scholarly journals Regional venous–arterial CO2 to arterial–venous O2 content difference ratio in experimental circulatory shock and hypoxia

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Thiago Domingos Corrêa ◽  
Adriano José Pereira ◽  
Jukka Takala ◽  
Stephan Mathias Jakob
Keyword(s):  
Carbon Dioxide ◽  
Experimental Studies ◽  
Original Data ◽  
Hypoxic Injury ◽  
Content Difference ◽  
Hemodynamic Variables ◽  
Regional Hemodynamics ◽  
Independent Association ◽  
Post Hoc ◽  
Lactate Exchange

Abstract Background Venous–arterial carbon dioxide (CO2) to arterial–venous oxygen (O2) content difference ratio (Cv-aCO2/Ca-vO2) > 1 is supposed to be both sensitive and specific for anaerobic metabolism. What regional hemodynamic and metabolic parameters determine the ratio has not been clarified. Objectives To address determinants of systemic and renal, spleen, gut and liver Cv-aCO2/Ca-vO2. Methods Post hoc analysis of original data from published experimental studies aimed to address effects of different fluid resuscitation strategies on oxygen transport, lactate metabolism and organ dysfunction in fecal peritonitis and endotoxin infusion, and from animals in cardiac tamponade or hypoxic hypoxia. Systemic and regional hemodynamics, blood flow, lactate uptake, carbon dioxide and oxygen-derived variables were determined. Generalized estimating equations (GEE) were fit to assess contributors to systemic and regional Cv-aCO2/Ca-vO2. Results Median (range) of pooled systemic Cv-aCO2/Ca-vO2 in 64 pigs was 1.02 (0.02 to 3.84). While parameters reflecting regional lactate exchange were variably associated with the respective regional Cv-aCO2/Ca-vO2 ratios, only regional ratios were independently correlated with systemic ratio: renal Cv-aCO2 /Ca-vO2 (β = 0.148, 95% CI 0.062 to 0.234; p = 0.001), spleen Cv-aCO2/Ca-vO2 (β = 0.065, 95% CI 0.002 to 0.127; p = 0.042), gut Cv-aCO2/Ca-vO2 (β = 0.117, 95% CI 0.025 to 0.209; p = 0.013), liver Cv-aCO2/Ca-vO2 (β = − 0.159, 95% CI − 0.297 to − 0.022; p = 0.023), hepatosplanchnic Cv-aCO2/Ca-vO2 (β = 0.495, 95% CI 0.205 to 0.786; p = 0.001). Conclusion In a mixed set of animals in different shock forms or during hypoxic injury, hepatosplanchnic Cv-aCO2/Ca-vO2 ratio had the strongest independent association with systemic Cv-aCO2/Ca-vO2, while no independent association was demonstrated for lactate or hemodynamic variables.

Rossenbeck. On the question of the ketogenic nature of physiological acidosis of pregnancy (Mtschs. Geburtsch. Gyn. 1936, 102, 3, 129-143)

1937 ◽  
Vol 33 (5) ◽  
pp. 649-649
Author(s):  
B. Ivanov
Keyword(s):  
Carbon Dioxide ◽  
Pregnant Women ◽  
Ketone Bodies ◽  
Experimental Studies

Based on his experimental studies in healthy non-pregnant and pregnant women, a. believes that the decrease in the ability of their blood to bind carbon dioxide cannot be explained by an increase in the level of ketone bodies in the blood during pregnancy, especially in her last 3 months.

Self-gasified biosystems for enhanced oil recovery

2021 ◽  
pp. 2150274
Author(s):  
B. A. Suleimanov ◽  
S. J. Rzayeva ◽  
U. T. Akhmedova
Keyword(s):  
Carbon Dioxide ◽  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Experimental Studies ◽  
Microbial Enhanced Oil Recovery ◽  
Heterogeneous Porous Medium ◽  
Oil Displacement ◽  
Subcritical Region ◽  
Reservoir Conditions

Microbial enhanced oil recovery is considered to be one of the most promising methods of stimulating formation, contributing to a higher level of oil production from long-term fields. The injection of bioreagents into a reservoir results in the creation of oil-displacing agents along with a significant amount of gases, mainly carbon dioxide. Earlier, the authors failed to study the preparation of self-gasified biosystems and the implementation of the subcritical region (SR) under reservoir conditions. Gasified systems in the subcritical phase have better oil-displacing properties than nongasified systems. In a heterogeneous porous medium, the filtration profile of gasified liquids in the SR should be more uniform than for a degassed liquid. Based on experimental studies, the superior efficiency of oil displacement by gasified biosystems compared with degassed ones has been demonstrated. The possibility of efficient use of gasified hybrid biopolymer systems has been shown.

Forsterite reprecipitation and carbon dioxide entrapment in the lithospheric mantle during its interaction with carbonatitic melt: a case study from the Sung Valley ultramafic–alkaline–carbonatite complex, Meghalaya, NE India

2020 ◽  
pp. 1-12
Author(s):  
Shubham Choudhary ◽  
Koushik Sen ◽  
Santosh Kumar ◽  
Shruti Rana ◽  
Swakangkha Ghosh
Keyword(s):  
Carbon Dioxide ◽  
Lithospheric Mantle ◽  
Experimental Studies ◽  
Carbonatite Complex ◽  
Kerguelen Plume ◽  
Ne India ◽  
Isotopic Analyses ◽  
Oxygen Isotopic ◽  
Carbonatite Magma

Abstract Carbonatite melts derived from the mantle are enriched in CO2- and H2O-bearing fluids. This melt can metasomatize the peridotitic lithosphere and liberate a considerable amount of CO2. Experimental studies have also shown that a CO2–H2O-rich fluid can form Fe- and Mg-rich carbonate by reacting with olivine. The Sung Valley carbonatite of NE India is related to the Kerguelen plume and is characterized by rare occurrences of olivine. Our study shows that this olivine is resorbed forsterite of xenocrystic nature. This olivine bears inclusions of Fe-rich magnesite. Accessory apatite in the host carbonatite contains CO2–H2O fluid inclusions. Carbon and oxygen isotopic analyses indicate that the carbonatites are primary igneous carbonatites and are devoid of any alteration or fractionation. We envisage that the forsterite is a part of the lithospheric mantle that was reprecipitated in a carbonatite reservoir through dissolution–precipitation. Carbonation of this forsterite, during interaction between the lithospheric mantle and carbonatite melt, formed Fe-rich magnesite. CO2–H2O-rich fluid derived from the carbonatite magma and detected within accessory apatite caused this carbonation. Our study suggests that a significant amount of CO2 degassed from the mantle by carbonatitic magma can become entrapped in the lithosphere by forming Fe- and Mg-rich carbonates.

scholarly journals A Model of Brain Arteriolar Oxygen and Carbon Dioxide Transport during Anemia

1993 ◽  
Vol 13 (5) ◽  
pp. 872-880 ◽  
Author(s):  
Richard S. Schacterle ◽  
Robert J. Ribando ◽  
J. Milton Adams
Keyword(s):  
Carbon Dioxide ◽  
Mathematical Model ◽  
Blood Flow ◽  
Tissue Oxygenation ◽  
Normal Values ◽  
Experimental Studies ◽  
Limited Information ◽  
Carbon Dioxide Transport ◽  
Theoretical Evidence ◽  
Predicted Values

Existing experimental and theoretical evidence suggests that precapillary diffusion of O2 and CO2 occurs between arterioles and tissue under normal physiologic conditions. However, limited information is available on arteriolar gas transport during anemia. With use of a mathematical model of an arteriolar network in brain tissue, anemic hematocrits of 35, 25, and 15% were modeled to determine the effect of anemia on the exchange, the change in the equilibrium tissue O2 and CO2 tensions, and the increase in blood flow needed to restore tissue oxygenation. We found that the blood Po2 exiting the network fell from 66 mm Hg normally to 48 mm Hg during the severest anemia. Concurrently, the equilibrium tissue O2 tensions dropped from 44 to 23 mm Hg. For CO2 the exit blood Pco2 was 58 mm Hg for a 15% hematocrit, an increase of 4 mm Hg from the normal value, and equilibrium tissue Pco2 increased from 56 to 61 mm Hg. Blood flow increases from normal values necessary to offset the effects of the decreased O2 delivery to the tissue were 26, 86, and 222%, respectively, for hematocrits of 35, 25, and 15%. We compared our model results with recent experimental studies that have suggested that the amount of O2 diffusion is much higher than predicted values. We found that these experimental O2 gradients are three to four times larger than theoretical.

scholarly journals Biophotonics for Biofuel Upgradation

2017 ◽  
Vol 25 (4) ◽  
pp. 262-266
Author(s):  
Gopinath Rana ◽  
Tanusri Mandal
Keyword(s):  
Carbon Dioxide ◽  
Flame Temperature ◽  
Experimental Studies ◽  
16S Rrna Gene Sequencing ◽  
Illumina Miseq ◽  
Rrna Gene ◽  
Fuel Gas ◽  
Photo Bioreactor ◽  
Rrna Gene Sequencing ◽  
Downstream Analysis

AbstractExperimental studies have been made to find out Cyanobacterias’ biophotonical response in gaseous-fuelation and carbon dioxide fixation during photo-anaerobic digestion. A new horizontal type photo-bioreactor has been designed by using environment hazard plastic bottles and it works ideally for anoxygenic cyanobacterial growth. Through ‘V3-metagenomics’ of 16S rRNA gene sequencing by paired-end Illumina MiSeq and downstream analysis by QIIME program, we have identified anaerobic cyanobacteria, represent the orders YS2 and Streptophyta. OTUs have been identified by aligning against Greengenes and Silva databases, separately. The flame temperature of the fuel gas is 860°C and the percent-content of carbon dioxide (CO2) is 17.6%.

scholarly journals Predictors of drug prescription in nursing home residents: results from the INCUR study

2021 ◽  
Author(s):  
Laura Calcaterra ◽  
Marco Proietti ◽  
Edoardo Saporiti ◽  
Vanessa Nunziata ◽  
Yves Rolland ◽  
...  
Keyword(s):  
Nursing Home ◽  
Older Persons ◽  
Drug Prescription ◽  
Frailty Index ◽  
Nursing Home Residents ◽  
Public Health Issue ◽  
Linear Regression Models ◽  
The Mean ◽  
Independent Association ◽  
Post Hoc

AbstractPolypharmacy represents a major clinical and public health issue in older persons. We aimed to measure the prevalence of polypharmacy, and the main predictors of drug prescription in nursing home residents. Post hoc analyses of the “Incidence of pNeumonia and related ConseqUences in nursing home Residents” (INCUR) study were conducted. Polypharmacy was defined as the prescription of 5 or more drugs. A frailty index (FI) was computed according to the model proposed by Rockwood and Mitnitski using 36 health deficits, including diseases, signs, symptoms, and disabilities. Linear regression models were performed to identify the main predictors of the number of prescribed drugs. The INCUR study enrolled 800 patients (mean [SD] age 86.2 [4.1] years, 74.1% women). The mean number of medications prescribed at the baseline was 8.5 (SD 4.1). Prevalence of polypharmacy was found 86.4%. The mean FI was 0.38 (SD 0.10). A fully adjusted linear multivariate regression model found an inverse and independent association between age and number of prescribed drugs (beta − 0.07, 95% CI − 0.13, − 0.02; p = 0.005). Conversely, the FI was independently and positively associated with the number of medications (beta 4.73, 95% CI 1.17, 8.29; p = 0.009). The prevalence of polypharmacy is high among older persons living in nursing home. Age and FI are significantly associated with the number of drugs. The number of prescribed drugs tends to decrease with age, whereas a direct association with frailty is reported.

scholarly journals nà-Cleft (non-)exhaustivity: Variability in Akan

2021 ◽  
Author(s):  
Joseph P. De Veaugh-Geiss
Keyword(s):  
Information Retrieval ◽  
Experimental Studies ◽  
Definite Descriptions ◽  
Exploratory Analysis ◽  
Response Patterns ◽  
Unified Approach ◽  
Pragmatic Analysis ◽  
Incremental Information ◽  
Post Hoc

This paper presents two experimental studies on the exhaustive inference associated with focus-background nà-clefts in Akan (among others, Boadi 1974; Duah 2015; Grubic, Renans & Duah 2019; Titov 2019), with a direct comparison to two recent experiments on German es-clefts employing an identical design (De Veaugh-Geiss et al. 2018). Despite the unforeseen response patterns in Akan in the incremental information-retrieval paradigm used, a post-hoc exploratory analysis reveals striking parallels between the two languages. The results are compatible with a unified approach both (i) cross-linguistically between Akan and German; and (ii) cross-sententially between nà-clefts (α nà P, ’It is α who did P’) and definite pseudoclefts, i.e., definite descriptions with identity statements (Nipa no a P ne α , ’The person who did P is α ’) (Boadi 1974; Ofori 2011). Participant variability in (non-)exhaustive interpretations is accounted for with a discourse-pragmatic analysis of cleft exhaustivity (Pollard & Yasavul 2016; De Veaugh-Geiss et al. 2018; Destruel & De Veaugh-Geiss 2018).

scholarly journals Venous Admixture Effect during One-lung Anaesthesia

1972 ◽  
Vol 1 (1) ◽  
pp. 45-53 ◽  
Author(s):  
T. A. Torda ◽  
H. D. O'Brien ◽  
C. McCulloch ◽  
K. Tsui
Keyword(s):  
Carbon Dioxide ◽  
Cardiac Output ◽  
Oxygen Saturation ◽  
Oxygen Content ◽  
Carbon Dioxide Tension ◽  
Venous Admixture ◽  
Content Difference ◽  
Venous Oxygen Content ◽  
The Mean

The venous admixture was measured before, during, and after deflation of one lung during anaesthesia for thoracotomy in 10 subjects ventilated with 50% oxygen. The mean oxygen saturation fell from 99% before deflation of the lung to 89% after 30 minutes’ atelectasis. The pH and carbon dioxide tension did not change significantly. The shunt was 38% of cardiac output five minutes after and 41% 30 minutes after deflation. The reciprocal of the arterial venous oxygen content difference correlated positively with the shunt, suggesting that increased venous admixture is accompanied by increased cardiac output.

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