471 research outputs found

    Single-dot Spectroscopy of GaAs Quantum Dots Fabricated by Filling of Self-assembled Nanoholes

    Get PDF
    We study the optical emission of single GaAs quantum dots (QDs). The QDs are fabricated by filling of nanoholes in AlGaAs and AlAs which are generated in a self-assembled fashion by local droplet etching with Al droplets. Using suitable process parameters, we create either uniform QDs in partially filled deep holes or QDs with very broad size distribution in completely filled shallow holes. Micro photoluminescence measurements of single QDs of both types establish sharp excitonic peaks. We measure a fine-structure splitting in the range of 22–40μeV and no dependence on QD size. Furthermore, we find a decrease in exciton–biexciton splitting with increasing QD size

    Histological validation of a type 1 diabetes clinical diagnostic model for classification of diabetes

    Get PDF
    This is the final version. Available on open access from Wiley via the DOI in this recordAims: Misclassification of diabetes is common due to an overlap in the clinical features of type 1 and type 2 diabetes. Combined diagnostic models incorporating clinical and biomarker information have recently been developed that can aid classification, but they have not been validated using pancreatic pathology. We evaluated a clinical diagnostic model against histologically defined type 1 diabetes. Methods: We classified cases from the Network for Pancreatic Organ donors with Diabetes (nPOD) biobank as type 1 (n = 111) or non-type 1 (n = 42) diabetes using histopathology. Type 1 diabetes was defined by lobular loss of insulin-containing islets along with multiple insulin-deficient islets. We assessed the discriminative performance of previously described type 1 diabetes diagnostic models, based on clinical features (age at diagnosis, BMI) and biomarker data [autoantibodies, type 1 diabetes genetic risk score (T1D-GRS)], and singular features for identifying type 1 diabetes by the area under the curve of the receiver operator characteristic (AUC-ROC). Results: Diagnostic models validated well against histologically defined type 1 diabetes. The model combining clinical features, islet autoantibodies and T1D-GRS was strongly discriminative of type 1 diabetes, and performed better than clinical features alone (AUC-ROC 0.97 vs. 0.95; P = 0.03). Histological classification of type 1 diabetes was concordant with serum C-peptide [median < 17 pmol/l (limit of detection) vs. 1037 pmol/l in non-type 1 diabetes; P < 0.0001]. Conclusions: Our study provides robust histological evidence that a clinical diagnostic model, combining clinical features and biomarkers, could improve diabetes classification. Our study also provides reassurance that a C-peptide-based definition of type 1 diabetes is an appropriate surrogate outcome that can be used in large clinical studies where histological definition is impossible. Parts of this study were presented in abstract form at the Network for Pancreatic Organ Donors Conference, Florida, USA, 19–22 February 2019 and Diabetes UK Professional Conference, Liverpool, UK, 6–8 March 2019.Diabetes UKNational Institutes of Health (NIH)National Institute for Health Research (NIHR)JDRFHelmsley Charitable Trus

    Superposition operators between weighted Banach spaces of analytic functions of controlled growth

    Full text link
    The final publication is available at Springer via: http://dx.doi.org/10.1007/s00605-012-0441-6[EN] We characterize the entire functions which transform a weighted Banach space of holomorphic functions on the disc of type H∞ into another such space by superposition. We also show that all the superposition operators induced by such entire functions map bounded sets into bounded sets and are continuous. Superposition operators that map bounded sets into relatively compact sets are also considered. © 2012 Springer-Verlag Wien.The research of Bonet was partially supported by MICINN and FEDER Project MTM2010-15200, by GV project Prometeo/2008/101, and by ACOMP/2012/090. The research of Vukotic was partially supported by MICINN grant MTM2009-14694-C02-01, Spain and by the European ESF Network HCAA ("Harmonic and Complex Analysis and Its Applications").Bonet Solves, JA.; Vukotić, D. (2013). Superposition operators between weighted Banach spaces of analytic functions of controlled growth. Monatshefte für Mathematik. 170(3-4):311-323. https://doi.org/10.1007/s00605-012-0441-6S3113231703-4Álvarez, V., Márquez, M.A., Vukotić, D.: Superposition operators between the Bloch space and Bergman spaces. Ark. Mat. 42, 205–216 (2004)Appell, J., Zabrejko, P.P.: Nonlinear Superposition Operators, Cambridge Tracts in Mathematics 95. Cambridge University Press, London (1990)Appell, J., Zabrejko, P.P.: Remarks on the superposition operator problem in various function spaces. Complex Var. Elliptic Equ. 55(8–10), 727–737 (2010)Bierstedt, K.D., Bonet, J., Galbis, A.: Weighted spaces of holomorphic functions on bounded domains. Michigan Math. J. 40, 271–297 (1993)Bierstedt, K.D., Bonet, J., Taskinen, J.: Associated weights and spaces of holomorphic functions. Studia Math. 127, 137–168 (1998)Bonet, J., Domański, P., Lindström, M.: Essential norm and weak compactness of composition operators on weighted Banach spaces of analytic functions. Can. Math. Bull. 42(2), 139–148 (1999)Bonet, J., Domański, P., Lindström, M., Taskinen, J.: Composition operators between weighted Banach spaces of analytic functions. J. Aust. Math. Soc. (Ser. A) 64, 101–118 (1998)Boyd, C., Rueda, P.: Holomorphic superposition operators between Banach function spaces. Preprint (2011)Boyd, C., Rueda, P.: Superposition operators between weighted spaces of analytic functions. Preprint (2011)Buckley, S.M., Fernández, J.L., Vukotić, D.: Superposition operators on Dirichlet type spaces. In: Papers on Analysis: A Volume dedicaed to Olli Martio on the occasion of his 60th birthday. Rep. Univ. Jyväskyla Dept. Math. Stat, vol. 83, pp. 41–61. Univ. Jyväskyla, Jyväskyla (2001)Buckley, S.M., Vukotić, D.: Univalent interpolation in Besov spaces and superposition into Bergman spaces. Potential Anal. 29(1), 1–16 (2008)Cámera, G.A.: Nonlinear superposition on spaces of analytic functions. In: Harmonic Analysis and Operator Theory (Carácas, 1994), Contemp. Math, vol. 189, pp. 103–116. Am. Math. Soc, Providence (1995)Cámera, G.A., Giménez, J.: The nonlinear superposition operators acting on Bergman spaces. Compositio Math. 93, 23–35 (1994)Castillo, R.E., Ramos Fernández, J.C., Salazar, M.: Bounded superposition operators between Bloch-Orlicz and α\alpha -Bloch spaces. Appl. Math. Comp. 218, 3441–3450 (2011)Dineen, S.: Complex Analysis in Locally Convex Spaces, vol. 57. North-Holland Math. Studies, Amsterdam (1981)Girela, D., Márquez, M.A.: Superposition operators between QpQ_p spaces and Hardy spaces. J. Math. Anal. Appl. 364, 463–472 (2010)Grosse-Erdmann, K.-G.: A weak criterion for vector-valued holomorphic functions. Math. Proc. Camb. Publ. Soc. 136, 399–41 (2004)Harutyunyan, A., Lusky, W.: On the boundedness of the differentiation operator between weighted spaces of holomorphic functions. Studia Math. 184, 233–247 (2008)Langenbruch, M.: Continuation of Gevrey regularity for solutions of partial differential operators. In: Functional Analysis (Trier, 1994), pp. 249–280. de Gruyter, Berlin (1996)Levin, B.Ya.: Lectures on Entire Functions. Translations of Mathematical Monographs, vol. 150, Amer. Math. Soc., Providence (1996).Lusky, W.: On weighted spaces of harmonic and holomorphic functions. J. Lond. Math. Soc. 51, 309–320 (1995)Lusky, W.: On the isomorphism classes of weighted spaces of harmonic and holomorphic functions. Studia Math. 175, 19–45 (2006)Pommerenke, Ch.: Boundary Behaviour of Conformal Maps. Springer, Berlin (1992)Ramos Fernández, J.C.: Bounded superposition operators between weighted Banach spaces of analytic functions. Preprint, Available from http://arxiv.org/abs/1203.5857Shields, A.L., Williams, D.L.: Bounded projections, duality and multipliers in spaces of analytic functions. Trans. Am. Math. Soc. 162, 287–302 (1971)Vukotić, D.: Integrability, growth of conformal maps, and superposition operators, Technical Report 10. Aristotle University of Thessaloniki, Department of Mathematics (2004)Xiong, C.: Superposition operators between QpQ_p spaces and Bloch-type spaces. Complex Var. Theory Appl. 50, 935–938 (2005)Xu, W.: Superposition operators on Bloch-type spaces. Comput. Methods Funct. Theory 7, 501–507 (2007)Zhu, K.: Operator Theory in Function Spaces, 2nd edn. Am. Math. Soc., Providence (2007

    Monoubiquitination of syntaxin 3 leads to retrieval from the basolateral plasma membrane and facilitates cargo recruitment to exosomes

    Get PDF
    Syntaxin 3 (Stx3), a SNARE protein located and functioning at the apical plasma membrane of epithelial cells, is required for epithelial polarity. A fraction of Stx3 is localized to late endosomes/lysosomes, although how it traffics there and its function in these organelles is unknown. Here we report that Stx3 undergoes monoubiquitination in a conserved polybasic domain. Stx3 present at the basolateral—but not the apical—plasma membrane is rapidly endocytosed, targeted to endosomes, internalized into intraluminal vesicles (ILVs), and excreted in exosomes. A nonubiquitinatable mutant of Stx3 (Stx3-5R) fails to enter this pathway and leads to the inability of the apical exosomal cargo protein GPRC5B to enter the ILV/exosomal pathway. This suggests that ubiquitination of Stx3 leads to removal from the basolateral membrane to achieve apical polarity, that Stx3 plays a role in the recruitment of cargo to exosomes, and that the Stx3-5R mutant acts as a dominant-negative inhibitor. Human cytomegalovirus (HCMV) acquires its membrane in an intracellular compartment and we show that Stx3-5R strongly reduces the number of excreted infectious viral particles. Altogether these results suggest that Stx3 functions in the transport of specific proteins to apical exosomes and that HCMV exploits this pathway for virion excretion

    Spatio-temporal Models of Lymphangiogenesis in Wound Healing

    Full text link
    Several studies suggest that one possible cause of impaired wound healing is failed or insufficient lymphangiogenesis, that is the formation of new lymphatic capillaries. Although many mathematical models have been developed to describe the formation of blood capillaries (angiogenesis), very few have been proposed for the regeneration of the lymphatic network. Lymphangiogenesis is a markedly different process from angiogenesis, occurring at different times and in response to different chemical stimuli. Two main hypotheses have been proposed: 1) lymphatic capillaries sprout from existing interrupted ones at the edge of the wound in analogy to the blood angiogenesis case; 2) lymphatic endothelial cells first pool in the wound region following the lymph flow and then, once sufficiently populated, start to form a network. Here we present two PDE models describing lymphangiogenesis according to these two different hypotheses. Further, we include the effect of advection due to interstitial flow and lymph flow coming from open capillaries. The variables represent different cell densities and growth factor concentrations, and where possible the parameters are estimated from biological data. The models are then solved numerically and the results are compared with the available biological literature.Comment: 29 pages, 9 Figures, 6 Tables (39 figure files in total

    Outcomes of Operatively Treated Acute Knee Dislocations

    Get PDF
    Knee dislocation is a complex and rare injury often presenting in the context of high velocity trauma. The aim of this study is to establish the subjective outcomes of surgically treated knee dislocations. A total of 20 knees dislocations treated by open repair were reviewed. Their progress and outcomes were assessed by using a modified Lysholm score questionnaire. Data was obtained on patient demographics, details of injury, investigation, treatment, rehabilitation, 24 months objective outcome and subjective outcomes. Six patients had a vascular deficit and six had neurological deficits. The median range of motion was 0°-100°. Patients with an initially lower pre-injury level of function were able to return an activity level comparable to their pre-injury status. 22% of competitive athletes retuned to competitive sports. 38% of patients undertaking heavy activity returned to comparable pre-injury level of activity and 67% of patients undertaking moderate level of activity before injury returned to a comparable level after repair. 68% regularly had problems running, 70% problem squatting, 40% swelling and 42% problem with stairs. Most patients however did not have locking of the knee or problems with knees giving way. Patients pain scores decreased over time to an acceptable level. Despite the severity of the injury, majority of patients achieved a satisfactory outcome, although none of the patients reached the same level of function as before the injury. 80% of the patients were satisfied with their outcome. All dissatisfied patients suffered postoperative complications

    High density of peritumoral lymphatic vessels is a potential prognostic marker of endometrial carcinoma: a clinical immunohistochemical method study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The lymphatic system is a major route for cancer cell dissemination and also a potential target for antitumor therapy. To investigate whether increased lymphatic vessel density (LVD) is a prognostic factor for nodal metastasis and survival, we studied peritumoral LVD (P-LVD) and intratumoral LVD (I-LVD) in samples from 102 patients with endometrial carcinoma;</p> <p>Methods</p> <p>Endometrial carcinoma tissues were analyzed for lymphatic vessels by immunohistochemical staining with an antibody against LYVE-1. Univariate analysis was performed with Kaplan-Meier life-table curves to estimate survival, and was compared using the log rank test. Prognostic models used multivariate Cox regression analysis for multivariate analyses of survival;</p> <p>Results</p> <p>Our study showed that P-LVD, but not I-LVD, was significantly correlated with lymph vascular space invasion (LVSI), lymph node metastasis, tumor stage, and CD44 expression in endometrial carcinoma. Moreover, P-LVD was an independent prognostic factor for progression-free survival and overall survival of endometrial carcinoma;</p> <p>Conclusions</p> <p>P-LVD may serve as a prognostic factor for endometrial carcinoma. The peritumoral lymphatics might play an important role in lymphatic vessel metastasis.</p

    Satisfaction with care after total hip or knee replacement predicts self-perceived health status after surgery

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Inpatient satisfaction with care is a standard indicator of the quality of care delivered during hospitalization. Total hip and knee replacement (THR/TKR) for osteoarthritis (OA) are among the most successful orthopaedic interventions having a positive impact on health-related quality of life (HRQoL). The aim was to evaluate the effect of satisfaction shortly after hospital discharge on 1-month, 6-month and 1-year Medical Outcomes Study 36-item Short Form (SF-36) scores for OA patients after THR and TKR, controlling for patient characteristics, clinical presentation and preoperative SF-36 scores.</p> <p>Methods</p> <p>A multicenter prospective cohort study recruited 231 patients with OA scheduled to receive THR or TKR. Satisfaction was assessed by the Patients Judgment of Hospital Quality (PJHQ) questionnaire and HRQoL by the SF-36 questionnaire. Linear models for repeated measures assessed the relation between satisfaction (scores were dichotomized) and postoperative SF-36 scores.</p> <p>Results</p> <p>Of 231 participants, 189 were followed up 12 months after discharge (mean age 69 SD = 8; 42.6% male). The mean length of hospital stay was 13.5 (SD = 4) days. After adjustment for preoperative SF-36 scores, sociodemographic and clinical patient characteristics, satisfied patients (PJHQ score > 70) had higher SF-36 scores 1 year after surgery than did less-satisfied patients. Admission, medical care, and nursing and daily care scores mainly predicted bodily pain, mental health, social functioning, vitality and general health scores of the SF-36.</p> <p>Conclusion</p> <p>Besides being a quality-of-care indicator, immediate postoperative patient satisfaction with care may bring a new insight into clinical practice, as a predictor of self-perceived health status after surgery.</p

    Adolescent Loneliness and Social Skills:Agreement and Discrepancies Between Self-, Meta-, and Peer-Evaluations

    Get PDF
    Contains fulltext : 160961.pdf (publisher's version ) (Open Access)Lonely adolescents report that they have poor social skills, but it is unknown whether this is due to an accurate perception of a social skills deficit, or a biased negative perception. This is an important distinction, as actual social skills deficits require different treatments than biased negative perceptions. In this study, we compared self-reported social skills evaluations with peer-reported social skills and meta-evaluations of social skills (i.e., adolescents' perceptions of how they believe their classmates evaluate them). Based on the social skills view, we expected negative relations between loneliness and these three forms of social skills evaluations. Based on the bias view, we expected lonely adolescents to have more negative self- and meta-evaluations compared to peer-evaluations of social skills. Participants were 1342 adolescents (48.64 % male, M age = 13.95, SD = .54). All classmates rated each other in a round-robin design to obtain peer-evaluations. Self- and meta-evaluations were obtained using self-reports. Data were analyzed using polynomial regression analyses and response surface modeling. The results indicated that, when self-, peer- and meta-evaluations were similar, a greater sense of loneliness was related to poorer social skills. Loneliness was also related to larger discrepancies between self- and peer-evaluations of loneliness, but not related to the direction of these discrepancies. Thus, for some lonely adolescents, loneliness may be related to an actual social skills deficit, whereas for others a biased negative perception of one's own social skills or a mismatch with the environment may be related to their loneliness. This implies that different mechanisms may underlie loneliness, which has implications for interventions.11 p

    Using focused ethnography in paediatric settings to explore professionals' and parents' attitudes towards expertise in managing chronic kidney disease stage 3-5

    Get PDF
    © 2014 Nightingale et al.; licensee BioMed Central Ltd. Background: Interactions between parents and healthcare professionals are essential when parents of children with chronic conditions are learning to share expertise about clinical care, but limited evidence exists on how they actually interact. This paper discusses the use of focused ethnography in paediatric settings as an effective means of exploring attitudes towards expertise. Methods: The paper draws on repeated observations, interviews and field-notes involving the parents of six children with chronic kidney disease, and 28 healthcare professionals at two, tertiary, children's hospital-based units. Data were analysed using the Framework approach and the concepts of expertise and self-management. Results: Our study highlighted rewards and challenges associated with focused ethnography in this context. Rewards included the ability to gain a richer understanding of the complex phenomena of mutual acknowledgement of expertise that occurs during parent/ healthcare professional interactions. Challenges related to gaining informed consent and ensuring potential participants had an adequate understanding of the purpose of the study. Two dimensions of parental expertise around their child (personal and clinical) were evident in our data. Parents' and professionals' expertise about the child and their condition was acknowledged and exchanged as parents learnt to share clinical-care with the multi-disciplinary team. Healthcare professionals acknowledged parents' need to understand aspects of each of the eight disciplinary knowledge bases relating to their child' s management and recognised parents' expert knowledge of their child, found ways to mobilise this knowledge, and wove parents' expertise into the management plan. Parents spoke of the degree to which their own expert knowledge of their child complemented healthcare professionals' clinical knowledge. However, ambivalence around expertise was evident as both parents and healthcare professionals questioned what the expertise was, and who the expert was. Our discussion focuses on the ways healthcare professionals and parents share expertise around the child's condition as parents take on responsibility for home-based clinical care. Conclusions: Our findings point to focused ethnography being an effective way of capturing new insights into parent and professional interactions in a paediatric setting and mutual acknowledgement of expertise; these insights may help redress the reported limitations of previous, retrospective studies
    corecore