202 research outputs found
Tests of Concepts in Herbert Blumer's Method
Herbert Blumer left tlnclear the bearing of his method on substantive arguments thathemade about socialunrest, socialproblems, public opinion, race relations, andmass society. These argllments cOllldscarcelY have been grounded upon that weI/-known fundamental of his method, direct observation of ongoing social interaction. Th~ are, boneoer, consistent with another centralprinciple discussed in Blumer's essay on method empirical tests of concepts. Several of hisarticles onsubstantive concepts suggest thekindsof results that may bepursued with concept testing
Yesterday\u27s People: Life in Contemporary Appalachia
The distinctive way of life of the Southern Appalachian people has often been criticized, romanticized or derided, but rarely has it been understood. Yesterday’s People, the fruit of many years’ labor in the mountains, reveals the fears, anxieties, and hopes that underlie the mountaineers’ way of thinking and acting, and thereby shape their relationships in family and community. First published in 1965, this book has been an indispensable guide for all who seek to study, work or live within the Appalachian culture.
Mr. Weller presents, with compassion and humor, one of the most incisive studies that has been made of an American folk community. It contains many quotable passages about social classes in America, and about Appalachia in particular. -- Publishers Weeklyhttps://uknowledge.uky.edu/upk_appalachian_studies/1030/thumbnail.jp
Complement Receptor Type 1 (CR1, CD35) Is a Receptor for C1q
AbstractMolecular definition of the cellular receptor for the collagen domain of C1q has been elusive. We now report that C1q binds specifically to human CR1 (CD35), the leukocyte C3b/C4b receptor, and the receptor on erythrocytes for opsonized immune complexes. Biotinylated or radioiodinated C1q (*C1q) bound specifically to transfected K562 cells expressing cell surface CR1 and to immobilized recombinant soluble CR1 (rsCR1). *C1q binding to rsCR1 was completely inhibited by unlabeled C1q and the collagen domain of C1q and was partially inhibited by C3b dimers. Kinetic analysis in physiologic saline of the interaction of unlabeled C1q with immobilized rsCR1 using surface plasmon resonance yielded an apparent equilibrium dissociation constant (Keq2) of 3.9 nM. Thus, CR1 is a cellular C1q receptor that recognizes all three complement opsonins, namely, C1q, C3b, and C4b
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Barriers to early diagnosis of symptomatic breast cancer: a qualitative study of Black African, Black Caribbean and White British women living in the UK
Objectives:
Understanding barriers to early diagnosis of symptomatic breast cancer among Black African, Black Caribbean and White British women in the UK.
Design:
In-depth qualitative interviews using grounded theory methods to identify themes. Findings validated through focus groups.
Participants:
94 women aged 33–91 years; 20 Black African, 20 Black Caribbean and 20 White British women diagnosed with symptomatic breast cancer were interviewed. Fourteen Black African and 20 Black Caribbean women with (n=19) and without (n=15) breast cancer participated in six focus groups.
Setting:
Eight cancer centres/hospital trusts in London (n=5), Somerset (n=1), West Midlands (n=1) and Greater Manchester (n=1) during 2012–2013.
Results:
There are important differences and similarities in barriers to early diagnosis of breast cancer between Black African, Black Caribbean and White British women in the UK. Differences were influenced by country of birth, time spent in UK and age. First generation Black African women experienced most barriers and longest delays. Second generation Black Caribbean and White British women were similar and experienced fewest barriers. Absence of pain was a barrier for Black African and Black Caribbean women. Older White British women (≥70 years) and first generation Black African and Black Caribbean women shared conservative attitudes and taboos about breast awareness. All women viewed themselves at low risk of the disease, and voiced uncertainty over breast awareness and appraising non-lump symptoms. Focus group findings validated and expanded themes identified in interviews.
Conclusions:
Findings challenged reporting of Black women homogenously in breast cancer research. This can mask distinctions within and between ethnic groups. Current media and health promotion messages need reframing to promote early presentation with breast symptoms. Working with communities and developing culturally appropriate materials may lessen taboos and stigma, raise awareness, increase discussion of breast cancer and promote prompt help-seeking for breast symptoms among women with low cancer awareness
From block-Toeplitz matrices to differential equations on graphs: towards a general theory for scalable masked Transformers
In this paper we provide, to the best of our knowledge, the first
comprehensive approach for incorporating various masking mechanisms into
Transformers architectures in a scalable way. We show that recent results on
linear causal attention (Choromanski et al., 2021) and log-linear RPE-attention
(Luo et al., 2021) are special cases of this general mechanism. However by
casting the problem as a topological (graph-based) modulation of unmasked
attention, we obtain several results unknown before, including efficient
d-dimensional RPE-masking and graph-kernel masking. We leverage many
mathematical techniques ranging from spectral analysis through dynamic
programming and random walks to new algorithms for solving Markov processes on
graphs. We provide a corresponding empirical evaluation.Comment: 20 pages, 12 figure
Catalysis of Strand Exchange by the HSV-1 UL12 and ICP8 Proteins: Potent ICP8 Recombinase Activity is Revealed upon Resection of dsDNA Substrate by Nuclease
The replication of herpes simplex virus type 1 (HSV-1) is associated with a high degree of homologous recombination, which is likely to be mediated, in part, by HSV-1-encoded proteins. We have previously shown that the HSV-1 encoded ICP8 protein and alkaline nuclease UL12 are capable of catalyzing an in vitro strand-exchange reaction. Here, we show, by electron microscopy, that the products of the strand exchange reaction between linear double-stranded DNA and circular single-stranded DNA consist of the expected joint molecule forms: sigma, alpha, and gapped circles. Other exonucleases, such as lambda Red α, which, like UL12, digests 5′-3′, as well as Escherichia coli exonuclease III (ExoIII), which digests 3′-5′, could substitute for UL12 in the strand exchange reaction by providing a resected DNA end. ICP8 generated the same intermediates and strand exchange products when the double-stranded DNA substrate was preresected by any of the nucleases. Using substrates with large regions of non-homology we found that pairing by ICP8 could be initiated from the middle of a DNA molecule and did not require a homologous end. In this reaction, the resection of a DNA end by the nuclease is required to reveal homologous sequences capable of being paired by ICP8. This study further illustrates the complexity of the multi-functional ICP8 protein
Evolution of AANAT: expansion of the gene family in the cephalochordate amphioxus
<p>Abstract</p> <p>Background</p> <p>The arylalkylamine <it>N</it>-acetyltransferase (AANAT) family is divided into structurally distinct vertebrate and non-vertebrate groups. Expression of vertebrate AANATs is limited primarily to the pineal gland and retina, where it plays a role in controlling the circadian rhythm in melatonin synthesis. Based on the role melatonin plays in biological timing, AANAT has been given the moniker "the Timezyme". Non-vertebrate AANATs, which occur in fungi and protists, are thought to play a role in detoxification and are not known to be associated with a specific tissue.</p> <p>Results</p> <p>We have found that the amphioxus genome contains seven <it>AANAT</it>s, all having non-vertebrate type features. This and the absence of <it>AANATs </it>from the genomes of Hemichordates and Urochordates support the view that a major transition in the evolution of the <it>AANATs </it>may have occurred at the onset of vertebrate evolution. Analysis of the expression pattern of the two most structurally divergent <it>AANAT</it>s in <it>Branchiostoma lanceolatum </it>(<it>bl</it>) revealed that they are expressed early in development and also in the adult at low levels throughout the body, possibly associated with the neural tube. Expression is clearly not exclusively associated with the proposed analogs of the pineal gland and retina. blAANAT activity is influenced by environmental lighting, but light/dark differences do not persist under constant light or constant dark conditions, indicating they are not circadian in nature. bfAANATα and bfAANATδ' have unusually alkaline (> 9.0) optimal pH, more than two pH units higher than that of vertebrate AANATs.</p> <p>Conclusions</p> <p>The substrate selectivity profiles of bfAANATα and δ' are relatively broad, including alkylamines, arylalkylamines and diamines, in contrast to vertebrate forms, which selectively acetylate serotonin and other arylalkylamines. Based on these features, it appears that amphioxus AANATs could play several roles, including detoxification and biogenic amine inactivation. The presence of seven AANATs in amphioxus genome supports the view that arylalkylamine and polyamine acetylation is important to the biology of this organism and that these genes evolved in response to specific pressures related to requirements for amine acetylation.</p
Starlit: Privacy-Preserving Federated Learning to Enhance Financial Fraud Detection
Federated Learning (FL) is a data-minimization approach enabling collaborative model training across diverse clients with local data, avoiding direct data exchange. However, state-of-the-art FL solutions to identify fraudulent financial transactions exhibit a subset of the following limitations. They (1) lack a formal security definition and proof, (2) assume prior freezing of suspicious customers’ accounts by financial institutions (limiting the solutions’ adoption), (3) scale poorly, involving either computationally expensive modular exponentiation (where is the total number of financial institutions) or highly inefficient fully homomorphic encryption, (4) assume the parties have already completed the identity alignment phase, hence excluding it from the implementation, performance evaluation, and security analysis, and (5) struggle to resist clients’ dropouts. This work introduces Starlit, a novel scalable privacy-preserving FL mechanism that overcomes these limitations. It has various applications, such as enhancing financial fraud detection, mitigating terrorism, and enhancing digital health. We implemented Starlit and conducted a thorough performance analysis using synthetic data from a key player in global financial transactions. The evaluation indicates Starlit’s scalability, efficiency, and accuracy
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