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PubMed2002

Plasma, milk and faecal progesterone concentrations during the oestrous cycle of lactating dairy cows with different milk yields.

The hypotheses tested in this study were that neither average progesterone (P4) concentrations in plasma and milk nor average progesterone metabolites concentrations in faeces would differ during an oestrous cycle in two groups of cows with differing daily milk yields. High producing (HP = 8) and low producing (LP = 8) dairy cows were selected randomly for the study. Their oestrous cycles were initially synchronised using P4 and prostaglandin F2alpha. Chromic oxide capsules were administered twice daily to measure total faecal output. Samples of blood, faeces and milk were taken daily throughout one oestrous cycle, plasma and milk P4, and faecal progesterone metabolites (FP4M) assayed. The average daily milk yields in the two groups were 30.8 and 21.9l per day, respectively (P < 0.0001), although daily faecal output was similar in both the groups (HP, 7.7 versus LP, 6.9 kg DM; P = 0.24). Mean plasma and milk P4 concentrations were similar in both the groups (plasma P4, 4.12 versus 4.05 ng/ml; P = 0.3; milk P4, 8.2 versus 8.3; P = 0.9) during dioestrus. Average daily excretion of P4 to the milk was greater in HP than LP cows (252 versus 185 microg, P = 0.04). Neither concentration nor the daily yield of FP4Ms was affected by level of milk yield (concentration: 12.2 versus 11.5 microg/g; daily yield: 89.1 versus 82.9 mg per day; P > 0.05). These data showed that the concentrations of P4 in plasma and milk, and the concentrations and daily yields of FP4M were not affected by the level of daily milk yields which differed by about 41% of the LP average of 21.9l.

Animals↗
PubMed2003

Effects of fly ash and Helminthosporium oryzae on growth and yield of three cultivars of rice.

A 120-day greenhouse experiment was conducted to study the effects of various fly ash concentrations (0%, 20%, 40%, 60%, 80% and 100% vol/vol) with normal field soil and Helminthosporium oryzae on the growth and yield of three cultivars (Pusa Basmati, Pant-4 and Pant-10) of rice, Oryza sativa L. Application of 20% and 40% fly ash with soil caused a significant increase in plant growth and yield of all the three cultivars. Forty percent fly ash caused a higher increase in growth and yield than did 20%. Sixty percent, 80% and 100% fly ash had an adverse effect on growth and yield of all the three cultivars, the maximum being with 100% fly ash. Inoculation of H. oryzae had an adverse effect on the growth and yield, Pant-10 suffered higher damage by H. oryzae than Pusa Basmati and Pant-4. Pant-10 also exhibited higher infected leaf area and greater disease symptoms of H. oryzae than did Pusa Basmati and Pant-4. Plants grown in 100% fly ash suffered higher reductions in growth and yield with H. oryzae than plants grown in pure soil or in 20% or 40% fly ash. In general, plant growth was best in Pusa Basmati followed by Pant-4 and Pant-10, while yield was higher in Pant-4 followed by Pant-10 and Pusa Basmati.

Agriculture↗
PubMed2003

Effect of fly ash, organic wastes and chemical fertilizers on yield, nutrient uptake, heavy metal content and residual fertility in a rice-mustard cropping sequence under acid lateritic soils.

A field experiment was conducted for two years in sandy loam acid lateritic soil to study the direct effect of fly ash, organic wastes and chemical fertilizers on rice (Oryza sativa) and their residual effect on mustard (Brassica napus var glauca) grown in sequence. Rice yields were higher when fly ash, organic wastes and chemical fertilizers were used in an integrated manner as compared to sole application of chemical fertilizers. Yields of mustard were also higher under the residual effect of the former rather than the latter. However, this beneficial residual effect under integrated nutrient sources was inadequate for the mustard crop in the low fertility test soil. Hence, direct application of fertilizers was needed, in addition to residual fertility. The effect of fly ash on mean rice equivalent yield of the rice-mustard cropping sequence was highest (up to 14%) when it was used in combination with organic wastes and chemical fertilizers. While the yield increase was 10% when it was used in combination with only chemical fertilizers. The minimum yield advantage, 3%, occurred when fly ash was applied alone. The equivalent yield of the rice-mustard cropping sequence was equally influenced by either of the organic wastes. Cadmium and Ni content in rice grain and straw were less under the direct effect of fly ash. The residual effect on mustard was similar for Ni content in seed and stover; however, Cd content was increased. Beneficial residual soil chemical properties in terms of pH, organic carbon and available N, P and K were noted for integrated nutrient treatments involved fly ash, organic wastes and chemical fertilizers as compared to continuous use of only chemical fertilizers. Application of fly ash alone was effective in raising soil available P. Thus, integrated use of fly ash, organic wastes and chemical fertilizers was beneficial in improving crop yield, soil pH, organic carbon and available N, P and K in sandy loam acid lateritic soil.

Agriculture↗
PubMed1990

Milk yield and mammary function in dairy cows milked four times daily.

Groups of lactating cows and heifers were milked four times daily in two diagonally opposed glands for 4 weeks, and the effects on milk yield studied relative to twice-daily milked glands as controls. Mammary enzyme activities, in vitro synthesis rates of milk constituents and histological scoring were determined in mammary biopsy samples obtained at the end of this period. These were used for assessment of mammary function. Frequent milking increased milk yield only in the treated glands, the contralateral control glands continuing to decline in yield at approximately 2%/week. There was no significant difference in response between cows and heifers; the mean increase in yield was 10.4%. The rate of decline in milk yield tended to decrease with frequent milking, to approximately 1%/week. Consequently the yield of the treated glands continued to be elevated above that of the controls for some time after reversion to overall twice daily milking. Milk protein content was increased slightly by frequent milking. Mammary enzyme activities were approximately 18% higher in the treated glands than in the controls. Synthesis rates of lactose, casein and total protein were unaffected by milking frequency, but were all lower in the gland selected for the second biopsy, reflecting the reduction in milk yield caused by the first biopsy. DNA synthesis was increased by milking frequency, as were the size and number of epithelial cells in histological sections.

Animals↗
PubMed1990

A method for assessing loss in milk yield due to subclinical mastitis.

A method for assessing the loss in quarter milk yield due to subclinical mastitis is proposed. It is based upon two indices calculated from quarter milk yields and results from the assessment of mastitis obtained by measurement of the electrical conductivity of milk. The results were obtained from the cows through repeated quarter-milkings during several months of lactation. The grade of abnormality of a quarter with subclinical mastitis was expressed by the first index, the mean quarter difference of electrical conductivity of milk produced by the quarter (mQdEC, 25 degrees C). The reduction in milk yield of a quarter presumed to be due to subclinical mastitis was expressed by another index, the quarter yield ratio, R, which is that percentage of normal milk yield produced by a quarter with mastitis. Examination of the relationship between these two indices showed that subclinical mastitis caused a reduction in milk yield in the affected quarters. From the linear regression, it was found that approximately 3% reduction in quarter milk yield occurred for every 1 X 10(-4)S/cm increase in the mQdEC of the quarter with presumed subclinical mastitis.

Animals↗
PubMed1994

Once daily milking of dairy cows: relationship between yield loss and cisternal milk storage.

The proportions of milk stored in the gland cistern (cisternal) and within secretory alveolar tissue (alveolar) were determined for a group of ten cows in mid lactation, yielding approximately 20 kg milk/d. As a proportion of total milk, cisternal milk, measured at 8 h after milking, ranged from 0.09 to 0.53. Milking frequency was then reduced from twice daily to once daily on two occasions, first for 1 week and then, 2 weeks later, for 2 weeks. Milk yield was reduced during once daily milking in all cows, by an average of 22.8% during the first week (P < 0.001). The amount of decrease varied among cows in a way that was unrelated to pretreatment yield, but the immediate decrease was significantly and inversely correlated with cisternal milk proportion (r = 0.81, P < 0.01). When milking reverted to twice daily, yield recovered to a value not significantly different from pretreatment, and the degree of recovery was inversely related to cisternal milk proportion (r = 0.74, P < 0.01). With the exception of one cow, yield decreases correlated well between the two periods of once daily milking. When treatment weeks were disregarded, lactation persistency (the rate of decline in yield with time) was unaffected by once daily milking. The results show that the ability of individual cows to tolerate once daily milking is related to their cisternal storage characteristics; yield is reduced less in cows that store a greater proportion of their total milk production within the cistern.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2006

Effects of length of dry period on yields of milk fat and protein, fertility and milk somatic cell score in the subsequent lactation of dairy cows.

The objective was to utilize data from modern US dairy cattle to determine the effect of days dry on fat and protein yield, fat and protein percentages, days open, and somatic cell score in the subsequent lactation. Field data collected through the dairy herd improvement association from January 1997 to December 2003 and extracted from the Animal Improvement Programs Laboratory national database were used for analysis. Actual lactation records calculated from test-day yields using the test-interval method were used in this study. The model for analyses included herd-year of calving, year-state-month of calving, previous lactation record, age at calving, and days dry as a categorical variable. Fat and protein yield was maximized in the subsequent lactation with a 60-d dry period. Dry periods of 20 d or less resulted in substantial losses in fat and protein yield in the subsequent lactation. In contrast to yields, a short dry period was beneficial for fat and protein percentages. Short dry periods also resulted in fewer days open in the subsequent lactation; however, this was entirely due to the lower milk yield associated with shortened dry period. When adjusted for milk yield, short dry periods actually resulted in poorer fertility in the subsequent lactation. Long days dry improved somatic cell score in the subsequent lactation. Herds with mastitis problems should be cautious in shortening days dry because short dry periods led to higher cell scores in the subsequent lactation compared with 60-d dry.

Animals↗
PubMedDate not supplied

Effects of pressing lignocellulosic biomass on sugar yield in two-stage dilute-acid hydrolysis process.

Dilute sulfuric acid catalyzed hydrolysis of biomass such as wood chips often involves pressing the wood particles in a dewatering step (e.g., after acid impregnation) or in compression screw feeders commonly used in continuous hydrolysis reactors. This study addresses the effects of pressing biomass feedstocks using a hydraulic press on soluble sugar yield obtained from two-stage dilute-acid hydrolysis of softwood. The pressed acid-impregnated feedstock gave significantly lower soluble sugar yields than the never-pressed (i.e., partially air-dried or filtered) feedstock. Pressing acid-impregnated feedstocks before pretreatment resulted in a soluble hemicellulosic sugar yield of 76.9% from first-stage hydrolysis and a soluble glucose yield of 33.7% from second-stage hydrolysis. The dilute-acid hydrolysis of partially air-dried feedstocks having total solids and acid concentrations similar to those of pressed feedstocks gave yields of 87.0% hemicellulosic sugar and 46.9% glucose in the first and second stages, respectively. Microscopic examination of wood structures showed that pressing acid-impregnated wood chips from 34 to 54% total solids (TS) did not cause the wood structure to collapse. However, pressing first-stage pretreated wood chips (i.e., feedstock for second-stage hydrolysis) from approximately 30 to 43% TS caused the porous wood matrix to almost completely collapse. It is hypothesized that pressing alters the wood structure and distribution of acid within the cell cavities, leading to uneven heat and mass transfer during pretreatment using direct steam injection. Consequently, lower hydrolysis yield of soluble sugars results. Dewatering of corn stover by pressing did not impact negatively on the sugar yield from single-stage dilute-acid pretreatment.

Acids↗
PubMed2002

Influence of yield and maturation index on polysaccharides and other compounds of grape juice.

Wine producers may attempt to increase vine productivity, which usually decreases the quality. The quality of Cava (Spanish sparkling wine; Certified Brand of Origin in Spain) mainly depends on the composition of its colloids, which also determine foam quality. The yield (kg of grape/ha) and maturation index (ratio between soluble solids and titratable acidity) are two external factors that may alter grape characteristics, especially its composition. Twenty white grapes of the same variety (Parellada), but different yields (between 6000 and 17,000 kg/ha) were studied. By PCA, two grape groups were separated according to yield (<10,500 and >10,500 kg/ha). Yield and maturation index were not significantly correlated. Grapes obtained with yield >10,500 kg/ha had significantly higher content of soluble proteins and lower content of total polysaccharides and some polysaccharides fractions (M(r) 62,000-48,000, M(r) 28,000-24,000, and M(r) 7000-5000) than the grapes of the low-yield group (<10 500 kg/ha). Thus, it may be interesting to monitor yield, below 10 500 kg/ha, in vines used to produce Cava.

Beverages↗
PubMedDate not supplied

Ozonation of methyl oleate in hexane, in a thin film, in SDS micelles, and in distearoylphosphatidylcholine liposomes: yields and properties of the Criegee ozonide.

We here explore the use of Criegee ozonides as markers of ozone damage to lipids in systems that model pulmonary surfactant, lung lining fluids, and/or pulmonary membranes. Ozonation of methyl oleate in hexane gives an 89% yield of the Criegee ozonide. The presence of water should reduce the yield of this ozonide, and as expected, small but significant yields of Criegee ozonides are formed when the ozonation of methyl oleate is carried out as a film over phosphate buffer, in aqueous micelles of sodium dodecyl sulfate (SDS), or in distearoyl-L-alpha-phosphatidylcholine (DSPC) liposomes spiked with methyl oleate. Analysis utilizes reversed-phase HPLC and 1H NMR. The total yield of ozonides in 0.02 M SDS micelles exposed to 26 ppm ozone for 3 h at pH 7.4 and 22 degrees C is 11%; 7.5% is the normal ozonide, methyl 5-octyl-1,2,4-trioxolane-3-octanoate (MOO2) (ca. 4.2% trans and ca. 3.3% cis), and 3.5% is accounted for by the two cross ozonides, 3,5-dioctyl-1,2,4-trioxolane (MOO1) and dimethyl 1,2,4-trioxolane-3,5-dioctanoate (MOO3). No significant difference of ozonide yields is observed for ozonations with 26 ppm and 1.2% (12,000 ppm) ozone. The conversion of methyl oleate increaes with increasing SDS concentration. Approximately comparable yields of ozonides also are found in the ozonation of methyl oleate in DSPC liposomes although yields are not quantified. The ozonides slowly hydrolyze at pH 7.4 and 37 degrees C with half-lives for trans-MOO2 and cis-MOO2 in 0.10 M SDS micelles of 23 and 6 days, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromatography, High Pressure Liquid↗
PubMed1996

Estimation of the progenitor cell yield in a leukapheresis product by previous measurement of CD34+ cells in the peripheral blood.

To assess whether measurement of CD34+ cells in the peripheral blood allows one to estimate the progenitor cell yields of subsequent leukapheresis procedures, 733 corresponding blood and leukapheresis samples were analyzed. Peripheral blood progenitor cells of cancer patients were mobilized with hematopoietic growth factors alone or postchemotherapy, and harvested processing 10 liters of blood for each leukapheresis product. The CD34+ cell count (CD34+ cells/microliter blood) correlated most closely with the progenitor cell yield in the corresponding leukapheresis product (CD34+ cells/kg bodyweight, r = 0.80), while the proportion of circulating CD34+ cells to the white blood and mononuclear cells predicted the yield less reliably (r = 0.74 and r = 0.60). The CD34+ cell yield was independent of the white blood count (r = 0.04), whereas a weak correlation was found between the mononuclear cell count and the number of CD34+ cells/kg collected (r = 0.42). It was unlikely to obtain the threshold quantity of 2.5 x 10(6) CD34+ cells/kg required for rapid engraftment when counts below 10 CD34+ cells/microliter blood were detected. At levels between 10 and 30 CD34+ cells/microliter sufficient autografts could be harvested, whereas 30-100 CD34+ cells/microliter were required to achieve this by a single leukapheresis. A surplus of CD34+ cells was likely above 100 CD34+ cells/microliter which could be useful for progenitor cell enrichment techniques. The correlation between the CD34+ cell count and progenitor cell yield was independent of the mobilizing regimen and whether leukaphereses had been performed previously. In conclusion, the number of CD34+ cells/microliter blood allows a reliable prediction of the CD34+ progenitor cell yield in subsequent leukapheresis procedures. However, rare cases of unexpectedly sufficient progenitor cell yields may be observed even at CD34+ cell levels below detection limit.

Adolescent↗
PubMedDate not supplied

Effects of level and type of energy source (volatile fatty acids or glucose) on milk yield, composition and coagulating properties in dairy cows.

Four fistulated Holstein cows were arranged in a 4 x 4 Latin square design to study the effects of level and type of energy source on milk yield and composition. Treatments consisted of a basal diet fed alone (low energy treatment) or with 3.3 Mcal of net energy for lactation from extra nutrients perfused either into the rumen (either propionic acid or a mixture of volatile fatty acids) or into the duodenum (glucose). Increasing the energy input without changing the volatile fatty acid profile improved milk yield and slightly increased milk protein and fat yields. Compared with the isoenergetic mixture of volatile fatty acids, both propionic acid and glucose infusions significantly decreased fat content (-4.5 g/kg) and yields (respectively, -111 and -160 g/d), but affected fatty acid proportion and yield differently (more elongation process and less C18 with glucose infusion). Protein yield was slightly increased by propionic acid infusion but not by glucose because of the counterbalanced effects on milk yield (-1.3 kg/d) and protein content (1.5 g/kg). The coagulating properties of milk were directly linked to variations in protein, casein and mineral contents. In conclusion, propionic acid or glucose scarcely affected milk protein content, but induced a similar decrease in milk fat content probably through different metabolic pathways.

3-Hydroxybutyric Acid↗
PubMed1989

"Low yield" cigarettes and the risk of nonfatal myocardial infarction in women.

Newer brands of cigarettes with reduced yields of nicotine and carbon monoxide have been promoted as being less hazardous than others. We evaluated the effect of smoking "low yield" cigarettes on the risk of nonfatal myocardial infarction in women under 65 years of age. The data were obtained in a case-control study of 910 women with a first myocardial infarction and 2375 hospital controls. The estimated relative risk for current smokers as compared with those who had never smoked increased with the number of cigarettes smoked. The estimated overall relative risk was 3.7 (95 percent confidence interval, 3.0 to 4.7). The estimated risks did not vary according to the nicotine or carbon monoxide yield of the cigarette. The estimated relative risk (4.7) in women who smoked brands with the lowest levels of nicotine (less than 0.40 mg per cigarette) was similar to that (4.2) in smokers of the higher-yield brands (greater than 1.30 mg). For exsmokers, the estimated relative risk was 1.4 (95 percent confidence interval, 1.0 to 1.8). These data suggest that women who smoke low-yield cigarettes do not have a lower risk of a first nonfatal myocardial infarction than women who smoke higher-yield brands. For smokers who wish to reduce their risk, switching to low-yield brands is a poor alternative to quitting.

Adult↗
PubMed2004

A study of the static yield stress in a binary Lennard-Jones glass.

The stress-strain relations and the yield behavior of a model glass (a 80:20 binary Lennard-Jones mixture) is studied by means of molecular dynamics simulations. In a previous paper it was shown that, at temperatures below the glass transition temperature, Tg, the model exhibits shear banding under imposed shear. It was also suggested that this behavior is closely related to the existence of a (static) yield stress (under applied stress, the system does not flow until the stress sigma exceeds a threshold value sigmay). A thorough analysis of the static yield stress is presented via simulations under imposed stress. Furthermore, using steady shear simulations, the effect of physical aging, shear rate and temperature on the stress-strain relation is investigated. In particular, we find that the stress at the yield point (the "peak"-value of the stress-strain curve) exhibits a logarithmic dependence both on the imposed shear rate and on the "age" of the system in qualitative agreement with experiments on amorphous polymers, and on metallic glasses. In addition to the very observation of the yield stress which is an important feature seen in experiments on complex systems like pastes, dense colloidal suspensions and foams, further links between our model and soft glassy materials are found. An example is the existence of hysteresis loops in the system response to a varying imposed stress. Finally, we measure the static yield stress for our model and study its dependence on temperature. We find that for temperatures far below the mode coupling critical temperature of the model (Tc = 0.435 in Lennard-Jones units), sigmay decreases slowly upon heating followed by a stronger decrease as Tc is approached. We discuss the reliability of results on the static yield stress and give a criterion for its validity in terms of the time scales relevant to the problem.

Journal Article↗
PubMed2004

Rice yields decline with higher night temperature from global warming.

The impact of projected global warming on crop yields has been evaluated by indirect methods using simulation models. Direct studies on the effects of observed climate change on crop growth and yield could provide more accurate information for assessing the impact of climate change on crop production. We analyzed weather data at the International Rice Research Institute Farm from 1979 to 2003 to examine temperature trends and the relationship between rice yield and temperature by using data from irrigated field experiments conducted at the International Rice Research Institute Farm from 1992 to 2003. Here we report that annual mean maximum and minimum temperatures have increased by 0.35 degrees C and 1.13 degrees C, respectively, for the period 1979-2003 and a close linkage between rice grain yield and mean minimum temperature during the dry cropping season (January to April). Grain yield declined by 10% for each 1 degrees C increase in growing-season minimum temperature in the dry season, whereas the effect of maximum temperature on crop yield was insignificant. This report provides a direct evidence of decreased rice yields from increased nighttime temperature associated with global warming.

Biomass↗
PubMed1981

Photosensitized electron transfer processes in SiO(2) colloids and sodium lauryl sulfate micellar systems: Correlation of quantum yields with interfacial surface potentials.

The effectiveness of negatively charged colloidal SiO(2) particles in controlling photosensitized electron transfer reactions has been studied and compared with that of the negatively charged sodium lauryl sulfate (NaLauSO(4)) micellar system. In particular, the photosensitized reduction of the zwitterionic electron acceptor propylviologen sulfonate (PVS(0)) with tris(2,2'-bipyridinium)ruthenium(II) [Ru(bipy)(3) (2+)] as the sensitizer and triethanolamine as the electron donor is found to have a quantum yield of 0.033 for formation of the radical anion (PVS([unk])) in the SiO(2) colloid compared with 0.005 in the homogeneous system and 0.0086 in a NaLauSO(4) micellar solution. The higher quantum yields obtained with the SiO(2) colloidal system are attributed to substantial stabilization against back reaction of the intermediate photoproducts-i.e., Ru(bipy)(3) (3+) and PVS([unk])-by electrostatic repulsion of the reduced electron acceptor from the negatively charged particle surface. The binding properties of the SiO(2) particles and NaLauSO(4) micelles were investigated by flow dialysis. The results show that the sensitizer binds to both interfaces and that the SiO(2) interface is characterized by a much higher surface potential than the micellar interface ( approximately -170 mV vs. -85 mV). The effect of ionic strength on the surface potential was estimated from the Gouy-Chapman theory, and the measured quantum yields of photosensitized electron transfer were correlated with surface potential at different ionic strengths. This correlation shows that the quantum yield is not affected by surface potentials smaller than approximately -40 mV. At larger potentials, the quantum yield increases rapidly. The quantum yield obtained in the micellar system at different strengths fits nicely on the correlation curve for the colloid SiO(2) system. These results indicate that the surface potential is the dominant factor in the quantum yield improvement for PVS(0) reduction.

Journal Article↗
PubMed2006

Effect of gamma irradiation on the grain yield of Nigerian Zea mays and Arachis hypogaea.

As a follow-up to our earlier investigation on the effect of gamma radiation on the germination and growth of certain Nigerian agricultural crops, the present study sought to determine the effect of gamma radiation on the grain yield of Zea mays (maize) and Arachis hypogaea (groundnut). The seeds were planted after irradiation without the application of fertiliser. The results show that for maize, grain yield for irradiated samples is increased to levels above the unirradiated yield at doses up to about 250 Gy with the optimum yield occurring at 150 Gy. The corresponding increase for groundnut is observed at doses up to about 930 Gy with optimum yield at a dose of 300 Gy. Inhibition in yield was observed to set in at a dose greater than 250 Gy for maize and 930 Gy for groundnut. The actual relationship between mean yield of these crops and gamma radiation dose was obtained using sixth-degree polynomial equations.

Agriculture↗
PubMed1987

Nitric oxide yields of contemporary UK, US and French cigarettes.

To determine what governs nitric oxide (NO) yields of cigarettes and to obtain a range of yields for contemporary cigarettes 17 UK, 14 US, 8 French and 1 Turkish brand were analysed using a chemiluminescent analyser and standard smoking machine. The country of origin appeared to be the major factor affecting NO yield. US and French brands exceeded UK values by 3-5 fold. Apart from a reduced NO yield in UK ventilated filtered brands, the design of a cigarette and its tar, nicotine and carbon monoxide (CO) yield had little effect on NO yield. It is argued that these international differences in NO yields reflect differences in the nitrate content of tobaccos traditionally used in manufacture in those countries over many years. Despite their probable increased lifetime exposure to NO (and by implication nitrosamine exposure) there appears to be little evidence that US and French smokers are at greater risk of lung disease than their UK counterparts.

Carbon Monoxide↗