gaseous exchange
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Author(s):  
Boas Malagat ◽  
Kari Iamba

A good sowing media ensures better anchorage of plants, provides a reservoir of  nutrients and water, and enhance gaseous exchange with the atmosphere. Balsa (Ochroma lagopus Swartz); Vimmy variety, has proven its versatility in producing some of the best phenotypic characteristics such as higher jorquette height, less branching and high log volumes. This experiment was carried out using a combination of three different local materials; local garden soil, pumice soil and sawdust but in different combination ratios aimed to investigate the best combinations. Six treatments were tested: T1= Pure Garden soil, T2= Pumice, T3= Control (75% large coarse sawdust, 25% pure garden soil), T4= Pure Sawdust, T5= 50% medium coarse sawdust, 50% pure soil, and, T6= 33% medium coarse sawdust, 33% Pumice, 33% Pure garden Soil. The daily average germination count in Treatment 5 (50% medium coarse sawdust & 50% pure soil) produced constant germinations from day fifteen (15) to day twenty one (21). Treatments 1, 2, 3, 4 and 6 showed high variations in their daily average germination for the same period but did not produce a constant supply of germinations. Treatment 5 had the highest emergence rate index (ERI=71.76) followed by treatment 1 (ERI=66.59).  Treatment 4 had the third highest seedling emergence (ERI=63.74) followed by treatment 3 (ERI=59.37), treatment 6 (ERI=57.22) and treatment 2 (ERI=53.81) at the lowest continuum. Substrates containing 50% soil and 50% medium coarse sawdust are regarded as better sowing media for O. lagopus seedlings.


2021 ◽  
Vol 22 ◽  
Author(s):  
Hitesh Chopra ◽  
Sandeep Kumar ◽  
Inderbir Singh

: Wound healing is the complex and a never-ending process that involves numerous mediators, enzymatic cascades that are directly or indirectly involved in the mechanism. So, it becomes necessary to closely examine critical factors such as gaseous exchange, a moist environment, anti-microbial activity, and exudation liquids' absorption while designing wound dressings. There is a heap of wound dressings available for human use, but they all are way apart from the ideal dressing. Use of biopolymers may be a solution to tackle the difficulties such as combining with growth factors and cells that can trigger the wound healing. This article reviews such therapies for wound healing application.


‘Respiratory and cardiovascular systems’ begins with the anatomy of the thoracic cavity, including the lungs, skeletal tissue, and soft tissue, before consideration of the two main physiological components of the thorax: the pulmonary and cardiovascular systems. The main structures of the pulmonary system are discussed (pleura and pleural cavities, the upper and lower airways), together with respiratory mechanics, the principles of gaseous exchange and gas transport in the blood, the relationships between ventilation and perfusion, and the regulation of breathing. Major respiratory conditions and diseases are also covered, such as cystic fibrosis, pulmonary embolism, asthma, and the effect of altitude. The cardiovascular system topics includes blood physiology (haematology and haemostasis) and the heart in terms of anatomy, its function as a pump, and the nature of the heart as an electrical tissue (the electrocardiogram). The function of the heart is discussed, including during exercise and in diseases such as heart failure and hypertension.


Author(s):  
Terry Robinson ◽  
Jane Scullion

Up to an altitude of approximately 30,000 feet, the composition of the gas in the air we breathe remains almost constant. Atmospheric pressure decreases exponentially with altitude. This means that although the gas composition at high altitude remains the same, the air is less dense, resulting in less available oxygen for gaseous exchange. Hypobaric hypoxia therefore develops as a result of low atmospheric atmosphere. This chapter discusses the effects of flying, high altitudes, and diving on respiration. It starts by describing atmospheric pressure and altitude, the then-acute mountain sickness (AMS) and its management. Flying with lung disease is covered, alongside fitness to fly, the use of in-flight oxygen, and general precautions to take. Diving, diving-related illnesses, and practising the sport with pre-existing lung conditions are also included.


2020 ◽  
Vol 12 (24) ◽  
pp. 10649
Author(s):  
Zanib Nazar ◽  
Nudrat Aisha Akram ◽  
Muhammad Hamzah Saleem ◽  
Muhammad Ashraf ◽  
Shakeel Ahmed ◽  
...  

Several inorganic and organic compounds including glycine betaine (GB) are presently being used as an exogenous application to enhance tolerance in plants to different environmental stresses. The current study assessed to what extent exogenously applied GB could improve the gaseous exchange capacity and primary and secondary metabolites in two accessions (16178 and 16180) of safflower (Carthamus tinctorius L.) plants under drought stress. Three-week-old plants of both safflower accessions were subjected to well-watered (control) or water-deficit conditions (60% field capacity (FC)). Three levels of GB (control, 50 mM and 100 mM) were sprayed to the foliage of the control and stressed plants after one month of drought application. After two weeks of foliar application of GB, gas exchange characteristics and other biochemical parameters were determined. The results showed that water deficiency markedly suppressed plant biomass, chlorophyll contents, photosynthesis rate (A), water use efficiency (A/E), stomatal conductance (gs) and relative water contents (RWC) of both accessions of safflower, while it enhanced the levels of osmolytes (GB and proline), hydrogen peroxide (H2O2) and total phenolics. Foliar application of GB was effective in enhancing the plant biomass, chlorophyll contents, gs, sub-stomatal CO2 concentration (Ci), Ci/Ca ratio, osmolytes, H2O2, ascorbic acid (AsA), total phenolics and RWC in safflower plants under water shortage. Thus, exogenous application of GB could be used as an effective strategy to improve plant growth, photosynthetic attributes and secondary metabolites in safflower plants under water deficit conditions.


2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Philip J. Prins ◽  
Dominic P. D’Agostino ◽  
Christopher Q. Rogers ◽  
Dana L. Ault ◽  
Gary L. Welton ◽  
...  

Abstract Background Interest into the health, disease, and performance impact of exogenous ketone bodies has rapidly expanded due to their multifaceted physiological and signaling properties but limiting our understanding is the isolated analyses of individual types and dose/dosing protocols. Methods Thirteen recreational male distance runners (24.8 ± 9.6 years, 72.5 ± 8.3 kg, VO2max 60.1 ± 5.4 ml/kg/min) participated in this randomized, double-blind, crossover design study. The first two sessions consisted of a 5-km running time trial familiarization and a VO2max test. During subsequent trials, subjects were randomly assigned to one (KS1: 22.1 g) or two (KS2: 44.2 g) doses of beta-hydroxybutyrate (βHB) and medium chain triglycerides (MCTs) or flavor matched placebo (PLA). Blood R-βHB, glucose, and lactate concentrations were measured at baseline (0-min), post-supplement (30 and 60 min), post-exercise (+ 0 min, + 15 min). Time, heart rate (HR), rating of perceived exertion (RPE), affect, respiratory exchange ratio, oxygen consumption (VO2), carbon dioxide production, and ventilation were measured during exercise. Cognitive performance was evaluated prior to and post-exercise. Results KS significantly increased R-βHB, with more potent and prolonged elevations in KS2, illustrating an administrative and dosing effect. R-βHB was significantly decreased in KS1 compared to KS2 illustrating a dosing and exercise interaction effect. Blood glucose elevated post-exercise but was unchanged across groups. Blood lactate significantly increased post-exercise but was augmented by KS administration. Gaseous exchange, respiration, HR, affect, RPE, and exercise performance was unaltered with KS administration. However, clear responders and none-responders were indicated. KS2 significantly augmented cognitive function in pre-exercise conditions, while exercise increased cognitive performance for KS1 and PLA to pre-exercise KS2 levels. Conclusion Novel βHB + MCT formulation had a dosing effect on R-βHB and cognitive performance, an administrative response on blood lactate, while not influencing gaseous exchange, respiration, HR, affect, RPE, and exercise performance.


2020 ◽  
Vol 2 (8) ◽  
pp. 4-16
Author(s):  
Humphrey Simukokoa ◽  

The world is currently faced with a very serious crisis to deal with the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2 or Covid-19) pandemic which started in Wuhan, China in December 2019 and has since spread throughout the world, wreaking havoc in many countries. Several efforts are being made to control the spread of the disease around the world and to find a cure or vaccine. As researchers frantically endeavor to identify remedies for covid19, there is the need to identify therapies that offer the quickest, safest actions and remedies that are relatively cheap. We propose the use of aerosolized inhalation antibody conjugated nanoparticles for the treatment of covid-19. It is hypothesized in this proposal that the conjugation of nanoparticles with antibodies and delivering the antibody-nanoparticle conjugate as an aerosol via the respiratory tract would provide the quickest and possibly more efficient and relatively cheap remedy against covid-19. The advantage of the inhalation route for delivering antibody conjugated nanoparticles is that since the medication is delivered directly to the affected site, higher doses will be delivered to the site with reduced systemic toxicity and reduced adverse effects on gaseous exchange. Our hypothesis is based on the current knowledge and observations in the areas of monoclonal antibody technology, advances in nanotechnology and Nano medicine as well as advances in inhalation therapeutics.


2020 ◽  
Author(s):  
Philip J. Prins ◽  
Dominic P. D’Agostino ◽  
Christopher Q. Rogers ◽  
Dana L. Ault ◽  
Gary L. Welton ◽  
...  

Abstract Background: Interest into the health, disease, and performance impact of exogenous ketone bodies has rapidly expanded due to their multifaceted physiological and signaling properties but limiting our understanding is the isolated analyses of individual types and dose/dosing protocols. Methods: Thirteen recreational male distance runners (24.8±9.6y, 72.5±8.3kg, VO2max 60.1±5.4ml/kg/min) participated in this randomized, double-blind, crossover design study. The first two sessions consisted of a 5-km running time trial (TT) familiarization and a VO2max test. During subsequent trials, subjects were randomly assigned to one (KS1:22.1g) or two (KS2:44.2g) doses of beta-hydroxybutyrate (βHB) and medium chain triglycerides (MCTs) or flavor matched placebo (PLA). Blood R-βHB, glucose, and lactate concentrations were measured at baseline (0-min), post-supplement (30 & 60mins), post-exercise (+0min, +15mins). Time, heart rate (HR), rating of perceived exertion (RPE), affect, respiratory exchange ratio (RER), oxygen consumption (VO2), carbon dioxide production (VCO2), and ventilation (VE) were measured during exercise. Cognitive performance was evaluated prior to and post-exercise. Results: KS significantly increased R-βHB, with more potent and prolonged elevations in KS2, illustrating an administrative and dosing effect. R-βHB was significantly decreased in KS1 compared to KS2 illustrating a dosing and exercise interaction effect. Blood glucose elevated post-exercise but was unchanged across groups. Blood lactate significantly increased post-exercise but was augmented by KS administration. Gaseous exchange, respiration, HR , affect, RPE, and exercise performance was unaltered with KS administration. However, clear responders and none-responders were indicated. KS2 significantly augmented cognitive function in pre-exercise conditions, while exercise increased cognitive performance for KS1 and PLA to pre-exercise KS2 levels. Conclusion: Novel βHB+MCT formulation had a dosing effect on R-βHB and cognitive performance, an administrative response on blood lactate, while not influencing gaseous exchange, respiration, HR, affect, RPE, and exercise performance.


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