Operating manual for the RRL 8 channel data logger

A data collection device which takes measurements from external sensors at user specified time intervals is described. Three sensor ports are dedicated to temperature, air pressure, and dew point. Five general purpose sensor ports are provided. The user specifies when the measurements are recorded as well as when the information is read or stored in a minicomputer or a paper tape

Effects of cooling rate on structural relaxation in amorphous drugs: elastically collective nonlinear langevin equation theory and machine learning study

Theoretical approaches are formulated to investigate the molecular mobility under various cooling rates of amorphous drugs. We describe the structural relaxation of a tagged molecule as a coupled process of cage-scale dynamics and collective molecular rearrangement beyond the first coordination shell. The coupling between local and non-local dynamics behaves distinctly in different substances. Theoretical calculations for the structural relaxation time, glass transition temperature, and dynamic fragility are carried out over twenty-two amorphous drugs and polymers. Numerical results have a quantitatively good accordance with experimental data and the extracted physical quantities using the Vogel-Fulche-Tammann fit function and machine learning. The machine learning method reveals the linear relation between the glass transition temperature and the melting point, which is a key factor for pharmaceutical solubility. Our predictive approaches are reliable tools for developing drug formulations

Cocrystal habit engineering to improve drug dissolution and alter derived powder properties

YesObjectives: Cocrystallization of sulfadimidine (SDM) with suitable coformers, such as 4-aminosalicylic acid (4-ASA), combined with changes in the crystal habit can favourably alter its physicochemical properties. The aim of this work was to engineer SDM:4-ASA cocrystals with different habits in order to investigate the effect on dissolution, and the derived powder properties of flow and compaction. Methods: Cocrystals were prepared in a 1:1 molar ratio by solvent evaporation using ethanol (habit I) or acetone (habit II), solvent evaporation followed by grinding (habit III) and spray-drying (habit IV). Key findings: Powder X-ray diffraction showed Bragg peak position was the same in all the solid products. The peak intensity varied, indicating different preferred crystal orientation confirmed by SEM micrographs: large prismatic crystals (habit I), large plate-like crystals (habit II), small cube-like crystals (habit III) and microspheres (habit IV). The habit III exhibited the fasted dissolution rate; however, it underwent a polymorphic transition during dissolution. Habits I and IV exhibited the highest Carr’s compressibility index, indicating poor flowability. However, habits II and III demonstrated improved flow. Spray drying resulted in cocrystals with improved compaction properties. Conclusions: Even for cocrystals with poor pharmaceutical characteristics, a habit can be engineered to alter the dissolution, flowability and compaction behavior.Science Foundation Ireland. Grant Number: SFI/12/RC/227

The motivation to be sedentary predicts weight change when sedentary behaviors are reduced

<p>Abstract</p> <p>Background</p> <p>Obesity is correlated with a sedentary lifestyle, and the motivation to be active or sedentary is correlated with obesity. The present study tests the hypothesis that the motivation to be active or sedentary is correlated with weight change when children reduce their sedentary behavior.</p> <p>Methods</p> <p>The motivation to be active or sedentary, changes in weight, and accelerometer assessed physical activity were collected for 55 families with overweight/obese children who participated in a nine-week field study to examine behavior and weight change as a function of reducing sedentary behavior. Children were studied in three 3-week phases, baseline, reduce targeted sedentary behaviors by 25% and reduce targeted sedentary behaviors by 50%. The targeted sedentary behaviors included television, video game playing, video watching, and computer use.</p> <p>Results</p> <p>The reinforcing value of sedentary behavior but not physical activity, was correlated with weight change, as losing weight was associated with lower reinforcing value of sedentary behaviors. Reducing sedentary behavior was not associated with a significant change in objectively measured physical activity, suggesting the main way in which reducing sedentary behavior influenced weight change is by complementary changes in energy intake. Estimated energy intake supported the hypothesis that reducing sedentary behaviors influences weight by reducing energy intake.</p> <p>Conclusions</p> <p>These data show that the motivation to be sedentary limits the effects of reducing sedentary behavior on weight change in obese children.</p> <p>Trial registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00962247">NCT00962247</a></p

Experimental analysis of the effect of taxes and subsides on calories purchased in an on-line supermarket

Taxes and subsidies are a public health approach to improving nutrient quality of food purchases. While taxes or subsidies influence purchasing, it is unclear whether they influence total energy or overall diet quality of foods purchased. Using a within subjects design, selected low nutrient dense foods (e.g. sweetened beverages, candy, salty snacks) were taxed, and fruits and vegetables and bottled water were subsidized by 12.5% or 25% in comparison to a usual price condition for 199 female shoppers in an experimental store. Results showed taxes reduced calories purchased of taxed foods (coefficient = -6.61, Cl = -11.94 to -1.28) and subsidies increased calories purchased of subsidized foods (coefficient = 13.74, Cl = 8.51 to 18.97). However, no overall effect was observed on total calories purchased. Both taxes and subsidies were associated with a reduction in calories purchased for grains (taxes: coefficient = -6.58, Cl = -11.91 to -1.24, subsidies: coefficient = -12.86, Cl = -18.08 to -7.63) and subsidies were associated with a reduction in calories purchased for miscellaneous foods (coefficient = -7.40, CI = -12.62 to -2.17) (mostly fats, oils and sugars). Subsidies improved the nutrient quality of foods purchased (coefficient = 0.14, Cl = 0.07 to 0.21). These results suggest that taxes and subsidies can influence energy purchased for products taxed or subsidized, but not total energy purchased. However, the improvement in nutrient quality with subsidies indicates that pricing can shift nutritional quality of foods purchased. Research is needed to evaluate if differential pricing strategies based on nutrient quality are associated with reduction in calories and improvement in nutrient quality of foods purchased

Molecular relaxations in supercooled liquid and glassy states of amorphous gambogic acid: Dielectric spectroscopy, calorimetry, and theoretical approach

The relaxation dynamics and thermodynamic properties of supercooled and glassy gambogic acid are investigated using both theory and experiment. We measure the temperature dependence of the relaxation times in three polymorphs (α-, β-, and γ-form). To gain insight into the relaxation processes, we propose a theoretical approach to quantitatively understand the nature of these three relaxations. The α-relaxation captures cooperative motions of molecules, while the β-process is mainly governed by the local dynamics of a single molecule within the cage formed by its nearest neighbors. Based on quantitative agreement between theory and experimental data, our calculations clearly indicate that the β-process is a precursor of the structural relaxation and intramolecular motions are responsible for the γ-relaxation. Moreover, the approach is exploited to study the effects of the heating process on alpha relaxation. We find that the heating rate varies logarithmically with Tg and 1000/Tg . These variations are qualitatively consistent with many prior studies