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1.
BMC Med Educ ; 15: 76, 2015 Apr 14.
Article in English | MEDLINE | ID: mdl-25889758

ABSTRACT

BACKGROUND: We aimed to explore the influence of a motivationally-enhanced instructional design on motivation to learn and knowledge, hypothesizing that outcomes would be higher for the enhanced instructional format. METHODS: Medicine residents completed four online learning modules on primary care topics. Using a crossover design, learners were randomized to receive two standard and two motivationally-enhanced learning modules. Both formats had self-assessment questions, but the enhanced format questions were framed to place learners in a supervisory/teaching role. Learners received a baseline motivation questionnaire, a short motivation survey before and after each module, and a knowledge posttest. RESULTS: One hundred twenty seven residents were randomized. 123 residents (97%) completed at least one knowledge posttest and 119 (94%) completed all four posttests. Across all modules, a one-point increase in the pretest short motivation survey was associated with a 2.1-point increase in posttest knowledge. The change in motivation was significantly higher for the motivationally enhanced format (standard mean change -0.01, enhanced mean change +0.09, difference = 0.10, CI 0.001 to 0.19; p = 0.048). Mean posttest knowledge score was similar (standard mean 72.8, enhanced mean 73.0, difference = 0.2, CI -1.9 to 2.1; p = 0.90). CONCLUSIONS: The motivationally enhanced instructional format improved motivation more than the standard format, but impact on knowledge scores was small and not statistically significant. Learners with higher pre-intervention motivation scored better on post-intervention knowledge tests, suggesting that motivation may prove a viable target for future instructional enhancements.


Subject(s)
Computer-Assisted Instruction/methods , Internship and Residency , Motivation , Students, Medical/psychology , Cross-Over Studies , Family Practice/education , Humans , Internal Medicine/education , Self-Assessment , Surveys and Questionnaires
2.
Lancet ; 392(10160): 2167, 2018 11 17.
Article in English | MEDLINE | ID: mdl-30496097
3.
BMC Med Educ ; 14: 128, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-24985690

ABSTRACT

BACKGROUND: Some evidence suggests that attitude toward computer-based instruction is an important determinant of success in online learning. We sought to determine how comfort using computers and perceptions of prior online learning experiences have changed over the past decade, and how these associate with learning outcomes. METHODS: Each year from 2003-2011 we conducted a prospective trial of online learning. As part of each year's study, we asked medicine residents about their comfort using computers and if their previous experiences with online learning were favorable. We assessed knowledge using a multiple-choice test. We used regression to analyze associations and changes over time. RESULTS: 371 internal medicine and family medicine residents participated. Neither comfort with computers nor perceptions of prior online learning experiences showed a significant change across years (p > 0.61), with mean comfort rating 3.96 (maximum 5 = very comfortable) and mean experience rating 4.42 (maximum 6 = strongly agree [favorable]). Comfort showed no significant association with knowledge scores (p = 0.39) but perceptions of prior experiences did, with a 1.56% rise in knowledge score for a 1-point rise in experience score (p = 0.02). Correlations among comfort, perceptions of prior experiences, and number of prior experiences were all small and not statistically significant. CONCLUSIONS: Comfort with computers and perceptions of prior experience with online learning remained stable over nine years. Prior good experiences (but not comfort with computers) demonstrated a modest association with knowledge outcomes, suggesting that prior course satisfaction may influence subsequent learning.


Subject(s)
Computer-Assisted Instruction , Attitude to Computers , Computer-Assisted Instruction/methods , Educational Measurement , Family Practice/education , Humans , Internal Medicine/education , Internship and Residency/methods
4.
bioRxiv ; 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38746241

ABSTRACT

The Zika virus (ZIKV), discovered in Africa in 1947, swiftly spread across continents, causing significant concern due to its recent association with microcephaly in newborns and Guillain-Barré syndrome in adults. Despite a decrease in prevalence, the potential for a resurgence remains, necessitating urgent therapeutic interventions. Like other flaviviruses, ZIKV presents promising drug targets within its replication machinery, notably the NS3 helicase (NS3Hel) protein, which plays critical roles in viral replication. However, a lack of structural information impedes the development of specific inhibitors targeting NS3Hel. Here we applied high-throughput crystallographic fragment screening on ZIKV NS3Hel, which yielded structures that reveal 3D binding poses of 46 fragments at multiple sites of the protein, including 11 unique fragments in the RNA-cleft site. These fragment structures provide templates for direct design of hit compounds and should thus assist the development of novel direct-acting antivirals against ZIKV and related flaviviruses, thus opening a promising avenue for combating future outbreaks.

5.
bioRxiv ; 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38746305

ABSTRACT

Zika virus (ZIKV) infections cause microcephaly in new-borns and Guillain-Barre syndrome in adults raising a significant global public health concern, yet no vaccines or antiviral drugs have been developed to prevent or treat ZIKV infections. The viral protease NS3 and its co-factor NS2B are essential for the cleavage of the Zika polyprotein precursor into individual structural and non-structural proteins and is therefore an attractive drug target. Generation of a robust crystal system of co-expressed NS2B-NS3 protease has enabled us to perform a crystallographic fragment screening campaign with 1076 fragments. 48 binders with diverse chemical scaffolds were identified in the active site of the protease, with another 6 fragment hits observed in a potential allosteric binding site. Our work provides potential starting points for the development of potent NS2B-NS3 protease inhibitors. Furthermore, we have structurally characterized a potential allosteric binding pocket, identifying opportunities for allosteric inhibitor development.

6.
bioRxiv ; 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38746446

ABSTRACT

Enteroviruses are the causative agents of paediatric hand-foot-and-mouth disease, and a target for pandemic preparedness due to the risk of higher order complications in a large-scale outbreak. The 2A protease of these viruses is responsible for the self-cleavage of the poly protein, allowing for correct folding and assembly of capsid proteins in the final stages of viral replication. These 2A proteases are highly conserved between Enterovirus species, such as Enterovirus A71 and Coxsackievirus A16 . Inhibition of the 2A protease deranges capsid folding and assembly, preventing formation of mature virions in host cells and making the protease a valuable target for antiviral activity. Herein, we describe a crystallographic fragment screening campaign that identified 75 fragments which bind to the 2A protease including 38 unique compounds shown to bind within the active site. These fragments reveal a path for the development of non-peptidomimetic inhibitors of the 2A protease with broad-spectrum anti-enteroviral activity.

7.
J Phys Chem A ; 117(39): 9380-90, 2013 Oct 03.
Article in English | MEDLINE | ID: mdl-23215001

ABSTRACT

When a Ne/O2 mixture is codeposited at 4.3 K with a Ne/H2 mixture that has been passed through a microwave discharge, the infrared spectrum of the resulting deposit includes prominent absorptions of the three vibrational fundamentals of HO2 and seven relatively weak absorptions in the infrared and near-infrared, only one of them previously reported, that can be assigned to overtones and combination bands of that product. Similar assignments are made for DO2. A new, broad absorption at 702.9 cm(-1) appears close to the gas-phase absorption of HOHOH(-) at 697 cm(-1). Isotopic substitution experiments support that assignment. Evidence is also presented for the stabilization of HOHO(-). Absorptions near the vibrational fundamentals of H2O and an absorption at 3472.4 cm(-1) grow on exposure of the deposit to radiation of wavelength shorter than 345 nm. These absorptions are assigned to the H2O(HO) complex, in agreement with the results of an earlier argon-matrix study. In both studies, photodestruction of HO2 molecules that have H2O trapped in a nearby site results in formation of the complex. Because the discharge through Ne/H2 supports ion production, photodetachment of the resulting HOHOH(-) is an additional source of the complex. Other absorptions may be contributed by the bending fundamental of HO2(+) and by a cation complex with H2.

8.
J Phys Chem A ; 117(50): 13443-9, 2013 Dec 19.
Article in English | MEDLINE | ID: mdl-23944709

ABSTRACT

Recently, gas-phase absorptions in the 3000-4300 cm(-1) spectral region have been assigned to combination bands built on (ν1 + ν5) of ground-state cyc-O4(+). Other gas-phase experiments identified an electronic transition of cyc-O4(-) complexed with an argon atom between 4000 and 5300 cm(-1). Absorptions that correspond closely to these two groups of bands have been observed in neon-matrix experiments in which both cyc-O4(+) and cyc-O4(-) are trapped at 4.3 K in solid neon. The results are compared with the gas-phase data, and the proposed assignments are considered by taking into account the results of isotopic substitution.

10.
RSC Sustain ; 1(3): 494-503, 2023 May 11.
Article in English | MEDLINE | ID: mdl-37215582

ABSTRACT

Metal-Organic Framework (MOF)-derived TiO2, synthesised through the calcination of MIL-125-NH2, is investigated for its potential as a CO2 photoreduction catalyst. The effect of the reaction parameters: irradiance, temperature and partial pressure of water was investigated. Using a two-level design of experiments, we were able to evaluate the influence of each parameter and their potential interactions on the reaction products, specifically the production of CO and CH4. It was found that, for the explored range, the only statistically significant parameter is temperature, with an increase in temperature being correlated to enhanced production of both CO and CH4. Over the range of experimental settings explored, the MOF-derived TiO2 displays high selectivity towards CO (98%), with only a small amount of CH4 (2%) being produced. This is notable when compared to other state-of-the-art TiO2 based CO2 photoreduction catalysts, which often showcase lower selectivity. The MOF-derived TiO2 was found to have a peak production rate of 8.9 × 10-4 µmol cm-2 h-1 (2.6 µmol g-1 h-1) and 2.6 × 10-5 µmol cm-2 h-1 (0.10 µmol g-1 h-1) for CO and CH4, respectively. A comparison is made to commercial TiO2, P25 (Degussa), which was shown to have a similar activity towards CO production, 3.4 × 10-3 µmol cm-2 h-1 (5.9 µmol g-1 h-1), but a lower selectivity preference for CO (3 : 1 CH4 : CO) than the MOF-derived TiO2 material developed here. This paper showcases the potential for MIL-125-NH2 derived TiO2 to be further developed as a highly selective CO2 photoreduction catalyst for CO production.

11.
J Chem Phys ; 137(14): 144305, 2012 Oct 14.
Article in English | MEDLINE | ID: mdl-23061846

ABSTRACT

When a Ne:H(2)O(2) mixture is codeposited at 4.3 K with a beam of neon atoms that have been excited in a microwave discharge, three new, photosensitive absorptions appear which can be assigned to the three infrared-active vibrational fundamentals of trans-HOOH(+). When the Ne:H(2)O(2) deposition system is pretreated with the vapors of D(2)O, the product absorptions include new peaks which can be attributed to vibrational fundamentals of trans-HOOD(+) and trans-DOOD(+). Density functional calculations of the vibrational fundamentals of the three hydrogen peroxide cation isotopologues support the proposed assignments. Broad, photosensitive product absorptions also appear near the positions of vibrational transitions of O(3)(-), and may be contributed by a weakly bound complex of that species with H(2)O.

12.
J Chem Phys ; 134(19): 194306, 2011 May 21.
Article in English | MEDLINE | ID: mdl-21599058

ABSTRACT

Observations on a Ne:BF(3) = 400:1 mixture into which a trace of normal or isotopically enriched water had been introduced, codeposited at 4.3 K with a beam of neon atoms that had been excited in a microwave discharge, demonstrate that a pair of absorptions at 1662 cm(-1) and 1722 cm(-1) that were previously assigned to the two boron-isotopic species of BF(3)(+) should be reassigned to a BF(2) stretching fundamental of BF(2)OH(+). The OH stretching fundamental of that product was identified for the first time at 3240 cm(-1). The degenerate BF(3) stretching fundamental of (11)BF(3)(+) appears at an unusually high frequency, 1790 cm(-1), consistent with strong pseudo-Jahn-Teller interaction of that ground-state fundamental with the B̃(2)E(') electronic state, as predicted by theory. The recent availability of detailed ab initio and density functional calculations of the vibrational fundamentals of BF(2)(-) and BF(3)(-) facilitates assignment of the infrared absorptions of those two products.

13.
J Chem Phys ; 134(6): 064321, 2011 Feb 14.
Article in English | MEDLINE | ID: mdl-21322694

ABSTRACT

When a mixture of ethylene in a large excess of neon is codeposited at 4.3 K with a beam of neon atoms that have been excited in a microwave discharge, two groups of product absorptions appear in the infrared spectrum of the deposit. Similar studies using C(2)H(4)-1-(13)C and C(2)D(4) aid in product identification. The first group of absorptions arises from a cation product which possesses two identical carbon atoms, giving the first infrared identification of two fundamentals of C(2)H(4)(+) and three of C(2)D(4)(+), as well as a tentative identification of ν(9) of C(2)H(4)(+). The positions of these absorptions are consistent with the results of density functional calculations and of earlier photoelectron studies. All of the members of the second group of product absorptions possess two inequivalent carbon atoms. They are assigned to the vinyl radical, C(2)H(3), and to C(2)D(3), in agreement with other recent infrared assignments for those species.

14.
J Chem Phys ; 135(22): 224307, 2011 Dec 14.
Article in English | MEDLINE | ID: mdl-22168694

ABSTRACT

Codeposition of a Ne:N(2):CO = 200:1:1 mixture at 4.3 K with a beam of very pure neon atoms excited to their energy levels between 16.6 and 16.85 eV leads to stabilization in the resulting solid of sufficient NNCO(+) for detection of its NN- and CO-stretching vibration fundamentals. Detailed isotopic substitution studies and density functional calculations for the various isotopologues support the identification of NNCO(+) and permit estimation of the positions of two of its low-frequency fundamentals. A sufficient concentration of NOCN is also stabilized in the neon matrix for detection of its NO-stretching vibrational fundamental.

15.
Med Educ ; 45(12): 1230-40, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22026751

ABSTRACT

CONTEXT: The Motivated Strategies for Learning Questionnaire (MSLQ) purports to measure motivation using the expectancy-value model. Although it is widely used in other fields, this instrument has received little study in health professions education. OBJECTIVES: The purpose of this study was to evaluate the validity of MSLQ scores. METHODS: We conducted a validity study evaluating the relationships of MSLQ scores to other variables and their internal structure (reliability and factor analysis). Participants included 210 internal medicine and family medicine residents participating in a web-based course on ambulatory medicine at an academic medical centre. Measurements included pre-course MSLQ scores, pre- and post-module motivation surveys, post-module knowledge test and post-module Instructional Materials Motivation Survey (IMMS) scores. RESULTS: Internal consistency was universally high for all MSLQ items together (Cronbach's α = 0.93) and for each domain (α ≥ 0.67). Total MSLQ scores showed statistically significant positive associations with post-test knowledge scores. For example, a 1-point rise in total MSLQ score was associated with a 4.4% increase in post-test scores (ß = 4.4; p < 0.0001). Total MSLQ scores showed moderately strong, statistically significant associations with several other measures of effort, motivation and satisfaction. Scores on MSLQ domains demonstrated associations that generally aligned with our hypotheses. Self-efficacy and control of learning belief scores demonstrated the strongest domain-specific relationships with knowledge scores (ß = 2.9 for both). Confirmatory factor analysis showed a borderline model fit. Follow-up exploratory factor analysis revealed the scores of five factors (self-efficacy, intrinsic interest, test anxiety, extrinsic goals, attribution) demonstrated psychometric and predictive properties similar to those of the original scales. CONCLUSIONS: Scores on the MSLQ are reliable and predict meaningful outcomes. However, the factor structure suggests a simplified model might better fit the empiric data. Future research might consider how assessing and responding to motivation could enhance learning.


Subject(s)
Internship and Residency/statistics & numerical data , Motivation , Probability Learning , Psychometrics/standards , Students, Medical/psychology , Education, Medical , Female , Humans , Knowledge , Learning , Male , Personal Satisfaction , Psychometrics/methods , Reproducibility of Results , Surveys and Questionnaires
16.
AAOHN J ; 59(9): 377-86, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21877670

ABSTRACT

Hospital nurses who are working mothers are challenged to maintain their personal health and model healthy behaviors for their children. This study aimed to develop and test an innovative 10-week worksite physical activity intervention integrated into the work flow of hospital-based nurses who were mothers. Three volunteer adult medical-surgical nursing units participated as intervention units. Fifty-eight nurses (30 intervention and 28 control) provided baseline and post-intervention repeated measurements of physical activity (steps) and body composition. Intervention participants provided post-intervention focus group feedback. For both groups, daily steps averaged more than 12,400 at baseline and post-intervention. No significant effects were found for physical activity; significant effects were found for fat mass, fat index, and percent fat (p < .03). Focus group findings supported the intervention and other data collected. The worksite holds promise for targeting the health of working mothers. Future research is warranted with a larger sample, longer intervention, and additional measures.


Subject(s)
Exercise , Health Promotion , Mothers , Nursing Staff, Hospital , Adiposity , Adult , Body Mass Index , Feasibility Studies , Female , Humans , Linear Models , Middle Aged , Pilot Projects , United States
17.
Transl Behav Med ; 11(8): 1596-1605, 2021 08 13.
Article in English | MEDLINE | ID: mdl-33837786

ABSTRACT

Innovative methodological frameworks are needed in intervention science to increase efficiency, potency, and community adoption of behavioral health interventions, as it currently takes 17 years and millions of dollars to test and disseminate interventions. The multiphase optimization strategy (MOST) for developing behavioral interventions was designed to optimize efficiency, efficacy, and sustainability, while community-based participatory research (CBPR) engages community members in all research steps. Classical approaches for developing behavioral interventions include testing against control interventions in randomized controlled trials. MOST adds an optimization phase to assess performance of individual intervention components and their interactions on outcomes. This information is used to engineer interventions that meet specific optimization criteria focused on effectiveness, cost, or time. Combining CBPR and MOST facilitates development of behavioral interventions that effectively address complex health challenges, are acceptable to communities, and sustainable by maximizing resources, building community capacity and acceptance. Herein, we present a case study to illustrate the value of combining MOST and CBPR to optimize a multilevel intervention for reducing substance misuse among formerly incarcerated men, for under $250 per person. This integration merged experiential and cutting-edge scientific knowledge and methods, built community capacity, and promoted the development of efficient interventions. Integrating CBPR and MOST principles yielded a framework of intervention development/testing that is more efficient, faster, cheaper, and rigorous than traditional stage models. Combining MOST and CBPR addressed significant intervention science gaps and speeds up testing and implementation of interventions.


Subject(s)
Behavioral Sciences , Community-Based Participatory Research , Behavior Therapy , Humans , Male
18.
J Phys Chem A ; 114(14): 4712-8, 2010 Apr 15.
Article in English | MEDLINE | ID: mdl-19957977

ABSTRACT

NO(3) has been stabilized in a neon matrix at 4.3 K in sufficient yield for detection of the absorptions between 7000 and 10,000 cm(-1), which arise from vibronically allowed transitions from the ground state to levels of the A (2)E'' state. The results confirm and somewhat extend previous gas-phase observations for (14)N(16)O(3). Additional spectra are presented for six other isotopologues of NO(3), four of which possess C(2v) symmetry. The splitting patterns for these species support the previous assignments. Alternations in the spacings of the nu(4) progression are consistent with the occurrence of weak to moderate Jahn-Teller interaction in the A 2E state of NO(3).

19.
RSC Adv ; 10(47): 27989-27994, 2020 Jul 27.
Article in English | MEDLINE | ID: mdl-35519115

ABSTRACT

To improve the CO2 adsorption on the photocatalyst, which is an essential step for CO2 photoreduction, solid solutions were fabricated using a facile calcination treatment at 900 °C. Using various alkalis, namely NaOH, Na2CO3, KOH, K2CO3, the resulted samples presented a much higher CO2 adsorption capacity, which was measured with the pulse injection of CO2 on the temperature programmed desorption workstation, compared to the pristine Evonik P25. As a result, all of the fabricated solid solutions produced higer yield of CO under UV light irradiation due to the increased basicity of the solid solutions even though they possessed only the rutile polymorph of TiO2. The highest CO2 adsorption capacity under UV irradiation was observed in the sample treated with NaOH, which contained the highest amount of isolated hydroxyls, as shown in the FTIR studies.

20.
Chem Commun (Camb) ; 56(81): 12150-12153, 2020 Oct 13.
Article in English | MEDLINE | ID: mdl-32909021

ABSTRACT

TiO2-x/W18O49 with core-shell or double-shelled hollow microspheres were synthesized through a facile multi-step solvothermal method. The formation of the hollow microspheres with a double-shell was a result of the Kirkendall effect during the solvothermal treatment with concentrated NaOH. The advanced architecture significantly enhanced the electronic properties of TiO2-x/W18O49, improving by more than 30 times the CO2 photoreduction efficiency compared to the pristine W18O49. Operando DRIFTS measurements revealed that the yellow TiO2-x was a preferable CO2 adsorption and conversion site.

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