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A 62-year-old male presented to hospital with acute aphasia. His past medical history was significant for a previous left middle cerebral artery stroke, from which he fully recovered, hypertension, dyslipidemia, coronary artery disease, one episode of atrial fibrillation postoperatively, and thalidomide exposure in utero. Although initially he was thought to be aphasic, on further examination, he demonstrated significant abulia. His level of consciousness was normal, and neurological examination was otherwise unremarkable. A CT angiogram of the head and neck was performed. The patient was not a candidate for acute therapy, as he had established stroke on imaging, and the time of onset was unclear.
Employing atomic-scale simulations, the response of a high-angle grain boundary (GB), the soft/hard GB, against external loading was systematically investigated. Under tensile loading close to the hard orientation, strain-induced dynamic recrystallization was observed to initiate through direct soft-to-hard grain reorientation, which was triggered by stress mismatch, inhibited by surface tension from the soft-hard GB, and proceeded by interface ledges. Such grain reorientation corresponds with expansion and contraction of the hard grain along and perpendicular to the loading direction, respectively, accompanied by local atomic shuffling, providing relatively large normal strain of 8.3% with activation energy of 0.04 eV per atom. Tensile strain and residual dislocations on the hard/soft GB facilitate the initiation of dynamic recrystallization by lowering the energy barrier and the critical stress for grain reorientation, respectively.
The objective of this study was to evaluate the performance of a Crop Circle sensor-based precision nitrogen (N) management (PNM) strategy in different winter wheat cropping systems under on-farm conditions in North China Plain (NCP). Four farmer’s fields were selected for on-farm experiments in Laoling County, Shandong Province of NCP in 2015-2016. In each field, the PNM strategy was evaluated in two winter wheat cropping systems: farmer’s conventional management (FCM) and regional optimum crop management (ROCM). In each cropping system, there were two N management strategies: 1) FCM or ROCM; 2) PNM. The results indicated that the PNM strategy significantly increased partial factor productivity (PFP) by 29% in the FCM system, but did not have any significant improvement in the ROCM system. The ROCM system, using either regional optimum N management or PNM, significantly increased both grain yield and PFP than the FCM system.
The objective of this study was to evaluate the potential of using Multiplex 3, a hand-held canopy fluorescence sensor, to determine rice nitrogen (N) status at different growth stages. In 2013, a paddy rice field experiment with five N fertilizer treatments and two varieties was conducted in Northeast China. Field samples and fluorescence data were collected simultaneously at the panicle initiation (PI), stem elongation (SE), and heading (HE) stages. Four N status indicators, leaf N concentration (LNC), plant N concentration (PNC), plant N uptake (PNU) and N nutrition index (NNI), were determined. The preliminary results indicated that different N application rates significantly affected most of the fluorescence variables, especially the simple fluorescence ratios (SFR_G, SFR_R), flavonoid (FLAV), and N balance indices (NBI_G, NBI_R). These variables were highly correlated with N status indicators. More studies are needed to further evaluate the accuracy of rice N status diagnosis using fluorescence sensing at different growth stages.
The abundance and cross-linking of intramuscular connective tissue contributes to the background toughness of meat, and is thus undesirable. Connective tissue is mainly synthesized by intramuscular fibroblasts. Myocytes, adipocytes and fibroblasts are derived from a common pool of progenitor cells during the early embryonic development. It appears that multipotent mesenchymal stem cells first diverge into either myogenic or non-myogenic lineages; non-myogenic mesenchymal progenitors then develop into the stromal-vascular fraction of skeletal muscle wherein adipocytes, fibroblasts and derived mesenchymal progenitors reside. Because non-myogenic mesenchymal progenitors mainly undergo adipogenic or fibrogenic differentiation during muscle development, strengthening progenitor proliferation enhances the potential for both intramuscular adipogenesis and fibrogenesis, leading to the elevation of both marbling and connective tissue content in the resulting meat product. Furthermore, given the bipotent developmental potential of progenitor cells, enhancing their conversion to adipogenesis reduces fibrogenesis, which likely results in the overall improvement of marbling (more intramuscular adipocytes) and tenderness (less connective tissue) of meat. Fibrogenesis is mainly regulated by the transforming growth factor (TGF) β signaling pathway and its regulatory cascade. In addition, extracellular matrix, a part of the intramuscular connective tissue, provides a niche environment for regulating myogenic differentiation of satellite cells and muscle growth. Despite rapid progress, many questions remain in the role of extracellular matrix on muscle development, and factors determining the early differentiation of myogenic, adipogenic and fibrogenic cells, which warrant further studies.
Despite substantial research, uncertainty remains about the clinical and etiological heterogeneity of major depression (MD). Can meaningful and valid subtypes be identified and would they be stable cross-culturally?
Symptoms at their lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years, with recurrent DSM-IV MD. Latent class analysis (LCA) was performed in Mplus.
Using the nine DSM-IV MD symptomatic A criteria, the 14 disaggregated DSM-IV criteria and all independently assessed depressive symptoms (n = 27), the best LCA model identified respectively three, four and six classes. A severe and non-suicidal class was seen in all solutions, as was a mild/moderate subtype. An atypical class emerged once bidirectional neurovegetative symptoms were included. The non-suicidal class demonstrated low levels of worthlessness/guilt and hopelessness. Patterns of co-morbidity, family history, personality, environmental precipitants, recurrence and body mass index (BMI) differed meaningfully across subtypes, with the atypical class standing out as particularly distinct.
MD is a clinically complex syndrome with several detectable subtypes with distinct clinical and demographic correlates. Three subtypes were most consistently identified in our analyses: severe, atypical and non-suicidal. Severe and atypical MD have been identified in multiple prior studies in samples of European ethnicity. Our non-suicidal subtype, with low levels of guilt and hopelessness, may represent a pathoplastic variant reflecting Chinese cultural influences.
Aberrant functional connectivity within the default network is generally assumed to be involved in the pathophysiology of obsessive compulsive disorder (OCD); however, the genetic risk of default network connectivity in OCD remains largely unknown.
Here, we systematically investigated default network connectivity in 15 OCD patients, 15 paired unaffected siblings and 28 healthy controls. We sought to examine the profiles of default network connectivity in OCD patients and their siblings, exploring the correlation between abnormal default network connectivity and genetic risk for this population.
Compared with healthy controls, OCD patients exhibited reduced strength of default network functional connectivity with the posterior cingulate cortex (PCC), and increased functional connectivity in the right inferior frontal lobe, insula, superior parietal cortex and superior temporal cortex, while their unaffected first-degree siblings only showed reduced local connectivity in the PCC.
These findings suggest that the disruptions of default network functional connectivity might be associated with family history of OCD. The decreased default network connectivity in both OCD patients and their unaffected siblings may serve as a potential marker of OCD.
The symptoms of major depression (MD) are clinically diverse. Do they form coherent factors that might clarify the underlying nature of this important psychiatric syndrome?
Symptoms at lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years with recurrent DSM-IV MD. Exploratory factor analysis (EFA) and confirmatoryfactor analysis (CFA) were performed in Mplus in random split-half samples.
The preliminary EFA results were consistently supported by the findings from CFA. Analyses of the nine DSM-IV MD symptomatic A criteria revealed two factors loading on: (i) general depressive symptoms; and (ii) guilt/suicidal ideation. Examining 14 disaggregated DSM-IV criteria revealed three factors reflecting: (i) weight/appetite disturbance; (ii) general depressive symptoms; and (iii) sleep disturbance. Using all symptoms (n = 27), we identified five factors that reflected: (i) weight/appetite symptoms; (ii) general retarded depressive symptoms; (iii) atypical vegetative symptoms; (iv) suicidality/hopelessness; and (v) symptoms of agitation and anxiety.
MD is a clinically complex syndrome with several underlying correlated symptom dimensions. In addition to a general depressive symptom factor, a complete picture must include factors reflecting typical/atypical vegetative symptoms, cognitive symptoms (hopelessness/suicidal ideation), and an agitated symptom factor characterized by anxiety, guilt, helplessness and irritability. Prior cross-cultural studies, factor analyses of MD in Western populations and empirical findings in this sample showing risk factor profiles similar to those seen in Western populations suggest that our results are likely to be broadly representative of the human depressive syndrome.
An introduction to gravitational wave astronomy and detectors
D. G. Blair, University of Western Australia,
L. Ju, University of Western Australia,
C. Zhao, University of Western Australia,
H. Miao, California Institute of Technology,
E. J. Howell, University of Western Australia,
P. Barriga, University of Western Australia
D. G. Blair, University of Western Australia, Perth,E. J. Howell, University of Western Australia, Perth,L. Ju, University of Western Australia, Perth,C. Zhao, University of Western Australia, Perth
This chapter first introduces gravitational wave detection from a very general point of view, before looking at the particular methods of detection across the spectrum from nanohertz to kilohertz. It finishes by focusing specifically on terrestrial laser interferometers.
The discovery of radio waves by Heinrich Hertz in 1886 unleashed the communications revolution which has transformed our lives. Optimisation of radio receivers required understanding and integration of two concepts. The first was the concept of the antenna, which taps energy from a wave freely propagating in space and converts it into a signal which can be amplified and detected. The second was the receiver, which processes this energy by detection (converting it to a slowly time-varying voltage), amplification (increasing its amplitude without changing its frequency) or modulation (changing its frequency).
Designing gravitational wave receivers is analogous to designing radio receivers, except that electric charges moving freely in conductors are replaced by test masses floating freely in space. This concept was illustrated in Figure 1.2 in Chapter 1, showing how a ring of test particles is deformed by a passing gravitational wave. The first gravitational wave receivers were constructed by Joseph Weber in the 1960s. They took the form of large test masses in which gravitational waves could induce quadrupole vibrations. Weber went on to develop the Weber bar, in which one searched for excitations in the fundamental longitudinal vibrational mode of a cylinder. In this case, the receiver can be idealised as a pair of point masses joined by a mechanical spring.
We compared the hydrogen uptake weight percentages (wt.%) of different
carbonized materials, before and after modification, for their application
in hydrogen storage at room temperature. The Sievert's method [T.P. Blach, E. Mac, A. Gray, J. Alloys Compd. 446-447, 692 (2007)] was used
to measure hydrogen uptake values on: (1) Taiwan bamboo charcoal (TBC), (2)
white charcoal (WC), (3) single-walled carbon nanotubes (SWCNTs) bought from
CBT Inc. and (4) homemade multi-walled carbon nanotubes (MWCNTs) grown on
TBC. Modified samples were coated with a metal catalyst by dipping in KOH
solutions of different concentrations and then activated in a high
temperature oven (800 °C) under the atmospheric pressure of inert
gas. The results showed that unmodified SWCNTs had superior uptake but that
Taiwan bamboo charcoal, after modification, showed enhanced uptake
comparable to the SWCNTs. Due to TBC's low cost and high mass production
rate, they will be the key candidate for future hydrogen storage
We sought to determine whether a standardized emergency department (ED) asthma care pathway (ACP) for adults would be accepted by ED staff, improve adherence to Canadian ED asthma management guidelines and improve patient outcomes.
Ten Ontario hospital EDs (5 intervention, 5 control) participated in a 5-month pre–post intervention study. Emergency department management, admissions, repeat ED visits and ED length of stay were compared between sites and by ACP use versus nonuse at intervention sites.
The ACP was used in 101 of 383 visits (26.4%) at 5 intervention sites. Use of the ACP varied significantly between sites, ranging from 6% to 60% (p < 0.001). When compared with control sites, there were significant increases in the use of metered dose inhalers (MDIs), inhaled steroids, referrals, documentation of teaching, patient recollection of teaching (all with a p < 0.001) and oxygen (p = 0.001). Use of peak expiratory flow rate (PEFR) measurements decreased in both intervention and control sites. Increased PEFR documentation and systemic steroid use in the ED and on discharge were only found in patients who were on the ACP at intervention sites. Admissions increased from 3.9% to 9.4% at intervention sites in contrast to control sites, where they remained fairly stable (p = 0.016), but did not differ by ACP use. The length of stay for discharged patients increased by a mean of 16 minutes for ACP patients at intervention sites (p = 0.002). There were no statistically significant differences in repeat ED visits.
Adoption of a standardized ED ACP for adults is highly variable. Despite modest uptake, which averaged 26%, beneficial changes in specific aspects of asthma care delivery were found, notably in referrals and recollection of teaching done during the ED visit, without a substantial increase in ED length of stay. These changes may lead to improvements in outcomes, such as reduced relapse rates, which this study was not designed or powered to detect. Provincial and national implementation strategies that address barriers to clinical pathway adoption are warranted and have the potential to improve adherence to guidelines and outcomes for asthma patients.
The present study was aimed to compare the developmental changes of carcass composition, meat quality characteristics and organ weight in pigs of different breeds. Six pigs (sex balance) of each breed were slaughtered at 35, 80 and 125 days of age, respectively. The carcass was chilled and the left carcass side was dissected into bone, lean meat, fat and skin; additionally, organ weight and meat quality parameters were observed. Carcasses of the Jinhua pig were lighter (P < 0.001), contained less lean meat percentage (P < 0.01) and more carcass fat percentage (P < 0.05) than did carcasses of the Landrace. L*-values were lower in Jinhua pigs than in Landrace at 125 days of age (P < 0.05), but the Jinhua pig had higher a*-values compared with Landrace at the age of 80 days (P < 0.01) and 125 days (P < 0.01), respectively. In addition, Jinhua pigs showed lower colour scores (P < 0.05), higher intramuscular fat (IMF) percentage (P < 0.05), less marbling scores (P < 0.05) and lower drip loss (P < 0.05) than Landrace. For organ weight, Jinhua pigs had higher relative heart weight at the age of 80 days (P < 0.05) and 125 days (P < 0.001), and higher relative liver weight at 125 days of age (P < 0.01) than that of Landrace. In addition, the relative kidney weight was heavier (P < 0.001) in the Jinhua pig than in the Landrace during the whole experiment. These results indicated that developmental changes of carcass composition, meat quality parameters and organ weight displayed breed differences. Jinhua pigs were fatter than Landrace but the former had better quality characteristics in the meat.
This article presents current R&D activities at Observatoire de Paris – Laboratoire d'Etude du Rayonnement
et de la Matière en Astrophysique in the fields of low noise mixers and local oscillators for heterodyne instruments dedicated to astrophysics, planetology and the sciences of the atmosphere.
HfO2 films were grown on SiO2/4H-SiC and SiON/4H-SiC layers by evaporation of metallic Hf in an electron beam deposition system followed by thermal oxidation. X-ray photoelectron spectroscopy confirmed the formation of HfO2 films. There is no evidence of formation of hafnium silicide or carbon pile up at the surface as well as at the interfacial layer. Electrical measurements show the presence of fewer slow traps in the HfO2/SiON gate dielectric stack on 4H-SiC and comparable values of interface state density. The HfO2/SiON stack layer improves leakage current characteristics with a higher breakdown field and has better reliability under electrical stress.
The excitation intensity dependency of nanocrystallite Si (nc-Si) related micro-photoluminescence (μ-PL) from the multi-recipe Si-implanted quartz is characterized. The μ-PL at 724 nm contributed by nc-Si with 3-4 nm diameter is maximized after annealing at 1100°C for 3 hours. By increasing the excitation intensity from 10 kW/cm2 to 300 kW/cm2, the μ-PLs of 1-hr and 3-hr annealed quartz significantly red-shift from 723 nm to 725 nm and from 724 nm to 735 nm, respectively. This can be explained by the anomalous quantum stark effect due to a surface electric field oriented from photo-ionized nc-Si dots to quartz surface. After 1-hr illumination at power of 300 kW/cm2, the μ-PL peak wavelength of 3-hr annealed sample is further red-shifted by 2.5 nm. By measuring the accumulated surface charges built up during optical excitation process, the correlation between excitation-intensity dependent PL wavelength red-shift and the photo-ionized nc-Si surface electric-field related quantum stark effect is primarily elucidated.
Direct ceramic stereolithography (SLA) is done using UV-curable suspensions of powders in acrylates in a conventional SLA machine. Hydroxyapatite prototypes for bone tissue scaffolds are built from Image-Based Design files, featuring an interior architecture of void passages. Complex alumina objects are built as digital sculptures. Piezoelectric ceramic actuators from PZT, which are difficult to photocure, are built using indirect stereolithography, where SLAbuilt epoxy molds are used to form a thermal-cured suspension of PZT powders. We report on the thermal-curing behavior of the suspensions, and the fundamentals of part building.
Nitrogen is the most common limiting factor in the growth and productivity of plants. Legume plants, however, have overcome this limitation by developing the ability to harbour a group of soil bacteria (Azorhizobium, Bradyrhizobium, Rhizobium and Sinorhizobium spp.) in a symbiotic association. In this mutually beneficial interaction, bacteria invade the root cells of host plants where they become intracellular ‘organelles’ called bacteroids and are able to fix atmospheric dinitrogen into ammonium for assimilation by the plant. To facilitate this process, the host plant develops an entirely new organ, a root nodule, which houses the nitrogen-fixing bacteria and provides the carbon sources, other nutrients and appropriate environment to support the reduction of dinitrogen (see Verma & Long, 1983; Long, 1989; Verma & Stanley, 1989).
The Rhizobium–legume symbiosis, an interaction between a prokaryote (Rhizobium) and a eukaryote (legume), requires a series of sequential induction and function of both bacterium-encoded (bacteroidins) and host-encoded (nodulins) nodule-specific proteins. It has been shown that many plant (Peters et al., 1986; Firmin et al., 1986; Djordjevic et al., 1987; Sadowsky et al., 1988; see also Peters & Verma, 1990) and bacterial (Lerouge et al., 1990; Kondorosi, 1991) signals are involved in the induction of specific genes leading to the development of the root nodule. Many bacterial mutations blocking root hair deformation, induction of cortical cell division, infection thread formation and subsequent events leading to the endocytotic release of bacteria inside the host cell are known (see Rolfe & Shine, 1984).
Si3N4 ceramics are excellent metal cutting materials. The cutting behavior can be improved by hard particle dispersion phase hardening and heat treatment so as to reduce glass phase in the grain boundaries. Compared with cemented carbide tools, the cutting life of the composite Si3N4 cutting tool is about 10-100 times longer, and the optimum cutting speed is about 3-10 times faster. It performs well in cutting hardened tools, nickel based alloys, and other hard materials and can sustain shock loads in operations such as milling, planing and other types of interrupted cutting. Applications in various fields show that machining efficiency can be increased by 3-10 times resulting in savings of time, electricity, and machining of 30-70% or even more.
The non-resonant third order nonlinearity of conjugated polymers appears to
be potentially useful for all-optical devices in waveguide formats.[l,2]
This nonlinearity manifests itself as an intensity-dependent refractive
index which leads to a nonlinear phase shift over some propagation distance.
Device research over the last few years has shown that there are certain
minimum requirements for the nonlinear phase shift that need to be achieved
over one absorption length of the material.[l,3] There are two principal
sources of absorption, the usual linear absorption which is independent of
fluence, and two photon absorption for which the absorption scales linearly
with intensity. Thus the usefulness of a nonlinear material for all-optical
switching devices can be evaluated from a limited number of material
parameters, namely n2 (in n = n0 + n2I
where I is the local intensity), α0 which is the low power
absorption coefficient and β which is the two photon
coefficient (in α = α0 + βI). The problem for a
given material is to identify spectral regions over which the minimum
required phase shift can be achieved.
This report will try to review briefly the work achieved from 1982 to 1984 in different “subjects to be considered by Commission 31 Time” as adopted in Grenoble 1976. It contains also information provided by Commission members, for which hearty thanks are to be given. The limitation of space required the abbrevation of some institution reports.
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