Carbon Dioxide Output Research Articles

Ferrocene addition for suppression of hydrogen sulfide formation during thermal recovery of oil sand bitumen

The occurrence of H2S during thermal recovery production becomes one of the biggest challenges. While various industrial processes can remove H2S at the surface, to prevent the formation of H2S in reservoir is much less successful. Ferrocene was chosen as the likely target reagent after a review of iron compound volatility and environmental considerations. To evaluate this, closed system gold tube pyrolysis experiments were conducted on an Athabasca oil sand at 350–650 °C to examine gas compositions with and without ferrocene addition. Slightly higher hydrocarbon gas yields have been observed from samples with ferrocene addition likely caused by ferrocene decomposition. Yields of carbon dioxide (CO2) are higher in plain oil sand samples before 550 °C but the trend was reversed afterwards with more CO2 being generated from ferrocene addition ones. H2S yields in samples without ferrocene increase from background value at 350 °C to the highest amount at 450 °C then disappear above 625 °C. Thermal decomposition of organosulfur compounds is supposed to be the main route for the occurrence of H2S in the sulfur-rich bitumen pyrolysis. Ferrocene is proved to be powerful H2S removal reagent as no H2S can be detected from ferrocene addition samples. The reactions of ferrocene with H2S may form iron sulfides, cyclopentadiene and hydrogen. Complete, rapid, and predictable reactions and inert reaction products make ferrocene as an ideal in situ H2S scavenger, while the potential for the deposition of metal sulfides may reduce the permeability. Ferrocene is widely available for industry, however, the unit cost has not been assessed in this study.

Improved In Situ Burn Efficiencies: An Overview of New Techniques and Technologies Resulting in Cleaner Burns

ABSTRACT Number: 1141152 In situ burning is an efficient response method that quickly removes large quantities of oil from the marine environment eliminating the need for collection, storage, and transport. The combustion of hydrocarbons mainly yields carbon dioxide and water; however, it also creates large plumes of black carbon soot and residues of incompletely burned oils. Three research projects focusing on improving burn efficiencies show promise to make an already efficient response method even more efficient. Specifically, a technology to increase heat transfer back into the crude oil result in more complete combustion greatly reducing carbon soot is nearing completion and will soon be ready for transfer to industry for commercialization. A study reconfiguring existing booming techniques allows more oxygen into the fire resulting in decreased soot production and cleaner burns. Finally, a fundamental study into the phenomena of fire whirls demonstrates a dramatic increase in volumes of oil burned while greatly reducing emissions. Emissions and efficiencies of the studies are compared with standard pool fires.

Sodium silicate/waterborne epoxy resin hybrid-modified Chinese fir wood

The use of fast-growing wood can reduce the environmental impact of the wood industry, but the low strength and flammability of these woods prevent their widespread application. Chinese fir not only has the general defect of fast-growing wood, but also has weak permeability due to aspirated pits. To improve its performance, environment-friendly modifier sodium silicate (SS) and WEP (waterborne epoxide resin) as the dipping solution, microwave pretreatment and multi-step emptying-pressure (MSEP) impregnation method were employed to prepare hybrid-modified wood. Microwave pretreatment was found to destroy pit membranes of Chinese fir and increase permeability. WEP addition reduced the wood’s -OH content and promoted formation of more Si–O–Si structures, while also forming a fusiform hybrid structure with SS through Si–O–C bonds. The mechanical properties and water resistance of SS/WEPW (hybrid-modified wood) were higher than those modified by SS alone. The bending strength, elastic modulus, compressive strength, and transverse, tangential, and radial hardness of SS/WEPW5% (5% WEP) reached 97.20, 8504.87, 57.73, 5113.50, 2536.37, and 2192.35 MPa, respectively. The water resistance performance was also significantly improved. Compared with SSW, the 7-day weight leaching ratio (WLR) and water absorption rate (WAR) were reduced by 49.26 and 11.09, respectively, and the 14-day anti-shrink efficiency (ASE) of SS/WEPW5% can reach 86.87%. Furthermore, the flame retardant and smoke suppression performances of hybrid-modified wood were also improved, with the heat release rate (HRR), smoke produce rate (SPR), mean carbon monoxide yield (mean COY), and mean carbon dioxide yield (mean CO2Y) of SS/WEPW5% significantly lower and the peak of CO and CO2 release almost 1/10th that of unmodified wood. SS/WEP hybrid-modified wood was improved in terms of mechanical properties, water resistance performance, and flame retardancy, which laid the foundation of its use as a high-performance wooden material.

Heart rate recovery is useful for evaluating the recovery of exercise tolerance in patients with heart failure and atrial fibrillation

This study aimed to examine the factors that contribute to improvement of exercise tolerance in patients with heart failure (HF) and atrial fibrillation (AF) following cardiac rehabilitation. Our hypothesis is that parasympathetic values are important for recovering exercise tolerance in those patients. We included 84 consecutive patients with HF and AF (mean age: 69 ± 15 years, 80% men). All of the patients underwent a cardiopulmonary exercise test and had pre and post 5 month cardiac rehabilitation assessed. After 155 ± 11 days and 44 ± 8 sessions, 73 patients (86%) showed an increase in peak oxygen uptake (VO2) and VO2 at the anaerobic threshold. In univariate linear regression analysis, the % change in heart rate recovery, plasma B-type natriuretic peptide levels, resting heart rate, and the minute ventilation /carbon dioxide output slope were significantly related to that of peak VO2 (p < 0.01, p = 0.03, p = 0.02, p < 0.01, respectively). Stepwise multivariate linear regression analysis showed that the % change in heart rate recovery was independently related to that of peak VO2 (p < 0.05). Our results suggest that heart rate recovery is closely associated with recovery of exercise tolerance in patients with HF and AF after CR.

Respiratory Muscle Strength as an Indicator of the Severity of the Apnea-Hypopnea Index: Stepping Towards the Distinction Between Sleep Apnea and Breath Holding.

Background and objectiveThe aim of this study was to investigate whether the maximum inspiratory and expiratory pressure are correlated with the apnea-hypopnea index (AHI) in patients with obstructive sleep apnea syndrome (OSAS).MethodsFifty-two patients with OSAS were divided into two groups (AHI, events/hours: <30, n=28, versus ≥30, n=24). For each patient, anthropometric characteristics, spirometry parameters, maximum inspiratory (MIP) and expiratory pressure (MEP), and cardiopulmonary function (CPF) parameters (oxygen uptake at rest (VO2), carbon dioxide output (VCO2), heart rate (HR), minute ventilation (VE), tidal volume at inspiratory (TVin) and expiratory (TVex), breath frequency (fβ), end-tidal carbon dioxide pressure (PETCO2), end-tidal oxygen pressure (PETO2), and mean arterial pressure (MAP)) in sitting position for three minutes were recorded. The independent t-test was used to measure the differences between groups (events/hours <30 versus ≥30) and Pearson correlation analysis was used for statistical comparison between parameters.ResultsResults showed differences between groups (AHI, events/h ≥30 versus <30) in MIP (102.0±18.3 versus 91.1±12.1 % of predicted, p=0.013) and CPF parameters TVin (0.8±0.2 versus 0.7±0.1, L, p=0.047), PETCO2 (34.6±4.2 versus 31.4±3.7, mmHg, p=0.007), and MAP (88.4±6.5 versus 82.9±6.2, mmHg, p=0.003). Pearson correlation analysis between respiratory muscle strength (MIP and MEP) and polysomnography (PSG) parameters, MIP is related to AHI (r=.332, p=0.016) and desaturation index (r=.439, p=0.001), as well as MEP to percent of REM sleep stage (r=-.564, p<0.001).ConclusionThe data from the present study support that maximal inspiratory pressure relates to the severity of AHI and intermittent breath-holding during sleep increases the inspiratory muscle strength.

Red seaweed (Asparagopsis taxiformis) supplementation reduces enteric methane by over 80 percent in beef steers.

The red macroalgae (seaweed) Asparagopsis spp. has shown to reduce ruminant enteric methane (CH4) production up to 99% in vitro. The objective of this study was to determine the effect of Asparagopsis taxiformis on CH4 production (g/day per animal), yield (g CH4/kg dry matter intake (DMI)), and intensity (g CH4/kg ADG); average daily gain (ADG; kg gain/day), feed conversion efficiency (FCE; kg ADG/kg DMI), and carcass and meat quality in growing beef steers. Twenty-one Angus-Hereford beef steers were randomly allocated to one of three treatment groups: 0% (Control), 0.25% (Low), and 0.5% (High) A. taxiformis inclusion based on organic matter intake. Steers were fed 3 diets: high, medium, and low forage total mixed ration (TMR) representing life-stage diets of growing beef steers. The Low and High treatments over 147 days reduced enteric CH4 yield 45 and 68%, respectively. However, there was an interaction between TMR type and the magnitude of CH4 yield reduction. Supplementing low forage TMR reduced CH4 yield 69.8% (P <0.01) for Low and 80% (P <0.01) for High treatments. Hydrogen (H2) yield (g H2/DMI) increased (P <0.01) 336 and 590% compared to Control for the Low and High treatments, respectively. Carbon dioxide (CO2) yield (g CO2/DMI) increased 13.7% between Control and High treatments (P = 0.03). No differences were found in ADG, carcass quality, strip loin proximate analysis and shear force, or consumer taste preferences. DMI tended to decrease 8% (P = 0.08) in the Low treatment and DMI decreased 14% (P <0.01) in the High treatment. Conversely, FCE tended to increase 7% in Low (P = 0.06) and increased 14% in High (P <0.01) treatment compared to Control. The persistent reduction of CH4 by A. taxiformis supplementation suggests that this is a viable feed additive to significantly decrease the carbon footprint of ruminant livestock and potentially increase production efficiency.

Production of light hydrocarbons from organosolv lignin through catalytic hydrogenation and subsequent fast pyrolysis

Valorization and utilization of lignin have been drawing increasing attention recently. Hydroprocess is one of the main technologies, which can reduce organic compounds and partially depolymerize the macromolecular structure of lignin. The mechanism of lignin hydroprocess has been extensively discussed focusing on hydrogenolysis. In contrast, the solid residue regarded as unreacted or depolymerized lignin has drawn less attention so far. This study proposes an integrated process that consists of catalytic hydrogenation and subsequent fast pyrolysis for valorizing lignin. The results showed that 48−87 wt.% of solid product could be recovered as hydrogenated lignin (H-EOL) after hydrogenation at 200–250 ℃ for 1−7 h. Chemical structure of H-EOL was comprehensively investigated by means of elemental analysis, FTIR, 13C &1H NMR, and TGA. Furthermore, behavior of fast pyrolysis of H-EOL was detected here for the first time. H-EOL has higher hydrogen to carbon atomic effective ratio(H/Ceff ratio) and achieves the increasing reactivity of thermal decomposition. H-EOL yields light olefins double as much as raw ethanol organosolv lignin (EOL). And the formation of alkanes (C1-C4), benzene, and toluene was promoted to various degrees, while the yield of carbon monoxide, carbon dioxide, and vapor decreased. A novel and efficient pretreatment method has been provided to valorize lignin, which is instructive for subsequent research.

Importance of Cardiopulmonary Exercise Testing amongst Subjects Recovering from COVID-19.

The cardiopulmonary exercise test (CPET) provides an objective assessment of ventilatory limitation, related to the exercise minute ventilation (VE) coupled to carbon dioxide output (VCO2) (VE/VCO2); high values of VE/VCO2 slope define an exercise ventilatory inefficiency (EVin). In subjects recovered from hospitalised COVID-19, we explored the methodology of CPET in order to evaluate the presence of cardiopulmonary alterations. Our prospective study (RESPICOVID) has been proposed to evaluate pulmonary damage’s clinical impact in post-COVID subjects. In a subgroup of subjects (RESPICOVID2) without baseline confounders, we performed the CPET. According to the VE/VCO2 slope, subjects were divided into having EVin and exercise ventilatory efficiency (EVef). Data concerning general variables, hospitalisation, lung function, and gas-analysis were also collected. The RESPICOVID2 enrolled 28 subjects, of whom 8 (29%) had EVin. As compared to subjects with EVef, subjects with EVin showed a reduction in heart rate (HR) recovery. VE/VCO2 slope was inversely correlated with HR recovery; this correlation was confirmed in a subgroup of older, non-smoking male subjects, regardless of the presence of arterial hypertension. More than one-fourth of subjects recovered from hospitalised COVID-19 have EVin. The relationship between EVin and HR recovery may represent a novel hallmark of post-COVID cardiopulmonary alterations.

On the initiation of blow-out from cooktop burner jets: A simplified energy-based description for the onset of laminar flame extinction in premixed hydrogen-enriched natural gas (HENG) systems

Due to the prohibitive financial expense and logistical difficulties of a wholesale changeover from natural gas to hydrogen, hydrogen-enriched natural gas (HENG) offers a more viable intermediate solution for offsetting the carbon dioxide output of domestic gas usage and reducing the blow-out susceptibility of natural gas flames. In order to formulate a practically useful description of the blow-out threshold, the present work addresses the minimum energy per unit volume of premixed gas required for the sustained combustion of HENG fuels with molar hydrogen concentrations between zero and 50 mol%. By considering a ring burner comprising circular burner jet apertures with diameters in the range 1.0–2.4 mm, this critical energy density was demonstrated to increase linearly with the mean velocity of the admitted gas premixture, approaching a value that was common to all of the investigated HENG compositions in the limit of zero flow. Furthermore, despite flame morphology varying substantially as a function of flow conditions, the visible surface area of critically stable flames consistently exhibited an empirical squared dependence on the power generated by combusting fuel. By combining these correlations, the onset of blow-out was shown to be well-approximated by a formula that relates the critical surface-averaged laminar burning velocity to the mean velocity of gas molecules at the burner jet. This model provides a simplified means of predicting blow-out conditions from measurable input parameters and could serve as an invaluable asset for the design of new HENG burner systems or the retrofitting of existing natural gas appliances.

Intercept of minute ventilation versus carbon dioxide output relationship as an index of ventilatory inefficiency in chronic obstructive pulmonary disease.

BackgroundVentilatory inefficiency contributes to exercise intolerance in chronic obstructive pulmonary disease (COPD). The intercept of the minute ventilation (V˙ E) vs. carbon dioxide output (V˙ CO2) plot is a key ventilatory inefficiency parameter. However, its relationships with lung hyperinflation (LH) and airflow limitation are not known. This study aimed to evaluate correlations between the V˙ E/V˙ CO2 intercept and LH and airflow limitation to determine its physiological interpretation as an index of functional impairment in COPD.MethodsWe conducted a retrospective analysis of data from 53 COPD patients and 14 healthy controls who performed incremental cardiopulmonary exercise tests (CPETs) and resting pulmonary function assessment. Ventilatory inefficiency was represented by parameters reflecting the V˙ E/V˙ CO2 nadir and slope (linear region) and the intercept of V˙ E/V˙ CO2 plot. Their correlations with measures of LH and airflow limitation were evaluated.ResultsCompared to control, the slope (30.58±3.62, P<0.001) and intercept (4.85±1.11 L/min, P<0.05) were higher in COPDstages1-2, leading to a higher nadir (31.47±4.47, P<0.01). Despite an even higher intercept in COPDstages3-4 (7.16±1.41, P<0.001), the slope diminished with disease progression (from 30.58±3.62 in COPDstages1-2 to 26.84±4.96 in COPDstages3-4, P<0.01). There was no difference in nadir among COPD groups and higher intercepts across all stages. The intercept was correlated with peak V˙ E/maximal voluntary ventilation (MVV) (r=0.489, P<0.001) and peak V˙ O2/Watt (r=0.354, P=0.003). The intercept was positively correlated with residual volume (RV) % predicted (r=0.571, P<0.001), RV/total lung capacity (TLC) (r=0.588, P<0.001), peak tidal volume (VT)/FEV1 (r=0.482, P<0.001) and negatively correlated with rest inspiratory capacity (IC)/TLC (r=−0.574, P<0.001), peak VT/TLC (r=−0.585, P<0.001), airflow limitation forced expiratory volume in 1 s (FEV1) % predicted (r=−0.606, P<0.001), and FEV1/forced vital capacity (FVC) (r=−0.629, P<0.001).ConclusionsV˙ E/V˙ CO2 intercept was consistently correlated with worsening static and dynamic LH, pulmonary gas exchange, and airflow limitation in COPD. The V˙ E/V˙ CO2 intercept emerged as a useful index of ventilatory inefficiency in COPD patients.

Clinical study on the characteristics of exercise pathophysiological in patients with severe heart failure

Objective: The cardiopulmonary function of patients with chronic heart failure (CHF) was severely limited, but the holistic integrative exercise pathophysiology is still unclear. Methods: After signed the consent form, Eighty three patients with severe CHF from October 2016 to October 2017 in Fuwai Hospital were performed Ramp incremental loading program CardioPulmonary Exercise Testing (CPET), and 12 normal subjects served as control. CPET were performed according to standard of Harbor-UCLA MC and the circulatory, respiratory and metabolic parameters during CPET were measured and analyzed. Results: Peak oxygen uptake (Peak VO2) in CHF (14.33±2.69) ml/(min·kg), (44.25±14.74)%pred was significantly lower than control ((29.42±5.46) ml/(min·kg), (83.88±6.28)%pred). Other core parameters of CPET such as anaerobic threshold (AT), peak oxygen pulse, oxygen uptake efficiency platform (OUEP), the lowest of carbon dioxide output ventilation ratio (Lowest VE/VCO2), and carbon dioxide output ventilation slope (VE/VCO2 Slope) in CHF were significantly different with the control group(P<0.01). The core parameters of lung function, such as forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC, and carbon monoxide diffusion (DLCO) were significantly decreased (P<0.01). Systolic blood pressure during all stages of CPET in CHF was significantly lower than control group (P<0.05); Heart rate at AT, peak and recovery stages were significantly lower than control (P<0.01). Minute ventilation, tidal volume and respiratory frequency at rest, warm-up were significantly higher than control (P<0.05). Tidal volume at recovery was significantly higher than control (P<0.05). VO2 at AT, peak and recovery stages in CHF were significantly higher than control (P<0.01). Oxygen pulse at AT and peak were significantly higher than control (P<0.01). Pulse oxygen saturation during all stages of CPET in CHF were significantly lower than control (P<0.01). Conclusion: The decreased holistic functional capacity of cardiogenic CHF dominantly due to circulatory limitation, and secondly due to respiratory and metabolic limitation.

Novel castor-oil-based flame-retardant and flexible epoxy resins: synthesis and properties

A novel castor-oil-based and phosphorus-containing epoxy resin (flame-retardant epoxy resin (FREP)) and a curing agent – castor oil polybasic acid (AACO) – with high flame retardancy and flexibility were successfully synthesized. The chemical structures of FREP and AACO were characterized by Fourier transform infrared spectrometry (FTIR) and hydrogen-1 (1H) nuclear magnetic resonance spectroscopy. The epoxy resin components were prepared by using bisphenol A epoxy resin (diglycidyl ether of bisphenol A (DGEBA)) with different mass contents of FREP and AACO. DGEBA with 40 wt% FREP (FREP40) possessed a large limiting oxygen index of 29.3%. Cone calorimetry showed that the heat release and smoke production were reduced for both DGEBA with 20 wt% FREP (FREP20) and FREP40 in comparison with those of pure resin (FREP0), indicating that the smoke release and fire hazard of epoxy resin composites with FREP were reduced. Thermogravimetry–infrared spectroscopy suggested that the yields of toxic carbon monoxide (CO), carbon dioxide (CO2) and other pyrolysis products were significantly reduced. FTIR and X-ray photoelectron spectroscopy showed that FREP40 outperformed FREP0 in carbon-forming capacity. The introduction of FREP and AACO effectively increased the elongation at break of pure epoxy resins. FREP and AACO provide a promising strategy for synthesis of epoxy resins with excellent flame retardancy, smoke suppression and flexible performance.

BIOMETHANE POTENTIAL OF INVASIVE AQUATIC WEED WATER PRIMROSE

This study aims to examine the perspective of feedstock for producing biomethane from invasive aquatic weed water primroses (Ludwigia Hyssopifolia). The methane yield and methane content of biogas were analyzed and studied. The calculating methods of theoretical methane yield based on the elemental application or the theoretical chemical oxygen demand (COD) number were showed. The percentage of element chemicals, carbon (C), hydrogen (H), oxygen (O), nitrogen (N), and sulfur (S) of raw materials were analyzed, and results were 40.2%, 5.03%, 22.13%, 1.8% and 0.24%, respectively. The plant biomass was contained moisture content, volatile carbon, fixed carbon and ash were 7.28%, 63.07%, 1.28% and 28.37%, respectively. From the water primroses calculated yield of methane (CH4), carbon dioxide (CO2) and ammonia (NH3) results were 54.90%, 41.40% and 3.70%, respectively. Therefore, the aquatic weed water primroses biomass are suitable feedstock for biogas production as well as future scale-up studies.

Вплив різних доз біопрепарату Меганіт Нірбатор на емісію парникових газів з курячого посліду

Goal. To determine the effectiveness of different doses of the biological preparation Meganit Nirbator on the emission of greenhouse gases (CH4, CO2) from chicken manure under the mesophilic regime of anaerobic fermentation (in vitro). Methods. The study was conducted using laboratory, analytical and mathematical methods. Laboratory methods — to establish the level of greenhouse gas emissions from chicken manure when using different doses of the biological preparation Meganit Nirbator; analytical — to analyze and justify the results; mathematical and statistical — to assess the reliability of research results. Results. Based on the results obtained during the study, it was found that the use of the biological product Meganit Nirbator in chicken manure, regardless of the dose activated the process of methanogenesis during the study period, which was confirmed by increasing pH to 9.2 units. Simultaneously with the higher pH value in the studied substrate, the introduction of the biological product Meganit Nirbator into chicken manure during anaerobic fermentation (in vitro) under the mesophilic regime caused a higher yield of methane and carbon dioxide: in the variant I — by 11.8%, in the variant II — by 22.9%, in the variant III — by 27.9%, compared with the control. Conclusions. The effective influence of the biological preparation Meganit Nirbator on the emission of greenhouse gases — methane and carbon dioxide from chicken manure under the mesophilic regime of anaerobic fermentation (in vitro) has been experimentally proved and scientifically substantiated. According to the results of research, the most effective influence on the emission of CH4 and CO2 has a biological product Meganit Nirbator in a dose of 50 ml (16.7%), which increases their quantitative indicators by 22.9%, while increasing the dose of this drug does not significantly affect the yield of the tested gases. Therefore, the biological product Meganit Nirbator can be used as a stimulant to intensify the yield of biogas from chicken manure during processing in biogas plants, thereby minimizing the negative impact of agriculture, in particular poultry, on the environment.

Factors related to the discontinuation and mortality rates of a cardiac rehabilitation programme in patients with Chagas disease: a 6-year experience in a Brazilian tertiary centre.

To describe the clinical and sociodemographic characteristics of participants as well as discontinuation and mortality rates in a cardiac rehabilitation programme (CRP) tailored to Chagas disease (CD). Participants underwent functional capacity, anthropometry and cardiac function evaluations before beginning a CRP. Univariate and multivariate Cox proportional hazards models were performed to investigate the associations between clinical and sociodemographic characteristics at baseline with discontinuation rates and deaths. Forty-two patients were enrolled in the CRP (61.9% men, mean age of 58.1±11.8years). During a median follow-up period of 10.8months, 74% discontinued and 14% died while enrolled in CRP. 34% of the patients who discontinued CRP died during follow-up. White race (HR=0.09; 95% CI 0.01-1.00), right ventricular systolic dysfunction (HR=10.54; 95% CI 1.24-89.50) and oxygen pulse (HR=0.69; 95% CI 0.48-0.99) were independently associated with death while enrolled in CRP. Married status (HR=0.44; 95% CI 0.21-0.95) was independently associated with discontinuation rates from CRP. VO2 peak (HR=0.85; 95% CI 0.74-0.98) and CRP discontinuation due to CD-related reasons (HR=8.33; 95% CI 1.91-36.27) were the variables independently associated with death after discontinuation of CRP. In this population, sociodemographic aspects and severity of CD were important determinants of CRP discontinuation and mortality.

Effect of temperature on the production of a recombinant antivenom in fed-batch mode.

In the pharmaceutical industry, nanobodies show promising properties for its application in serotherapy targeting the highly diffusible scorpion toxins. The production of recombinant nanobodies in Escherichia coli has been widely studied in shake flask cultures in rich medium. However, there are no upstream bioprocess studies of nanobody production in defined minimal medium and the effect of the induction temperature on the production kinetics. In this work, the effect of the temperature during the expression of the chimeric bispecific nanobody CH10-12 form, showing high scorpion antivenom potential, was studied in bioreactor cultures of E. coli. High biomass concentrations (25 g cdw/L) were achieved in fed-batch mode, and the expression of the CH10-12 nanobody was induced at temperatures 28, 29, 30, 33, and 37°C with a constant glucose feed. For the bispecific form NbF12-10, the induction was performed at 29°C. Biomass and carbon dioxide yields were reported for each culture phase, and the maintenance coefficient was obtained for each strain. Nanobody production in the CH10-12 strain was higher at low temperatures (lower than 30°C) and declined with the increase of the temperature. At 29°C, the CH10-12, NbF12-10, and WK6 strains were compared. Strains CH10-12 and NbF12-10 had a productivity of 0.052 and 0.021 mg/L/h of nanobody, respectively, after 13 h of induction. The specific productivity of the nanobodies was modeled as a function of the induction temperature and the specific growth rates. Experimental results confirm that low temperatures increase the productivity of the nanobody.Key points• Nanobodies with scorpion antivenom activity produced using two recombinant strains.• Nanobodies production was achieved in fed-batch cultures at different induction temperatures.• Low induction temperatures result in high volumetric productivities of the nanobody CH10-12.

Philippine Normal Reference Values for Cardiopulmonary Exercise Testing

Performance on cardiopulmonary exercise test (CPET) is influenced by genetic, racial and environmental factors. This study aimed to establish the Maximum Working Capacity, Peak oxygen uptake (VO₂), Peak carbon dioxide output (VCO₂), Tidal Volume (TV) for normal Filipinos during exercise and derive prediction equation models for Maximum Working Capacity, Peak VO₂, Peak VCO₂ and maximum attained TV. The maximal cardiopulmonary responses were analyzed for one hundred eighteen healthy sedentary adult Filipino subjects who underwent CPET using a symptom limited incremental progressive cycle ergometer driven protocol. A Vista Mini-CPX Model 17670 was used. Models for predicting VO₂ max, VCO₂ peak, TV peak, and Work Max were derived with height, weight, age and sex being screened for significance as predictors. Linear and non-linear regression analyses were done. The maximum working capacity for males was 154.21±26.6 watts and 93.02±15.57 watts for females while the peak VO₂ for males was 4.90±3.11 and 4.56±2.41 liters/minute for females. The predictive formulae derived from this study for maximum work capacity, peak VO₂, VCO₂ and tidal volume had acceptable correlation coefficients and performed as well as other published predictive equations based on Caucasian and Asian populations. Differences between races as to performance in exercise testing was confirmed in this study.

Literature review on the usage of six sigma techniques for improvement of quality in soft drink beverage and bottling industries

The main goals of a manufacturing plant is to improve quality, throughput and increase productivity by reducing ineffective time. In order to do so various areas needs to be looked at and one such focus is on quality improvement, quality has various dimension’s and meeting all these dimension require a sound approach like Six Sigma. The soft drink beverage industry has a complex manufacturing process and there are strict quality measures due to the direct relation which it has with its consumers. In order to accomplish such a need six sigma approach is essential. In regard to the beverage industry quality issues starts of from carbon dioxide yield to bottle filling issues. This study focusses on bringing in different literature which have used six sigma tools and techniques in the bottle and beverage industry. Based on the study it was found techniques such as pareto analysis, fish bone diagram, design of experiment, analysis of variance (ANOVA), control charts are widely used. This is done in order to provide a sound framework on what techniques can be applied when an issue on quality arises.

Non-conventional CO2 sequestration via Vitamin C promoted green reaction: Yield evaluation

Carbon dioxide increase in the atmosphere is a relentless rise process. Many mitigation measures aimed at the reduction of carbon dioxide emissions coupled with capture in variously stable sequestration systems have been proposed over time.In a previous paper (Pastero, 2019), we proposed a new and green method to capture carbon dioxide avoiding the usage of hazardous reagents and the production of harmful compounds. The method involves the application of an aqueous solution of calcium ascorbate (vitamin C) as the only reagent and the precipitation of calcium oxalate as the main reaction product.The role of the chemical and physical process variables controlling the reaction has been investigated in order to increase significantly and stabilize the reaction yield in terms of CO2-sequestration capacity. In the present paper, we evaluated the performance of our method quantitatively, referring to two simple experimental setups: the maximum carbon dioxide yield exceeded 60 %, meaning that every 100 mol of carbon dioxide fed to the capturing system, 60 mol are removed and stored into a stable solid phase. This boost in the method’s performance was obtained optimizing the key-parameters of the reaction and increasing the exchange surface.

Physiological Changes Differ between Responders and Nonresponders to Pulmonary Rehabilitation in COPD.

Not all patients with chronic obstructive pulmonary disease (COPD) experience similar benefits after pulmonary rehabilitation (PR). This pre-post PR study used a large sample of patients with COPD to determine whether PR-induced changes of oxygen uptake (V˙O2) kinetics and exercise responses of V˙O2, carbon dioxide output (V˙CO2), minute ventilation (V˙E), V˙E/V˙CO2, breathing frequency, and tidal volume differed between responders and nonresponders to PR. Responders to PR were defined as patients with a minimal clinically important increase in endurance time of 105 s. Isotime (=180 s) values of V˙O2, V˙CO2, V˙E, V˙E/V˙CO2, breathing frequency, and tidal volume; gains of V˙O2, V˙CO2, and V˙E; and V˙O2 mean response time of 183 patients with COPD (forced expiratory volume in 1 s: 56% ± 19% predicted) were compared between pre- and post-PR constant work rate tests. After PR, only the group of responders significantly decreased V˙O2 mean response time (P < 0.05), V˙CO2 gain, V˙E gain, and isotime values of V˙CO2, V˙E, and V˙E/V˙CO2 (all, P < 0.001), while also improving their breathing pattern (e.g., decreased breathing frequency isotime value; P < 0.0001). These changes were not observed in the group of nonresponders. Changes in physiological exercise responses were correlated with changes in physical performance (e.g., correlation between changes in V˙O2 mean response time and endurance time: P = 0.0002, r = -0.32). PR-induced changes in physiological exercise responses differed between responders and nonresponders. Physiological changes are relevant to explain the variable improvements of physical performance after PR in patients with COPD.