Ion-water clusters, bulk medium effects, and ion hydration

Thermochemistry of gas-phase ion-water clusters together with estimates of the hydration free energy of the clusters and the water ligands are used to calculate the hydration free energy of the ion. Often the hydration calculations use a continuum model of the solvent. The primitive quasichemical approximation to the quasichemical theory provides a transparent framework to anchor such efforts. Here we evaluate the approximations inherent in the primitive quasichemical approach and elucidate the different roles of the bulk medium. We find that the bulk medium can stabilize configurations of the cluster that are usually not observed in the gas phase, while also simultaneously lowering the excess chemical potential of the ion. This effect is more pronounced for soft ions. Since the coordination number that minimizes the excess chemical potential of the ion is identified as the optimal or most probable coordination number, for such soft ions, the optimum cluster size and the hydration thermodynamics obtained without account of the bulk medium on the ion-water clustering reaction can be different from those observed in simulations of the aqueous ion. The ideas presented in this work are expected to be relevant to experimental studies that translate thermochemistry of ion-water clusters to the thermodynamics of the hydrated ion and to evolving theoretical approaches that combine high-level calculations on clusters with coarse-grained models of the medium

Snowmelt hydrology in the upper Kuparuk watershed, Alaska: observations and modeling

Thesis (M.S.) University of Alaska Fairbanks, 2019The Fourth National Climate Assessment Report (2018) indicates that Alaska has been warming at a rate two times greater than the global average with the Arctic continuing to be experiencing higher rates of warming. Snowmelt driven runoff is the largest hydrologic event of the year in many Alaska Arctic river systems. Changes to air temperature, permafrost, and snow cover impact the timing and magnitude of snowmelt runoff. This thesis examines the variability in hydrometeorological variables associated with snowmelt to better understand the timing and magnitude of snowmelt runoff in headwater streams of Arctic Alaska. The objectives of this thesis are to: (1) use observational data to evaluate trends in air temperature, precipitation, snow accumulation, and snowmelt runoff data; (2) relate precipitation, snow cover, and air temperature to snowmelt runoff using the physically-based Snowmelt Runoff Model (SRM) to test the applicability of the model for headwater streams in the Arctic. The focus of this study is the Upper Kuparuk watershed area, located in Alaska on the north side of the Brooks Range, where several monitoring programs have operated long enough to generate a 20-year climate record, 1993-2017. Long-term air temperature, precipitation, and streamflow data collected by the University of Alaska Fairbanks at the Water and Environmental Research Center and other agencies were used for statistical analysis and modeling. While no statistically significant trends in snow accumulation and snowmelt runoff were identified during 1993-2017, observations highlight large year-to-year variability and include extreme years. Snow water equivalent ranges from 5.4 to 17.6 cm (average 11.0 cm), peak snowmelt runoff ranges from 3.84 to 50.0 cms (average 22.4 cms), and snowmelt peak occurrence date ranges from May 13 to June 5 for the Upper Kuparuk period of record. The spring of 2015 stands out as the warmest, snowiest year on record in the Upper Kuparuk. To further investigate the runoff response to snowmelt in 2015, remote sensing snow data was analyzed and recommended parameters were developed for SRM use in the Upper Kuparuk watershed. Recommended parameters were then applied to 2013 snowmelt runoff as a test year. Model results varied between the two years and provide good first-order approximation of snowmelt runoff for headwater rivers in the Alaska Arctic.National Institute of Water Resource

Automated Ecological Assessment of Physical Activity: Advancing Direct Observation.

Technological advances provide opportunities for automating direct observations of physical activity, which allow for continuous monitoring and feedback. This pilot study evaluated the initial validity of computer vision algorithms for ecological assessment of physical activity. The sample comprised 6630 seconds per camera (three cameras in total) of video capturing up to nine participants engaged in sitting, standing, walking, and jogging in an open outdoor space while wearing accelerometers. Computer vision algorithms were developed to assess the number and proportion of people in sedentary, light, moderate, and vigorous activity, and group-based metabolic equivalents of tasks (MET)-minutes. Means and standard deviations (SD) of bias/difference values, and intraclass correlation coefficients (ICC) assessed the criterion validity compared to accelerometry separately for each camera. The number and proportion of participants sedentary and in moderate-to-vigorous physical activity (MVPA) had small biases (within 20% of the criterion mean) and the ICCs were excellent (0.82-0.98). Total MET-minutes were slightly underestimated by 9.3-17.1% and the ICCs were good (0.68-0.79). The standard deviations of the bias estimates were moderate-to-large relative to the means. The computer vision algorithms appeared to have acceptable sample-level validity (i.e., across a sample of time intervals) and are promising for automated ecological assessment of activity in open outdoor settings, but further development and testing is needed before such tools can be used in a diverse range of settings

The Prevalence of Pulmonary and Upper Respiratory Tract Symptoms and Spirometric Test Findings Among Newspaper Pressroom Workers Exposed to Solvents

To investigate the relationship between exposure to organic solvents and the presence of pulmonary and upper respiratory tract mucous membrane symptoms, we conducted a cross-sectional study of 215 newspaper pressroom workers who were occupationally exposed to organic solvent and lubricant mixtures. Thirty-four compositors, who were not occupationally exposed to the solvents or lubricants, served as controls. Pressroom workers and compositors underwent spirometric testing and were also asked about the presence of cough, phlegm, hemoptysis, dyspnea, wheezing, chest tightness, nose or throat irritation, eye irritation, and sinus trouble. The spirometric results did not significantly differ between the two groups. However, the pressroom workers were significantly more likely to report pulmonary or upper respiratory tract mucous membrane symptoms than were compositors (P \u3c 0.005). An exposure-response relationship could be demonstrated when comparing the number of solvents exposed with the total number of symptoms (P \u3c 0.001). Similarly, an exposure-response relationship could be demonstrated when comparing the frequency of use of each of the seven solvents with the total number of symptoms (P \u3c 0.002). Each of these findings was supported in a multivariable linear regression model that adjusted for potential confounders such as age, smoking history, and number of years in the industry. A high prevalence of these symptoms was reported even though the degree of exposure to solvents and lubricants was within the current permissible exposure limits

A Randomized Controlled Trial of an Outpatient Protocol for Transitioning Children from Tube to Oral Feeding: No Need for Amitriptyline.

ObjectiveTo assess the role of amitriptyline in the effectiveness of an outpatient protocol for weaning medically complicated children from tube to oral feeding.Study designTwenty-one children seen in multidisciplinary outpatient feeding teams across 4 sites were recruited to a randomized placebo-controlled trial of a 6-month outpatient treatment protocol with behavioral, oral-motor, nutrition, and medication components.ResultsAll of the children who completed the 6-month program (73%) were weaned to receive only oral feeding, regardless of group assignment. The transition from tube to oral feeding resulted in decreases in body mass index percentile and pain, some improvements in quality of life, and no statistically significant changes in cost.ConclusionsAmitriptyline is not a key component of this otherwise effective outpatient, interdisciplinary protocol for weaning children from tube to oral feeding.Trial registrationClinicalTrials.gov: NCT01206478

iKanEat: Protocol for a randomized controlled trial of megestrol as a component of a pediatric tube weaning protocol

Background Although tube feeding routinely saves the lives of children who do not eat by mouth, chronic tube feeding can be a burden to patients, caregivers, and families. Very few randomized trials exist regarding the best methods for weaning children from their feeding tubes. Methods The current paper describes a randomized controlled trial of an empirically supported outpatient treatment protocol for moving children from tube to oral eating called iKanEat. Specifically, we describe the methods of randomized double-blind, placebo-controlled trial which includes a 4-week course of megestrol, the only medication used in the iKanEat protocol, to determine whether the addition of megestrol results in improved child outcomes. The primary and secondary aims are to assess the safety and efficacy of megestrol as part of the iKanEat protocol. The third aim is to provide critical information about the impact of the transition from tube to oral feeding on parent stress and parent and child quality of life. Discussion This trial will provide data regarding whether megestrol is a safe and effective component of the iKanEat tube weaning protocol, as well as important data on how the tube weaning process impacts parent stress and parent and child quality of life

Recruitment and reach in a school-based pediatric obesity intervention trial in rural areas

Introduction: The purpose of this study is to evaluate two recruitment strategies on schools and participant participation rates and representativeness (reach) within a pediatric obesity treatment trial tailored for families who live in rural areas. Methods: Recruitment of schools was evaluated based on their progress toward enrolling participants. Recruitment and reach of participants were evaluated using (1) participation rates and (2) representativeness of demographics and weight status of participants compared to eligible participants (who did not consent and enroll) and all students (regardless of eligibility). School recruitment, as well as participant recruitment and reach, were evaluated across recruitment methods comparing opt-in (i.e., caregivers agreed to allow their child to be screened for eligibility) vs. screen-first (i.e., all children screened for eligibility). Results: Of the 395 schools contacted, 34 schools (8.6%) expressed initial interest; of these, 27 (79%) proceeded to recruit participants, and 18 (53%) ultimately participated in the program. Of schools who initiated recruitment, 75% of schools using the opt-in method and 60% of schools using the screen-first method continued participation and were able to recruit a sufficient number of participants. The average participation rate (number of enrolled individuals divided by those who were eligible) from all 18 schools was 21.6%. This percentage was higher in schools using the screen-first method (average of 29.7%) compared to schools using the opt-in method (13.5%). Study participants were representative of the student population based on sex (female), race (White), and eligibility for free and reduced-price lunch. Study participants had higher body mass index (BMI) metrics (BMI, BMIz, and BMI%) than eligible non-participants. Conclusions: Schools using the opt-in recruitment were more likely to enroll at least 5 families and administer the intervention. However, the participation rate was higher in screen-first schools. The overall study sample was representative of the school demographics

Improving Project Logistics by using IoT

This Bachelor´s thesis is made on behalf of Wärtsilä Energy Solutions, Project Logistics & Transport Management department whose main task is to coordinate and ensure that materials and products are transported to the right place and on time in Project Logistics. This thesis examines how you could improve Wärtsilä´s Project Logistics by using Internet of Things. By developing IoT, there has been an increased chance to get more information about transports than before and Wärtsilä is currently looking for new solutions to use that could improve their current logistics system. The purpose of this thesis is to review new, and used, solutions on the market, and then see what could work in practice at Wärtsilä. Material to this thesis are gathered from books, web pages and articles that reviewed interesting IoT solutions and which also gave examples on different solutions that are used by other companies in the same business. The Result is two different methods that could improve Wärtsilä´s Project Logistics in different occasions. These results are intended to give tips on how IoT could improve the department´s ways of coordinating and check transports and logistics within a project.Detta examensarbete är gjort i uppdrag av Wärtsilä Energy Solutions, Project logistics & Transport Management avdelningen vars huvuduppgift är att koordinera och se till att material och produkter transporteras till rätt plats i rätt tid inom projekt logistiken. Examensarbetet behandlar hur man kunde förbättra Wärtsiläs projekt logistik genom att använda Internet of Things. Genom att IoT har utvecklats har det uppstått möjligheter att få fram mer information om transporter än tidigare och Wärtsilä söker för tillfället nya lösningar som kunde användas för att förbättra deras nuvarande logistiksystem. Syftet med arbetet är att gå igenom nya, men även redan befintliga, lösningar som används på dagens marknad - för att sedan se vad som kunde fungera i praktiken hos Wärtsilä. Material till arbetet är samlat från böcker, webbsidor och artiklar som gick igenom intressanta IoT lösningar och som också gav exempel på hur olika system fungerar och används av andra företag inom samma bransch. Slutresultatet blev två olika metoder som kunde förbättra Wärtsiläs projekt logistik vid olika tillfällen. Dessa resultat är tänkta för att ge tips på hur IoT kunde förbättra avdelningens sätt hur man koordinerar och granskar transporter och logistiken inom ett projekt