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Geology of Mosquitia and Tela Basins, Honduras
Although the Mosquitia and Tela Basins are two of the better-explored sedimentary basins of Honduras, they are still underexplored compared with other basins in the general region. The Tela Basin is composed of three en echelon, narrow depocenters, resulting from extensional tectonics that initiated in the Oligocene. These depocenters were filled primarily by turbidite sedimentation that exceeds some 4,000 meters in thickness. The Mosquitia Basin is separated from the Tela Basin by a major regional, down-to-the-north, strike-slip fault. More than 75 percent of the basin lies in eastern Honduras, and the rest in Nicaragua. The basin's main depocenter is located near the Honduran-Nicaraguan border and is filled with some 9,000 meters of Upper Cretaceous and Tertiary sediments. Both the structural and stratigraphic framework of these two basins are intimately related to the evolution of the Chortis block as the block moved from its original position attached to southwestern Mexico to its present location as part of the Caribbean plate.
The Mosquitia Basin consists of three tectonic elements—the onshore Mosquitia Basin, the Mosquitia Platform, and the offshore Mosquitia Basin. Paleozoic strata are poorly understood in this region, but investigators have suggested that these rocks were affected by at least three episodes of deformation. The Chortis block was displaced into the present-day Caribbean during the Mesozoic, and displacement was followed by a suturing event as the Maya and Chortis blocks collided. This collision produced a regional compressional event, imparting a northwest structural grain and affecting both the onshore and offshore portions of the basin.Bureau of Economic Geolog
A Dual Stimuli Responsive Supramolecular Gel Provides Insulin Hydrolysis Protection and Redox-Controlled Release of Actives
Two supramolecular hydrogelators containing a central disulfide moiety and terminal carboxylic acid groups are studied. On the one hand, the hydrogels are responsive to a reductive environment, which transforms the disulfide unit to the corresponding thiols. On the other hand, the hydrogels show pH response associated with the presence of carboxylic acid units. Gels are formed at pH below ≈4 while at higher pH values, ionization of the gela-tors provokes gel disassembly. The properties of the gel are exploited for the release, as a proof of concept, of Bromophenol Blue in the presence of the reducing species tris(2-carboxyethyl)phosphine hydrochloride. Additionally, insulin is loaded into the hydrogels and protected from hydrolysis with simu-lated gastric fluid containing pepsin. Quantitative release of unaltered insulin, checked with an enzyme-linked immunosorbent assay colorimetric assay, is observed upon treatment with pH 7.4 buffer. This behavior would permit the use of the new hydrogels for oral insulin deliver
WHO ARE THE BULLS AND BEARS IN GLOBAL LODGING MARKETS?
This article looks at the values of market-based equities (common stocks) based on the relative investment valuation, analyzed with several earnings multiples in global lodging markets in 2014. To be specific, we compare the value of various common stock portfolios sorted for four geographical regions with those relative value investment metrics so that we can make a solid judgment about bullish and bearish markets demonstrating investors’ confidence or stagnancy, anomalies in prices indicating under and overvalued stocks, and outperforming lodging portfolios in global markets. Common stock prices in portfolios are standardized, utilizing earnings parameters such as Current Price/Earnings Ratio (PE) and its variants (Trailing and Forward PE), Price/Earnings to Growth (PEG), and The Market Value of Debt and Equity free of Cash-to-EBITDA (Value/EBITDA). Linking the relative value with earnings proxies and the stock portfolios, which are extracted in a homogeneous industry but are sorted from heterogeneous regions, primary findings of this study reveal that western and eastern markets have outperformed the Latin markets in regard to future earnings estimate, earnings growth, and excessive returns from the invested capital
Forecasting Forest Vulnerability to Drought in Pyrenean Silver Fir Forests Showing Dieback
Forest dieback is manifested as widespread loss of tree vigor, growth decline and high mortality rates. Forest dieback is becoming increasingly frequent and extended, particularly in drought-prone regions. This is the case of the south-western Spanish Pyrenees, where keystone species such as Silver fir reach their xeric and southern distribution limits. While dieback of this species has been widely documented in this area, we still lack methodologies to forecast the vulnerability of these forests in response to increasing drought stress so as to anticipate their potential dieback in the future. Here we study multiple features of Silver fir forests and trees to evaluate whether previous growth rates and their growth trends are valid predictors of forest dieback. Further, we validate our methodology revisiting two Silver fir sites sampled two decades ago. The defoliation degree was strongly related with radial growth, and growth trends differed between moderately to highly defoliated trees and non-defoliated trees. Forests showing dieback, i.e., those in which 25% of the sampled trees showed defoliation > 50%, were located at low elevation and received less rainfall in summer than forests showing no dieback. Trees showing high defoliation presented lower growth rates than non-defoliated trees. Moreover, we ratified that defoliation has increased considerably over the last two decades in one of the two revisited sites, but we were unable to accurately forecast growth trends in both sites, particularly in the site not showing dieback. The retrospective assessment of growth rates and trends offers valuable information on the vulnerability of Silver fir trees to drought. However, we are still far from being able to forecast the vulnerability of Silver fir forests to increasing drought. A systematic monitoring of growth across a wide tree-ring network of sites might provide valuable information to advance in this direction
Exploring pressure effects on metallic nanoparticles and surrounding media through plasmonic sensing
The sensing capabilities of gold nanorods under high-pressure conditions were investigated in methanol-ethanol mixtures (up to 13 GPa) and in water (up to 9 GPa) through their optical extinction. The longitudinal SPR band of AuNR exhibits a redshift with pressure which is the result of two main competing effects: compression of the conduction electrons which increases the bulk plasma frequency (blueshift) and increase in the solvent density (redshift). The variation in de SPR peak wavelength allows us to estimate the bulk modulus of the gold nanoparticles with a precision of 10 % and to obtain analytical functions providing the pressure dependence of the refractive index of water in three phases: liquid, ice VI and ice VII. Furthermore, the SPR band shows abrupt jumps at the liquid to ice phase VI and ice phase VII transitions, which are in accordance with the first-order character of these transitions.Financial support from Project PGC2018-101464-B-I00 (FEDER) and MALTA-Consolider Team (RED2018-102612-T) of the Ministerio de Ciencia, Innovación y Universidades is acknowledged
International Space Station USOS Potable Water Dispenser Development
The International Space Station (ISS) Russian Segment currently provides potable water dispensing capability for crewmember food and beverage rehydration. All ISS crewmembers rehydrate Russian and U.S. style food packages from this location. A new United States On-orbit Segment (USOS) Potable Water Dispenser (PWD) is under development. This unit will provide additional potable water dispensing capability to support an onorbit crew of six. The PWD is designed to provide incremental quantities of hot and ambient temperature potable water to U.S. style food packages. It will receive iodinated water from the Fuel Cell Water Bus in the U.S. Laboratory element. The unit will provide potable-quality water, including active removal of biocidal iodine prior to dispensing. A heater assembly contained within the unit will be able to supply up to 2.0 liters of hot water (65 to 93oC) every thirty minutes. This quantity will allow three to four crewmembers to rehydrate their food and beverages from this location during a single meal. The unit is designed to remain functional for up to ten years with replacement of limited life items such as filters. It will be the size of two stacked Shuttle Middeck lockers (approximately the size of two small suitcases) and integrated into a science payload rack in the U.S. Laboratory element. Providing potable-quality water at the proper temperature for food and beverage reconstitution is critical to maintaining crew health and well-being. The numerous engineering challenges as well as human factors and safety considerations during the concept, design, and prototyping are outlined in this paper
The “cushion effect” revisited:
Background: It is known the pattern and severity of injuries sustained during a motor vehicle accident depend on many variables. An interesting avenue for research is obesity as a positive or negative modifier for injury distribution patterns in MVA. We hypothesize that body mass index (BMI) will influence MVC related injury patterns.
Methods: We queried STRAC data for DHR - Edinburg for the years 2014 to 2018 using CPT codes for MVC/MVA, IS \u3e 8, age 15 - 64. Interactions between injury location, BMI, seatbelt and gender were analyzed.
Results: We had 191 detailed crashes, we found increasing age to be protective for abdomen and pelvis (OR .94), increasing BMI to be predisposing for extremity injuries (OR 1.06) and increasing BMI and female gender together to be protecting for head and neck injury (OR .98). Patient without abdominal injuries were younger with lower BMI. However sample size small (46).
Conclusion: BMI seems to have an exacerbating effect on extremity injuries and a protective effect for head and neck injuries driven predominantly by females. We believe this likely due to increase in momentum effect of each appendage and a decrease in torque of neck. Age seems to be a protective and we believe this is primarily due to hormonal deposition of adipose tissue. Overall it remains important to maintain a high index of suspicion when dealing with MVC triage patients and treat each individually
Brewster quasi bound states in the continuum in all-dielectric metasurfaces from single magnetic-dipole resonance meta-atoms
Bound states in the continuum (BICs) are ubiquitous in many areas of physics,
attracting especial interest for their ability to confine waves with infinite
lifetimes. Metasurfaces provide a suitable platform to realize them in
photonics; such BICs are remarkably robust, being however complex to tune in
frequency-wavevector space.Here we propose a scheme to engineer BICs and
quasi-BICs with single magnetic-dipole resonance meta-atoms. Upon changing the
orientation of the magnetic-dipole resonances, we show that the resulting
quasi-BICs,emerging from the symmetry-protected BIC at normal incidence, become
transparent for plane-wave illumination exactly at the magnetic-dipole angle,
due to a Brewster-like effect. While yielding infinite Q-factors at
normalincidence(canonical BIC), these are termed Brewster quasi-BICs since a
transmission channel is always allowed that slightly widens resonances at
oblique incidences. This is demonstrated experimentally through reflectance
measurements in the microwave regime with high-refractive-index mm-disk
metasurfaces. Such Brewster-inspired configuration is a plausible scenario to
achieve quasi-BICs throughout the electromagnetic spectrum inaccessible through
plane-wave illumination at given angles, which could be extrapolated to other
kind of waves.Comment: 15 pages, 7 figures; typos corrected, Figs. 3 & 5 modified, new Fig.
7 & references adde
Childhood sexual experiences with an older partner among men who have sex with men in Buenos Aires, Argentina
This study sought to describe childhood sexual experiences with older partners (CSEOP) among men who have sex with men (MSM) in Buenos Aires, Argentina. MSM were recruited through respondent driven sampling. They responded to a computer administered self-interview with questions on CSEOP, operationalized as manual, oral, genital, or anal contact prior to age 13 with a partner at least 4 years older. Of the 500 respondents, only 25% identified as gay. Eighteen percent of the respondents reported CSEOP, the majority of whom did not feel they were hurt by the experience and did not consider it to be childhood sexual abuse (CSA). Over two-thirds of MSM who reported CSEOP said that their older partner was a female. Only 4% of those with a female partner felt their experience was CSA compared to 44% of those who had a male partner. Among all men reporting CSEOP, those who felt sexually abused were more likely to have been physically forced or threatened, physically hurt, and emotionally hurt than those who did not feel sexually abused. Having CSEOP, being hurt by the experiences, and perceiving the experiences as sexual abuse were not associated with current HIV sexual risk or substance use behavior. In this sample of MSM in Argentina, a substantial minority reported CSEOP. Those who felt they had been sexually abused were much more likely to have had an older male partner than an older female partner, and were more likely to report having been physically forced and threatened by their older partner.Fil: Dolezal, Curtis. Columbia University; Estados UnidosFil: Carballo Diéguez, A.. Columbia University; Estados UnidosFil: Balán, Iván C.. Columbia University; Estados UnidosFil: Pando, María de los Ángeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; ArgentinaFil: Mabragaña, Marina. Columbia University; Estados UnidosFil: Marone, Ruben. Nexo Asociación Civil; ArgentinaFil: Barreda, Victoria. Nexo Asociación Civil; ArgentinaFil: Ávila, María Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentin
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