Miracle-dz/UniFAR-FTUs huggingface dataset:
Hippocampal CA1 Ripples as Inhibitory Transients

Memories are stored and consolidated as a result of a dialogue between the hippocampus and cortex during sleep. Neurons active during behavior reactivate in both structures during sleep, in conjunction with characteristic brain oscillations that may form the neural substrate of memory consolidation. In the hippocampus, replay occurs within sharp wave-ripples: short bouts of high-frequency activity in area CA1 caused by excitatory activation from area CA3. In this work, we develop a computational model of ripple generation, motivated by in vivo rat data showing that ripples have a broad frequency distribution, exponential inter-arrival times and yet highly non-variable durations. Our study predicts that ripples are not persistent oscillations but result from a transient network behavior, induced by input from CA3, in which the high frequency synchronous firing of perisomatic interneurons does not depend on the time scale of synaptic inhibition. We found that noise-induced loss of synchrony among CA1 interneurons dynamically constrains individual ripple duration. Our study proposes a novel mechanism of hippocampal ripple generation consistent with a broad range of experimental data, and highlights the role of noise in regulating the duration of input-driven oscillatory spiking in an inhibitory network.
Vaccination against atherosclerosis: science or fiction?

Atherosclerosis bears many similarities to inflammatory/autoimmune diseases like rheumatoid arthritis and multiple sclerosis (MS). 1,2⇓ Compelling data from experimental models show that such diseases may be treated by vaccination. Will it be possible to attack atherosclerotic cardiovascular disease with the same approach? Several studies have shown positive effects of immunization with antigenic LDL preparations,3–6⇓⇓⇓ and a report in this issue of Circulation demonstrates a protective effect of oral and nasal immunization with another antigen, heat shock protein 65 (HSP65). 7 See p 1708 Atherosclerosis is a complex disease that involves several different cell types and their molecular products. The immune system is even more complicated, with many cell types, hundreds of cytokines, and literally millions of different antigens. The work has just begun to sort out the ones involved in atherosclerosis among this myriad of molecules and cells. Two gene-targeted murine models of atherosclerosis, the apolipoprotein E–knockout and the LDL-receptor knockout mice, have proved to be useful for these investigations. Several lines of evidence point to the CD4+ T cell as a “bad guy” in atherogenesis. If these cells are transferred from immunocompetent to immune deficient apolipoprotein E–knockout mice, disease increases drastically.8 The CD4+ cell is also the most prevalent T cell in the human atherosclerotic lesion, and exhibits reactivity to putative “athero-antigens. ”2 CD4+ T cells can be divided into at least 2 different subsets that counterbalance each other.9 The most prevalent type of CD4+ T cells is called Th1; it induces macrophage activation and promotes inflammation. Th1 cells accomplish this largely by secreting interferon-γ, an important proinflammatory cytokine, which is produced in the human atherosclerotic lesion and accelerates atherosclerosis in mice.2 Counteracting this subset, the Th2 cell suppresses inflammation and dampens macrophage activity. Several different cytokines may be responsible for …
Using social media to identify events

We present a method to automatically detect and identify events from social media sharing web sites. Our approach is based on the observation that many photos and videos are taken and shared when events occur. We select 9 venues across the globe that demonstrate a significant activity according to the EventMedia dataset and we thoroughly evaluate our approach against an official ground truth obtained directly by scraping the event venues' web sites. The results show our ability to not only detect events with high accuracy but also mine and identify events that have not been published in popular event directories such as Last.fm, Eventful or Upcoming. In addition to the textual identification of events, we show how we can build visual summaries of past events providing viewers with a more compelling feeling of the event's atmosphere.
Venture Capitalists as Principals: Contracting, Screening, and Monitoring

Theoretical work on the principal-agent problem in financial contracting focuses on the conflicts of interest between an agent / entrepreneur with a venture that needs financing, and a principal / investor providing funds for the venture. Theory has identified three primary ways that the investor / principal can mitigate these conflicts - structuring financial contracts, pre-investment screening, and post-investment monitoring and advising. In this paper, we describe recent empirical work and its relation to theory for one prominent class of principals venture capitalists (VCs). The empirical studies indicate that VCs attempt to mitigate principal-agent conflicts in the three ways suggested by theory. The evidence also shows that contracting, screening, and monitoring are closely interrelated. In screening, the VCs identify areas where they can add value through monitoring and support. In contracting, the VCs allocate rights in order to facilitate monitoring and minimize the impact of identified risks. Also, the equity allocated to VCs provides incentives to engage in costly support activities that increase upside values, rather than just minimizing potential losses. There is room for future empirical research to study these activities in greater detail for VCs, for other intermediaries such as banks, and within firms.
ROBUST A-POSTERIORI ESTIMATORS FOR MULTILEVEL DISCRETIZATIONS OF REACTION – DIFFUSION SYSTEMS

We define a multilevel finite element discretization for a coupled stationary reaction– diffusion system in which each component can be defined on a separate grid. We prove convergence of the scheme and propose residual a-posteriori estimators for the error in the natural energy norm for the system. The estimators are robust in the coefficients of the system. We prove upper and lower bounds and illustrate the theory with numerical experiments.
A pseudo‐breakup observation: Localized current wedge across the postmidnight auroral oval

[1] This study presents a detailed description and analysis of a pseudo-breakup, which took place in the field of view (FOV) of the Magnetometers–Ionospheric Radars–All-sky Cameras Large Experiment (MIRACLE) network (IMAGE magnetometers, Scandinavian Twin Auroral Radar Experiment [STARE] radars, and all-sky cameras) on 3 November 1997 at 2212 UT. The activation lasted ∼10 min, occurred during geomagnetically quiet conditions (Dst ≥ −10 nT), and was followed by a global-scale substorm about half an hour later (at 2246 UT). Both the pseudo-breakup and the substorm had onsets at times corresponding to the Wind satellite observations of interplanetary magnetic field (IMF) BZ northward turnings as delayed to the subsolar magnetopause. The auroral display of the pseudo-breakup was a mesoscale spiral with a counterclockwise winding direction. Simultaneously, STARE recorded clockwise plasma flow in the spiral surroundings. Applying the method of characteristics to the MIRACLE observations revealed that the spiral was associated with a localized current wedge (less than a few hours in MLT and about 4° in latitude), tilted in the northeast-southwest direction. The maximum upward current density at the western edge of the wedge was about 6 A/km2, which clearly exceeds the threshold of spiral buildup (2.5 A/km2) suggested by earlier theoretical studies. About an hour before the pseudo-breakup, the energy input from the solar wind to the magnetosphere (quantified by the ϵ parameter) exceeded the substorm threshold and the ionospheric conductivity was high enough to support substorm activity. Two likely reasons for the activation to remain localized were its unfavorable location in the morning side of the Harang discontinuity region and the abrupt decrease of the solar wind energy input at its onset time.
Institute for Mathematical Physics Construction of Quantum Field Theories with Factorizing S–matrices Construction of Quantum Field Theories with Factorizing S-matrices

A new approach to the construction of interacting quantum field theories on two-dimensional Minkowski space is discussed. In this program, models are obtained from a prescribed factorizing S-matrix in two steps. At first, quantum fields which are localized in infinitely extended, wedge-shaped regions of Minkowski space are constructed explicitly. In the second step, local observables are analyzed with operator-algebraic techniques, in particular by using the modular nuclearity condition of Buchholz, d'Antoni and Longo. Besides a model-independent result regarding the Reeh-Schlieder property of the vacuum in this framework, an infinite class of quantum field theoretic models with non-trivial interaction is constructed. This construction completes a program initiated by Schroer in a large family of theories, a particular example being the Sinh-Gordon model. The crucial problem of establishing the existence of local observables in these models is solved by verifying the modular nuclearity condition , which here amounts to a condition on analytic properties of form factors of observables localized in wedge regions. It is shown that the constructed models solve the inverse scattering problem for the considered class of S-matrices. Moreover, a proof of asymptotic completeness is obtained by explicitly computing total sets of scattering states. The structure of these collision states is found to be in agreement with the heuristic formulae underlying the Zamolodchikov-Faddeev algebra.
Follicular Dendritic Cells and the Persistence of HIV Infectivity: The Role of Antibodies and Fcγ Receptors1

Large quantities of HIV are found trapped on the surface of follicular dendritic cells (FDCs), and virus persists on these cells until they ultimately die. We recently found that FDCs maintain HIV infectivity for long periods in vivo and in vitro. Because FDCs trap Ags (and virus) in the form of immune complexes and are rich in FcγRs, we reasoned that Ab and FcγRs may be required for FDC-mediated maintenance of HIV infectivity. To investigate this hypothesis, HIV immune complexes were formed in vitro and incubated for increasing times with or without FDCs, after which the remaining infectious virus was determined by HIV-p24 production in rescue cultures. FDCs maintained HIV infectivity in vitro in a dose-dependent manner but required the presence of specific Ab for this activity regardless of whether laboratory-adapted or primary X4 and R5 isolates were tested. In addition, Abs against either virally or host-encoded proteins on the virion permitted FDC-mediated maintenance of HIV infectivity. We found that the addition of FDCs to HIV immune complexes at the onset of culture gave optimal maintenance of infectivity. Moreover, blocking FDC-FcγRs or killing the FDCs dramatically reduced their ability to preserve virus infectivity. Finally, FDCs appeared to decrease the spontaneous release of HIV-1 gp120, suggesting that FDC-virus interactions stabilize the virus particle, thus contributing to the maintenance of infectivity. Therefore, optimal maintenance of HIV infectivity requires both Ab against particle-associated determinants and FDC-FcγRs.
The gene encoding the cytosolic small subunit of ADP-glucose pyrophosphorylase in barley endosperm also encodes the major plastidial small subunit in the leaves.

The barley (Hordeum vulgare) gene Hv.AGP. S.1 produces two different transcripts encoding small subunits (SSUs) of ADP-glucose pyrophosphorylase (AGPase). It was shown previously that one of these transcripts, Hv.1a, encodes the cytosolic SSU in the endosperm. It is shown here that the other transcript produced from Hv.AGP. S.1, Hv.1b, encodes a plastidial SSU that is required for >90% of the AGPase activity in the leaves. Thus, both of the alternative transcripts encoded by Hv.AGP. S.1 are physiologically relevant: One is important for starch synthesis in the endosperm and the other for starch synthesis in the leaves. Although the Hv.1b transcript is abundant in embryos and present in endosperm, there is no evidence that a protein is produced from this transcript in these organs. This suggests that some, as yet unidentified, post-transcriptional control mechanism prevents the accumulation of the protein encoded by Hv.1b in embryos and endosperm but not in leaves. There is one other known gene in barley, Hv.AGP. S.2, encoding a SSU of AGPase. This gene has been shown to be responsible for the plastidial SSU in the endosperm. It is shown here that Hv.AGP. S.2 probably also makes some contribution to the SSU of AGPase in the leaves and may be responsible for most or all of the plastidial SSU in a range of non-photosynthetic plant organs including the embryo.
Prosociality, Political Identity, and Redistribution of Earned Income: Theory and Evidence

We explore the relation between social political identity and prosociality. We first construct a theoretical model to generate predictions for the behavior of players in an ultimatum game who are influenced by social political identity. Then we use a novel subject pool-registered members of British political parties - to play the ultimatum game, and test our predictions. Incomes can either be unearned and untaxed (Treatment 1) or earned, taxed, and redistributed (Treatment 2). We find that the choices of the proposers and the responders are consistent with social identity theory (higher offers and lower minimum acceptable offers to ingroup members) although proposers show quantitatively stronger social identity effects. Moving from Treatment 1 to Treatment 2, offers by proposers decline and the minimum acceptable offers by responders (both as a proportion of income) also decline by almost the same amount, suggesting shared understanding that is characteristic of social norms.
Childhood Gender Nonconformity and Children’s Past-Life Memories

Abstract Objectives: This study examines childhood gender nonconformity (GNC) in conjunction with the phenomenon in which young children describe memories of a purported previous life. Methods: In a case-control study of 469 children reporting past-life memories, we used logistic regression to examine predictors of GNC, measured by documented gender nonconforming behaviors. Results: Children who remembered a life involving a different natal sex were much more likely to exhibit GNC than children who remembered a same-sex life. Conclusions: After exploring potential explanations, we conclude that past-life memories represent a novel factor that may be associated with the development of GNC.
ESTIMATING BLACK HOLE MASSES IN ACTIVE GALAXIES USING THE H α EMISSION LINE

It has been established that virial masses for black holes in low-redshift active galaxies can be estimated from measurements of the optical continuum strength and the width of the broad Hβ line. Under various circumstances, however, both of these quantities can be challenging to measure or can be subject to large systematic uncertainties. To mitigate these difficulties, we present a new method for estimating black hole masses. From analysis of a new sample of broad-line active galactic nuclei, we find that Hα luminosity scales almost linearly with optical continuum luminosity and that a strong correlation exists between Hα and Hβ line widths. These two empirical correlations allow us to translate the standard virial mass system to a new one based solely on observations of the broad Hα emission line. Subject headings: galaxies: active — galaxies: jets — galaxies: nuclei — galaxies: Seyfert — quasars: general
Evidence that Gsta4 modifies susceptibility to skin tumor development in mice and humans.

BACKGROUND The incidence of nonmelanoma skin cancer (NMSC) is equivalent to that of all other cancers combined. Previously, we mapped the 12-O-tetradecanoylphorbol-13-acetate (TPA) skin tumor promotion susceptibility locus, Psl1, to distal chromosome 9 in crosses of sensitive DBA/2 mice with relatively resistant C57BL/6 mice. Here, we used the mouse two-stage skin carcinogenesis model to identify the gene(s) responsible for the effects of Psl1. METHODS Interval-specific congenic mouse strains (n ≥ 59 mice per strain) were used to more precisely map the Psl1 locus. Having identified glutathione S-transferase α4 (Gsta4) as a candidate tumor promotion susceptibility gene that mapped within the delimited region, we analyzed Gsta4-deficient mice (n = 62) for susceptibility to skin tumor promotion by TPA. We used quantitative polymerase chain reaction, western blotting, and immunohistochemistry to verify induction of Gsta4 in mouse epidermis following TPA treatment and biochemical assays to associate Gsta4 activity with tumor promotion susceptibility. In addition, single-nucleotide polymorphisms (SNPs) in GSTA4 were analyzed in a case-control study of 414 NMSC patients and 450 control subjects to examine their association with human NMSC. Statistical analyses of tumor studies in mice were one-sided, whereas all other statistical analyses were two-sided. RESULTS Analyses of congenic mice indicated that at least two loci, Psl1.1 and Psl1.2, map to distal chromosome 9 and confer susceptibility to skin tumor promotion by TPA. Gsta4 maps to Psl1.2 and was highly induced (mRNA and protein) in the epidermis of resistant C57BL/6 mice compared with that of sensitive DBA/2 mice following treatment with TPA. Gsta4 activity levels were also higher in the epidermis of C57BL/6 mice following treatment with TPA. Gsta4-deficient mice (C57BL/6.Gsta4(-/-) mice) were more sensitive to TPA skin tumor promotion (0.8 tumors per mouse vs 0.4 tumors per mouse in wild-type controls; difference = 0.4 tumors per mouse; 95% confidence interval = 0.1 to 0.7, P = .007). Furthermore, inheritance of polymorphisms in GSTA4 was associated with risk of human NMSC. Three SNPs were found to be independent predictors of NMSC risk. Two of these were associated with increased risk of NMSC (odds ratios [ORs] = 1.60 to 3.42), while the third was associated with decreased risk of NMSC (OR = 0.63). In addition, a fourth SNP was associated with decreased risk of basal cell carcinoma only (OR = 0.44). CONCLUSIONS Gsta4/GSTA4 is a novel susceptibility gene for NMSC that affects risk in both mice and humans.
Dissociation in Optokinetic Stimulation Sensitivity between Omission and Substitution Reading Errors in Neglect Dyslexia

Although omission and substitution errors in neglect dyslexia (ND) patients have always been considered as different manifestations of the same acquired reading disorder, recently, we proposed a new dual mechanism model. While omissions are related to the exploratory disorder which characterizes unilateral spatial neglect (USN), substitutions are due to a perceptual integration mechanism. A consequence of this hypothesis is that specific training for omission-type ND patients would aim at restoring the oculo-motor scanning and should not improve reading in substitution-type ND. With this aim we administered an optokinetic stimulation (OKS) to two brain-damaged patients with both USN and ND, MA and EP, who showed ND mainly characterized by omissions and substitutions, respectively. MA also showed an impairment in oculo-motor behavior with a non-reading task, while EP did not. The two patients presented a dissociation with respect to their sensitivity to OKS, so that, as expected, MA was positively affected, while EP was not. Our results confirm a dissociation between the two mechanisms underlying omission and substitution reading errors in ND patients. Moreover, they suggest that such a dissociation could possibly be extended to the effectiveness of rehabilitative procedures, and that patients who mainly omit contralesional-sided letters would benefit from OKS.
Coase Versus the Coasians

Who should enforce laws or contracts: judges or regulators? Many Coasians, though not Coase himself, advocate judicial enforcement. We show that the incentives facing judges and regulators crucially shape this choice. We then compare the regulation of financial markets in Poland and the Czech Republic in the 1990s. In Poland, strict enforcement of the securities law by a highly motivated regulator was associated with a rapidly developing stock market. In the Czech Republic, hands-off regulation was associated with a moribund stock market.
Quantum games and social norms. The quantum ultimatum game

The noncooperative Nash equilibrium solution of classical games corresponds to a rational expectations attitude on the part of the players. However, in many cases, games played by human players have outcomes very different from Nash equilibria. A restricted version of quantum games is proposed to implement, in mathematical games, the interplay of self-interest and internalized social norms that rules human behavior.
Maximum-likelihood estimation of migration rates and effective population numbers in two populations using a coalescent approach.

A new method for the estimation of migration rates and effective population sizes is described. It uses a maximum-likelihood framework based on coalescence theory. The parameters are estimated by Metropolis-Hastings importance sampling. In a two-population model this method estimates four parameters: the effective population size and the immigration rate for each population relative to the mutation rate. Summarizing over loci can be done by assuming either that the mutation rate is the same for all loci or that the mutation rates are gamma distributed among loci but the same for all sites of a locus. The estimates are as good as or better than those from an optimized FST-based measure. The program is available on the World Wide Web at http://evolution.genetics. washington.edu/lamarc.html/.
Optimal Public Policy for Venture Capital Backed Innovation

This Paper discusses the role of public policy towards the venture capital industry. The model emphasises four margins: supply of entrepreneurs due to career choice, entry of venture capital funds and search for investment opportunities, simultaneous entrepreneurial effort and managerial advice subject to double moral hazard, and mark-up pricing when the successful firm introduces a new good. The Paper derives an optimal policy that succeeds to implement a first best allocation in decentralized equilibrium. It also considers short- and long-run comparative static and welfare effects of piecemeal reform with regard to the capital gains tax, innovation subsidy, public R&D spending and other policy initiatives.
Bounding of MAP decode and forward relaying

We formulate the maximum a posteriori (MAP) rule for the decode-and-forward transmission strategy operating with a noisy relay. From the MAP rule we derive an analytical bound on the error probability, taking into account decoding errors at the relay. We further determine a practical close-to-MAP decoding scheme based on a convenient error model for the decoding operation at the relay. This error model allows for a trellis representation of the code described jointly by the encoding process at the source and the re-encoding process at the relay. Numerical results demonstrate a close agreement between our analytical results and monte carlo simulations.