260 research outputs found
Why I Am Optimistic about My Post PhD-degree Life – A Commentary
Public health is an area where we will always need professionally-prepared people. Whereas some soon-to-be graduates are concerned about their future job prospects, others express optimism, undeterred by the economic downturn of the past five years and the funding challenges that currently burden higher education. Staying focused and finding the right niche may be the key to a successful future
Enantioselective, Stereodivergent Hydroazidation and Hydroamination of Allenes Catalyzed by Acyclic Diaminocarbene (ADC) Gold(I) Complexes
The gold-catalyzed enantioselective hydroazidation and hydroamination reactions of allenes are presented herein. ADC gold(I) catalysts derived from BINAM were critical for achieving high levels of enantioselectivity in both transformations. The sense of enantioinduction is reversed for the two different nucleophiles, allowing access to both enantiomers of the corresponding allylic amines using the same catalyst enantiomer
An fMRI investigation of the effects of attempted naming on word retrieval in aphasia
In healthy controls, picture naming performance can be facilitated by a single prior exposure to the same picture ("priming"). This priming phenomenon is utilized in the treatment of aphasia, which often includes repeated picture naming as part of a therapeutic task. The current study sought to determine whether single and/or multiple exposures facilitate subsequent naming in aphasia and whether such facilitatory effects act through normal priming mechanisms. A functional magnetic resonance imaging paradigm was employed to explore the beneficial effects of attempted naming in two individuals with aphasia and a control group. The timing and number of prior exposures was manipulated, with investigation of both short-term effects (single prior exposure over a period of minutes) and long-term effects (multiple presentations over a period of days). Following attempted naming, both short-term and long-term facilitated items showed improvement for controls, while only the long-term condition showed benefits at a behavioral level for the participants with aphasia. At a neural level, effects of long-term facilitation were noted in the left precuneus for one participant with aphasia, a result also identified for the equivalent contrast in controls. It appears that multiple attempts are required to improve naming performance in the presence of anomia and that for some individuals with aphasia the source of facilitation may be similar to unimpaired mechanisms engaged outside the language network
Defining the genetic susceptibility to cervical neoplasia - a genome-wide association study
Funding: MAB was funded by a National Health and Medical Research Council (Australia) Senior Principal Research Fellowship. Support was also received from the Australian Cancer Research Foundation. JL holds a Tier 1 Canada Research Chair in Human Genome Epidemiology. The Seattle study was supported by the following grants: NIH, National Cancer Institute grants P01CA042792 and R01CA112512. Cervical Health Study (from which the NSW component was obtained) was funded by NHMRC Grant 387701, and CCNSW core grant. The Montreal study was funded by the Canadian Institutes of Health Research (grant MOP-42532) and sample processing was funded by the Reseau FRQS SIDA-MI. The Swedish Research Council, the Swedish Foundation for Strategic Research, the ALF/LUA research grant in Gothenburg and Umeå, the Lundberg Foundation, the Torsten and Ragnar Soderberg’s Foundation, the Novo Nordisk Foundation, and the European Commission grant HEALTH-F2-2008-201865-GEFOS, BBMRI.se, the Swedish Society of Medicine, the KempeFoundation (JCK-1021), the Medical Faculty of Umeå University, the County Council of Vasterbotten (Spjutspetsanslag VLL:159:33-2007). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscriptPeer reviewedPublisher PDFPublisher PD
Achiral dielectric metasurfaces for spectral and polarization control of valley specific light emission from monolayer MoS2
Excitons in two-dimensional transition metal dichalcogenides have a valley
degree of freedom that can be optically accessed and manipulated for quantum
information processing. Here, we integrate MoS2 with achiral silicon disk array
metasurfaces to enhance and control valley-specific absorption and emission.
Through the coupling to the metasurface Mie modes, the intensity and lifetime
of the emission of neutral excitons, trions and defect bound excitons can be
enhanced, while the spectral shape can be modified. Additionally, we
demonstrate the symmetric enhancement of the degree-of-polarization (DOP) of
neutral exciton and trions via valley-resolved PL measurements, and find that
the DOP can be as high as 24% for exciton emission and 34% for trion emission
at 100K. These results can be understood by analyzing the near-field impact of
metasurface resonators on both the chiral absorption of MoS2 emitters as well
as the enhanced emission from the Purcell effect. Combining Si-compatible
photonic design with large-scale (mm-scale) 2D materials integration, our work
makes an important step towards on-chip valleytronic applications approaching
room-temperature operation
Interval breast cancer rates for digital breast tomosynthesis versus digital mammography population screening: An individual participant data meta-analysis
Background: Digital breast tomosynthesis (DBT) improves breast cancer (BC) detection compared to mammography, however, it is unknown whether this reduces interval cancer rate (ICR) at follow-up.
Methods: Using individual participant data (IPD) from DBT screening studies (identified via periodic literature searches July 2016 to November 2019) we performed an IPD meta-analysis. We estimated ICR for DBT-screened participants and the difference in pooled ICR for DBT and mammography-only screening, and compared interval BC characteristics. Two-stage meta-analysis (study-specific estimation, pooled synthesis) of ICR included random-effects, adjusting for study and age, and was estimated in age and density subgroups. Comparative screening sensitivity was calculated using screen-detected and interval BC data.
Findings: Four prospective DBT studies, from European population-based programs, contributed IPD for 66,451 DBT-screened participants: age-adjusted pooled ICR was 13.17/10,000 (95%CI: 8.25-21.02). Pooled ICR was higher in the high-density (21.08/10,000; 95%CI: 6.71-66.27) than the low-density (8.63/10,000; 95%CI: 5.25-14.192) groups (P = 0.03) however estimates did not differ across age-groups (P = 0.32). Based on two studies that also provided data for 153,800 mammography screens (age-adjusted ICR 17.69/10,000; 95%CI: 13.22-23.66), DBT's pooled ICR was 16.83/10,000 (95%CI: 11.89-23.82). Comparative meta-analysis showed a non-significant difference in ICR (-0.44/10,000; 95%CI: -11.00-10.11) and non-significant difference in screening sensitivity (6.79%; 95%CI: -0.73-14.87%) between DBT and DM but a significant pooled difference in cancer detection rate of 33.49/10,000 (95%CI: 23.88-43.10). Distribution of interval BC prognostic characteristics did not differ between screening modalities except that those occurring in DBT-screened participants were significantly more likely to be negative for axillary-node metastases (P = 0.005).
Interpretation: Although heterogeneity in ICR estimates and few datasets limit recommendations, there was no difference between DBT and mammography in pooled ICR despite DBT increasing cancer detection. (C) 2021 The Author(s). Published by Elsevier Ltd
From the Yellow Springs to the Land of Immortality
The Yellow Springs is a vivid metaphorical reference to the final destination of a mortal being and the dwelling place of a departed one in ancient China. In the writings of philosophers, historians, and poets during the long period of Chinese history, the Yellow Springs is not only considered as an underground physical locus where a grave is situated, but also an emotionally charged space invoke grieving, longing, and memory for the departed loved ones. The subterranean dwelling at the Yellow Springs is both a destination for a departed mortal being and an intermediary place to an ideal and imaginative realm, the land of immortality where the soul would enjoy eternity. From the Yellow Springs to the Land of Immortality is an exhibition that highlights sixteen carefully selected artworks from Gettysburg College’s Special Collections; each object embodies the perceptions and ritual practices of the rich funerary culture in the historical period in China, ranging from the late second millennium BCE to the beginning of the early twentieth century. These artifacts represent various artistic traditions and fabrication techniques — including jade carving, bronze casting, glazed pottery making — and most importantly, offer a glimpse of how art and artifacts are employed as a means to connect the living with the soul of the departed one in the Yellow Springs. Archaeo- logical discoveries in the past four decades in China have provided rich information that helps contextualize the sixteen artworks, as well as intimate knowledge about how the objects might “perform” in the life and afterlife of the individuals in the past.
The practice of burying goods alongside departed loved ones has had a long tradition in China. The artworks included in this exhibition catalogue, encompassing the major dynasties in Chinese history, epitomize such a practice from a historical point of view. The bronze jue of the Shang dynasty (mid-16th c.-1046 BCE), and the miniature bell, a replica of yong bronze bell of the Zhou dynasty (1045-256 BCE), are not only ceremonial paraphernalia used by elites in ancestral sacrifices during the Bronze Age, but also material manifestations of ritual and music, the very foundations of ancient Chinese civilization. Comparable examples found in Bronze Age tombs illustrate the idea to connect the deceased, often the owner of these ritual objects, to the ancestors in the netherworld as they themselves were transitioned into the role of ancestors through a series of funerary ceremonies. [excerpt]https://cupola.gettysburg.edu/artcatalogs/1034/thumbnail.jp
Protemic identification of Germline Proteins in Caenorhabditis elegans
Sexual reproduction involves fusion of 2 haploid gametes to form diploid offspring with genetic contributions from both parents. Gamete formation represents a unique developmental program involving the action of numerous germline-specific proteins. In an attempt to identify novel proteins involved in reproduction and embryonic development, we have carried out a proteomic characterization of the process in Caenorhabditis elegans. To identify candidate proteins, we used 2D gel electrophoresis (2DGE) to compare protein abundance in nucleus-enriched extracts from wild-type C. elegans, and in extracts from mutant worms with greatly reduced gonads (glp-4(bn2) worms reared at 25°C); 84 proteins whose abundance correlated with germline presence were identified. To validate candidates, we used feeding RNAi to deplete candidate proteins, and looked for reduction in fertility and/or germline cytological defects. Of 20 candidates so screened for involvement in fertility, depletion of 13 (65%) caused a significant reduction in fertility, and 6 (30%) resulted in sterility (\u3c5 % of wild-type fertility). Five of the 13 proteins with demonstrated roles in fertility have not previously been implicated in germline function. The high frequency of defects observed after RNAi depletion of candidate proteins suggests that this approach is effective at identifying germline proteins, thus contributing to our understanding of this complex organ
A multi-stage genome-wide association study of bladder cancer identifies multiple susceptibility loci.
We conducted a multi-stage, genome-wide association study of bladder cancer with a primary scan of 591,637 SNPs in 3,532 affected individuals (cases) and 5,120 controls of European descent from five studies followed by a replication strategy, which included 8,382 cases and 48,275 controls from 16 studies. In a combined analysis, we identified three new regions associated with bladder cancer on chromosomes 22q13.1, 19q12 and 2q37.1: rs1014971, (P = 8 × 10⁻¹²) maps to a non-genic region of chromosome 22q13.1, rs8102137 (P = 2 × 10⁻¹¹) on 19q12 maps to CCNE1 and rs11892031 (P = 1 × 10⁻⁷) maps to the UGT1A cluster on 2q37.1. We confirmed four previously identified genome-wide associations on chromosomes 3q28, 4p16.3, 8q24.21 and 8q24.3, validated previous candidate associations for the GSTM1 deletion (P = 4 × 10⁻¹¹) and a tag SNP for NAT2 acetylation status (P = 4 × 10⁻¹¹), and found interactions with smoking in both regions. Our findings on common variants associated with bladder cancer risk should provide new insights into the mechanisms of carcinogenesis
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