John Snow, the London doctor who studied cholera in the 1840s and 1850s, argued in Snow (1856) that water exerted an “overwhelming influence” on mortality in a region of south London during the 1854 ...outbreak. In a paper re-assessing Snow's analysis, Koch and Denike (2006) claim that “Snow made not merely minor arithmetic errors but more importantly critical, conceptual mistakes that adversely affected his results.” The claim of errors and mistakes is incorrect and due to a misreading or misunderstanding of Snow's data and analysis. Koch and Denike apply an inappropriate statistical test to Snow's original data (and do so incorrectly). More importantly, due to the misreading of the historical record they alter the underlying primary-source data, rendering their results invalid. Analysis of the data following Snow's approach but with modern statistical tools strongly supports Snow's claim for the primacy of water in accounting for variation in cholera mortality.
•Review a 2006 critique of John Snow's methodology in his 1856 analysis of south London.•Apply modern statistical techniques to re-examine John Snow's south London analysis.•Conclude that Snow's work did not suffer from the claimed methodological problems.•Support and confirm Snow's conclusion that water had an overwhelming effect on mortality.
Scientists often refer to spiritual experiences with science. This research addresses this unique component of science attitudes-
: feelings of meaning, awe, and connection derived through scientific ...ideas. Three studies (
= 1,197) examined individual differences in Spirituality of Science (SoS) and its benefits for well-being, meaning, and learning. Spirituality of Science was related to belief in science, but unlike other science attitudes, spirituality of science was also associated with trait awe and general spirituality (Study 1). spirituality of science also predicted meaning in life and emotional well-being in a group of atheists and agnostics, showing that scientific sources of spirituality can provide similar psychological benefits as religious spirituality (Study 2). Finally, Spirituality of Science predicted stronger engagement and recall of scientific information (Study 3). Results provide support for an experience of spirituality related to science, with benefits for meaning, well-being, and learning.
Student-centred learning forms a major driver behind educational policy and practice in the modern day. With a drive towards embracing the possibilities of technology within the classroom, especially ...digital video games, it is vital to have an understanding of where such games are delivering and where their potential has yet to be explored. With this in mind, it is important to survey the existing literature to establish the level to which the promise of student-centred learning is being delivered through digital video games. This study presents a conceptual framework based upon a systematic literature review of developments in student-centred digital game–based learning, and seeks to establish the extent to which all tenets of student-centred learning and principles of digital game–based learning are embraced within such applications. A thematic analysis identifies the common themes of game and intervention design while integrating and conceptually linking the key concepts of student-centred learning and digital game–based learning. This leads to the development of a conceptual framework allowing classification of the literature according to common themes. Inclusion criteria include the presence of student-centred learning concepts, with a game-based focus including specifically digital video games. Inclusion was limited to papers published since 2007. The literature analysis identifies a number of themes; these were primarily the types of player engagement: single player, mixed and multiplayer, along with principles of game design and the key tenets of student-centred learning. A preponderance of games and interventions utilising single player experiences and focusing on implementing the active learning tenet of student-centred learning were observed. Areas relating to multiplayer engagements and the social aspects of student-centred learning such as mutual respect receive comparatively less attention in games and research. In order to fully embrace the possibilities offered by student-centred digital game–based learning, it is important not to neglect lessons learned in the development of student-centred learning to its current state. Aspects such as peer-based learning and building relationships between students and teachers have been found important in traditional learning and must be investigated and adapted to new media, including games, as new technologies enter the educational mainstream. Further research into the effects of designing games around these multiplayer aspects, and better defining the role of teachers and educational staff in digital game–based learning, may demonstrate ways to develop and create educational experiences that better engage and prepare students.
Following a direct data-driven approach, we propose a robust encoder-decoder Gated Recurrent Unit (GRU), GRUδ, for optimal discrete option hedging. The proposed GRUδ utilizes the Black-Scholes model ...as a pre-trained model and incorporates sequential information and feature selection. Using the S&P 500 index European option market data, we demonstrate that the weekly and monthly hedging performance of the proposed GRUδ significantly surpasses that of the data-driven minimum variance (MV) method, the regularized kernel data-driven model, and the SABR-Bartlett method. In addition, the daily hedging performance of the proposed GRUδ also surpasses that of MV methods based on parametric models, the kernel method, and SABR-Bartlett method.
The solid Earth strains in response to the gravitational pull from the Moon, Sun, and other planetary bodies. Measuring the flexure of geologic material in response to these Earth tides provides ...information about the geomechanical properties of rock and sediment. Such measurements are particularly useful for understanding dilation of faults and fractures in competent rock. A new approach to measuring earth tides using fiber optic distributed acoustic sensing (DAS) is presented here. DAS was originally designed to record acoustic vibration through the measurement of dynamic strain on a fiber optic cable. Here, laboratory experiments demonstrate that oscillating strain can be measured with DAS in the microHertz frequency range, corresponding to half-day (M
) lunar tidal cycles. Although the magnitude of strain measured in the laboratory is larger than what would be expected due to earth tides, a clear signal at half-day period was extracted from the data. With the increased signal-to-noise expected from quiet field applications and improvements to DAS using engineered fiber, earth tides could potentially be measured in deep boreholes with DAS. Because of the distributed nature of the sensor (0.25 m measurement interval over kilometres), fractures could be simultaneously located and evaluated. Such measurements would provide valuable information regarding the placement and stiffness of open fractures in bedrock. Characterization of bedrock fractures is an important goal for multiple subsurface operations such as petroleum extraction, geothermal energy recovery, and geologic carbon sequestration.
Tools for noninvasively modulating neural signaling in peripheral organs will advance the study of nerves and their effect on homeostasis and disease. Herein, we demonstrate a noninvasive method to ...modulate specific signaling pathways within organs using ultrasound (U/S). U/S is first applied to spleen to modulate the cholinergic anti-inflammatory pathway (CAP), and US stimulation is shown to reduce cytokine response to endotoxin to the same levels as implant-based vagus nerve stimulation (VNS). Next, hepatic U/S stimulation is shown to modulate pathways that regulate blood glucose and is as effective as VNS in suppressing the hyperglycemic effect of endotoxin exposure. This response to hepatic U/S is only found when targeting specific sub-organ locations known to contain glucose sensory neurons, and both molecular (i.e. neurotransmitter concentration and cFOS expression) and neuroimaging results indicate US induced signaling to metabolism-related hypothalamic sub-nuclei. These data demonstrate that U/S stimulation within organs provides a new method for site-selective neuromodulation to regulate specific physiological functions.
A healthy immune system results from a balance of stimulatory and inhibitory pathways that allow effective responses to acute insults, without descending into chronic inflammation. Failed homeostasis ...is characteristic of autoimmune diseases such as systemic lupus erythematosus. Although HMGB1 induces proinflammatory M1-like macrophage differentiation, we describe a mechanism by which C1q modulates this activity and collaborates with HMGB1 to induce the differentiation of monocytes to anti-inflammatory M2-like macrophages. These anti-inflammatory macrophages are unresponsive to dendritic cell induction factors, effectively removing them from participation in an adaptive immune response. This pathway is mediated through a complex with RAGE and LAIR-1 and depends on relative levels of C1q and HMGB1. Importantly, these data provide insight into a homeostatic mechanism in which C1q and HMGB1 can cooperate to terminate inflammation, and which may be impaired in C1q-deficient patients with autoimmune disease.
•C1q can form a multimolecular signaling complex with HMGB1, RAGE, and LAIR-1 in lipid rafts.•C1q and HMGB1 together promote monocytes to differentiate to an anti-inflammatory phenotype.
In this paper, we state and prove two Fraïssé-style results that cover existence and uniqueness properties for twelve of the eighteen different notions of homomorphism–homogeneity as introduced by ...Lockett and Truss, and provide forward directions and implications for the remaining six cases. Following these results, we completely determine the extent to which the countable homogeneous undirected graphs (as classified by Lachlan and Woodrow) are homomorphism–homogeneous; we also provide some insight into the directed graph case.
The psychology of nonbelievers Uzarevic, Filip; Coleman, Thomas J.
Current opinion in psychology,
08/2021, Letnik:
40
Journal Article
Recenzirano
Odprti dostop
•Nonbelief relates to open-minded and analytic thinking styles, which likely interacts with cultural influences.•Nonbelievers endorse a variety of beliefs and worldviews, such as rationalistic and ...humanistic ideologies that may serve compensatory functions.•Nonbelievers report meaningful and healthy lives, and the (non)religion-health curvilinear relationship is supported across various contexts.•Nonbelievers can show prejudice toward ideological opponents, but its scope is contextual and limited.
Contrary to some conceptualizations, nonbelievers are more than simply those scoring low on religiosity scales. They seem to be characterized by analytic, flexible, and open-minded social-cognitive attributes, although this may interact with sociocultural levels of religiosity. This paper demonstrates that nonbelief, at least in the West, tends to coincide with specific worldviews, namely valuing rationality and science, as well as humanistic and liberal values. Furthermore, nonbelievers seem to parallel believers in various indicators of health. Finally, as all ideologists, nonbelievers may hold prejudicial attitudes toward groups perceived as threatening their (secular) worldviews, although this has some limits. Global increases in secularity make the nascent psychological study of nonbelievers and nonreligious worldviews an important research programme.
Variable annuity (VA) with embedded guarantees have rapidly grown in popularity around the world in recent years. Valuation of VAs has been studied extensively in past decades. However, most of the ...studies focus on a single contract. These methods can be extended neither to valuate nor to manage the risk of a large variable annuity portfolio due to the computational complexity. In this paper, we propose an efficient moment matching machine learning method to solve this problem. This method is proved to be a good candidate for risk management in terms of the speed of and the complexity of computing the annual dollar deltas, VaRs and CVaRs for a large variable annuity portfolio whose contracts are over a period of 25 years. There are two stages for our method. First, we select a small number of contracts and propose a moment matching Monte Carlo method based on the Johnson curve, rather than the well known nested simulations, to compute the annual dollar deltas, VaRs and CVaRs for each selected contract. Then, these computed results are used as a training set for well known machine learning methods, such as regression tree, neural network and so on. Afterwards, the annual dollar deltas, VaRs and CVaRs for the entire portfolio are predicted through the trained machine learning method. Compared to other existing methods Bauer et al. (2008); Gan (2013); Gan and Lin (2015), our method is very efficient and accurate. Finally, our test results support our claims.
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