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We used a survey to characterize contemporary infection prevention and antibiotic stewardship program practices across 64 healthcare facilities, and we compared these findings to those of a similar 2013 survey. Notable findings include decreased frequency of active surveillance for methicillin-resistant Staphylococcus aureus, frequent active surveillance for carbapenem-resistant Enterobacteriaceae, and increased support for antibiotic stewardship programs.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
Research into new concepts for oxide-electronic devices has been enriched by the emerging field of functional interfaces. A high control of the materials down to the atomic level enables the improvement of existing oxide devices, like magnetic tunnel junctions, but also the formation of new artificial interface phases. Previous work revealed the existence of a metallic electron gas at the interface between the two band-insulators, LaAlO3 and SrTiO3, for a certain atomic arrangement [1,2]. Several studies on single epitaxial connections between LaAlO3 and SrTiO3 have revealed them to be either high-mobility electron conductors or insulating, depending on the atomic stacking sequences. An important point to take into account is the formation of oxygen vacancies for low deposition pressures (<10-5 mbar). For this growth regime the transport properties are fully dominated by the presence of the oxygen vacancies. In this talk we will show a detailed investigation of the controllable electronic properties of coupled interfaces in SrTiO3-LaAlO3-SrTiO3 heterostructures. Recently we reported a critical separation distance of 6 perovskite unit cell layers (~23 Å) for the electronic coupling of closely-spaced complementary interfaces in SrTiO3/LaAlO3 multilayer structures . We showed that a decrease of the interface conductivity and carrier density occurs when the LaO:TiO2 and AlO2:SrO interfaces are brought closer together. Interestingly, the high carrier mobilities characterizing the separate conducting interfaces were found to be maintained in such coupled structures down to sub-nanometer interface spacing. Here, we will explain in more detail the electronic properties of the closely spaced LaO:TiO2 and AlO2:SrO interfaces below the critical separation distance. The carrier density at room temperature for dLAO5 is similar to a single LaO:TiO2 interface and has a value of ~1.5X1014 cm-2, corresponding to ~0.23 electrons per unit cell area on the LaO:TiO2 interface. In this, the contribution by the AlO2:SrO interface to the sheet carrier density is neglected, due to its much lower conductivity. When both interfaces are brought closer to each other the electronic coupling between them is increased and the charge density at room temperature is reduced to 0.15, 0.11 and 0.07 electrons per unit cell area for a spacing of respectively 3, 2 and 1 unit cells. However, for lower temperatures the sheet carrier density decreases and becomes constant for all coupled heterostructures at temperatures below 10 K. This constant low temperature carrier density has a value of 2.0×1013 cm-2 and corresponds to 0.003 electrons per unit cell area. These results show the ability to control the electronic properties in SrTiO3 heterostructures and to vary the carrier density homogeneously over the interface.
Norovirus, a major cause of gastroenteritis in people of all ages worldwide, was first reported in South Korea in 1999. The most common causal agents of pediatric acute gastroenteritis are norovirus and rotavirus. While vaccination has reduced the pediatric rotavirus infection rate, norovirus vaccines have not been developed. Therefore, prediction and prevention of norovirus are very important. Norovirus is divided into genogroups GI–GVII, with GII.4 being the most prevalent. However, in 2012–2013, GII.17 showed a higher incidence than GII.4 and a novel variant, GII.P17-GII.17, appeared. In this study, 204 stool samples collected in 2013–2014 were screened by reverse transcriptase-polymerase chain reaction; 11 GI (5.39%) and 45 GII (22.06%) noroviruses were identified. GI.4, GI.5, GII.4, GII.6 and GII.17 were detected. The whole genomes of the three norovirus GII.17 were sequenced. The whole genome of GII.17 consists of three open reading frames of 5109, 1623 and 780 bp. Compared with 20 GII.17 strains isolated in other countries, we observed numerous changes in the protruding P2 domain of VP1 in the Korean GII.17 viruses. Our study provided genome information that might aid in epidemic prevention, epidemiology studies and vaccine development.
Molecular dynamics simulations of different defective kaolinites under tension were performed to reveal the effects of defect location, type, density and temperature on their mechanical properties. Four types of defective kaolinite with Si vacancies were constructed. Based on the atomic-scale deformation and failure processes of defective kaolinite and its stress–strain curves, the Young's moduli and tensile strengths in three crystal directions were obtained and compared with the existing theoretical values from the literature. The defect location at each layer does not affect the mechanical properties of kaolinite and the cracks initiated at the defective sites. The atom density of each model was calculated in order to investigate the defect-type effect on the mechanical properties of kaolinite. The simulation results also showed that kaolinite exhibits brittle failure behaviour and the mechanical properties degrade significantly with increasing defect density and temperature. The influence of temperature on the mechanical properties of defective kaolinite is discussed in detail.
Childhood maltreatment (CM) plays an important role in the development of major depressive disorder (MDD). The aim of this study was to examine whether CM severity and type are associated with MDD-related brain alterations, and how they interact with sex and age.
Within the ENIGMA-MDD network, severity and subtypes of CM using the Childhood Trauma Questionnaire were assessed and structural magnetic resonance imaging data from patients with MDD and healthy controls were analyzed in a mega-analysis comprising a total of 3872 participants aged between 13 and 89 years. Cortical thickness and surface area were extracted at each site using FreeSurfer.
CM severity was associated with reduced cortical thickness in the banks of the superior temporal sulcus and supramarginal gyrus as well as with reduced surface area of the middle temporal lobe. Participants reporting both childhood neglect and abuse had a lower cortical thickness in the inferior parietal lobe, middle temporal lobe, and precuneus compared to participants not exposed to CM. In males only, regardless of diagnosis, CM severity was associated with higher cortical thickness of the rostral anterior cingulate cortex. Finally, a significant interaction between CM and age in predicting thickness was seen across several prefrontal, temporal, and temporo-parietal regions.
Severity and type of CM may impact cortical thickness and surface area. Importantly, CM may influence age-dependent brain maturation, particularly in regions related to the default mode network, perception, and theory of mind.
Guangxi, a province in southwestern China, has the second highest reported number of HIV/AIDS cases in China. This study aimed to develop an accurate and effective model to describe the tendency of HIV and to predict its incidence in Guangxi. HIV incidence data of Guangxi from 2005 to 2016 were obtained from the database of the Chinese Center for Disease Control and Prevention. Long short-term memory (LSTM) neural network models, autoregressive integrated moving average (ARIMA) models, generalised regression neural network (GRNN) models and exponential smoothing (ES) were used to fit the incidence data. Data from 2015 and 2016 were used to validate the most suitable models. The model performances were evaluated by evaluating metrics, including mean square error (MSE), root mean square error, mean absolute error and mean absolute percentage error. The LSTM model had the lowest MSE when the N value (time step) was 12. The most appropriate ARIMA models for incidence in 2015 and 2016 were ARIMA (1, 1, 2) (0, 1, 2)12 and ARIMA (2, 1, 0) (1, 1, 2)12, respectively. The accuracy of GRNN and ES models in forecasting HIV incidence in Guangxi was relatively poor. Four performance metrics of the LSTM model were all lower than the ARIMA, GRNN and ES models. The LSTM model was more effective than other time-series models and is important for the monitoring and control of local HIV epidemics.
Resonant optical dipole antennas, consisting either of two arms coupled by a small gap or of a single, uncoupled arm only, are fabricated by the application of electron beam lithography and gold evaporation. Using dark-field microscopy, scattering spectra of structures with varied antenna arm length and varied gap size are obtained. The results show not only a spectral redshift for coupled structures compared to single arm structures, but also that the far-field scattering intensity is significantly higher for two arm structures with gap. In addition to the dipole structures, first fabrication results on quadrupole antennas and split-ring antennas are presented, offering novel pathways for an enhancement of the optical response function.
The second order nonlinear optical (NLO) properties of two different ionic selfassembled multilayer (ISAM) films combined with Ag nanoparticles have been investigated. The plasmon resonances in the Ag particles concentrate the incident light, markedly increasing in the NLO efficiencies of the films. We find that the efficiency enhancement is significantly larger in conventional ISAM films compared to films made using a hybrid covalent ISAM technique (HCISAM), even though the intrinsic bulk second order non-linear susceptibility (χ(2)) is much larger for HCISAM films. We attribute this to the interfaces in HCISAM films being much easier to disrupt by external perturbations such as the metal deposition by which the nanoparticles are fabricated. We conclude that because the plasmon decay length is very short, the plasmonic enhancement of NLO effects primarily occurs at and near the film-particle interface. To discern the importance of the interfaces, we surrounded thin ISAM and HCISAM films with NLOinactive buffer layers, which confirmed this hypothesis, particularly in the case of HCISAM films.
Objectives: Craniopharyngioma survivors experience cognitive deficits that negatively impact quality of life. Aerobic fitness is associated with cognitive benefits in typically developing children and physical exercise promotes recovery following brain injury. Accordingly, we investigated cognitive and neural correlates of aerobic fitness in a sample of craniopharyngioma patients. Methods: Patients treated for craniopharyngioma [N=104, 10.0±4.6 years, 48% male] participated in fitness, cognitive and fMRI (n=51) assessments following surgery but before proton radiation therapy. Results: Patients demonstrated impaired aerobic fitness [peak oxygen uptake (PKVO2)=23.9±7.1, 41% impaired (i.e., 1.5 SD<normative mean)], motor proficiency [Bruininks-Oseretsky (BOT2)=38.6±9.0, 28% impaired], and executive functions (e.g., WISC-IV Working Memory Index (WMI)=96.0±15.3, 11% impaired). PKVO2 correlated with better executive functions (e.g., WISC-IV WMI r=.27, p=.02) and academic performance (WJ-III Calculation r=.24, p=.04). BOT2 correlated with better attention (e.g., CPT-II omissions r=.26, p=.04) and executive functions (e.g., WISC-IV WMI r=.32, p=.01). Areas of robust neural activation during an n-back task included superior parietal lobule, dorsolateral prefrontal cortex, and middle and superior frontal gyri (p<.05, corrected). Higher network activation was associated with better working memory task performance and better BOT2 (p<.001). Conclusions: Before adjuvant therapy, children with craniopharyngioma demonstrate significantly reduced aerobic fitness, motor proficiency, and working memory. Better aerobic fitness and motor proficiency are associated with better attention and executive functions, as well as greater activation of a well-established working memory network. These findings may help explain differential risk/resiliency with respect to acute cognitive changes that may portend cognitive late effects. (JINS, 2019, 25, 413–425)
To ascertain opinions regarding etiology and preventability of hospital-onset bacteremia and fungemia (HOB) and perspectives on HOB as a potential outcome measure reflecting quality of infection prevention and hospital care.
Hospital epidemiologists and infection preventionist members of the Society for Healthcare Epidemiology of America (SHEA) Research Network.
A web-based, multiple-choice survey was administered via the SHEA Research Network to 133 hospitals.
A total of 89 surveys were completed (67% response rate). Overall, 60% of respondents defined HOB as a positive blood culture on or after hospital day 3. Central line-associated bloodstream infections and intra-abdominal infections were perceived as the most frequent etiologies. Moreover, 61% thought that most HOB events are preventable, and 54% viewed HOB as a measure reflecting a hospital’s quality of care. Also, 29% of respondents’ hospitals already collect HOB data for internal purposes. Given a choice to publicly report central-line–associated bloodstream infections (CLABSIs) and/or HOB, 57% favored reporting either HOB alone (22%) or in addition to CLABSI (35%) and 34% favored CLABSI alone.
Among the majority of SHEA Research Network respondents, HOB is perceived as preventable, reflective of quality of care, and potentially acceptable as a publicly reported quality metric. Further studies on HOB are needed, including validation as a quality measure, assessment of risk adjustment, and formation of evidence-based bundles and toolkits to facilitate measurement and improvement of HOB rates.
Barley is an important crop worldwide with production largely used for animal feed and alcoholic beverages. Diseases are a major limiting factor to its production. These have, up until recently, been controlled by agrochemicals. However, legislation on the use of agrochemicals, especially within the European Union, is being tightened and there is growing interest in integrated pest management. This means that there is an increasing focus on controlling diseases using biological control. Living microorganisms that are applied as biological control agents (BCAs) to either soil, seed or leaves can have difficulty in persisting. Therefore, the focus of this review is on endophytes, which are microorganisms that live inside the plant without causing symptoms of disease and have the potential of staying protected as well as being beneficial to the plant and effective against multiple diseases. In this review, we discuss the different approaches for finding and testing beneficial endophytes and for determining the endophyte host range. Furthermore, we undertook a literature search to summarise previous studies that have investigated the use of endophytes as well as BCAs against barley diseases.
There are increasing efforts aiming to utilise endophytes as biological control agents (BCAs) to improve crop production. However, reliability remains a major practical constraint for the development of novel BCAs. Many organisms are adapted to their specific habitat; it is optimistic to expect that a new organism added can find a niche or even out-compete those adapted and already present. Our approach for isolating novel BCAs for specific plant diseases is therefore to look in healthy plants in a habitat where disease is a problem, since we predict that it is more likely to find competitive strains among those present and adapted. In vitro inhibitory activities often do not correlate with in planta efficacy, especially since endophytes rely on intimate plant contact. They can, however, be useful to indicate modes of action. We therefore screen for in planta biological activity as early as possible in the process in order to minimise the risk of discarding valuable strains. Finally, some fungi are endophytic in one situation and pathogenic in another (the mutualism–parasitism continuum). This depends on their biology, environmental conditions, the formulation of inoculum, the health, developmental stage and cultivar of the host plant, and the structure of the plant microbiome.
Objectives: Apathy is a debilitating symptom of Huntington’s disease (HD) and manifests before motor diagnosis, making it an excellent therapeutic target in the preclinical phase of Huntington’s disease (prHD). HD is a neurological genetic disorder characterized by cognitive and motor impairment, and psychiatric abnormalities. Apathy is not well characterized within the prHD. In previous literature, damage to the caudate and putamen has been correlated with increased apathy in other neurodegenerative and movement disorders. The objective of this study was to determine whether apathy severity in individuals with prHD is related to striatum volumes and cognitive control. We hypothesized that, within prHD individuals, striatum volumes and cognitive control scores would be related to apathy. Methods: We constructed linear mixed models to analyze striatum volumes and cognitive control, a composite measure that includes tasks assessing with apathy scores from 797 prHD participants. The outcome variable for each model was apathy, and the independent variables for the four separate models were caudate volume, putamen volume, cognitive control score, and motor symptom score. We also included depression as a covariate to ensure that our results were not solely related to mood. Results: Caudate and putamen volumes, as well as measures of cognitive control, were significantly related to apathy scores even after controlling for depression. Conclusions: The behavioral apathy expressed by these individuals was related to regions of the brain commonly associated with isolated apathy, and not a direct result of mood symptoms. (JINS, 2019, 25, 462–469)
Nanocarbon materials, such as carbon nanotubes, graphene, and their derivatives, are regarded as promising reinforcing agents in metal matrix composites (MMCs) because of their excellent intrinsic mechanical properties. Considering the various types of nanocarbons with different defect states and intrinsic properties, there is a potential for tailoring the mechanical behavior of nanocarbon-reinforced MMCs. This article reviews recent developments in both the processing and the structure–property correlations of these composites. Particular emphasis is given to the structure and properties of the nanocarbon–metal interfaces, as the external mechanical load is transferred between the nanocarbon and the metal matrix across their interfaces. Moreover, in addition to the intuitive load-bearing effect of the nanocarbon reinforcements, a copious interplay between nanocarbons and dislocations in the metal matrix has been found, which alters the deformation behavior that leads to additional strengthening. For structural applications, scalable fabrication routes for the nanocarbon-metal composites need to be developed, and studies on the mechanical behavior under real service conditions are needed.