Monoclinic-nondoped and erbium-doped KYb(WO4)2 nanocrystals around 50 nm were synthesized using the modified Pechini sol−gel method. Differential thermal and thermogravimetric analysis (DTA-TG) was ...used to study the thermal evolution of the precursor powder. X-ray powder diffraction (XRD) was used to confirm the presence of the monoclinic phase. We used electron microscopy techniques (SEM and TEM) to observe the morphology and particle size, and we estimated the particle size using Scherrer’s equation. The optical spectroscopy of the trivalent ytterbium and erbium ions in monoclinic KYbW nanocrystals was studied by absorption and emission measurements at low and room temperature. The energy of the Stark sublevel of ytterbium and erbium in the ground- and excited-state KYbW nanocrystals has been determined. After exciting at 940 nm, the green photoluminescence (4S3/2 → 4I15/2) and the 1.5 μm infrared (4I13/2 → 4I15/2) emissions were observed because of the energy transfer from the ytterbium 2F5/2 level to the 4I11/2 erbium level. The decay times of Yb3+ (2F5/2) and Er3+ (4I13/2) excited levels were also studied at room temperature.
Abstract
We construct the largest curved-sky galaxy weak lensing mass map to date from the DES first-year (DES Y1) data. The map, about 10 times larger than the previous work, is constructed over a ...contiguous ≈1500 deg2, covering a comoving volume of ≈10 Gpc3. The effects of masking, sampling, and noise are tested using simulations. We generate weak lensing maps from two DES Y1 shear catalogues, MetaCalibration and Im3shape, with sources at redshift 0.2 < z < 1.3, and in each of four bins in this range. In the highest signal-to-noise map, the ratio between the mean signal to noise in the E-mode map and the B-mode map is ∼1.5 (∼2) when smoothed with a Gaussian filter of σG = 30 (80) arcmin. The second and third moments of the convergence κ in the maps are in agreement with simulations. We also find no significant correlation of κ with maps of potential systematic contaminants. Finally, we demonstrate two applications of the mass maps: (1) cross-correlation
with different foreground tracers of mass and (2) exploration of the largest peaks and voids in the maps.
The intense anti-Stokes white emission of Li(K)P4O12 crystals was observed in vacuum under 808nm excitation. Influence of optical pumping power and ambient pressure on up-conversion properties have ...been investigated. It was found that intense white anti-Stokes white emission occurred at vacuum atmosphere. Its origin has been discussed in terms of Nd2+-charge transfer luminescence occurring at the limited thermal conversion of irradiated crystals in vacuum.
► Bright upconversion emission in Li(K)NdP4O12 crystals in atmospheric pressure was governed by photon avalanche mechanism. ► The intense anti-Stokes white emission of Li(K)NdP4O12 crystals was observed in vacuum under 808nm excitation. ► The mechanism of white emission has been discussed in term of Nd2+-charge transfer luminescence. ► Intensity of anti-Stokes white emission was strongly dependent of surrounding pressure and applied excitation power.
The crystal structure of monoclinic KLu(WO4)2 (KLuW) crystals was determined at room temperature by using single‐crystal X‐ray diffraction data. The unit‐cell parameters were a = 10.576 (7), b = ...10.214 (7), c = 7.487 (2) Å, β = 130.68 (4)°, with Z = 4, in space group C2/c. The unit‐cell parameters of KLu1−xYbx(WO4)2 were determined in relation to Yb concentration. Vickers micro‐indentations were used to study the microhardness of KLuW. The linear thermal expansion tensor was determined and the principal axis with maximum thermal expansion ( = 16.72 × 10−6 K−1), , was located 13.51° from the c axis. The room‐temperature optical tensor was studied in the near‐infrared (NIR) and visible range. The principal optical axis with maximum refractive index (ng = 2.113), Ng, was located 18.5° from the c axis at 632.8 nm. Undoped and ytterbium‐doped KLuW crystals were grown by the TSSG (top‐seeded‐solution growth) slow‐cooling method. The crystals show {110}, {}, {010} and {310} faces that basically constitue the habit of the KLuW crystals.
Based on nationwide data from the French national cancer institute (INCa), we analyzed the evolution of cancer genetics consultations and testing over time, and the uptake of targeted tests in ...relatives of families with BRCA1/2 or MMR genes mutation. Genetic testing and consultations for familial high-risk individuals are exclusively funded and monitored by the INCa in France. All nationwide cancer genetics centers reported annually standardized parameters of activity from 2003 to 2011. The analysis included a total of 240,134 consultations and 134,652 genetic tests enabling to identify 32,494 mutation carriers. Referral for hereditary breast and ovarian cancer (HBOC) or colorectal cancer predisposition syndromes represented 59 % (141,639) and 23.2 % (55,698) consultations, respectively. From 2003 to 2011, we found a dramatic and steady increase of tests performed for BRCA1/2 (from 2,095 to 7,393 tests/year,
P
< 0.0001) but not for MMR genes (from 1,144 to 1,635/year,
P
= NS). The overall percentage of deleterious mutations identified in the probands tested was 13.8 and 20.9 % in HBOC and Lynch syndromes, respectively. Pooled analysis for BRCA1/2 and Lynch syndrome tests showed an inverse relationship between the percentage of mutation detected and the absolute number of tests performed over the time (overall Cochran–Armitage test for trend:
P
< 0.001). In families with BRCA1/2 or MMR identified mutations, there was an average number of 2.94 and 3.28 relatives performing targeted tests, respectively. This nationwide study shows a lack of referral and genetic testing in Lynch as compared to HBOC syndromes. Only a third of relatives of a proband with a predisposing mutation performed a targeted test. Enhanced information about benefit of genetic testing should be given to clinicians and patients for Lynch syndrome and relatives of a proband carrying an identified predisposing mutation.
The destruction of β cells by the islet infiltrating lymphocytes causes type 1 diabetes. Transgenic mice models expressing interferon (IFN)-β in β cells, in the non-obese diabetic (NOD) strain and in ...a diabetes-free, major histocompatibility complex-matched, homologous strain, the non-obese resistant (NOR) mice, developed accelerated type 1 diabetes after 3 weeks of age. Our aim was to determine if natural killer (NK) cells could affect the acceleration of the disease. We determined the amount of NK cells in the pancreas, spleen and lymph nodes from NOD rat insulin promoter (RIP)-IFN-β mice. Pancreatic cytokines were assessed by quantitative real-time polymerase chain reaction and protein arrays. To confirm the relevance of NK cells in the acceleration of autoimmune diabetes this subset was depleted with anti-asialo GM1 antibodies. An increase of intrapancreatic NK cells characterized the accelerated onset of diabetes both in NOD and NOR RIP-IFN-β transgenic models. Cytokines involved in NK function and migration were found to be hyperexpressed in the pancreas from accelerated diabetic mice. Interestingly, the depletion of NK cells in vivo abolished completely the acceleration of diabetes. NK cells connect innate to adaptive immunity and might play a role in autoimmunity. We report here that NK cells are required critically in the pancreas for accelerated diabetes. This model links inflammation to acceleration of β cell-specific autoimmunity mediated by NK cells.
Monoclinic Yb-sensitized (Tm, Ho)-doped KLu(WO4)2 nanocrystals of ~100 nm size have been synthesized by the modified Pechini sol-gel method. Their diode laser near-infrared (~980 nm) excited ...upconversion emission properties have been characterized at power densities in the range 30-355 W cm(-2). Bright white light composed of blue ~475 nm, green ~540 nm, and red ~650 nm emissions, corresponding to Tm(3+ 1)G4 → (3)H6, Ho(3+ 5)S2, (5)F4 → (5)I8, and Ho(3+ 5)F5 → (5)I8 electronic transitions, respectively, was generated by adjusting the Yb, Tm, and Ho contents in KLu(WO4)2 nanocrystalline samples. Chromaticity coordinates of the emitted white light can be tuned by modifying the excitation power density. The effect of Tm and Ho on the luminescence dynamics has been described by analyzing the upconverted emission intensity dependence on the excitation power, as well as from Stokes and decay time measurements. The effect on upconversion properties of further codoping with Eu in these (Tm, Ho, Yb)-doped KLu(WO4)2 nanocrystals has also been studied.
Ant–plant mutualism is widespread and highly diverse in the Neotropics. Several species of arboreal ants can utilize plants as nesting site by colonizing domatia or preformed cavities in tree trunks, ...branches, and stems that have been perforated by wood-boring insects. Arboreal cavity-dwelling ants are a common occurrence, and its effects are well documented, the most studied of which is protection against phytophagous insects. Despite the diversity of cavities in which ants can nest, there are only four published records of colonies inside fruits still attached to trees. Here, we report the occurrence of ant colonies inside mature fruits of
Stryphnodendron adstringens
, which to our knowledge comprises the first formal record of fruit nests at the Brazilian Cerrado, a Neotropical savanna. We encountered five fruits colonized by
Camponotus
sp. and one by
Nesomyrmex spininodis
. Most fruits housed both adult workers and immature ants, except for one fruit that was occupied solely by workers and was attached to the same tree as another that contained larvae. That, and the fact that we did not find any queen, suggest these are polydomous nests. We discuss the possible implications of this association and the knowledge gaps regarding this scarcely studied interaction.
Differences in cerebral activation between control subjects and post-lingually deaf rehabilitated cochlear implant patients were identified with PET under various speech conditions of different ...linguistic complexity. Despite almost similar performance in patients and controls, different brain activation patterns were elicited. In patients, an attentional network including prefrontal and parietal modality-aspecific attentional regions and subcortical auditory regions was over-activated irrespective of the nature of the speech stimuli and during expectancy of speech stimuli. A left temporoparietal semantic region was responsive to meaningless stimuli (vowels). In response to meaningful stimuli (words, sentences, story), left middle and inferior temporal semantic regions and posterior superior temporal phonological regions were under-activated in patients, whereas anterior superior temporal phonological regions were over-activated. These differences in the recruitment of the speech comprehension system reflect the alternative neural strategies that permit speech comprehension after cochlear implantation.
Abstract Background The worldwide seroprevalence of human BK polyomavirus (BKV) in adults is 80%. About 10%–60% of renal transplant recipients experience BKV infection, nephropathy of the graft may ...occur in 5% of the cases, and up to 45% lose the graft. The aim of this work was to describe the prevalence of BK viruria during the 1st year after transplantation. Methods An epidemiologic multicenter cross-sectional study was carried out in consecutive patients at each site with kidney transplantation from August 2011 to July 2012. Clinically significant viruria was defined as >107 copies/mL. Viral DNA was extracted with the use of silica columns. Quantification was performed with the use of real-time polymerase chain reaction with primers that amplify a fragment of the large T-antigen gene and with a specific Taqman-MGB probe for BKV. For each assay, a standard curve with a quantified plasmid was included. Results Of 402 renal transplant recipients at 18 renal transplant sites, we analyzed 382; median age was 46.33 years, and 46.40% were female. The median of the temporal distribution for urine samples was 153 days. BK virus was detected in 50/382 samples (13%), 18 with values >107 copies/mL (4.7%). The median of the distribution of positive values was 123 days and the highest frequency of positive values was in months 3–7. The conditions of recipient older than 34 years and donor older than 41 years were the only ones that showed statistically significant association with BK viruria. No association with any specific immunosuppressive drug was observed. Conclusions This is the first multicenter study conducted in Argentina to determine the prevalence of BK viruria in renal transplant recipients. Because of the growing number of the population susceptible to this infection, it is important to register and describe data about its epidemiology and associated risk factors.
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