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1.
Nanotechnology ; 35(39)2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38955146

RESUMEN

We present the electrical characterization of wafer-scale graphene devices fabricated with an industrially-relevant, contact-first integration scheme combined with Al2O3encapsulation via atomic layer deposition. All the devices show a statistically significant reduction in the Dirac point position,Vcnp, from around +47 V to between -5 and 5 V (on 285 nm SiO2), while maintaining the mobility values. The data and methods presented are relevant for further integration of graphene devices, specifically sensors, at the back-end-of-line of a standard CMOS flow.

2.
Biol Lett ; 19(3): 20220546, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36946131

RESUMEN

Dried plant specimens stored in herbaria are an untapped treasure chest of information on environmental conditions, plant evolution and change over many hundreds of years. Owing to their delicate nature and irreplaceability, there is limited access for analysis to these sensitive samples, particularly where chemical data are obtained using destructive techniques. Fourier transform infrared (FTIR) spectroscopy is a chemical analysis technique which can be applied non-destructively to understand chemical bonding information and, therefore, functional groups within the sample. This provides the potential for understanding geographical, spatial and species-specific variation in plant biochemistry. Here, we demonstrate the use of mid-FTIR microspectroscopy for the chemical analysis of Drosera rotundifolia herbarium specimens, which were collected 100 years apart from different locations. Principal component and hierarchical clustering analysis enabled differentiation between three main regions on the plant (lamina, tentacle stalk and tentacle head), and between the different specimens. Lipids and protein spectral regions were particularly sensitive differentiators of plant tissues. Differences between the different sets of specimens were smaller. This study demonstrates that relevant information can be extracted from herbarium specimens using FTIR, with little impact on the specimens. FTIR, therefore, has the potential to be a powerful tool to unlock historic information within herbaria.


Asunto(s)
Plantas , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Análisis por Conglomerados , Análisis de Componente Principal
3.
Antimicrob Agents Chemother ; 66(4): e0241421, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35341315

RESUMEN

Klebsiella pneumoniae carbapenemases (KPC-2 and KPC-3) present a global clinical threat, as these ß-lactamases confer resistance to carbapenems and oxyimino-cephalosporins. Recent clinically identified KPC variants with substitutions at Ambler position D179, located in the Ω loop, are resistant to the ß-lactam/ß-lactamase inhibitor combination ceftazidime-avibactam, but susceptible to meropenem-vaborbactam. To gain insights into ceftazidime-avibactam resistance conferred by D179N/Y variants of KPC-2, crystal structures of these variants were determined. The D179N KPC-2 structure revealed that the change of the carboxyl to an amide moiety at position 179 disrupted the salt bridge with R164 present in wild-type KPC-2. Additional interactions were disrupted in the Ω loop, causing a decrease in the melting temperature. Shifts originating from N179 were also transmitted toward the active site, including ∼1-Å shifts of the deacylation water and interacting residue N170. The structure of the D179Y KPC-2 ß-lactamase revealed more drastic changes, as this variant exhibited disorder of the Ω loop, with other flanking regions also being disordered. We postulate that the KPC-2 variants can accommodate ceftazidime because the Ω loop is displaced in D179Y or can be more readily displaced in D179N KPC-2. To understand why the ß-lactamase inhibitor vaborbactam is less affected by the D179 variants than avibactam, we determined the crystal structure of D179N KPC-2 in complex with vaborbactam, which revealed wild-type KPC-2-like vaborbactam-active site interactions. Overall, the structural results regarding KPC-2 D179 variants revealed various degrees of destabilization of the Ω loop that contribute to ceftazidime-avibactam resistance, possible substrate-assisted catalysis of ceftazidime, and meropenem and meropenem-vaborbactam susceptibility.


Asunto(s)
Ceftazidima , Inhibidores de beta-Lactamasas , Antibacterianos/farmacología , Compuestos de Azabiciclo/farmacología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Ceftazidima/farmacología , Combinación de Medicamentos , Klebsiella pneumoniae/genética , Meropenem/farmacología , Pruebas de Sensibilidad Microbiana , Inhibidores de beta-Lactamasas/farmacología , beta-Lactamasas/genética
4.
J Synchrotron Radiat ; 29(Pt 4): 1074-1084, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35787575

RESUMEN

In this work, a new image guidance system and protocols for delivering image-guided radiotherapy (IGRT) on the Imaging and Medical Beamline (IMBL) at the ANSTO Australian Synchrotron are introduced. The image guidance methods used and the resulting accuracy of tumour alignment in in vivo experiments are often under-reported. Image guidance tasks are often complex, time-consuming and prone to errors. If unchecked, they may result in potential mis-treatments. We introduce SyncMRT, a software package that provides a simple, image guidance tool-kit for aligning samples to the synchrotron beam. We have demonstrated sub-millimetre alignment using SyncMRT and the small-animal irradiation platform (the DynamicMRT system) on the IMBL. SyncMRT has become the standard for carrying out IGRT treatments on the IMBL and has been used in all pre-clinical radiotherapy experiments since 2017. Further, we introduce two quality assurance (QA) protocols to synchrotron radiotherapy on the IMBL: the Winston-Lutz test and hidden target test. It is shown that the presented QA tests are appropriate for picking up geometrical setup errors and assessing the end-to-end accuracy of the image guidance process. Together, these tools make image guidance easier and provide a mechanism for reporting the geometric accuracy of synchrotron-based IGRT treatments. Importantly, this work is scalable to other delivery systems, and is in continual development to support the upcoming veterinary radiotherapy trials on the IMBL.


Asunto(s)
Radioterapia Guiada por Imagen , Animales , Australia , Radioterapia Guiada por Imagen/métodos , Sincrotrones
5.
Proc Natl Acad Sci U S A ; 116(52): 26474-26483, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31843883

RESUMEN

Efforts to confront the challenges of environmental change and uncertainty include attempts to adaptively manage social-ecological systems. However, critical questions remain about whether adaptive management can lead to sustainable outcomes for both ecosystems and society. Here, we make a contribution to these efforts by presenting a 16-y analysis of ecological outcomes and perceived livelihood impacts from adaptive coral reef management in Papua New Guinea. The adaptive management system we studied was a customary rotational fisheries closure system (akin to fallow agriculture), which helped to increase the biomass of reef fish and make fish less wary (more catchable) relative to openly fished areas. However, over time the amount of fish in openly fished reefs slowly declined. We found that, overall, resource users tended to have positive perceptions about this system, but there were negative perceptions when fishing was being prohibited. We also highlight some of the key traits of this adaptive management system, including 1) strong social cohesion, whereby leaders played a critical role in knowledge exchange; 2) high levels of compliance, which was facilitated via a "carrot-and-stick" approach that publicly rewarded good behavior and punished deviant behavior; and 3) high levels of participation by community actors.

6.
Adv Physiol Educ ; 46(2): 268-278, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35175827

RESUMEN

Bioethics is an important aspect of understanding the relationship between science and society, but studies have not yet examined undergraduate student experiences and comfort in bioethics courses. In this study, we investigated undergraduate bioethics students' support of and comfort when learning three controversial bioethics topics: gene editing, abortion, and physician-assisted suicide (PAS). Furthermore, student identity has been shown to influence how students perceive and learn about controversial topics at the intersection of science and society. So, we explored how students' religious affiliation, gender, or political affiliation was associated with their support of and comfort when learning about gene editing, abortion, and PAS. We found that most students entered bioethics with moderated viewpoints on controversial topics but that there were differences in students' tendency to support each topic based on their gender, religion, and political affiliation. We also saw differences in student comfort levels based on identity: women reported lower comfort than men when learning about gene editing, religious students were less comfortable than nonreligious students when learning about abortion and PAS, and nonliberal students were less comfortable than liberal students when learning about abortion. Students cited that the controversy surrounding these topics and a personal hesitancy to discuss them caused discomfort. These findings indicate that identity impacts comfort and support in a way similar to that previously shown in the public. Thus, it may be important for instructors to consider student identity when teaching bioethics topics to maximize student comfort, ultimately encouraging thoughtful consideration and engagement with these topics.


Asunto(s)
Bioética , Bioética/educación , Femenino , Identidad de Género , Humanos , Aprendizaje , Masculino , Estudiantes
7.
Br J Dermatol ; 185(4): 825-835, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33829489

RESUMEN

BACKGROUND: The effectiveness and cost-effectiveness of biologic therapies for psoriasis are significantly compromised by variable treatment responses. Thus, more precise management of psoriasis is needed. OBJECTIVES: To identify subgroups of patients with psoriasis treated with biologic therapies, based on changes in their disease activity over time, that may better inform patient management. METHODS: We applied latent class mixed modelling to identify trajectory-based patient subgroups from longitudinal, routine clinical data on disease severity, as measured by the Psoriasis Area and Severity Index (PASI), from 3546 patients in the British Association of Dermatologists Biologics and Immunomodulators Register, as well as in an independent cohort of 2889 patients pooled across four clinical trials. RESULTS: We discovered four discrete classes of global response trajectories, each characterized in terms of time to response, size of effect and relapse. Each class was associated with differing clinical characteristics, e.g. body mass index, baseline PASI and prevalence of different manifestations. The results were verified in a second cohort of clinical trial participants, where similar trajectories following the initiation of biologic therapy were identified. Further, we found differential associations of the genetic marker HLA-C*06:02 between our registry-identified trajectories. CONCLUSIONS: These subgroups, defined by change in disease over time, may be indicative of distinct endotypes driven by different biological mechanisms and may help inform the management of patients with psoriasis. Future work will aim to further delineate these mechanisms by extensively characterizing the subgroups with additional molecular and pharmacological data.


Asunto(s)
Productos Biológicos , Psoriasis , Factores Biológicos/uso terapéutico , Productos Biológicos/uso terapéutico , Terapia Biológica , Ensayos Clínicos como Asunto , Humanos , Factores Inmunológicos , Psoriasis/tratamiento farmacológico , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
8.
Conserv Biol ; 34(3): 733-742, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31943349

RESUMEN

Attempts to better understand the social context in which conservation and environmental decisions are made has led to increased interest in human social networks. To improve the use of social-network analysis in conservation, we reviewed recent studies in the literature in which such methods were applied. In our review, we looked for problems in research design and analysis that limit the utility of network analysis. Nineteen of 55 articles published from January 2016 to June 2019 exhibited at least 1 of the following problems: application of analytical methods inadequate or sensitive to incomplete network data; application of statistical approaches that ignore dependency in the network; or lack of connection between the theoretical base, research question, and choice of analytical techniques. By drawing attention to these specific areas of concern and highlighting research frontiers and challenges, including causality, network dynamics, and new approaches, we responded to calls for increasing the rigorous application of social science in conservation.


Consideraciones y Retos Importantes en la Aplicación de la Investigación por medio de Redes Sociales para la Toma de Decisiones Ambientales Resumen Los intentos por tener un mejor entendimiento del contexto social en el que se toman las decisiones ambientales y de conservación han derivado en un incremento en el interés por las redes sociales humanas. Para mejorar el uso del análisis de redes sociales en la conservación, buscamos en la literatura los estudios recientes que hayan aplicado dichos métodos y los sometimos a una revisión. En esta revisión, examinamos los problemas en el diseño de la investigación y del análisis que limitan la utilidad del análisis de redes. Diecinueve de los 55 artículos publicados entre enero 2016 y junio 2019 exhibieron al menos uno de los siguientes problemas: aplicación de métodos analíticos inadecuados o sensibles a la información incompleta sobre las redes; aplicación de estrategias estadísticas que ignoran la dependencia en la red; o falta de conexión entre la base teórica, la pregunta de investigación y la selección de técnica analítica. Al llamar la atención hacia estas áreas específicas de interés y resaltar las fronteras y retos de la investigación, incluyendo la causalidad, las dinámicas de redes y las estrategias nuevas, respondimos a la necesidad de incrementar la aplicación rigurosa de las ciencias sociales en la conservación.


Asunto(s)
Conservación de los Recursos Naturales , Ciencias Sociales , Toma de Decisiones , Humanos , Organizaciones , Medio Social
9.
Sex Health ; 17(4): 392-394, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32829744

RESUMEN

Willingness to self-collect vaginal swabs at a pharmacy clinic is of interest as a venue to increase sexually transmissible infections (STIs) screening for chlamydia, gonorrhoea and trichomonas. Women self-collected vaginal swabs at the pharmacy, completed questionnaires and received STI results within 2 h. Women with STIs were offered free treatment. A total of 313 of 777 (40.3%) women consented and prevalence for any STI was 3.9%. Questionnaires demonstrated acceptability for self-collection at the pharmacy, with 63% (95% CI 57.3-68) and 32.3% (95% CI 27.4-37.8) indicating they 'strongly agreed' or 'agreed' that they felt comfortable with pharmacy collection, respectively. Self-collected vaginal swabs for STI testing for women who were at a pharmacy were feasible and acceptable to women.


Asunto(s)
Tamizaje Masivo/métodos , Aceptación de la Atención de Salud , Farmacias , Enfermedades de Transmisión Sexual/diagnóstico , Frotis Vaginal , Adulto , Estudios de Factibilidad , Femenino , Humanos , Persona de Mediana Edad , Manejo de Especímenes/métodos , Encuestas y Cuestionarios , Adulto Joven
10.
BMC Fam Pract ; 20(1): 106, 2019 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-31351467

RESUMEN

BACKGROUND: Anxiety is under-recorded and under-treated in the UK and is under-represented in research compared with depression. Detecting anxiety can be difficult because of co-existing conditions. GPs can be reluctant to medicalise anxiety symptoms and patients can be reluctant to disclose them, for a variety of reasons. This research addresses the gap in evidence of real-life consultations of patients with anxiety and explores how physical and psychological symptoms are discussed and prioritised by patients and GPs in primary care consultations. METHODS: A mixed methods study using a baseline questionnaire, video-recorded primary care consultations and interview data with patients and GPs. RESULTS: Seventeen patients with anxiety symptoms (GAD-7 score ≥ 10) completed a questionnaire, had their consultation video-recorded and took part in a semi-structured interview. Four GPs were interviewed. The main themes that emerged from GP and patients accounts as barriers and facilitators to discussing anxiety mostly mirrored each other. The GP/patient relationship and continuity of care was the main facilitator for the discussion of anxiety in the consultation. The main barriers were: attribution of or unacknowledged symptoms; co-morbidities; and time constraints. GPs overcame these barriers by making repeat appointments and employing prioritising techniques; patients by choosing an empathetic GP. CONCLUSIONS: The findings add to the evidence base concerning the management of anxiety in primary care. The findings suggest that the discussion around anxiety is a process negotiated between the patient and the GP influenced by a range of barriers and facilitators. Co-existing depression and health anxieties can mask anxiety symptoms in patients. Good practice techniques such as bringing back patients for appointments to foster continuity of care and understanding can help disclosure and detection of anxiety symptoms. Future research could investigate this longitudinally and should include a wider range of GPs practices and GPs.


Asunto(s)
Trastornos de Ansiedad/diagnóstico , Relaciones Médico-Paciente , Atención Primaria de Salud , Actitud del Personal de Salud , Femenino , Humanos , Masculino , Persona de Mediana Edad , Derivación y Consulta , Encuestas y Cuestionarios , Reino Unido , Grabación en Video
11.
BMC Psychiatry ; 17(1): 84, 2017 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-28253879

RESUMEN

BACKGROUND: Economic recessions are often accompanied by increased levels of psychological distress and suicidal behaviour in affected populations. Little is known about the experiences of people seeking help for employment, financial and benefit-related difficulties during recessions. We investigated the experiences of people struggling financially in the aftermath of the Great Recession (2008-9) - including some who had self-harmed - and of the frontline support staff providing assistance. METHODS: Interviews were conducted with three groups of people in two cities: i) people who had self-harmed due to employment, financial or benefit concerns (n = 19) ('self-harm'); ii) people who were struggling financially drawn from the community (n = 22), including one focus group) ('community'); iii) and frontline staff from voluntary and statutory sector organisations (e.g., Job Centres, Debt Advice and counselling agencies) providing support services to the groups (n = 25, including 2 focus groups) ('service providers'). Data were analysed using the constant comparison method. RESULTS: Service provision was described by people as confusing and difficult to access. The community sample reported considerably more knowledge and access to debt advice than the participants who had self-harmed - although both groups sought similar types of help. The self-harm group exhibited greater expectation that they should be self-reliant and also reported lower levels of informal networks and support from friends and relatives. They had also experienced more difficult circumstances such as benefit sanctions, and most had pre-existing mental health problems. Both self-harm and community groups indicated that practical help for debt and benefit issues would be the most useful - a view supported by service providers - and would have particularly helped those who self-harmed. CONCLUSION: Interventions to identify those in need and aid them to access practical, reliable and free advice from support agencies could help mitigate the impact on mental health of benefit, debt and employment difficulties for vulnerable sections of society.


Asunto(s)
Recesión Económica , Necesidades y Demandas de Servicios de Salud/economía , Servicios de Salud Mental/economía , Salud Mental/economía , Adulto , Consejo , Recesión Económica/tendencias , Empleo/economía , Empleo/tendencias , Inglaterra/epidemiología , Femenino , Grupos Focales , Necesidades y Demandas de Servicios de Salud/tendencias , Humanos , Masculino , Salud Mental/tendencias , Servicios de Salud Mental/tendencias , Persona de Mediana Edad , Pobreza/economía , Pobreza/psicología , Pobreza/tendencias , Conducta Autodestructiva/psicología , Adulto Joven
12.
Mol Psychiatry ; 20(7): 860-6, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25070537

RESUMEN

The aim of this paper was to investigate the association of three well-recognised dietary patterns with cognitive change over a 3-year period. Five hundred and twenty-seven healthy participants from the Australian Imaging, Biomarkers and Lifestyle study of ageing completed the Cancer Council of Victoria food frequency questionnaire at baseline and underwent a comprehensive neuropsychological assessment at baseline, 18 and 36 months follow-up. Individual neuropsychological test scores were used to construct composite scores for six cognitive domains and a global cognitive score. Based on self-reported consumption, scores for three dietary patterns, (1) Australian-style Mediterranean diet (AusMeDi), (2) western diet and (3) prudent diet were generated for each individual. Linear mixed model analyses were conducted to examine the relationship between diet scores and cognitive change in each cognitive domain and for the global score. Higher baseline adherence to the AusMeDi was associated with better performance in the executive function cognitive domain after 36 months in apolipoprotein E (APOE) ɛ4 allele carriers (P<0.01). Higher baseline western diet adherence was associated with greater cognitive decline after 36 months in the visuospatial cognitive domain in APOE ɛ4 allele non-carriers (P<0.01). All other results were not significant. Our findings in this well-characterised Australian cohort indicate that adherence to a healthy diet is important to reduce risk for cognitive decline, with the converse being true for the western diet. Executive function and visuospatial functioning appear to be particularly susceptible to the influence of diet.


Asunto(s)
Trastornos del Conocimiento/epidemiología , Dieta , Anciano , Envejecimiento/genética , Envejecimiento/psicología , Apolipoproteína E4/genética , Australia , Trastornos del Conocimiento/genética , Estudios de Cohortes , Función Ejecutiva , Femenino , Estudios de Seguimiento , Humanos , Modelos Lineales , Masculino , Pruebas Neuropsicológicas , Análisis de Componente Principal , Encuestas y Cuestionarios
13.
Eur J Vasc Endovasc Surg ; 51(4): 528-34, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26831928

RESUMEN

OBJECTIVE/BACKGROUND: The purpose of this study was to determine the preoperative variables that best predict 1-year survival following elective endovascular aneurysm repair (EVAR), a period of time that would suggest the patient had benefited from the procedure. Most EVAR survival studies focus on early and late survival; scant information is available for 1-year survival. METHODS: Data from two Australian audits of EVAR (1999-2001 and 2009-13) were combined (n = 1,647). Preoperative variables included routine demographic data, clinical health assessments, computed tomography-derived anatomical data, and all-cause mortality. Univariate and multivariate logistic regressions determined which variables best predicted 1-year survival. RESULTS: One-year survival after EVAR was 93.7% (1,544/1,647) and 30-day survival was 98.4% (1,620/1,647). Univariate analyses found that nine preoperative variables were significantly associated with 1-year survival. Five variables were included in the final multivariate model: American Society of Anesthesiologists physical status, aneurysm diameter, creatinine, respiratory assessment, and severity of iliac artery calcification (receiver-operator curve 0.717, R(2) = .117). Predicted 1-year survival ranged from 98.6% to 68.0%, based on differences in aneurysm size and patient comorbidities. CONCLUSION: Personalised 1-year survival risk enables surgeons and patients to consider seriously the risks and benefits of EVAR prior to surgery.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta Abdominal/diagnóstico , Aneurisma de la Aorta Abdominal/mortalidad , Aortografía/métodos , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/mortalidad , Comorbilidad , Bases de Datos Factuales , Procedimientos Quirúrgicos Electivos , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Australia del Sur , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
14.
Epidemiol Infect ; 144(8): 1652-60, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26808232

RESUMEN

The aim of this study was to review the current evidence regarding the persistence of Ebola virus (EBOV) in various body fluids during convalescence and discuss its implication on disease transmission and control. We conducted a systematic review and searched articles from Medline and EMBASE using key words. We included studies that examined the persistence of EBOV in various body fluids during the convalescent phase. Twelve studies examined the persistence of EBOV in body fluids, with around 800 specimens tested in total. Available evidence suggests that EBOV can persist in some body fluids after clinical recovery and clearance of virus from the blood. EBOV has been isolated from semen, aqueous humor, urine and breast milk 82, 63, 26 and 15 days after onset of illness, respectively. Viral RNA has been detectable in semen (day 272), aqueous humor (day 63), sweat (day 40), urine (day 30), vaginal secretions (day 33), conjunctival fluid (day 22), faeces (day 19) and breast milk (day 17). Given high case fatality and uncertainties around the transmission characteristics, patients should be considered potentially infectious for a period of time after immediate clinical recovery. Patients and their immediate contacts should be informed about these risks. Convalescent patients may need to abstain from sex for at least 9 months or should use condoms until their semen tests are negative. Breastfeeding should be avoided during the convalescent phase. There is a need for more research on persistence, and a uniform approach to infection control guidelines in convalescence.


Asunto(s)
Líquidos Corporales/virología , Convalecencia , Ebolavirus/aislamiento & purificación , Fiebre Hemorrágica Ebola/virología , Humanos , ARN Viral/aislamiento & purificación , Factores de Tiempo
15.
Opt Express ; 22(3): 3234-43, 2014 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-24663615

RESUMEN

We characterise THz output of lateral photo-Dember (LPD) emitters based on semi-insulating (SI), unannealed and annealed low temperature grown (LTG) GaAs. Saturation of THz pulse power with optical fluence is observed, with unannealed LTG GaAs showing highest saturation fluence at 1.1 ± 0.1 mJ cm(-2). SI-GaAs LPD emitters show a flip in signal polarity with optical fluence that is attributed to THz emission from the metal-semiconductor contact. Variation in optical polarisation affects THz pulse power that is attributed to a local optical excitation near the metal contact.

16.
Mol Psychiatry ; 18(2): 183-9, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22042228

RESUMEN

Large, rare copy number variants (CNVs) have been implicated in a variety of psychiatric disorders, but the role of CNVs in recurrent depression is unclear. We performed a genome-wide analysis of large, rare CNVs in 3106 cases of recurrent depression, 459 controls screened for lifetime-absence of psychiatric disorder and 5619 unscreened controls from phase 2 of the Wellcome Trust Case Control Consortium (WTCCC2). We compared the frequency of cases with CNVs against the frequency observed in each control group, analysing CNVs over the whole genome, genic, intergenic, intronic and exonic regions. We found that deletion CNVs were associated with recurrent depression, whereas duplications were not. The effect was significant when comparing cases with WTCCC2 controls (P=7.7 × 10(-6), odds ratio (OR) =1.25 (95% confidence interval (CI) 1.13-1.37)) and to screened controls (P=5.6 × 10(-4), OR=1.52 (95% CI 1.20-1.93). Further analysis showed that CNVs deleting protein coding regions were largely responsible for the association. Within an analysis of regions previously implicated in schizophrenia, we found an overall enrichment of CNVs in our cases when compared with screened controls (P=0.019). We observe an ordered increase of samples with deletion CNVs, with the lowest proportion seen in screened controls, the next highest in unscreened controls and the highest in cases. This may suggest that the absence of deletion CNVs, especially in genes, is associated with resilience to recurrent depression.


Asunto(s)
Variaciones en el Número de Copia de ADN/genética , Trastorno Depresivo/genética , Predisposición Genética a la Enfermedad , Distribución de Chi-Cuadrado , Estudios de Cohortes , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Masculino , Recurrencia
17.
Phys Chem Chem Phys ; 16(30): 15825-30, 2014 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-24676385

RESUMEN

Recent synthetic work has realized a novel (n-type) small-molecule acceptor, 7,8,15,16-tetra-aza-terrylene (TAT), single-crystals of which can be grown oriented along the c-axis crystallographic direction, and over-coated with pentacene to form a highly ordered donor/acceptor interface for use in organic photovoltaic devices. However, characterization of single TAT crystals reveals highly variable emission spectra and excited state dynamics - properties which strongly influence photovoltaic performance. Through the use of single-crystal widefield imaging, photoluminescence spectroscopy, time correlated single photon counting, and resonant Raman studies, we conclude that this variability is a result of long-lived low-energy trap-emission from packing defects. Interestingly, we also discovered that TAT crystals whose width exceeds ∼200 nm begin acting as waveguides and optical microcavity resonators for their own photoluminescence. Several strategies are proposed for leveraging the size-dependant optical properties of TAT pillars to further enhance device performance using this active layer design.


Asunto(s)
Compuestos Aza/química , Procesos Fotoquímicos , Semiconductores , Análisis Espectral/métodos
18.
Int J Sports Med ; 35(12): 1006-11, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24838267

RESUMEN

The aim of this study was to investigate the effects of acute vibration exercise, at 2 different frequencies, on upper body power output. Muscle activity (EMG) and upper-body peak power was measured in 12 healthy males during ballistic bench press throws at 30% of 1-repetition maximum on a Smith machine. Measures were made prior to, 30 s and 5 min after one of 3 conditions performed for 30 s in a press-up position: side-alternating vibration at 20 Hz, 26 Hz and no vibration. EMG was recorded in the anterior deltoid, triceps brachii and pectoralis major during ballistic bench press throws as well as during application of each condition. While peak power output was higher at 5 min post condition across all conditions, compared to baseline measures (P<0.05), only 20 Hz vibration resulted in a significant increase in peak power output (P<0.05) compared to no vibration. EMG was greater during both vibration conditions, compared to no vibration (P<0.001). However, this difference was not evident during bench press throws when no difference was seen in muscle activity between conditions. These findings suggest that 20 Hz vibration has an ergogenic effect on upper-body power that may be due to peripheral, rather than central, mediated mechanisms.


Asunto(s)
Fuerza Muscular/fisiología , Extremidad Superior/fisiología , Vibración , Ejercicio de Calentamiento/fisiología , Levantamiento de Peso/fisiología , Adulto , Músculo Deltoides/fisiología , Electromiografía , Humanos , Masculino , Músculo Esquelético/fisiología , Músculos Pectorales/fisiología , Adulto Joven
19.
Perfusion ; 29(5): 443-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24534886

RESUMEN

Cerebral embolization during pediatric cardiac surgery may be an underappreciated source of subsequent neurodevelopmental impairment. Transcranial Doppler ultrasound is a neuromonitoring tool that can provide intraoperative surveillance for cerebral embolization. We hypothesized that increased cerebral embolic signals detected during infant cardiac surgery would be associated with worse neurodevelopmental outcomes at follow-up. A study group of 24 children who underwent infant cardiac surgery with transcranial Doppler detection of cerebral embolic signals returned at intermediate follow-up for standardized neurodevelopmental assessment. The children were evaluated using two neurocognitive tests and the parents completed two questionnaires regarding observed behavior. Statistical analysis assessed for correlation between the number of cerebral embolic signals at surgery and the results of the neurodevelopmental assessment. Of the 67 test parameters analyzed, five showed a significant association with the number of embolic signals, yet, all in the contrary direction of the clinical hypothesis, likely representing a Type I error. Thus, in this small cohort of patients, the number of cerebral embolic signals detected during infant cardiac surgery was not shown to be associated with worse neurodevelopmental outcomes at intermediate follow-up. A larger study is probably necessary to ascertain the potential influence of cerebral embolic signals on eventual neurologic outcomes in children. The clinical relevance of cerebral embolic signals during pediatric cardiac surgery remains undetermined and deserves further investigation.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Circulación Cerebrovascular , Desarrollo Infantil , Embolización Terapéutica , Cardiopatías Congénitas , Ultrasonografía Doppler Transcraneal , Cognición , Estudios de Seguimiento , Cardiopatías Congénitas/fisiopatología , Cardiopatías Congénitas/terapia , Humanos , Lactante , Recién Nacido , Masculino
20.
OTJR (Thorofare N J) ; : 15394492241268850, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291971

RESUMEN

Scant evidence exists regarding occupational therapy in carceral settings. Exploring perspectives and experiences to understand current practices is needed. To explore how occupational therapy practitioners (OTPs) navigate evaluation, interventions, and role delineation. Qualitative study using phenomenological and hermeneutic approaches Data gathered through semistructured interviews with seven OTPs with average experience of 16 months, representing six states and four practice settings. Themes were identified by two independent coders who analyzed the data with consensus by third researcher. Four themes emerged: managing contextual challenges, interpersonal professional relationships, evidence-informed services, and client-focused care. Practitioners applied various frames of reference, utilized self-report and observation evaluation methods, and implemented holistic direct and indirect interventions. Understanding and supporting the value of therapeutic relationships, activity/occupational performance analysis, and foci of occupational therapy (OT) domains and processes that emphasize indirect roles can further define and highlight the distinctive nature of OT within carceral settings.


Occupational Therapy Practice in the Carceral SystemResearch indicates occupational therapy practitioners (OTPs) have the skills to support individuals during incarceration and community re-entry. However, practice evidence for occupational therapy (OT) in carceral settings is limited as it is still an emerging practice area. To understand current practices, it is important to identify how OTPs define their role and reason about their clients and the services they provide. Seven OTPs spread across six states in various carceral settings were interviewed. Analysis of responses revealed four themes: managing contextual and interpersonal challenges, interpersonal professional relationships, evidence-informed services, and client-focused care. This study also identified that OTPs apply various theories and frames of reference and use client self-report assessment tools and observation during evaluations to provide a holistic client profile. Ongoing advocacy, staff training, and trauma-informed interventions that can flex as needed are essential. Results suggest the OTPs' reasoning processes are highly complex and align with OT professional reasoning literature.

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