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1.
Hum Brain Mapp ; 42(1): 128-138, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33089953

RESUMEN

The purpose of this study was to develop and evaluate a new, open-source MR-compatible device capable of assessing unipedal and bipedal lower extremity movement with minimal head motion and high test-retest reliability. To evaluate the prototype, 20 healthy adults participated in two magnetic resonance imaging (MRI) visits, separated by 2-6 months, in which they performed a visually guided dorsiflexion/plantar flexion task with their left foot, right foot, and alternating feet. Dependent measures included: evoked blood oxygen level-dependent (BOLD) signal in the motor network, head movement associated with dorsiflexion/plantar flexion, the test-retest reliability of these measurements. Left and right unipedal movement led to a significant increase in BOLD signal compared to rest in the medial portion of the right and left primary motor cortex (respectively), and the ipsilateral cerebellum (FWE corrected, p < .001). Average head motion was 0.10 ± 0.02 mm. The test-retest reliability was high for the functional MRI data (intraclass correlation coefficients [ICCs]: >0.75) and the angular displacement of the ankle joint (ICC: 0.842). This bipedal device can robustly isolate activity in the motor network during alternating plantarflexion and dorsiflexion with minimal head movement, while providing high test-retest reliability. Ultimately, these data and open-source building instructions will provide a new, economical tool for investigators interested in evaluating brain function resulting from lower extremity movement.


Asunto(s)
Cerebelo/fisiología , Técnicas de Diagnóstico Neurológico/instrumentación , Diseño de Equipo/normas , Neuroimagen Funcional , Movimientos de la Cabeza/fisiología , Extremidad Inferior/fisiología , Actividad Motora/fisiología , Corteza Motora/fisiología , Red Nerviosa/fisiología , Desempeño Psicomotor/fisiología , Adulto , Cerebelo/diagnóstico por imagen , Femenino , Neuroimagen Funcional/normas , Humanos , Imagen por Resonancia Magnética , Masculino , Corteza Motora/diagnóstico por imagen , Red Nerviosa/diagnóstico por imagen , Reproducibilidad de los Resultados , Adulto Joven
2.
J Clin Psychol ; 77(6): 1307-1329, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33449365

RESUMEN

OBJECTIVE: To better understand how therapists facilitate client goal attainment in therapy, we analyzed therapists' future-oriented actions in good outcome cases in which clients recorded high ratings on goal items in the Working Alliance Inventory-Short Revised. METHOD: We selected clients who were within the clinical range (OQ-45.2) at pretreatment, demonstrated reliable change at the end of treatment, and recorded high WAI client goals scores early in treatment. Qualitative analyses of transcripts of the initial three sessions and client posttreatment interviews were integrated into a combined analysis to identify themes across the two separate sets of findings. RESULTS: Therapist future-oriented activity included: (1) Picking up explicit and implicit intentions; (2) using linguistic devices, such as meta-communication, action language, and hedging; (3) using evocative interventions; and (4) nudging the client into practicing change. Core finding: Therapists aligned with clients' directionality in a forward-driven, gradually evolving process. CONCLUSION: Conceptual and clinical implications are discussed.


Asunto(s)
Objetivos , Relaciones Profesional-Paciente , Humanos , Motivación , Resultado del Tratamiento
3.
Angew Chem Int Ed Engl ; 59(10): 4099-4105, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-31872927

RESUMEN

Defect passivation has been demonstrated to be effective in improving the radiative recombination of charge carriers in perovskites, and consequently, the device performance of the resultant perovskite light-emitting diodes (LEDs). State-of-the-art useful passivation agents in perovskite LEDs are mostly organic chelating molecules that, however, simultaneously sacrifice the charge-transport properties and thermal stability of the resultant perovskite emissive layers, thereby deteriorating performance, and especially the operational stability of the devices. We demonstrate that lithium halides can efficiently passivate the defects generated by halide vacancies and reduce trap state density, thereby suppressing ion migration in perovskite films. Efficient green perovskite LEDs based on all-inorganic CsPbBr3 perovskite with a peak external quantum efficiency of 16.2 %, as well as a high maximum brightness of 50 270 cd m-2 , are achieved. Moreover, the device shows decent stability even under a brightness of 104  cd m-2 . We highlight the universal applicability of defect passivation using lithium halides, which enabled us to improve the efficiency of blue and red perovskite LEDs.

4.
Lancet ; 392(10141): 41-50, 2018 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-29961638

RESUMEN

BACKGROUND: The management of people with multiple chronic conditions challenges health-care systems designed around single conditions. There is international consensus that care for multimorbidity should be patient-centred, focus on quality of life, and promote self-management towards agreed goals. However, there is little evidence about the effectiveness of this approach. Our hypothesis was that the patient-centred, so-called 3D approach (based on dimensions of health, depression, and drugs) for patients with multimorbidity would improve their health-related quality of life, which is the ultimate aim of the 3D intervention. METHODS: We did this pragmatic cluster-randomised trial in general practices in England and Scotland. Practices were randomly allocated to continue usual care (17 practices) or to provide 6-monthly comprehensive 3D reviews, incorporating patient-centred strategies that reflected international consensus on best care (16 practices). Randomisation was computer-generated, stratified by area, and minimised by practice deprivation and list size. Adults with three or more chronic conditions were recruited. The primary outcome was quality of life (assessed with EQ-5D-5L) after 15 months' follow-up. Participants were not masked to group assignment, but analysis of outcomes was blinded. We analysed the primary outcome in the intention-to-treat population, with missing data being multiply imputed. This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN06180958. FINDINGS: Between May 20, 2015, and Dec 31, 2015, we recruited 1546 patients from 33 practices and randomly assigned them to receive the intervention (n=797) or usual care (n=749). In our intention-to-treat analysis, there was no difference between trial groups in the primary outcome of quality of life (adjusted difference in mean EQ-5D-5L 0·00, 95% CI -0·02 to 0·02; p=0·93). 78 patients died, and the deaths were not considered as related to the intervention. INTERPRETATION: To our knowledge, this trial is the largest investigation of the international consensus about optimal management of multimorbidity. The 3D intervention did not improve patients' quality of life. FUNDING: National Institute for Health Research.


Asunto(s)
Enfermedad Crónica/terapia , Multimorbilidad , Atención Dirigida al Paciente , Anciano , Enfermedad Crónica/psicología , Inglaterra , Femenino , Estudios de Seguimiento , Humanos , Comunicación Interdisciplinaria , Colaboración Intersectorial , Masculino , Persona de Mediana Edad , Grupo de Atención al Paciente , Calidad de Vida/psicología , Escocia , Autocuidado/psicología
5.
Psychother Res ; 29(7): 959-970, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-29950137

RESUMEN

Objective: The aim of this study was to gain knowledge about how the integration of personal and professional experiences affects therapeutic work. Method: Therapists (N = 14) who had been recommended by their leaders at their individual workplaces were interviewed twice with semi-structured qualitative interviews, which were then subjected to thematic and Interpretative Phenomenological Analysis. Results: All the therapists in the sample described their personal qualities as an experienced tension between their personal strengths and vulnerabilities in the therapeutic setting. This tension came to expression through four subordinate themes: (a) The tension between perceiving oneself as a helper while dealing with one's own needs for attention and care; (b) The tension between the ability for embodied listening to the patient while tuning into oneself; (c) The tension between staying present while handling aggression and rejection from clients; and (d) The tension in striving for a constructive balance between closeness and distance. Conclusion: The results point to ways in which the personal selves of the therapists may affect their professional role performance. Drawing upon previous research and literature on the topic, the paper discusses how therapists' personal qualities are experienced as affecting their work and suggests several implications for psychotherapy training and practice.


Asunto(s)
Personal de Salud , Psicoterapia , Autoevaluación (Psicología) , Rendimiento Laboral , Adulto , Personal de Salud/psicología , Humanos , Investigación Cualitativa
6.
Psychother Res ; 28(5): 776-792, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-28060577

RESUMEN

OBJECTIVE: To explore the nature of professional wisdom, through learning from the experiences of a group of highly experienced senior therapists. METHOD: Twelve senior psychotherapists took part in qualitative in-depth interviews about their professional role and their views around a range of aspects of therapy theory and practice. Interview transcripts were subjected to thematic analysis. RESULTS: The analysis yielded nine wisdom themes, clustered within three domains. Each domain represented efforts to resolve dilemmas arising from the experience of being a therapist, around the use of theory in psychotherapy practice, the type of therapeutic relationship that is most helpful for clients, and the experience of therapeutic failure. CONCLUSIONS: Therapist wisdom can be viewed as a form of contextualized knowledge, which functions as a source of emergent insights that arise as responses to the limitations of prevailing ways of thinking. Research into the nature of therapist wisdom draws attention to sources of knowledge within philosophy and the humanities that have the potential to enhance therapy practice and contribute to our understanding of therapist expertise.


Asunto(s)
Competencia Clínica , Personal de Salud , Relaciones Profesional-Paciente , Psicoterapia , Adulto , Femenino , Personal de Salud/psicología , Humanos , Conocimiento , Masculino , Persona de Mediana Edad , Investigación Cualitativa
7.
Inorg Chem ; 56(5): 2985-2991, 2017 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-28186747

RESUMEN

The electronic structures of a series of gallium complexes are examined using X-ray absorption spectroscopy (XAS) in combination with ab initio calculations. The chemical states of Ga are strongly affected by the ligands and the bonding environment. For complexes containing multiple gallium sites, we demonstrate that XAS can identify the chemical state of each unique gallium center. A reliable understanding of the chemical nature of the core element in a coordination complex with strong core-ligand interaction can be obtained only when both experimental and theoretical approaches are combined.

8.
Phys Chem Chem Phys ; 19(4): 3182-3191, 2017 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-28083591

RESUMEN

GeOx nanoparticles (NPs) are of growing interest in lithium storage and optoelectronics. GeOx NPs prepared by chemical reduction, exposed to air or retained under N2, then annealed under H2 at various temperatures are studied herein using soft X-ray spectroscopy. We find that fresh and air-exposed GeOx NPs evolve rather differently under annealing. The fresh GeOx NPs start as a very amorphous heterogeneous mixture of GeOx and Ge, and during annealing both the valence band and conduction band edges evolve. In contrast, the air-exposed GeOx NPs initially contain quartz-phase GeO2, and during annealing only the conduction band edge evolves due to increased oxygen vacancies forming unoccupied defect states (the valence band does not change until annealing at high temperture, at which point almost all of the GeO2 is removed). These findings suggest a preparation and annealing strategy that could be used to tailor GeOx NPs for their intended use in lithium storage or optoelectronic applications.

9.
Nano Lett ; 16(7): 4720-5, 2016 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-27337149

RESUMEN

Organic-inorganic lead perovskites have shown great promise as photovoltaic materials, and within this class of materials (CH3NH3)PbI3-xClx is of particular interest. Herein we use soft X-ray spectroscopy and density functional theory calculations to demonstrate that the methylammonium cations in a typical photovoltaic layer may dissociate into a metastable arrangement of CH3I-Pb2 defects and trapped NH3. The possibility that other metastable configurations of the organic components in (CH3NH3)PbI3-xClx is rarely considered but adds an entirely new dimension in understanding the charge trapping, ionic transport, and structural degradation mechanisms in these materials. Understanding the influence of these other configurations is of critical importance for further improving the performance of these photovoltaics.

10.
Chemistry ; 22(32): 11170-5, 2016 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-27305606

RESUMEN

Cooperative performance of mixed-valent Eu(2+) /Eu(3+) in single-compound phosphors offers significant advantages in color rendering and luminescence efficiency, but their synthesis is challenging because of Eu(2+) oxidation. Using the tunable nature of the metal-ion nodes in metal-organic frameworks (MOFs), we present an in situ reduction and crystallization route for preparing MOFs and doping Eu(2+) /Eu(3+) with a controlled ratio. These materials exhibit rich photoluminescence, including intrinsic- and sensitized-emissions of Eu(2+) and Eu(3+) , and long-lived luminescence from charge transfer. Color rendering can be easily achieved by fine-tuning the valence states of Eu. A linear relation between temperature and the intensity ratio of Eu(2+) /Eu(3+) emissions provides outstanding properties for applications as self-calibrated luminescent thermometers with a wide working temperature range. Further incorporation of Tb(3+) into the MOFs results in white light, utilizing all Eu(2+) ,Tb(3+) , and Eu(3+) emissions in a single crystalline lattice.

11.
Psychother Res ; 26(6): 737-49, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-26211506

RESUMEN

OBJECTIVE: To investigate how psychotherapists' lives and relationships are influenced by their work. METHOD: Twelve senior psychotherapists took part in qualitative interviews. RESULTS: Thematic analysis yielded four significant themes: (i) it has been a privilege to know and contribute, and to be allowed to grow personally; (ii) facing suffering and destructiveness has been a burden; (iii) being a therapist has had an impact on my personal relationships-for better and worse; and (iv) I have needed to construct a way of living that allowed me to continue to do the work. CONCLUSION: Working as a therapist seem to imply a potential for developing openness, tolerance, and creativity, while being vulnerable to becoming overwhelmed with responsibility and feelings of inadequacy, isolation, and despair.


Asunto(s)
Personal de Salud/psicología , Psicoterapia , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Investigación Cualitativa
12.
J Chem Phys ; 143(22): 224704, 2015 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-26671393

RESUMEN

The electronic structure of [6,6]-phenyl C61 butyric acid methyl ester (PCBM), poly(3-hexylthiophene) (P3HT), and P3HT/PCBM blends is studied using soft X-ray emission and absorption spectroscopy and density functional theory calculations. We find that annealing reduces the HOMO-LUMO gap of P3HT and P3HT/PCBM blends, whereas annealing has little effect on the HOMO-LUMO gap of PCBM. We propose a model connecting torsional disorder in a P3HT polymer to the HOMO-LUMO gap, which suggests that annealing helps to decrease the torsional disorder in the P3HT polymers. Our model is used to predict the characteristic length scales of the flat P3TH polymer segments in P3HT and P3HT/PCBM blends before and after annealing. Our approach may prove useful in characterizing organic photovoltaic devices in situ or even in operando.


Asunto(s)
Fulerenos/química , Polímeros/química , Teoría Cuántica , Tiofenos/química , Electrones
13.
Front Psychol ; 15: 1390579, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38895499

RESUMEN

Background: In both routine practice contexts and research studies, evidence from standardized self-report symptom measures, administered pre- and post-treatment, is predominantly used to determine whether psychotherapy has been successful. Understanding the nature of unsuccessful psychotherapy requires an ability to evaluate the credibility of outcome data generated by such techniques. An important body of research has identified discrepancies between outcomes assessed through symptom measures and those obtained from other sources. However, not enough is known about the extent to which such paradoxical outcomes exist. Objective: This study analyzes the relationship between outcomes, as assessed by a standardized self-report measure, and as assessed by ratings of young people's descriptions of change at post-counseling interviews. Methods: Participants were 50 young people (13-16 years old) who had taken part in a trial of up to 10 weeks of school-based humanistic counseling. Our primary standardized measure was the Young Person's CORE (YP-CORE). To assess young people's experiences of counseling change, three independent raters scrutinized transcripts of post-counseling interviews, and scored levels of helpfulness on a 1 (Not at all helpful) to 10 (Extremely helpful) scale. Inter-rater reliabilities were 0.94 (Cronbach's Alpha) and 0.96 (McDonald's Omega). Sensitivity analyses were conducted to explore relationships between helpfulness ratings and other outcome measures, i.e., satisfaction with counseling (ESQ) and the Goal-Based-Outcome Tool (GBO), and process measures, i.e., the Working Alliance Inventory (WAI-S) and the Barret Lennard Relationship Inventory (BLRI). Results: Multilevel analysis indicated that helpfulness ratings were not significantly associated with changes in YP-CORE scores. Analyzed categorically, 38% of those showing reliable improvement on the standardized measure were below the median for self-described helpfulness, and 47% of those not showing reliable change were at or above the median for self-described helpfulness. Sensitivity analyses demonstrated closer correlations between helpfulness ratings and other outcome measures (ESQ and GBO), and between helpfulness ratings and process measures (WAI-S and BLRI). Discussion: Our results raise questions about reliance on symptom change outcome measures for defining treatment success and failure, given their disparity with clients' own descriptions of the helpfulness of therapy. Implications for practice and research are discussed.

14.
Am Psychol ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39133579

RESUMEN

To improve the provision of psychotherapy, many countries have now established clinical practice guidelines for the treatment of specific disorders and mental health concerns. These guidelines have typically been based on evidence from meta-analyses of randomized clinical trials with minimal consideration of findings from qualitative research designs. This said, there has been growing interest in incorporating qualitative research in guideline development processes from both stakeholders and guideline development bodies. In this international collaboration, 19 qualitative psychotherapy researchers from 10 countries articulated the benefits of including qualitative findings within the guideline development process and generated recommendations for guideline developers. The underlying question of this report was "Why and how should qualitative research be used in efforts to develop guidance for psychotherapy practice?" The advantages of reviewing qualitative findings included the ability to identify treatment patterns at the level of in-session dynamics, cultural contexts, interpersonal relationships, and internal experiences, thereby creating guidance that is responsive to clients' needs in the moment-to-moment therapy process. Recommendations are offered at the systemic level (e.g., guideline formation processes, methods of education, research funding priorities). Also, methodological advice is offered for guideline developers when selecting to incorporate qualitative research in the implementation of an expanded guideline development process. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

15.
Chemistry ; 18(10): 2912-22, 2012 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-22290810

RESUMEN

We demonstrate that the electronic structure of mesoporous silicon is affected by adsorption of nitro-based explosive molecules in a compound-selective manner. This selective response is demonstrated by probing the adsorption of two nitro-based molecular explosives (trinitrotoluene and cyclotrimethylenetrinitramine) and a nonexplosive nitro-based aromatic molecule (nitrotoluene) on mesoporous silicon using soft X-ray spectroscopy. The Si atoms strongly interact with adsorbed molecules to form Si-O and Si-N bonds, as evident from the large shifts in emission energy present in the Si L(2,3) X-ray emission spectroscopy (XES) measurements. Furthermore, we find that the energy gap (band gap) of mesoporous silicon changes depending on the adsorbant, as estimated from the Si L(2,3) XES and 2p X-ray absorption spectroscopy (XAS) measurements. Our ab initio molecular dynamics calculations of model compounds suggest that these changes are due to spontaneous breaking of the nitro groups upon contacting surface Si atoms. This compound-selective change in electronic structure may provide a powerful tool for the detection and identification of trace quantities of airborne explosive molecules.

16.
Front Psychol ; 13: 1048665, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36467223

RESUMEN

Historically, research and practice of psychotherapy have been conducted within conceptual frameworks defined in terms of theoretical models. These models are in turn guided by meta-theories about the purpose of psychotherapy and its place in society. An image of psychotherapy that underpins much contemporary practice is the idea that therapy operates as an intervention that involves the implementation and application of a pre-existing theoretical model or set of empirically validated procedures. The present paper introduces the idea that it may be valuable to regard psychotherapy not as an intervention but instead as a process of making, in the sense of offering a cultural space for the co-construction of meaningful and satisfying ways of living that draw on shared cultural resources. We offer an overview of what a therapy of making might look like, followed by an account of theoretical perspectives, both within the psychotherapy literature and derived from wider philosophical and social science sources, that we have found valuable in terms of making sense of this way of thinking about practice. Our conclusion is that we need something in addition to theory-specific and protocol-driven therapies, in order to be able to incorporate the unexpected, the not-before-met perspective, event or practice of living, and to be open towards the radically new, the given, and the unknown.

17.
Nat Commun ; 13(1): 6464, 2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36309496

RESUMEN

In commercial Li-ion batteries, the internal short circuits or over-lithiation often cause structural transformation in electrodes and may lead to safety risks. Herein, we investigate the over-discharged mechanism of LiCoO2/graphite pouch cells, especially spatially resolving the morphological, surface phase, and local electronic structure of LiCoO2 electrode. With synchrotron-based X-ray techniques and Raman mapping, together with spectroscopy simulations, we demonstrate that over-lithiation reaction is a surface effect, accompanied by Co reduction and surface structure transformation to Li2CoO2/Co3O4/CoO/Li2O-like phases. This surface chemical distribution variation is relevant to the depth and exposed crystalline planes of LiCoO2 particles, and the distribution of binder/conductive additives. Theoretical calculations confirm that Li2CoO2-phase has lower electronic/ionic conductivity than LiCoO2-phase, further revealing the critical effect of distribution of conductive additives on the surface chemical heterogeneity evolution. Our findings on such surface phenomena are non-trivial and highlight the capability of synchrotron-based X-ray techniques for studying the spatial chemical phase heterogeneity.

18.
Front Psychol ; 12: 742676, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34552542

RESUMEN

The adoption of a pluralistic perspective on research design, processes of data collection and analysis and dissemination of findings, has the potential to enable psychotherapy research to make a more effective contribution to building a just society. A review of the key features of the concept of pluralism is followed by a historical analysis of the ways in which research in counselling, psychotherapy and related disciplines has moved in the direction of a pluralistic position around knowledge creation. Core principles of a pluralistic approach to research are identified and explored in the context of a critical case study of contemporary research into psychotherapy for depression, examples of pluralistically oriented research practices, and analysis of a pluralistic conceptualisation of the nature of evidence. Implications of a pluralistic perspective for research training and practice are discussed. Pluralistic inquiry that emphasises dialogue, collaboration, epistemic justice and the co-existence of multiple truths, creates opportunities for individuals, families and communities from a wide range of backgrounds to co-produce knowledge in ways that support their capacities for active citizenship and involvement in open democratic decision-making. To fulfil these possibilities, it is necessary for psychotherapy research to be oriented towards social goals that are sufficiently relevant to both researchers and co-participants to harness their passion and work together for a common good.

19.
Psychotherapy (Chic) ; 57(4): 562-573, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-31120268

RESUMEN

Performance accountability-also frequently referred to as quality improvement in the fields of medicine and public policy-is under growing scrutiny in mental and behavioral health care. As one high-profile example, psychologists and other mental health providers will be deemed "eligible clinicians" under the 2015 Medicare Access and Children's Health Insurance Program Reauthorization Act starting in 2019. This will incentivize psychologists to track their Medicare patients' clinical outcomes and report them in data registries, and those who do not will suffer a reimbursement penalty. However, many psychologists are not aware of these developments or prepared for this change. The goal of this article is to provide information to psychologists about quality improvement and clinical data registries from four distinct, though overlapping, vantage points: professional governance, quantitative research, qualitative research, and clinical practice. We review recent regulations and research in this area, with an emphasis on exploring both the potential benefits and challenges of quality improvement. We conclude by providing recommendations for the field of psychology. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Asunto(s)
Psicología , Mejoramiento de la Calidad , Sistema de Registros , Humanos , Medicare , Estados Unidos
20.
Nanoscale ; 11(13): 6182-6191, 2019 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-30874273

RESUMEN

Inorganic lead halide perovskite CsPbX3 (X = Cl, Br, or I) nanocrystals are promising candidate materials for light-emitting devices and optoelectronics. Mn-Doped CsPbX3 is of particular interest, as the Mn-doping introduces an additional emission band, making this material a promising white-light emitter. In this study, Mn-doped CsPb(Br/Cl)3 nanocrystals are prepared at room-temperature and ambient pressure. The chemical environment of Mn, and the luminescence of these nanocrystals are analyzed in detail using X-ray diffraction (XRD), extended X-ray absorption fine structure (EXAFS), X-ray absorption near-edge structure (XANES) and X-ray excited optical luminescence (XEOL). Although the introduction of Mn does not alter the long-range order of the CsPbX3 crystal, it leads to a local lattice contraction with the bond length of Mn-X much shorter than Pb-X. We also find excitation energy-dependence in both the intensity and wavelength of the perovskite excitonic emission band, while only in intensity of the Mn emission band. Detailed fitting of the XEOL reveals that the perovskite emission band is dual-channel, and it is the excitation energy-dependent intensity variation of these two channels that drives the observed red-shift of the combined emission band. Our findings also confirm that the Mn emission band is driven by exciton-Mn energy transfer and clarify the Mn chemical environment and the luminescence mechanism in Mn-doped CsPb(Br/Cl)3 nanocrystals.

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