Effect of hypocapnia on the sensitivity of hyperthermic hyperventilation and the cerebrovascular response in resting heated humans

Elevating core temperature at rest causes increases in minute ventilation (V̇e), which lead to reductions in both arterial CO2 partial pressure (hypocapnia) and cerebral blood flow. We tested the hypothesis that in resting heated humans this hypocapnia diminishes the ventilatory sensitivity to rising core temperature but does not explain a large portion of the decrease in cerebral blood flow. Fourteen healthy men were passively heated using hot-water immersion (41°C) combined with a water-perfused suit, which caused esophageal temperature (Tes) to reach 39°C. During heating in two separate trials, end-tidal CO2 partial pressure decreased from the level before heating (39.4 ± 2.0 mmHg) to the end of heating (30.5 ± 6.3 mmHg) (P = 0.005) in the Control trial. This decrease was prevented by breathing CO2-enriched air throughout the heating such that end-tidal CO2 partial pressure did not differ between the beginning (39.8 ± 1.5 mmHg) and end (40.9 ± 2.7 mmHg) of heating (P = 1.00). The sensitivity to rising Tes (i.e., slope of the Tes − V̇E relation) did not differ between the Control and CO2-breathing trials (37.1 ± 43.1 vs. 16.5 ± 11.1 l·min−1·°C−1, P = 0.31). In both trials, middle cerebral artery blood velocity (MCAV) decreased early during heating (all P < 0.01), despite the absence of hyperventilation-induced hypocapnia. CO2 breathing increased MCAV relative to Control at the end of heating (P = 0.005) and explained 36.6% of the heat-induced reduction in MCAV. These results indicate that during passive heating at rest ventilatory sensitivity to rising core temperature is not suppressed by hypocapnia and that most of the decrease in cerebral blood flow occurs independently of hypocapnia

Additional file 2: of Meteorological factors affecting dengue incidence in Davao, Philippines

Figure S2. Weekly distribution of dengue incidence, average temperature, and cumulative rainfall from 2011 to 2015 in Davao Region. Red line is the cumulative rainfall, dotted blue line are the dengue incidences, and the green dot-and-line is the average temperature. The right-hand side y-axis is in degrees Celsius (for the average temperature), while the left-hand side y-axis is for the dengue incidence and rainfall levels. (JPEG 38 kb

Additional file 1: of Meteorological factors affecting dengue incidence in Davao, Philippines

Table S1. Sensitivity analysis with the combination of DLNM and simple linear models. The table depicts that no matter the combination of the linear and DLNM models, there is not much improvement in the model performance, with similar observations in the previous univariate linear and DLNM models. (DOCX 14 kb

Additional file 5: of Meteorological factors affecting dengue incidence in Davao, Philippines

Figure S4. EF-applied dose-response risk curve. Relatively the same risk patterns can be observed, with heightened risks for moderate rain, low temperature and high dew point. (TIFF 1551 kb

Additional file 4: of Meteorological factors affecting dengue incidence in Davao, Philippines

Figure S1. Annual distribution of cumulative rainfall (mm) in Davao Region, 2011–2015. Annual variations in the rainfall, with 2012 recording the highest level (of rainfall). (TIFF 6784 kb

Additional file 3: of Meteorological factors affecting dengue incidence in Davao, Philippines

Figure S3. Distribution of monthly dengue incidences and local meteorological variables from 2011 to 2015. (A) Box plot of the monthly dengue incidences, (B) Average temperature (°C), (C) Cumulative rainfall (mm), and (D) Dew point (°C). The horizontal line in the middle of each box is the mean, while the top and bottom borders of the box represent the 25th and 75th percentiles, respectively and the whiskers indicates the 10th and 90th percentiles. (TIF 234 kb

Excitation Spectra of Cation and Anion Radicals of Several Unsaturated Hydrocarbons: Symmetry Adapted Cluster-Configuration Interaction Theoretical Study

Excitation spectra of cation and anion radicals of unsaturated hydrocarbons, hexatriene^±, octatetraene^±, cyclopentadiene⁺, 1,3-cyclohexadiene⁺, and naphthalene^±, were studied by the symmetry adapted cluster-configuration interaction (SAC-CI) method. The calculated results reasonably reproduced the experimental spectra observed by one of the authors (T.S.) and gave reasonable assignments. The two bands observed in the experimental spectra were assigned to π–π_SOMO and π_SOMO–π* for the cation radicals and π*_SOMO–π* and π–π*_SOMO for the anion radicals, in order of increasing energy, except for naphthalene^±. The four bands of naphthalene⁺ originated from π–π_SOMO, π–π_SOMO, π_SOMO–π*, and π_SOMO–π* and those of naphthalene^– originated from π*_SOMO–π*, π*_SOMO–π*, π–π*_SOMO, π*_SOMO–vπ*, and π–π*_SOMO, in order of increasing energy. The SOMO orbitals were involved in the intense bands of both cation and anion radicals. Moreover, the ionization energies (IEs) and electron affinities (EAs) of these hydrocarbons were in good agreement with the experimental values, whereas the EAs of hexatriene and octatetraene were predicted to be negative and positive, respectively. The calculated IE + EA values were nearly constant for the three π–π* pairing states of hexatriene^±, octatetraene^±, and naphthalene^±, indicating that the pairing theorem is valid even at the SAC-CI level

Reply to Parkes: Effect of hypocapnia on the sensitivity of hyperthermic hyperventilation and the cerebrovascular response in resting heated humans

Reply to Parkes: Effect of hypocapnia on the sensitivity of hyperthermic hyperventilation and the cerebrovascular response in resting heated human

City-combined association between daily mean O₃ (lag0-1, ppb) and daily mortality adjusted for PM₁₀ in 13 Japanese and Korean cities from 2000 to 2009.

<p>City-combined association between daily mean O₃ (lag0-1, ppb) and daily mortality adjusted for PM₁₀ in 13 Japanese and Korean cities from 2000 to 2009.</p

Thresholds of concentration-response relationship between O₃ concentration and daily mortality and the excessive mortality for 1 ppb increment below and above the thresholds adjusting for PM₁₀ in 7 Japanese and Korean cities.

<p>Thresholds of concentration-response relationship between O₃ concentration and daily mortality and the excessive mortality for 1 ppb increment below and above the thresholds adjusting for PM₁₀ in 7 Japanese and Korean cities.</p