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The objective of this study was to determine how much improvement red edge-based vegetation indices (VIs) obtained with the RapidSCAN sensor would achieve for estimating rice nitrogen (N) nutrition index (NNI) at stem elongation stage (SE) as compared with commonly used normalized difference vegetation index (NDVI) and ratio vegetation index (RVI) in Northeast China. Sixteen plot experiments and seven on-farm experiments were conducted from 2014 to 2016 in Sanjiang Plain, Northeast China. The results indicated that the performance of red edge-based VIs for estimation of rice NNI was better than NDVI and RVI. N sufficiency index calculated with RapidSCAN VIs (NSI_VIs) (R2=0.43–0.59) were more stable and more strongly related to NNI than the corresponding VIs (R2=0.12–0.38).
A new cyanolichen, Peltigera islandica sp. nov. in the section Peltigera (‘P. canina group’) is described from Iceland. This species is similar in general appearance to P. rufescens and P. membranacea, but may be recognized by its downturned lobe tips and narrow lobes, respectively. Most thalli are bright emerald green in colour when moist, although a dark khaki green colourmorph is also documented. Monophyly of P. islandica s. lat. (i.e. including P. sp. A sensu O’Brien et al., from Canada) is significantly supported based on ITS sequences and corroborated by molecular synapomorphy (absence of the ITS1 hypervariable region). Analysis of the rbcLX locus indicates the cyanobiont of P. islandica (Nostoc sp.) comprises strains belonging to a pool of Icelandic genotypes, some of which are present in other Peltigera species, including P. “neorufescens”, another taxon new to Iceland collected during this study. Association with photobionts that are shared by other local species suggests P. islandica may be well established in Iceland, but a review of herbarium collections as well as broader field surveys are needed to better characterize its geographical distribution.
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.
China is one of the countries most affected by natural disasters, it is an important restricting factor for economic and social development. However, Disaster Medicine training is not included in medical education curriculum in China, continual training is separated among public health professionals and clinical personals.
WHO provides technical and financial support for public health emergency preparedness through intensive training and workshop. We intended to develop a new working mechanism under the support of WHO and MOH, China for capacity building of disaster preparedness in China with the combination of public health professionals and clinical personals though TOT training.
Through the new mechanism, public health professionals from CDC system and clinical personals from hospitals could benefice mutually fro each side and strengthen the effectiveness for the disaster preparedness.
The new mechanism increases the effectiveness of capacity building for disaster preparedness, TOT training should transit from national level to local level.
Non-destructive Raman spectroscopy was applied to three kinds of porcelain glaze samples: (i) Guan wares of Song Dynasty; (ii) Imitated Guan wares; (Both (i) and (ii) are from the Palace Museum (Beijing, China) collections); (iii) Porcelain shards are collected from the Xiuneisi kiln site which is one of two excavated Guan ware imperial kilns in Hangzhou, the capital of the Southern Song Dynasty. Raman spectra of the glassy phase network were used to discuss the composition and firing temperature of the glaze. The index of polymerization (Ip) is strongly correlated with the firing temperature and the composition of the glaze. According to the Ip values of the glaze, those Guan wares (i) can be classified into three groups. The provenance of Guan wares (i) was discussed by comparing the Ip values to imitations (ii) and shards(iii). The study of classification and provenance are also supported by the X-ray fluorescence data. The Ip values of several recently prepared glazed samples of known firing temperature were measured to build empirical relationship between the Ip value and the firing temperature. Based on the relationship, the firing temperature of the Guan ware glazes was at 1170-1300°C.
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.
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.
The growth temperature and properties of Ge4Sb3Te3 thin films are presented in this paper. The critical growth temperature of Ge4Sb3Te3 is between 300 and 340 °C. The Ge4Sb3Te3 films can only be grown on a substrate below the critical growth temperature. The typical resistivity and carrier density are in the order of 10-4 Ωcm and 1021 cm-3 for crystalline phase. It has a rock salt crystal structure with a lattice constant of 0.602 nm. Ge4Sb3Te3 has a better thermal stability but a lower crystallization speed than Ge2Sb2Te5.
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.
The electron irradiation sensitivities of Pb(Mg1/3Nb2/3)O3 (PMN) and Pb1−xLax[Mg(1+x)/3Nb(2−x)/3]O3 (PLMN) ceramics were investigated by transmission electron microscopy. Nanoscale Pb particles formed in these materials under electron beam radiation. It was found that these fine Pb particles generally had a preferred crystallographic orientation relationship with the PMN/PLMN host and always existed at positions slightly rich in Mg2+. A preliminary mechanism involving defect chemistry reactions is proposed to interpret this unusual Pb precipitation. Possible limitations to the practical applications of these materials are discussed.
A solid polythiophene pellet was ablated by a KrF excimer laser beam to deposit thin films on silicon substrates. The laser-ablated plasma was studied by optical emission spectroscopy to identify the photon-breaking of C–S bonds in the ablated heterocycles. Raman and x-ray photoelectron spectroscopy measurements of the deposited thin films also supported the selective photon-induced bond breaking. After eliminating sulfur in the molecular structures, the thin films appeared to be composed of cubic nanocrystals with a uniform size of 240 nm. X-ray diffraction measurement determined the cubic crystal structures with a lattice constant of α =3.38 Å and suggested a quasi-onedimensional carbon chain structure along the body diagonal of the cube.
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