714 results on '"Evans, Jack"'
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402. Grand Cathay's assets take a walk.
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Evans, Jack
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MERGERS & acquisitions law ,HOLDING companies ,NEW Taiwan dollar - Abstract
The article argues that the trouble with financial acquisitions is that the major assets of target institutions--the people--have two legs and will walk out if they do not like the new set-up. This happened on a big scale at Taiwan brokerage Grand Cathay Securities, which was bought by China Development Industrial Bank some months ago. It was the latest in a wave of industry consolidation triggered by new government legislation that allows the setting up of financial holding companies. The acquisition was part of the bank's plan to expand its presence in the market. Its core business is lending to corporates in industrial production. It has also handled equity and fixed income underwriting and has been involved with direct investment. Despite a sluggish market, Grand Cathay managed to complete a number of big New Taiwanese dollar (NT$) bond issues earlier in 2002. Chang Hwa Commercial Bank's NT$20 billion subordinated bank debenture, which Grand Cathay placed in just one week in March 2002, was the largest bank debenture issue ever by a commercial bank in Taiwan.
- Published
- 2002
403. Community Placement of the Mentally Retarded.
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Evans, Jack L.
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Reviews the book "Community Placement of the Mentally Retarded," by R. Mamula and N. Newman.
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- 1975
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404. Anion-π interactions of hexaaryl[3]radialenes
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Peter Hoffmann, Mark A. Buntine, Sandra Hack, Christopher J. Sumby, Jack D. Evans, Alexander S. Gentleman, Courtney A. Hollis, Evans, Jack D, Hollis, Courtney A, Hack, Sandra, Gentleman, Alexander S, Hoffmann, Peter, Buntine, Mark A, and Sumby, Christopher J
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anion receptor ,Anions ,Polymer science ,Molecular Structure ,Chemistry ,radialenes ,Quantum Theory ,Physical and Theoretical Chemistry ,Alkenes ,Mass Spectrometry - Abstract
Coordination polymers and discrete metallo-supramolecular assemblies of hexaaryl[3]radialene compounds exhibit intriguing structures with short anion to π-centroid distances in the solid-state. Furthermore, these [3]radialene compounds display useful photophysical and electrochemical properties that make them ideal as potential platforms for anion receptors. In this study, hexafluoro[3]radialene was optimized to the MP2/aug-cc-pVTZ level of theory, and its complexes with halide anions were optimized to HF/6-31G++(d,p), MP2/6-31G++(d,p), M06-2X/6-31G++(d,p), and M06-2X/6-311G++(d,p) levels of theory. Hexafluoro[3]radialene was shown to have properties (large positive Qzz and areas of positive electrostatic surface potential) comparable to other compounds that show anion-π interactions. The interaction energies of complexes of hexafluoro[3]radialene with halide anions were calculated and found to be favorable and equivalent to those of fluorinated aromatic compounds. A series of synthetically accessible hexaaryl[3]radialenes were optimized to HF/6-31G++(d,p) theory and their complexes with halides optimized to the M06-2X/6-31G++(d,p) level of theory. The calculated properties of the electron-deficient hexaaryl[3]radialenes also show large positive Qzz quadrupole moments and two areas of positive potential; at the [3]radialene core and the acidic aryl hydrogen atoms. The interaction energies of the complexes of hexaaryl[3]radialenes and halide anions were found to follow the trend F- > Cl- ≈ Br- and correlate with the electron-deficient nature of the [3]radialene. Close contacts were observed between the anion and the radialene core and the aryl hydrogen atoms, suggesting a combination of anion-π and hydrogen bonding is important. Mass spectrometry was used to experimentally observe the complexes of a number of hexaaryl[3]radialenes with F-, Cl-, and Br- predicted computationally. Anion-[3]radialene complexes were successfully detected, and the stability of the complexes in tandem MS/MS experiments was found to support the computational results. Refereed/Peer-reviewed
- Published
- 2012
405. Melanin concentrating hormone projections to the nucleus accumbens enhance the reward value of food consumption and do not induce feeding or REM sleep.
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Furman KL, Baron L, Lyons HC, Cha T, Evans JR, Manna J, Zhu L, Mattis J, and Burgess CR
- Abstract
Regulation of food intake and energy balance is critical to survival. Hunger develops as a response to energy deficit and drives food-seeking and consumption. However, motivations to eat are varied in nature, and promoted by factors other than energy deficit. When dysregulated, non-homeostatic drives to consume can contribute to disorders of food intake, adding to the increasing prevalence of restrictive eating disorders and obesity. Melanin-concentrating hormone (MCH) neurons have been implicated in the regulation of feeding behavior, in addition to a number of other fundamental behaviors including sleep, anxiety, and maternal behavior. Several studies suggest that MCH peptide increases food consumption, while studies of MCH neurons show effects only on cued feeding, and others show no effect of MCH neuron manipulation on feeding. MCH neurons have widespread projections to diverse downstream brain regions yet few studies have investigated the function of specific projections or differentiated the behaviors they regulate. Here we use optogenetics, in combination with different behavioral paradigms, to elucidate the role of MCH projections to the nucleus accumbens (NAc) in sleep and feeding behavior. We show that MCH neurons projecting to the NAc do not induce changes in baseline feeding or REM sleep, but do enhance the preference for a food paired with optogenetic stimulation. Furthermore, this effect is diminished in female mice relative to males, in line with previous results suggesting sex differences in the functional role of MCH neurons. These results suggest that MCH projections to the NAc can enhance the rewarding value of consumed food., Significance Statement: While feeding is often driven by hunger, there are non-homeostatic reasons why animals consume food. Melanin-concentrating hormone (MCH) neurons have been implicated in the regulation of many fundamental behaviors, including feeding, sleep and reward. They project broadly throughout the brain, suggesting that they may mediate this diverse set of behaviors independently via specific projections to downstream regions. We used optogenetic activation of MCH neurons and their projections to the nucleus accumbens (NAc) in combination with complex behavioral paradigms to demonstrate that MCH projections to the NAc do not induce baseline feeding or increases in REM sleep but do enhance the value of a paired food. These results suggest that MCH neurons contribute to non-homeostatic consumption via projections to the NAc.
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- 2024
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406. Life-period associations of body mass index with adult carotid intima-media thickness: The Bogalusa Heart Study and the Cardiovascular Risk in Young Finns Study.
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Evans JT, Buscot MJ, Fraser BJ, Juonala M, Guo Y, Fernandez C, Kähönen M, Sabin MA, Armstrong MK, Viikari JSA, Bazzano LA, Raitakari OT, and Magnussen CG
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Objective: Child and adult body mass index (BMI) associates with adult carotid artery intima-media thickness (cIMT). However, the relative contribution of BMI at different life-periods on adult cIMT has not been quantified. This study aimed to determine the life-course model that best explains the relative contribution of BMI at different life-periods (childhood, adolescence, and young-adulthood) on cIMT in adulthood., Methods: BMI was calculated from direct measurements of height and weight at up to seven time-points from childhood to adulthood (1973-2007) among 2485 participants of the Cardiovascular Risk in Young Finns Study (YFS) and 1271 participants in the Bogalusa Heart Study (BHS). BMI measures at three ages representative of childhood (9-years), adolescence (18 years) and young-adulthood (30 years) life-periods were used. B-mode ultrasound was used to measure common cIMT in adulthood (>30 years). Associations were evaluated using the Bayesian relative life-course exposure model., Results: In both cohorts, cumulative exposure to higher levels of BMI across the life-course was associated with greater cIMT. Of the examined life-periods, BMI in young-adulthood provided the greatest relative contribution towards the development of adult cIMT for YFS (49.9 %, 95 % CrI = 34-68 %) and white BHS participants (48.6 %, 95 % CrI = 9-86 %), whereas BMI in childhood had the greatest relative contribution for black BHS participants (54.0 %, 95 % CrI = 8-89 %)., Conclusion: Although our data suggest sensitive periods in the life-course where prevention and intervention aimed at reducing BMI might provide most benefit in limiting the effects of BMI on cIMT, maintaining lower BMI across the life-course appears to be optimal., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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407. Is public transport a promising strategy for increasing physical activity? Evidence from a study of objectively measured public transport use and physical activity.
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Evans JT, Stanesby O, Blizzard L, Greaves S, Timperio A, Jose K, Sharman MJ, Palmer AJ, and Cleland VJ
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- Humans, Male, Female, Adult, Longitudinal Studies, Middle Aged, Tasmania, Australia, Exercise, Transportation methods, Sedentary Behavior, Accelerometry
- Abstract
Background: Greater public transport use has been linked to higher physical activity levels. However, neither the amount of physical activity associated with each daily public transport trip performed, nor the potential total physical activity gain associated with an increase in trips/day, has been determined. Using objective measures, we aimed to quantify the association between public transport use, physical activity and sedentary time., Methods: A longitudinal study of Australian adults living in Hobart, Tasmania, who were infrequent bus users (≥ 18 years; used bus ≤ 2 times/week). The number of bus trips performed each day was determined from objective smartcard data provided by the public transportation (bus) provider across a 36-week study timeframe. Accelerometer measured steps/day (primary outcome), moderate-to-vigorous physical activity (min/day), and sedentary time (min/day) were assessed across four separate one-week periods., Results: Among 73 participants across 1483 day-level observations, on days that public transport was used, participants achieved significantly more steps (β = 2147.48; 95%CI = 1465.94, 2829.03), moderate to vigorous physical activity (β = 22.79; 95% CI = 14.33, 31.26), and sedentary time (β = 37.00; 95% CI = 19.80, 54.21) compared to days where no public transport trips were made. The largest increase in steps per day associated with a one-trip increase was observed when the number of trips performed each day increased from zero to one (β = 1761.63; 95%CI = 821.38, 2701.87). The increase in the number of steps per day was smaller and non-significant when the number of trips performed increased from one to two (β = 596.93; 95%CI=-585.16, 1779.01), and two to three or more (β = 632.39; 95%CI=-1331.45, 2596.24) trips per day. Significant increases in sedentary time were observed when the number of trips performed increased from zero to one (β = 39.38; 95%CI = 14.38, 64.39) and one to two (β = 48.76; 95%CI = 25.39, 72.12); but not when bus trips increased from two to three or more (β=-27.81; 95%CI=-76.00, 20.37)., Conclusions: Greater public transport use was associated with higher physical activity and sedentary behaviour. Bus use may yield cumulative increases in steps that amount to 15-30% of the daily recommended physical activity target. A policy and public health focus on intersectoral action to promote public transport may yield meaningful increases in physical activity and subsequent health benefits., (© 2024. The Author(s).)
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- 2024
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408. Self-Sorting of Interfacial Compatibility in MOF-Based Mixed Matrix Membranes.
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Qi A, Li C, Evans JD, Zhao Y, and Li T
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Metal-organic framework (MOF)-based mixed matrix membranes (MMMs) have shown great promises to overcome the performance upper limit of polymeric membranes for various gas separation processes. However, the gas separation properties of the MMMs largely depend on the MOF-polymer interfacial compatibility which is a metric difficult to quantify. In most cases, whether a MOF filler and a polymer matrix make a good pair is not revealed until the gas transport experiments are performed. This is because there is a lack of characterization techniques to directly probe the MOF-polymer interfacial compatibility. In this work, we demonstrate a self-sorting method to rank the interface compatibility among several MOF-polymer pairs. By mixing one MOF with two polymers in an MMM, the demixing of two polymers will form two polymer domains. The MOF particles will preferably partition into the "preferred" polymer domain due to their higher interfacial affinity. By scanning different polymer pairs, a rank of MOF-polymer interfacial compatibility from high to low can be obtained. Moreover, based on this ranking, it was also found that a highly compatible MOF-polymer pair suggested by this method also corresponds to a more predictable MMM gas separation performance., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)
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- 2024
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409. The use of collective variables and enhanced sampling in the simulations of existing and emerging microporous materials.
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Stracke K and Evans JD
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Microporous materials, including zeolites, metal-organic frameworks, and cage compounds, offer diverse functionalities due to their unique dynamics and guest confinement properties. These materials play a significant role in separation, catalysis, and sensing, but their complexity hinders exploration using traditional atomistic simulations. This review explores collective variables (CVs) paired with enhanced sampling as a powerful approach to enable efficient investigation of key features in microporous materials. We highlight successful applications of CVs in studying adsorption, diffusion, phase transitions, and mechanical properties, demonstrating their crucial role in guiding material design and optimisation. The future of CVs lies in integration with techniques like machine learning, allowing for enhanced efficiency and accuracy. By tailoring CVs to specific materials and developing multi-scale approaches we can further unlock the intricacies of these fascinating materials. Simulations are a cornerstone in unravelling the complexities of microporous materials and are crucial for our future understanding.
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- 2024
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410. The rise of data repositories in materials chemistry.
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Stracke K and Evans JD
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- 2024
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411. Determining pathways of effect between correlates and outcomes of transport-related physical activity at differing timepoints across the lifecourse: A structural equation modelling approach.
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Evans JT, Buscot MJ, Gall S, Dwyer T, Venn A, and Cleland V
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- Adult, Child, Humans, Latent Class Analysis, Australia, Educational Status, Exercise, Smoking epidemiology
- Abstract
Transport-related physical activity levels differ across the lifecourse; however, the nature of these differences is poorly understood. This study examined the relationship between correlates of transport-related physical activity and how they differ in strength, pathway, and direction across the lifecourse. Structural Equation Modelling assessed relationships between correlates (e.g., age, smoking, education) and transport-related physical activity (assessed via the International Physical Activity Questionnaire) at four timepoints of the Australian Childhood Determinants of Adult Health study: childhood (7-15y; n = 6302), early-adulthood (26-36y; n = 2700), early/mid-adulthood (31-41y; n = 1649), and mid-adulthood (36-49y; n = 1794). Several pathways were consistent across the lifecourse. Self-rated health directly associated with transport-related physical activity across all timepoints. During adulthood greater body mass index and smoking frequency were indirectly associated with lower levels of transport-related physical activity via self-rated health; similarly, lower educated adults, who smoked more frequently, and had poorer health, had lower transport-related physical activity. Urban residence was directly associated with greater transport-related physical activity in childhood and early-adulthood; having more children in early/mid- and mid-adulthood was directly associated with less transport-related physical activity. This is the first study to report pathways of direct and indirect association between correlates and transport-related physical activity at key lifecourse stages. The pathways highlighted can inform policy and practice to aid in the development of age-specific lifecourse interventions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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412. A Lantern-Shaped Pd(II) Cage Constructed from Four Different Low-Symmetry Ligands with Positional and Orientational Control: An Ancillary Pairings Approach.
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Preston D and Evans JD
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One of the key challenges of metallo-supramolecular chemistry is to maintain the ease of self-assembly but, at the same time, create structures of increasingly high levels of complexity. In palladium(II) quadruply stranded lantern-shaped cages, this has been achieved through either 1) the formation of heteroleptic (multi-ligand) assemblies, or 2) homoleptic assemblies from low-symmetry ligands. Heteroleptic cages formed from low-symmetry ligands, a hybid of these two approaches, would add an additional rich level of complexity but no examples of these have been reported. Here we use a system of ancillary complementary ligand pairings at the termini of cage ligands to target heteroleptic assemblies: these complementary pairs can only interact (through coordination to a single Pd(II) metal ion) between ligands in a cis position on the cage. Complementarity between each pair (and orthogonality to other pairs) is controlled by denticity (tridentate to monodentate or bidentate to bidentate) and/or hydrogen-bonding capability (AA to DD or AD to DA). This allows positional and orientational control over ligands with different ancillary sites. By using this approach, we have successfully used low-symmetry ligands to synthesise complex heteroleptic cages, including an example with four different low-symmetry ligands., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)
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- 2023
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413. Atomic-Scale Elucidation of Unusually Distorted Dimeric Complexes Confined in a Zr-Based Metal-Organic Framework.
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Gimeno-Fonquernie P, Albalad J, Evans JD, Price J, Doonan CJ, and Sumby CJ
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Nanoconfinement in metal-organic framework (MOF) pores can lead to the isolation of unusual or reactive metal complexes. However, MOFs that support the stabilization and precise structural elucidation of metal complexes and small metal clusters are rare. Here, we report a thermally and chemically stable zirconium-based MOF (University of Adelaide Material-1001, UAM-1001) with a high density of free bis-pyrazolyl units that can confine mono- and dinuclear metal complexes. The precursor MOF, UAM-1000, has a high degree of structural flexibility, but post synthetic modification with a bracing linker, biphenyl-4,4'-dicarboxylic acid, partially rigidifies the MOF (UAM-1001). This allows "matrix isolation" and detailed structural elucidation of postsynthetically added dimeric complexes bound within a tetradentate binding site formed by two linkers. Dimeric species [Co
2 Cl4 ], [Cu2 Cl4 ], [Ni2 Cl3 (H2 O)2 ]Cl, and [Rh2 (CO)3 Cl2 ] were successfully isolated in UAM-1001 and characterized by single-crystal X-ray diffraction. Comparison of the UAM-1001 isolated species with similar complexes in the solid state reveals that UAM-1001 can significantly distort the structures and enforce notably shorter metal-metal distances. For example, MOF tethering allows isolation of a [Cu2 Cl4 ] complex that rapidly reacts with water in the solid state. The stability, porosity, and modulated flexibility of UAM-1001 provide an ideal platform material for the isolation and study of new dimeric complexes and their reactivity.- Published
- 2023
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414. trips4health: a single-blinded randomised controlled trial incentivising adult public transport use for physical activity gain.
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Evans JT, Stanesby O, Blizzard L, Jose K, Sharman MJ, Ball K, Greaves S, Palmer AJ, Cooper K, Gall SL, and Cleland VJ
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- Humans, Adult, Australia, Motivation, Exercise, Walking, COVID-19
- Abstract
Background: Public transport users tend to accumulate more physical activity than non-users; however, whether physical activity is increased by financially incentivising public transport use is unknown. The trips4health study aimed to determine the impact of an incentive-based public transport intervention on physical activity., Methods: A single-blinded randomised control trial of a 16-week incentive-based intervention involved Australian adults who were infrequent bus users (≥ 18 years; used bus ≤ 2 times/week) split equally into intervention and control groups. The intervention group were sent weekly motivational text messages and awarded smartcard bus credit when targets were met. The intervention group and control group received physical activity guidelines. Accelerometer-measured steps/day (primary outcome), self-reported transport-related physical activity (walking and cycling for transport) and total physical activity (min/week and MET-min/week) outcomes were assessed at baseline and follow-up., Results: Due to the COVID pandemic, the trial was abandoned prior to target sample size achievement and completion of all assessments (N = 110). Steps/day declined in both groups, but by less in the intervention group [-557.9 steps (-7.9%) vs.-1018.3 steps/week (-13.8%)]. In the intervention group, transport-related physical activity increased [80.0 min/week (133.3%); 264.0 MET-min/week (133.3%)] while total physical activity levels saw little change [35.0 min/week (5.5%); 25.5 MET-min/week (1.0%)]. Control group transport-related physical activity decreased [-20.0 min/week (-27.6%); -41.3 MET-min/week (-17.3%)], but total physical activity increased [260.0 min/week (54.5%); 734.3 MET-min/week (37.4%)]., Conclusion: This study found evidence that financial incentive-based intervention to increase public transport use is effective in increasing transport-related physical activity These results warrant future examination of physical activity incentives programs in a fully powered study with longer-term follow-up., Trial Registration: This trial was registered with the Australian and New Zealand Clinical Trials Registry August 14th, 2019: ACTRN12619001136190; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=377914&isReview=true., (© 2023. BioMed Central Ltd., part of Springer Nature.)
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- 2023
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415. Sex-specific differences in the efficacy of heart failure therapies: a meta-analysis of 84,818 patients.
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Wang N, Evans J, Sawant S, Sindone J, and Lal S
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- Male, Female, Humans, Ivabradine, Angiotensin Receptor Antagonists, Stroke Volume, Angiotensins, Sex Characteristics, Heart Failure drug therapy
- Abstract
Women have been historically underrepresented in clinical trials of heart failure (HF). We aimed to assess for sex differences in patient characteristics and the efficacy of guideline-directed medical therapy (GDMT) in HF. Systematic literature search for randomized controlled trials (RCTs) of GDMT reporting cardiovascular outcomes by sex in patients with HF. The primary outcome was the composite of cardiovascular death and hospitalization for HF. Risk ratios (RR) with 95% confidence intervals (CI) were pooled using inverse variance weighting and random effects meta-analysis. Twenty-six RCTs totaling 84,818 participants (27% women) were included. Women with HF were older, had higher New York Heart Association (NYHA) class, more hypertension and obesity, and higher mean left ventricular ejection fraction compared to men. There was evidence for most GDMT in reducing the primary outcome in women with HF with reduced ejection fraction (HFrEF) (angiotensin-converting enzyme inhibitors/angiotensin-receptor blocker [RR 0.86, 95% CI 0.75-0.97], angiotensin-receptor blocker/neprilysin inhibitor (ARNI) [RR 0.77, 95% CI 0.62-0.94], beta-blocker [RR 0.67, 95% CI 0.51-0.89], ivabradine [RR 0.74, 95% CI 0.60-0.91], and sodium-glucose cotransporter-2 (SGLT2) inhibitors [RR 0.66, 95% CI 0.54-0.81]) and a non-significant trend for benefit with mineralocorticoid-receptor-antagonist (MRA) [RR 0.77, 95% CI 0.52-1.16]). Compared to men with HFrEF, GDMT reduced the primary outcome in women to a similar degree across all drug classes (ratio of RR 1.05, 95% CI 0.96-1.14). Despite differences in baseline characteristics and an underrepresentation of women in HF clinical trials, GDMT are as efficacious in women as compared to men in reducing cardiovascular events in HF., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2023
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416. On the role of history-dependent adsorbate distribution and metastable states in switchable mesoporous metal-organic frameworks.
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Walenszus F, Bon V, Evans JD, Krause S, Getzschmann J, Kaskel S, and Dvoyashkin M
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A unique feature of metal-organic frameworks (MOFs) in contrast to rigid nanoporous materials is their structural switchabilty offering a wide range of functionality for sustainable energy storage, separation and sensing applications. This has initiated a series of experimental and theoretical studies predominantly aiming at understanding the thermodynamic conditions to transform and release gas, but the nature of sorption-induced switching transitions remains poorly understood. Here we report experimental evidence for fluid metastability and history-dependent states during sorption triggering the structural change of the framework and leading to the counterintuitive phenomenon of negative gas adsorption (NGA) in flexible MOFs. Preparation of two isoreticular MOFs differing by structural flexibility and performing direct in situ diffusion studies aided by in situ X-ray diffraction, scanning electron microscopy and computational modelling, allowed assessment of n-butane molecular dynamics, phase state, and the framework response to obtain a microscopic picture for each step of the sorption process., (© 2023. The Author(s).)
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- 2023
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417. Fabrication of 3D Oriented MOF Micropatterns with Anisotropic Fluorescent Properties.
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Velásquez-Hernández MJ, Linares-Moreau M, Brandner LA, Marmiroli B, Barella M, Acuna GP, Zilio SD, Verstreken MFK, Kravchenko DE, Linder-Patton OM, Evans JD, Wiltsche H, Carraro F, Wolinski H, Ameloot R, Doonan C, and Falcaro P
- Abstract
Micropatterning crystalline materials with oriented pores is necessary for the fabrication of devices with anisotropic properties. Crystalline and porous metal-organic frameworks (MOFs) are ideal materials as their chemical and structural mutability enables precise tuning of functional properties for applications ranging from microelectronics to photonics. Herein, a patternable oriented MOF film is designed: by using a photomask under X-ray exposure, the MOF film decomposes in the irradiated areas, remaining intact in the unexposed regions. The MOF film acts simultaneously as a resist and as functional porous material. While the heteroepitaxial growth from aligned Cu(OH)
2 nanobelts is used to deposit oriented MOF films, the sensitivity to radiation is achieved by integrating a brominated dicarboxylate ligand (Br2 BDC) into a copper-based MOF Cu2 L2 DABCO (DABCO = 1,4-diazabicyclo[2.2.2]octane; L = BDC/Br2 BDC). The lithographed samples act as diffraction gratings upon irradiation with a laser, thus confirming the quality of the extended MOF micropattern. Furthermore, the oriented MOF patterns are functionalized with fluorescent dyes. As a result, by rotating the polarization angle of the laser excitation, the alignment of the dye in the MOF is demonstrated. By controlling the functional response to light, this MOF patterning protocol can be used for the microfabrication of optical components for photonic devices., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)- Published
- 2023
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418. Distinct patterns of adult transport-related physical activity (TRPA) behaviour exist independent of the TRPA behaviours of childhood: the childhood determinants of adult health study.
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Evans JT, Buscot MJ, Gall S, Dwyer T, Venn A, and Cleland V
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- Adult, Humans, Australia, Longitudinal Studies, Risk, Exercise
- Abstract
Background: Transport-related physical activity (TRPA) is recognised as a potential means of increasing total physical activity participation that may yield substantial health benefits. Public health campaigns focusing on promoting TRPA from a young age aim to develop life-long healthy habits. However, few studies have examined how TRPA changes across the lifecourse and whether childhood TRPA levels influence those observed later in life., Methods: Using the Australian Childhood Determinants of Adult Health study (baseline, 1985), latent class growth mixture modelling with adjustment for time-varying covariates was performed using four timepoints (ranging from 7 to 49 years) to assess behavioural patterns and retention of TRPA across the lifecourse. As child and adult adjusted TRPA measures could not be harmonised, trajectories of adult TRPA (n = 702) were instead identified, and log-binomial regression analysis was performed to determine whether childhood levels of TRPA (high/medium/low) influenced these trajectories., Results: Two stable groups of adult TRPA trajectories were identified: persistently low (n = 520; 74.2%), and increasingly high TRPA (n = 181; 25.8%). There was no significant relationship between childhood TRPA levels and patterns in adulthood (relative risk of high childhood TRPA yielding high adult TRPA trajectory membership = 1.06; 95% confidence interval = 0.95-1.09)., Conclusion: This study found childhood TRPA levels were not associated with TRPA patterns in adulthood. These findings suggest that while TRPA in childhood may have health, social, and environmental benefits, it does not appear to impact adult TRPA directly. Therefore, further intervention is required beyond childhood to promote the implementation of healthy TRPA behaviours into adulthood., (© 2023. The Author(s).)
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- 2023
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419. Using immersive virtual reality to remotely examine performance differences between dominant and non-dominant hands.
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Evans JO, Tsaneva-Atanasova K, and Buckingham G
- Abstract
Circle drawing may be a useful task to study upper-limb function in patient populations. However, previous studies rely on expensive and bulky robotics to measure performance. For clinics or hospitals with limited budgets and space, this may be unfeasible. Virtual reality (VR) provides a portable and low-cost tool with integrated motion capture. It offers potentially a more feasible medium by which to assess upper-limb motor function. Prior to use with patient populations, it is important to validate and test the capabilities of VR with healthy users. This study examined whether a VR-based circle drawing task, completed remotely using participant's own devices, could capture differences between movement kinematics of the dominant and non-dominant hands in healthy individuals. Participants ( n = 47) traced the outline of a circle presented on their VR head-mounted displays with each hand, while the positions of the hand-held controllers were continuously recorded. Although there were no differences observed in the size or roundness of circles drawn with each hand, consistent with prior literature our results did show that the circles drawn with the dominant hand were completed faster than those with the non-dominant hand. This provides preliminary evidence that a VR-based circle drawing task may be a feasible method for detecting subtle differences in function in clinical populations., Supplementary Information: The online version contains supplementary material available at 10.1007/s10055-023-00794-z., Competing Interests: Conflict of interestThe authors have no relevant financial or non-financial interests to disclose., (© The Author(s) 2023.)
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- 2023
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420. Particle size-dependent flexibility in DUT-8(Cu) pillared layer metal-organic framework.
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Maliuta M, Senkovska I, Thümmler R, Ehrling S, Becker S, Romaka V, Bon V, Evans JD, and Kaskel S
- Abstract
The nature of metal in the isomorphous flexible metal-organic frameworks is often reported to influence flexibility and responsivity. A prominent example of such behaviour is the DUT-8( M ) family ([ M
2 (2,6-ndc)2 (dabco)]n , 2,6-ndc = 2,6-naphthalene dicarboxylate, dabco = 1,4-diazabicyclo-[2.2.2]-octane), where the isostructural compounds with Ni, Zn, Co, and Cu in the paddle wheel cluster are known. The macro-sized crystals of Ni, Co, and Zn based compounds transform to the closed pore (cp) phase under desolvation and show typical gate opening behaviour upon adsorption. The choice of metal, in this case, allows the adjustment of switching kinetics, selectivity in adsorption, and gate-opening pressures. The submicron-sized crystals of of Ni, Co, and Zn based compounds remain in the open pore (op) phase after desolvation. In this contribution, we demonstrate that the presence of Cu in the paddle wheel leads to fundamentally different flexible behaviour. The DUT-8(Cu) desolvation does not lead to the formation of the cp phase, independent of the particle size regime. However, according to in situ powder diffraction analysis, the desolvated, macro-sized crystals of DUT-8(Cu)_op show breathing upon adsorption of CO2 at 195 K. The submicron-sized particles show rigid, nonresponsive behaviour.- Published
- 2023
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421. Ultrabroadband plasmon driving selective photoreforming of methanol under ambient conditions.
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Uddin N, Sun Z, Langley J, Lu H, Cao P, Wibowo A, Yin X, Tang CS, Nguyen HT, Evans JD, Li X, Zhang X, Heggen M, Dunin-Borkowski RE, Wee ATS, Zhao H, Cox N, and Yin Z
- Abstract
Liquid methanol has the potential to be the hydrogen energy carrier and storage medium for the future green economy. However, there are still many challenges before zero-emission, affordable molecular H
2 can be extracted from methanol with high performance. Here, we present noble-metal-free Cu-WC/W plasmonic nanohybrids which exhibit unsurpassed solar H2 extraction efficiency from pure methanol of 2,176.7 µmol g-1 h-1 at room temperature and normal pressure. Macro-to-micro experiments and simulations unveil that local reaction microenvironments are generated by the coperturbation of WC/W's lattice strain and infrared-plasmonic electric field. It enables spontaneous but selective zero-emission reaction pathways. Such microenvironments are found to be highly cooperative with solar-broadband-plasmon-excited charge carriers flowing from Cu to WC surfaces for efficient stable CH3 OH plasmonic reforming with C3 -dominated liquid products and 100% selective gaseous H2 . Such high efficiency, without any COx emission, can be sustained for over a thousand-hour operation without obvious degradation.- Published
- 2023
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422. Temperature Driven Transformation of the Flexible Metal-Organic Framework DUT-8(Ni).
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Ehrling S, Senkovska I, Efimova A, Bon V, Abylgazina L, Petkov P, Evans JD, Gamal Attallah A, Wharmby MT, Roslova M, Huang Z, Tanaka H, Wagner A, Schmidt P, and Kaskel S
- Abstract
DUT-8(Ni) metal-organic framework (MOF) belongs to the family of flexible pillared layer materials. The desolvated framework can be obtained in the open pore form (op) or in the closed pore form (cp), depending on the crystal size regime. In the present work, we report on the behaviour of desolvated DUT-8(Ni) at elevated temperatures. For both, op and cp variants, heating causes a structural transition, leading to a new, crystalline compound, containing two interpenetrated networks. The state of the framework before transition (op vs. cp) influences the transition temperature: the small particles of the op phase transform at significantly lower temperature in comparison to the macroparticles of the cp phase, transforming close to the decomposition temperature. The new compound, confined closed pore phase (ccp), was characterized by powder X-ray diffraction and spectroscopic techniques, such as IR, EXAFS, and positron annihilation lifetime spectroscopy (PALS). Thermal effects of structural transitions were studied using differential scanning calorimetry (DSC), showing an overall exothermic effect of the process, involving bond breaking and reformation. Theoretical calculations reveal the energetics, driving the observed temperature induced phase transition., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)
- Published
- 2022
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423. A Switchable Palladium(II) Trefoil Entangled Tetrahedron with Temperature Dependence and Concentration Independence.
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Algar JL, Findlay JA, Evans JD, and Preston D
- Abstract
Self-assembly makes metallo-interlocked architectures attractive targets, but being in equilibrium with smaller species means that they can suffer from dilution effects. We show that a junctioned system gives rise to a [Pd
4 (L)2 ]8+ trefoil entangled tetrahedron irrespective of concentration. Heating the sample reversibly shifts the equilibrium from the knot to an isomeric non-interlocked dual metallo-cycle, demonstrating that thermodynamic equilibria can still be exploited for switching even in the absence of concentration effects., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)- Published
- 2022
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424. Exploring General Practitioners' Preferences and Experience with Respiratory Inhaler Devices.
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Cvetkovski B, Hespe C, House R, Kritikos V, Azzi E, Evans J, Srour-Alphonse P, and Bosnic-Anticevich S
- Abstract
Introduction: Correct inhaler technique is essential for the optimal delivery of inhaled medicines and the successfully management of respiratory conditions. The general practitioner (GP), the prescriber of inhaled medicines, plays a crucial role in educating patients on inhaler technique. However, in the real-world setting, there are barriers. For the GP, it is time and competence and for the patient, it is their ability to recognise inhaler technique as an issue and their ability to maintain correct inhaler technique over time. This study aimed to determine GPs' experience, skills and priority placed on inhaler technique and to identify factor(s) associated with inhaler technique competence., Methods: This cross-sectional observational study design surveyed GPs' perspectives on inhaler use and preferences for inhaler prescribing within their practice setting. GP inhaler technique was assessed. GPs were recruited through an established network of GP practices. Data collected include (i) practice demographics, (ii) inhaler technique opinions and experience, (iii) inhaler prescribing preferences and (iv) inhaler education history data. Data were analysed descriptively and multivariate logistic regression modelling was used to explore the relationship between outcomes and GPs' ability to use devices correctly., Results: A total of 227 GPs completed the inhaler survey. Sixty-three percent of GPs reported receiving previous inhaler education and 73.3% educated or checked their patients' inhaler technique; 64.5% felt they were somewhat competent in doing so. GPs who reported not demonstrating inhaler technique believed that a pharmacist or a practice nurse would do so. When prescribing new inhaler devices, GPs considered the disease being treated first and then patient's experience with inhalers; they often already have an inhaler preference and this was related to familiarity and perceived ease of use. For GPs, inhaler competence was not associated with their previous inhaler education or the priority placed on inhaler technique., Conclusion: GPs do recognise the importance of inhaler technique in respiratory management but their technique can be better supported with regular educational updates to inform them about new inhalers and management practices and to support appropriate inhaler choices for their patients., (© 2022. The Author(s).)
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- 2022
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425. Correlates and determinants of transport-related physical activity among adults: an interdisciplinary systematic review.
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Evans JT, Phan H, Buscot MJ, Gall S, and Cleland V
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- Adult, Cross-Sectional Studies, Humans, Self Efficacy, Transportation, Exercise, Social Environment
- Abstract
Introduction: Transport-related physical activity (TRPA) has been identified as a way to increase physical activity due to its discretionary and habitual nature. Factors thought to influence TRPA span multiple disciplines and are rarely systematically considered in unison. This systematic review aimed to identify cross-sectional and longitudinal factors associated with adult TRPA across multiple research disciplines., Methods: Using four electronic databases, a systematic search of English, peer-reviewed literature from 2010 - 2020 was performed. Studies quantitatively examining factors associated with the outcome of adult TRPA were eligible., Results: Seventy-three studies (n = 66 cross-sectional; n = 7 longitudinal) were included, cumulatively reporting data from 1,278,632 observations. Thirty-six factors were examined for potential association with TRPA and presented in a social-ecological framework: individual (n = 15), social (n = 3), and environmental (n = 18). Seven factors were found to be consistently associated with higher adult TRPA: lower socio-economic status, higher self-efficacy, higher social normalization, lower distance of travel, higher destination concentration, more streetlighting, and higher public transportation frequency with a greater number of terminals near route start and endpoints., Conclusions: This is the first comprehensive compilation of the correlates and determinants of adult TRPA. Seven individual, social, and environmental factors demonstrated consistent associations with TRPA. Models formed using these factors may facilitate more effective promotion of TRPA. There is a lack of longitudinal studies as well as studies assessing cognitive/attitudinal and social factors, highlighting gaps for further research. Those developing policies and strategies targeting TRPA need to consider a range of factors at the individual, social, and environmental level to maximise the likelihood of effectiveness., (© 2022. The Author(s).)
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- 2022
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426. Sequential Deposition of Integrated Cathode-Inorganic Separator-Anode Multilayers for High Performance Li-Ion Batteries.
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Evans JD, Sun Y, and Grant PS
- Abstract
A porous, spray-deposited Al
2 O3 -based separator was developed to enable the direct deposition of an electrode/separator/electrode Li-ion battery full cell assembly in a single operation. The optimized sprayed separator consisted of 50 nm Al2 O3 particles, 1 wt % poly(acrylic acid), and 5 wt % styrene-butadiene rubber, deposited from an 80:20 vol % suspension of water and isopropanol. Separators between 5 and 22 μm thick had consistent and similar porosity of ∼58%, excellent wettability, thermal stability to at least 180 °C, adequate electrochemical stability and high effective ionic conductivity of ∼1 mS cm-1 at room temperature in an EC/DMC electrolyte, roughly double that of a conventional polypropylene separator. A sequentially deposited three-layer LiFePO4 /Al2 O3 /Li4 Ti5 O12 full cell, the first of its kind, showed similar rate performance to an identical cell with a conventional polypropylene separator, with a capacity of ∼50 mAh g-1 at 30 C. However, after cycling at 2 C for 400 cycles, Al2 O3 separator full cells retained 96.3% capacity, significantly more than conventional full cells with a capacity of 79.2% remaining.- Published
- 2022
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427. How Reproducible are Surface Areas Calculated from the BET Equation?
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Osterrieth JWM, Rampersad J, Madden D, Rampal N, Skoric L, Connolly B, Allendorf MD, Stavila V, Snider JL, Ameloot R, Marreiros J, Ania C, Azevedo D, Vilarrasa-Garcia E, Santos BF, Bu XH, Chang Z, Bunzen H, Champness NR, Griffin SL, Chen B, Lin RB, Coasne B, Cohen S, Moreton JC, Colón YJ, Chen L, Clowes R, Coudert FX, Cui Y, Hou B, D'Alessandro DM, Doheny PW, Dincă M, Sun C, Doonan C, Huxley MT, Evans JD, Falcaro P, Ricco R, Farha O, Idrees KB, Islamoglu T, Feng P, Yang H, Forgan RS, Bara D, Furukawa S, Sanchez E, Gascon J, Telalović S, Ghosh SK, Mukherjee S, Hill MR, Sadiq MM, Horcajada P, Salcedo-Abraira P, Kaneko K, Kukobat R, Kenvin J, Keskin S, Kitagawa S, Otake KI, Lively RP, DeWitt SJA, Llewellyn P, Lotsch BV, Emmerling ST, Pütz AM, Martí-Gastaldo C, Padial NM, García-Martínez J, Linares N, Maspoch D, Suárez Del Pino JA, Moghadam P, Oktavian R, Morris RE, Wheatley PS, Navarro J, Petit C, Danaci D, Rosseinsky MJ, Katsoulidis AP, Schröder M, Han X, Yang S, Serre C, Mouchaham G, Sholl DS, Thyagarajan R, Siderius D, Snurr RQ, Goncalves RB, Telfer S, Lee SJ, Ting VP, Rowlandson JL, Uemura T, Iiyuka T, van der Veen MA, Rega D, Van Speybroeck V, Rogge SMJ, Lamaire A, Walton KS, Bingel LW, Wuttke S, Andreo J, Yaghi O, Zhang B, Yavuz CT, Nguyen TS, Zamora F, Montoro C, Zhou H, Kirchon A, and Fairen-Jimenez D
- Subjects
- Adsorption, Porosity, Reproducibility of Results
- Abstract
Porosity and surface area analysis play a prominent role in modern materials science. At the heart of this sits the Brunauer-Emmett-Teller (BET) theory, which has been a remarkably successful contribution to the field of materials science. The BET method was developed in the 1930s for open surfaces but is now the most widely used metric for the estimation of surface areas of micro- and mesoporous materials. Despite its widespread use, the calculation of BET surface areas causes a spread in reported areas, resulting in reproducibility problems in both academia and industry. To prove this, for this analysis, 18 already-measured raw adsorption isotherms were provided to sixty-one labs, who were asked to calculate the corresponding BET areas. This round-robin exercise resulted in a wide range of values. Here, the reproducibility of BET area determination from identical isotherms is demonstrated to be a largely ignored issue, raising critical concerns over the reliability of reported BET areas. To solve this major issue, a new computational approach to accurately and systematically determine the BET area of nanoporous materials is developed. The software, called "BET surface identification" (BETSI), expands on the well-known Rouquerol criteria and makes an unambiguous BET area assignment possible., (© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.)
- Published
- 2022
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428. Isotope-selective pore opening in a flexible metal-organic framework.
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Bondorf L, Fiorio JL, Bon V, Zhang L, Maliuta M, Ehrling S, Senkovska I, Evans JD, Joswig JO, Kaskel S, Heine T, and Hirscher M
- Abstract
Flexible metal-organic frameworks that show reversible guest-induced phase transitions between closed and open pore phases have enormous potential for highly selective, energy-efficient gas separations. Here, we present the gate-opening process of DUT-8(Ni) that selectively responds to D
2 , whereas no response is observed for H2 and HD. In situ neutron diffraction directly reveals this pressure-dependent phase transition. Low-temperature thermal desorption spectroscopy measurements indicate an outstanding D2 -over-H2 selectivity of 11.6 at 23.3 K, with high D2 uptake. First-principles calculations coupled with statistical thermodynamics predict the isotope-selective gate opening, rationalized by pronounced nuclear quantum effects. Simulations suggest DUT-8(Ni) to remain closed in the presence of HT, while it also opens for DT and T2 , demonstrating gate opening as a highly effective approach for isotopolog separation.- Published
- 2022
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429. Cooperative light-induced breathing of soft porous crystals via azobenzene buckling.
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Krause S, Evans JD, Bon V, Crespi S, Danowski W, Browne WR, Ehrling S, Walenszus F, Wallacher D, Grimm N, Többens DM, Weiss MS, Kaskel S, and Feringa BL
- Abstract
Although light is a prominent stimulus for smart materials, the application of photoswitches as light-responsive triggers for phase transitions of porous materials remains poorly explored. Here we incorporate an azobenzene photoswitch in the backbone of a metal-organic framework producing light-induced structural contraction of the porous network in parallel to gas adsorption. Light-stimulation enables non-invasive spatiotemporal control over the mechanical properties of the framework, which ultimately leads to pore contraction and subsequent guest release via negative gas adsorption. The complex mechanism of light-gated breathing is established by a series of in situ diffraction and spectroscopic experiments, supported by quantum mechanical and molecular dynamic simulations. Unexpectedly, this study identifies a novel light-induced deformation mechanism of constrained azobenzene photoswitches relevant to the future design of light-responsive materials., (© 2022. The Author(s).)
- Published
- 2022
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430. Rituximab rescue therapy for autoimmune pulmonary alveolar proteinosis.
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Bird D, Evans J, and Pahoff C
- Abstract
Autoimmune pulmonary alveolar proteinosis (aPAP) is a rare lung disease characterised by abnormal alveolar surfactant accumulation due to macrophage dysfunction. Whole lung lavage (WLL) is the cornerstone of first-line aPAP therapy, but effective rescue treatments have not yet been well established. We report a case of a 41-year-old man with aPAP in whom further WLL is contraindicated. His diagnosis was established using a combination of classical radiological findings, positive serum GM-CSF IgG antibodies and bronchoalveolar lavage (BAL) findings. Following a literature review of emerging therapies, a decision was made to treat with a course of rituximab to suppress GM-CSF autoantibody production and restore alveolar surfactant-macrophage homeostasis. A significant clinical response was demonstrated within 6 months with improvements in arterial oxygenation, respiratory membrane gas diffusion, six-minute walk test and radiological findings., Competing Interests: None., (Crown Copyright © 2022 Published by Elsevier Ltd.)
- Published
- 2022
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431. Editorial: The Influence of Crystal Size and Morphology on Framework Materials.
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Hobday CL, Krause S, Rogge SMJ, Evans JD, and Bunzen H
- Abstract
Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
- Published
- 2022
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432. Perspectives on the Influence of Crystal Size and Morphology on the Properties of Porous Framework Materials.
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Hobday CL, Krause S, Rogge SMJ, Evans JD, and Bunzen H
- Abstract
Miniaturization is a key aspect of materials science. Owing to the increase in quality experimental and computational tools available to researchers, it has become clear that the crystal size and morphology of porous framework materials, including metal-organic frameworks and covalent organic frameworks, play a vital role in defining the physicochemical behaviour of these materials. However, given the multiscale and multidisciplinary challenges associated with establishing how crystal size and morphology affect the structure and behaviour of a material-from local to global structural modifications and from static to dynamic effects-a comprehensive mechanistic understanding of size and morphology effects is missing. Herein, we provide our perspective on the current state-of-the-art of this topic, drawn from various complementary disciplines. From a fundamental point of view, we discuss how controlling the crystal size and morphology can alter the mechanical and adsorption properties of porous framework materials and how this can impact phase stability. Special attention is also given to the quest to develop new computational tools capable of modelling these multiscale effects. From a more applied point of view, given the recent progress in this research field, we highlight the importance of crystal size and morphology control in drug delivery. Moreover, we provide an outlook on how to advance each discussed field by size and morphology control, which would open new design opportunities for functional porous framework materials., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Hobday, Krause, Rogge, Evans and Bunzen.)
- Published
- 2021
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433. Integration of Fluorescent Functionality into Pressure-Amplifying Metal-Organic Frameworks.
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Walenszus F, Evans JD, Bon V, Schwotzer F, Senkovska I, and Kaskel S
- Abstract
The flexibility of soft porous crystals, i.e., their ability to respond to external stimuli with structural changes, is one of the most fascinating features of metal-organic frameworks (MOFs). In addition to breathing and swelling phenomena of flexible MOFs, negative gas adsorption (NGA) and pressure amplification (PA) are the more recent discoveries in this field initially observed in the cubic DUT-49 framework. In recent years, the structural contraction was monitored by physisorption, X-ray diffraction, nuclear magnetic resonance (NMR), and electron paramagnetic resonance (EPR) techniques, providing only limited information about the electronic structure of the ligand. In this work, we designed a new ligand with a fluorescent core in the linker backbone and synthesized three new MOFs, isoreticular to DUT-49, denoted as DUT-140(M) (M-Cu, Co, Zn), crystallizing in the space group Fm 3̅ m . DUT-140(Cu) can be desolvated and is highly porous with an accessible apparent surface area of 4870 m
2 g-1 and a pore volume of 2.59 cm3 g-1 . Furthermore, it shows flexibility and NGA upon adsorption of subcritical gases. DUT-140(Zn), synthesized using postsynthetic metal exchange, could only be studied with guests in the pores. In addition to the investigation of the adsorption behavior of DUT-140(Cu), spectroscopic and computational methods were used to study the light absorption properties., Competing Interests: The authors declare no competing financial interest., (© 2021 American Chemical Society.)- Published
- 2021
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434. Coordination modulated on-off switching of flexibility in a metal-organic framework.
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Albalad J, Peralta RA, Huxley MT, Tsoukatos S, Shi Z, Zhang YB, Evans JD, Sumby CJ, and Doonan CJ
- Abstract
Stimuli-responsive metal-organic frameworks (MOFs) exhibit dynamic, and typically reversible, structural changes upon exposure to external stimuli. This process often induces drastic changes in their adsorption properties. Herein, we present a stimuli-responsive MOF, 1 ·[CuCl], that shows temperature dependent switching from a rigid to flexible phase. This conversion is associated with a dramatic reversible change in the gas adsorption properties, from Type-I to S-shaped isotherms. The structural transition is facilitated by a novel mechanism that involves both a change in coordination number (3 to 2) and geometry (trigonal planar to linear) of the post-synthetically added Cu(i) ion. This process serves to 'unlock' the framework rigidity imposed by metal chelation of the bis-pyrazolyl groups and realises the intrinsic flexibility of the organic link., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2021
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435. Alkyl decorated metal-organic frameworks for selective trapping of ethane from ethylene above ambient pressures.
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Schneemann A, Jing Y, Evans JD, Toyao T, Hijikata Y, Kamiya Y, Shimizu KI, Burtch NC, and Noro SI
- Abstract
The trapping of paraffins is beneficial compared to selective olefin adsorption for adsorptive olefin purification from a process engineering point of view. Here we demonstrate the use of a series of Zn2(X-bdc)2(dabco) (where X-bdc2- is bdc2- = 1,4-benzenedicarboxylate with substituting groups X, DM-bdc2- = 2,5-dimethyl-1,4-benzenedicarboxylate or TM-bdc2- = 2,3,5,6-tetramethyl-1,4-benzenedicarboxylate and dabco = diazabicyclo[2.2.2.]octane) metal-organic frameworks (MOFs) for the adsorptive removal of ethane from ethylene streams. The best performing material from this series is Zn2(TM-bdc)2(dabco) (DMOF-TM), which shows a high ethane uptake of 5.31 mmol g-1 at 110 kPa, with a good IAST selectivity of 1.88 towards ethane over ethylene. Through breakthrough measurements a high productivity of 13.1 L kg-1 per breakthrough is revealed with good reproducibility over five consecutive cycles. Molecular simulations show that the methyl groups of DMOF-TM are forming a van der Waals trap with the methylene groups from dabco, snuggly fitting the ethane. Further, rarely used high pressure coadsorption measurements, in pressure regimes that most scientific studies on hydrocarbon separation on MOFs ignore, reveal an increase in ethane capacity and selectivity for binary mixtures with increased pressures. The coadsorption measurements reveal good selectivity of 1.96 at 1000 kPa, which is verified also through IAST calculations up to 3000 kPa. This study overall showcases the opportunities that pore engineering by alkyl group incorporation and pressure increase offer to improve hydrocarbon separation in reticular materials.
- Published
- 2021
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436. Unraveling the Guest-Induced Switchability in the Metal-Organic Framework DUT-13(Zn)*.
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Felsner B, Bon V, Evans JD, Schwotzer F, Grünker R, Senkovska I, and Kaskel S
- Abstract
The switching mechanism of the flexible framework Zn
4 O(benztb)1.5 (benztb=N,N,N',N'-benzidine tetrabenzoate), also known as DUT-13, was studied by advanced powder X-ray diffraction (PXRD) and gas physisorption techniques. In situ synchrotron PXRD experiments upon physisorption of nitrogen (77 K) and n-butane (273 K) shed light on the hitherto unnoticed guest-induced breathing in the MOF. The mechanism of contraction is based on the conformationally labile benztb ligand and accompanied by a reduction in specific pore volume from 2.03 cm3 g-1 in the open-pore phase to 0.91 cm3 g-1 in the contracted-pore phase. The high temperature limit for adsorption-induced contraction of 170 K, determined by systematic temperature variation of methane adsorption isotherms, indicates that the DUT-13 framework is softer than other mesoporous MOFs like DUT-49 and does not support the formation of overloaded metastable states required for negative gas-adsorption transitions., (© 2021 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)- Published
- 2021
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437. A Universal Standard Archive File for Adsorption Data.
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Evans JD, Bon V, Senkovska I, and Kaskel S
- Abstract
New advanced adsorbents are a crucial driver for the development of energy and environmental applications. Tremendous potential is provided by machine learning and data mining techniques, as these approaches can identify the most appropriate adsorbent for a particular application. However, the current scientific reporting of adsorption isotherms in graphs and figures is not adequate to reproduce original experimentally measured data. This report proposes the specification of a new standard adsorption information file (AIF) inspired by the ubiquitous crystallographic information file (CIF) and based on the self-defining text archive and retrieval (STAR) procedure, also used to represent biological nuclear magnetic resonance experiments (NMR-STAR). The AIF is a flexible and easily extended free-format archive file that is readily human and machine readable and is simple to edit using a basic text editor or parse for database curation. This format represents the first steps toward an open adsorption data format as a basis for a decentralized adsorption data library. An open format facilitates the electronic transmission of adsorption data between laboratories, journals, and larger databases, which is key in the effort to increase open science in the field of porous materials in the future.
- Published
- 2021
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438. Charting the Complete Thermodynamic Landscape of Gas Adsorption for a Responsive Metal-Organic Framework.
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Goeminne R, Krause S, Kaskel S, Verstraelen T, and Evans JD
- Abstract
New nanoporous materials have the ability to revolutionize adsorption and separation processes. In particular, materials with adaptive cavities have high selectivity and may display previously undiscovered phenomena, such as negative gas adsorption (NGA), in which gas is released from the framework upon an increase in pressure. Although the thermodynamic driving force behind this and many other counterintuitive adsorption phenomena have been thoroughly investigated in recent years, several experimental observations remain difficult to explain. This necessitates a comprehensive analysis of gas adsorption akin to the conformational free energy landscapes used to understand the function of proteins. We have constructed the complete thermodynamic landscape of methane adsorption on DUT-49. Traversing this complex landscape reproduces the experimentally observed structural transitions, temperature dependence, and the hysteresis between adsorption and desorption. The complete thermodynamic description presented here provides unparalleled insight into adsorption and provides a framework to understand other adsorbents that challenge our preconceptions.
- Published
- 2021
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439. Materials breaking the rules: general discussion.
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Addicoat M, Bennett TD, Brammer L, Craig G, Das C, Dichtel W, Doan H, Evans AM, Evans J, Goodwin A, Horike S, Jiang J, Kaskel S, Kato M, Kitagawa S, Kobayashi A, Krause S, Lavenn C, Lee JM, Phillips AE, Roseveare TM, Schmid R, Shivanna M, Sirbu D, Tashiro S, Ting VP, van der Veen MA, Wilson B, and Zhao P
- Published
- 2021
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440. Novel computational tools: general discussion.
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Bennett TD, Brammer L, Coudert FX, Evans JD, Fischer M, Goodwin AL, Jiang J, Kaskel S, Kitagawa S, Krause S, Lee JM, Matsuda R, Rogge SMJ, Ryder MR, Schmid R, Tarzia A, van der Veen MA, and Van Speybroeck V
- Published
- 2021
- Full Text
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441. MOF matrix isolation: cooperative conformational mobility enables reliable single crystal transformations.
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Peralta RA, Huxley MT, Young RJ, Linder-Patton OM, Evans JD, Doonan CJ, and Sumby CJ
- Abstract
Obtaining structural information for highly reactive metal-based species can provide valuable insight into important chemical transformations or catalytic processes. Trapping these metal-based species within the cavities of porous crystalline hosts, such as metal-organic frameworks (MOFs), can stabilise them, allowing detailed structural elucidation by single crystal X-ray diffraction. Previously, we have used a bespoke flexible MOF, [Mn3L2L'] (MnMOF-1, where L = bis-(4-carboxyphenyl-3,5-dimethylpyrazolyl)methane and L = L', but L' has a vacant N,N'-chelation site), which has a chelating site capable of post-synthetically binding metal ions, to study organometallic transformations and fundamental isomerisation processes. This manuscript will report the underlying conformational flexibility of the framework, demonstrate the solvent dependency of post-synthetic metalation, and show that the structural flexibility of the linker site and framework are critical to controlling and achieving high levels of metal loading (and therefore site occupancy) during chemical transformations. From these results, a set of design principles for linker-based "matrix isolation" and structure determination in MOFs are derived.
- Published
- 2021
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442. The role of temperature and adsorbate on negative gas adsorption transitions of the mesoporous metal-organic framework DUT-49.
- Author
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Krause S, Evans JD, Bon V, Senkovska I, Coudert FX, Többens DM, Wallacher D, Grimm N, and Kaskel S
- Abstract
Unusual adsorption phenomena, such as breathing and negative gas adsorption (NGA), are rare and challenge our thermodynamic understanding of adsorption in deformable porous solids. In particular, NGA appears to break the rules of thermodynamics in these materials by exhibiting a spontaneous release of gas accompanying an increase in pressure. This anomaly relies on long-lived metastable states. A fundamental understanding of this process is desperately required for the discovery of new materials with this exotic property. Interestingly, NGA was initially observed upon adsorption of methane at relatively low temperature, close to the respective standard boiling point of the adsorptive, and no NGA was observed at elevated temperatures. In this contribution, we present an extensive investigation of adsorption of an array of gases at various temperatures on DUT-49, a material which features an NGA transition. Experiments, featuring a wide range of gases and vapors at temperatures ranging from 21-308 K, were used to identify for each guest a critical temperature range in which NGA can be detected. The experimental results were complemented by molecular simulations that help to rationalize the absence of NGA at elevated temperatures, and the non-monotonic behavior present upon temperature decrease. Furthermore, this in-depth analysis highlights the crucial thermodynamic and kinetic conditions for NGA, which are unique to each guest and potentially other solids with similar effects. We expect this exploration to provide detailed guidelines for experimentally discovering NGA and related "rule breaking" phenomena in novel and already known materials, and provide the conditions required for the application of this effect, for example as pressure amplifying materials.
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- 2021
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443. Advanced characterisation techniques: multi-scale, in situ , and time-resolved: general discussion.
- Author
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Brammer L, Burrows AD, Chong SY, Craig G, Evans J, Farha O, Farrusseng D, Fischer M, Goodwin A, Huang Z, Johnson B, Kaskel S, Kitagawa S, Lavenn C, Lee AY, Lee JM, Matsuda R, Phillips AE, Rainer DN, Ryder MR, Schmid R, Shivanna M, Sumby C, Taddei M, Terry L, Ting VP, van der Veen MA, and West NG
- Published
- 2021
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444. Cooperative and synchronized rotation in motorized porous frameworks: impact on local and global transport properties of confined fluids.
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Evans JD, Krause S, and Feringa BL
- Abstract
Molecules in gas and liquid states, as well as in solution, exhibit significant and random Brownian motion. Molecules in the solid-state, although strongly immobilized, can still exhibit significant intramolecular dynamics. However, in most framework materials, these intramolecular dynamics are driven by temperature, and therefore are neither controlled nor spatially or temporarily aligned. In recent years, several examples of molecular machines that allow for a stimuli-responsive control of dynamical motion, such as rotation, have been reported. In this contribution, we investigate the local and global properties of a Lennard-Jones (LJ) fluid surrounding a molecular motor and consider the influence of cooperative and non-directional rotation for a molecular motor-containing pore system. This study uses classical molecular dynamics simulations to describe a minimal model, which was developed to resemble known molecular motors. The properties of an LJ liquid surrounding an isolated molecular motor remain mostly unaffected by the introduced rotation. We then considered an arrangement of motors within a one-dimensional pore. Changes in diffusivity for pore sizes approaching the length of the rotor were observed, resulting from rotation of the motors. We also considered the influence of cooperative motor directionality on the directional transport properties of this confined fluid. Importantly, we discovered that specific unidirectional rotation of altitudinal motors can produce directed diffusion. This study provides an essential insight into molecular machine-containing frameworks, highlighting the specific structural arrangements that can produce directional mass transport.
- Published
- 2021
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445. Molecular Diffusion in a Flexible Mesoporous Metal-Organic Framework over the Course of Structural Contraction.
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Walenszus F, Bon V, Evans JD, Kaskel S, and Dvoyashkin M
- Abstract
In situ
1 H pulsed field gradient (PFG) NMR was used to investigate the molecular diffusion of n -butane in the pores of the flexible metal-organic framework DUT-49(Cu) at 298 K at different pore loadings, including pressure ranges below and above the negative gas adsorption (NGA) transition caused by structural contraction of the material. Supported by molecular dynamics simulations, the investigation provided crucial insight into confined diffusion within a highly flexible pore environment. The self-diffusion coefficients were derived from the experiment and compared with simulations, capturing the diffusion during n -butane adsorption and desorption. This complementary approach has yielded experimental characterization of molecular diffusion mechanisms during the unique process of NGA. This includes the observation of a 4-fold decrease of diffusivity within a less than 2 kPa gas pressure variation, corresponding to the NGA transition point.- Published
- 2020
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446. Engineering micromechanics of soft porous crystals for negative gas adsorption.
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Krause S, Evans JD, Bon V, Senkovska I, Ehrling S, Iacomi P, Többens DM, Wallacher D, Weiss MS, Zheng B, Yot PG, Maurin G, Llewellyn PL, Coudert FX, and Kaskel S
- Abstract
Framework materials at the molecular level, such as metal-organic frameworks (MOF), were recently found to exhibit exotic and counterintuitive micromechanical properties. Stimulated by host-guest interactions, these so-called soft porous crystals can display counterintuitive adsorption phenomena such as negative gas adsorption (NGA). NGA materials are bistable frameworks where the occurrence of a metastable overloaded state leads to pressure amplification upon a sudden framework contraction. How can we control activation barriers and energetics via functionalization of the molecular building blocks that dictate the frameworks' mechanical response? In this work we tune the elastic and inelastic properties of building blocks at the molecular level and analyze the mechanical response of the resulting frameworks. From a set of 11 frameworks, we demonstrate that widening of the backbone increases stiffness, while elongation of the building blocks results in a decrease in critical yield stress of buckling. We further functionalize the backbone by incorporation of sp
3 hybridized carbon atoms to soften the molecular building blocks, or stiffen them with sp2 and sp carbons. Computational modeling shows how these modifications of the building blocks tune the activation barriers within the energy landscape of the guest-free bistable frameworks. Only frameworks with free energy barriers in the range of 800 to 1100 kJ mol-1 per unit cell, and moderate yield stress of 0.6 to 1.2 nN for single ligand buckling, exhibit adsorption-induced contraction and negative gas adsorption. Advanced experimental in situ methodologies give detailed insights into the structural transitions and the adsorption behavior. The new framework DUT-160 shows the highest magnitude of NGA ever observed for nitrogen adsorption at 77 K. Our computational and experimental analysis of the energetics and mechanical response functions of porous frameworks is an important step towards tuning activation barriers in dynamic framework materials and provides critical design principles for molecular building blocks leading to pressure amplifying materials., Competing Interests: The authors have no conflict of interest to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2020
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447. Highly Active Gas Phase Organometallic Catalysis Supported Within Metal-Organic Framework Pores.
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Peralta RA, Huxley MT, Evans JD, Fallon T, Cao H, He M, Zhao XS, Agnoli S, Sumby CJ, and Doonan CJ
- Abstract
Metal-organic frameworks (MOFs) can act as a platform for the heterogenization of molecular catalysts, providing improved stability, allowing easy catalyst recovery and a route toward structural elucidation of the active catalyst. We have developed a MOF, 1 , possessing vacant N , N -chelating sites which are accessible via the porous channels that penetrate the structure. In the present work, cationic rhodium(I) norbornadiene (NBD) and bis(ethylene) (ETH) complexes paired with both noncoordinating and coordinating anions have been incorporated into the N , N -chelation sites of 1 via postsynthetic metalation and facile anion exchange. Exploiting the crystallinity of the host framework, the immobilized Rh(I) complexes were structurally characterized using X-ray crystallography. Ethylene hydrogenation catalysis by 1 ·[Rh(NBD)]X and 1 ·[Rh(ETH)
2 ]X (X = Cl and BF4 ) was studied in the gas phase (2 bar, 46 °C) to reveal that 1 ·[Rh(ETH)2 ](BF4 ) was the most active catalyst (TOF = 64 h-1 ); the NBD materials and the chloride salt were notably less active. On the basis of these observations, the activity of the Rh(I) bis(ethylene) complexes, 1 ·[Rh(ETH)2 ]BF4 and 1 ·[Rh(ETH)2 ]Cl, in butene isomerization was also studied using gas-phase NMR spectroscopy. Under one bar of butene at 46 °C, 1 ·[Rh(ETH)2 ]BF4 rapidly catalyzes the conversion of 1-butene to 2-butene with a TOF averaging 2000 h-1 over five cycles. Notably, the chloride derivative, 1 [Rh(ETH)2 ]Cl displays negligible activity in comparison. XPS analysis of the postcatalysis sample, supported by DFT calculations, suggest that the catalytic activity is inhibited by the strong interactions between a Rh(III) allyl hydride intermediate and the chloride anion.- Published
- 2020
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448. The American Board of Orthopaedic Surgery Response to COVID-19.
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Wright RW, Armstrong AD, Azar FM, Bednar MS, Carpenter JE, Evans JB, Flynn JM, Garvin KL, Jacobs JJ, Kang JD, Lundy DW, Mencio GA, Murray PM, Nelson CL, Peabody T, Porter SE, Roberson JR, Saltzman CL, Sebastianelli WJ, Taitsman LA, Van Heest AE, and Martin DF
- Subjects
- COVID-19, Clinical Competence standards, Education, Medical, Continuing standards, Education, Medical, Graduate standards, Female, Humans, Male, Pandemics statistics & numerical data, Safety Management, Specialty Boards standards, United States, Communicable Disease Control methods, Coronavirus Infections, Occupational Health, Orthopedic Procedures education, Pandemics prevention & control, Patient Safety, Pneumonia, Viral
- Abstract
The COVID-19 pandemic has disrupted every aspect of society in a way never previously experienced by our nation's orthopaedic surgeons. In response to the challenges the American Board of Orthopaedic Surgery has taken steps to adapt our Board Certification and Continuous Certification processes. These changes were made to provide flexibility for as many Candidates and Diplomates as possible to participate while maintaining our high standards. The American Board of Orthopaedic Surgery is first and foremost committed to the safety and well-being of our patients, physicians, and families while striving to remain responsive to the changing circumstances affecting our Candidates and Diplomates.
- Published
- 2020
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449. Four-dimensional metal-organic frameworks.
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Evans JD, Bon V, Senkovska I, Lee HC, and Kaskel S
- Abstract
Recognising timescale as an adjustable dimension in porous solids provides a new perspective to develop novel four-dimensional framework materials. The deliberate design of three-dimensional porous framework architectures is a developed field; however, the understanding of dynamics in open frameworks leaves a number of key questions unanswered: What factors determine the spatiotemporal evolution of deformable networks? Can we deliberately engineer the response of dynamic materials along a time-axis? How can we engineer energy barriers for the selective recognition of molecules? Answering these questions will require significant methodological development to understand structural dynamics across a range of time and length scales.
- Published
- 2020
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450. Direct Mechanocatalysis: Palladium as Milling Media and Catalyst in the Mechanochemical Suzuki Polymerization.
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Vogt CG, Grätz S, Lukin S, Halasz I, Etter M, Evans JD, and Borchardt L
- Abstract
The milling ball is the catalyst. We introduce a palladium-catalyzed reaction inside a ball mill, which makes catalyst powders, ligands, and solvents obsolete. We present a facile and highly sustainable synthesis concept for palladium-catalyzed C-C coupling reactions, exemplarily showcased for the Suzuki polymerization of 4-bromo or 4-iodophenylboronic acid giving poly(para-phenylene). Surprisingly, we observe one of the highest degrees of polymerization (199) reported so far., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)
- Published
- 2019
- Full Text
- View/download PDF
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