173 research outputs found

    Balancing Surface Energy Terms for Stable Growth of Planar Surfaces

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    We investigate the driving forces that determine the growth mode of heteroepitaxial Ge layers grown from solution on Si substrates with orientations (001), (011) and (111) by transmission electron microscopy (TEM) and atomic force microscopy (AFM). Using liquid phase epitaxy, we can study the influences of strain and surface energy terms independently on effects due to limited surface diffusion. In (001) and (011) orientated layers, {111} faceted islands form (Stranski-Krastanov growth). In contrast, (111) orientated layers grow in a two-dimensional step flow growth mode (Frank-van der Merwe growth). We model these investigations in terms of energy minimisation considering surface energy reduction by formation of faceted islands and elastic strain energy relaxation by island formation. The strain energy relaxation by island formation is calculated by the finite element method. According to our considerations, two-dimensional growth is obtained by selective increase of the free surface energy of the low indices facet planes to a value higher than that of the substrate surface. Formation of faceted islands thus would increase the total surface energy; as a consequence, island formation is suppressed. By choosing the appropriate solvent and temperature in solution growth, we can provide for thermodynamically stable two-dimensional growth

    Vocal Fatigue als Indikator fĂŒr komplexe Stimmstörungen – eine diagnostische und therapeutische Herausforderung

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    Eine alltagseinschrĂ€nkende, pathologische StimmermĂŒdung (Vocal Fatigue) wird v. a. bei BerufssprecherInnen (z. B. LehrerInnen) zunehmend beobachtet und als Indikator fĂŒr komplexe Stimmstörungen betrachtet. Da bislang wenig systematische Studien zu diesem PhĂ€nomen existieren, fehlt bislang eine einheitliche Diagnostik. Anhand der Kasuistik eines Berufssprechers werden Möglichkeiten einer strukturierten Erhebung von Vocal Fatigue vorgestellt und im Hinblick auf ihre laryngoskopischen, instrumentell akustischen („performance fatigue“) und subjektiven Merkmale („perceived fatigue“) diskutiert. Zudem wird eine Abgrenzung zu den Modellen Vocal Effort, Vocal Demand und Vocal Demand Response nach Hunter et al. (2020) vorgenommen. = Vocal fatigue is increasingly observed among professional voice users (e.g., teachers). This pathologic state is associated with restrictions in everyday life and is considered to be an indicator of complex voice disorders. Since there are few systematic studies on the phenomenon, there is currently no uniform definition or diagnostic workup. Based on the case study of a professional speaker, possibilities for a structured vocal fatigue assessment are presented. These are discussed with regard to their laryngoscopic, instrumental acoustic ("performance fatigue") and subjective symptom-related characteristics ("perceived fatigue"). In addition, a differentiation from the vocal effort, vocal demand, and vocal demand response models according to Hunter et al. (2020) is made. Keywords: Muscle tension dysphonia; Vocal Fatigue Index (VFI-D)

    Der deutsche Sydney Swallow Questionnaire

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    Hintergrund Der Sydney Swallow Questionnaire (SSQ) ist ein patientenbasierter Fragebogen zur Erhebung von subjektiven Beschwerden oropharyngealer Schluckstörungen unterschiedlicher Ursachen, mit starker inhalts-, konstrukt-, diskriminativer und prĂ€diktiver ValiditĂ€t. Ziel der Arbeit/Fragestellung Ziel dieser Arbeit war die ÜberprĂŒfung der ReliabilitĂ€t und ValiditĂ€t der deutschen Fassung des Sydney Swallow Questionnaire (SSQ-G). Material und Methode In einer Kreuzvalidierungsstudie fĂŒllten 48 erwachsene deutschsprachige Patienten (12 Frauen/36 MĂ€nner) mit neurogen (n = 16), strukturell (n = 16) und funktionell (n = 16) bedingten Schluckstörungen den deutschen SSQ‑G und MD Anderson Dysphagia Inventory (MDADI) aus. Die ReliabilitĂ€t des SSQ‑G wurde anhand der internen Konsistenz mittels Cronbach‑α berechnet. Die ÜberprĂŒfung der Kriterien- und der KonstruktvaliditĂ€t erfolgte durch eine Kreuzvalidierung mittels Spearman-Korrelationskoeffizient. Ergebnisse Die interne Konsistenz des SSQ‑G war mit Cronbach-α = 0,94 exzellent. Die SSQ-G-Fragen 1 und 17 wiesen mit MDADI-Frage 1 einen moderat signifikanten bzw. hochsignifikanten Korrelationskoeffizienten von −0,43 und −0,45 auf (p < 0,5; p < 0,001). Zwischen Fragen 8, 11 und 12 des SSQ‑G und Fragen 7, 13 und 10 des MDADI lag mit Korrelationen von −0,48 bis −0,55 ein mittlerer bis starker hochsignifikanter Zusammenhang vor (p < 0,001). Somit wurden die ReliabilitĂ€t, die Kriteriums- und KonstruktvaliditĂ€t statistisch bestĂ€tigt. Schlussfolgerung Mit der deutschen Version des SSQ (SSQ-G) können funktionsspezifische Schluckbeschwerden reliabel und valide erfasst werden. In Kombination mit Fragenbögen zur symptomspezifischen LebensqualitĂ€t wie dem MDADI ist somit eine differenziertere klinische Analyse von Schluckbeschwerden möglich

    Lentiviral gene therapy for X-linked chronic granulomatous disease

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    Chronic granulomatous disease (CGD) is a rare inherited disorder of phagocytic cells. We report the initial results of nine severely affected X-linked CGD (X-CGD) patients who received ex vivo autologous CD34+ hematopoietic stem and progenitor cell-based lentiviral gene therapy following myeloablative conditioning in first-in-human studies (trial registry nos. NCT02234934 and NCT01855685). The primary objectives were to assess the safety and evaluate the efficacy and stability of biochemical and functional reconstitution in the progeny of engrafted cells at 12 months. The secondary objectives included the evaluation of augmented immunity against bacterial and fungal infection, as well as assessment of hematopoietic stem cell transduction and engraftment. Two enrolled patients died within 3 months of treatment from pre-existing comorbidities. At 12 months, six of the seven surviving patients demonstrated stable vector copy numbers (0.4–1.8 copies per neutrophil) and the persistence of 16–46% oxidase-positive neutrophils. There was no molecular evidence of either clonal dysregulation or transgene silencing. Surviving patients have had no new CGD-related infections, and six have been able to discontinue CGD-related antibiotic prophylaxis. The primary objective was met in six of the nine patients at 12 months follow-up, suggesting that autologous gene therapy is a promising approach for CGD patients

    Early visual ERPs show stable body-sensitive patterns over a 4-week test period

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    Event-related potential (ERP) studies feature among the most cited papers in the field of body representation, with recent research highlighting the potential of ERPs as neuropsychiatric biomarkers. Despite this, investigation into how reliable early visual ERPs and body-sensitive effects are over time has been overlooked. This study therefore aimed to assess the stability of early body-sensitive effects and visual P1, N1 and VPP responses. Participants were asked to identify pictures of their own bodies, other bodies and houses during an EEG test session that was completed at the same time, once a week, for four consecutive weeks. Results showed that amplitude and latency of early visual components and their associated body-sensitive effects were stable over the 4-week period. Furthermore, correlational analyses revealed that VPP component amplitude might be more reliable than VPP latency and specific electrode sites might be more robust indicators of body-sensitive cortical activity than others. These findings suggest that visual P1, N1 and VPP responses, alongside body-sensitive N1/VPP effects, are robust indications of neuronal activity. We conclude that these components are eligible to be considered as electrophysiological biomarkers relevant to body representation

    Where you look matters for body perception: Preferred gaze location contributes to the body inversion effect

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    The Body Inversion Effect (BIE; reduced visual discrimination performance for inverted compared to upright bodies) suggests that bodies are visually processed configurally; however, the specific importance of head posture information in the BIE has been indicated in reports of BIE reduction for whole bodies with fixed head position and for headless bodies. Through measurement of gaze patterns and investigation of the causal relation of fixation location to visual body discrimination performance, the present study reveals joint contributions of feature and configuration processing to visual body discrimination. Participants predominantly gazed at the (body-centric) upper body for upright bodies and the lower body for inverted bodies in the context of an experimental paradigm directly comparable to that of prior studies of the BIE. Subsequent manipulation of fixation location indicates that these preferential gaze locations causally contributed to the BIE for whole bodies largely due to the informative nature of gazing at or near the head. Also, a BIE was detected for both whole and headless bodies even when fixation location on the body was held constant, indicating a role of configural processing in body discrimination, though inclusion of the head posture information was still highly discriminative in the context of such processing. Interestingly, the impact of configuration (upright and inverted) to the BIE appears greater than that of differential preferred gaze locations

    Integrating Human Health into Environmental Impact Assessment: An Unrealized Opportunity for Environmental Health and Justice

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    The National Environmental Policy Act and related state laws require many public agencies to analyze and disclose potentially significant environmental effects of agency actions, including effects on human health. In this paper we review the purpose and procedures of environmental impact assessment (EIA), existing regulatory requirements for health effects analysis, and potential barriers to and opportunities for improving integration of human health concerns within the EIA process. We use statutes, regulations, guidelines, court opinions, and empirical research on EIA along with recent case examples of integrated health impact assessment (HIA)/EIA at both the state and federal level. We extract lessons and recommendations for integrated HIA/EIA practice from both existing practices as well as case studies. The case studies demonstrate the adequacy, scope, and power of existing statutory requirements for health analysis within EIA. The following support the success of integrated HIA/EIA: a proponent recognizing EIA as an available regulatory strategy for public health; the openness of the agency conducting the EIA; involvement of public health institutions; and complementary objectives among community stakeholders and health practitioners. We recommend greater collaboration among institutions responsible for EIA, public health institutions, and affected stakeholders along with guidance, resources, and training for integrated HIA/EIA practice

    Processing of spatial-frequency altered faces in schizophrenia: Effects of illness phase and duration

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    Low spatial frequency (SF) processing has been shown to be impaired in people with schizophrenia, but it is not clear how this varies with clinical state or illness chronicity. We compared schizophrenia patients (SCZ, n534), first episode psychosis patients (FEP, n522), and healthy controls (CON, n535) on a gender/facial discrimination task. Images were either unaltered (broadband spatial frequency, BSF), or had high or low SF information removed (LSF and HSF conditions, respectively). The task was performed at hospital admission and discharge for patients, and at corresponding time points for controls. Groups were matched on visual acuity. At admission, compared to their BSF performance, each group was significantly worse with low SF stimuli, and most impaired with high SF stimuli. The level of impairment at each SF did not depend on group. At discharge, the SCZ group performed more poorly in the LSF condition than the other groups, and showed the greatest degree of performance decline collapsed over HSF and LSF conditions, although the latter finding was not significant when controlling for visual acuity. Performance did not change significantly over time for any group. HSF processing was strongly related to visual acuity at both time points for all groups. We conclude the following: 1) SF processing abilities in schizophrenia are relatively stable across clinical state; 2) face processing abnormalities in SCZ are not secondary to problems processing specific SFs, but are due to other known difficulties constructing visual representations from degraded information; and 3) the relationship between HSF processing and visual acuity, along with known SCZ- and medication-related acuity reductions, and the elimination of a SCZ-related impairment after controlling for visual acuity in this study, all raise the possibility that some prior findings of impaired perception in SCZ may be secondary to acuity reductions

    Donated chemical probes for open science.

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    Potent, selective and broadly characterized small molecule modulators of protein function (chemical probes) are powerful research reagents. The pharmaceutical industry has generated many high-quality chemical probes and several of these have been made available to academia. However, probe-associated data and control compounds, such as inactive structurally related molecules and their associated data, are generally not accessible. The lack of data and guidance makes it difficult for researchers to decide which chemical tools to choose. Several pharmaceutical companies (AbbVie, Bayer, Boehringer Ingelheim, Janssen, MSD, Pfizer, and Takeda) have therefore entered into a pre-competitive collaboration to make available a large number of innovative high-quality probes, including all probe-associated data, control compounds and recommendations on use (https://openscienceprobes.sgc-frankfurt.de/). Here we describe the chemical tools and target-related knowledge that have been made available, and encourage others to join the project
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