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Management and Organization Review (MOR) is announcing a renewed initiative that seeks to encourage and publish research reporting engaged indigenous scholarship in China. MOR invites empirical as well as conceptual studies of indigenous phenomena related to management and organizations. MOR welcomes exploratory studies of new, emerging, and/or poorly understood indigenous research questions that employ abductive reasoning and creative hunches, as opposed to testing hypotheses deduced from non-indigenous Western theories. Data on indigenous phenomena can come from any source, including qualitative and quantitative data from case studies, field surveys, experiments, and ethnographies.
Objectives: The aim of this study was to identify whether the three main primary progressive aphasia (PPA) variants would show differential profiles on measures of visuospatial cognition. We hypothesized that the logopenic variant would have the most difficulty across tasks requiring visuospatial and visual memory abilities. Methods: PPA patients (n=156), diagnosed using current criteria, and controls were tested on a battery of tests tapping different aspects of visuospatial cognition. We compared the groups on an overall visuospatial factor; construction, immediate recall, delayed recall, and executive functioning composites; and on individual tests. Cross-sectional and longitudinal comparisons were made, adjusted for disease severity, age, and education. Results: The logopenic variant had significantly lower scores on the visuospatial factor and the most impaired scores on all composites. The nonfluent variant had significant difficulty on all visuospatial composites except the delayed recall, which differentiated them from the logopenic variant. In contrast, the semantic variants performed poorly only on delayed recall of visual information. The logopenic and nonfluent variants showed decline in figure copying performance over time, whereas in the semantic variant, this skill was remarkably preserved. Conclusions: This extensive examination of performance on visuospatial tasks in the PPA variants solidifies some previous findings, for example, delayed recall of visual stimuli adds value in differential diagnosis between logopenic variant PPA and nonfluent variant PPA variants, and illuminates the possibility of common mechanisms that underlie both linguistic and non-linguistic deficits in the variants. Furthermore, this is the first study that has investigated visuospatial functioning over time in the PPA variants. (JINS, 2018, 24, 259–268)
Since the austral summer of 1994-95 the Alfred Wegener Institute has carried out airborne radio-echo sounding (RES) measurements in Antarctica with its newly designed RES system. Since 1995-96 an ongoing pre-site survey for an ice-coring drill site in Dronning Maud Land has been carried out as part of the European Project for Ice Goring in Antarctica. The survey covers an area of 948 000 km2, with >49 500 km of airborne RES obtained from >200 hours of flight operation flown during the period 1994-97. In this paper, first results of the airborne RES survey are graphically summarized as newly derived maps of the ice thickness and subglacial topography, as well as a three-dimensional view of surface and subglacial bed and outcrop topography, revealing a total ice volume of 1.48 x 106 km3.
Since 1994 the Alfred Wegener Institute (AWI) has operated an airborne radio-echo sounding system for remote-sensing studies of the polar ice caps in Antarctica and in Greenland. It is used to map ice thicknesses and internal layernigs of glaciers, ice sheets and ice shelves, and is capable of penetrating ice thicknesses of up to 4 km. The system was designed and built by AWI in cooperation with Aerodata Flugmeßtechnik GmbH, Technische Umversitat Hamburg-Harburg and the Deutsches Zentrum fur Luft- und Raumfahrt e.V. The system uses state-of-the-art techniques, and results in high vertical (5 m) as well as along-track (3.25 m) resolution. The radar signal is a 150 MHz burst with a duration of 60 or 600 ns. The peak power is 1.6 kW, and the system sensitivity is 190 dB. The short backfire principle has been adopted and optimized for antennae used on Polar2, a Dormer 228-100 aircraft, resulting in an antenna gain of 14 dB each. Digital data recording allows further processing. The quality of the recorded data can be monitored on screen and as online analogue plots during the flight.
Return visits to the emergency department (RTED) for the same clinical complaint occur in 2.7% to 8.1% of children presenting to pediatric emergency departments (PEDs). Most studies examining RTEDs have focused solely on PEDs and do not capture children returning to other local emergency departments (EDs). Our objective was to measure the frequency and characterize the directional pattern of RTED to any of 18 EDs serving a large geographic area for children initially evaluated at a PED.
We conducted a retrospective cohort study of all visits to a referral centre PED between August 2012 and August 2013. We compared demographic variables between children with and without an RTED, measures of flow and disposition outcomes between the initial (index) visit and RTED, and between RTED to the original PED versus to other EDs in the community.
Among all PED visits, 7.6% had an RTED within 7 days, of which 13% were to a facility other than the original PED. Children with an RTED had higher acuity and longer length of stay on their index visit. They were also more likely to be admitted on a subsequent visit than the overall PED population. RTED to the original PED had a longer waiting time (WT), length of stay, and more frequently resulted in hospitalization than RTED to a general ED.
A significant proportion of RTED occur at a site other than where the original ED visit occurred. Examining RTED to and from only PEDs underestimates its burden on emergency health services.
An MP tandem Van de Graaff accelerator at the University of Rochester has been employed since May 1977 to detect 14C in various terrestrial samples. The carbon sample sizes required are 1mg or less. Dating accuracies based on reproducibility now approach (± 80 years). Measurements have been made on 1850 wood, Australian sucrose, a carbon sample from Mt Shasta, a baby woolly mammoth, and an Egyptian bull mummy wrapping.
The Cosmic Background Explorer, launched November 18, 1989, has nearly completed its first full mapping of the sky with all three of its instruments: a Far Infrared Absolute Spectrophotometer (FIRAS) covering 0.1 to 10 mm, a set of Differential Microwave Radiometers (DMR) operating at 3.3, 5.7, and 9.6 mm, and a Diffuse Infrared Background Experiment (DIRBE) spanning 1 to 300 µm in ten bands. A preliminary map of the sky derived from DIRBE data is presented. Initial cosmological implications include: a limit on the Comptonization y parameter of 10−3, on the chemical potential μ parameter of 10−2, a strong limit on the existence of a hot smooth intergalactic medium, and a confirmation that the dipole anisotropy has the spectrum expected from a Doppler shift of a blackbody. There are no significant anisotropies in the microwave sky detected, other than from our own galaxy and a cosθ dipole anisotropy whose amplitude and direction agree with previous data. At shorter wavelengths, the sky spectrum and anisotropies are dominated by emission from ‘local’ sources of emission within our Galaxy and Solar System. Preliminary comparison of IRAS and DIRBE sky brightnesses toward the ecliptic poles shows the IRAS values to be significantly higher than found by DIRBE at 100 μm. We suggest the presence of gain and zero-point errors in the IRAS total brightness data. The spacecraft, instrument designs, and data reduction methods are described.
A monolithic fuel design based on U–Mo alloy has been selected as the fuel type for conversion of United States’ high-performance research reactors (USHPRRs) from highly enriched uranium (HEU) to low-enriched uranium (LEU). In this fuel design, a thin layer of zirconium is used to eliminate the direct interaction between the U–Mo fuel meat and the aluminum-alloy cladding during irradiation. The co-rolling process used to bond the Zr barrier layer to the U–Mo foil during fabrication alters the microstructure of both the U–10Mo fuel meat and the U–Mo/Zr interface. This work studied the effects of post-rolling annealing treatment on the microstructure of the co-rolled U–Mo fuel meat and the U–Mo/Zr interaction layer. The U–Mo/Zr interaction-layer thickness increased with the annealing temperature with an Arrhenius constant for growth of 184kJ/mole, consistent with a previous diffusion-couple study. The phases in the U–Mo/Zr interaction layer produced by co-rolling, however, differ from those reported in the previous diffusion-couple study.
It is well known that web-based interventions can be effective treatments for depression. However, dropout rates in web-based interventions are typically high, especially in self-guided web-based interventions. Rigorous empirical evidence regarding factors influencing dropout in self-guided web-based interventions is lacking due to small study sample sizes. In this paper we examined predictors of dropout in an individual patient data meta-analysis to gain a better understanding of who may benefit from these interventions.
A comprehensive literature search for all randomized controlled trials (RCTs) of psychotherapy for adults with depression from 2006 to January 2013 was conducted. Next, we approached authors to collect the primary data of the selected studies. Predictors of dropout, such as socio-demographic, clinical, and intervention characteristics were examined.
Data from 2705 participants across ten RCTs of self-guided web-based interventions for depression were analysed. The multivariate analysis indicated that male gender [relative risk (RR) 1.08], lower educational level (primary education, RR 1.26) and co-morbid anxiety symptoms (RR 1.18) significantly increased the risk of dropping out, while for every additional 4 years of age, the risk of dropping out significantly decreased (RR 0.94).
Dropout can be predicted by several variables and is not randomly distributed. This knowledge may inform tailoring of online self-help interventions to prevent dropout in identified groups at risk.
Airborne electromagnetics (AEM) is an effective technique for geophysical investigations of the shallow subsurface and has successfully been applied in various geological settings to analyse the depositional architecture of sedimentary systems for groundwater and environmental purposes. However, interpretation of AEM data is often restricted to 1D inversion results imaged on resistivity maps and vertical resistivity sections. The integration of geophysical data based on AEM surveys with geological data is often missing and this deficiency can lead to uncertainties in the interpretation process. The aim of this study is to provide an improved methodology for the interpretation of AEM data and the construction of more realistic 3D geological subsurface models. This is achieved by the development of an integrated workflow and 3D modelling approaches based on combining different geophysical and geological data sets (frequency-domain helicopter-borne electromagnetic data (HFEM), time-domain helicopter-borne electromagnetic data (HTEM), three 2D reflection seismic sections and 488 borehole logs). We used 1D inversion results gained from both HFEM and HTEM surveys and applied a 3D resistivity gridding procedure based on geostatistical analyses and interpolation techniques to create continuous 3D resistivity grids. Subsequently, geological interpretations have been performed by combining with, and validation against, borehole and reflection seismic data. To verify the modelling results and to identify uncertainties of AEM inversions and interpretation, we compared the apparent resistivity values of the constructed 3D geological subsurface models with those of AEM field measurements. Our methodology is applied to a test site near Cuxhaven, northwest Germany, where Neogene sediments are incised by a Pleistocene tunnel valley. The Neogene succession is subdivided by four unconformities and consists of fine-grained shelf to marginal marine deposits. At the end of the Miocene an incised valley was formed and filled with Pliocene delta deposits, probably indicating a palaeo-course of the River Weser or Elbe. The Middle Pleistocene (Elsterian) tunnel valley is up to 350 m deep, 0.8–2 km wide, and incised into the Neogene succession. The unconsolidated fill of the Late Miocene to Pliocene incised valley probably formed a preferred pathway for the Pleistocene meltwater flows, favouring the incision. Based on the 3D AEM resistivity model the tunnel-valley fills could be imaged in high detail. They consist of a complex sedimentary succession with alternating fine- and coarse-grained Elsterian meltwater deposits, overlain by glaciolacustrine (Lauenburg Clay Complex) and marine Holsteinian interglacial deposits. The applied approaches and results show a reliable methodology, especially for future investigations of similar geological settings. The 3D resistivity models clearly allow a distinction to be made between different lithologies and enables the detection of major bounding surfaces and architectural elements.
The objective of this field study with an automatic milking system was to evaluate the effects of omitting the dry period on health and productivity during the subsequent lactation in dairy cows. A total of 98 German Simmental cows of six Southern German farms were assigned randomly to two experimental groups: The first group was dried-off 56 days before calving (D for dried-off, n=49), and the second group was milked continuously during this period until calving (CM for continuous milking, n=49). From the latter a third group emerged, including cows that dried-off themselves spontaneously (DS for dried-off spontaneously, n=14). Blood serum values of glucose, β-hydroxybutyrate (BHBA), non-esterified fatty acids (NEFA) and IGF-1 showed most pronounced fluctuations in D cows. Over the entire study period, the concentrations of BHBA and NEFA were markedly lower in the CM and DS groups. Furthermore, IGF-1 concentration was lowest for D cows and also decrease in back fat thickness was more pronounced. Mean concentration of milk protein was markedly higher in CM and DS cows (3.70% and 3.71%) compared with D cows (3.38%). Owing to the lower 305-day milk yield (−15.6%) and the lower total milk yield (−3.1%), the total amount of produced protein in the subsequent lactation was 2.5% (6.8 kg) lower, although the additional protein amount in CM cows from week −8 to calving was 35.7 kg. The greatest benefit resulted from positive effects on fertility and the lower incidence of diseases: CM cows had their first oestrus 1 week earlier compared with D cows, they also conceived earlier and showed a significantly lower risk of developing hypocalcaemia, ketosis and puerperal disorders. The present study showed that the costs of medical treatment and milk losses were twice as high in D cows, compared with CM and DS cows, and thus the reduced costs because of the more stable health outweighed the financial losses of milk yield by +18.49 € per cow and lactation.
We present four wave mixing experiments on GaN. We find an intrinsic homogeneous broadening of the A-exciton of 1.67 meV. A pronounced beating with a period of 0.52 ps is observed at excitation energies between the A- and the B-exciton and corresponds to an energy splitting of 7.98 meV of A- and B-exciton.
Producing high purity aluminum nitride crystals by the sublimation-recondensation technique is difficult due to the inherently reactive crystal growth environment, normally at temperature in excess of 2100 °C. The durability of the furnace fixture materials (crucibles, retorts, etc.) at such a high temperature remains a critical problem. In the present study, the suitability of several refractory materials for AlN crystal growth is investigated, including tantalum carbide, niobium carbide, tungsten, graphite, and hot-pressed boron nitride. The thermal and chemical properties and performance of these materials in inert gas, as well as under AlN crystal growth conditions are discussed. TaC and NbC are the most stable crucible materials with very low elemental vapor pressures in the crystal growth system. Compared with refractory material coated graphite crucibles, HPBN crucible is better for AlN self-seeded growth, as crystals tend to nucleate in thin colorless platelets with low dislocation density.
Epitaxial layers of GaN on c-plane sapphire are analyzed by continuous-wave and time-resolved photoluminescence at 4K and by X-ray diffraction. Besides the well-known emissions from hexagonal GaN we observe luminescence bands at 3.279 and 3.15 to 3.21 eV which are identified as the transition of the donor bound exciton and the donor-acceptor pair recombination in cubic GaN, respectively. Measurements of the luminescence decay times are essential for the clarification of the emission processes. Due to the probing depth of about 200 nm in PL we find that the fraction of cubic phase typically decreases with layer thickness. In our best samples, however, we do not detect the cubic phase at all.
Since early detection of pathogens and their virulence factors contribute to intervention and control strategies, we assessed the enteropathogens in diarrhoea disease and investigated the link between toxigenic strains of Escherichia coli from stool and drinking-water sources; and determined the expression of toxin genes by antibiotic-resistant E. coli in Lagos, Nigeria. This was compared with isolates from diarrhoeal stool and water from Wisconsin, USA. The new Luminex xTAG GPP (Gastroplex) technique and conventional real-time PCR were used to profile enteric pathogens and E. coli toxin gene isolates, respectively. Results showed the pathogen profile of stool and indicated a relationship between E. coli toxin genes in water and stool from Lagos which was absent in Wisconsin isolates. The Gastroplex technique was efficient for multiple enteric pathogens and toxin gene detection. The co-existence of antibiotic resistance with enteroinvasive E. coli toxin genes suggests an additional prognostic burden on patients.