The Impact of Universal Service Obligations and Other External and Cross Subsidies on Teledensity in Developing Countries

The failure to consider the complexity of the regional telecommunication systems in planning has increased the telecom gap between other regions and the rural sectors in the developing countries. Earmarked funds generated by Universal Service Obligations and various types of other direct and cross-subsidies have not helped this situation. This research uses system dynamics modeling approach to understand the complexity of the system and to evaluate how different policies affect telephone densities. It is demonstrated that some of the prevalent policies may be counterproductive. Policy experiments with the model demonstrate that market-clearing pricing implemented with Universal Service Obligations, and a value-added service combination may significantly improve rural telecommunications

EVALUACIÓN POSNATAL DE LAS ARTERIOLAS PULMONARES EN CRÍAS DE ALPACA

In the postnatal phase in mammalians, the vasodilatation of the pulmonary arterioles is critical, since this will affect the amount of blood passing through the alveoli for oxygenation. The aim of the study was to evaluate the diameter, the thickness of the muscle layer and the relationship muscle layer/arteriolar diameter (CM/DA) as indication of changes in the vascular lumen in the postnatal period of baby alpacas. Lungs of 36 alpacas between 1 to 45 days of age were obtained according to nine age groups (one group each 5 days of age). The lung histological sections were stained with Mallory’s phosphotungstic acid hematoxylin. The arteriolar diameter showed a significant increase (p<0.05) between age groups 1 and 2 versus 7, 8 and 9. The thickness of the muscle layer showed no significant changes between groups, while the CM/DA relationship values decreased with age (groups 1 and 2 were statistical different of groups 6, 7, 8 and 9; p<0.05). It is concluded that the CM/DA relationship decreases and the lumen of pulmonary arterioles increases according to age, and this is due to increased arteriolar diameter (p<0.05) but not to thickness of smooth muscles.En la etapa posnatal de mamíferos es de vital importancia la vasodilatación de las arteriolas pulmonares, pues de estas dependerá la cantidad de sangre que pase por los alveolos para ser oxigenada. El presente estudio tuvo por objetivo evaluar el diámetro, el grosor de la capa muscular y la relación capa muscular/diámetro arteriolar (CM/DA) para evaluar los cambios de la luz vascular en la etapa posnatal de crías de alpaca. Se utilizaron pulmones de 36 alpacas de 1 a 45 días de edad, distribuidos en nueve grupos etarios (un grupo por cada cinco días de edad). Los cortes histológicos de pulmón fueron coloreados con hematoxilina fosfotúngstica de Mallory. El diámetro arteriolar pulmonar mostró un incremento significativo (p<0.05) entre los grupos etarios 1 y 2 versus 7, 8 y 9. El grosor de la capa muscular no evidenció cambios significativos entre grupos, mientras que los valores de la relación CM/DA se incrementaron con la edad, habiendo diferencias estadísticas entre grupos etarios 1 y 2 versus 6, 7, 8 y 9 (p<0.05). Se concluye que la relación CM/DA disminuye y el lumen de las arteriolas pulmonares aumenta a medida que la edad de los animales se incrementa, debido al aumento del diámetro arteriolar pulmonar (p<0.05), mas no del grosor del músculo liso

Cataclysmic Variables from Sloan Digital Sky Survey V -- the search for period bouncers continues

SDSS-V is carrying out a dedicated survey for white dwarfs, single and in binaries, and we report the analysis of the spectroscopy of cataclysmic variables (CVs) and CV candidates obtained during the final plug plate observations of SDSS. We identify eight new CVs, spectroscopically confirm 53 and refute eleven published CV candidates, and we report 21 new or improved orbital periods. Combined with previously published data, the orbital period distribution of the SDSS-V CVs does not clearly exhibit a period gap. This is consistent with previous findings that spectroscopically identified CVs have a larger proportion of short-period systems compared to samples identified from photometric variability. Remarkably, despite a systematic search, we find very few period bouncers. We estimate the space density of period bouncers to be $\simeq0.2\times10^{-6}\,\mathrm{pc}^{-3}$, i.e. they represent only a few per cent of the total CV population. This suggests that during their final phase of evolution, CVs either destroy the donor, e.g. via a merger, or that they become detached and cease mass transfer.Comment: Submitted to MNRA

Permafrost is warming at a global scale

Permafrost warming has the potential to amplify global climate change, because when frozen sediments thaw it unlocks soil organic carbon. Yet to date, no globally consistent assessment of permafrost temperature change has been compiled. Here we use a global data set of permafrost temperature time series from the Global Terrestrial Network for Permafrost to evaluate temperature change across permafrost regions for the period since the International Polar Year (2007-2009). During the reference decade between 2007 and 2016, ground temperature near the depth of zero annual amplitude in the continuous permafrost zone increased by 0.39 ± 0.15 °C. Over the same period, discontinuous permafrost warmed by 0.20 ± 0.10 °C. Permafrost in mountains warmed by 0.19 ± 0.05 °C and in Antarctica by 0.37 ± 0.10 °C. Globally, permafrost temperature increased by 0.29 ± 0.12 °C. The observed trend follows the Arctic amplification of air temperature increase in the Northern Hemisphere. In the discontinuous zone, however, ground warming occurred due to increased snow thickness while air temperature remained statistically unchanged

Hostile Takeover by Plasmodium: Reorganization of Parasite and Host Cell Membranes during Liver Stage Egress

The protozoan parasite Plasmodium is transmitted by female Anopheles mosquitoes and undergoes obligatory development within a parasitophorous vacuole in hepatocytes before it is released into the bloodstream. The transition to the blood stage was previously shown to involve the packaging of exoerythrocytic merozoites into membrane-surrounded vesicles, called merosomes, which are delivered directly into liver sinusoids. However, it was unclear whether the membrane of these merosomes was derived from the parasite membrane, the parasitophorous vacuole membrane or the host cell membrane. This knowledge is required to determine how phagocytes will be directed against merosomes. Here, we fluorescently label the candidate membranes and use live cell imaging to show that the merosome membrane derives from the host cell membrane. We also demonstrate that proteins in the host cell membrane are lost during merozoite liberation from the parasitophorous vacuole. Immediately after the breakdown of the parasitophorous vacuole membrane, the host cell mitochondria begin to degenerate and protein biosynthesis arrests. The intact host cell plasma membrane surrounding merosomes allows Plasmodium to mask itself from the host immune system and bypass the numerous Kupffer cells on its way into the bloodstream. This represents an effective strategy for evading host defenses before establishing a blood stage infection

dTip60 HAT Activity Controls Synaptic Bouton Expansion at the Drosophila Neuromuscular Junction

Background: Histone acetylation of chromatin plays a key role in promoting the dynamic transcriptional responses in neurons that influence the neuroplasticity linked to cognitive ability, yet the specific histone acetyltransferases (HATs) that create such epigenetic marks remain to be elucidated. Methods and Findings: Here we use the Drosophila neuromuscular junction (NMJ) as a well-characterized synapse model to identify HATs that control synaptic remodeling and structure. We show that the HAT dTip60 is concentrated both pre and post-synaptically within the NMJ. Presynaptic targeted reduction of dTip60 HAT activity causes a significant increase in synaptic bouton number that specifically affects type Is boutons. The excess boutons show a suppression of the active zone synaptic function marker bruchpilot, suggesting defects in neurotransmission function. Analysis of microtubule organization within these excess boutons using immunohistochemical staining to the microtubule associated protein futsch reveals a significant increase in the rearrangement of microtubule loop architecture that is required for bouton division. Moreover, a-tubulin acetylation levels of microtubules specifically extending into the terminal synaptic boutons are reduced in response to dTip60 HAT reduction. Conclusions: Our results are the first to demonstrate a causative role for the HAT dTip60 in the control of synaptic plasticity that is achieved, at least in part, via regulation of the synaptic microtubule cytoskeleton. These findings have implication

Inner/Outer Nuclear Membrane Fusion in Nuclear Pore Assembly: Biochemical Demonstration and Molecular Analysis

The nuclear pore complex (NPC) is characterized by a long-lived membrane-lined channel connecting the inner and outer nuclear membranes. This stabilized membrane channel, within which the nuclear pore is built, has little evolutionary precedent. In this report we demonstrate and map the inner/outer nuclear membrane fusion in NPC assembly

Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe

Severe Asthma Standard-of-Care Background Medication Reduction With Benralizumab: ANDHI in Practice Substudy

Background: The phase IIIb, randomized, parallel-group, placebo-controlled ANDHI double-blind (DB) study extended understanding of the efficacy of benralizumab for patients with severe eosinophilic asthma. Patients from ANDHI DB could join the 56-week ANDHI in Practice (IP) single-arm, open-label extension substudy. Objective: Assess potential for standard-of-care background medication reductions while maintaining asthma control with benralizumab. Methods: Following ANDHI DB completion, eligible adults were enrolled in ANDHI IP. After an 8-week run-in with benralizumab, there were 5 visits to potentially reduce background asthma medications for patients achieving and maintaining protocol-defined asthma control with benralizumab. Main outcome measures for non-oral corticosteroid (OCS)-dependent patients were the proportions with at least 1 background medication reduction (ie, lower inhaled corticosteroid dose, background medication discontinuation) and the number of adapted Global Initiative for Asthma (GINA) step reductions at end of treatment (EOT). Main outcomes for OCS-dependent patients were reductions in daily OCS dosage and proportion achieving OCS dosage of 5 mg or lower at EOT. Results: For non-OCS-dependent patients, 53.3% (n = 208 of 390) achieved at least 1 background medication reduction, increasing to 72.6% (n = 130 of 179) for patients who maintained protocol-defined asthma control at EOT. A total of 41.9% (n = 163 of 389) achieved at least 1 adapted GINA step reduction, increasing to 61.8% (n = 110 of 178) for patients with protocol-defined EOT asthma control. At ANDHI IP baseline, OCS dosages were 5 mg or lower for 40.4% (n = 40 of 99) of OCS-dependent patients. Of OCS-dependent patients, 50.5% (n = 50 of 99) eliminated OCS and 74.7% (n = 74 of 99) achieved dosages of 5 mg or lower at EOT. Conclusions: These findings demonstrate benralizumab's ability to improve asthma control, thereby allowing background medication reduction

Energy dependence of ϕ meson production at forward rapidity in pp collisions at the LHC

The production of $\phi$ mesons has been studied in pp collisions at LHC energies with the ALICE detector via the dimuon decay channel in the rapidity region $2.5< y < 4$. Measurements of the differential cross section $\mathrm{d}^2\sigma /\mathrm{d}y \mathrm{d}p_{\mathrm {T}}$ are presented as a function of the transverse momentum ($p_{\mathrm {T}}$) at the center-of-mass energies $\sqrt{s}=5.02$, 8 and 13 TeV and compared with the ALICE results at midrapidity. The differential cross sections at $\sqrt{s}=5.02$ and 13 TeV are also studied in several rapidity intervals as a function of $p_{\mathrm {T}}$, and as a function of rapidity in three $p_{\mathrm {T}}$ intervals. A hardening of the $p_{\mathrm {T}}$-differential cross section with the collision energy is observed, while, for a given energy, $p_{\mathrm {T}}$ spectra soften with increasing rapidity and, conversely, rapidity distributions get slightly narrower at increasing $p_{\mathrm {T}}$. The new results, complementing the published measurements at $\sqrt{s}=2.76$ and 7 TeV, allow one to establish the energy dependence of $\phi$ meson production and to compare the measured cross sections with phenomenological models. None of the considered models manages to describe the evolution of the cross section with $p_{\mathrm {T}}$ and rapidity at all the energies.publishedVersio