Future CMB tests of dark matter: ultra-light axions and massive neutrinos

Measurements of cosmic microwave background (CMB) anisotropies provide strong evidence for the existence of dark matter and dark energy. They can also test its composition, probing the energy density and particle mass of different dark-matter and dark-energy components. CMB data have already shown that ultra-light axions (ULAs) with mass in the range $10^{-32}~{\rm eV} \to 10^{-26}~{\rm eV}$ compose a fraction $< 0.01$ of the cosmological critical density. Here, the sensitivity of a proposed CMB-Stage IV (CMB-S4) experiment (assuming a 1 arcmin beam and $< 1~\mu K{\rm-arcmin}$ noise levels over a sky fraction of 0.4) to the density of ULAs and other dark-sector components is assessed. CMB-S4 data should be $\sim 10$ times more sensitive to the ULA energy-density than Planck data alone, across a wide range of ULA masses $10^{-32}< m_{a}< 10^{-23}~{\rm eV}$, and will probe axion decay constants of $f_{a}\approx 10^{16}~{\rm GeV}$, at the grand unified scale. CMB-S4 could improve the CMB lower bound on the ULA mass from $\sim 10^{-25}~{\rm eV}$ to $10^{-23}~{\rm eV}$, nearing the mass range probed by dwarf galaxy abundances and dark-matter halo density profiles. These improvements will allow for a multi-$\sigma$ detection of percent-level departures from CDM over a wide range of masses. Much of this improvement is driven by the effects of weak gravitational lensing on the CMB, which breaks degeneracies between ULAs and neutrinos. We also find that the addition of ULA parameters does not significantly degrade the sensitivity of the CMB to neutrino masses. These results were obtained using the axionCAMB code (a modification to the CAMB Boltzmann code), presented here for public use.Comment: 16 pages, 12 figures. The axionCAMB code will be available online at http://github.com/dgrin1/axionCAMB from 1 August 201

El impacto del seguro de vida colectivo de saldo deudor en las entidades financieras de la República Argentina

El seguro de vida colectivo de saldo deudor es un producto que millones de clientes de entidades financieras de la Argentina poseen y cuyo alcance pocos conocen. Esto es debido a su carácter de obligatorio en determinados productos como: tarjeta de crédito, préstamos personales, hipotecarios, prendarios y cuenta corriente. Si bien es un producto “impuesto”, no implica que sea abusivo para el cliente. Por el contrario, es beneficioso tanto para él como para los otros intervinientes. Para el cliente deudor, dado que no deja a sus herederos con la carga de las deudas en el caso de muerte y en el caso de la entidad financiera, tiene el beneficio de poder recuperar la deuda contraída por el cliente fallecido. Finalmente, para la compañía de seguros, como es la prestadora del servicio, se traduce en la ganancia por la venta del producto, entre otras variables que se verán en el presente trabajo. El equilibrio planteado en el párrafo anterior referente a los beneficios, se desarticula al registrarse importantes pérdidas monetarias en las entidades financieras. Estas son originadas por la falta de cobro de los siniestros que se motivaron en los fallecimientos de los clientes deudores. En el presente trabajo se investigaron l as razones de estas pérdidas y para ello, se realizaron entrevistas a responsables del proceso del producto Seguros en las entidades financieras. También se estudió el impacto que se produce en el mercado cuando una entidad pertenece al mismo grupo económico que una aseguradora , y por último se analizaron todos los aspectos normativos de las leyes y resoluciones vigentes. Se concluye que para dar solución a este problema, las entidades financieras deberán modificar sus procesos operativos, específicamente en el control de la supervivencia del cliente deudor. Asimismo, se arriba a la conclusión de que las entidades y compañías de seguros que comparten el mismo grupo económico, cuentan con una ventaja competitiva. Cabe destacar que la normativa vigente no especifica el procedimiento en los casos de siniestros para este seguro

Characterization of a Mycobacterium smegmatis uvrA mutant impaired in dormancy induced by hypoxia and low carbon concentration

<p>Abstract</p> <p>Background</p> <p>The aerobic fast-growing <it>Mycobacterium smegmatis</it>, like its slow-growing pathogenic counterpart Mycobacterium tuberculosis, has the ability to adapt to microaerobiosis by shifting from growth to a non-proliferating or dormant state. The molecular mechanism of dormancy is not fully understood and various hypotheses have been formulated to explain it. In this work, we open new insight in the knowledge of <it>M. smegmatis </it>dormancy, by identifying and characterizing genes involved in this behavior.</p> <p>Results</p> <p>In a library generated by transposon mutagenesis, we searched for <it>M. smegmatis </it>mutants unable to survive a coincident condition of hypoxia and low carbon content, two stress factors supposedly encountered in the host and inducing dormancy in tubercle bacilli. Two mutants were identified that mapped in the <it>uvrA </it>gene, coding for an essential component of the Nucleotide Excision Repair system (NER). The two mutants showed identical phenotypes, although the respective transposon insertions hit different regions of the <it>uvrA </it>gene. The restoration of the <it>uvrA </it>activity in <it>M. smegmatis </it>by complementation with the <it>uvrA </it>gene of <it>M. tuberculosis</it>, confirmed that i) <it>uvrA </it>inactivation was indeed responsible for the inability of <it>M. smegmatis </it>cells to enter or exit dormancy and, therefore, survive hypoxia and presence of low carbon and ii) showed that the respective <it>uvrA </it>genes of <it>M. tuberculosis </it>and <it>M. smegmatis </it>are true orthologs. The rate of survival of wild type, <it>uvrA </it>mutant and complemented strains under conditions of oxidative stress and UV irradiation was determined qualitatively and quantitatively.</p> <p>Conclusions</p> <p>Taken together our results confirm that the mycobacterial NER system is involved in adaptation to various stress conditions and suggest that cells with a compromised DNA repair system have an impaired dormancy behavior.</p

Synthesis of Silver Nanoparticles by a Bryophilous Rhizoctonia species

We demonstrate the synthesis of silver nanoparticles by a potentially benign species of bryophilous Rhizoctonia in two different media. The first medium supports fungal growth and the up‐regulation of nitrate reductase, while the second medium supports fungal growth and the repression of nitrate reductase. For both media, the resulting silver nanoparticles were ca. 25‐50nm and were subglobose to broadly ellipsoidal in shape. The optical analysis of the silver nanoparticles from both media demonstrated plasmon resonance at 415nm, confirming their metallic properties. The liquid colour change typically observed for extracellular silver nanoparticle formation was absent in both media. The silver nanoparticles in the two different media displayed different chemical associations; fewer associated chemicals were found with the media, which supported the up‐regulation of nitrate reductase. Another difference included plate‐like silver nanoparticle conglomerations, which were only encountered on hyphae from the medium that repressed nitrate reductase. There was also a noticeable difference in the capping agent formations between each media. The Rhizoctonia isolate examined in this study is suitable for large‐scale industrial applications because it does not produce spores and would have minimal impact on air quality

Entanglement vs. gap for one-dimensional spin systems

We study the relationship between entanglement and spectral gap for local Hamiltonians in one dimension. The area law for a one-dimensional system states that for the ground state, the entanglement of any interval is upper-bounded by a constant independent of the size of the interval. However, the possible dependence of the upper bound on the spectral gap Delta is not known, as the best known general upper bound is asymptotically much larger than the largest possible entropy of any model system previously constructed for small Delta. To help resolve this asymptotic behavior, we construct a family of one-dimensional local systems for which some intervals have entanglement entropy which is polynomial in 1/Delta, whereas previously studied systems, such as free fermion systems or systems described by conformal field theory, had the entropy of all intervals bounded by a constant times log(1/Delta).Comment: 16 pages. v2 is final published version with slight clarification

Spin chirality on a two-dimensional frustrated lattice

The collective behavior of interacting magnetic moments can be strongly influenced by the topology of the underlying lattice. In geometrically frustrated spin systems, interesting chiral correlations may develop that are related to the spin arrangement on triangular plaquettes. We report a study of the spin chirality on a two-dimensional geometrically frustrated lattice. Our new chemical synthesis methods allow us to produce large single crystal samples of KFe3(OH)6(SO4)2, an ideal Kagome lattice antiferromagnet. Combined thermodynamic and neutron scattering measurements reveal that the phase transition to the ordered ground-state is unusual. At low temperatures, application of a magnetic field induces a transition between states with different non-trivial spin-textures.Comment: 7 pages, 4 figure

Exact multilocal renormalization on the effective action : application to the random sine Gordon model statics and non-equilibrium dynamics

We extend the exact multilocal renormalization group (RG) method to study the flow of the effective action functional. This important physical quantity satisfies an exact RG equation which is then expanded in multilocal components. Integrating the nonlocal parts yields a closed exact RG equation for the local part, to a given order in the local part. The method is illustrated on the O(N) model by straightforwardly recovering the $\eta$ exponent and scaling functions. Then it is applied to study the glass phase of the Cardy-Ostlund, random phase sine Gordon model near the glass transition temperature. The static correlations and equilibrium dynamical exponent $z$ are recovered and several new results are obtained. The equilibrium two-point scaling functions are obtained. The nonequilibrium, finite momentum, two-time $t,t'$ response and correlations are computed. They are shown to exhibit scaling forms, characterized by novel exponents $\lambda_R \neq \lambda_C$, as well as universal scaling functions that we compute. The fluctuation dissipation ratio is found to be non trivial and of the form $X(q^z (t-t'), t/t')$. Analogies and differences with pure critical models are discussed.Comment: 33 pages, RevTe

Enhancing identification and treatment of patients with concomitant chronic venous insufficiency and diabetes mellitus A modified Delphi study from the CODAC (ChrOnic venous disease and Diabetes Advisory Council) group

Background: Chronic venous insufficiency (CVI) and diabetes mellitus (DM) pose significant burdens to patients and healthcare systems. While the two diseases share a number of commonalities in risk factors and pathophysiology, they are often assessed and managed separately. This can lead to a worsening of comorbidities and limitations in a patient’s quality of life. This project aims to develop recommendations to enhance the identification and treatment of patients with concomitant CVI and DM. Methods: Using a modified Delphi method, a panel of experts developed 38 Likert Scale and two multiple choice questions across six key themes. These were used to form an online survey which was disseminated through a convenience sampling approach to CVI and DM healthcare professionals across Europe, Central America, South America, and the Middle East. The threshold for consensus was set at ≥75%.Results: A total of 238 responses were received. 27/38 statements attained &gt;90% agreement, nine of 38 attained between 75-90%, and two failed to meet the threshold (&lt;75%). The awareness around the impact of the two diseases was high, but a gap was highlighted in the identification of patients with concomitant CVI and DM. Conclusions: The high level of agreement shows that healthcare professionals are aware of the gaps in identification and treatment of patients with concomitant CVI and DM, and of the need to approach this as a combined therapy area. An algorithm is proposed to help the identification of at-risk patients and to provide recommendations on the management of patients with concomitant disease. (Cite this article as: Bozkurt AK, van Rijn MJ, Bouskela E, Gastaldi G, Glauser F, Haller H, et al. Enhancing identification and treatment of patients with concomitant chronic venous insufficiency and diabetes mellitus. A modified Delphi study from the CODAC (ChrOnic venous disease and Diabetes Advisory Council) group. Int Angiol 2023;42:427-35. DOI: 10.23736/S0392-9590.23.05061-7)</p

Investigating the structural compaction of biomolecules upon transition to the gas-phase using ESI-TWIMS-MS

Collision cross-section (CCS) measurements obtained from ion mobility spectrometry-mass spectrometry (IMS-MS) analyses often provide useful information concerning a protein’s size and shape and can be complemented by modeling procedures. However, there have been some concerns about the extent to which certain proteins maintain a native-like conformation during the gas-phase analysis, especially proteins with dynamic or extended regions. Here we have measured the CCSs of a range of biomolecules including non-globular proteins and RNAs of different sequence, size, and stability. Using traveling wave IMS-MS, we show that for the proteins studied, the measured CCS deviates significantly from predicted CCS values based upon currently available structures. The results presented indicate that these proteins collapse to different extents varying on their elongated structures upon transition into the gas-phase. Comparing two RNAs of similar mass but different solution structures, we show that these biomolecules may also be susceptible to gas-phase compaction. Together, the results suggest that caution is needed when predicting structural models based on CCS data for RNAs as well as proteins with non-globular folds