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1.
Chem Sci ; 15(29): 11391-11401, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39055005

ABSTRACT

This work investigates and describes the structural dynamics taking place following charge-transfer-to-solvent photo-abstraction of electrons from I- and Br- ions in aqueous solution following single- and 2-photon excitation at 202 nm and 400 nm, respectively. A Time-Resolved X-ray Solution Scattering (TR-XSS) approach with direct sensitivity to the structure of the surrounding solvent as the water molecules adopt a new equilibrium configuration following the electron-abstraction process is utilized to investigate the structural dynamics of solvent shell expansion and restructuring in real-time. The structural sensitivity of the scattering data enables a quantitative evaluation of competing models for the interaction between the nascent neutral species and surrounding water molecules. Taking the I0-O distance as the reaction coordinate, we find that the structural reorganization is delayed by 0.1 ps with respect to the photoexcitation and completes on a time scale of 0.5-1 ps. On longer time scales we determine from the evolution of the TR-XSS difference signal that I0: e- recombination takes place on two distinct time scales of ∼20 ps and 100 s of picoseconds. These dynamics are well captured by a simple model of diffusive evolution of the initial photo-abstracted electron population where the charge-transfer-to-solvent process gives rise to a broad distribution of electron ejection distances, a significant fraction of which are in the close vicinity of the nascent halogen atoms and recombine on short time scales.

3.
Afr J Prim Health Care Fam Med ; 16(1): e1-e4, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38708732

ABSTRACT

Family physicians require leadership skills to strengthen team-based primary care services. Interviews with South African district managers confirmed the need to develop leadership skills in family physicians. The updated national programmatic learning outcomes for South African family physician training were published in 2021. They sparked the need for curriculum renewal at the University of Cape Town's Division of Family Medicine. A review of the leadership and governance module during registrar training showed that the sessions were perceived to be content heavy with insufficient opportunities for reflection. Following a series of stakeholder engagements, the module convenors co-designed a revised module that was blueprinted on the updated learning outcomes. The module incorporates a group coaching style, facilitating learning through reflection on one's experiences. The revised module was implemented in 2022. It aims to provide a transformative learning experience centred on students' perceptions of themselves as leaders, as well as professional identity formation and resilience building. This short report describes preliminary insights from the revised module's developmental phase and forms part of an ongoing iterative evaluation process.Contribution: Family physicians should lead across all their defined roles. Formal and informal learning opportunities are needed to facilitate their growth as leaders and help them to meet the health needs of communities served by an evolving health care system. This short report describes an example of a revised postgraduate module on leadership and governance, which may be of value to clinician educators and academic departments exploring innovative methods for the African region.


Subject(s)
Curriculum , Leadership , Primary Health Care , Humans , South Africa , Family Practice/education , Physicians, Family/education
5.
N Biotechnol ; 82: 92-106, 2024 Sep 25.
Article in English | MEDLINE | ID: mdl-38788897

ABSTRACT

Species of Saccharomyces genus have played an irreplaceable role in alcoholic beverage and baking industry for centuries. S. cerevisiae has also become an organism of choice for industrial production of alcohol and other valuable chemicals and a model organism shaping the rise of modern genetics and genomics in the past few decades. Today´s brewing industry faces challenges of decreasing consumption of traditional beer styles and increasing consumer demand for new styles, flavors and aromas. The number of currently used brewer's strains and their genetic diversity is yet limited and implementation of more genetic and phenotypic variation is seen as a solution to cope with the market challenges. This requires modification of current production strains or introduction of novel strains from other settings, e.g. industrial or wild habitats into the brewing industry. Due to legal regulation in many countries and negative customer perception of GMO organisms, the production of food and beverages requires non-GMO production organisms, whose development can be difficult and time-consuming. Here, we apply FIND-IT (Fast Identification of Nucleotide variants by DigITal PCR), an ultrafast genome-mining method, for isolation of novel yeast variants with varying flavor profiles. The FIND-IT method uses combination of random mutagenesis, droplet digital PCR with probes that target a specific desired mutation and a sub-isolation of the mutant clone. Such an approach allows the targeted identification and isolation of specific mutant strains with eliminated production of certain flavor and off-flavors and/or changes in the strain metabolism. We demonstrate that the technology is useful for the identification of loss-of function or gain of function mutations in unrelated industrial and wild strains differing in ploidy. Where no other phenotypic selection exists, this technology serves together with standard breeding techniques as a modern tool facilitating a modification of (brewer's) yeast strains leading to diversification of the product portfolio.


Subject(s)
Beer , Metabolic Engineering , Saccharomyces , Beer/microbiology , Saccharomyces/genetics , Saccharomyces/metabolism , Flavoring Agents/metabolism , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/genetics
6.
Respir Investig ; 62(4): 589-596, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38692040

ABSTRACT

BACKGROUND: In previous Japanese subgroup/subset analyses of the global INBUILD trial, nintedanib reduced the annual rate of forced vital capacity (FVC) decline and the risk of disease progression in patients with progressive fibrosing interstitial lung diseases (PF-ILDs). This exploratory subset analysis assessed the effect of nintedanib on symptoms and impacts of pulmonary fibrosis in Japanese patients with PF-ILDs, including those with usual interstitial pneumonia (UIP)-like fibrotic pattern on high-resolution computed tomography (HRCT). METHODS: This analysis included Japanese patients who received at least one dose of study treatment in the randomized, double-blind, placebo-controlled INBUILD trial. The Living with Pulmonary Fibrosis (L-PF) questionnaire was used to assess pulmonary fibrosis symptoms and impacts (higher scores indicated greater impairment) at baseline and weeks 12-52. RESULTS: In total, 108 Japanese patients (nintedanib: n = 52; placebo: n = 56) were included; 84 patients had UIP-like fibrotic pattern on HRCT. In the total Japanese subgroup and in those with UIP-like fibrotic pattern, numerically greater increases in L-PF total, symptoms total, symptoms fatigue domain, and impacts scores were observed in the placebo group than in the nintedanib group at all timepoints, starting from week 12. A numerically greater increase in the symptoms dyspnea domain score was observed with placebo versus nintedanib starting from week 36. Throughout the study, the symptoms cough domain score increased in the placebo group but decreased in the nintedanib group. CONCLUSIONS: Our findings demonstrate that nintedanib has the potential to reduce the worsening of symptoms and impacts of pulmonary fibrosis in Japanese patients with PF-ILDs.


Subject(s)
Disease Progression , Indoles , Lung Diseases, Interstitial , Quality of Life , Indoles/therapeutic use , Indoles/administration & dosage , Humans , Lung Diseases, Interstitial/drug therapy , Female , Male , Middle Aged , Aged , Double-Blind Method , Pulmonary Fibrosis/drug therapy , Vital Capacity , Asian People , Surveys and Questionnaires , Tomography, X-Ray Computed , Treatment Outcome , East Asian People
7.
S Afr Fam Pract (2004) ; 66(1): e1-e8, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38572871

ABSTRACT

The series 'Mastering your Fellowship' provides examples of the question formats encountered in the written and clinical examinations, Part A of the Fellowship of the College of Family Physicians of South Africa (FCFP [SA]) examination. The series aims to help family medicine registrars (and supervisors) prepare for this examination.


Subject(s)
Educational Measurement , Fellowships and Scholarships , Humans , Clinical Competence , Family Practice/education , Physicians, Family
8.
11.
S Afr Fam Pract (2004) ; 66(1): e1-e10, 2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38299531

ABSTRACT

The series, 'Mastering your Fellowship', provides examples of the question formats encountered in the written and clinical examinations, Part A of the Fellowship of the College of Family Physicians (South Africa) (FCFP [SA]) examination. The series is aimed at helping family medicine registrars (and their supervisors) in preparing for this examination.


Subject(s)
Educational Measurement , Fellowships and Scholarships , Humans , Clinical Competence , Family Practice/education , Physicians, Family
12.
Eur Respir J ; 63(2)2024 Feb.
Article in English | MEDLINE | ID: mdl-38135442

ABSTRACT

BACKGROUND: Dyspnoea and cough can have a profound impact on the lives of patients with pulmonary fibrosis. We investigated the effects of nintedanib on the symptoms and impact of pulmonary fibrosis in patients with progressive pulmonary fibrosis (PPF) in the INBUILD trial using the Living with Pulmonary Fibrosis (L-PF) questionnaire. METHODS: Patients had a fibrosing interstitial lung disease (ILD) (other than idiopathic pulmonary fibrosis) of >10% extent on high-resolution computed tomography (HRCT) and met criteria for ILD progression within the prior 24 months. Patients were randomised 1:1 to receive nintedanib or placebo. Changes in L-PF questionnaire scores from baseline to week 52 were assessed using mixed models for repeated measures. RESULTS: In total, 663 patients were treated. Compared with placebo, there were significantly smaller increases (worsenings) in adjusted mean L-PF questionnaire total (0.5 versus 5.1), symptoms (1.3 versus 5.3), dyspnoea (4.3 versus 7.8) and fatigue (0.7 versus 4.0) scores in the nintedanib group at week 52. L-PF questionnaire cough score decreased in the nintedanib group and increased in the placebo group (-1.8 versus 4.3). L-PF questionnaire impacts score decreased slightly in the nintedanib group and increased in the placebo group (-0.2 versus 4.6). Similar findings were observed in patients with a usual interstitial pneumonia-like fibrotic pattern on HRCT and in patients with other fibrotic patterns on HRCT. CONCLUSION: Based on changes in L-PF questionnaire scores, nintedanib reduced worsening of dyspnoea, fatigue and cough and the impacts of ILD over 52 weeks in patients with PPF.


Subject(s)
Idiopathic Pulmonary Fibrosis , Indoles , Lung Diseases, Interstitial , Humans , Vital Capacity , Disease Progression , Lung Diseases, Interstitial/drug therapy , Idiopathic Pulmonary Fibrosis/drug therapy , Fibrosis , Dyspnea/drug therapy , Cough/drug therapy , Double-Blind Method
14.
Phys Chem Chem Phys ; 25(35): 23417-23434, 2023 Sep 13.
Article in English | MEDLINE | ID: mdl-37486006

ABSTRACT

We apply ultrashort X-ray laser pulses to track optically excited structural dynamics of [Ir2(dimen)4]2+ molecules in solution. In our exploratory study we determine angular correlations in the scattered X-rays, which comprise a complex fingerprint of the ultrafast dynamics. Model-assisted analysis of the experimental correlation data allows us to elucidate various aspects of the photoinduced changes in the excited molecular ensembles. We unambiguously identify that in our experiment the photoinduced transition dipole moments in [Ir2(dimen)4]2+ molecules are oriented perpendicular to the Ir-Ir bond. The analysis also shows that the ground state conformer of [Ir2(dimen)4]2+ with a larger Ir-Ir distance is mostly responsible for the formation of the excited state. We also reveal that the ensemble of solute molecules can be characterized with a substantial structural heterogeneity due to solvent influence. The proposed X-ray correlation approach offers an alternative path for studies of ultrafast structural dynamics of molecular ensembles in the liquid and gas phases.

15.
J Chem Theory Comput ; 19(15): 5122-5141, 2023 Aug 08.
Article in English | MEDLINE | ID: mdl-37458793

ABSTRACT

We present a fully self-consistent polarizable embedding (PE) model that does not suffer from unphysical boundary polarization. This is achieved through the use of the minimum-image convention (MIC) in the induced electrostatics. It is a simple yet effective approach that includes a more physically accurate description of the polarization throughout the molecular system. Using PE with MIC (PE-MIC), we shed new light on the limitations of commonly employed cutoff models, such as the droplet model, when used in PE calculations. Specifically, we investigate the effects of the unphysical polarization at the outer boundary by comparing induced dipoles and the associated electrostatic potentials, as well as some optical properties of solute-solvent and biomolecular systems. We show that the magnitude of the inaccuracies caused by the unphysical polarization depends on multiple parameters: the nature of the quantum subsystem and of the environment, the cutoff model and distance, and the calculated property.

16.
S Afr Fam Pract (2004) ; 65(1): e1-e8, 2023 05 16.
Article in English | MEDLINE | ID: mdl-37265133

ABSTRACT

The series, 'Mastering your Fellowship', provides examples of the question formats encountered in the written and clinical examinations, Part A of the Fellowship of the College of Family Physicians of South Africa (FCFP [SA]) examination. The series is aimed at helping family medicine registrars (and their supervisors) in preparing for this examination.


Subject(s)
Educational Measurement , Fellowships and Scholarships , Humans , Clinical Competence , Family Practice/education , Physicians, Family
17.
Adv Sci (Weinh) ; 10(21): e2206880, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37196414

ABSTRACT

Single-ion magnets (SIMs) constitute the ultimate size limit in the quest for miniaturizing magnetic materials. Several bottlenecks currently hindering breakthroughs in quantum information and communication technologies could be alleviated by new generations of SIMs displaying multifunctionality. Here, ultrafast optical absorption spectroscopy and X-ray emission spectroscopy are employed to track the photoinduced spin-state switching of the prototypical complex [Co(terpy)2 ]2+ (terpy = 2,2':6',2″-terpyridine) in solution phase. The combined measurements and their analysis supported by density functional theory (DFT), time-dependent-DFT (TD-DFT) and multireference quantum chemistry calculations reveal that the complex undergoes a spin-state transition from a tetragonally elongated doublet state to a tetragonally compressed quartet state on the femtosecond timescale, i.e., it sustains ultrafast Jahn-Teller (JT) photoswitching between two different spin multiplicities. Adding new Co-based complexes as possible contenders in the search for JT photoswitching SIMs will greatly widen the possibilities for implementing magnetic multifunctionality and eventually controlling ultrafast magnetization with optical photons.

19.
S Afr Fam Pract (2004) ; 65(1): e1-e8, 2023 01 05.
Article in English | MEDLINE | ID: mdl-36744492

ABSTRACT

The series 'Mastering your Fellowship' provides examples of the question formats encountered in the written and clinical examinations, Part A of the Fellowship of the College of Family Physicians of South Africa (FCFP [SA]) examination. The series is aimed at helping family medicine registrars (and their supervisors) in preparing for this examination.


Subject(s)
Educational Measurement , Fellowships and Scholarships , Humans , Clinical Competence , Family Practice/education , Physicians, Family
20.
Respirology ; 28(5): 465-474, 2023 05.
Article in English | MEDLINE | ID: mdl-36642509

ABSTRACT

BACKGROUND AND OBJECTIVE: In the INBUILD trial in patients with progressive fibrosing interstitial lung diseases (ILDs), nintedanib reduced the rate of decline in forced vital capacity (FVC) with an adverse event profile characterized mainly by gastrointestinal events. We analysed the effects of nintedanib in the subset of Asian subjects. METHODS: Subjects with fibrosing ILDs other than idiopathic pulmonary fibrosis who had shown progression of ILD at any time within the prior 24 months despite management deemed appropriate in clinical practice were randomized to receive nintedanib or placebo. We analysed the rate of decline in FVC (ml/year) over 52 weeks in all Asian subjects and in Asian subjects with a usual interstitial pneumonia (UIP)-like fibrotic pattern on high-resolution computed tomography (HRCT). RESULTS: One hundred sixty-four subjects in the INBUILD trial were of Asian race. The rate of decline in FVC (ml/year) over 52 weeks in this subgroup was -116.8 in the nintedanib group and -207.9 in the placebo group (difference: 91.0 [95% CI: 8.1, 173.9]; nominal p = 0.03). In Asian subjects with a UIP-like fibrotic pattern on HRCT, the rate of decline in FVC (ml/year) over 52 weeks was -130.1 in the nintedanib group and -224.2 in the placebo group (difference: 94.1 [5.5, 182.7]; nominal p = 0.04). Adverse events led to treatment discontinuation in 19.0% of the nintedanib group and 13.8% of the placebo group. CONCLUSION: In Asian patients with progressive fibrosing ILDs, nintedanib reduced the rate of decline in FVC with adverse events that were manageable for most patients.


Subject(s)
Idiopathic Pulmonary Fibrosis , Lung Diseases, Interstitial , Humans , Disease Progression , Lung Diseases, Interstitial/drug therapy , Idiopathic Pulmonary Fibrosis/drug therapy , Indoles/adverse effects , Vital Capacity , Fibrosis
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