Morning Increase Research Articles

Circadian rhythms in pump parameters of patients on contemporary left ventricular assist device support.

Algorithms to monitor pump parameters are needed to further improve outcomes after left ventricular assist device (LVAD) implantation. Previous research showed a restored circadian rhythm in pump parameters in patients on HeartWare (HVAD) support. Circadian patterns in HeartMate3 (HM3) were not studied before, but this is important for the development of LVAD monitoring algorithms. Hence, we aimed to describe circadian patterns in HM3 parameters and their relation to patterns in heart rate (HR). 18 HM3 patients were included in this study. HM3 data were retrieved at a high frequency (one sample per 1 or 2 h) for 1-2 weeks. HR was measured using a wearable biosensor. To study overall patterns in HM3 parameters and HR, a heatmap was created. A 24-h cosine was fitted on power and HR separately. The relationship between the amplitude of the fitted cosines of power and HR was calculated using Spearman correlation. A lower between patient variability was found in power compared with flow and PI. 83% of the patients showed a significant circadian rhythmicity in power (p < 0.001-0.04), with a clear morning increase. All patients showed significant circadian rhythmicity in HR (p < 0.001-0.02). The amplitudes of the circadian rhythm in power and HR were not correlated (Spearman correlation of 0.32, p = 0.19). A circadian rhythm of pump parameters is present in the majority of HM3 patients. Higher frequency pump parameter data should be collected, to enable early detection of complications in the future development of predictive algorithms.

EARLY MORNING HEMODYNAMIC CHANGES AND LEFT VENTRICULAR HYPERTROPHY AND MORTALITY IN HEMODIALYSIS PATIENTS

Objective: Amplified early morning increase in BP, a phenomenon accompanied by a parallel rise in heart rate (HR), is a marker of high cardiovascular risk in the general population. The early morning changes in these parameters have not been investigated in the hemodialysis population. Design and method: In a pilot, single center, study including a series of 58 hemodialysis patients we measured the pre-awakening BP and HR surges and the nocturnal dipping of the same parameters as well as other established indicators of autonomic function (weighted 24h systolic BP and HR variability) and tested their relationship with the left ventricular mass index (LVMI) and with the risk of death over a median follow up of 40 months. Results: The pre-awakening HR surge (r = -0.46, P = 0.001) was inversely associated with LVMI and the risk of death [HR (1 unit): 0.89, 95% CI: 0.83-0.96, P = 0.001] while the corresponding BP surge largely failed to associate with these outcomes. The link between the pre-awakening HR surge with LVMI and death was robust and largely independent of established risk factors in the hemodialysis population, including the nocturnal dipping of BP. Weighted 24h systolic BP and HR variability did not correlate with LVMI (all P&gt;0.11) nor with the risk of death (P&gt;0.11) and these parameters were also independent of the nocturnal dipping of systolic BP and HR. Conclusions: This pilot study suggests that the low early morning changes in HR, likely reflecting enhanced sympathetic activity, entail a high risk for LVH and mortality in the hemodialysis population.

Concurrent measurements of atmospheric ammonia concentrations in the megacities of Beijing and Shanghai by using cavity ring-down spectroscopy

Ammonia (NH3) is a vital precursor of secondary aerosols, which play an important role in urban air pollution. The passive observation of NH3 in the urban atmosphere showed higher concentrations than conventionally believed; however, the NH3 dynamics remain limited due to the paucity of active measurements with fast response instruments. In this study, intensive online measurements of ambient NH3 were conducted using cavity ring-down spectroscopy in late spring and early summer 2020 at the megacities of Beijing and Shanghai in northern and southern China. The results show that the average NH3 concentration in Beijing (23.1 ± 10.3 ppb) was nearly double that in Shanghai (12.0 ± 5.0 ppb). This spatial difference was confirmed by satellite column observations and bottom-up emission patterns. In addition, there was a significant increase in NH3 concentrations during the morning in our study. This special diurnal profile was a universal feature, with an occurrence frequency exceeding 50% in both cities. These frequent morning increases were mainly caused by motor vehicle emissions, with an additional contribution from the residual layer breakup for one-quarter of the days in the morning increase. On these days, the NH3 concentration increased by approximately 20% due to the downward mixing of the residual layer rupture. The unique data observed here could be used to validate the chemistry and transport models at a higher time resolution and improve the understanding of the current status of NH3 pollution in the urban atmosphere.

EARLY MORNING HEMODYNAMIC CHANGES AND LEFT VENTRICULAR HYPERTROPHY AND MORTALITY IN HEMODIALYSIS PATIENTS

Objective: An exaggeration of the early morning increase in BP, a phenomenon accompanied by a parallel rise in heart rate (HR), is a marker of high cardiovascular risk. The early morning changes in these parameters have not been investigated in the hemodialysis population. Design and method: In a pilot, single center, study including a series of 58 patients we measured the pre-awakening BP and HR surges and the nocturnal dipping of the same parameters as well as other established indicators of autonomic function (weighted 24 h systolic BP and HR variability) and tested their relationship with the left ventricular mass index (LVMI) and with the risk of death over a median follow up of 40 months. Results: The pre-awakening HR surge (r = -0.46, P = 0.001) but not the corresponding BP surge (r = -0.1, P = 0.98) associated with LVMI and the risk of death [HR (1 unit): 0.89, 95% CI: 0.83–0.96, P = 0.001]. The link between the pre-awakening HR surge with these outcome measures was robust and largely independent of established risk factors in the hemodialysis population including the systolic BP dipping. Weighted 24 h systolic BP (SD) and HR (SD) variability did not correlate with LVMI (all P&gt; 0.11) nor with the risk of death (P &gt; 0.11). Overall, among markers of early morning hemodynamic changes and of hemodynamic variability, the pre-awakening HR surge was the strongest correlate of LVMI and a the strongest predictor of death. Conclusions: This pilot study suggests that low early morning changes in HR, a biomarker reflecting sympathetic activity, entail a high risk for LVH and mortality in the hemodialysis population.

MO858: Early Morning Haemodynamic Changes and Left Ventricular Hypertrophy and Mortality In Haemodialysis Patients

Abstract BACKGROUND AND AIMS Amplified early morning increase in BP, a phenomenon accompanied by a parallel rise in heart rate (HR), is a marker of high cardiovascular risk in the general population. The early morning changes in these parameters have not been investigated in the haemodialysis population. METHOD In a pilot, single centre, study including a series of 58 haemodialysis patients we measured the pre-awakening BP and HR surges and the nocturnal dipping of the same parameters as well as other established indicators of autonomic function (weighted 24h systolic BP and HR variability) and tested their relationship with the left ventricular mass index (LVMI) and with the risk of death over a median follow up of 40 months. RESULTS The pre-awakening HR surge (r = –0.46; P = 0.001) was inversely associated with LVMI and the risk of death [HR (1 unit): 0.89, 95% confidence interval: 0.83–0.96; P = 0.001] while the corresponding BP surge largely failed to associate with these outcomes. The link between the pre-awakening HR surge with LVMI and death was robust and largely independent of established risk factors in the haemodialysis population, including the nocturnal dipping of BP. Weighted 24 h systolic BP and HR variability did not correlate with LVMI (all P &amp;gt; 0.11) nor with the risk of death (P &amp;gt; 0.11) and these parameters were also independent of the nocturnal dipping of systolic BP and HR. CONCLUSION This pilot study suggests that the low early morning changes in HR, likely reflecting enhanced sympathetic activity, entail a high risk for LVH and mortality in the haemodialysis population.

Early morning hemodynamic changes and left ventricular hypertrophy and mortality in hemodialysis patients.

An exaggeration of the early morning increase in BP, a phenomenon accompanied by a parallel rise in heart rate (HR), is a marker of high cardiovascular risk. The early morning changes in these parameters have not been investigated in the hemodialysis population. In a pilot, single center study including a series of 58 patients we measured the pre-awakening BP and HR surges and the nocturnal dipping of the same parameters as well as other established indicators of autonomic function (weighted 24h systolic BP and HR variability) and tested their relationship with the left ventricular mass index (LVMI) and with the risk of death over a median follow up of 40months. The pre-awakening HR surge (r = -0.46, P = 0.001) but not the corresponding BP surge (r = -0.1, P = 0.98) was associated with LVMI and the risk of death [HR (1 unit): 0.89, 95% CI 0.83-0.96, P = 0.001]. The link between the pre-awakening HR surge with these outcome measures was robust and largely independent of established risk factors in the hemodialysis population, including the nocturnal dipping of BP. Weighted 24h systolic BP and HR variability did not correlate with LVMI (all P > 0.11) nor with the risk of death (P > 0.11) and were also independent of the nocturnal dipping of systolic BP and HR. This pilot study suggests that the low early morning changes in HR, likely reflecting enhanced sympathetic activity, entail a high risk for left ventricular hypertrophy (LVH) and mortality in the hemodialysis population.

Diurnal Variation in Straylight in Patients With Fuchs Endothelial Corneal Dystrophy and Controls.

The goal of this study was to investigate diurnal changes in intraocular straylight in relation to other corneal parameters and subjective complaints in patients with Fuchs endothelial dystrophy and healthy controls. This is a prospective study conducted in 2 tertiary care hospitals in Germany and the Netherlands. Patients with Fuchs endothelial dystrophy (n = 71) and healthy controls (n = 34) were included. Patients with Fuchs dystrophy were grouped by the presence of subjective complaints and measured over multiple time points during the day. Measurements included intraocular straylight using the C-Quant and corneal thickness and backscatter using a Scheimpflug camera. A separate group of healthy controls was measured intensively with repeated straylight measurements directly after waking. An exponential decay model was used to model the diurnal change. Healthy controls showed an average straylight baseline of 1.17 log(s) with an increase in straylight after waking of 0.22 log(s). In the repeated measurements subgroup, the increase in morning straylight lasted for 22 minutes. Patients with Fuchs dystrophy showed a morning increase in straylight of 0.21 log(s) present up to 4 hours after waking before reaching an average baseline of 1.30 log(s). Straylight was positively correlated with anterior corneal backscatter, r = 0.21, P = 0.022, and corneal thickness, r = 0.46, P < 0.01. Healthy eyes experience a diurnal straylight increase similar to patients with Fuchs dystrophy in intensity. However, in Fuchs dystrophy, the resolution of increased straylight is prolonged over multiple hours compared with minutes in healthy eyes. This suggests pathological exacerbation of a physiological diurnal change. This mechanism can play a role in subjective complaints experienced by patients with Fuchs dystrophy.

Cortisol Awakening Reaction and Anxiety in Depressed Coronary Artery Disease Patients.

Disturbances of HPA axis functioning as represented by cortisol awakening reaction (CAR) belong to the mediating pathways linking psychosocial distress and cardiovascular risk. Both depression and anxiety have been confirmed as independent risk factors for coronary artery disease (CAD). However, data on anxiety and cortisol output in CAD patients are scarce. Based on previous data, we hypothesized that anxiety would be associated with higher cortisol output and a more pronounced morning increase in moderately depressed CAD patients. 77 patients (60 y, 79% male) underwent saliva sampling (+0, +30, +45, +60 min after awakening, midday and late-night sample). Anxiety was measured using the Hospital Anxiety and Depression Scale (HADS) and patients were grouped into anxious versus non anxious subjects based upon the recommended score (≥11). A repeated measures ANOVA yielded a significant time and quadratic time effect referring to the typical CAR. Anxious patients showed a significantly steeper 30 min increase, higher AUCi, lower waking and late-night cortisol levels. The steeper cortisol increase in the anxious group is in line with previous data and may be interpreted as a biological substrate of affect regulation. The lower basal and late-night levels coupled with greater AUCi mirror a more dynamic reactivity pattern compared to depressed subjects without anxiety.

Tall tower eddy covariance measurements of CO2 fluxes in Vienna, Austria

This study reports on three years (2018–2020) of turbulent CO2 fluxes measured at 144 m above the city of Vienna, Austria using an eddy covariance system installed on the A1 Arsenal radio tower. Overall CO2 flux data availability after quality control filtering (49%) was comparable to that observed by other studies of urban and suburban eddy covariance measurements. Average monthly CO2 fluxes followed seasonal trends in temperature-based proxies of heating demand, with the highest fluxes observed in the winter months. When analysing separate trends for the two dominating wind directions, this seasonality was most pronounced for the flows from the north-west when flux footprints overlapped with Vienna's most populated and urbanised districts and fluxes. For flows from the south-east, when flux footprints covered areas of built-up and industrial land yet were dominated by green urban spaces and arable land, the seasonality was much less marked and average monthly CO2 fluxes were generally lower, particularly in winter. Weekday-weekend patterns as well as weekday diurnal variations in CO2 generally followed respective trends in local traffic counts; however, flux correlations with hourly traffic counts on weekends and public holidays were much weaker. Weekend/public holiday diurnal trends in CO2 fluxes indicated an influence of vegetation fluxes on net CO2 flux variations between midday and late afternoon in spring and summer. Furthermore, variations in weekend/public holiday CO2 fluxes from night-time to morning periods suggested a partial night-time decoupling between turbulent exchange at 144 m and the net fluxes at the surface. While the influence of CO2 advection could not be quantified, the pronounced morning flux peaks indicated that CO2 released to the atmosphere during these partially decoupled, night-time periods accumulated to some extent and was subsequently mixed vertically with the morning increase in boundary layer depth. Indeed, the calculated annual fluxes suggested that positive and negative 30-min biases were largely offset when averaging over longer time intervals. The 2018 flux of 10.89 kt CO2 km−2 was in close agreement with the annual CO2 emissions estimate of 10.19 kt CO2 km−2 derived from an official emissions inventory (excluding large point source emissions). A similar annual flux was observed in 2019; however, the substantially lower flux in 2020 likely reflected emissions reductions associated with the COVID-19 pandemic. Comparison of normalised daytime CO2 fluxes between years indicated that the initial lockdown led to a ca. 50–60% reduction in net CO2 emissions from Vienna's most populated and urbanised districts. This study thus provides further evidence that defensible estimates of urban CO2 fluxes can be achieved with tall tower eddy covariance.

Indicators of ambulatory blood pressure monitoring in patients with essential hypertension of the 2-nd stage depending on the type of 24-hours blood pressure profile, the state of the left ventricular diastolic filling and endothelial function of vessels

Annotation. Arterial hypertension (AH) is one of the most important risk factors for the development of cardiovascular complications and mortality in the world and it has become a medical and social problem. The prevalence of hypertension will increase to 1.56 billion by 2025, making the disease a very serious problem. The severity of clinical manifestations and prognosis in patients with hypertension are determined not only by the degree of increase in blood pressure (BP) but also the damage to target organs. The load on the cardiovascular system caused by elevated BP leads to structural remodelling of the heart and vessels. The aim – to evaluate peculiarities of indicators of ambulatory blood pressure monitoring in patients with essential hypertension of the 2nd stage depending on the type of 24-hours blood pressure profile, the state of the left ventricular diastolic filling and endothelial function of the vessels and determine independent clinical and instrumental criteria of the 24-hours profile “dipper” and “non-dipper”. The study involved 110 patients (40 men and 70 women) with hypertension of the II-nd stage, hypertensive heart, chronic heart failure of the 0-I stage (average age was 54.19±0.89 years). The patients underwent 24-hour blood pressure monitoring, echocardiography and determination the thickness of the intima-media complex (IMCT) of the brachial artery, endothelium-dependent (EDVD) and endothelium-independent (EIVD) vasodilatation. For statistical analysis, arithmetic means (M), errors of mean values (m), t - Student's t test for paired measurements were calculated. Correlation ratios were evaluated by the method of linear correlation for parametric data and the method of Spearman’s rank correlation for nonparametric data. Paired group comparisons were performed by the nonparametric Mann-Whitney method. Wilcoxon test was used in the analysis of dependent samples. Step-by-step multifactor regression was used to identify independent criteria for daily blood pressure profiles. Two types of 24-hours profile of blood pressure – “dipper” and “non-dipper” were detected. The left ventricle diastolic dysfunction (LVDD) by type of relaxation disorder was observed in all “non-dipper” patients and most “dipper” patients. Patients with DD had higher levels of BP per 24-hours, day, night, corresponding the time indexes, the magnitude of the morning increase of systolic and diastolic blood pressure, more pronounced structural changes of the heart and vessels compared with patients with preserved diastolic filling of the LV(р&lt;0,01). The duration of the hypertensive anamnesis (p=0.0002), the thickness of the posterior wall of the LV (p=0.002), the maximum speed of early diastolic filling of the LV (E) (p&lt;0.0001), the LV ejection fraction (p=0.001), the index of the left atrium (p=0.008), the thickness of the intima-media complex of the brachial artery (p=0.013), increase of the diameter of the brachial artery in 90 s after compression (EDVD) (p&lt;0.0001) and in 5 min after taking of nitroglycerin (EIVD) (p=0.009) were determined as independent clinical and instrumental criteria of the “dipper” and “non-dipper” profile. Insufficient the degree of the nightly decrease of the BP, higher magnitude of the morning increase of systolic and diastolic BP cause more hemodynamic pressure on target organs and lead to more significant pathological remodeling of the LV and vessels, disorders of the LV relaxation processes and endothelial dysfunction.

Transient Variations of Total Electron Content (TEC) Over a Terrestrial Point within Magnetic Anomaly Region

This paper investigate the variability of Total Electron Content TEC over a terrestrial point within equatorial anomaly region using the NovAtel GSV 4000B GPS-SCINDA system at Akure (7.3°N, 5.2°E), Nigeria. This system is capable of tracking up to 14 GPS satellites simultaneously. Total Electron Content (TEC) over equatorial region using a real time data collected via a GPS-SCINDA facility were analyzed to study the ionospheric variations in terms of Total Electron Content (TEC) for the period of three years. Diurnal variations and Monthly mean variations of Total Electron Content within the equatorial anomaly region were examined. The diurnal variation of TEC showed pre-dawn minimum for a short period of time, followed by a steep early morning increase and then reached maximum value between 14:00 UT and 16:00 UT. The influence of solar activity on VTEC was investigated by taking the correlation coefficients between VTEC, F10.7cm radio flux index and sunspot numbers. The range of solar flux variation during the period of observation is very limited; there is high positive correlation (Correlation Coefficient 0.61) between daytime peak TEC and the solar F10.7 flux.

Hourly Variation of Wind Speeds in the Philippines and Its Potential Impact on the Stability of the Power System

Wind energy development has been limited by concerns associated to the varying features in wind speed which tends to destabilize the power system. This study aims to clarify the variability of winds within a day in the Philippines, specifically the hourly changes of onshore horizontal winds at 100-m hub-heights. A whole one-year experiment using the Weather Research and Forecasting model shows that onshore wind speeds decrease during the transitional hours between land breeze and sea breeze. The decreases in wind speed are most significant over coastal regions with high sloping topography. The extreme decreases in wind speed during morning hours, due to the natural processes, are found to often occur at the same time as the extreme electricity undersupply caused by the morning increase in energy demand. This result warns that the power system stability in the Philippines may become more sensitive to the variability of wind as the share of wind energy generation increases in the future. The findings of this study can contribute to promote sustainability in the operation of existing wind-reliant power systems and planning of future wind energy developments.

Circadian Rhythm of Blood Pressure of Dipper and Non-dipper Patients With Essential Hypertension: A Mathematical Modeling Approach

Blood pressure in humans presents a circadian variation profile with a morning increase, a small postprandial valley, and a deeper descent during night-time rest. Under certain conditions, the nocturnal decline in blood pressure can be reduced or even reversed (non-dipper), which is related to a significantly worse prognosis than a normal fall pattern (dipper). Despite several advances in recent years, our understanding of blood pressure's temporal structure, its sources and mechanisms is far from complete. In this work, we developed an ordinary differential equation-based mathematical model capable of capturing the circadian rhythm of blood pressure in dipper and non-dipper patients with arterial hypertension. The model was calibrated by means of global optimization, using 24-h data of systolic and diastolic blood pressure, physical activity, heart rate, blood glucose and norepinephrine, obtained from the literature. After fitting the model, the mean of the normalized error for each data point was <0.2%, and confidence intervals indicate that all parameters were identifiable. Sensitivity analysis allowed identifying the most relevant parameters and therefore inferring the most important blood pressure regulatory mechanisms involved in the non-dipper status, namely, increase in sympathetic over parasympathetic nervous tone, lower influence of physical activity on heart rate and greater influence of physical activity and glucose on the systemic vascular resistance. In summary, this model allows explaining the circadian rhythm of blood pressure and deepening the understanding of the underlying mechanisms and interactions integrating the results of previous works.

P1447EARLY MORNING ACCELERATION AND NOCTURNAL DECELERATION IN HEART RATE ASSOCIATE WITH LVH AND THE RISK OF DEATH AND CARDIOVASCULAR EVENTS IN HEMODIALYSIS PATIENTS

Abstract Background and Aims Cardiovascular deaths cluster in the early morning hours and studies in the general population documented that an exaggeration of the early morning increase in BP, a phenomenon accompanied by a parallel rise in heart rate (HR), is a marker of high cardiovascular risk. The circadian profile of BP and HR in hemodialysis patients is notoriously altered but the early morning changes in these parameters and the nocturnal profile of HR have not been investigated in this population. Method BP and HR were registered at 15 min intervals by ambulatory monitoring (24hABPM, Spacelab) during the day after hemodialysis in a series of 64 patients. We measured the early morning (the average of the 2 hours after awakening minus the average of the 2 hours pre-awakening) changes in BP and HR and the nocturnal decline in BP and HR and tested the relationship of these parameters with the left ventricular mass index (LVMI) and with the risk of all-cause and cardiovascular death over a median follow up of 40 months (Interquartile range 21-81) Results The rise in HR after awakening was strongly related in an inverse fashion with the LVMI (Spearman ρ=-0.61, P&amp;lt;001) suggesting that patients with a more pronounced increase in HR after awakening may be protected from LVH .Both, the decline in HR (ρ =-0.38, P=0.002) and in systolic BP (ρ =-0.31, P=0.01 ) during night-time associated inversely with LVMI. These associations remained significant also when they were reciprocally adjusted (P&amp;lt;0.01) in a model including also age, gender and simultaneous changes in BP. In contrast, the rise is systolic BP upon awakening had no relationship with the LVMI (ρ =0.18, P=0.18). Thirty-two deaths (16 cardiovascular) occurred during follow up. The early morning rise in HR was an inverse predictor of all cause death (HR=0.95; 95%CI 0.92-0.98 P=0.004 ) and of cardiovascular death (HR=0.95; 95%CI 0.91-0.98) in analyses adjusted for the simultaneous rise in systolic BP which per se failed to predict the same outcomes. Again, in similarity with analyses looking at LVMI, the nocturnal dipping in HR associated inversely with all cause and cardiovascular death (p=0.003). Conclusion The analysis of the nocturnal decline in HR and of the rise in HR increase upon awakening In hemodialysis patients reveals stronger links among these parameters and LVMI than the corresponding BP parameters. The protective effect on the left ventricle of a more pronounced HR rise upon awakening and of a more pronounced decline in HR during night time underscore the relevance of preserved autonomic function for cardiovascular protection in this population. These associations seem to go along with a reduced risk for all-cause and cardiovascular death. Analysis of the HR profile provides unique information for the risk of cardiomyopathy and cardiovascular events in the hemodialysis population.

Antagonistic Regulation of Circadian Output and Synaptic Development by JETLAG and the DYSCHRONIC-SLOWPOKE Complex

SummaryCircadian output genes act downstream of the clock to promote rhythmic changes in behavior and physiology, yet their molecular and cellular functions are not well understood. Here we characterize an interaction between regulators of circadian entrainment, output, and synaptic development in Drosophila that influences clock-driven anticipatory increases in morning and evening activity. We previously showed the JETLAG (JET) E3 ubiquitin ligase resets the clock upon light exposure, whereas the PDZ protein DYSCHRONIC (DYSC) regulates circadian locomotor output and synaptic development. Surprisingly, we find that JET and DYSC antagonistically regulate synaptic development at the larval neuromuscular junction, and reduced JET activity rescues arrhythmicity of dysc mutants. Consistent with our prior finding that DYSC regulates SLOWPOKE (SLO) potassium channel expression, jet mutations also rescue circadian and synaptic phenotypes in slo mutants. Collectively, our data suggest that JET, DYSC, and SLO promote circadian output in part by regulating synaptic morphology.

Modeling air quality in the San Joaquin valley of California during the 2013 Discover-AQ field campaign

Abstract The San Joaquin Valley (SJV) of California has one of the nation's most severe wintertime PM2.5 pollution problems. The DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) field campaign took place in the SJV from January 16 to February 6, 2013. It captured two PM2.5 pollution episodes with peak 24-h concentrations approaching 70 μg/m3. Using meteorological fields generated from WRFv3.6, CMAQv5.0.2 was applied to simulate PM2.5 formation in the SJV from January 10 through February 10, 2013. Overall, the model was able to capture the observed accumulation of PM2.5 within the simulation period. The model was able to produce increased concentrations of ammonium nitrate and organic carbon, which are two major components of wintertime PM2.5 in the SJV. Comparison to measurements made by aircraft showed that there was general agreement between observed and modeled daytime vertical distributions of selected gas and particulate species, reflecting the adequacy of modeled daytime mixing layer heights. Excess ammonia predicted by the model implied that ammonium nitrate formation was limited by the availability of nitric acid, consistent with observations. Evaluation of the ammonium nitrate diurnal profile revealed that the observed morning increase of ammonium nitrate was also evident from the model. This paper demonstrates that the CMAQ model is able to simulate elevated wintertime PM2.5 formation observed in the SJV during the DISCOVER-AQ 2013 period, which featured both climatic (i.e., 2011–2014 California Drought) and emissions differences compared to a previous large air quality field campaign in the SJV during 1999–2000.

Diurnal change in psychological and physiological responses to consistent relative humidity.

Diurnal changes in physiological and psychological responses to consistent relative humidity (RH) conditions were investigated in the present study. Lightly clothed six male and six female subjects participated in the first experiment at 40% and 50% RH, and seven male and seven female subjects participated in the second experiment at 60%, 70%, and 80% RH. Both experiments were conducted at 28°C air temperature (Ta) from 9:00-18:30. Skin temperatures, local heat flux rates and tympanic temperature (Tty) were monitored at 2-min intervals throughout the experimental period. Body weight loss and oxygen consumption rate were measured during the 9:30-10:30, 13:30-14:30, and 17:30-18:30 periods. Thermal sensation and thermal comfort responses were recorded at the same periods. The amount of heat loss was greater than metabolic heat production (M) in the male subjects but was well balanced with M in the female subjects. A morning increase in Tty at 50%-80% RH was observed, and mean skin temperature (T‾sk) at 70% and 80% RH was significantly higher (p<0.05) than Tsk at 40% and 50% RH in both subject groups. Although difference in the relationship between thermal sensation and T‾sk based on sex was confirmed, diurnal changes in thermal sensation were observed in both subject groups based on the responses of "warm" in the morning but "neutral" or "slightly warm" in the evening at 70% and 80% RH. This result demonstrates that high RH may be acceptable in the late afternoon and evening at 28°C and indicates that dynamic control of RH during the daytime (e.g., low RH in the morning and high RH in late afternoon) may be beneficial to save energy when using air-conditioning.

Structural and hemodynamic changes in the carotid arteries in young healthy individuals with concentric remodeling of the left ventricle and with normal heart geometry

Remodeling of the heart and blood vessels is a complex multifactorial process that determines the prognosis of a patient with different cardiovascular pathologies. The aim of this work is to study in a comparative aspect the features of the hemodynamics of the carotid arteries as marker vessels of the elastic type and the daily blood pressure profile in young healthy individuals with concentric remodeling of the left ventricle and with normal heart geometry. The study involved practically healthy individuals from 18 to 42, aged 25.3±0.6 years, 56 (73.7%) men and 20 (26.36%) women. All study participants were divided into two equal groups depending on the value of the relative wall thickness of the left ventricle (RTW) for 38 people: for RTW&gt;0.42 (concentric remodeling of the left ventricle) and for RTW≤0.42 (normal geometry of the left ventricle). The following research methods were used: echocardiography, 24-hour blood pressure monitoring, duplex scanning of the neck vessels. Statistical analysis of the study results was calculated using the methods of variational statistics using the StatSoft complex “Statistica” v.12. Although the average daily values of blood pressure and the degree of its nightly decline in both groups did not differ significantly, the speed of the morning rise and the variability of systolic pressure were significantly higher in patients with concentric remodeling than without it. That is, even in the absence of symptoms of cardiovascular disease and a history of a rise in blood pressure, the hemodynamic factor of a fast morning increase in blood pressure can take part in the formation of changes in the geometry of the heart in practically healthy young people. Changes in the speed-time parameters of blood flow in the common carotid arteries in the absence of wall thickening (intima-media complex) and a parallel increase in the lumen of the internal jugular veins found in the study indicate structural and hemodynamic vascular remodeling associated with concentric remodeling of the left ventricle in young, practically healthy persons.

Separate and interacting effects of the endogenous circadian system and behaviors on plasma aldosterone in humans.

Measurements of aldosterone for diagnosis of primary aldosteronism are usually made from blood sampled in the morning when aldosterone typically peaks. We tested the relative contributions and interacting influences of the circadian system, ongoing behaviors, and prior sleep to this morning peak in aldosterone. To determine circadian rhythmicity and separate effects of behaviors on aldosterone, 16 healthy participants completed a 5-day protocol in dim light while all behaviors ranging from sleep to exercise were standardized and scheduled evenly across the 24-h circadian period. In another experiment, to test the separate effects of prior nocturnal sleep or the inactivity that accompanies sleep on aldosterone, 10 healthy participants were studied across 2 nights: 1 with sleep and 1 with maintained wakefulness (randomized order). Plasma aldosterone was measured repeatedly in each experiment. Aldosterone had a significant endogenous rhythm ( P < 0.001), rising across the circadian night and peaking in the morning (~8 AM). Activity, including exercise, increased aldosterone, and different behaviors modulated aldosterone differently across the circadian cycle (circadian phase × behavior interaction; P < 0.001). In the second experiment, prior nocturnal sleep and prior rested wakefulness both increased plasma aldosterone ( P < 0.001) in the morning, to the same extent as the change in circadian phases between evening and morning. The morning increase in aldosterone is due to effects of the circadian system plus increased morning activities and not prior sleep or the inactivity accompanying sleep. These findings have implications for the time of and behaviors preceding measurement of aldosterone, especially under conditions of shift work and jet lag.

A9612 The combination therapy of Xa inhibitor and antihypertensive therapy improved anticoagulant activity and hypertensive target organ damage in nonvalvular atrial fibrillation patients.

Objectives: The anticoagulant activity and blood pressure increase in morning. The aim of this study was to evaluate the change of anticoagulant activity, blood pressure and target organ damage in combination therapy of Xa inhibitor and antihypertensive therapy in nonvalvular atrial fibrillation patients. Methods: We enrolled 72 NVAF patients. Rivaroxaban (10–15 mg) was continuously administered once daily over 8 weeks (study period I). To subjects who have shown early-morning hypertension in the study period I (N = 50), nifedipine was additionally administered at bedtime, and the rivaroxaban administration was continued for additional 8 weeks. We assessed prothrombin fragment 1 + 2, optimal range of prothrombin fragment 1 + 2 was defined 69–229pmol/L, D-Dimer, positive D-dimer measurement (≥1.0 μg/mL), and evaluated urinary albumin creatinine ratio (UACR) as hypertensive target organ damage. Results: The percentage of optimal range of prothrombin fragment 1 + 2 was significantly increased from baseline at 4 weeks (70.8 vs. 86.1%, p = 0.033). Clinic systolic blood pressure was reduced at 12 weeks (134.7 ± 9.6 vs. 118.7 ± 9.6mmHg, p < 0.003) and 16weeks (134.7 ± 9.6 vs. 118.7 ± 9.6mmHg, p < 0.003)). UACR was significantly reduced from 8 weeks at 12 weeks (median UACR: 13.7 vs. 8.8 mg/gCR, p = 0.006). The percentage of positive D-dimer reduced from baseline to 8 weeks (8% vs. 0%, p = 0.044), and remained 0% at 16 weeks. Conclusion: The combination therapy of Xa inhibitor and antihypertensive therapy improved anticoagulant activity and hypertensive target organ damage in nonvalvular atrial fibrillation patients.