Energy Efficiency of Hybrid-Power HetNets: A Population-like Games Approach

In this paper, a distributed control scheme based on population games is proposed. The controller is in charge of dealing with the energy consumption problem in a Heterogeneous Cellular Network (HetNet) powered by hybrid energy sources (grid and renewable energy) while guaranteeing appropriate quality of service (QoS) level at the same time. Unlike the conventional approach in population games, it considers both atomicity and non-anonymity. Simulation results show that the proposed population-games approach reduces grid consumption by up to about 12% compared to the traditional best-signal level association policy.U.S. Air Force Office of Scientific Research FA9550-17-1-0259Ministerio de Cultura y Deporte DPI2016-76493-C3-3-RMinisterio de Economía y Empresa DPI2017-86918-

A Coalitional Model Predictive Control Approach for Heterogeneous Cellular Networks

Heterogeneous cellular networks (HetNets) are large-scale systems that comprise numerous base stations interacting with a significant number of users of diverse types. Finding a trade-off between energy consumption and quality of service is one of the major challenges in these networks. To deal with this issue, a coalitional model predictive control (MPC) approach is proposed for a HetNet powered by renewable power sources, and compared in simulation with the traditional best-signal level mechanism and the centralized MPC method. Furthermore, other key performance indicators associated with grid consumption such as the number of served users and transmission rates are also evaluated

Bronchoscopic balloon dilatation in the management of bronchial stenosis following lung transplantation

SummaryBackgroundBronchial stenosis (BS) is currently found in 7–15% of lung transplantation (LT) recipients. Current treatment strategies have included Nd:Yag laser, cryotherapy, bougie dilatation and stent placement. Bronchoscopic balloon dilatation has been used as alternative treatment in a few cases with controversial results. This is a study to prospectively assess the efficacy of bronchoscopic balloon dilatation as a first step in the management of post-LT BS.MethodsFrom January 1995 to December 2002, bronchoscopic balloon dilatation was evaluated as first therapeutic option in all consecutive LT patients with BS. Symptoms, pulmonary function tests, airway diameter and use of other therapeutic techniques were evaluated.ResultsA total of 10 out of 284 anastomed airways (3.5%) in 9 out of 152 LT patients were included in the study and follow-up lasted from 6 to 81 months. Dilatation of all but one BS met with initial success: increase of both luminal dimensions and forced vital capacity (P=0.01), and relief of symptoms. Bronchoscopic balloon dilatation long-term follow-up showed effective results in 5 out of 10 (50%) bronchial stenoses, after an average of 4 bronchoscopic balloon dilatation procedures (range 1–8). No severe complications were observed. Stent placement was required in the other 5 bronchial stenoses.ConclusionsBronchoscopic balloon dilatation is a safe method that should be considered as first therapeutic treatment of post-LT BS. Its use avoids the need for stent placement in up to 50% of cases

Building capacity for dementia care in Latin America and the Caribbean

Latin America and the Caribbean (LAC) have limited facilities and professionals trained to diagnose, treat, and support people with dementia and other forms of cognitive impairment. The situation for people with dementia is poor, and worsening as the proportion of elderly in the general population is rapidly expanding. We reviewed existing initiatives and provided examples of actions taken to build capacity and improve the effectiveness of individuals, organizations, and national systems that provide treatment and support for people with dementia and their caregivers. Regional barriers to capacity building and the importance of public engagement are highlighted. Existing programs need to disseminate their objectives, accomplishments, limitations, and overall lessons learned in order to gain greater recognition of the need for capacity-building programs

Ophthalmic Manifestations of Congenital Zika Syndrome in Colombia and Venezuela

IMPORTANCE The ocular manifestations and sequelae of Zika virus infection are not well known. Recently, the World Health Organization changed the declaration of Zika as a public health emergency and designated the viral outbreak and related microcephaly clusters as a long-term program of work. This change indicates the urgent need to evaluate and document ophthalmic manifestations in patients for timely management of this disease. In addition, confirmation whether the public health problem in Brazil extends to other regions in South America is needed. OBJECTIVE To report the ocular manifestations of congenital Zika syndrome with microcephaly in Colombia and Venezuela. DESIGN, SETTING, AND PARTICIPANTS This prospective case series included 43 patients from 2 ophthalmic centers in Colombia and Venezuela who underwent evaluation from October 1, 2015, through June 30, 2016, and were clinically diagnosed with congenital Zika syndrome. Twenty patients were Hispanic; 13, African; 8, white; and 2, Native American. INTERVENTIONS Ophthalmic and systemic evaluations and serologic testing were performed on all infants. Patients underwent external ocular examination and dilated ophthalmoscopy. Serologic testing ruled out toxoplasmosis, rubella, cytomegalovirus, syphilis, and human immunodeficiency virus. MAIN OUTCOMES AND MEASURES Ophthalmic manifestations of congenital Zika syndrome. RESULTS Of the 43 patients included in this series (28 female and 15 male), the mean (SD) age at examination was 2.1 (1.5) months. The mothers of all the children had no ophthalmic findings and did not report ocular symptoms during pregnancy. All patients had bilateral ophthalmic manifestations. Optic nerve findings included hypoplasia with the double-ring sign, pallor, and increased cup-disc ratio in 5 patients (11.6%). Macular abnormalities included mild to severe pigment mottling in 27 patients (63%) and lacunar maculopathy in 3 (6.9%). Chorioretinal scarring was present in 3 patients (7%). Eleven patients (26%) had a combination of lesions in the posterior pole. Five patients (12%) were diagnosed with congenital glaucoma, characterized by the clinical triad of epiphora, photophobia, and blepharospasm; increased intraocular pressure; corneal clouding at birth; and buphthalmos. These data reveal that 12%(95%CI, 5%-24%) of cases of congenital Zika with microcephaly had anterior segment abnormalities and 88%(95%CI, 76%-94%) had important macular and optic nerve abnormalities. The visual sequelae of these ophthalmic manifestations remain unknown. CONCLUSIONS AND RELEVANCE Congenital Zika syndrome in the current study had severe ocular abnormalities, and all patients had bilateral involvement. Ocular findings were focal macular pigment mottling, chorioretinal atrophy with a predilection for the macular area, congenital glaucoma and optical nerve hypoplasia, and optic disc abnormalities. Ophthalmic examination is recommended in patients with congenital Zika syndrome

Photochromic mechanism in oxygen-containing yttrium hydride thin films: An optical perspective

Oxygen-containing yttrium hydride thin films exhibit photochromic behavior: Transparent thin films reversibly switch from a transparent state to a photodarkened state after being illuminated with UV or blue light. From optical spectrophotometry and ellipsometry measurements of the transparent state and photodarkened state, it is concluded that the photochromic effect can be explained by the gradual growth, under illumination, of metallic domains within the initial wide-band-gap semiconducting lattice. This conclusion is supported by Raman measurements

Risk of Dementia Associated with Elevated Plasma Homocysteine in a Latin American Population

The relationship between total homocysteine (tHcy) and dementia risk remains controversial, as the association varies among populations and dementia subtypes. We studied a Venezuelan population that has high prevalence of both elevated tHcy and dementia. We tested the hypotheses that (1) elevated tHcy is associated with increased dementia risk, (2) the risk is greater for vascular dementia (VaD) than for Alzheimer's disease (AD), and (3) a history of stroke may partly explain this association. 2100 participants (≥55 years old) of the Maracaibo Aging Study underwent standardized neurological, neuropsychiatric, and cardiovascular assessments. Elevated tHcy was significantly associated with dementia, primarily VaD. When history of stroke and other confounding factors were taken into account, elevated tHcy remained a significant risk factor in older (>66 years), but not in younger (55–66 years) subjects. Ongoing studies of this population may provide insight into the mechanism by which tHcy increases risk for dementia