New Hampshire Durham NH USA

The management of cyanobacteria and potential exposure to associated biotoxins requires the allocation of scarce resources across a range of freshwater resources within various j.risdictions. Cost effective and reliable methods for sample processing and analysis form the foundation of the protocol yielding reliable data from which to derive important decisions. In this study the utilization of new methods to collect, process and analyze samples enhanced our ability to evaluate cyanobacterial populations. Extraction of phycocyanin using the single freeze thaw method provided more accurate and precise measurements (CV 4.7% and 6.4%), offering a simple and cost-effective means to overcome the influence of morphological variability. In-vacuo concentration of samples prior to ELISA analysis provided a detection limit of 0.001 μg·L?1 MC. Fractionation of samples (?1) = ?0.279 + (1.368 ? Log PC (μg·L?1) while in an Aphanizomemon spp. dominant system Log MC (ng·L?1) = 0.385 + (0.449 ? Log PC (μg·L?1). These methods and sampling protocol could be used in other aquatic systems across a broader regional landscape to estimate the levels of microcystins.

关键词： Cyanobacteria Size Fractions Fluorometry Monitoring Phycocyanin Extraction

Chip Flood (vs) Core Flood——Assessment of Flowback and Oil Productivity in Oil-Wet Hydraulic Fractured Rocks

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Open j.urnal of Yangtze Oil and Gas 2019年第1期4卷 59-78页

作者： Srikanth Tangirala james j. Sheng j.awei Tu Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityLubbockUSA

New developments in lab technologies help us to explore problems that were less understood in the past due to the limitations and technological constraints. One such problem of assessing the formation damage created by the invasion of fracture fluid into the matrix at lab scale is the visualization of fluid saturation distributions inside the matrix. According to the current understanding, the high capillarity contrast between the fracture and the matrix creates a non-uniform saturation distribution of invaded fluid phase during flowback, with the saturations mostly concentrated at the fracture face. With the advent of microfluidics, their application has become more feasible to visually analyze the effectiveness of surfactants to mitigate the invasion-created formation damage and understand the impact of depth of invasion on the characteristics of flowback and oil productivity. Through our previous work, we have successfully demonstrated the capability of this new visualization tool in studying the factors of the presence of surfactant in the fracture fluid and its depth of invasion, to understand the flowback efficiencies and later oil productivities in oil-wet fractured formations. Since the substrate for flooding was a proxy model of an actual rock, the chip flooding results need to be validated with conventional core flooding experiments. In contemporary times, when the new advancements in technology are driving the research progress in all industries, it is mandatory to take a well informed decision by imposing a comparative check on the results with accessible conventional means, wherever possible. The success of validation of chip flooding approach with the core flooding approach in this work instates a strong belief over the application of microfluidics to pursue more research in related fields of oil recovery.

关键词： Chip Flooding Core Flooding Flowback Fracture Surfactant

Avulsion Dynamics in a River with Alternating Bedrock and Alluvial Reaches, Huron River, Northern Ohio (USA)

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Open j.urnal of Modern Hydrology 2019年第1期9卷 20-39页

作者： Mark j. Potucek james E. Evans Arizona Department of Water Resources Phoenix AZ USA Department of Geology Bowling Green State University Bowling Green OH USA

The Huron River consists of alternating bedrock reaches and alluvial reaches. Analysis of historical aerial photography from 1950-2015 reveals six maj.r channel avulsion events in the 8-km study area. These avulsions occurred in the alluvial reaches but were strongly influenced by the properties of the upstream bedrock reach (“inherited characteristics”). The bedrock reaches aligned with the azimuth of j.int sets in the underlying bedrock. One inherited characteristic in the alluvial reach downstream is that the avulsion channels diverged only slightly from the orientation of the upstream bedrock channel (range 2 °- 38 °, mean and standard deviation 12.1 °± 13.7 °). A second inherited characteristic is that avulsion channels were initiated from short distances downstream after exiting the upstream bedrock channel reach (range 62 - 266 m, mean and standard deviation 143.7 ± 71.0 m), which is a fraction of the meander wavelength (1.2 km). Field evidence shows that some avulsion channel sites were re-occupied episodically. In addition, two properties were necessary for channel avulsions: 1) avulsion events were triggered by channel-forming hydrologic events (5-year recurrence interval flows), but not every channel-forming hydrologic event resulted in an avulsion, and 2) channel sinuosity (P) increased to 1.72 - 1.77 prior to an avulsion then decreased to 1.65 - 1.70 following an avulsion, suggesting that P ≥ 1.72 is the “critical sinuosity” or triggering value for avulsions on the Huron River. In summary, for this river consisting of alternating bedrock and alluvial reaches, the bedrock reaches impose certain parameters on downstream alluvial reaches (including sediment supply, channel direction and avulsion channel position downstream after exiting a bedrock reach) while adj.stments in sinuosity and sediment storage occur in the alluvial reaches.

关键词： Avulsion Bedrock Channels Alluvial Channels Cut-Offs Historical Changes Fluvial Sediment Budgets

Assessment of the Effects of Poultry Litter on Surface Runoff Water Quality from Agricultural Lands

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j.urnal of Water Resource and Protection 2010年第5期2卷 413-423页

作者： Sudarshan K. Dutta Shreeram P. Inamdar j. Tom Sims Alyssa collins 不详

The use of pelletized poultry litter (PPL) as a substitute for inorganic fertilizers is increasingly being en-couraged in states like Delaware which have a considerable surplus of poultry litter. However, we know very little about the impacts of PPL on runoff water quality and whether it is an environmentally-sound and sus-tainable alternative to inorganic fertilizer. To address these questions we compared the exports of nutrients (NH4-N, NO3-N and PO4-P) and trace elements (As, Cu, and Zn) in surface runoff from agricultural plots receiving PPL, raw poultry litter (RPL), urea and no-fertilizer (control) treatments. The study was conducted on agricultural land located in Middletown, Delaware with corn as the cover crop. The experimental plots were 5 m wide and 12 m long with reduced tillage and no-tillage management practices. Sampling was con-ducted for six natural rainfall events from April through August 2008. Nutrient (NH4-N, NO3-N and PO4-P) exports from plots receiving PPL were less than those with urea or raw litter applications. While exports of trace elements from the PPL treatment exceeded those from urea, they were much lower than the corre-sponding exports from the RPL treatments. Mass exports of nutrients and trace elements were correlated with event size (rainfall amount) but were not correlated with timing of event (days since litter application). Results from this study suggest that the use of PPL in combination with no-tillage may provide an environ-mentally safe alternative to synthetic fertilizers.

关键词： Poultry Litter Surface Runoff Water Quality Tillage Best Management Practices Nutrients Trace Elements

A Cluster Analysis of Lifestyle and Health Habits of Youth from Two Geographically and Culturally Diverse Countries

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Open j.urnal of Preventive Medicine 2014年第4期4卷 193-203页

作者： Yahya Al-Nakeeb Lorna j. Dodd Mark Lyons Peter collins Anwar Al-Nuaim College of Education Qatar University Doha Qatar Department of Physical Education King Faisal University Dammam Saudi Arabia Department of Psychology and Counselling Newman University Birmingham UK Faculty of Education and Health Sciences Univer-sity of Limerick Limerick Ireland School of Human Sciences Newman University Birmingham UK

Obj.ctives: Obesity is a leading risk factor for global mortality, promoted by poor dietary habits and sedentary behaviour. This study explores the clustering and differences in dietary habits, body mass index (BMI) and physical activity (PA) amongst youth from United Kingdom (UK) and Saudi Arabia (SA). Methods: 2290 males and females aged 15-17 years completed a self-report questionnaire and an obj.ctive measure of BMI. Results: Youth from SA had a higher prevalence of overweight/obesity and lower levels of PA than youth from the UK. Males were more physically active than females across both countries. Three clusters were identified: a “high risk” cluster with least healthy dietary habits, low PA and high BMI;a “moderate cluster” with moderate healthy dietary habits, PA and BMI;a “low risk” cluster with healthiest dietary habits, greatest PA and the lowest BMI compared to the other clusters. There were more SA youth in the high and moderate risk clusters compared to UK youth. Conclusions: Exploring cross-cultural and demographic characteristics of youth enables the identification of similarities and differences that might lead to the development of universal intervention strategies.

关键词： Clustering Risk Factors Youth Diet Physical Activity Body Mass Index