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Real-time decoding of question-and-answer speech dialogue using human cortical activity.
Natural communication often occurs in dialogue, differentially engaging auditory and sensorimotor brain regions during listening and speaking. However, previous attempts to decode speech directly from the human brain typically consider listening or speaking tasks in isolation. Here, human participants listened to questions and responded aloud with answers while we used high-density electrocorticography (ECoG) recordings to detect when they heard or said an utterance and to then decode the utterance's identity. Because certain answers were only plausible responses to certain questions, we could dynamically update the prior probabilities of each answer using the decoded question likelihoods as context. We decode produced and perceived utterances with accuracy rates as high as 61% and 76%, respectively (chance is 7% and 20%). Contextual integration of decoded question likelihoods significantly improves answer decoding. These results demonstrate real-time decoding of speech in an interactive, conversational setting, which has important implications for patients who are unable to communicate
Transforming carbon nanotubes by silylation: An ab initio study
We use ab initio density functional calculations to study the chemical
functionalization of single-wall carbon nanotubes and graphene monolayers by
silyl (SiH3) radicals and hydrogen. We find that silyl radicals form strong
covalent bonds with graphene and nanotube walls, causing local structural
relaxations that enhance the sp3 character of these graphitic nanostructures.
Silylation transforms all carbon nanotubes into semiconductors, independent of
their chirality. Calculated vibrational spectra suggest that specific frequency
shifts can be used as a signature of successful silylation.Comment: 4 pages, 3 figure
Current and future approaches in the prevention and treatment of diabetic retinopathy
Diabetic retinopathy (DR) is a major cause of blindness worldwide and is the number one cause of blindness in working-age individuals in developed countries. We review the current literature and discuss the pathogenesis, modifying risk factors, genetics, and treatment of DR. Special focus is placed on the rationale and effectiveness of therapeutic modalities, both current and future
Trends and Variation in End-of-Life Care for Medicare Beneficiaries With Severe Chronic Illness
Provides an updated analysis of regional and hospital variations in end-of-life care for Medicare beneficiaries with chronic illnesses, including percentage of hospital deaths, days in intensive care units, and physician labor per patient
Gravitational Lensing by Power-Law Mass Distributions: A Fast and Exact Series Approach
We present an analytical formulation of gravitational lensing using familiar
triaxial power-law mass distributions, where the 3-dimensional mass density is
given by . The deflection angle and magnification factor are
obtained analytically as Fourier series. We give the exact expressions for the
deflection angle and magnification factor. The formulae for the deflection
angle and magnification factor given in this paper will be useful for numerical
studies of observed lens systems. An application of our results to the Einstein
Cross can be found in Chae, Turnshek, & Khersonsky (1998). Our series approach
can be viewed as a user-friendly and efficient method to calculate lensing
properties that is better than the more conventional approaches, e.g.,
numerical integrations, multipole expansions.Comment: 24 pages, 3 Postscript figures, ApJ in press (October 10th
Speak, Memory: An Archaeology of Books Known to ChatGPT/GPT-4
In this work, we carry out a data archaeology to infer books that are known
to ChatGPT and GPT-4 using a name cloze membership inference query. We find
that OpenAI models have memorized a wide collection of copyrighted materials,
and that the degree of memorization is tied to the frequency with which
passages of those books appear on the web. The ability of these models to
memorize an unknown set of books complicates assessments of measurement
validity for cultural analytics by contaminating test data; we show that models
perform much better on memorized books than on non-memorized books for
downstream tasks. We argue that this supports a case for open models whose
training data is known.Comment: EMNLP 2023 camera-ready (16 pages, 4 figures
Attention-deficit/hyperactivity disorder medication and seizures
OBJECTIVE:
Individuals with attention-deficit/hyperactivity disorder (ADHD) are at increased risk of seizures, but there is uncertainty about whether ADHD medication treatment increases risk among patients with and without preexisting seizures.
METHODS:
We followed a sample of 801,838 patients with ADHD who had prescribed drug claims from the Truven Health MarketScan Commercial Claims and Encounters databases to examine whether ADHD medication increases the likelihood of seizures among ADHD patients with and without a history of seizures. First, we assessed overall risk of seizures among patients with ADHD. Second, within-individual concurrent analyses assessed odds of seizure events during months when a patient with ADHD received ADHD medication compared with when the same individual did not, while adjusting for antiepileptic medications. Third, within-individual long-term analyses examined odds of seizure events in relation to the duration of months over the previous 2 years patients received medication.
RESULTS:
Patients with ADHD were at higher odds for any seizure compared with non-ADHD controls (odds ratio [OR] = 2.33, 95% confidence interval [CI] = 2.24-2.42 males; OR = 2.31, 95% CI = 2.22-2.42 females). In adjusted within-individual comparisons, ADHD medication was associated with lower odds of seizures among patients with (OR = 0.71, 95% CI = 0.60-0.85) and without (OR = 0.71, 95% CI = 0.62-0.82) prior seizures. Long-term within-individual comparisons suggested no evidence of an association between medication use and seizures among individuals with (OR = 0.87, 95% CI = 0.59-1.30) and without (OR = 1.01, 95% CI = 0.80-1.28) a seizure history.
CONCLUSIONS:
Results reaffirm that patients with ADHD are at higher risk of seizures. However, ADHD medication was associated with lower risk of seizures within individuals while they were dispensed medication, which is not consistent with the hypothesis that ADHD medication increases risk of seizures
Assessment of the genetic basis of rosacea by genome-wide association study.
Rosacea is a common, chronic skin disease that is currently incurable. Although environmental factors influence rosacea, the genetic basis of rosacea is not established. In this genome-wide association study, a discovery group of 22,952 individuals (2,618 rosacea cases and 20,334 controls) was analyzed, leading to identification of two significant single-nucleotide polymorphisms (SNPs) associated with rosacea, one of which replicated in a new group of 29,481 individuals (3,205 rosacea cases and 26,262 controls). The confirmed SNP, rs763035 (P=8.0 × 10(-11) discovery group; P=0.00031 replication group), is intergenic between HLA-DRA and BTNL2. Exploratory immunohistochemical analysis of HLA-DRA and BTNL2 expression in papulopustular rosacea lesions from six individuals, including one with the rs763035 variant, revealed staining in the perifollicular inflammatory infiltrate of rosacea for both proteins. In addition, three HLA alleles, all MHC class II proteins, were significantly associated with rosacea in the discovery group and confirmed in the replication group: HLA-DRB1*03:01 (P=1.0 × 10(-8) discovery group; P=4.4 × 10(-6) replication group), HLA-DQB1*02:01 (P=1.3 × 10(-8) discovery group; P=7.2 × 10(-6) replication group), and HLA-DQA1*05:01 (P=1.4 × 10(-8) discovery group; P=7.6 × 10(-6) replication group). Collectively, the gene variants identified in this study support the concept of a genetic component for rosacea, and provide candidate targets for future studies to better understand and treat rosacea
The Relationship between CD27 Negative and Positive B Cell Populations in Human Peripheral Blood
CD27 expression has been used to distinguish between memory and naive B cells in humans. However, low levels of mutated and isotype-switched CD27−IgD− cells are seen in healthy adults, and these are increased in some autoimmune diseases and in the elderly. Thus CD27 is not a universal marker of memory B cells in humans. Various hypotheses have been put forward as to the function of the CD27− memory population. Since we have previously found high-throughput IGHV repertoire analysis useful to distinguish “innate-like” memory B cells (CD27+IgD+), we have employed similar analyses to elucidate the relationship between CD27− and CD27+ memory B cells. IgM+IgD− memory cells in both the CD27+ and CD27− compartments share the unique characteristics of the “innate-like” IgM+IgD+CD27+ cells. The switched CD27+ and CD27− memory cells share a similar IGHV repertoire, having more in common with each other than with “innate-like” memory cells, although it is interesting that IgG2 and IgA2 subclasses of antibody in both switched memory populations have a more “innate-like” repertoire. Clonality analysis shows evidence of a close clonal relationship between the two populations in that both CD27− and CD27+ switched memory cells can be found in the same genealogical tree. The expression of CD27 does not appear to occur in a linear developmental fashion, since we see CD27− cells as precursors of CD27+ cells and vice versa. Despite the similarities, the CDR-H3 repertoire of the CD27− cells is significantly different from both the CD27+IgD+ and CD27+IgD− populations, indicating that perhaps the lack of CD27 might be related to binding properties of the Ig CDR-H3 region
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