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关键词： Breast neoplasms   Delayed diagnosis   Follow-up studies   Magnetic resonance imaging   Postoperative period  

摘要： Objectives To investigate outcomes and retrospectively evaluate characteristics of additional lesions initially assessed as BI-RADS category 3, 4, and 5 at preoperative MRI to determine appropriate follow-up management. Methods We retrospectively reviewed 429 lesions other than primary cancer initially assessed as BI-RADS category 3, 4, and 5 at preoperative MRI in 391 patients with breast cancer from March 2012 to December 2013. We investigated their malignancy rate and outcome according to BI-RADS category assessments. We also analyzed clinical and imaging characteristics of each lesion. Pathological results and imaging follow-up of at least 2 years were used as reference standards. Results Of 429 lesions in 391 patients (mean 48.1 years +/- 9.4), the malignancy rate of BI-RADS 3, 4, and 5 lesions was 1.4% (3/213), 17.8% (38/214), and 50% (1/2), respectively. Of BI-RADS 3 lesions or BI-RADS 4 or 5 lesions that were followed up after benign-concordant biopsy (n = 114), two contralateral masses (2/306, 0.7%) were diagnosed as malignancy at 13.3 and 33.2 months after initial detection, within a median follow-up of 63.3 months. None of the NME or foci or lesions followed up after benign-concordant biopsy had a delayed diagnosis of malignancy. Of the 391 patients, 97.4% (381/391) received at least one type of adjuvant therapy. Conclusion The incidence of delayed cancer diagnosis among additionally detected lesions other than primary cancer is very low and short-term follow-up is unnecessary. Contralateral masses which were not confirmed by biopsy may need annual follow-up.

关键词： Gradenigo's syndrome   Pediatrics   Petrous apicitis  

摘要： Gradenigo's Syndrome is a rare complication of otitis media and/or mastoiditis resulting in inflammation of the petrous apex of the temporal bone. Here, we highlight an interesting case from our institution, summarize available pediatric cases from the past fifty years to provide an updated diagnostic categorization for this rare condition with confusing nomenclature, and suggest guidance for diagnosis and management.

关键词： 14M15   18E30 (primary)  

摘要： We define and discuss some general properties of residual categories of Lefschetz decompositions in triangulated categories. In the case of the derived category of coherent sheaves on the Grassmannian G(k,n), we conjecture that the residual category associated with Fonarev's Lefschetz exceptional collection is generated by a completely orthogonal exceptional collection. We prove this conjecture for k=p, a prime number, modulo completeness of Fonarev's collection (and for p=3 we check this completeness).

关键词： Bladder   Cancer   Carcinomas   Grade   WHO   Nonmuscle-invasive   Urothelial  

摘要： Background: Papillary urothelial neoplasm of low malignant potential (PUN-LMP) was introduced as a noninvasive, noncancerous lesion and a separate grade category in 1998. Subsequently, PUN-LMP was reconfirmed by World Health Organization (WHO) 2004 and WHO 2016 classifications for urothelial bladder tumors. Objectives: To analyze the proportion of PUN-LMP diagnosis over time and to determine its prognostic value compared to Ta-LG (low-grade) and Ta-HG (high-grade) carcinomas. To assess the intraobserver variability of an experienced uropathologist assigning (WHO) 2004/2016 grades at 2 time points. Materials and methods: Individual patient data of 3,311 primary Ta bladder tumors from 17 hospitals in Europe and Canada were available. Transurethral resection of the tumor was performed between 1990 and 2018. Time to recurrence and progression were analyzed with cumulative incidence functions, log-rank tests and multivariable Cox-regression stratified by institution. Intraobserver variability was assessed by examining the same 314 transurethral resection of the tumorslides twice, in 2004 and again in 2018. Results: PUN-LMP represented 3.8% (127/3,311) of Ta tumors. The same pathologist found 71/314 (22.6%) PUN-LMPs in 2004 and only 20/314 (6.4%) in 2018. Overall, the proportion of PUN-LMP diagnosis substantially decreased over time from 31.3% (1990-2000) to 3.2% (2000-2010) and to 1.1% (2010-2018). We found no difference in time to recurrence between the three WHO 2004/2016 Ta-grade categories (log-rank, P = 0.381), nor for LG vs. PUN-LMP (log-rank, P = 0.238). Time to progression was different for all grade categories (log-rank, P < 0.001), but not between LG and PUN-LMP (log-rank, P = 0.096). Multivariable analyses on recurrence and progression showed similar results for all 3 grade categories and for LG vs. PUN-LMP. Conclusions: The proportion of PUN-LMP has decreased to very low levels in the last decade. Contrary to its reconfirmation in the WHO 2016 classification,

关键词： organizational theory   entrepreneurship   music industry   categories  

摘要： New entrants in established markets face competing recommendations over whether it is better to establish their legitimacy by conforming to type or to differentiate themselves from incumbents by proposing novel contributions. This dilemma is particularly acute in cultural markets in which demand for novelty and attention to legitimacy are both high. We draw upon research in organizational theory and entrepreneurship to hypothesize the effects of pursuing narrow or broad appeals on the performance of new entrants in the music industry. We propose that the sales of novel products vary with the distance perceived between the classes being combined and that this happens, in part, because combinations that appear to span great distances encourage consumers to adopt superordinate rather than subordinate classes (e.g., to classify and evaluate something as a "song" rather than a "country song"). Using a sample of 144 artists introduced to the public via the U.S. television program The Voice, we find evidence of a U-shaped relationship between category distance and consumer response. Specifically, consumers reward new entrants who pursue either familiarity (i.e., nonspanning) or distinctive combinations (i.e., combine distant genres) but reject efforts that try to balance both goals. An experimental test validates that manipulating the perceived distance an artist spans influences individual evaluations of product quality and the hierarchy of categorization. Together these results provide initial evidence that distant combinations are more likely to be classified using a superordinate category, mitigating the potential confusion and legitimacybased penalties that affect middle-distance combinations.

摘要： In the current imagining of sexuality, both within the academy and beyond it, the supposed fixity (and staidness) of identity categories such as lesbian, gay, and straight are often opposed to the putative lability (and transgressive thrill) of queerness. Queer is originally a distinctively American phenomenon (though the term was quickly taken up in other Anglophone societies);its emergence was provoked by and manifested in a host of coincident cultural and political developments in the United States of the late 1980s and early 1990s. Opposing the alleged assimilationism, gender-conformism, and whiteness of the so-called mainstream gay and lesbian movement, queer aligned itself with transgression, gender fluidity, and intersectionality. This paper tracks the deployment of queer in literary studies since 1990, concentrating on its vexed relation to the identity categories of lesbian and gay. If the founding gesture of queer theory is its rejection of identity, its equally foundational relation to same-sexuality has meant it is constantly forced into contortions-sometimes productive, sometimes not-with the identity categories through which same-sexuality has in the modern era largely been understood. I begin with an overview of the trajectory of queer as a critical term and the ways in which it has been deployed to imagine an anti-identitarian and antinormative politics. I then turn to discussions of sexual identity in recent literary studies. I suggest that if we are not quite seeing a "categorical turn" in recent queer literary criticism, the analytical and political value of identities has been undergoing galvanizing reassessment.

关键词： Pricing   Retailing   Game theory   Product substitution and complementarity   Information value  

摘要： This paper studies pricing strategies of competing retailers offering substitutable products in multiple product categories. For such retailers, in addition to accounting for within-category pricing effects, cross-category effects can also influence consumers' purchase decisions and thereby impact the retailers' optimal pricing strategies. We model consumers' utility for purchasing substitutable products from the same category and from other categories as well. We then solve a game-theoretic model to identify the retailers' optimal prices and profits. Our results show that accounting for cross-category effects largely influences the retailers' pricing and profitability. In particular, cross-category effects influence the sensitivity of prices to within-category substitution levels. While cross-category effects have an impact on retailers' equilibrium strategies, this effect is only relevant when within-category substitution effects are present. We also find that intentionally ignoring cross-category effects leads to lower prices for categories that are either substitutable or highly complementary, and to higher prices otherwise. When not accounting for the fact that the two categories are demand-related implies lower prices than when this information is accounted for, then at least one retailer chooses to disregard the cross-category effect at equilibrium. Finally, we find evidence for prisoner's dilemma situations where both retailers ignore cross-category effect at equilibrium while accounting for it would yield them higher profits.

关键词： Headache   Student   Africa   Factor analysis   McDonald's omega  

摘要： BackgroundPsychometric investigations of tools used in the screening of migraine including the migraine screen questionnaire (MS-Q), using an adequate statistical approach is needed. We assessed the psychometric properties of the migraine screen questionnaire (MS-Q) using categorical data *** and methodsA total of 343 students at Mizan-Tepi University, Ethiopia, age range=18-35years were selected by a simple random sampling method to participate in a cross-sectional study. The respondents completed the MS-Q, a semi-structured socio-demographic questionnaire, and a visual analog scale for attention (VAS-A).ResultsThe cumulative variance rule (>40%), the Kaiser's criteria (Eigenvalue>1), the Scree test and, the parallel analysis (minimum rank) identified a 1-factor model for the MS-Q with the factor loadings in the range of 0.78 to 0.84. Fit indices favored a 1-factor model of the MS-Q as indicated by comparative fit index (0.993), weighted root mean square residual (0.048), root mean square error of approximation (0.067), the goodness of fit index (1.00), and non-normed fit index (0.987). The values of the Factor Determinacy Index (0.953), marginal reliability (0.909), H-latent (0.909), H-observed (0.727), explained common variance (0.906) and the mean item residual absolute loadings (0.225) further complimented finding of the 1-Factor model. McDonald's Omega (0.903) suggested adequate internal consistency. Discriminative validity was supported by significantly higher scores for the total and all the MS-Q items except one among those with complaints of *** categorical methods support the psychometric validity of the MS-Q in the study population.

关键词： Distributional reinforcement learning   Estimated action value   Bootstrapping   Interval estimation  

摘要： Categorical Distributional Reinforcement Learning (CDRL) uses a categorical distribution with evenly spaced outcomes to model the entire distribution of returns and produces state-of-the-art empirical performance. However, using inappropriate bounds with CDRL may generate inaccurate estimated action values, which affect the policy update step and the final performance. In CDRL, the bounds of the distribution indicate the range of the action values that the agent can obtain in one task, without considering the policy's performance and state-action pairs. The action values that the agent obtains are often far from the bounds, and this reduces the accuracy of the estimated action values. This paper describes a method of obtaining more accurate estimated action values for CDRL using adaptive bounds. This approach enables the bounds of the distribution to be adjusted automatically based on the policy and state-action pairs. To achieve this, we save the weights of the critic network over a fixed number of time steps, and then apply a bootstrapping method. In this way, we can obtain confidence intervals for the upper and lower bound, and then use the upper and lower bound of these intervals as the new bounds of the distribution. The new bounds are more appropriate for the agent and provide a more accurate estimated action value. To further correct the estimated action values, a distributional target policy is proposed as a smoothing method. Experiments show that our method outperforms many state-of-the-art methods on the OpenAI gym tasks. (C) 2020 Elsevier B.V. All rights reserved.

关键词： word frequency   function words   content words   infants   lexical categorization   word order   acquisition of grammar   headturn preference   open-class/closed-class distinction  

摘要： The linguistic distinction between function words (functors) (e.g., the, he, that, on...), signaling grammatical structure, and content words (e.g., house, blue, carry...), carrying meaning, is universal across the languages of the world. These two lexical categories also differ in their phonological makeup (functors being shorter and more minimal) and frequency of occurrence (individual functors being much more frequent than most content words). The frequency-based discrimination of the two categories could constitute a powerful mechanism for infants to acquire the basic building blocks of language. As functors constitute closed classes and content words come in open classes, we examined whether 8-month-old monolingual infants relied on word frequency to categorize and track functors and content words. In six artificial grammar-learning experiments, we have found that infants process frequent words as belonging to closed classes, and infrequent words as belonging to open classes, and they map the relative order of these categories following the basic word order of their native language. These findings provide the earliest evidence that infants use word frequency as a cue to lexical categories and combine them to build rudimentary representations of grammar.