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2.
Chirality ; 35(5): 298-310, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36775278

RESUMO

In this study, we exploit a recently developed fragment diabatization-based excitonic model, FrDEx, to simulate the electronic circular dichroism (ECD) spectra of three guanine-rich DNA sequences arranged in guanine quadruple helices with different topologies: thrombin binding aptamer (antiparallel), c-Myc promoter (parallel), and human telomeric sequence (3+1 hybrid). Starting from time-dependent density functional theory (TD-DFT) calculations with the M052X functional, we apply our protocol to parameterize the FrDEX Hamiltonian, which accounts for electron density overlap and includes both the coupling with charge transfer transitions and the effect of the surrounding bases on the local excitation of each chromophore. The TD-DFT/M052X spectral shapes are in good agreement with the experimental ones, the main source of discrepancy being related to the intrinsic error on the computed transition energies of guanine monomer. FrDEx spectra are fairly close to the reference TD-DFT ones, allowing a significant advance with respect to a more standard excitonic Hamiltonian. We also show that the ECD spectra are sensitive to the inclusion of the inner K + cation in the calculation.


Assuntos
DNA , Teoria Quântica , Humanos , Dicroísmo Circular , Estereoisomerismo , Eletrônica , Guanina
3.
Res Social Adm Pharm ; 19(4): 634-642, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36702707

RESUMO

BACKGROUND: Schools and faculties of pharmacy are responsible for selecting students to admit into the profession. Despite many similarities, admission processes, pharmacists' training, and scope of practice are different across jurisdictions. Students that are selected for admission may then differ in a number of ways, including by personality traits and other individual difference measures. OBJECTIVE: To compare the trait characteristics between students entering a New Zealand (NZ-University of Otago) and Canadian ((University of Waterloo) pharmacy programme and to compare their professional goals and role perceptions. METHODS: Incoming first year students at each university were invited to take an online questionnaire that included personality characteristics and potential predictors of involvement in pharmacists' roles: (1) the Big Five Inventory (openness, conscientiousness, extraversion, agreeableness, neuroticism); (2) the Achievement Goals Questionnaire-Revised; (3) the Rational Experiential Inventory; and (4) Counsellor Role Orientation. Statistical tests were conducted to determine if there were differences between entry level pharmacy students from NZ and Canada. RESULTS: 184 students (97/150 Otago, 87/118 Waterloo) completed the survey. On average, Waterloo students scored higher on agreeableness (M = 80 vs. 76, p = 0.06), conscientiousness (M = 70 vs. 68, p = 0.30), mastery-approach (M = 93 vs.90, p = 0.06), and faith-in-intuition (M = 67 vs. 61, p = 0.03) compared to Otago pharmacy students who were higher for openness M = 70 vs. 66, p = 0.09). An item measuring reliance on physicians for medicine advice was endorsed more by Otago pharmacy students (M = 35 vs. M = 15, p < 0.001). Items on time pressure (e.g., "It takes too much time to for a pharmacist to talk with a patient about the medication they receive") were higher for Otago students (M = 41 vs. M = 38, p = 0.26). Higher scores for pharmacist restriction ("There should be legal restrictions on what pharmacists can tell patients") were also seen among Otago students (M = 26 vs. M = 12, p < 0.001). There were important differences between entry level pharmacy students and practicing pharmacists in both jurisdictions. DISCUSSION: While entry-level pharmacy students had similar personality profiles, differences were observed in role expectations and in experiential learning orientation. This highlights differing societal views on the role of pharmacists in each respective country. Pharmacy schools should study their student bodies when designing their curricula and electives, helping ensure graduates feel like they have the training to do what they need to do. Future work will determine if these personality and learning goals influence students' preparation for practice.


Assuntos
Educação em Farmácia , Assistência Farmacêutica , Estudantes de Farmácia , Humanos , Objetivos , Canadá , Personalidade , Inquéritos e Questionários , Farmacêuticos , Papel Profissional
4.
J Phys Chem B ; 126(50): 10608-10621, 2022 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-36508709

RESUMO

Here we refine and assess two computational procedures aimed to include the effect of thermal fluctuations on the electronic spectra and the ultrafast excited state dynamics of multichromophore systems, focusing on DNA duplexes. Our approach is based on a fragment diabatization procedure that, from a given Quantum Mechanical (QM) reference method, can provide the parameters (energy and coupling) of the reference diabatic states on the basis of the isolated fragments, either for a purely electronic excitonic Hamiltonian (FrDEx) or a linear vibronic coupling Hamiltonian (FrD-LVC). After having defined the most cost-effective procedure for DNA duplexes on two smaller fragments, FrDEx is used to simulate the absorption and Electronic Circular Dichroism (ECD) spectra of (GC)5 sequences, including the coupling with the Charge Transfer (CT) states, on a number of structures extracted from classical Molecular Dynamics (MD) simulations. The computed spectra are close to the reference TD-DFT calculations and fully consistent with the experimental ones. We then couple MD simulations and FrD-LVC to simulate the interplay between local excitations and CT transitions, both intrastrand and interstrand, in GC and CG steps when included in a oligoGC or in oligoAT DNA sequence. We predict that for both sequences a substantial part of the photoexcited population on G and C decays, within 50-100 fs, to the corresponding intrastrand CT states. This transfer is more effective for GC steps that, on average, are more closely stacked than CG ones.


Assuntos
DNA , Teoria Quântica , DNA/química , Simulação de Dinâmica Molecular , Dicroísmo Circular , Teoria da Densidade Funcional
5.
Psychol Health ; : 1-25, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36317294

RESUMO

OBJECTIVE: Research on Open Science practices in Health Psychology is lacking. This meta-research study aimed to identify research question priorities and obtain consensus on the Top 5 prioritised research questions for Open Science in Health Psychology. METHODS AND MEASURES: An international Delphi consensus study was conducted. Twenty-three experts in Open Science and Health Psychology within the European Health Psychology Society (EHPS) suggested research question priorities to create a 'long-list' of items (Phase 1). Forty-three EHPS members rated the importance of these items, ranked their top five and suggested their own additional items (Phase 2). Twenty-four EHPS members received feedback on Phase 2 responses and then re-rated and re-ranked their top five research questions (Phase 3). RESULTS: The top five ranked research question priorities were: 1. 'To what extent are Open Science behaviours currently practised in Health Psychology?', 2. 'How can we maximise the usefulness of Open Data and Open Code resources?', 3. 'How can Open Data be increased within Health Psychology?', 4. 'What interventions are effective for increasing the adoption of Open Science in Health Psychology?' and 5. 'How can we increase free Open Access publishing in Health Psychology?'. CONCLUSION: Funding and resources should prioritise the research questions identified here.

6.
Chemistry ; 28(57): e202203016, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36202627

RESUMO

Invited for the cover of this issue is the group of G. A. Worth, F. Santoro and R. Improta at UCL, ICOOM-CNR and IBB-CNR. The image depicts charge transfer from guanine to cytosine in solvent after the absorption of light. Read the full text of the article at 10.1002/chem.202201731.


Assuntos
Citosina , Guanina , Clorofórmio , Solventes
7.
Chemistry ; 28(57): e202201731, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-35950519

RESUMO

We study the ultrafast photoactivated dynamics of the hydrogen bonded dimer Guanine-Cytosine in chloroform solution, focusing on the population of the Guanine→Cytosine charge transfer state (GC-CT), an important elementary process for the photophysics and photochemistry of nucleic acids. We integrate a quantum dynamics propagation scheme, based on a linear vibronic model parameterized through time dependent density functional theory calculations, with four different solvation models, either implicit or explicit. On average, after 50 fs, 30∼40 % of the bright excited state population has been transferred to GC-CT. This process is thus fast and effective, especially when transferring from the Guanine bright excited states, in line with the available experimental studies. Independent of the adopted solvation model, the population of GC-CT is however disfavoured in solution with respect to the gas phase. We show that dynamical solvation effects are responsible for this puzzling result and assess the different chemical-physical effects modulating the population of CT states on the ultrafast time-scale. We also propose some simple analyses to predict how solvent can affect the population transfer between bright and CT states, showing that the effect of the solute/solvent electrostatic interactions on the energy of the CT state can provide a rather reliable indication of its possible population.


Assuntos
Citosina , Ácidos Nucleicos , Clorofórmio , Guanina , Hidrogênio , Teoria Quântica , Solventes
8.
J Chem Theory Comput ; 18(6): 3718-3736, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35377648

RESUMO

In this contribution we present a mixed quantum-classical dynamical approach for the computation of vibronic absorption spectra of molecular aggregates and their nonadiabatic dynamics, taking into account the coupling between local excitations (LE) and charge-transfer (CT) states. The approach is based on an adiabatic (Ad) separation between the soft degrees of freedom (DoFs) of the system and the stiff vibrations, which are described by the quantum dynamics (QD) of wave packets (WPs) moving on the coupled potential energy surfaces (PESs) of the LE and CT states. These PESs are described with a linear vibronic coupling (LVC) Hamiltonian, parameterized by an overlap-based diabatization on the grounds of time-dependent density functional theory computations. The WPs time evolution is computed with the multiconfiguration time-dependent Hartree method, using effective modes defined through a hierarchical representation of the LVC Hamiltonian. The soft DoFs are sampled with classical molecular dynamics (MD), and the coupling between the slow and fast DoFs is included by recomputing the key parameters of the LVC Hamiltonians, specifically for each MD configuration. This method, named Ad-MD|gLVC, is applied to a perylene diimide (PDI) dimer in acetonitrile and water solutions, and it is shown to accurately reproduce the change in the vibronic features of the absorption spectrum upon aggregation. Moreover, the microscopic insight offered by the MD trajectories allows for a detailed understanding of the role played by the fluctuation of the aggregate structure on the shape of the vibronic spectrum and on the population of LE and CT states. The nonadiabatic QD predicts an extremely fast (∼50 fs) energy transfer between the two LEs. CT states have only a moderate effect on the absorption spectrum, despite the fact that after photoexcitation they are shown to acquire a fast and non-negligible population, highlighting their relevance in dictating the charge separation and transport in PDI-based optical devices.

9.
J Phys Chem A ; 125(40): 8912-8924, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34609880

RESUMO

In this contribution we present a quantum dynamical study of the photoexcited hydrogen bonded base pair adenine-thymine (AT) in a Watson-Crick arrangement. To that end, we parametrize Linear Vibronic Coupling (LVC) models with Time-Dependent Density Functional Theory (TD-DFT) calculations, exploiting a fragment diabatization scheme (FrD) we have developed to define diabatic states on the basis of individual chromophores in a multichromophoric system. Wavepacket propagations were run with the multilayer extension of the Multiconfiguration Time-Dependent Hartree method. We considered excitations to the three lowest bright states, a ππ* state of thymine and two ππ* states (La and Lb) of adenine, and we found that on the 100 fs time scale the main decay pathways involve intramonomer population transfers toward nπ* states of the same nucleobase. In AT this transfer is less effective than in the isolated nucleobases, because hydrogen bonding destabilizes the nπ* states. The population transfer to the A → T charge transfer state is negligible, making the ultrafast (femtosecond) decay through the proton coupled electron transfer mechanism unlikely, in line with experimental results in apolar solvents. The excitation energy transfer is also very small. We carefully compare the predictions of LVC Hamiltonians obtained with different sets of diabatic states, defined so to match either local states of the two separated monomers or the base pair adiabatic states in the Franck-Condon region. To that end we also extend the flexibility of the FrD-LVC approach, introducing a new strategy to define fragments diabatic states that account for the effect of the rest of the multichromohoric system through a Molecular Mechanics potential.

10.
Diabetes Res Clin Pract ; 181: 109087, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34637848

RESUMO

AIMS: This pilot study aimed to assess the acceptability of an intensive community-based intervention, and to get a preliminary estimate of the effect size of the intervention for people with type 2 diabetes in Kupang, Indonesia. METHODS: Pilot of a cluster randomised trial involving sixty-seven participants. The participants were recruited from four Primary Health Centres (PHCs), and were allocated into groups (intervention: 36; control: 31) based on the PHCs they were registered in. The 3-month intervention consisted of weekly group activities including physical activity and education. Control was usual care. The outcomes were change in HbA1c, medication adherence, and self-management behaviours. To test our intervention, we used a mixed linear model, with participants nested within cluster/health centre. RESULTS: Participants were 60% female, mean age 57, and had diabetes for an average of 4.5 years. Groups did not differ at baseline. Counter to prediction, no effects of the intervention over usual care were observed on the outcomes measured. However, both groups made statistically significant improvements in HbA1c (intervention from 8.3% ± 1.9 to 7.8% ± 1.8; control from 8.4% ± 2.6 to 7.9% ± 2.5). CONCLUSIONS: The effect of the intervention did not differ from usual care. However, both groups made improvements in HbA1c outcome, suggesting that the project might have indirectly triggered more intensive care for diabetes patients.


Assuntos
Diabetes Mellitus Tipo 2 , Autogestão , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/terapia , Feminino , Humanos , Indonésia/epidemiologia , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Projetos Piloto
11.
Health Psychol Behav Med ; 9(1): 917-932, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712515

RESUMO

This study aimed to describe patterns of use and attitudes towards a broad variety of substances for improving academic performance at a New Zealand university. 685 students (from 1800 invited) completed an online questionnaire (38% response rate). They were asked about their lifetime and current substance use for improving academic performance, as well as their reasons for use, attitudes and perceptions of: caffeine, alcohol, dietary supplements, prescription stimulants, other prescription substances, and illicit substances. 80% (95% CI: 76.3, 82.5) reported ever using any substance to help improve academic performance, mainly to stay awake and improve concentration. Caffeine (70%, 95% CI: 66.3, 73.3) and dietary supplements (32%, 95% CI: 28.3, 35.5) were most commonly used. 4% (95% CI: 2.7, 5.9) reported use of prescription stimulants, mostly methylphenidate, and another 4% (95% CI: 2.7, 5.9) reported using illicit substances for improving academic performance. Users of prescription stimulants were more likely than non-users to believe that they were safe, morally acceptable, and that they should be available legally for enhancing academic performance. We close with discussions on broadening the focus of substances for improving academic performance in public health debates. Further qualitative research from small countries is also needed to move towards a place-based approach for clarifying ethical implications, inform policy in universities, and understand how injustices are created through the use of and ability to purchase different substances.

12.
Molecules ; 26(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34443377

RESUMO

We here investigate the Electronic Circular Dichroism (ECD) Spectra of two representative Guanine-rich sequences folded in a Quadruple helix (GQ), by using a recently developed fragment diabatisation based excitonic model (FrDEx). FrDEx can include charge transfer (CT) excited states and consider the effect of the surrounding monomers on the local excitations (LEs). When applied to different structures generated by molecular dynamics simulations on a fragment of the human telomeric sequence (Tel21/22), FrDEx provides spectra fully consistent with the experimental one and in good agreement with that provided by quantum mechanical (QM) method used for its parametrization, i.e., TD-M05-2X. We show that the ECD spectrum is moderately sensitive to the conformation adopted by the bases of the loops and more significantly to the thermal fluctuations of the Guanine tetrads. In particular, we show how changes in the overlap of the tetrads modulate the intensity of the ECD signal. We illustrate how this correlates with changes in the character of the excitonic states at the bottom of the La and Lb bands, with larger LE and CT involvement of bases that are more closely stacked. As an additional test, we utilised FrDEx to compute the ECD spectrum of the monomeric and dimeric forms of a GQ forming sequence T30695 (5'TGGGTGGGTGGGTGGG3'), i.e., a system containing up to 24 Guanine bases, and demonstrated the satisfactory reproduction of the experimental and QM reference results. This study provides new insights on the effects modulating the ECD spectra of GQs and, more generally, further validates FrDEx as an effective tool to predict and assign the spectra of closely stacked multichromophore systems.


Assuntos
Dicroísmo Circular , DNA/química , Elétrons , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , Dimerização , Espectroscopia de Ressonância Magnética , Temperatura
13.
J Chem Theory Comput ; 17(8): 4660-4674, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34270258

RESUMO

We introduce a method (FrD-LVC) based on a fragment diabatization (FrD) for the parametrization of a linear vibronic coupling (LVC) model suitable for studying the photophysics of multichromophore systems. In combination with effective quantum dynamics (QD) propagations with multilayer multiconfigurational time-dependent Hartree (ML-MCTDH), the FrD-LVC approach gives access to the study of the competition between intrachromophore decays, like those at conical intersections, and interchromophore processes, like exciton localization/delocalization and the involvement of charge-transfer (CT) states. We used FrD-LVC parametrized with time-dependent density functional theory (TD-DFT) calculations, adopting either CAM-B3LYP or ωB97X-D functionals, to study the ultrafast photoexcited QD of a guanine-cytosine (GC) hydrogen-bonded pair, within a Watson-Crick arrangement, considering up to 12 coupled diabatic electronic states and the effect of all of the 99 vibrational coordinates. The bright excited states localized on C and, especially, on G are predicted to be strongly coupled to the G → C CT state, which is efficiently and quickly populated after an excitation to any of the four lowest energy bright local excited states. Our QD simulations show that more than 80% of the excited population on G and ∼50% of that on C decay to this CT state in less than 50 fs. We investigate the role of vibronic effects in the population of the CT state and show that it depends mainly on its large reorganization energy so that it can occur even when it is significantly less stable than the bright states in the Franck-Condon region. At the same time, we document that the formation of the GC pair almost suppresses the involvement of dark nπ* excited states in the photoactivated dynamics.


Assuntos
Citosina/química , Guanina/química , Pareamento de Bases , Citosina/metabolismo , Teoria da Densidade Funcional , Guanina/metabolismo , Ligação de Hidrogênio
14.
Health Psychol Behav Med ; 9(1): 436-455, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34104569

RESUMO

Background: Dependent variables in health psychology are often counts, for example, of a behaviour or number of engagements with an intervention. These counts can be very strongly skewed, and/or contain large numbers of zeros as well as extreme outliers. For example, 'How many cigarettes do you smoke on an average day?' The modal answer may be zero but may range from 0 to 40+. The same can be true for minutes of moderate-to-vigorous physical activity. For some people, this may be near zero, but take on extreme values for someone training for a marathon. Typical analytical strategies for this data involve explicit (or implied) transformations (smoker v. non-smoker, log transformations). However, these data types are 'counts' (i.e. non-negative whole numbers) or quasi-counts (time is ratio but discrete minutes of activity could be analysed as a count), and can be modelled using count distributions - including the Poisson and negative binomial distribution (and their zero-inflated and hurdle extensions, which alloweven more zeros). Methods: In this tutorial paper I demonstrate (in R, Jamovi, and SPSS) the easy application of these models to health psychology data, and their advantages over alternative ways of analysing this type of data using two datasets - one highly dispersed dependent variable (number of views on YouTube, and another with a large number of zeros (number of days on which symptoms were reported over a month). Results: The negative binomial distribution had the best fit for the overdispersed number of views on YouTube. Negative binomial, and zero-inflated negative binomial were both good fits for the symptom data with over-abundant zeros. Conclusions: In both cases, count distributions provided not just a better fit but would lead to different conclusions compared to the poorly fitting traditional regression/linear models.

15.
Phys Chem Chem Phys ; 23(14): 8181-8199, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33875988

RESUMO

We concisely review the main methodological approaches to model nonadiabatic dynamics in isotropic solutions and their applications. Three general classes of models are identified as the most used to include solvent effects in the simulations. The first model describes the solvent as a set of harmonic collective modes coupled to the solute degrees of freedom, and the second as a continuum, while the third explicitly includes solvent molecules in the calculations. The issues related to the use of these models in semiclassical and quantum dynamical simulations are discussed, as well as the main limitations and perspectives of each approach.

16.
Molecules ; 26(6)2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804640

RESUMO

We have recently proposed a protocol for Quantum Dynamics (QD) calculations, which is based on a parameterisation of Linear Vibronic Coupling (LVC) Hamiltonians with Time Dependent (TD) Density Functional Theory (TD-DFT), and exploits the latest developments in multiconfigurational TD-Hartree methods for an effective wave packet propagation. In this contribution we explore the potentialities of this approach to compute nonadiabatic vibronic spectra and ultrafast dynamics, by applying it to the five nucleobases present in DNA and RNA. For all of them we computed the absorption spectra and the dynamics of ultrafast internal conversion (100 fs timescale), fully coupling the first 2-3 bright states and all the close by dark states, for a total of 6-9 states, and including all the normal coordinates. We adopted two different functionals, CAM-B3LYP and PBE0, and tested the effect of the basis set. Computed spectra are in good agreement with the available experimental data, remarkably improving over pure electronic computations, but also with respect to vibronic spectra obtained neglecting inter-state couplings. Our QD simulations indicate an effective population transfer from the lowest energy bright excited states to the close-lying dark excited states for uracil, thymine and adenine. Dynamics from higher-energy states show an ultrafast depopulation toward the more stable ones. The proposed protocol is sufficiently general and automatic to promise to become useful for widespread applications.


Assuntos
DNA/química , Modelos Químicos , RNA/química , Adenina/química , Citosina/química , Timina/química , Uracila/química
17.
Res Social Adm Pharm ; 17(3): 545-552, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32482588

RESUMO

BACKGROUND: Pharmacists increasingly need to provide patient centred activities like medicine management (e.g., medicine use review/home medicine review), screening for chronic illness (e.g., point of care testing for cardiovascular diseases including hypertension and hypercholesterolemia), treatment for chronic conditions (e.g., warfarin for thrombotic prophylaxis), and primary care treatment (trimethoprim, emergency contraceptive pill, and sildenafil). However, the adoption of patient-centred services into practice is still low, and it not known which pharmacist characteristics are associated with the adoption of these services. OBJECTIVE: The primary objective of this study was to investigate whether personality and other characteristics of pharmacy graduates are associated with their intention to provide patient-centred services in the future. METHODS: The study design was a cross-sectional survey of pharmacy graduates from the University of Otago at the end of 2017. The web-based survey involved several potential determinants: (1) the Achievement Goals Questionnaire (Revised), (2) five-factor ('Big Five') model of personality, (3) decision-making style using the Rational Experiential inventory, (4) general self-efficacy, (5) sense of belonging to the pharmacy profession. Additionally, interest in provision of services was assessed. RESULTS: A total of 83 graduates completed the survey (response rate 63%, female 64%, age 22.5 years, SD: 1.7). Intention to provide patient-centred services was associated with higher: conscientiousness, agreeableness, and extraversion; mastery-approach; self-efficacy; and sense of belonging to the profession. Relative to the New Zealand population norms, these students were higher in conscientiousness and lower in neuroticism. Graduates were more interested in providing new patient-centred roles than more traditional services. CONCLUSION: Overall, pharmacy graduates were very positive regarding their future involvement in patient-centred services. Pharmacy graduates' sense of self-efficacy and a sense of belonging in the profession were associated with interest in patient-centred roles. Increasing their self-efficacy and sense of belonging to the profession and building on their enthusiasm as new graduates are key to greater provision of patient-centred activities.


Assuntos
Assistência Farmacêutica , Farmácias , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Nova Zelândia , Farmacêuticos , Inquéritos e Questionários , Adulto Jovem
18.
J Chem Theory Comput ; 17(1): 405-415, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33378185

RESUMO

We here propose a general and flexible approach, based on fragment diabatization, which incorporates charge transfer states and significantly increases the reliability of excitonic Hamiltonians for systems where the chromophores are very close. This model (FrDEx) is used to compute the electronic circular dichroism and absorption spectra of two prototype guanine-rich DNA sequences folded in quadruple helices (GQs), i.e., a fragment of the human telomeric sequence (Tel21, antiparallel), and (TGGGGT)4 (TG4T, parallel). Calculations on different subsets of Tel21 and TG4T, from dimers to tetramers, show that FrDEx provides spectra close to the reference full quantum mechanical (QM) ones (obtained with time-dependent density functional theory), with significant improvements with respect to "standard" excitonic Hamiltonians. Furthermore, these tests enable the most cost-effective procedure for the whole GQ to be determined. FrDEx spectra of Tel21 and TG4T are also in good agreement with the QM and experimental ones and give access to interesting insights into the chemical-physical effects modulating the spectral signals. FrDEx could be profitably used to investigate many other biological and nanotechnological materials, from DNA to (opto)electronic polymers.


Assuntos
Quadruplex G , Guanina/química , DNA/química , Dimerização , Elétrons , Modelos Moleculares , Teoria Quântica
19.
Memory ; 28(5): 589-597, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32378455

RESUMO

Cognitive scientists have firmly established that memory is vulnerable to decay and distortion. Yet laypeople - who may be required to evaluate memory evidence as jurors - have shown less awareness of memory fallibility. Although we might expect laypeople's knowledge of memory to have improved over time, research has yet to explore this issue while accounting for possible age-related changes. We administered a modified version of the Beliefs about Memory Survey (BAMS) to a community sample, investigating patterns of beliefs relating to memory permanence, repression of traumatic memories, and memory reconstruction. Older participants were more likely than younger participants to believe that traumatic memories can be repressed, while younger participants were more likely than their older counterparts to believe that memory is permanent, but also that memory is malleable. We assessed whether these beliefs were stable over time, by comparing our data to a sample of data collected 25 years earlier. Although contemporary beliefs about the repression of traumatic memories and memory reconstruction were more aligned with expert opinion than those of 25 years ago, beliefs about memory permanence were not. These findings highlight the need for continued education about memory and its shortcomings. We discuss ways of improving decisions about memory evidence.


Assuntos
Prova Pericial , Memória/fisiologia , Repressão Psicológica , Adulto , Fatores Etários , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Inquéritos e Questionários
20.
Glob Public Health ; 15(8): 1168-1181, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32290768

RESUMO

In 1983, the Indonesian government established Pos Pelayanan Terpadu (Integrated Health Post) - commonly known as Posyandu, an outreach programme for improving mothers' and children's health, including immunisation. However, child immunisation coverage is still far below national and world targets. There is also wide variation among regions, with low rates found in areas outside Java. This study aimed to explore mothers' experiences in immunising their children through Posyandu in East Nusa Tenggara, and West Sumatera, two provinces located outside Java Island. Fifty-three mothers were involved in six Focus Group Discussion (FGDs). The discussions were recorded and transcribed verbatim in the original language. The transcripts were translated into English, coded with Nvivo, and analysed for common themes. This study showed that the success of the immunisation programme through Posyandu relied on the role of community-based health workers. Their ability to integrate with the community increased people's trust. This trust encouraged mothers to immunise their children, despite their limited knowledge about immunisation. The other barrier often encountered by the mothers in immunising their children was that the fathers did not allow them to do so. Therefore, collaborative work with the whole community is needed to improve the performance of an outreach programme.


Assuntos
Relações Comunidade-Instituição , Programas de Imunização , Imunização , Mães , Criança , Feminino , Grupos Focais , Humanos , Imunização/estatística & dados numéricos , Programas de Imunização/organização & administração , Indonésia , Mães/psicologia , Avaliação de Programas e Projetos de Saúde , Pesquisa Qualitativa
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