1,202 research outputs found

    Surface-Energy Control and Characterization of Nanoparticle Coatings

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    Accurate and reproducible measurement of the structure and properties of high-value nanoparticles is extremely important for their commercialization. A significant proportion of engineered nanoparticle systems consist of some form of nominally core\u2013shell structure, whether by design or unintentionally. Often, these do not form an ideal core\u2013shell structure, with typical deviations including polydispersity of the core or shell, uneven or incomplete shells, noncentral cores, and others. Such systems may be created with or without intent, and in either case an understanding of the conditions for formation of such particles is desirable. Precise determination of the structure, composition, size, and shell thickness of such particles can prove challenging without the use of a suitable range of characterization techniques. Here, the authors present two such polymer core\u2013shell nanoparticle systems, consisting of polytetrafluoroethylene cores coated with a range of thicknesses of either polymethylmethacrylate or polystyrene. By consideration of surface energy, it is shown that these particles are expected to possess distinctly differing coating structures, with the polystyrene coating being incomplete. A comprehensive characterization of these systems is demonstrated, using a selection of complementary techniques including scanning electron microscopy, scanning transmission electron microscopy, thermogravimetric analysis, dynamic light scattering, differential centrifugal sedimentation, and X-ray photoelectron spectroscopy. By combining the results provided by these techniques, it is possible to achieve superior characterization and understanding of the particle structure than could be obtained by considering results separately

    Sexuality and Affection among Elderly German Men and Women in Long-Term Relationships: Results of a Prospective Population-Based Study

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    This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.The study was funded by the German Federal Ministry for Families, Senior Citizens, Women and Youth (AZ 314-1722-102/16; AZ 301-1720-295/2), the Ministry for Science, Research and Art Baden-Württemberg, and the University of Rostock (FORUN 989020; 889048)

    ifo Konjunkturprognose 2011: Aufschwung setzt sich verlangsamt fort

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    Am 14. Dezember 2010 stellte das ifo Institut im Rahmen seines vorweihnachtlichen Pressegesprächs seine Prognose für die Jahre 2010 und 2011 vor. Die deutsche Wirtschaft hat ihren vor mehr als einem Jahr begonnenen Aufholprozess mit hoher Dynamik fortgesetzt. Nachdem die Impulse dafür zunächst aus dem Ausland gekommen waren, gewann die Binnenwirtschaft in den vergangenen drei Quartalen mehr und mehr an Bedeutung. Besonders wichtig war dafür der Investitionsanreiz, der aus einem historisch niedrigen Zinsniveau resultierte. Die gesamtwirtschaftliche Produktion, getrieben vom kräftig expandierenden industriellen Kern, dürfte im Jahresendquartal 2010 saison- und kalenderbereinigt leicht beschleunigt um 0,8% zugenommen haben. Im Jahresdurchschnitt 2010 expandiert das reale Bruttoinlandsprodukt damit um 3,7%. Im kommenden Jahr bleiben die Konjunkturampeln in Deutschland auf Grün, das Bruttoinlandsprodukt dürfte - bei einem 67%-Unsicherheitsintervall von 1,4 bis 3,4% - um 2,4% steigen. Entscheidend hierfür wird voraussichtlich die Entwicklung der heimischen Nachfrage sein. Bei alledem ist zu erwarten, dass sich die Beschäftigungssituation weiter verbessert. Nachdem die Unternehmen des verarbeitenden Gewerbes in diesem Jahr überwiegend Leiharbeiter eingestellt haben, dürften im kommenden Jahr auch die Stammbelegschaften ausgeweitet werden. Auch werden wohl wieder vermehrt sozialversicherungspflichtige Vollzeitstellen geschaffen. Die Arbeitslosenquote dürfte auf 7,0% sinken. Im Gefolge des Aufschwungs werden die Verbraucherpreise etwas anziehen, mit voraussichtlich 1,7% wird die Inflationsrate aber unter dem Preisziel der EZB bleiben. Das staatliche Budgetdefizit, das im laufenden Jahr in Relation zum nominalen Bruttoinlandsprodukt 3,5% beträgt, wird im nächsten Jahr aufgrund der anhaltend guten Konjunktur, der Konsolidierungsmaßnahmen im Rahmen des Zukunftspakets und der Sparmaßnahmen in der gesetzlichen Krankenversicherung auf 2,3% sinken.

    Shared genetic influences between dimensional ASD and ADHD symptoms during child and adolescent development

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    Abstract Background Shared genetic influences between attention-deficit/hyperactivity disorder (ADHD) symptoms and autism spectrum disorder (ASD) symptoms have been reported. Cross-trait genetic relationships are, however, subject to dynamic changes during development. We investigated the continuity of genetic overlap between ASD and ADHD symptoms in a general population sample during childhood and adolescence. We also studied uni- and cross-dimensional trait-disorder links with respect to genetic ADHD and ASD risk. Methods Social-communication difficulties (N ≤ 5551, Social and Communication Disorders Checklist, SCDC) and combined hyperactive-impulsive/inattentive ADHD symptoms (N ≤ 5678, Strengths and Difficulties Questionnaire, SDQ-ADHD) were repeatedly measured in a UK birth cohort (ALSPAC, age 7 to 17 years). Genome-wide summary statistics on clinical ASD (5305 cases; 5305 pseudo-controls) and ADHD (4163 cases; 12,040 controls/pseudo-controls) were available from the Psychiatric Genomics Consortium. Genetic trait variances and genetic overlap between phenotypes were estimated using genome-wide data. Results In the general population, genetic influences for SCDC and SDQ-ADHD scores were shared throughout development. Genetic correlations across traits reached a similar strength and magnitude (cross-trait r g ≤ 1, p min  = 3 × 10−4) as those between repeated measures of the same trait (within-trait r g ≤ 0.94, p min  = 7 × 10−4). Shared genetic influences between traits, especially during later adolescence, may implicate variants in K-RAS signalling upregulated genes (p-meta = 6.4 × 10−4). Uni-dimensionally, each population-based trait mapped to the expected behavioural continuum: risk-increasing alleles for clinical ADHD were persistently associated with SDQ-ADHD scores throughout development (marginal regression R 2 = 0.084%). An age-specific genetic overlap between clinical ASD and social-communication difficulties during childhood was also shown, as per previous reports. Cross-dimensionally, however, neither SCDC nor SDQ-ADHD scores were linked to genetic risk for disorder. Conclusions In the general population, genetic aetiologies between social-communication difficulties and ADHD symptoms are shared throughout child and adolescent development and may implicate similar biological pathways that co-vary during development. Within both the ASD and the ADHD dimension, population-based traits are also linked to clinical disorder, although much larger clinical discovery samples are required to reliably detect cross-dimensional trait-disorder relationships

    Balancing Selection at the Tomato RCR3 Guardee Gene Family Maintains Variation in Strength of Pathogen Defense

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    Coevolution between hosts and pathogens is thought to occur between interacting molecules of both species. This results in the maintenance of genetic diversity at pathogen antigens (or so-called effectors) and host resistance genes such as the major histocompatibility complex (MHC) in mammals or resistance (R) genes in plants. In plant-pathogen interactions, the current paradigm posits that a specific defense response is activated upon recognition of pathogen effectors via interaction with their corresponding R proteins. According to the''Guard-Hypothesis,'' R proteins (the ``guards'') can sense modification of target molecules in the host (the ``guardees'') by pathogen effectors and subsequently trigger the defense response. Multiple studies have reported high genetic diversity at R genes maintained by balancing selection. In contrast, little is known about the evolutionary mechanisms shaping the guardee, which may be subject to contrasting evolutionary forces. Here we show that the evolution of the guardee RCR3 is characterized by gene duplication, frequent gene conversion, and balancing selection in the wild tomato species Solanum peruvianum. Investigating the functional characteristics of 54 natural variants through in vitro and in planta assays, we detected differences in recognition of the pathogen effector through interaction with the guardee, as well as substantial variation in the strength of the defense response. This variation is maintained by balancing selection at each copy of the RCR3 gene. Our analyses pinpoint three amino acid polymorphisms with key functional consequences for the coevolution between the guardee (RCR3) and its guard (Cf-2). We conclude that, in addition to coevolution at the ``guardee-effector'' interface for pathogen recognition, natural selection acts on the ``guard-guardee'' interface. Guardee evolution may be governed by a counterbalance between improved activation in the presence and prevention of auto-immune responses in the absence of the corresponding pathogen

    De novo mutations in SMCHD1 cause Bosma arhinia microphthalmia syndrome and abrogate nasal development

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    Bosma arhinia microphthalmia syndrome (BAMS) is an extremely rare and striking condition characterized by complete absence of the nose with or without ocular defects. We report here that missense mutations in the epigenetic regulator SMCHD1 mapping to the extended ATPase domain of the encoded protein cause BAMS in all 14 cases studied. All mutations were de novo where parental DNA was available. Biochemical tests and in vivo assays in Xenopus laevis embryos suggest that these mutations may behave as gain-of-function alleles. This finding is in contrast to the loss-of-function mutations in SMCHD1 that have been associated with facioscapulohumeral muscular dystrophy (FSHD) type 2. Our results establish SMCHD1 as a key player in nasal development and provide biochemical insight into its enzymatic function that may be exploited for development of therapeutics for FSHD

    Therapy-refractory Panton Valentine Leukocidin-positive community-acquired methicillin-sensitive Staphylococcus aureus sepsis with progressive metastatic soft tissue infection: a case report

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    We report a case of fulminant multiple organ failure including the Acute Respiratory Distress Syndrome (ARDS), haemodynamic, and renal failure due to community-acquired methicillin-sensitive Panton Valentine Leukocidin (PVL) positive spa-type 284 (ST121) Staphylococcus aureus septic shock. The patient's first clinical symptom was necrotizing pneumonia. Despite organism-sensitive triple antibiotic therapy with linezolid, imipenem and clindamycin from the first day of treatment, progressive abscess formation in multiple skeletal muscles was observed. As a result, repeated surgical interventions became necessary. Due to progressive soft tissue infection, the anti-microbial therapy was changed to a combination of clindamycin and daptomycin. Continued surgical and antimicrobial therapy finally led to a stabilisation of the patients' condition. The clinical course of our patient underlines the existence of a "PVL-syndrome" which is independent of in vitro Staphylococcus aureus susceptibility. The PVL-syndrome should not only be considered in patients with soft tissue or bone infection, but also in patients with pneumonia. Such a condition, which may easily be mistaken for uncomplicated pneumonia, should be treated early, aggressively and over a long period of time in order to avoid relapsing infection
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