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61.
We present a general classification of the conditions under which cognitive science, concerned, e.g. with decision making, requires the use of quantum theoretical notions. The analysis is done in the frame of the mathematical approach based on the theory of quantum measurements. We stress that quantum effects in cognition can arise only when decisions are made under uncertainty. Conditions for the appearance of quantum interference in cognitive sciences and the conditions when interference cannot arise are formulated. 相似文献
62.
Suk Ho Sohn Kyung Hwan Kim Yeiwon Lee Jae Woong Choi Ho Young Hwang 《The Journal of thoracic and cardiovascular surgery》2021,161(5):1788-1798.e5
ObjectiveThis study was conducted to compare the outcomes of rigid ring versus De Vega annuloplasty for the treatment of functional tricuspid regurgitation (TR).MethodsFrom 2003 to 2017, De Vega annuloplasty (group D) was used in 231 patients, and rigid ring annuloplasty (group R) was used in 204 patients for the treatment of functional TR during left-sided valve surgery. A propensity score-matching analysis was used to pair group D (n = 109) with group R (n = 109). The primary outcomes were long-term overall survival and cardiac death, and the secondary outcomes were tricuspid valve-related events and TR recurrence (TR moderate or severe). The follow-up data were complete in 99.6% (447 out of 449) of the patients with a follow-up duration of 102 months.ResultsThere were no differences in the overall survival and cardiac death between the propensity score-matched groups (P = .793 and P = .175, respectively) up to 14 years after surgery. Tricuspid valve-related events, including cardiac death, permanent pacemaker implantation, thromboembolism, bleeding and tricuspid valve reoperation were also similar between the 2 matched groups during the follow-up (P > .999). However, cumulative incidence of TR recurrence was significantly higher in group R than in group D (P = .007). Multivariate analysis indicated the annuloplasty method (De Vega) and preoperative TR grade as risk factors for late TR recurrence.ConclusionsIn functional TR, annuloplasty methods did not influence long-term overall survival, cardiac mortality, and tricuspid valve-related events. However, rigid ring annuloplasty showed less late TR recurrence. Rigid ring annuloplasty can be considered for the treatment of functional TR in terms of its better durability. 相似文献
63.
64.
M. CHITLUR B. SORENSEN G. E. RIVARD G. YOUNG J. INGERSLEV M. OTHMAN D. NUGENT G. KENET M. ESCOBAR J. LUSHER 《Haemophilia》2011,17(3):532-537
Summary. Laboratory evaluation of bleeding disorders has been performed with the standard clotting assays such as the PT and PTT for several decades. Our improved understanding of the process of blood coagulation has now revealed the important role played by the cellular elements such as platelets, monocytes and red blood cells. The need for a test that can assess clotting in a more ‘global’ manner, beyond the initiation of clot formation, has led to greater interest in assays such as thrombin generation and thromboelastography. Even though there are several publications using thromboelastography it remains a research tool as the methodology is not standardized. In an attempt to show reproducibility and consistency using thromboelastography, a group of investigators from different countries joined hands to form the TEG‐ROTEM Working Group. Two studies were performed using PRP and FVIII deficient plasma and an intrinsic pathway activator. This article summarizes the results of the first international effort at standardization of thromboelastography. Both of the instruments using this technology (TEG® and ROTEM®) were used. Nine laboratories from countries around the globe participated in this effort. The results showed a significant inter‐laboratory variance with CV’s greater than 10%. Although these results were not satisfactory, this has been the first effort to standardize this methodology and significant work remains to be done to improve reliability and reproducibility. These studies were performed on PRP and the results may be more reliable when preformed on whole blood samples. We believe that it is important to continue this work so that we may investigate the usefulness and potential applications of thromboelastography in the evaluation of bleeding and thrombosis. 相似文献
65.
《Drug metabolism reviews》2012,44(1):235-248
66.
Memory exhibits episodic superposition, an analog of the quantum superposition of physical states: Before a cue for a presented or unpresented item is administered on a memory test, the item has the simultaneous potential to occupy all members of a mutually exclusive set of episodic states, though it occupies only one of those states after the cue is administered. This phenomenon can be modeled with a nonadditive probability model called overdistribution (OD), which implements fuzzy‐trace theory's distinction between verbatim and gist representations. We show that it can also be modeled based on quantum probability theory. A quantum episodic memory (QEM) model is developed, which is derived from quantum probability theory but also implements the process conceptions of global matching memory models. OD and QEM have different strengths, and the current challenge is to identify contrasting empirical predictions that can be used to pit them against each other. 相似文献
67.
Philip T. Ives 《International journal of radiation biology》2013,89(1):54-67
SummaryOregon-R males were tested in day-by-day sperm samples for dominant visible and hemizygous sex-linked mutations, fecundity (number of offspring produced), and crossing-over after exposure to cobalt-60 γ in the 100 r to 10 kr range. Tests totalled 42 184 X-chromosomes and 210 111 flies. Mutations were most frequent after irradiation during meiosis and spermiogenesis in low doses. Only sperm and gonial cells subsequently produced adult flies after exposure to 5 kr and 10 kr. After 500 r fecundity was reduced chiefly in cells in late mitosis, and in earlier and later stages with increasing doses. Reduced fecundity may not be due to the kind of mutation detected here, but both effects may combine to influence the frequency of mutations recovered, particularly from irradiated meiotic and spermiogenic cells. Males receiving 500 r might contribute more mutations to a population's gene pool than competing males after a substantially higher dose. 相似文献
68.
目的:腹腔镜胆囊切除术是治疗胆囊结石首选措施,早期治疗和护理干预可减轻患者的痛苦。本研究的目的在于比较紧急和延迟腹腔镜手术治疗急性胆囊炎的可行性及安全性,并对护理措施进行讨论。方法:将55例紧急腹腔镜胆囊切除术患者分为两组,A组为发病后72小时内紧急手术患者,B组为发病72小时后延迟手术患者。结果:A组中转为开腹手术19.4%,B组26.3%(P=0.693);平均手术时间(P=0.412)、总住院时间(P=0.626)、胆道损伤和手术后并发症,两组间差异比较无统计学意义。结论:紧急腹腔镜胆囊切除术安全,与延迟手术相比差异无统计学意义。 相似文献
69.
We compared monocular and binocular absolute thresholds of dark adaptation in two separate study populations. Eighteen healthy individuals (Group A) and 13 patients with chronic respiratory insufficiency (Group B) were examined three times each by computerised dark adaptometry with simultaneous but separate recordings from each eye and binocularly. The respiratory patients received oxygen supplement at visits 1 and 3. In Group A, at all three visits, binocular dark adaptation was significantly more sensitive (40.5%) than monocular dark adaptation with either eye. In Group B, at visits 1 and 3, binocular dark adaptation was also significantly more sensitive than monocular dark adaptation (40.5% higher than the right and 47% higher than the left eye). However, in Group B, at visit 2 without oxygen treatment, no significant differences were observed between monocular and binocular sensitivities. Binocular dark vision was superior to monocular dark vision in healthy individuals and in patients with respiratory insufficiency that were provided oxygen supplementation. Furthermore, deficit in oxygen seems to affect binocular summation, perhaps by impaired enhancement in the central nervous system. 相似文献
70.
The term “vagueness” describes a property of natural concepts, which normally have fuzzy boundaries, admit borderline cases, and are susceptible to Zeno's sorites paradox. We will discuss the psychology of vagueness, especially experiments investigating the judgment of borderline cases and contradictions. In the theoretical part, we will propose a probabilistic model that describes the quantitative characteristics of the experimental finding and extends Alxatib's and Pelletier's ( 2011 ) theoretical analysis. The model is based on a Hopfield network for predicting truth values. Powerful as this classical perspective is, we show that it falls short of providing an adequate coverage of the relevant empirical results. In the final part, we will argue that a substantial modification of the analysis put forward by Alxatib and Pelletier and its probabilistic pendant is needed. The proposed modification replaces the standard notion of probabilities by quantum probabilities. The crucial phenomenon of borderline contradictions can be explained then as a quantum interference phenomenon. 相似文献