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Author(s):  
Francisco J Beltrán Tapia ◽  
Francisco J Marco-Gracia

Abstract Relying on longitudinal micro data from rural Spain between 1750 and 1950, this article evidences that families mortally neglected a significant fraction of their female babies. Firstly, baptism records exhibited exceptionally high sex ratios at birth until the late nineteenth century. Secondly, having no previous male siblings increased the probability of male baptisms. Likewise, this same feature, together with the number of siblings alive, also increased female mortality during the first day of life. These findings are concentrated at higher parities and among landless and semi-landless families. Lastly, under-registration cannot explain these patterns affecting female mortality shortly after birth.


2021 ◽  
pp. 146144482110548
Author(s):  
Marcelo Santos ◽  
Magdalena Saldaña ◽  
Ksenia Tsyganova

Internet, social media, and app shutdowns have become frequent, not only in authoritarian states but also in emerging and fragile democracies. As Russian authorities enforced a legal blockage to Instant Messenger Telegram during the past 2 years, many users kept using the app seamlessly thanks to what we call a subversive affordance: a built-in proxy functionality that allows users to seamlessly circumvent the blockage. We claim it is subversive because it allows users to overcome the blockage as the consequence of the app’s development, with a significant fraction of users who did not have to take action to bypass the blockage. By conducting an online survey and performing a meta-cluster analysis, we found a group we labeled the undeprived: people that, despite presenting traits frequently associated with digital divides—such as gender, age, and low levels of digital skills—were able to keep using the app.


2021 ◽  
Author(s):  
Eduardo P. C. Rocha ◽  
David Bikard

Prokaryotes have numerous mobile genetic elements (MGE) that mediate horizontal gene transfer between cells. These elements can be costly, even deadly, and cells use numerous defense systems to filter, control or inactivate them. Surprisingly, many phages, conjugative plasmids, and their parasites, phage satellites or mobilizable plasmids, encode defense systems homologous to those of bacteria. They constitute a significant fraction of the systems found in bacterial genomes. As components of MGEs, they have presumably evolved to provide them, not the cell, adaptive functions that may be defensive, offensive, or both. This sheds new light on the role, effect, and fate of the so called “cellular defense systems”, whereby they are not merely microbial defensive weapons in a two-partner arms race, but tools of intragenomic conflict between multiple genetic elements with divergent interests. It also raises many intriguing questions.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tuan M. Pham ◽  
Andrew C. Alexander ◽  
Jan Korbel ◽  
Rudolf Hanel ◽  
Stefan Thurner

AbstractRecent attempts to understand the origin of social fragmentation on the basis of spin models include terms accounting for two social phenomena: homophily—the tendency for people with similar opinions to establish positive relations—and social balance—the tendency for people to establish balanced triadic relations. Spins represent attribute vectors that encode G different opinions of individuals whose social interactions can be positive or negative. Here we present a co-evolutionary Hamiltonian model of societies where people minimise their individual social stresses. We show that societies always reach stationary, balanced, and fragmented states, if—in addition to homophily—individuals take into account a significant fraction, q, of their triadic relations. Above a critical value, $$q_c$$ q c , balanced and fragmented states exist for any number of opinions.


2021 ◽  
Author(s):  
Takuya Tada ◽  
Hao Zhou ◽  
Marie I Samanovic ◽  
Belinda M Dcosta ◽  
Amber Cornelius ◽  
...  

The increasing prevalence of SARS-CoV-2 variants has raised concerns regarding possible decreases in vaccine efficacy. Here, neutralizing antibody titers elicited by mRNA-based and an adenoviral vector-based vaccine against variant pseudotyped viruses were compared. BNT162b2 and mRNA-1273-elicited antibodies showed modest neutralization resistance against Beta, Delta, Delta plus and Lambda variants whereas Ad26.COV2.S-elicited antibodies from a significant fraction of vaccinated individuals were of low neutralizing titer (IC50 <50). The data underscore the importance of surveillance for breakthrough infections that result in severe COVID-19 and suggest the benefit of a second immunization following Ad26.COV2.S to increase protection against the variants.


2021 ◽  
Vol 111 (7) ◽  
pp. 2152-2178
Author(s):  
S. Nageeb Ali ◽  
Maximilian Mihm ◽  
Lucas Siga ◽  
Chloe Tergiman

We study two-player games where one-sided asymmetric information can lead to either adverse or advantageous selection. We contrast behavior in these games with settings where both players are uninformed. We find stark differences, suggesting that subjects do account for endogenous selection effects. Removing strategic uncertainty increases the fraction of subjects who account for selection. Subjects respond more to adverse than advantageous selection. Using additional treatments where we vary payoff feedback, we connect this difference to learning. We also observe a significant fraction of subjects who appear to understand selection effects but do not apply that knowledge. (JEL C92, D82, D91)


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lev Muchnik ◽  
Elad Yom-Tov ◽  
Nir Levy ◽  
Amir Rubin ◽  
Yoram Louzoun

AbstractEmpirical studies show that epidemiological models based on an epidemic’s initial spread rate often fail to predict the true scale of that epidemic. Most epidemics with a rapid early rise die out before affecting a significant fraction of the population, whereas the early pace of some pandemics is rather modest. Recent models suggest that this could be due to the heterogeneity of the target population’s susceptibility. We study a computer malware ecosystem exhibiting spread mechanisms resembling those of biological systems while offering details unavailable for human epidemics. Rather than comparing models, we directly estimate reach from a new and vastly more complete data from a parallel domain, that offers superior details and insight as concerns biological outbreaks. We find a highly heterogeneous distribution of computer susceptibilities, with nearly all outbreaks initially over-affecting the tail of the distribution, then collapsing quickly once this tail is depleted. This mechanism restricts the correlation between an epidemic’s initial growth rate and its total reach, thus preventing the majority of epidemics, including initially fast-growing outbreaks, from reaching a macroscopic fraction of the population. The few pervasive malwares distinguish themselves early on via the following key trait: they avoid infecting the tail, while preferentially targeting computers unaffected by typical malware.


2021 ◽  
Author(s):  
TUAN PHAM ◽  
Andrew Alexander ◽  
Jan Korbel ◽  
Rudolf Hanel ◽  
Stefan Thurner

Abstract Recent attempts to understand the origin of social fragmentation on the basis of spin models include terms accounting for two social phenomena: homophily—the tendency for people with similar opinions to establish positive relations—and social balance—the tendency for people to establish balanced triadic relations. Spins represent attribute vectors that encode G different opinions of individuals; social interactions between individuals can be positive or negative. Here we present a co-evolutionary Hamiltonian framework that minimizes individuals’ social stress in social networks that have finite connectivity and people with a small number of attributes. We show that such systems always reach stationary, balanced, and fragmented states, if –in addition to homophily– individuals take into account a significant fraction, q, of their triadic relations. Above a critical value, qc, balanced and fragmented states exist for any number of opinions.


2021 ◽  
Vol 104 (2) ◽  
pp. 003685042110283
Author(s):  
Lucia Maria Almeida Braz ◽  
Roozbeh Tahmasebi ◽  
Antonio Charlys da Costa ◽  
Steven S Witkin

Despite being among the world’s leaders in scientific output, Brazil ranks 66th among countries in the production of reagents and supplies needed for state-of-the-art scientific analyses. The production of needed reagents and equipment for experimental analyses and patient diagnostics is sorely lacking within Brazil and explicit in this pandemic period caused by SARS-CoV-2. A significant fraction of resources from Brazilian funding agencies is now being transferred to companies in other countries for the purchase of essential scientific-related products. Is this sustainable? Therefore it is necessary to draw the attention of all the world and Brazilian society about this situation


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