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SummaryBackgroundPublic health efforts to determine population infection rates from coronavirus disease 2019 (COVID-19) have been hampered by limitations in testing capabilities and the large shares of mild and asymptomatic cases. We developed a methodology that corrects observed positive test rates for non-random sampling to estimate population infection rates across U.S. states from March 31 to April 7.MethodsWe adapted a sample selection model that corrects for non-random testing to estimate population infection rates. The methodology compares how the observed positive case rate vary with changes in the size of the tested population, and applies this gradient to infer total population infection rates. Model identification requires that variation in testing rates be uncorrelated with changes in underlying disease prevalence. To this end, we relied on data on day-to-day changes in completed tests across U.S. states for the period March 31 to April 7, which were primarily influenced by immediate supply-side constraints. We used this methodology to construct predicted infection rates across each state over the sample period. We also assessed the sensitivity of the results to controls for state-specific daily trends in infection rates.ResultsThe median population infection rate over the period March 31 to April 7 was 0.9% (IQR 0.64 1.77). The three states with the highest prevalence over the sample period were New York (8.5%), New Jersey (7.6%), and Louisiana (6.7%). Estimates from mod-els that control for state-specific daily trends in infection rates were virtually identical to the baseline findings. The estimates imply a nationwide average of 12 population infections per diagnosed case. We found a negative bivariate relationship (corr. = -0.51) between total per capita state testing and the ratio of population infections per diagnosed case.InterpretationThe effectiveness of the public health response to the coronavirus pandemic will depend on timely information on infection rates across different regions. With increasingly available high frequency data on COVID-19 testing, our methodology could be used to estimate population infection rates for a range of countries and subnational districts. In the United States, we found widespread undiagnosed COVID-19 infection. Expansion of rapid diagnostic and serological testing will be critical in preventing recurrent unobserved community transmission and identifying the large numbers individuals who may have some level of viral immunity.FundingSocial Sciences and Humanities Research Council.

How do people decide whether to incur costs to increase their likelihood of success? In investigating this question, we offer a theory called prospective outcome bias. According to this theory, people tend to make decisions that they expect to feel good about after the outcome has been realized. Because people expect to feel best about decisions that are followed by successes-even when the decisions did not cause those successes-they will pay more to increase their chances of success when success is already likely (e.g., people will pay more to increase their probability of success from 80% to 90% than from 10% to 20%). We find evidence for prospective outcome bias in nine experiments. In Study 1, we establish that people evaluate costly decisions that precede successes more favorably than costly decisions that precede failures, even when the decisions did not cause the outcome. Study 2 establishes, in an incentive-compatible laboratory setting, that people are more motivated to increase higher chances of success. Studies 3-5 generalize the effect to other contexts and decisions and Studies 6-8 indicate that prospective outcome bias causes it (rather than regret aversion, waste aversion, goals-as-reference-points, probability weighting, or loss aversion). Finally, in Study 9, we find evidence for another prediction of prospective outcome bias: people prefer small increases in the probability of large rewards (e.g., a 1% improvement in their chances of winning $100) to large increases in the probability of small rewards (e.g., a 10% improvement in their chances of winning $10). (PsycInfo Database Record (c) 2020 APA, all rights reserved).

From 1930 to 1960 rural communities, mainly in the U.S. South and Southwest, gained access to electricity. In addition to lights, the benefits included easier clothes washing, refrigeration, and pumped water. This article uses differences in the timing of electricity access across rural counties to study the effects on infant mortality and fertility. Rural electrification led to substantial reductions in infant mortality but had little effect on women's fertility. The increase in electricity access between 1930 and 1960 can account for 15 to 19 percent of the decline in rural infant mortality during this period.

Susan Wolf defines a meaningful life as one that is somewhat successfully engaged in promoting positive value. I grant this claim; however, I disagree with Wolf’s theory about why we desire meaningfulness, so understood. She suggests that the human desire for meaningfulness is derived from an awareness of ourselves as equally insignificant in the universe and a resulting anti-solipsistic concern for promoting goodness outside the boundaries of our own lives. I accept that this may succeed in explaining why people want to engage in projects that happen to be meaningful. Nevertheless, I argue that Wolf fails to explain why people have a desire for meaningfulness itself. In other words, she has told us one reason we may be motivated to promote positive value, but not why we personally want to be the people who promote it—why we think it is a good thing that meaningful acts be done, but not why we want them to be our meaningful acts. In detailing my response, I follow Wolf in relating our desire for meaningfulness to a kind of love-based motivation. However, I argue that it has more in common with a selfish form of love than the altruistic kind of love proposed by Wolf. Finally, I suggest an alternative explanation which I believe can more fully account for our desire for meaningfulness: the prospect of disappearing from the universe without a trace makes us anxious, so we pursue meaningful achievements in an attempt to make our own physical deaths less final.

In this paper, I assess the claim that death renders life absurd. First, I characterize absurdity as something we perceive in situations involving extreme disharmonies which strike us as unexpected or unacceptable. Next, I outline several potential disharmonies which death might introduce into our existence (such as the disharmony between our dignity and capacities, and the undignified annihilation which death promises), but suggest that these examples need not be seen as necessarily absurd; there are perspectives available to us from which these facts can appear to be acceptable aspects of life. Finally, I consider a more problematic case of absurdity—that human beings allegedly fail to grasp the truth of their mortality—but suggest that the underlying disharmony here can be eliminated provided we develop an authentic attitude toward death (and that this is possible, despite some objections). In short, I argue that none of the most obvious potential absurdities which might arise from our mortality are strong enough to entail the claim that death inevitably renders life absurd, at least on one plausible and interesting interpretation of that claim.

Despite well-meaning intentions, people rarely allocate their charitable donations in the most cost-effective way possible. The manner in which cost-effectiveness information is presented can be a contributing factor. In four studies (N = 2,725), when we inform participants of the cost of a unit of impact (e.g. the cost of a mosquito net), they perversely donate less when the cost is cheaper. This result arises because people want their donation to have a tangible impact, and when the cost of such an impact is lower, people can achieve it with a smaller donation. A remedy for this inefficiency is to express cost-effectiveness in terms of “units per dollar amount” (e.g. 5 nets provided per $10 donated), thus leaving the cost of providing one tangible item unstated and rendering it less salient as a target donation amount. Across Studies 2 and 3, we demonstrate both the inefficient use of cost-effectiveness information and the effectiveness of this remedy using incentive-compatible donations decisions about providing meals, oral rehydration therapy, deworming medication, and measles vaccines.

It is only in the last few decades that analytic philosophers in particular have begun to pay any serious attention to the topic of life’s meaning. Such philosophers, however, do not usually attempt to answer or analyse the traditional question ‘What is the meaning of life?’, but rather the subtly different question ‘What makes a life meaningful?’ and it is generally assumed that the latter can be discussed independently of the former. Nevertheless, this paper will argue that the two questions are indeed connected, and that identifying and expanding upon the most plausible analysis of the former will provide the resources necessary to determine the most plausible answer to the latter. Specifically, this paper will argue that the traditional question is simply a request for the information which constitutes a coherent answer to one or more of a certain set of questions regarding human existence that were salient to the asker. In simpler language, the meaning of life itself is the information a person needs to make sense of it. This analysis can then also be applied to individual lives, such that asking for the meaning of X’s life is an analogous request for the information necessary to make sense of that life in particular. Running with this concept of the ‘meaning’ of something as its ‘sense’, the paper then outlines an accompanying theory of ‘meaningfulness’ as ‘sensefulness’: a measure of the richness of certain aspects of the life, multiplied by their intelligibility.

While a robust literature explores the antecedents of trust in organizations, thus far, none has addressed how and why the nature of trust differs across relationships. In the present research, we ...

Disparities in cross-city pandemic severity during the 1918 Influenza Pandemic remain poorly understood. This paper uses newly assembled historical data on annual mortality across 438 U.S. cities to explore the determinants of pandemic mortality. We assess the role of three broad factors: i) pre-pandemic population health and poverty, ii) air pollution, and iii) the timing of onset and proximity to military bases. Using regression analysis, we find that cities in the top tercile of the distribution of pre-pandemic infant mortality had 21 excess deaths per 10,000 residents in 1918 relative to cities in the bottom tercile. Similarly, cities in the top tercile of the distribution of proportion of illiterate residents had 21.3 excess deaths per 10,000 residents during the pandemic relative to cities in the bottom tercile. Cities in the top tercile of the distribution of coal-fired electricity generating capacity, an important source of urban air pollution, had 9.1 excess deaths per 10,000 residents in 1918 relative to cities in the bottom tercile. There was no statistically significant relationship between excess mortality and city proximity to World War I bases or the timing of onset. In a counterfactual analysis, the three statistically significant factors accounted for 50 percent of cross-city variation in excess mortality in 1918.

Duncan Purves and Nicolas Delon have argued that one’s life will be meaningful to the extent that one contributes to valuable states of affairs and this contribution is a result of one’s intentional actions. They then argue, contrary to some theorists’ intuitions, that non-human animals are capable of fulfilling these requirements, and that this finding might entail important things for the animal ethics movement. In this paper, I also argue that things besides human beings can have meaningful existences, but I disagree with Purves and Delon’s theory of meaning, and some of the practical implications they suggest arise from their conclusion. Specifically, I argue that Purves and Delon are wrong to suggest that intentional agency is necessary for one’s life to be meaningful; contributing to valuable states of affairs can be sufficient by itself. Purves and Delon’s objection to such a claim is that it would allow even inanimate objects’ existences to count as meaningful. However, while I accept this consequence, I argue that it only seems counterintuitive because of two false beliefs they appear to hold: that some X cannot have a meaningful existence without that meaning (a) making X better off or (b) giving X reasons for pride.

Electrification among American farm households increased from less than 10 percent to nearly 100 percent over a three decade span, 1930–1960. We exploit the historical rollout of the U.S. power grid to study the short- and long-run impacts of rural electrification on local economies. In the short-run, rural electrification led to increases in agricultural employment, rural farm population, and rural property values, but there was little impact on the local non-agriculture economy. Benefits exceeded historical costs, even in rural areas with low population density. As for the long run, rural counties that gained early access to electricity experienced increased economic growth that persisted for decades after the country was fully electrified. In remote rural areas, local development was driven by an expansion in the agricultural sector. Meanwhile in rural counties near metropolitan areas, long-run population growth coincided with increases in housing costs and decreases in agricultural employment, suggesting that rural electrification stimulated suburban expansion.

AIM: To demonstrate a direct inhibitory effect of cigarette smoke exposure on paraoxonase 1 activity in a murine in vivo model. METHODS: At 8 weeks old, we randomized 10 C57/bl6 mice to an environment consisting of either filtered air or cigarette smoke for 6 months. Smoke exposure (7 hours per day, 5 days per week) was standardized using a model TE-10 smoking machine and adjusted to maintain constant sidestream and mainstream smoke. After 6 months of exposure, we assessed differences in lung air space, cholesterol, lipid, and lipoprotein profiles, as well as paraoxonase activity in mice exposed to cigarette smoke extract compared to unexposed control mice. RESULTS: Cigarette smoke exposure by the protocol used was sufficient to result in pathologic changes in lung architecture consistent with emphysema. Specifically, we observed that mice exposed to cigarette smoke had a significantly higher mean linear chord length compared to animals that were exposed to filtered air (p

Pollution is a common byproduct of economic activity. Although policymakers should account for both the benefits and the negative externalities of polluting activities, it is difficult to identify those who are harmed and those who benefit from them. To overcome this challenge, our paper uses a novel dataset on the mid-20th century expansion of the U.S. power grid to study the costs and the benefits of coal-fired electricity generation. The empirical analysis exploits the timing of coal-fired power plant openings and annual variation in plant-level coal consumption from 1938 to 1962, when emissions were virtually unregulated. Pollution from the burning of coal for electricity generation is shown to have quantitatively important and nonlinear effects on county-level infant mortality rates. By 1962, it was responsible for 3,500 infant deaths per year, over one death per thousand live births. These effects are even larger at lower levels of coal consumption. We also find evidence of clear tradeoffs associated with coal-fired electricity generation. For counties with low access to electricity in the baseline, increases in local power plant coal consumption reduced infant mortality and increased housing values and rental prices. For counties with near universal access to electricity in the baseline, increases in coal consumption by power plants led to higher infant mortality rates, and lower housing values and rental prices. These results highlight the importance of considering both the costs and benefits of polluting activities, and suggest that demand for policy intervention may emerge only when the negative externalities are significantly larger than the perceived benefits.

The 1918 Influenza Pandemic killed millions worldwide and hundreds of thousands in the United States. This article studies the impact of air pollution on pandemic mortality. The analysis combines a panel dataset on infant and all-age mortality with a novel measure of air pollution based on the burning of coal in a large sample of U.S. cities. We estimate that air pollution contributed significantly to pandemic mortality. Cities that used more coal experienced tens of thousands of excess deaths in 1918 relative to cities that used less coal with similar pre-pandemic socioeconomic conditions and baseline health. Factors related to poverty, public health, and the timing of onset also affected pandemic mortality. The findings support recent medical evidence on the link between air pollution and influenza infection, and suggest that poor air quality was an important cause of mortality during the pandemic.

Background— Cocaine is a major cause of acute coronary syndrome, especially in young adults; however, the mechanistic underpinning of cocaine-induced acute coronary syndrome remains limited. Previous studies in animals and in patients undergoing cardiac catheterization suggest that cocaine constricts coronary microvessels, yet direct evidence is lacking. Methods and Results— We used myocardial contrast echocardiography to test the hypothesis that cocaine causes vasoconstriction in the human coronary microcirculation. Measurements were performed at baseline and after a low, nonintoxicating dose of intranasal cocaine (2 mg/kg) in 10 healthy cocaine-naïve young men (median age, 32 years). Postdestruction time-intensity myocardial contrast echocardiography kinetic data were fit to the equation y=A(1−e −βt ) to quantify functional capillary blood volume (A), microvascular flow velocity (β), and myocardial perfusion (A×β). Heart rate, mean arterial pressure, and left ventricular work (2-dimensional echocardiography) were measured before and 45 minutes after cocaine. Cocaine increased mean arterial pressure (by 14±2 mm Hg [mean±SE]), heart rate (by 8±3 bpm), and left ventricular work (by 50±18 mm Hg·mL −1 ·bpm −1 ). Despite the increases in these determinants of myocardial oxygen demand, myocardial perfusion decreased by 30% (103.7±9.8 to 75.9±10.8 arbitrary units [AU]/s; P P Conclusions— In healthy cocaine-naïve young adults, a low-dose cocaine challenge evokes a sizeable decrease in myocardial perfusion. Moreover, the predominant effect is to decrease myocardial capillary blood volume rather than microvascular flow velocity, suggesting a specific action of cocaine to constrict terminal feed arteries.

In largely distributed clusters, computing nodes are geographically deployed in various computing sites. Information processed in a distributed cluster is shared among a group of distributed processes or users by virtue of messages passing protocols (e.g. message passing interface — MPI) running on the Internet. Because of the open accessible nature of the Internet, data encryption for these large-scale distributed clusters becomes a non-trivial and challenging problem. To address this issue, we enhanced the security of the MPI (Message Passing Interface) protocol by encrypting and decrypting messages sent and received among computing nodes. In this study we focused on MPI rather than other protocols because MPI is one of the most popular communication protocols for cluster computing environments. From among a variety of MPI implementations, we picked MPICH2 developed by the Argonne National Laboratory. The design goal of MPICH2 — a widely used MPI implementation — is to combine portability with high performance. We integrated encryption algorithms into the MPICH2 library so that data confidentiality of MPI applications could be readily preserved without a need to change the source codes of the MPI applications. since we provide a security enhanced MPI-library with the standard MPI interfact, data communications of a conventional MPI program can be secured without converting the program into the corresponding secure version. We used Sandia Micro Benchmark and Intel MPI Benchmarks to evaluate and compared the performance of original MPICH2 and Enhanced Security MPICH2. According to the performance evaluation, ES-MPICH2 provides secured Message Passing Interface by sacrificing reasonable system performance.

A novel laboratory exercise is presented that demonstrates a man-in-the-middle (MITM) attack on web browser sessions that use the "secure" HTTPS protocol. The exercise presents the students with six different scenarios and challenges the student to determine if a MITM attack is taking place when they browse any website using the HTTPS protocol. Each scenario is defined in a single computer running Microsoft Windows Server with VMWare Workstation as an application. The virtual machines running in VMWare are connected and configured in such a way that a MITM attack is possible. Students log into a virtual machine running Microsoft Windows XP and use four different browsers, Internet Explorer, Mozilla Firefox, Opera, and Google Chrome to browse the Internet and go to sites secured with HTTPS. Depending on the scenario, the MITM attack may or may not be present, and a malicious root certificate may or may not be installed in the web browser. Students are challenged to explain the browser behavior and to determine if a MITM attack is under way. The Windows Server images for the six scenarios can be automatically scheduled to be loaded on available blade servers based on reservations made by the students. Students then use the Remote Desktop Protocol to remotely log into the Windows Server host machine and perform the exercises. This exercise demonstrates the chain of trust of certificates in PKI, the importance of the authenticity of root certificates, the behavior of different web browsers under a MITM attack, and the ability to perform an undetectable MITM attack if the private key corresponding to a root certificate is know by the attacker. The experience of using this laboratory exercise during the spring semester of 2010 will be discussed along with student reactions.

Background Gene duplication has had a major impact on genome evolution. Localized (or tandem) duplication resulting from unequal crossing over and whole genome duplication are believed to be the two dominant mechanisms contributing to vertebrate genome evolution. While much scrutiny has been directed toward discerning patterns indicative of whole-genome duplication events in teleost species, less attention has been paid to the continuous nature of gene duplications and their impact on the size, gene content, functional diversity, and overall architecture of teleost genomes. Results Here, using a Markov clustering algorithm directed approach we catalogue and analyze patterns of gene duplication in the four model teleost species with chromosomal coordinates: zebrafish, medaka, stickleback, and Tetraodon. Our analyses based on set size, duplication type, synonymous substitution rate (Ks), and gene ontology emphasize shared and lineage-specific patterns of genome evolution via gene duplication. Most strikingly, our analyses highlight the extraordinary duplication and retention rate of recent duplicates in zebrafish and their likely role in the structural and functional expansion of the zebrafish genome. We find that the zebrafish genome is remarkable in its large number of duplicated genes, small duplicate set size, biased Ks distribution toward minimal mutational divergence, and proportion of tandem and intra-chromosomal duplicates when compared with the other teleost model genomes. The observed gene duplication patterns have played significant roles in shaping the architecture of teleost genomes and appear to have contributed to the recent functional diversification and divergence of important physiological processes in zebrafish. Conclusions We have analyzed gene duplication patterns and duplication types among the available teleost genomes and found that a large number of genes were tandemly and intrachromosomally duplicated, suggesting their origin of independent and continuous duplication. This is particularly true for the zebrafish genome. Further analysis of the duplicated gene sets indicated that a significant portion of duplicated genes in the zebrafish genome were of recent, lineage-specific duplication events. Most strikingly, a subset of duplicated genes is enriched among the recently duplicated genes involved in immune or sensory response pathways. Such findings demonstrated the significance of continuous gene duplication as well as that of whole genome duplication in the course of genome evolution.