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Introduction: White matter hyperintensities (WMHs) were commonly seen in brain magnetic resonance imaging (MRI) of the elderly. Many studies found that WMHs were associated with cognitive decline and dementia. However, the association between WMHs in different brain regions and cognitive decline remains debated. Methods: We explored the association of the severity of WMHs and cognitive decline in 115 non-demented elderly (≥50 years old) sampled from the Wuliqiao Community located in urban area of Shanghai. MRI scans were done during 2009–2011 at the beginning of the study. Severity of WMHs in different brain regions was scored by Improved Scheltens Scale and Cholinergic Pathways Hyperintensities Scale (CHIPS). Cognitive function was evaluated by Mini-Mental State Examination (MMSE) every 2 to 4 years during 2009–2018. Results: After adjusting for confounding factors including age, gender, education level, smoking status, alcohol consumption, depression, hypertension, diabetes, hyperlipidemia, brain infarcts, brain atrophy, apoE4 status, and baseline MMSE score, periventricular and subcortical WMH lesions as well as WMHs in cholinergic pathways were significantly associated with annual MMSE decline ( p < 0.05), in which the severity of periventricular WMHs predicted a faster MMSE decline (–0.187 points/year, 95% confidence interval: –0.349, –0.026, p = 0.024). Conclusions: The severity of WMHs at baseline was associated with cognitive decline in the non-demented elderly over time. Interventions on WMH lesions may offer some benefits for cognitive deterioration.
To revise an abbreviated version of the Silhouettes subtest of the Visual Object and Space Perception (VOSP) battery in order to recognize mild cognitive impairment (MCI) and determine the optimal cutoffs to differentiate among cognitively normal controls (NC), MCI, and Alzheimer’s Disease (AD) in the Chinese elderly.
A cross-sectional validation study.
Huashan Hospital, Shanghai, China.
A total of 591 participants: Individuals with MCI (n = 211), AD (n = 139) and NC (n = 241) were recruited from the Memory Clinic, Huashan Hospital, Shanghai, China.
Baseline neuropsychological battery (including VOSP) scores were collected from firsthand data. An abbreviated version of silhouettes test (Silhouettes-A) was revised from the original English version more suitable for the elderly, including eight silhouettes of animals and seven silhouettes of inanimate objects, with a score ranging from 0 to 15.
Silhouettes-A was an effective test to screen MCI in the Chinese elderly with good sensitivity and specificity, similar to the Montreal cognitive assessment and superior to other single tests reflecting language, spatial, or executive function. However, it had no advantage in distinguishing MCI from AD. The corresponding optimal cutoff scores of Silhouettes-A were 10 for screening MCI and 8 for AD.
Silhouettes-A is a quick, simple, sensitive, and dependable cognitive test to distinguish among NC, MCI, and AD patients.
A Basic Angle (BA) of 106.5° separates the view directions of Gaia's two fields of view (FoV). A precise determination of the BA variations (BAV) is essential to guarantee a correct reconstruction of the global astrometric sphere, as residual systematic errors would result in, e.g., a bias in the parallaxes of the final Gaia catalog. The Basic Angle Monitoring (BAM) device, which provides a reliable and accurate estimation of BAV, shows that there exists a ~1 mas amplitude, 6-h period BA oscillation. It's essential to verify to what extent this signal is caused by real BAV, or is at least in part an effect of the BAM device itself. Here, we propose an astrometric on-sky approach to re-determine the 6-h periodic BAV. The results of this experiment, which treated a full day (17 Oct 2016) of Gaia astrometric data, recover a value for the 6-h oscillation of 1.856±0.857 mas. This is consistent, within the errors, with the BAM finding for that day.
The autonomous navigation of navigation and positioning systems such as the Global Positioning System (GPS) and other Global Navigation Satellite Systems (GNSS) was motivated to improve accuracy and survivability of the navigation function for 180 days without ground contact. These improvements are accomplished by establishing inter-satellite links in the constellation for pseudo-range observations and communications between satellites. But observability issues arise for both ephemeris and clock since the pseudo-range describes only the relative distance between satellites. A differential measurement method is proposed to measure the rotation of the constellation as a whole for the first time. The feasibility of the proposed method is verified by simulations.
The etiology and pathogenesis of neurodegenerative disorders has yet to be elucidated, so their differential diagnosis is a challenge. This is especially true in differentiating Alzheimer's disease (AD), dementia with Lewy bodies (DLB), Parkinson disease (PD), and multiple system atrophy (MSA).
A total of 11 eligible articles were identified by search of electronic databases including PubMed, Springer Link, Elsevier, and the Cochrane Library, up to June 2014. In meta-analyses, standardized mean differences (SMD), with 95% confidence intervals (CI), comparing cerebrospinal fluid (CSF) measures of α-synuclein between the above conditions were calculated using random-effects models.
CSF α-synuclein concentrations were significantly higher in AD compared to DLB [SMD: 0.32, 95% CI: (0.02, 0.62), z = 2.07, P = 0.038]; PD [SMD: 0.87, 95% CI: (0.15, 1.58), z = 2.38, P = 0.017]; or MSA [SMD: 1.14, 95% CI: (0.15, 2.14), z = 2.25, P = 0.025]. However, no significant difference was found between patients with AD and neurological cognitively normal controls [SMD: 0.02, 95% CI: (−0.21, 0.24), z = 0.13, P = 0.894].
Results of these meta-analysis suggest that quantification of CSF α-synuclein could help distinguish AD from other neurodegenerative disorders such as DLB, PD, or MSA.
A high molecular weight protein (HMWP) was isolated and purified from sow milk, and some of its biochemical characteristics and biological functions were identified. The origin of HMWP was also investigated. The molecular weight of HMWP was determined to be about 115 000 and 114 800 by SDS-PAGE and gel filtration, respectively. The sequence of 10 amino acids in N-terminal of HMWP was Ala-Leu-Val-Gln-Ser-Cys-Leu-Asn-Leu-Val. The sequence was blasted against GenBank. No protein showed significant similarity with this sequence suggesting the HMWP may be novel. The result of liquid chromatography mass spectrometry (LC-MS) also proved HMWP could be a novel protein. By amino acid assay, HMWP was rich in glutamate (including glutamine), cysteine, glycine, aspartic acid (including asparagines) and proline. The content of hydrophobic amino acids (Ala, Val, Leu, Ile, Met, Phe and Pro) was lower at 18.59% of the total amino acids suggesting HMWP has high solubility in water. Western blots of lectins were used to identify the kinds of carbohydrate residues attached to HMWP qualitatively. The result showed that HMWP was a kind of glycoprotein containing N-acetylneuraminic acid (NeuNAc), mannose (Man) and/or N-acetylglucosamine (GlcNAc). By isoelectric focusing, HMWP pI was found to be 5.1. Compared with milk fat globule membrane protein (MFGMP) isolated from the sow milk in SDS-PAGE, MFGMP did not contain HMWP. HMWP was assumed to be a secretory milk protein. HMWP was not found in bovine, goat, rabbit or human milk in SDS-PAGE gel suggesting HMWP may be unique to sow milk. By Western blot, HMWP could be detected in sow milk, not in sow serum, which suggests it is synthesized and secreted by the mammary gland. HMWP concentrations in sows milk were the lowest in the first day of lactation, rose significantly during lactation 1 to 7 days. The HMWP content of sows milk remained relatively constant ((1.95±0.13) g/l) during lactation 7 to 20 days. HMWP significantly inhibited Escherichia coli in a dose related manner in vitro. Overall, HMWP could be a novel sow milk protein with implications for the mammary gland and the piglet.
To assess correlations between cruciferous vegetable intake and urinary isothiocyanate (ITC) level, in addition to glutathione S-transferase (GST) genotypes and other individual factors.
The study included cohort participants whose urinary ITC levels had been previously ascertained. Urinary ITC was assessed using HPLC. Usual dietary intake of cruciferous vegetables was assessed using a validated FFQ and total dietary ITC intake was calculated. Recent cruciferous vegetable intake was determined. GST genotypes were assessed using duplex real-time quantitative PCR assays. Spearman correlations were calculated between the covariates and urinary ITC levels and linear regression analyses were used to calculate the mean urinary ITC excretion according to GST genotype.
Urban city in China.
The study included 3589 women and 1015 men from the Shanghai Women’s and Men’s Health Studies.
Median urinary ITC level was 1·61 nmol/mg creatinine. Self-reported usual cruciferous vegetable intake was weakly correlated with urinary ITC level (rs=0·1149; P<0·0001), while self-reported recent intake was more strongly correlated with urinary ITC (rs=0·2591; P<0·0001). Overall, the GST genotypes were not associated with urinary ITC level, but significant differences according to genotype were observed among current smokers and participants who provided an afternoon urine sample. Other factors, including previous gastrectomy or gastritis, were also related to urinary ITC level.
The study suggests that urinary secretion of ITC may provide additional information on cruciferous vegetable intake and that GST genotypes are related to urinary ITC level only in some subgroups.
Potassium dihydrogen phosphate (KDP) single crystals are the only nonlinear crystals currently used for electro-optic switches and frequency converters in inertial confinement fusion research, due to their large dimension and exclusive physical properties. Based on the traditional solution-growth process, large bulk KDP crystals, usually with sizes up to 600
so as to make a frequency doubler for the facility requirement loading highly flux of power laser, can be grown in standard Holden-type crystallizers, without spontaneous nucleation and visible defects, one to two orders of magnitude faster than by conventional methods. Pure water and KDP raw material with a few ion impurities such as Fe, Cr, and Al (less than 0.1 ppm) were used. The rapid-growth method includes extreme conditions such as temperature range from 60 to 35
C, overcooling up to 5
C, growth rates exceeding 10 mm/day, and crystal size up to 600 mm. The optical parameters of KDP crystals were determined. The optical properties of crystals determined indicate that they are of favorable quality for application in the facility.
In insect, fat body plays major roles in insect innate immunity. Phenoloxidase (PO) is an important component in insect innate immunity and is necessary for acclimatization. In our study, two prophenoloxidase (PPO) subunits were obtained from fat body of Catantops pinguis (Stål). The full-length cDNA sequence of one PPO (CpPPO1) consisted of 2347 bp with an open reading frame (ORF) of 2187 bp encoding 728 amino acids, while the other subunit (CpPPO2) had a full length of 2445 bp, encoding 691 amino acids. Both the PPO gene products are predicted to possess all the structural features of other PPO members, including two putative tyrosinase copper-binding motifs with six highly conserved histidine residues and a thiolester-like motif. Tissue distribution analysis showed that both PPO mRNAs were abundantly expressed in the fat body among 11 tissues examined, and they were transiently up-regulated after Escherichia coli infection, consistent with them being immune-responsive genes. Total levels of CpPPO1 and CpPPO2 mRNA transcripts were much higher in first instar larvae and adults. A much higher transcript level of CpPPO1 was detected in several months, while there were extremely high mRNA expression levels of CpPPO2 in January, July, October, and December. The above results suggested that PPO from fat body might also bring significant function during the processes of development and acclimatization for C. pinguis.
Most of the discovered exoplanets are close to our sun. Usually their host star is with large proper motions, which is an important parameter for exoplanet searching. The first version of absolute proper motions catalog achieved based on Digitized Sky Survey Schmidt plate where outside the galactic plane |b|≥27° is presented, resulting in a zero point error less than ± 0.3 mas/yr, and the overall accuracy better than ± 4.5 mas/yr for objects brighter than RF=18.5, and ranging from 4.5 to 9.0 mas/yr for objects with magnitude 18.5<RF<20.5. The systematic errors of absolute proper motions related to the position, magnitude and color are practically all removed. The sky cover of this catalog is 22,525 degree2, the mean density is 6444 objects/degree2 and the magnitude limit is around RF=20.5.
We give a new method for calculating the Γ-limit functional encountered in the problems of homogenisation. We use the Legendre–Lagrange transform in the convex analysis and regularisation method to obtain the explicit expression of the Γ-limit functional. The result can be applied to some nonlocal function spaces.
In this paper, we study all the stationary solutions of the form u(r)einθ to the complex-valued Ginzburg–Landau equation on the complex plane: here (r, θ) are the polar coordinates, and n is any real number. In particular, we show that there exists a unique solution which approaches to a nonzero constant as r → ∞.
This paper gives a sufficient condition for almost-everywhere injectivity for nonlinear three dimensional elasticity similar to that of Claret-Necas , namely.
We prove that this relation is maintained under the weak convergence of minimising sequences for nonlinear elasticity problems. The existence and partial regularity of an “inverse” function are proved.
For field-induced electron emission, the two factors that enable a high emission current density at low applied voltages are (a) low work function of the emitter and (b) sharpness of the emitter tip. We have developed and applied a chemical vapor deposition method to synthesize single-crystalline LaB6 nanowires for applications as point electron emitters. The crystallographic orientation of the grown nanowires can be controlled by the catalysts used in synthesis and their typical diameter is ranged from below 20 nm to over 100 nm. The nanowires’ tip is either hemispherical or flat top with rectangular cross-section depending on the catalyst being utilized. The field emission properties have also been measured from the single nanowire emitters and the results are discussed for applications as point electron sources used in high performance electron optical instruments such as the transmission and scanning electron microscopes.
A simple novel route to synthesize aqueous tantalum and niobium precursors has been developed using cheap and stable Nb2O5 or Ta2O5 as starting source, based on basic flux technique. Various analytical techniques have been employed to characterize the purity, and thermal decomposition features of the precursors. Using home-made Ta and Nb precursors, several photocatalysts and ferroelectric powders such as LiNbO3, LiTaO3, Sr0.75Ba0.25Nb2O6, and SrBi2Ta2O9 have been prepared at lower processing temperature by a polymerizable complex route successfully.
As the industry develops processes for the 65 and 45 nm technology nodes, post etch/ash cleaning faces new challenges with far more stringent requirements on surface cleanliness and materials loss. The introduction and integration of new materials, such as metal hard mask, creates additional requirements for wafer cleaning due to the occurrence of new defect modes related to metal hard mask. These include organometallic residue and metal fluorite compounds precipitating with time. We have developed a novel aqueous solution (AQ) based single wafer cleaning process to address these new defect modes. Physical characterization results and process integration electrical data and reliability data (TEM cross section review of the vias) are presented in this paper.
The main conclusions can be summarized as follows: (1) In the dual damascene Cu/low-k process flow with hard mask, there are three typical residues after etch/ash: generic polymer residue, organometallic residue strongly bonded to metal maks, and time-dependent metal fluoride residue. (2) Generic polymer residue is very well characterized [1,2] and is usually easy to remove with solvent or aqueous solution [2,3]. (3)We developed an oxidizing chemistry based process to undercut the hard mask for the organometallic residue removal, which proved highly effective. (4)The time-dependent metal fluoride reside makes queue time control after etch/ash very critical (<1 hour). We developed a process with a fluorine based aqueous chemistry to address the metal fluoride residue, which proved highly effective. With this new process, queue time control is not required. (5) The post etch/ash cleaning for the Cu/low-k structure with metal hard mask typically employs the solvent/dry plasma ash multi-step procedure . The new process developed in this research reduced the multi-step process to one wet clean step with two different aqueous chemistries in sequence. (6) The integration electrical data shows that the new single step aqueous cleaning process performance is comparable to, or even better than that from the solvent/dry plasma ash multi cleaning process. (7) Blanket Cu loss with the new process is about 23A/min, however TEM analysis of the vias after full integration shows Cu loss, we are working to improve the integration related Cu loss.
Using microsatellite markers, the genetic structure of nine domestic duck (Anas platyrhynchos) populations in eastern China was analysed. The results showed that the heterozygosity was high in these populations, ranging from 0.5137 to 0.6055, with an average heterozygosity of 0.5523, reflecting the rich diversity. Considerable breed differentiation was observed and 25.65% of the total genetic variation came from breed differences; this low differentiation result affirmed that each breed has its own genetic diversity. The DA genetic distances suggested that greater differentiation existed between populations. The duck populations were clustered into four groups based on neighbour joining (NJ) clustering, and the clustering results showed relationships with duck breed distributions and economic utilization.
Geochemical and Sr–Nd–Pb isotopic data are presented for volcanic rocks from Zougouyouchaco (30.5 Ma) and Dogai Coring (39.7 Ma) of the southern and middle Qiangtang block in northern Tibet. The volcanic rocks are high-K calc-alkaline trachyandesites and dacites, with SiO2 contents ranging from 58.5 to 67.1 wt % The rocks are enriched in light REE (LREE) and contain high Sr (649 to 986 ppm) and relatively low Yb (0.8 to 1.2 ppm) and Y (9.5 to 16.6 ppm) contents, resulting in high La/Yb (29–58) and Sr/Y (43–92) ratios, as well as relatively high MgO contents and Mg no., similar to the compositions of adakites formed by slab melting in subduction zones. However, the adakitic rocks in the Qiangtang block are characterized by relatively low εNd(t) values (−3.8 to −5.0) and highly radiogenic Sr ((87Sr/86Sr)i=0.706–0.708), which are inconsistent with an origin by slab melting. The geochemistry and tectonics indicate that the adakitic volcanic rocks were most likely derived from partial melting of delaminated lower continental crust. As the pristine adakitic melts rose, they interacted with the surrounding mantle peridotite, elevating their MgO values and Mg numbers.
To make GSC-II more accurate and useful, it is necessary to re-calibrate GSC-II when a better reference catalogue (UCAC2) is available. With UCAC2 as the reference, preliminary re-calibration of some sample plates from GSC2.3 were carried out with different methods, such as Global, Mask and Filter. The results indicate that a 7th-order polynomial is sufficient to account for the influence of Schmidt plate deformation on the measured coordinates of stars. The magnitude equation can be eliminated after correcting for a common magnitude equation. The RMS of the re-calibrated data is around ±0.2~0.3 arcsec.
The main optical instruments of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) are installed separately. Guiding is realized by adjusting the normal direction of the mirror MA. In order to keep the central star imaged on the rotation center of the fiber plug plate, the link between celestial and fiber plug plate coordinate systems has to be established. Some local parameters contain errors so that the normal direction of the MA calculated beforehand may not be accurate enough. The execution error of the telescope also drives the image of the central star to deviate from the rotation center. Therefore, in the process of observations the correction has to be calculated and applied periodically. Here we present the method of calculating the guiding parameters as well as the correction parameters for the LAMOST.