scholarly journals Role of persistent low-level clouds in mitigating air quality impacts of wintertime cold pool conditions

2017 ◽  
Vol 154 ◽  
pp. 236-246 ◽  
Author(s):  
Timothy M. VanReken ◽  
Ranil S. Dhammapala ◽  
B. Thomas Jobson ◽  
Courtney L. Bottenus ◽  
Graham S. VanderSchelden ◽  
...  
Keyword(s):  
Air Quality ◽  
Cold Pool ◽  
Low Level

scholarly journals Influence of Low-Level Thermodynamic Structure on the Downdraft Properties of Simulated Supercells

2012 ◽  
Vol 140 (8) ◽  
pp. 2575-2589 ◽  
Author(s):  
Jason Naylor ◽  
Mark A. Askelson ◽  
Matthew S. Gilmore
Keyword(s):  
Potential Temperature ◽  
Weather Research And Forecasting ◽  
Cold Pool ◽  
Forecasting Model ◽  
Mixing Ratio ◽  
Near Surface ◽  
Thermodynamic Structure ◽  
Low Level ◽  
Capping Inversion

Abstract Idealized simulations using the Weather Research and Forecasting Model (WRF) were performed to examine the role of capping inversions on the near-surface thermodynamic structure of outflow from simulated supercells. Two simulations were performed: one with the traditional noncapped Weisman and Klemp (WK) analytic sounding and the second with a WK sounding modified to contain a capping inversion. Both sounding environments favor splitting storms and a right-moving supercell by 90 min into the simulation. These two supercell simulations evolve in a qualitatively similar fashion, with both storms exhibiting large, quasi-steady updrafts, hook-shaped appendages in the precipitation mixing ratio field, and prominent localized downdrafts. Results show that the supercell simulated in the capped environment has a surface cold pool with larger values of pseudoequivalent potential temperature (θep) than the cold pool of the supercell produced in the noncapped simulation. Parcels in the surface cold pool of the supercell produced in the capped sounding simulation have a lower origin height than those in the surface cold pool of the supercell produced in the noncapped simulation for all times. Although θep values in the surface cold pool are primarily associated with the origin height of downdraft parcels and the environmental θep at that level, it is shown that nonconservation of θep primarily associated with hydrometeor melting can decrease θep values of downdraft parcels as they descend by several degrees.

Tryptophan-Niacin Metabolism in Rat with Puromycin Aminonucleoside-Induced Nephrosis

2006 ◽  
Vol 76 (1) ◽  
pp. 28-33 ◽  
Author(s):  
Yukari Egashira ◽  
Shin Nagaki ◽  
Hiroo Sanada
Keyword(s):  
Body Weight ◽  
Urinary Excretion ◽  
Enzyme Activities ◽  
Treated Group ◽  
Control Group ◽  
Puromycin Aminonucleoside ◽  
Low Level ◽  
Key Enzyme

We investigated the change of tryptophan-niacin metabolism in rats with puromycin aminonucleoside PAN-induced nephrosis, the mechanisms responsible for their change of urinary excretion of nicotinamide and its metabolites, and the role of the kidney in tryptophan-niacin conversion. PAN-treated rats were intraperitoneally injected once with a 1.0% (w/v) solution of PAN at a dose of 100 mg/kg body weight. The collection of 24-hour urine was conducted 8 days after PAN injection. Daily urinary excretion of nicotinamide and its metabolites, liver and blood NAD, and key enzyme activities of tryptophan-niacin metabolism were determined. In PAN-treated rats, the sum of urinary excretion of nicotinamide and its metabolites was significantly lower compared with controls. The kidneyα-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD) activity in the PAN-treated group was significantly decreased by 50%, compared with the control group. Although kidney ACMSD activity was reduced, the conversion of tryptophan to niacin tended to be lower in the PAN-treated rats. A decrease in urinary excretion of niacin and the conversion of tryptophan to niacin in nephrotic rats may contribute to a low level of blood tryptophan. The role of kidney ACMSD activity may be minimal concerning tryptophan-niacin conversion under this experimental condition.

ROLE OF LIPID PROFILE IN OVARIAN CARCINOMA PATIENTS

2019 ◽  
Vol 3 (8) ◽  
Author(s):  
Dr. Manisha ◽  
Dr. Ruchi Jindal
Keyword(s):  
Ovarian Cancer ◽  
Lipid Profile ◽  
Cancer Patients ◽  
Ovarian Tumor ◽  
Ovarian Cancer Risk ◽  
Low Level ◽  
Medical College ◽  
Group I ◽  
History Of

Background: The term "ovarian cancer" includes several different types of cancer that  arise from cells of the ovary, most commonly, tumors arise from the epithelium or lining cells of the ovary.  Ovarian cancer risk is positively associated with higher consumption of dietary cholesterol and eggs, and inversely associated with a higher intake of vegetables. High consumption of fats may increase circulating estrogen levels, thus increasing the possibility of cell damage and proliferation that is responsible for cancerous growth. Material & Methods: The present study was conducted at Geetanjali Medical College and Hospital, Udaipur (Rajasthan). Total  100 cases (females) attending the obstetrics and gynecology department for some gynecological and other problem  were selected for this study between the age of 40-60 years, who were attending cancer centre at GEETANJALI MEDICAL COLLEGE AND  HOSPITAL, Udaipur (Rajasthan).                GROUP I: - It consisted of healthy females control subjects (n=50) .By routine examination and tests, we ensured that all the subjects were healthy and there were no signs and symptoms or history of ovarian tumor and diseases GROUP II: - It consisted of ovarian cancer females subjects (n=50) with a history of ovarian tumor. Results:   Higher level of cholesterol, LDL, VLDL and low level of HDL are found in ovarian cancer patients. Conclusion: The present study we highlights the importance and role of serum lipid profile in diagnosis, prognosis and recurrence of the disease. The study shows that serum level of cholesterol, LDL, VLDL was elevated in  patients of ovarian cancer while low level of HDL are found in ovarian cancer patients. Key words: lipid profile, ovarian cancer.

scholarly journals From Black to Blue Skies: Civil Society Perceptions of Air Pollution in Shanghai

2021 ◽  
pp. 1-22
Author(s):  
Amanda K. Winter ◽  
Huong Le ◽  
Simon Roberts
Keyword(s):  
Air Pollution ◽  
Civil Society ◽  
Air Quality ◽  
Qualitative Case Study ◽  
Field Research ◽  
Ecological Civilization ◽  
Civil Society Participation ◽  
Quality Indexes

Abstract This paper explores the perception and politics of air pollution in Shanghai. We present a qualitative case study based on a literature review of relevant policies and research on civil society and air pollution, in dialogue with air quality indexes and field research data. We engage with the concept of China's authoritarian environmentalism and the political context of ecological civilization. We find that discussions about air pollution are often placed in a frame that is both locally temporal (environment) and internationally developmentalist (economy). We raise questions from an example of three applications with different presentations of air quality index measures for the same time and place. This example and frame highlight the central role and connection between technology, data and evidence, and pollution visibility in the case of the perception of air pollution. Our findings then point to two gaps in authoritarian environmentalism research, revealing a need to better understand (1) the role of technology within this governance context, and (2) the tensions created from this non-participatory approach with ecological civilization, which calls for civil society participation.

The Role of Equatorial Rossby Waves in Tropical Cyclogenesis. Part I: Idealized Numerical Simulations in an Initially Quiescent Background Environment

2010 ◽  
Vol 138 (4) ◽  
pp. 1368-1382 ◽  
Author(s):  
Jeffrey S. Gall ◽  
William M. Frank ◽  
Matthew C. Wheeler
Keyword(s):  
Tropical Cyclone ◽  
Large Scale ◽  
Phase Speed ◽  
Tropical Cyclogenesis ◽  
Initial Amplitude ◽  
Low Level ◽  
Wave Simulation ◽  
Horizontal Momentum ◽  
Good Agreement

Abstract This two-part series of papers examines the role of equatorial Rossby (ER) waves in tropical cyclone (TC) genesis. To do this, a unique initialization procedure is utilized to insert n = 1 ER waves into a numerical model that is able to faithfully produce TCs. In this first paper, experiments are carried out under the idealized condition of an initially quiescent background environment. Experiments are performed with varying initial wave amplitudes and with and without diabatic effects. This is done to both investigate how the properties of the simulated ER waves compare to the properties of observed ER waves and explore the role of the initial perturbation strength of the ER wave on genesis. In the dry, frictionless ER wave simulation the phase speed is slightly slower than the phase speed predicted from linear theory. Large-scale ascent develops in the region of low-level poleward flow, which is in good agreement with the theoretical structure of an n = 1 ER wave. The structures and phase speeds of the simulated full-physics ER waves are in good agreement with recent observational studies of ER waves that utilize wavenumber–frequency filtering techniques. Convection occurs primarily in the eastern half of the cyclonic gyre, as do the most favorable conditions for TC genesis. This region features sufficient midlevel moisture, anomalously strong low-level cyclonic vorticity, enhanced convection, and minimal vertical shear. Tropical cyclogenesis occurs only in the largest initial-amplitude ER wave simulation. The formation of the initial tropical disturbance that ultimately develops into a tropical cyclone is shown to be sensitive to the nonlinear horizontal momentum advection terms. When the largest initial-amplitude simulation is rerun with the nonlinear horizontal momentum advection terms turned off, tropical cyclogenesis does not occur, but the convectively coupled ER wave retains the properties of the ER wave observed in the smaller initial-amplitude simulations. It is shown that this isolated wave-only genesis process only occurs for strong ER waves in which the nonlinear advection is large. Part II will look at the more realistic case of ER wave–related genesis in which a sufficiently intense ER wave interacts with favorable large-scale flow features.

Role of low-level jets and boundary-layer properties on the NBL budget technique

2005 ◽  
Vol 135 (1-4) ◽  
pp. 35-43 ◽  
Author(s):  
N. Mathieu ◽  
I.B. Strachan ◽  
M.Y. Leclerc ◽  
A. Karipot ◽  
E. Pattey
Keyword(s):  
Boundary Layer ◽  
Low Level ◽  
Low Level Jets

The Role of Midtropospheric Winds in the Evolution and Maintenance of Low-Level Mesocyclones

1994 ◽  
Vol 122 (1) ◽  
pp. 126-136 ◽  
Author(s):  
Harold E. Brooks ◽  
Charles A. Doswell ◽  
Robert B. Wilhelmson
Keyword(s):  
Low Level
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