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The Colorado Plateau Coring Project (CPCP): 100 Million Years of Earth System History
Lasting over 100 million years, the early Mesozoic (252 to 145 Ma) is punctuated by two of the five major mass extinctions of the Phanerozoic (Permo-Triassic and Triassic-Jurassic) plus several smaller extinction events. It witnessed the evolutionary appearance of the modem terrestrial biota including frogs, salamanders, turtles, lizards, crocodilians, dinosaurs, birds, and mammals, and spans a time of dramatic climate changes on the continents. What is arguably the richest record of these events lies in the vast (- 2.5 million km2) complex of epicontinental basins in the western part of Pangea, now largely preserved on the Colorado Plateau (Fig.l). Since the mid-19th century, classic studies of these basins, their strata, and their fossils have made this succession instrumental in framing our context of the early Mesozoic Earth system as reflected in the international literature. Despite this long and distinguished history of study of the Colorado Plateau region, striking ambiguities in temporal resolution, major uncertainties in global correlations, and significant doubts about paleolatitudinal position hamper incorporation of the huge amount of information from the region into-tests of major competing climatic, biotic, and tectonic hypotheses and a fundamental understanding of Earth system processes
Bacterias marinas antagonistas de Staphylococcus aureus y Vibrio parahaemolyticus, agentes de enfermedades trasmitidas por alimentos.
Este estudio tuvo como objetivo la identificación de microorganismos marinos de las costas mexicanas que presentenactividad antimicrobiana contra Staphylococcus aureus y Vibrio parahaemolyticus, conocidos en el ámbito mundial por ser agentes de intoxicación alimentaria. Se colectaron muestras representativas de algas, sedimentos salinos, crustáceos y moluscos. De las 42 cepas probadas, 15 inhibieron estos patógenos. La secuenciación del gen 16S rRNA identificó solo cepas de Bacillus. Las cepas con la actividad inhibidora más alta contra S. aureus fueron B. aerius y B. pumilus. Las cepas B. pumilus, B. altitudinis y B. oryzicola mostraron una mayor actividad antimicrobiana contra V. parahaemolyticus. Este es el primer estudio del aislamiento de B. aerius, B. oryzicola, B. safensis, B. boroniphilus y B. altitudinis de ecosistemas marinos en México, así como el primer estudio que reporta sus efectos inhibidores contra S. aureus y V. parahaemolyticus. Los compuestos activos de los antagonistas se están identificando y evaluando actualmente. Los ecosistemas marinos tienen la mayor diversidad bacteriana asociada con invertebrados y algas; sin embargo, esta diversidad bacteriana no ha sido bien
estudiada en las costas mexicanas
Antiviral mode of action of bovine dialyzable leukocyte extract against human immunodeficiency virus type 1 infection
<p>Abstract</p> <p>Background</p> <p>Bovine dialyzable leukocyte extract (bDLE) is derived from immune leukocytes obtained from bovine spleen. DLE has demonstrated to reduce transcription of Human Immunodeficiency Virus Type 1 (HIV-1) and inactivate the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway. Therefore, we decided to clarify the mode of antiviral action of bDLE on the inhibition of HIV-1 infection through a panel of antiviral assays.</p> <p>Results</p> <p>The cytotoxicity, HIV-1 inhibition activity, residual infectivity of bDLE in HIV-1, time of addition experiments, fusion inhibition of bDLE for fusogenic cells and the duration of cell protection even after the removal of bDLE were all assessed in order to discover more about the mode of the antiviral action.</p> <p>HIV-1 infectivity was inhibited by bDLE at doses that were not cytotoxic for HeLa-CD4-LTR-β-gal cells. Pretreatment of HIV-1 with bDLE did not decrease the infectivity of these viral particles. Cell-based fusion assays helped to determine if bDLE could inhibit fusion of Env cells against CD4 cells by membrane fusion and this cell-based fusion was inhibited only when CD4 cells were treated with bDLE. Infection was inhibited in 80% compared with the positive (without EDL) at all viral life cycle stages in the time of addition experiments when bDLE was added at different time points. Finally, a cell-protection assay against HIV-1 infection by bDLE was performed after treating host cells with bDLE for 30 minutes and then removing them from treatment. From 0 to 7 hours after the bDLE was completely removed from the extracellular compartment, HIV-1 was then added to the host cells. The bDLE was found to protect the cells from HIV-1 infection, an effect that was retained for several hours.</p> <p>Conclusions</p> <p>bDLE acted as an antiviral compound and prevented host cell infection by HIV-1 at all viral life cycle stages. These cell protection effects lingered for hours after the bDLE was removed. Interestingly, bDLE inhibited fusion of fusogenic cells by acting only on CD4 cells. bDLE had no virucidal effect, but could retain its antiviral effect on target cells after it was removed from the extracellular compartment, protecting the cells from infection for hours.</p> <p>bDLE, which has no reported side effects or toxicity in clinical trials, should therefore be further studied to determine its potential use as a therapeutic agent in HIV-1 infection therapy, in combination with known antiretrovirals.</p
Yeasts associated with the production of distilled alcoholic beverages
Distilled alcoholic beverages are produced firstly by fermenting sugars emanating from cereal starches (in the case of whiskies), sucrose-rich plants (in the case of rums), fructooligosaccharide-rich plants (in the case of tequila) or from fruits (in the case of brandies). Traditionally, such fermentations were conducted in a spontaneous fashion, relying on indigenous microbiota, including wild yeasts. In modern practices, selected strains of Saccharomyces cerevisiae are employed to produce high levels of ethanol together with numerous secondary metabolites (eg. higher alcohols, esters, carbonyls etc.) which greatly influence the final flavour and aroma characteristics of spirits following distillation of the fermented wash. Therefore, distillers, like winemakers, must carefully choose their yeast strain which will be very important in providing the alcohol content and the sensory profiles of spirit beverages. This Chapter discusses yeast and fermentation aspects associated with the production of selected distilled spirits and highlights similarities and differences with the production of wine
Colorado Plateau Coring Project, Phase I (CPCP-I): a continuously cored, globally exportable chronology of Triassic continental environmental change from western North America
Phase 1 of the Colorado Plateau Coring
Project (CPCP-I) recovered a total of over 850 m of stratigraphically
overlapping core from three coreholes at two sites in the Early to Middle
and Late Triassic age largely fluvial Moenkopi and Chinle formations in
Petrified Forest National Park (PFNP), northeastern Arizona, USA. Coring took
place during November and December of 2013 and the project is now in its
post-drilling science phase. The CPCP cores have abundant detrital
zircon-producing layers (with survey LA-ICP-MS dates selectively resampled
for CA-ID-TIMS U-Pb ages ranging in age from at least 210 to 241 Ma), which
together with their magnetic polarity stratigraphy demonstrate that a
globally exportable timescale can be produced from these continental
sequences and in the process show that a prominent gap in the calibrated
Phanerozoic record can be filled. The portion of core CPCP-PFNP13-1A for
which the polarity stratigraphy has been completed thus far spans ∼ 215
to 209 Ma of the Late Triassic age, and strongly validates the longer
Newark-Hartford Astrochronostratigraphic-calibrated magnetic Polarity
Time-Scale (APTS) based on cores recovered in the 1990s during the Newark
Basin Coring Project (NBCP).Core recovery was ∼ 100 % in all holes (Table 1). The coreholes were
inclined ∼ 60–75° approximately to the south to ensure azimuthal
orientation in the nearly flat-lying bedding, critical to the interpretation
of paleomagentic polarity stratigraphy. The two longest of the cores
(CPCP-PFNP13-1A and 2B) were CT-scanned in their entirety at the University
of Texas High Resolution X-ray CT Facility in Austin, TX, and subsequently
along with 2A, all cores were split and processed at the CSDCO/LacCore
Facility, in Minneapolis, MN, where they were scanned for physical property
logs and imaging. While remaining the property of the Federal Government, the
archive half of each core is curated at the NSF-sponsored LacCore Core
Repository and the working half is stored at the Rutgers University Core
Repository in Piscataway, NJ, where the initial sampling party was held in
2015 with several additional sampling events following. Additional planned
study will recover the rest of the polarity stratigraphy of the cores as
additional zircon ages, sedimentary structure and paleosol facies analysis,
stable isotope geochemistry, and calibrated XRF core scanning are
accomplished. Together with strategic outcrop studies in Petrified Forest
National Park and environs, these cores will allow the vast amount of surface
paleontological and paleoenvironmental information recorded in the
continental Triassic of western North America to be confidently placed in a
secure context along with important events such as the giant Manicouagan
impact at ∼ 215.5 Ma (Ramezani et al., 2005) and long wavelength
astronomical cycles pacing global environmental change and trends in
atmospheric gas composition during the dawn of the dinosaurs.</p
Estimating Contact Process Saturation in Sylvatic Transmission of Trypanosoma cruzi in the United States
Although it has been known for nearly a century that strains of Trypanosoma cruzi, the etiological agent for Chagas' disease, are enzootic in the southern U.S., much remains unknown about the dynamics of its transmission in the sylvatic cycles that maintain it, including the relative importance of different transmission routes. Mathematical models can fill in gaps where field and lab data are difficult to collect, but they need as inputs the values of certain key demographic and epidemiological quantities which parametrize the models. In particular, they determine whether saturation occurs in the contact processes that communicate the infection between the two populations. Concentrating on raccoons, opossums, and woodrats as hosts in Texas and the southeastern U.S., and the vectors Triatoma sanguisuga and Triatoma gerstaeckeri, we use an exhaustive literature review to derive estimates for fundamental parameters, and use simple mathematical models to illustrate a method for estimating infection rates indirectly based on prevalence data. Results are used to draw conclusions about saturation and which population density drives each of the two contact-based infection processes (stercorarian/bloodborne and oral). Analysis suggests that the vector feeding process associated with stercorarian transmission to hosts and bloodborne transmission to vectors is limited by the population density of vectors when dealing with woodrats, but by that of hosts when dealing with raccoons and opossums, while the predation of hosts on vectors which drives oral transmission to hosts is limited by the population density of hosts. Confidence in these conclusions is limited by a severe paucity of data underlying associated parameter estimates, but the approaches developed here can also be applied to the study of other vector-borne infections
Bird-Like Anatomy, Posture, and Behavior Revealed by an Early Jurassic Theropod Dinosaur Resting Trace
BACKGROUND: Fossil tracks made by non-avian theropod dinosaurs commonly reflect the habitual bipedal stance retained in living birds. Only rarely-captured behaviors, such as crouching, might create impressions made by the hands. Such tracks provide valuable information concerning the often poorly understood functional morphology of the early theropod forelimb. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe a well-preserved theropod trackway in a Lower Jurassic ( approximately 198 million-year-old) lacustrine beach sandstone in the Whitmore Point Member of the Moenave Formation in southwestern Utah. The trackway consists of prints of typical morphology, intermittent tail drags and, unusually, traces made by the animal resting on the substrate in a posture very similar to modern birds. The resting trace includes symmetrical pes impressions and well-defined impressions made by both hands, the tail, and the ischial callosity. CONCLUSIONS/SIGNIFICANCE: The manus impressions corroborate that early theropods, like later birds, held their palms facing medially, in contrast to manus prints previously attributed to theropods that have forward-pointing digits. Both the symmetrical resting posture and the medially-facing palms therefore evolved by the Early Jurassic, much earlier in the theropod lineage than previously recognized, and may characterize all theropods
Seroprevalence of T. Cruzi infection in blood donors and chagas cardiomyopathy in patients from the coal mining region of coahuila, Mexico
Context and Objective: Chagas disease is considered a worldwide emerging disease; it is endemic in Mexico and the state of Coahuila and is considered of little relevance. The objective of this study was to determine the seroprevalence of T. cruzi infection in blood donors and Chagas cardiomyopathy in patients from the coal mining region of Coahuila, Mexico. Design and Setting:
Epidemiological, exploratory and prospective study in a general hospital during the period January to June 2011. Methods: We performed laboratory tests ELISA and indirect hemagglutination in three groups of individuals: 1) asymptomatic voluntary blood donors, 2) patients hospitalized in the cardiology department and 3) patients with dilated cardiomyopathy. Results: There were three
levels of seroprevalence: 0.31% in asymptomatic individuals, 1.25% in cardiac patients and in patients with dilated cardiomyopathy in 21.14%. Conclusions: In spite of having detected autochthonous cases of Chagas disease, its importance to local public health
remains to be established as well as the details of the dynamics of transmission so that the study is still in progress
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