Feasible, cost-effective instruments are required for the surveillance of moderate-to-vigorous physical activity (MVPA) and sedentary behaviour (SB) and to assess the effects of interventions. ...However, the evidence base for the validity and reliability of the World Health Organisation-endorsed Global Physical Activity Questionnaire (GPAQ) is limited. We aimed to assess the validity of the GPAQ, compared to accelerometer data in measuring and assessing change in MVPA and SB.
Participants (n = 101) were selected randomly from an on-going research study, stratified by level of physical activity (low, moderate or highly active, based on the GPAQ) and sex. Participants wore an accelerometer (Actigraph GT3X) for seven days and completed a GPAQ on Day 7. This protocol was repeated for a random sub-sample at a second time point, 3-6 months later. Analysis involved Wilcoxon-signed rank tests for differences in measures, Bland-Altman analysis for the agreement between measures for median MVPA and SB mins/day, and Spearman's rho coefficient for criterion validity and extent of change.
95 participants completed baseline measurements (44 females, 51 males; mean age 44 years, (SD 14); measurements of change were calculated for 41 (21 females, 20 males; mean age 46 years, (SD 14). There was moderate agreement between GPAQ and accelerometer for MVPA mins/day (r = 0.48) and poor agreement for SB (r = 0.19). The absolute mean difference (self-report minus accelerometer) for MVPA was -0.8 mins/day and 348.7 mins/day for SB; and negative bias was found to exist, with those people who were more physically active over-reporting their level of MVPA: those who were more sedentary were less likely to under-report their level of SB. Results for agreement in change over time showed moderate correlation (r = 0.52, p = 0.12) for MVPA and poor correlation for SB (r = -0.024, p = 0.916).
Levels of agreement with objective measurements indicate the GPAQ is a valid measure of MVPA and change in MVPA but is a less valid measure of current levels and change in SB. Thus, GPAQ appears to be an appropriate measure for assessing the effectiveness of interventions to promote MVPA.
A virtual cocrystal screening method based on calculated gas phase molecular electrostatic potential surfaces (MEPS) of the individual components has been validated using experimental cocrystal ...screens reported in the literature. The noncovalent interactions of a molecule with its environment are described by a discrete set of independent surface site interaction points (SSIPs), whose properties can be calculated from the ab initio MEPS. The stability of a crystal is estimated based on pairing SSIPs such that the sum of the pairwise interaction energies is optimized. This provides a means of calculating the relative stability of a cocrystal compared with the pure components without knowing anything about the three-dimensional structures of the crystalline states. For a set of potential crystal coformers (CCF), the difference between interaction site pairing energies of different solid forms (ΔE) provides a method for ranking CCFs based on the calculated probability of cocrystal formation. The method was applied to cocrystal screens of 18 compounds that reported both hits and misses, and in most cases, the virtual cocrystal screen reproduces experimental results well. In lists of CCFs ranked by ΔE, the experimentally observed hits were significantly enriched at the top, and this indicates that virtual screening is a promising tool for focusing experimental efforts on the most promising CCF candidates.
An oxidation flow reactor (OFR) is a vessel inside which the concentration of a chosen oxidant can be increased for the purpose of studying SOA formation and aging by that oxidant. During the ...BEACHON-RoMBAS (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics & Nitrogen–Rocky Mountain Biogenic Aerosol Study) field campaign, ambient pine forest air was oxidized by OH radicals in an OFR to measure the amount of SOA that could be formed from the real mix of ambient SOA precursor gases, and how that amount changed with time as precursors changed. High OH concentrations and short residence times allowed for semicontinuous cycling through a large range of OH exposures ranging from hours to weeks of equivalent (eq.) atmospheric aging. A simple model is derived and used to account for the relative timescales of condensation of low-volatility organic compounds (LVOCs) onto particles; condensational loss to the walls; and further reaction to produce volatile, non-condensing fragmentation products. More SOA production was observed in the OFR at nighttime (average 3 µg m−3 when LVOC fate corrected) compared to daytime (average 0.9 µg m−3 when LVOC fate corrected), with maximum formation observed at 0.4–1.5 eq. days of photochemical aging. SOA formation followed a similar diurnal pattern to monoterpenes, sesquiterpenes, and toluene+p-cymene concentrations, including a substantial increase just after sunrise at 07:00 local time. Higher photochemical aging (> 10 eq. days) led to a decrease in new SOA formation and a loss of preexisting OA due to heterogeneous oxidation followed by fragmentation and volatilization. When comparing two different commonly used methods of OH production in OFRs (OFR185 and OFR254-70), similar amounts of SOA formation were observed. We recommend the OFR185 mode for future forest studies. Concurrent gas-phase measurements of air after OH oxidation illustrate the decay of primary VOCs, production of small oxidized organic compounds, and net production at lower ages followed by net consumption of terpenoid oxidation products as photochemical age increased. New particle formation was observed in the reactor after oxidation, especially during times when precursor gas concentrations and SOA formation were largest. Approximately 4.4 times more SOA was formed in the reactor from OH oxidation than could be explained by the VOCs measured in ambient air. To our knowledge this is the first time that this has been shown when comparing VOC concentrations with SOA formation measured at the same time, rather than comparing measurements made at different times. Several recently developed instruments have quantified ambient semivolatile and intermediate-volatility organic compounds (S/IVOCs) that were not detected by a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS). An SOA yield of 18–58 % from those compounds can explain the observed SOA formation. S/IVOCs were the only pool of gas-phase carbon that was large enough to explain the observed SOA formation. This work suggests that these typically unmeasured gases play a substantial role in ambient SOA formation. Our results allow ruling out condensation sticking coefficients much lower than 1. These measurements help clarify the magnitude of potential SOA formation from OH oxidation in forested environments and demonstrate methods for interpretation of ambient OFR measurements.
Monolithic and packed‐bed reactors featuring immobilized catalysts are well‐precedented in continuous flow synthesis but can suffer from adverse pressure drops during use due to their small pore ...sizes and/or structural changes. Herein, we overcome this challenge with the synthesis of a structurally robust silica‐based monolith featuring pore sizes on the millimeter scale. The 3‐dimensional solid support structure is constructed from a polystyrene foam‐based template and features a functional group handle that can be modified to display a reactive catalyst. Here we functionalize the support with palladium(0) for hydrogenation reactions and a modified proline catalyst for the alpha functionalization of aldehydes. Both reactors showed good activity and excellent catalytic longevity when utilized under continuous flow conditions.
The evolution of atmospheric organic carbon as it undergoes oxidation has a controlling influence on concentrations of key atmospheric species, including particulate matter, ozone and oxidants. ...However, full characterization of organic carbon over hours to days of atmospheric processing has been stymied by its extreme chemical complexity. Here we study the multigenerational oxidation of α-pinene in the laboratory, characterizing products with several state-of-the-art analytical techniques. Although quantification of some early generation products remains elusive, full carbon closure is achieved (within measurement uncertainty) by the end of the experiments. These results provide new insights into the effects of oxidation on organic carbon properties (volatility, oxidation state and reactivity) and the atmospheric lifecycle of organic carbon. Following an initial period characterized by functionalization reactions and particle growth, fragmentation reactions dominate, forming smaller species. After approximately one day of atmospheric aging, most carbon is sequestered in two long-lived reservoirs-volatile oxidized gases and low-volatility particulate matter.
City planning policies influence urban lifestyles, health, and sustainability. We assessed policy frameworks for city planning for 25 cities across 19 lower-middle-income countries, ...upper-middle-income countries, and high-income countries to identify whether these policies supported the creation of healthy and sustainable cities. We systematically collected policy data for evidence-informed indicators related to integrated city planning, air pollution, destination accessibility, distribution of employment, demand management, design, density, distance to public transport, and transport infrastructure investment. Content analysis identified strengths, limitations, and gaps in policies, allowing us to draw comparisons between cities. We found that despite common policy rhetoric endorsing healthy and sustainable cities, there was a paucity of measurable policy targets in place to achieve these aspirations. Some policies were inconsistent with public health evidence, which sets up barriers to achieving healthy and sustainable urban environments. There is an urgent need to build capacity for health-enhancing city planning policy and governance, particularly in low-income and middle-income countries.
This paper presents a mechanically-robust high-power-density electromagnetic vibration energy harvester fabricated from MP35N alloy. Its primary focus is on the use of MP35N alloy, and the ...corresponding performance. It follows our prior work on a similar harvester fabricated in silicon that now provides a performance baseline. The optimized design flow developed in our prior work is applied here, yielding mechanical, electrical, and magnetic design decisions, and harvesting performance, that remain largely unchanged. Importantly, while supporting comparable harvesting performance, the new material significantly improves robustness and ruggedness as needed for practical applications. The MP35N harvester suspension is fabricated using a combination of water-jet and electrical-discharge machining. The resulting harvester has an active volume of 1.81 cm 3 , and an output power <inline-formula> <tex-math notation="LaTeX">P_{Out} </tex-math></inline-formula> of 1.26 mW at 1.08 g and 107.7 Hz under matched load. This yields a power density (PD) of 0.7 mW/cm 3 and a normalized power density (NPD) of 0.6 mW/cm 3 /g 2 . Importantly, the new harvester survives a 6-foot drop, and ordinary handling during fabrication and operation. The addition of backiron is shown to reduce magnetic-path reluctance, increase magnetic coupling, and thus increase output power. The harvester with backiron has an active volume of 2.17 cm 3 , and a <inline-formula> <tex-math notation="LaTeX">P_{Out} </tex-math></inline-formula> of 2.2 mW at 1.3 g under matched load, yielding a PD of 1.01 mW/cm 3 and an NPD of 0.6 mW/cm 3 /g 2 . 2020-0261
The objective was to evaluate whether routine aspirin 75 mg is more cost-effective than the Fetal Medicine Foundation screen-and-treat approach for preeclampsia prevention in low-risk nulliparous ...women. A health economic decision analytical model was devised to estimate the discounted net health and cost outcomes of routine aspirin versus Fetal Medicine Foundation screening test–indicated aspirin for a cohort of 100 000 low-risk nulliparous women. Both strategies were compared with no intervention. A subanalysis also compared disaggregated components of the algorithm. The analysis used data from hospital administration, literature, and a randomized controlled trial. Sensitivity analyses assessed the impact of aspirin adherence, test cost, and accuracy on study results. Presumed rates of preeclampsia were 3.75% with no intervention versus 0.45% with aspirin use. Results found that routine aspirin was the preferred strategy, in terms of greater health gains and larger cost savings. It provided 163 quality-adjusted life-years relative to no intervention, whereas the screen-and-treat policy achieved 108 quality-adjusted life-years. Routine aspirin would result in an estimated cost saving of 14.9 million annually relative to no intervention, whereas screen-and-treat approach would result in a smaller cost saving of 3.1 million. When the analysis was extended to consider alternative screen-and-treat strategies, routine aspirin remained the optimally cost-effective approach. In conclusion, routine aspirin use in low-risk nulliparous women has a greater health gain and cost saving compared with both the Fetal Medicine Foundation and other screen-and-treat approaches.
Cocrystal formation is considered as one of the most effective solid-state methods to alter the physicochemical properties of active pharmaceutical ingredients (APIs). In silico methods for cocrystal ...prediction are mostly based on structural and energetic considerations. We have developed a computational method that ranks the probability of cocrystal formation of APIs with large databases of crystal coformers (CCFs). This approach is based on using molecular electrostatic potential surfaces to assess molecular complementarity between two cocrystal components. The screening tool was applied to two low solubility drugs, namely griseofulvin and spironolactone. Promising coformer candidates were selected from a database of 310 pharmaceutically acceptable CCFs, and experimental screening was carried out. Novel solid forms were obtained by liquid-assisted grinding and were characterised by XRPD, DSC, TGA and IR. One new cocrystal of griseofulvin and two new cocrystals of spironolactone were identified, and the crystal structures were determined from the XRPD patterns. For these systems, phenols tend to act as successful H-bond donors in forming cocrystals, while carboxylic acids only give rise to physical mixtures of the two components.
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