Caloric Data Research Articles

Machine learning models help differentiate between causes of recurrent spontaneous vertigo.

Vestibular migraine (VM) and Menière's disease (MD) are two common causes of recurrent spontaneous vertigo. Using history, video-nystagmography and audiovestibular tests, we developed machine learning models to separate these two disorders. We recruited patients with VM or MD from a neurology outpatient facility. One hundred features from six "feature subsets": history, acute video-nystagmography and four laboratory tests (video head impulse test, vestibular-evoked myogenic potentials, caloric testing and audiogram) were used. We applied ten machine learning algorithms to develop classification models. Modelling was performed using three "tiers" of data availability to simulate three clinical settings. "Tier 1" used all available data to simulate the neuro-otology clinic, "Tier 2" used only history, audiogram and caloric test data, representing the general neurology clinic, and "Tier 3" used history alone as occurs in primary care. Model performance was evaluated using tenfold cross-validation. Data from 160 patients with VM and 114 with MD were used for model development. All models effectively separated the two disorders for all three tiers, with accuracies of 85.77-97.81%. The best performing algorithms (AdaBoost and Random Forest) yielded accuracies of 97.81% (95% CI 95.24-99.60), 94.53% (91.09-99.52%) and 92.34% (92.28-96.76%) for tiers 1, 2 and 3. The best feature subset combination was history, acute video-nystagmography, video head impulse test and caloric testing, and the best single feature subset was history. Machine learning models can accurately differentiate between VM and MD and are promising tools to assist diagnosis by medical practitioners with diverse levels of expertise and resources.

Thermodynamics of Reversible Hydrogen Storage: Are Methoxy‐Substituted Aromatics better through Oxygen Functionality?

AbstractAn attractive option for the storage of hydrogen is the reversible hydrogenation of an aromatic substance, a so‐called liquid organic hydrogen carrier. For hydrogen release, it is desirable to find substances with low enthalpies of reaction for dehydrogenation. It has been demonstrated that substitution, e.g., with methyl groups, on the ring can have a positive effect in this regard. In this study, thermochemical properties of methoxy‐substituted pyridines and quinolines and their respective hydrogenated counterparts have been analyzed from a thermodynamic point of view. Combustion calorimetry has been utilized to measure the enthalpy of formation and the transpiration method for determining the vapor pressure. Additionally, high‐level quantum‐chemical approaches have been applied to obtain caloric data in the gas phase, which provide a basis for comparison and evaluation of the experimental data. The results reveal two main effects of methoxy substitution. First, oxygenated substituents like methoxy groups have stronger effect on the Gibbs energy of reaction and thus the temperature needed thermodynamically for hydrogen release than methyl groups. Second, the effect is highly depending on the position of the substitution on the ring. Particularly methoxy groups close to a N heteroatom can have a significant positive effect, which might enable hydrogen release at equilibrium temperatures more than 50 K lower than for their unsubstituted analogue.

Triple semicircular canal occlusion with endolymphatic sac decompression for intractable Meniere's disease.

Meniere's disease (MD) is characterized by idiopathic endolymphatic hydrops (ELH). Frequent vertigo attacks is the most disabling symptom of MD. This study evaluated the efficacy of triple semicircular canal occlusion combined with endolymphatic sac decompression in the treatment of frequent vertigo in patients with MD. Eleven patients with complete medical records were included in this study conducted from May 2021 to April 2022. All patients were enrolled to undergo triple semicircular canal occlusion (TSCO) with endolymphatic sac decompression (ESD). Various tests including pure tone audiometry (PTA), vestibular evoked myogenic potentials (VEMPs), the video head impulse test (v-HIT), caloric test data, the Dizziness Handicap Inventory (DHI), the Berg Balance Scale (BBS), and the Tinnitus Handicap Inventory (THI) were performed both before and after the surgery. The successful control rate of vertigo was 100% (9/9) in the average 23-month postoperative follow-up period, with complete control rate of 88.89% (8/9) and substantial control rate of 11.11% (1/9). Triple semicircular canal occlusion combined with ESD may be an effective treatment option for managing frequent vertigo attacks in patients with MD. This combination therapy has the potential to become a significant addition to the treatment framework for MD.

Subjective and objective responses to caloric stimulation help separate vestibular migraine from other vestibular disorders

BackgroundNystagmus generated during bithermal caloric test assesses the horizontal vestibulo-ocular-reflex. Any induced symptoms are considered unwanted side effects rather than diagnostic information.AimWe hypothesized that nystagmus slow-phase-velocity (SPV) and subjective symptoms during caloric testing would be higher in vestibular migraine (VM) patients compared with peripheral disorders such as Meniere’s disease (MD) and non-vestibular dizziness (NVD).MethodsConsecutive patients (n = 1373, 60% female) referred for caloric testing were recruited. During caloric irrigations, patients scored their subjective sensations. We assessed objective-measures, subjective vertigo (SVS), subjective nausea (SNS), and test completion status.ResultsNystagmus SPV for VM, MD (unaffected side), and NVD were 29 ± 12.8, 30 ± 15.4, and 28 ± 14.2 for warm irrigation and 24 ± 8.9, 22 ± 10.0, and 25 ± 12.8 for cold-irrigation. The mean SVS were 2.5 ± 1.1, 1.5 ± 1.33, and 1.5 ± 1.42 for warm irrigation and 2.2 ± 1.1, 1.1 ± 1.19, and 1.1 ± 1.16 for cold-irrigation. Age was significantly correlated with SVS and SNS, (p < 0.001) for both. The SVS and SNS were significantly higher in VM compared with non-VM groups (p < 0.001), and there was no difference in nystagmus SPV. VM patients SVS was significantly different to the SVS of migraineurs in the other diagnostic groups (p < 0.001). Testing was incomplete for 34.4% of VM and 3.2% of MD patients. To separate VM from MD, we computed a composite value representing the caloric data, with 83% sensitivity and 71% specificity. Application of machine learning to these metrics plus patient demographics yielded better separation (96% sensitivity and 85% specificity).ConclusionPerceptual differences between VM and non-VM patients during caloric stimulation indicate that subjective ratings during caloric testing are meaningful measures. Combining objective and subjective measures could provide optimal separation of VM from MD.

New Thermodynamic Equation of State for Refrigerant HFO-1243zf

R-1243zf is a new refrigerant that could replace R-134a. Its thermodynamic properties represented in the equation of state (EOS) play an essential role in analyzing and designing thermal systems. The EOS exists without including caloric property data due to unavailable data during the development time. New EOS was developed explicitly in Helmholtz free energy and optimized to represent the experimental data accurately and maintain thermodynamic consistency. The optimization process undergoes using a genetic algorithm and weighted-least squares regression. The experimental data used in the optimization have a range of 233–430 K and 0.106–34.6 MPa and were validated from the extrapolation and consistency to confirm the reliability. The average absolute deviation from the data is 0.48% for the ideal gas isobaric specific heat, 1.7% for the isochoric specific heat, 0.33% for the speed of sound, 0.22% for the liquid density in single-phase, 0.49% for the vapor density in single-phase, 0.96% for the vapor pressure, 2.2% for the saturated liquid density, and 3.2% for the saturated vapor density. The EOS has a reasonable extrapolation behavior from the triple point up to 700 K and 100 MPa.

Abstract P521: Association Between Dietary Phytosterols and Risk of Cardiovascular Disease Mortality in US Adults: Findings From the Third National Health and Nutrition Examination Survey (NHANES III), 1988-1994

Introduction: Phytosterols (plant sterols) are naturally occurring components of plant food sources, including vegetable oils, nuts, cereals and legumes. Their chemical structure impedes intestinal cholesterol absorption and regular consumption has been related to lower serum low-density cholesterol (LDL-C), a causal risk factor for cardiovascular disease (CVD). The association between dietary plant sterol intake and CVD has yet to be determined. Objective: We aimed to examine the association of phytosterol consumption in the diet with cardiovascular mortality in US adults the National Health &amp; Nutrition Examination Survey III (NHANES III), 1988-1994. Methods: We conducted a prospective cohort analysis on National Health and Nutrition Examination Survey (NHANES, 1988-1994 [III]), linked with the National Death Index mortality data (2015) to associate dietary phytosterol intake from 24h dietary recall data with CVD mortality. We included 13,004 adults aged ≥20 years who were non-pregnant, free of CVD at baseline and completed ≥1 24h dietary recall with plausible caloric intake data. We excluded individuals with death occurring within 1 year of baseline. We created a database quantifying the phytosterol content of foods in the 24h dietary recall data and estimated usual intake by quintiles using the NCI method. We determined the risk function by regression calibration and estimated CVD mortality risk between the 10 th (Q1) and 90 th (Q5) percentiles of usual intake. Data was adjusted for sex, age, smoking status and ethnicity. Results: Over a mean±SD follow-up period of 21.2±5.1y, 949 CVD deaths occurred in a population with a mean±SD age of 44.2±14.3y, BMI 26.7±4.7 kg/m 2 and mean dietary plant sterol usual intake of 272.3 mg/day. The top sources of dietary phytosterols were from potatoes 23%), wheat and other grains (21%) and beans, legumes and nuts (13%). Mean usual intake plant intake in the 10 th (Q1) and 90 th (Q5) percentiles of the population was 150.1 and 414.0 mg/day. The estimated relative risk for CVD mortality between Q1 (ref) and Q5 was 0.972 (p&lt;0.05). Conclusions: Preliminary analyses suggest a CVD death risk reduction of 2.8% in the highest versus lowest intakes of dietary plant sterols in the US population. We plan to expand the multivariable model to include the Healthy Eating Index (diet quality) and assess stratification by healthful and unhealthful sources of phytosterols and linear and non-linear dose response analyses to determine the robustness of the association. OSF Registration: osf.io/da4sg Funding: Amgen Scholars Program, Canadian Institutes of Health Research (CIHR), Banting and Best Diabetes Centre (BBDC), Toronto 3D Knowledge Synthesis and Clinical Trials foundation

Ms2: A molecular simulation tool for thermodynamic properties, release 4.0

A new version release (4.0) of the molecular simulation tool ms2 (Deublein et al. 2011; Glass et al. 2014; Rutkai et al. 2017) is presented. Version 4.0 of ms2 features two additional potential functions to address the repulsive and dispersive interactions in a more versatile way, i.e. the Mie potential and the Tang–Toennies potential. This version further introduces Kirkwood–Buff integrals based on radial distribution functions, which allow the sampling of the thermodynamic factor of mixtures with up to four components, orientational distribution functions to elucidate mutual configurations of neighboring molecules, thermal diffusion coefficients of binary mixtures for heat, mass as well as coupled heat and mass transport, Einstein relations to sample transport properties with an alternative to the Green–Kubo formalism, dielectric constant of non-polarizable fluid models, vapor–liquid equilibria relying on the second virial coefficient and cluster criteria to identify nucleation. New version programm summaryProgram Title: ms2Program Files doi:http://dx.doi.org/10.17632/nsfj67wydx.3Licensing provisions: CC by NC 3.0Programming language: Fortran95Supplemental material: A detailed description of the parameter setup for the introduced methods, properties, functionalities etc. is given in the supplemental material. Furthermore, all molecular force field models developed by our group are provided by the MolMod Database: Stephan et al., Mol. Sim. 45 (2019) 806Journal reference of previous version: Deublein et al., Comput. Phys. Commun. 182 (2011) 2350 and Glass et al., Comput. Phys. Commun. 185 (2014) 3302 and Rutkai et al., Comput. Phys. Commun. 221 (2017) 343Does the new version supersede the previous version?: YesReasons for the new version: Introduction of new features as well as enhancement of computational efficiencySummary of revisions: Two new potential functions to address repulsive and dispersive interactions (Mie and Tang–Toennies potential), new properties (Helmholtz energy, Kirkwood–Buff integrals, thermodynamic factor, thermal diffusion coefficients, dielectric constant, mean squared displacement and non-Gaussian parameter), new functionalities (Kirkwood–Buff integration with extrapolation to the thermodynamic limit, van der Vegt correction for the radial distribution function, orientational distribution function, Einstein relations, vapor–liquid equilibria estimations, cluster criteria to identify nucleation).Nature of problem: Calculation of application-oriented thermodynamic properties: vapor–liquid equilibria of pure fluids and multi-component mixtures, thermal, caloric and entropic data as well as transport properties and data on microscopic structureSolution method: Molecular dynamics, Monte Carlo, various ensembles, Grand equilibrium method, Green–Kubo formalism, Einstein formalism, Lustig formalism, OPAS method, smooth-particle mesh Ewald summation.

The Baseline Gut Microbiota Directs Dieting-Induced Weight Loss Trajectories

Elucidating key factors affecting personal responses to food is the first step toward implementing personalized nutrition strategies in for example weight loss programs. Here, we aimed to identify factors of importance for individual weight loss trajectories in a natural setting where participants were provided dietary advice but otherwise asked to self-manage the daily caloric intake and data reporting. A 6-month weight-reduction program with longitudinal collection of dietary, physical activity, body weight, and fecal microbiome data as well as single-nucleotide polymorphism genotypes in 83 participants was conducted, followed by integration of the high-dimensional data to define the most determining factors for weight loss in a dietician-guided, smartphone-assisted dieting program. The baseline gut microbiota was found to outperform other factors as a predieting predictor of individual weight loss trajectories. Weight loss was also linked to the magnitude of changes in abundances of certain bacterial species during dieting. Ruminococcus gnavus (MGS0160) was significantly enriched in obese individuals and decreased during weight loss. Akkermansia muciniphila (MGS0120) and Alistipes obesi (MGS0342) were significantly enriched in lean individuals, and their abundance increased during dieting. Finally, Blautia wexlerae (MGS0575) and Bacteroides dorei (MGS0187) were the strongest predictors for weight loss when present in high abundance at baseline. Altogether, the baseline gut microbiota was found to excel as a central personal factor in capturing the relationship between dietary factors and weight loss among individuals on a dieting program.

Equation of liquid, gas, and fluid state for methane

Using methods and approaches, previously developed by the authors, a new fundamental low-parametric equation of state for methane (in the form of the reduced Helmholtz function) has obtained to describe the thermodynamic properties. It allows describing the thermal properties of gas, liquid, and fluid at pressures of up to 20 MPa with sufficiently high accuracy close to the experimental one (with the exception of the critical region). The sound speed and caloric properties of methane have been calculated without involving any caloric data, with the exception of ideal gas enthalpy. The values of speed of sound, isochoric heat capacity, and other thermodynamic properties obtained by calculations are in good agreement with the experimental data.

The APOB rs693 polymorphism impacts the lipid profile of Brazilian older adults.

The apolipoprotein B (APOB) gene contains several polymorphic sites described as risk modifiers for cardiovascular events. The objective of this study was to verify the association of the classic APOB Xba I polymorphism (rs693) with atherosclerotic risk factors in a segment of the Brazilian elderly population considering their usual dietary intake. Clinical and biochemical characteristics as well as total caloric and fat intake data were determined from 644 elderly individuals. Polymorphism analysis was performed by conventional polymerase chain reaction followed by enzyme restriction. Statistical analyses compared measures and proportions according to different APOB genotypic combinations. Statistically significant association was found between Xba I polymorphism and serum LDL, total cholesterol, and total lipid levels, with important elevations among T homozygotes compared to the other genotypes. There was homogeneity in all other parameters analyzed (including intake pattern), with a tendency for reduced levels of circulating apolipoprotein B among TT individuals. Our results pointed out that genetic variation in APOB affected the lipemic profile of elderly individuals in a context not biased by diet, generating a pattern suggestive of secretory disorder of lipoprotein particles, with possible implication in atherosclerotic risk.

Calculating the Thermodynamic Properties of Carbon Dioxide in the Range of Pressures up to 200 MPa

A new fundamental low-parametric equation of state in the form of a reduced Helmholtz function is developed for carbon dioxide to describe the thermodynamic properties of normal substances. The equation of state makes it possible to describe the thermal and caloric properties of a gas, liquid, or supercritical fluid in the range of pressures up to 200 MPa with high accuracy that is close to experimental (except in the critical region). Carbon dioxide’s caloric properties and speed of sound in it are calculated without using any caloric data, except for the ideal gas enthalpy. The calculated values of the isochoric heat capacity, speed of sound, and other thermodynamic properties are in good agreement with experimental data (reliable reference tables).

The risk of refeeding syndrome among severely malnourished tuberculosis patients in Chhattisgarh, India

BackgroundA secondary care hospital in rural India serving a highly tuberculosis (TB) and malnutrition endemic region. ObjectiveIn this study conducted on patients with chronic protein energy malnutrition (PEM) and TB, we sought to compare nurse-estimated vs. smartphone photograph analytic methods for assessing caloric intake and determine the incidence of refeeding hypophosphatemia (RH) and refeeding syndrome (RFS) in patients with TB. MethodsInpatients were prospectively enrolled. Baseline demographic, comorbidity and preadmission caloric data were collected. Nurse estimated caloric intake was compared with digital “before and after” meal images. Serum phosphorus was measured on days 1, 3 and 7 post admission. Patients with RH underwent further evaluation for RFS-associated findings. Results27 patients were enrolled. 85% were at risk of RFS by National Institute for Health and Care Excellence (NICE) criteria. Significant discrepancy (>700 calories) was noted between nurse-estimated caloric intake compared to digital images. RH was found in 37% (10/27). None developed clinical RFS. ConclusionsOur study suggests more standardized methods of caloric intake are needed in resource-limited settings with high co-prevalence of PEM and TB. We noted that despite RH being common in inpatients with PEM+TB given high caloric diets, RFS was not detected.

The simple fundamental equation of state for liquid, gas, and fluid of xenon

To describe the thermodynamic properties of xenon, a new fundamental low-parametric equation of state (in the form of reduced Helmholtz energy) is obtained with the help of the methods and approaches developed by the authors. It allows us to describe the thermal properties of gas, liquid, and fluid with a sufficiently high accuracy close to the accuracy of experiment in a range from the density in the ideal gas state to the density at the triple point, excluding the critical region. The caloric properties and speed of xenon sound are calculated without involving any caloric data, with the exception of ideal gas enthalpy. The values of isobaric heat capacity, sound speed, and other thermodynamic properties obtained by calculations are in good agreement with the experimental data.

Comparison of Caloric Expenditure in a Smart Watch and Portable Metabolic Cart

PURPOSE: To validate a Smart Watch (SW) for wheelchair users by comparing caloric energy expenditure (EE) against expired gas analysis. Valid activity tracking will be helpful for clinicians, patients and consumers and may help increase physical activity levels among wheelchair users. METHODS: Five wheelchair users (age=50.0(5.6)) and three able-bodied (age=25.3(3.2)) participants completed a series of exercises including wheelchair treadmill propulsion at 30, 45, and 60 strokes per minute (spm) and arm cycle ergometry at 45, 60, and 80rpm. They were equipped with a SW on their dominant hand, heart rate monitor, and a portable metabolic tracking cart. The bundled workout app was used for each task. Caloric expenditure data was extracted from both devices and compared by Bland-Altman analysis. RESULTS: For treadmill tasks, the SW reported the average EE at 30, 45, and 60spm frequencies were 7(2.0), 8(2.3) and 9(2.0) kcals, respectively. At the same frequencies, the metabolic cart expenditures read 10(3.9), 12(5.3), and 15(6.7). Bland-Altman analysis showed relatively poor agreement between the cart and watch at 30spm (mean difference 3 with limits of agreement (LoA) -4–9). Mean absolute percent error (MAPE) was 21.56%. Agreement worsened at higher stroke frequencies, 45spm (4(- 4–12)) and 60spm (6(-4–10)). MAPE was 29.11% and 35.88%, respectively. For arm ergometry, the average EE reported by the watch at 45, 60, and 80rpm were 7(1.0), 9(1.5), and 11(1.4). Metabolic cart expenditures were 6(3.0), 7(2.4), and 8(2.8) at the same frequencies. Bland-Altman analysis showed good agreement at 45rpm (-0.4(-6–5)) with a MAPE of 32.69%. Agreement worsened at higher frequencies, 60rpm (-3(-6–1)) and 80rpm (-2(-7–2)). MAPE was 58.57% and 48.54%, respectively. CONCLUSION: While performing a treadmill task, the SW underestimated caloric expenditure, but overestimated for arm ergometry. The activity tracker records EE with good validity only at lower frequency tasks.

Energy Intake Derived from an Energy Balance Equation, Validated Activity Monitors, and Dual X-Ray Absorptiometry Can Provide Acceptable Caloric Intake Data among Young Adults

Assessments of energy intake (EI) are frequently affected by measurement error. Recently, a simple equation was developed and validated to estimate EI on the basis of the energy balance equation [EI = changed body energy stores + energy expenditure (EE)]. The purpose of this study was to compare multiple estimates of EI, including 2 calculated from the energy balance equation by using doubly labeled water (DLW) or activity monitors, in free-living adults. The body composition of participants (n = 195; mean age: 27.9 y; 46% women) was measured at the beginning and end of a 2-wk assessment period with the use of dual-energy X-ray absorptiometry. Resting metabolic rate (RMR) was calculated through indirect calorimetry. EE was assessed with the use of the DLW technique and an arm-based activity monitor [Sensewear Mini Armband (SWA); BodyMedia, Inc.]. Self-reported EI was calculated by using dietitian-administered 24-h dietary recalls. Two estimates of EI were calculated with the use of a validated equation: quantity of energy stores estimated from the changes in fat mass and fat-free mass occurring over the assessment period plus EE from either DLW or the SWA. To compare estimates of EI, reporting bias (estimated EI/EE from DLW × 100) and Goldberg ratios (estimated EI/RMR) were calculated. Mean ± SD EEs from DLW and SWA were 2731 ± 494 and 2729 ± 559 kcal/d, respectively. Self-reported EI was 2113 ± 638 kcal/d, EI derived from DLW was 2723 ± 469 kcal/d, and EI derived from the SWA was 2720 ± 730 kcal/d. Reporting biases for self-reported EI, DLW-derived EI, and SWA-derived EI are as follows: -21.5% ± 22.2%, -0.7% ± 18.5%, and 0.2% ± 20.8%, respectively. Goldberg cutoffs for self-reported EI, DLW EI, and SWA EI are as follows: 1.39 ± 0.39, 1.77 ± 0.38, and 1.77 ± 0.38 kcal/d, respectively. These results indicate that estimates of EI based on the energy balance equation can provide reasonable estimates of group mean EI in young adults. The findings suggest that, when EE derived from DLW is not feasible, an activity monitor that provides a valid estimate of EE can be substituted for EE from DLW.

The peculiar features of vestibular function disorders associated with Meniere's disease

The objective of the present study was to reveal the special aspects of vestibular dysfunction in the patients presenting with unilateral Meniere's disease (MD) during the attack-free intervals. The study included 23 patients suffering from unilateral MD; all of them were examined with the use of tonal threshold audiometry, videonystagmography, the caloric test and video head-impulse test (vHIT). The study has demonstrated that the patients with MD are characterized, during the attack-free intervals, by the absence of latent spontaneous nystagmus in conjunction with the positive results of the head shaking test. Moreover, asymmetry of the results of the caloric test together with the normal results of the video head-impulse test is shown to be the characteristic feature of the patients with unilateral MD. The analysis of the degree of sensorineural hearing loss, the caloric test data, and coefficient of labyrinth asymmetry (CLAS) gave evidence of the tendency toward the elevation of the hearing threshold with increasing CLAS.

Formula omitted]: A molecular simulation tool for thermodynamic properties, release 3.0

A new version release (3.0) of the molecular simulation tool ms 2 (Deublein et al., 2011; Glass et al. 2014) is presented. Version 3.0 of ms 2 features two additional ensembles, i.e. microcanonical (NVE) and isobaric–isoenthalpic (NpH), various Helmholtz energy derivatives in the NVE ensemble, thermodynamic integration as a method for calculating the chemical potential, the osmotic pressure for calculating the activity of solvents, the six Maxwell–Stefan diffusion coefficients of quaternary mixtures, statistics for sampling hydrogen bonds, smooth-particle mesh Ewald summation as well as the ability to carry out molecular dynamics runs for an arbitrary number of state points in a single program execution. New version program summaryProgram Title:ms2Program Files doi:http://dx.doi.org/10.17632/9rcrykvkyh.1Licensing provisions: CC by NC 3.0Programming language: Fortran95Supplementary material: A detailed description of the parameter setup for thermodynamic integration and hydrogen bonding is given in the supplementary material. Furthermore, all molecular force field models developed by our group are providedJournal reference of previous versions: Deublein et al., Comput. Phys. Commun. 182 (2011) 2350 and Glass et al., Comput. Phys. Commun. 185 (2014) 3302Does the new version supersede the previous version?: YesReasons for the new version: Introduction of new features as well as enhancement of computational efficiencySummary of revisions: Two new ensembles (NVE and NpH), new properties (Helmholtz energy derivatives, chemical potential via thermodynamic integration, activity coefficients via osmotic pressure, Maxwell–Stefan diffusion coefficients of quaternary mixtures), new functionalities (detection and statistics of hydrogen bonding, smooth-particle mesh Ewald summation, ability to carry out molecular dynamics runs for an arbitrary number of state points in a single program execution).Nature of problem: Calculation of application oriented thermodynamic properties: vapor–liquid equilibria of pure fluids and multi-component mixtures, thermal, caloric and entropic data as well as transport properties and data on microscopic structureSolution method: Molecular dynamics, Monte Carlo, various ensembles, Grand Equilibrium method, Green–Kubo formalism, Lustig formalism, OPAS method, smooth-particle mesh Ewald summationRestrictions: Typical problems addressed by ms2 are solved by simulating systems containing 1000 to 5000 molecules that are modeled as rigid bodies.Additional comments: Documentation is available at http://www.ms-2.de

Simple fundamental equation of state for liquid, gas, and fluid of argon, nitrogen, and carbon dioxide

A new fundamental low-parametric equation of state in the form of reduced Helmholtz function for describing thermodynamic properties of normal substances was obtained using the methods and approaches developed earlier by the authors. It allows us to describe the thermal properties of gas, liquid, and fluid in the range from the density in ideal-gas state to the density at a triple point (except the critical region) with sufficiently high accuracy close to the accuracy of experiment. The caloric properties and sound velocity of argon, nitrogen, and carbon dioxide are calculated without involving any caloric data, except the ideal gas enthalpy. The obtained values of isochoric heat capacity, sound velocity, and other thermodynamic properties are in good agreement with experimental (reliable tabular) data.

Impairment of Caloric Function After Cochlear Implantation.

This article seeks to review current literature on caloric function following cochlear implantation while analyzing any correlations of caloric function changes with vestibular symptoms. This article is a systematic review of evidence-based literature. English language articles published between 1980 and 2014 that presented some form of caloric data from cochlear implant (CI) patients and that did not solely analyze overlapping data from a previous study were reviewed. Twenty-five articles met these criteria. Of the 439 individuals tested, 37% of patients demonstrated reduced maximum slow-phase velocity, and 34% had onset of caloric asymmetry post-CI. This review article found that cochlear implantation can affect caloric responses but is variable. When counseling patients preoperatively, possible effects of CI on labyrinthine function should be discussed.

Absorption of SO2 in different electrolyte solutions, seawater and brine

A systematic study of the SO2 solubility of binary systems (SO2+water+1 electrolyte) and of the complex mixtures seawater and brine was performed. The experimental setup allowed a comprehensive description of the equilibrium state by a UV spectroscopic measurement of the partial pressure of SO2 in the gas phase and the concentration of sulfur compounds in the liquid phase. The influence of main ions present in the brine (e.g., Na+, Cl−, K+, Mg2+, Ca2+, HCO3−) was studied at 298 and 323K. The experiments revealed considerable deviations of already existing models from experimental data mainly at higher temperatures. A thermodynamic model based on caloric data and a Pitzer and a Sechenov approach for the calculation of activity coefficients was fitted to experimental data. This work demonstrates that fitting selected Pitzer parameters improves the model performance very much. The new model provides a reliable prediction of SO2 solubility over the entire investigated range of temperature and concentrations.