2,576 research outputs found
A Syntactical Analysis of Lewis’s Triviality Result
The first part of the paper contains a probabilistic axiomatic extension of the conditional system WV, here named WVPr. This system is extended with the axiom (Pr4): PrA = 1 ⊃ □A. The resulting system, named WVPr∗, is proved to be consistent and non-trivial, in the sense that it does not contain the wff (Triv): A ≡□A. Extending WVPr∗ with the so-called Generalized Stalnaker’s Thesis (GST) yields the (first) Lewis’s Triviality Result (LTriv) in the form (◊(A ∧ B) ∧◊(A ∧ ¬B)) ⊃ PrB|A = PrB. In §4 it is shown that a consequence of this theorem is the thesis (CT1): ¬A ⊃ (A > B ⊃ A ⥽ B). It is then proven that (CT1) subjoined to the conditional system WVPr∗ yields the collapse formula (Triv). The final result is that WVPr∗+(GST) is equivalent to WVPr∗+(Triv). In the last section a discussion is opened about the intuitive and philosophical plausibility of axiom (Pr4) and its role in the derivation of (Triv)
Explicit Conditionals in the Framework of Classical Conditional Logic
The paper proposes a first approach to systems whose language includes two primitives (>+ and >-) as symbols for factual and counterfactual conditionals which are explicit, i.e. that are stated jointly with the truth or falsity of the antecedent clause. In systems based on this language, here called 2-conditional, the standard corner operator may be defined by (Def>) A > B := (A >+ B)∨(A >- B), while in classical conditional systems one could introduce the two symbols for explicit conditionals by the definitions (Def>+) A >+ B := A∧(A>B) and (Def>-) A>- B := ¬A∧(A>B). Two 2-conditional systems, V² and VW², are axiomatized and proved to be definitionally equivalent to the monoconditional systems V and VW. A third system VWTr² is characterized by an axiom stating the transitivity of factual conditionals and is shown to be distinct from V², from VW² and from the 2-conditional version of Lewis’ well-known system VC, here named VC². The same may be said for a fourth system VW²◊ ±, based on an axiom inderivable in VC²: ◊(A >+ B) ⊃ ◊( ¬A >- ¬B). VC² contains what is here called a “semi-collapse” of the operator >+ and it is argued that it is inadequate as a logic for both factual and counterfactual conditionals. The last section shows that several different definitions of the corner operators in terms of >+ and >- may be introduced as an alternative to (Def>)
Competing during a pandemic? Retailers’ ups and downs during the COVID-19 outbreak
The COVID-19 pandemic (that started in early 2020) is causing several disruptions in the short- and mid-term, to which businesses have to adapt. Some retailers have reacted to the emergency immediately, displaying a plethora of different intervention types. The authors aim to synthesize the challenges that retailers are facing during the COVID-19 emergency. We do this from the perspective of both consumers and managers, with the goal of providing guidelines on and examples of how retailers can handle this unprecedented situation
Tweets to escape: intercultural differences in consumer expectations and risk behavior during the COVID-19 lockdown in three European countries
This study aims to understand the extent to which a time of emergency, (e.g. the COVID-19 pandemic), impacts consumer behaviour in terms of risk and expectations. The methodology involves the systematic content analysis of 15,000 tweets collected from three countries (UK, Italy and Spain) in April 2020. The results suggest that the top-of-mind expectation by consumers deals with escaping from home and enjoying freedom, either by having a good meal (UK), drinking alcoholic beverages (Spain), or travelling (Italy). They also suggest that the high levels of risk individuals were exposed to during the pandemic will not influence behavior in the long-term post- lockdown. Instead, they suggest consumers are willing to restore their consumption levels especially of activities that contribute to the sense of escapism. Finally, results provide evidence of the cultural differences emerging from consumers from different countries during the pandemic. Implications for international marketers and retailers are provided
MODULATORY ROLE OF MONOMERIC AMYLOID BETA ON NEURONAL EXCITABILITY AND ITS IMPLICATIONS ON SYNAPTIC ACTIVITY OF IMMATURE CORTICAL NEURONS
So far the amyloid hypothesis has mainly driven the Alzheimer's Disease (AD) drugs development; however most of the anti A\u3b2-clinical trials have been suspended due to the lack of significant cognitive improvements as well as to the side effects caused in AD patients in some studies. Although the negative outcomes of \u3b2- and \u3b3-secretases targeting therapies are reasonable explained by the significant biological functions covered by such proteases, the reason A\u3b2-centric therapies fail is still unclear. Thus, to design a successful therapy for AD it is therefore crucial to uncover the role of soluble endogenous A\u3b2 in the healthy brain. Even though the amyloid peptide has been extensively studied because of its association to AD, its physiological function(s) is now being studied in much more detail. My thesis work is part of the recently emerging idea that A\u3b2 \u2013 at low concentrations - is not just a toxic waste product of the brain but it might be a relevant element involved in the maintenance of neuronal network homeostasis. Our final goal is therefore to explore the effects of the monomeric A\u3b21-42 peptide on excitable cells
Protein kinase CK2 is widely expressed in follicular, Burkitt and diffuse large B-cell lymphomas and propels malignant B-cell growth.
Serine-threonine kinase CK2 is highly expressed and pivotal for survival and proliferation in multiple myeloma, chronic lymphocytic leukemia and mantle cell lymphoma. Here, we investigated the expression of \u3b1 catalytic and \u3b2 regulatory CK2 subunits by immunohistochemistry in 57 follicular (FL), 18 Burkitt (BL), 52 diffuse large B-cell (DLBCL) non-Hodgkin lymphomas (NHL) and in normal reactive follicles. In silico evaluation of available Gene Expression Profile (GEP) data sets from patients and Western blot (WB) analysis in NHL cell-lines were also performed. Moreover, the novel, clinical-grade, ATP-competitive CK2-inhibitor CX-4945 (Silmitasertib) was assayed on lymphoma cells. CK2 was detected in 98.4% of cases with a trend towards a stronger CK2\u3b1 immunostain in BL compared to FL and DLBCL. No significant differences were observed between Germinal Center B (GCB) and non-GCB DLBCL types. GEP data and WB confirmed elevated CK2 mRNA and protein levels as well as active phosphorylation of specific targets in NHL cells. CX-4945 caused a dose-dependent growth-arresting effect on GCB, non-GCB DLBCL and BL cell-lines and it efficiently shut off phosphorylation of NF-\u3baB RelA and CDC37 on CK2 target sites. Thus, CK2 is highly expressed and could represent a suitable therapeutic target in BL, FL and DLBCL NHL
Non-adherence to eye care in people with diabetes
Objective Evaluate individual factors that impact adherence to eye care follow-up in patients with diabetes. Design and methods A 4-year retrospective chart review was conducted for 1968 patients with diabetes over age 40 from an urban academic center. Data collected included demographics, insurance, visual acuity, smoking status, medications, dates of dilated fundus examinations (DFE), and reported hemoglobin A1C and blood glucose levels. The primary outcome was timely DFE follow-up adherence following the initial eye exam visit. Results Overall, 41.6% of patients adhered to initial follow-up eye care recommendations. Multivariable analysis demonstrated that patients with severe diabetic retinopathy (DR) were more adherent than patients with mild DR (OR 1.86). Other variables associated with increased adherence were visual impairment and reported A1C or blood glucose. Smoking was associated with decreased adherence. Ethnicity and insurance were also significantly associated with adherence. Longitudinal follow-up rates were influenced by additional factors, including ethnicity and neighborhood deprivation index. Conclusions Patients with moderate to severe DR and/ or visual impairment were more likely to adhere to timely DFE follow-up. This could relate to the presence of visual symptoms and/or other systemic manifestations of diabetes. Smokers were less likely to adhere to timely DFE follow-up. One hypothesis is patients who smoke have other symptomatic health problems which patients prioritize over asymptomatic ocular disorders. In order to reduce vision loss from DR, practitioners should be aware that patients with mild and moderate DR, patients with normal vision, and smokers are at greater risk for poor follow-up eye care adherence. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved
Investigating genetic and phenotypic variability of queen bees: Morphological and reproductive traits
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