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Lead Mixed Halide Perovskites (LMHPs), CsPbBrI2, have attracted significant interest as promising candidates for wide bandgap absorber layers in tandem solar cells due to their relative stability and red-light emission with a bandgap â¼1.7 eV. However, these materials segregate into Br-rich and I-rich domains upon continuous illumination, affecting their optical properties and compromising the operational stability of devices. Herein, we track the microscopic processes occurring during halide segregation by using combined spectroscopic measurements at room and cryogenic temperatures. We also evaluate a passivation strategy to mitigate the halide migration of Br/I ions in the films by overcoating with cyclic olefin copolymer (COC). Our results explain the correlation between grain size, intensity dependencies, phase segregation, activation energy barrier, and their influence on photoinduced carrier lifetimes. Importantly, COC treatment increases the lifetime charge carriers in mixed halide thin films, improving efficient charge transport in perovskite solar cell applications.
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Ultranarrow bandwidth single-photon sources operating at room-temperature are of vital importance for viable optical quantum technologies at scale, including quantum key distribution, cloud-based quantum information processing networks, and quantum metrology. Here we show a room-temperature ultranarrow bandwidth single-photon source generating single-mode photons at a rate of 5 MHz based on an inorganic CsPbI3 perovskite quantum dot embedded in a tunable open-access optical microcavity. When coupled to an optical cavity mode, the quantum dot room-temperature emission becomes single-mode, and the spectrum narrows down to just â¼1 nm. The low numerical aperture of the optical cavities enables efficient collection of high-purity single-mode single-photon emission at room-temperature, offering promising performance for photonic and quantum technology applications. We measure 94% pure single-photon emission in a single-mode under pulsed and continuous-wave (CW) excitation.
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CONTEXT: Exploring sports-related musculoskeletal injuries and treatment characteristics in middle school sports may help inform patient care decisions such as appropriate medical coverage. OBJECTIVE: To describe injury and treatment characteristics of middle school-aged athletes receiving care from athletic trainers within the Athletic Training Practice-Based Research Network (AT-PBRN). DESIGN: Descriptive study. SETTING: Middle school. PATIENT OR OTHER PARTICIPANTS: Middle school-aged athletes (n=1,011; male=503, female=506) with sports-related musculoskeletal injuries. MAIN OUTCOME MEASURE(S): Electronic patient records were analyzed from the AT-PBRN from 59 athletic trainers across 14 states between 2010-2022. Summary statistics (frequency, percentages, median, interquartile ranges [IQR]) were used to describe injury (age at injury, sex, sport, body part, diagnosis) and treatment characteristics (type of treatment, number of visits, number of procedures per visit). RESULTS: Football (17.7%, n=179), basketball (17.6%, n=178), and soccer (14.9%, n=151) reported the highest number of injuries. Ankle (17.2%, n=174), knee (16.5%, n=167), and head (14.1%, n=143) were the most common injury locations. Concussion (13.0%, n=131), ankle strain/sprain (12.4%, n=125), and thigh/hip/groin sprain/strain (11.1%, n=112) were the most reported diagnoses. Therapeutic exercise or activities (25.6%, n=1068), athletic trainer evaluation or re-evaluation (22.9%, n=957) and hot/cold packs (18.4%, n=766) were the most common services with a median of 2 visits (IQR=1-4) and 2 procedures (IQR=1-2) per visit. CONCLUSIONS: Football, basketball, and soccer reported the most musculoskeletal injuries for middle school-aged athletes. Concussions were the most frequent diagnosis, followed by ankle sprains/strains. Our findings are similar to prior investigations at high school and collegiate levels. Treatments at the middle school level were also similar to those that have been previously reported at the high school level with therapeutic exercise/activity, athletic trainer evaluation or re-evaluation, and hot/cold packs being the most common treatments. This information may be useful for informing patient care decisions at the middle-school level.
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Team-based care approaches are effective at improving hypertension control and have been used in clinical practice to improve hypertension outcomes. This study implemented and evaluated the Hypertension Management Program (HMP), which was originally developed in a high-resource health setting, in a health system with fewer resources and a patient population disproportionately affected by hypertension. Our objectives were to describe how a health system could adapt HMP to meet their needs and calculate total program costs. HMP uses a team-based, patient-centered approach involving clinical pharmacists who contribute to managing patients who have hypertension and ultimately preventing premature death due to uncontrolled hypertension. HMP has 10 components (e.g., EHR patient registries and outreach lists, no copayment walk-in blood pressure checks). Our project involved implementing the key components of HMP in a federally qualified health center (FQHC) in South Carolina. Adaptations from the key components of HMP were made to fit the participants' settings. A mixed-methods evaluation assessed implementation processes, program costs, and implementation facilitators and barriers. From September 2018 to December 2019, clinical pharmacists conducted 758 hypertension management visits (HMVs) with 316 patients with hypertension. Total program costs for HMP were $325,532 overall and $16,277 per month. Monthly cost per patient was $3.62. The high engagement among clinical pharmacists, along with provider engagements, followed up by the subsequent referral of patients to HMP, facilitated the implementation process. Staff members observed improvements in hypertension control, which increased participation buy-in. Barriers included staff turnover, the perception among some providers that HMP took too much time, as well as perception of HMP as a pharmacy-specific initiative. A team-based, patient-centered approach to hypertension management can be adapted for FQHCs or similar settings that serve patient populations disproportionately affected by hypertension.
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OBJECTIVES: Developing an expanded representation of the total testing process that includes contemporary elements of laboratory practice can be useful to understanding and optimizing testing workflows across clinical laboratory and patient care settings. METHODS: Published literature and meeting reports were used by the coauthors to inform the development of the expanded representation of the total testing process and relevant examples describing its uses. RESULTS: A visual representation of the total testing process was developed and contextualized to patient care scenarios using a number of examples covering the detection of blood culture contamination, use of next-generation sequencing, and pharmacogenetic testing. CONCLUSIONS: The expanded representation of the total testing process can serve as a model and framework to document and improve the use of clinical testing within the broader context of health care delivery. This representation recognizes increased engagement among clinical laboratory professionals with patients and other health care providers as essential to making informed decisions. The increasing use of data is highlighted as important to ensuring quality, appropriate test utilization, and sustaining an efficient workflow across clinical laboratory and patient care settings. Maintaining a properly resourced and competent workforce is also featured as an essential component to the testing process.
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Servicios de Laboratorio Clínico , Laboratorios Clínicos , Humanos , Atención a la SaludRESUMEN
High-grade serous ovarian cancer (HGSC) is frequently characterized by homologous recombination (HR) DNA repair deficiency and, while most such tumors are sensitive to initial treatment, acquired resistance is common. We undertook a multiomics approach to interrogate molecular diversity in end-stage disease, using multiple autopsy samples collected from 15 women with HR-deficient HGSC. Patients had polyclonal disease, and several resistance mechanisms were identified within most patients, including reversion mutations and HR restoration by other means. We also observed frequent whole-genome duplication and global changes in immune composition with evidence of immune escape. This analysis highlights diverse evolutionary changes within HGSC that evade therapy and ultimately overwhelm individual patients.
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Cistadenocarcinoma Seroso , Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/genética , Multiómica , Carcinoma Epitelial de Ovario , Recombinación Homóloga/genética , Cistadenocarcinoma Seroso/genéticaRESUMEN
CONTEXT: Limited evidence exists regarding the assessment of single-item patient-reported outcomes when patients are medically cleared to return to sport after a lateral ankle sprain (LAS) injury. OBJECTIVE: To evaluate self-reports of improvement in health status, pain, function, and disability at return to sport after an LAS. DESIGN: Descriptive study. SETTING: Sixty-nine athletic training facilities across 24 states. PATIENTS OR OTHER PARTICIPANTS: A total of 637 patients (males = 53.2%) who were diagnosed with an LAS, restricted from sport after injury, and subsequently medically cleared to return to sport within 60 days were included. MAIN OUTCOME MEASURE(S): Descriptive statistics were used to summarize scores for health status (Global Rating of Change), pain (Numeric Pain Rating Scale), function (Global Rating of Function), and disability (Global Rating of Disability). Mann-Whitney U tests were used to compare score differences between sexes. A Kaplan-Meier analysis was performed to provide a visual depiction of sex differences in the time to return to sport. RESULTS: Most patients sustained an LAS injury while participating in basketball, football, or soccer and were cleared to return to sport 8 days after injury. More than two-thirds of patients reported a meaningful improvement in health status between the time of injury and return to sport. However, many noted deficits related to pain (65.1%), function (86.2%), or disability (35.8%) at return to sport. No differences were seen between males and females for pain (P = .90), function (P = .68), change in health status (P = .45), or disability (P = .21) at return to sport, although males returned to sport slightly sooner than females (P = .025). CONCLUSIONS: Despite self-perceived improvements in health status since the time of injury, patients typically returned to sport with deficits in pain, function, and disability after an LAS. Patients may be returning to unrestricted sport participation before they feel their bodies have fully recovered from the injury.
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Traumatismos del Tobillo , Traumatismos en Atletas , Baloncesto , Esguinces y Distensiones , Humanos , Masculino , Femenino , Traumatismos en Atletas/terapia , Volver al Deporte , Esguinces y Distensiones/terapia , Traumatismos del Tobillo/terapia , Medición de Resultados Informados por el Paciente , DolorRESUMEN
CONTEXT: Ankle sprains are common during sport participation and associated with long-term deficits in self-report of function. However, little is known of short-term changes in self-report of function following injury. The authors aimed to assess statistical and clinically meaningful changes in self-report of function, as measured by the Foot and Ankle Ability Measure (FAAM), during the first 2 weeks after an ankle sprain injury. DESIGN: A retrospective analysis of electronic medical records. METHODS: Eighty-eight patients, who were diagnosed with an ankle sprain injury by an athletic trainer, received usual care from an athletic trainer, and completed the FAAM during treatment at weeks 1 and 2 postinjury. The authors calculated the percentage of patients who reported clinically meaningful changes and used Wilcoxon signed-rank tests to compare differences in FAAM scores between time points. RESULTS: Between weeks 1 and 2, significant differences were noted for the FAAM Activities of Daily Living (FAAM-ADL) (P < .001) and FAAM Sport (FAAM-Sport) (P < .001). At the patient level, 86.5% (64/74) and 85.2% (69/81) of patients reported changes that exceeded the minimal clinically important difference value for the FAAM-ADL and FAAM-Sport, respectively, between weeks 1 and 2. At week 2, 31.8% (28/88) and 47.7% (42/88) of patients reported a score below 90% on the FAAM-ADL and below 80% on the FAAM-Sport subscale, respectively. Also, 36.4% (32/88) and 25.0% (22/88) of patients reported a score of 100% on the FAAM-ADL and FAAM-Sport subscales, respectively, at week 2. CONCLUSIONS: Patients report statistically significant and meaningful improvements in self-report of function during the first 2 weeks following ankle sprain injury. However, almost half of patients still report deficits in sport function at 2 weeks postinjury. Patient-reported outcome measures such as the FAAM, can help capture the patient's perception of function and inform patient care decisions. Research efforts should explore individual response patterns to treatment.
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Traumatismos del Tobillo , Deportes , Esguinces y Distensiones , Humanos , Autoinforme , Actividades Cotidianas , Estudios Retrospectivos , Articulación del Tobillo , Traumatismos del Tobillo/terapia , Esguinces y Distensiones/terapiaRESUMEN
Recently, there has been an emphasis on collecting large datasets in the field of sports medicine. While there have been great advances in areas of sport performance and sport epidemiology, there have been fewer efforts dedicated to understanding the effectiveness and impact of athletic healthcare, including injury prevention programs and rehabilitation interventions provided at the point-of-care. In 2009, the Athletic Training Practice-Based Research Network (AT-PBRN) was launched to address this need, with the mission of improving the quality of care provided by athletic trainers. Unlike other research efforts in sports and medicine, such as sport epidemiology, there are fewer methodological best practices specifically related to clinical data in athletic healthcare. As a result, the AT-PBRN has encountered several methodological challenges during its tenure and has established guidelines based on various sources within the fields of sports and medicine to address these challenges. Therefore, the purpose of this perspective is to identify the challenges and describe strategies to address these challenges related to characterizing athletic healthcare using a large database. Specifically, challenges related to data entry (data quality and reliability) and data extraction and processing (data variability and missing data) will be discussed. Sharing challenges and perspectives on solutions for collecting and reporting on athletic healthcare data may facilitate a greater consistency in the approach used to collect, analyze, and report on clinical data in athletic healthcare, with the goal of improving patient outcomes and the quality of care provided by athletic trainers.
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BACKGROUND: Evaluating adolescent athletes' perceived health status after a sport-related injury can provide important direction for health promotion strategies and preparation for a successful return to play. Furthermore, comparing specific injury types regarding their impact on athletes' perspectives of their global and domain-specific health perceptions allows for a more detailed understanding of an athlete's experience while also providing avenues for targeted treatment strategies. PURPOSE: To compare health-related quality of life (HRQOL) between high school athletes who had sustained either a concussion or an acute ankle injury and compare how these injury types related to their global and domain-specific HRQOL across recovery. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Electronic medical records created by athletic trainers working in 32 high school facilities were examined, and records from 1749 patients who sustained either a sport-related concussion (n = 862) or ankle sprain (n = 887) were screened for inclusion. HRQOL was assessed by self-reported scores on the Pediatric Quality of Life Inventory (PedsQL) at 2 time points after injury (T1 = 0-2 days; T2 = 11-29 days). A 2-way group by time analysis of variance was conducted to examine differences in trajectories and disrupted areas of HRQOL. RESULTS: Overall, 85 patient cases (46 concussion, 39 ankle sprain) fit the inclusion criteria. Each injury group exhibited improved global and domain-specific PedsQL scores between their 2 measured time points (P < .05), indicating recovery. However, domain-specific comparisons revealed that at T2, patients who had sustained an ankle sprain reported significantly lower PedsQL physical functioning scores (78.3 ± 19.3 vs 86.2 ± 15.7 for concussion; P = .005), whereas patients who had sustained a concussion reported lower scores related to their school functioning (80.0 ± 20.0 vs 90.8 ± 12.7 for ankle sprain; P = .006). CONCLUSION: The study results indicated that in high school athletes, the trajectories and disrupted areas of HRQOL stemming from a sport-related injury may be influenced differentially when comparing concussions with ankle sprains.
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Colloidally grown nanosized semiconductors yield extremely high-quality optoelectronic materials. Many examples have pointed to near perfect photoluminescence quantum yields, allowing for technology-leading materials such as high purity color centers in display technology. Furthermore, because of high chemical yield, and improved understanding of the surfaces, these materials, particularly colloidal quantum dots (QDs) can also be ideal candidates for other optoelectronic applications. Given the urgent necessity toward carbon neutrality, electricity from solar photovoltaics will play a large role in the power generation sector. QDs are developed and shown dramatic improvements over the past 15 years as photoactive materials in photovoltaics with various innovative deposition properties which can lead to exceptionally low-cost and high-performance devices. Once the key issues related to charge transport in optically thick arrays are addressed, QD-based photovoltaic technology can become a better candidate for practical application. In this article, the authors show how the possibilities of different deposition techniques can bring QD-based solar cells to the industrial level and discuss the challenges for perovskite QD solar cells in particular, to achieve large-area fabrication for further advancing technology to solve pivotal energy and environmental issues.
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Despite a call to incorporate patient-reported outcome measures (PROMs) into all aspects of health care, little is known about which instruments are best suited for a pediatric patient population with sport-related injury. The objective of this article was to perform a systematic review of the currently available evidence to determine which PROMs were used for pediatric patients with sport-related injuries and identify the associated psychometric properties and considerations for clinical utility. We conducted a literature search for articles on PROMs used in the pediatric population through electronic databases and a manual search of reference lists and authors between from inception to 2020. Articles were grouped based on the PROM(s) included, and considerations for clinical utility and psychometric properties were extracted from each article. Thirty-nine articles were included in this review, from which 22 PROMs were identified: 12 PROMs were developed specifically for the pediatric population, 4 were modified versions of an adult scale, and 6 were adult measures used in a pediatric population. Of the PROMs included in this review, the Oxford Ankle Foot Questionnaire for Children and the Pediatric Quality of Life Inventory were the most comprehensive in their development and assessment. Several outcome measures used for pediatric patients had missing or inadequate measurement properties and considerations for clinical utility, particularly in regard to readability, responsiveness, and interpretability. Clinicians and researchers should consider a measure's feasibility, acceptability, appropriateness, and psychometric properties when selecting a PROM for use with the pediatric population.
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Medición de Resultados Informados por el Paciente , Deportes , Adulto , Niño , Humanos , Psicometría , Calidad de Vida , Encuestas y CuestionariosRESUMEN
Lymphocyte-rich classic Hodgkin lymphoma (LR-CHL) is a rare subtype of Hodgkin lymphoma. Recent technical advances have allowed for the characterization of specific cross-talk mechanisms between malignant Hodgkin Reed-Sternberg (HRS) cells and different normal immune cells in the tumor microenvironment (TME) of CHL. However, the TME of LR-CHL has not yet been characterized at single-cell resolution. Here, using single-cell RNA sequencing (scRNA-seq), we examined the immune cell profile of 8 cell suspension samples of LR-CHL in comparison to 20 samples of the mixed cellularity (MC, 9 cases) and nodular sclerosis (NS, 11 cases) subtypes of CHL, as well as 5 reactive lymph node controls. We also performed multicolor immunofluorescence (MC-IF) on tissue microarrays from the same patients and an independent validation cohort of 31 pretreatment LR-CHL samples. ScRNA-seq analysis identified a unique CD4+ helper T cell subset in LR-CHL characterized by high expression of Chemokine C-X-C motif ligand 13 (CXCL13) and PD-1. PD-1+CXCL13+ T cells were significantly enriched in LR-CHL compared to other CHL subtypes, and spatial analyses revealed that in 46% of the LR-CHL cases these cells formed rosettes surrounding HRS cells. MC-IF analysis revealed CXCR5+ normal B cells in close proximity to CXCL13+ T cells at significantly higher levels in LR-CHL. Moreover, the abundance of PD-1+CXCL13+ T cells in the TME was significantly associated with shorter progression-free survival in LR-CHL (P = 0.032). Taken together, our findings strongly suggest the pathogenic importance of the CXCL13/CXCR5 axis and PD-1+CXCL13+ T cells as a treatment target in LR-CHL.
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Linfocitos B/metabolismo , Quimiocina CXCL13/metabolismo , Enfermedad de Hodgkin/patología , Receptores CXCR5/metabolismo , Linfocitos T Colaboradores-Inductores/metabolismo , Antígeno B7-H1/metabolismo , Técnica del Anticuerpo Fluorescente , Humanos , Ganglios Linfáticos/citología , Receptor de Muerte Celular Programada 1/metabolismo , RNA-Seq , Células de Reed-Sternberg/patología , Análisis de la Célula Individual , Microambiente Tumoral/inmunologíaRESUMEN
The ligand-nanocrystal boundaries of colloidal quantum dots (QDs) mediate the primary energy and electron transfer processes that underpin photochemical and photocatalytic transformations at their surfaces. We use mid-infrared transient absorption spectroscopy to reveal the influence that ligand structure and bonding to nanocrystal surfaces have on the changes of the excited state surface chemistry of this boundary in PbS QDs and the corresponding impact on charge transfer processes between nanocrystals. We demonstrate that oleate ligands undergo marked changes in their bonding to surfaces in the excitonic excited states of the nanocrystals, indicating that oleate passivated PbS surfaces undergo significant structural changes following photoexcitation. These changes can impact the surface mobility of the ligands and the ability of redox shuttles to approach the nanocrystal surfaces to undergo charge transfer in photocatalytic reactions. In contrast, markedly different transient vibrational features are observed in iodide/mercaptoproprionic acid passivated PbS QD films that result from charge transfer between neighboring nanocrystals and localization of holes at the nanocrystal surfaces near MPA ligands. This ability to distinguish the influence that excitonic excited states vs charge transfer processes have on the surface chemistry of the ligand-nanocrystal boundary lays the groundwork for exploration of how this boundary can be understood and controlled for the design of nanocrystalline materials tailored for specific applications in solar energy harvesting and photocatalytic reactions.
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CONTEXT: Knee injuries are common during sport participation. However, little is known about the overall management and estimated direct costs of care associated with these injuries when under the care of athletic trainers. OBJECTIVE: To describe the treatment characteristics and direct costs of care for athletic training services provided for patients with knee injuries. DESIGN: Descriptive study. SETTING: Ninety-five athletic training facilities across 24 states. PATIENTS OR OTHER PARTICIPANTS: A total of 117 athletic trainers (females = 56.4%, age = 29.4 ± 8.7 years, years certified = 4.7 ± 6.0, years employed at site = 1.6 ± 4.1). MAIN OUTCOME MEASURE(S): Complete patient cases were identified using International Classification of Disease-10 diagnostic codes between 2009 and 2020. Summary statistics were calculated for patient demographics, treatment characteristics, and direct costs of care. Treatment characteristics included the type of athletic training service, duration, amount (eg, number of visits), and direct costs of care. RESULTS: A total of 441 patient cases were included. The most common injuries reported were cruciate ligament sprain (18.1%, n = 80), medial collateral ligament sprain (15.4%, n = 68), and knee pain (14.1%, n = 62). Injuries occurred most frequently during football (35.4%, n = 156), basketball (14.7%, n = 65), and soccer (12.7%, n = 56). A total of 8484 athletic training services were recorded over 4254 visits, with therapeutic exercise (29.8%, n = 2530), hot or cold pack (25.8%, n = 2189), and therapeutic activities (11.2%, n = 954) being the most frequently reported services. The median duration of care was 23 days and number of visits was 8. The median total cost of care was $564 per injury and $73 per visit. CONCLUSIONS: Patients with knee injuries demonstrated greater time loss than those with other lower extremity injuries. Thus, it is unsurprising that knee injuries were associated with a longer duration and higher cost of care than other lower extremity injuries such as ankle sprains. Future researchers should examine the effectiveness of common treatment strategies and aim to identify treatments that can reduce costs and improve patient outcomes.
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Traumatismos en Atletas , Costos de la Atención en Salud , Traumatismos de la Rodilla , Adulto , Atletas , Traumatismos en Atletas/economía , Traumatismos en Atletas/terapia , Femenino , Humanos , Traumatismos de la Rodilla/economía , Traumatismos de la Rodilla/terapia , Masculino , Instituciones Académicas , Adulto JovenRESUMEN
CONTEXT: Cross-country is a popular sport activity, particularly in adolescent populations. Although epidemiologic investigations have provided insight into patient and injury characteristics associated with running injuries, little is known about how these injuries are managed at the point of care. OBJECTIVE: To describe injury and treatment characteristics of injuries sustained during cross-country. DESIGN: Cross-sectional study. SETTING: High school athletic training clinics within the Athletic Training Practice-Based Research Network. PATIENTS OR OTHER PARTICIPANTS: Patient cases were included if the patient was diagnosed with an injury that occurred during interscholastic cross-country participation. All patients received usual care by an athletic trainer. MAIN OUTCOME MEASURE(S): We used summary statistics to describe injury (sex, age, participation level, time of injury, mechanism of injury, body part, injury type, diagnosis) and treatment (type, amount, duration, number of services) characteristics. RESULTS: Most cross-country injuries occurred to the lower extremity and were musculotendinous or ligamentous in nature. The most common injury types were sprain/strain (43.8%), tendinopathy (18.5%), and general pain (9.5%). Injured body parts and diagnoses were typically similar between sexes. The most frequently used treatment was therapeutic exercises or activities (28.7%), and patients received an average of 7.4 ± 17.4 total athletic training services during 5.5 ± 15.1 episodes of care over 27.8 ± 87.5 days. CONCLUSIONS: Adolescent cross-country student-athletes frequently sustained non-time-loss injuries that required up to 1 month of treatment and management. These findings will generate awareness surrounding the role of athletic trainers in providing care for cross-country athletes.
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Traumatismos en Atletas/epidemiología , Carrera/lesiones , Adolescente , Adulto , Atletas/estadística & datos numéricos , Traumatismos en Atletas/diagnóstico , Estudios Transversales , Terapia por Ejercicio , Femenino , Humanos , Extremidad Inferior/lesiones , Masculino , Instituciones Académicas/estadística & datos numéricos , Esguinces y Distensiones , EstudiantesRESUMEN
Light-emitting diodes (LEDs) made from metal halide perovskites have demonstrated external electroluminescent quantum efficiencies (EQEEL) in excess of 20%. However, their poor operational stability, resulting in lifetimes of only tens to hundreds of hours, needs to be dramatically improved prior to commercial use. There is little consensus in the community upon which factors limit the stability of these devices. Here, we investigate the role played by ammonium cations on the operational stability. We vary the amount of phenylethylammonium bromide, a widely used alkylammonium salt, that we add to a precursor solution of CsPbBr3 and track changes in stability and EQEEL. We find that while phenylethylammonium bromide is beneficial in achieving high efficiency, it is highly detrimental to operational stability. We investigate material properties and electronic characteristics before and after degradation and find that both a reduction in the radiative efficiency of the emitter and significant changes in current-voltage characteristics explain the orders of magnitude drop in the EQEEL, which we attribute to increased ionic mobility. Our results suggest that engineering new contacts and further investigation into materials with lower ionic mobility should yield much improved stability of perovskite LEDs.
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The ligand shell around colloidal quantum dots mediates the electron and energy transfer processes that underpin their use in optoelectronic and photocatalytic applications. Here, we show that the surface chemistry of carboxylate anchoring groups of oleate ligands passivating PbS quantum dots undergoes significant changes when the quantum dots are excited to their excitonic states. We directly probe the changes of surface chemistry using time-resolved mid-infrared spectroscopy that records the evolution of the vibrational frequencies of carboxylate groups following excitation of the electronic states. The data reveal a reduction of the Pb-O coordination of carboxylate anchoring groups to lead atoms at the quantum dot surfaces. The dynamic surface chemistry of the ligands may increase their surface mobility in the excited state and enhance the ability of molecular species to penetrate the ligand shell to undergo energy and charge transfer processes that depend sensitively on distance.
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Clinical Scenario: Low back pain is widely prevalent in the general population as well as in athletes. Therapeutic exercise is a low-risk and effective treatment option for chronic pain that can be utilized by all rehabilitation clinicians. However, therapeutic exercise alone does not address the psychosocial aspects that are associated with chronic low back pain. Pain education is the umbrella term utilized to encompass any type of education to the patient about their chronic pain. Therapeutic exercise in combination with pain education may allow for more well-rounded and effective treatment for patients with chronic nonspecific low back pain (NS-LBP). Clinical Question: Does pain education combined with therapeutic exercise, compared with therapeutic exercise alone, improve patient pain in adults with chronic NS-LBP over a 2- to 3-month treatment period? Summary of Key Findings: A thorough literature review yielded 8 studies potentially relevant to the clinical question, and 3 studies that met the inclusion criteria were included. The 3 studies included reports that exercise therapy reduced symptoms. Two of the 3 included studies support the claim that exercise therapy reduces the symptoms of chronic NS-LBP when combined with pain education, whereas one study found no difference between pain education with therapeutic exercise. Clinical Bottom Line: There is moderate evidence to support the use of pain education along with therapeutic exercise when attempting to reduce symptoms of pain and disability in patients with chronic NS-LBP. Educational interventions should be created to educate patients about the foundation of pain, and pain education should be implemented as a part of the clinician's strategy for the rehabilitation of patients with chronic NS-LBP. Strength of Recommendation: Grade B evidence exists to support the use of patient education with therapeutic exercise for decreasing pain in patients with chronic NS-LBP.