Oxidative stress may be the unifying mechanism underlying the development of comorbidities in obesity. Evidence suggests that a clustering of sources of oxidative stress exists in obesity: ...hyperglycemia, hyperleptinemia, increased tissue lipid levels, inadequate antioxidant defenses, increased rates of free radical formation, enzymatic sources within the endothelium, and chronic inflammation.
This review provides a summary of the available evidence on systemic oxidative stress in humans and specific metabolic pathways by which obesity may elevate systemic oxidant stress. The authors suggest possible methods of reducing oxidative stress such as antioxidant supplementation, caloric restriction and/or physical activity and surgical intervention to combat free radicals and reduce adipose tissue.
Obesity is associated with oxidative stress and can be reduced with weight loss (regardless of exercise or surgery induced weight loss), caloric restriction or antioxidant rich diets.
Oxidative stress levels are elevated in human obesity, and these levels are modifiable with various lifestyle modifications and surgical interventions.
SUMMARY
We present a new method for estimating time-series of relative seismic velocity changes (dv/v) within the Earth. Our approach is a Markov chain Monte Carlo (MCMC) technique that seeks to ...construct the full posterior probability distribution of the dv/v variations. Our method provides a robust, computationally efficient way to compute dv/v time-series that can incorporate information about measurement uncertainty, and any prior constraints that may be available. We demonstrate the method with a synthetic experiment, and then apply the MCMC algorithm to three data examples. In the first two examples we reproduce dv/v time-series associated with the response to the 2010 M 7.2 El Mayor-Cucapah earthquake at two sites in southern California, that have been studied in previous literature. In the San Jacinto fault zone environment we reproduce the dv/v signature of a deep creep slip sequence triggered by the El Mayor-Cucapah event, that is superimposed on a strong seasonal signal. At the Salton Sea Geothermal Field we corroborate the previously observed drop-and-recovery in seismic velocity caused by ground shaking related to the El Mayor-Cucapah event. In a third, new example we compute a month long velocity change time-series at hourly resolution at Piñon Flat, California. We observe a low amplitude variation in seismic velocity with a dominant frequency of 1 cycle per day, as well as a second transient signal with a frequency of 1.93 cycles per day. We attribute the 1-d periodicity in the dv/v variation to the combined effects of the diurnal tide and solar heating. The frequency of the signal at 1.93 cycles per day matches that of the lunar (semi-diurnal) tide. Analysis of the uncertainties in the Piñon Flat time-series shows that the error contains a signal with a frequency of 1 cycle per day. We attribute this variation to seismic noise produced by freight trains operating within the Coachella Valley. By demonstrating the applicability of the MCMC method in these examples, we show that it is well suited to tackle problems involving large data volumes that are typically associated with modern seismic experiments.
Evidence for primordial water in Earth's deep mantle Hallis, Lydia J.; Huss, Gary R.; Nagashima, Kazuhida ...
Science (American Association for the Advancement of Science),
11/2015, Letnik:
350, Številka:
6262
Journal Article
Recenzirano
Odprti dostop
The hydrogen-isotope deuterium/hydrogen (D/H) ratio of Earth can be used to constrain the origin of its water. However, the most accessible reservoir, Earth's oceans, may no longer represent the ...original (primordial) D/H ratio, owing to changes caused by water cycling between the surface and the interior. Thus, a reservoir completely isolated from surface processes is required to define Earth's original D/H signature. Here we present data for Baffin Island and Icelandic lavas, which suggest that the deep mantle has a low D/H ratio (δD more negative than –218 per mil). Such strongly negative values indicate the existence of a component within Earth's interior that inherited its D/H ratio directly from the protosolar nebula.
To establish a biological profile and disease aetiologies for one of four burials recovered during a Time Team dig at the St. Mary Magdalen
leprosarium
, Winchester, UK in AD 2000. Osteological ...techniques were applied to estimate age at death, biological sex, stature and pathology. Visual assessment of the material was supplemented by radiographic examination. Evidence for leprosy DNA was sought using ancient DNA (aDNA) analysis. The remains are those of a male individual excavated from a west–east aligned grave. The skeleton shows signs of two pathologies. Remodelling of the rhino-maxillary area and degenerative changes to small bones of the feet and reactive bone on the distal lower limbs suggest a multibacillary form of leprosy, whereas the right tibia and fibula show the presence of a primary neoplasm identified as an osteosarcoma. The aDNA study confirmed presence of
Mycobacterium leprae
in several skeletal elements, and the strain was genotyped to the 3I lineage, one of two main SNP types present in mediaeval Britain and ancestral to extant strains in America. This is a rare documentation of leprosy in association with a primary neoplasm.
This book was produced by the Zoological Society of London and the University of Cambridge with two aims: to assess seabirds’ vulnerability to climate change in the North-East Atlantic, and to ...identify potential conservation actions that could reduce this vulnerability. 'Seabirds in the North-East Atlantic' collates information from the scientific literature, non-governmental organisations’ reports, conservation practitioner input and online databases into a single volume, and provides a reference manual to assist conservation planning. It is intended to be used by anyone who wishes to identify climate change threats to seabirds; to compare threats between different areas of the North-East Atlantic; to start a quantitative climate change vulnerability assessment for a local population; or to review options for conservation action in response to climate change. This book stems from research published in December 2022, but assessments may be updated based on feedback and newly available information. To check for updates to our assessments, please visit our website at: www.ZSL.org/seabird-guidelines.
The radio galaxy 0402+379 is believed to host a supermassive black hole binary (SMBHB). The two compact-core sources are separated by a projected distance of 7.3 pc, making it the most (spatially) ...compact resolved SMBHB known. We present new multi-frequency VLBI observations of 0402+379 at 5, 8, 15, and 22 GHz and combine them with previous observations spanning 12 years. A strong frequency-dependent core shift is evident, which we use to infer magnetic fields near the jet base. After correcting for these shifts we detect significant relative motion of the two cores at at . With some assumptions about the orbit, we use this measurement to constrain the orbital period yr and SMBHB mass . While additional observations are needed to confirm this motion and obtain a precise orbit, this is apparently the first black hole system resolved as a visual binary.
A sunlit conductive spacecraft, immersed in tenuous plasma, will attain a positive potential relative to the ambient plasma. This potential is primarily governed by solar irradiation, which causes ...escape of photoelectrons from the surface of the spacecraft, and the electrons in the ambient plasma providing the return current. In this paper we combine potential measurements from the Cluster satellites with measurements of extreme ultraviolet radiation from the TIMED satellite to establish a relation between solar radiation and spacecraft charging from solar maximum to solar minimum. We then use this relation to derive an improved method for determination of the current balance of the spacecraft. By calibration with other instruments we thereafter derive the plasma density. The results show that this method can provide information about plasma densities in the polar cap and magnetotail lobe regions where other measurements have limitations.
Key Points
Plasma density estimates from SC‐potentials varies with EUV during solar cycle
Rhabdomyosarcoma (RMS) is a childhood cancer originating from skeletal muscle, and patient survival is poor in the presence of metastatic disease. Few determinants that regulate metastasis ...development have been identified. The receptor tyrosine kinase FGFR4 is highly expressed in RMS tissue, suggesting a role in tumorigenesis, although its functional importance has not been defined. Here, we report the identification of mutations in FGFR4 in human RMS tumors that lead to its activation and present evidence that it functions as an oncogene in RMS. Higher FGFR4 expression in RMS tumors was associated with advanced-stage cancer and poor survival, while FGFR4 knockdown in a human RMS cell line reduced tumor growth and experimental lung metastases when the cells were transplanted into mice. Moreover, 6 FGFR4 tyrosine kinase domain mutations were found among 7 of 94 (7.5%) primary human RMS tumors. The mutants K535 and E550 increased autophosphorylation, Stat3 signaling, tumor proliferation, and metastatic potential when expressed in a murine RMS cell line. These mutants also transformed NIH 3T3 cells and led to an enhanced metastatic phenotype. Finally, murine RMS cell lines expressing the K535 and E550 FGFR4 mutants were substantially more susceptible to apoptosis in the presence of a pharmacologic FGFR inhibitor than the control cell lines expressing the empty vector or wild-type FGFR4. Together, our results demonstrate that mutationally activated FGFR4 acts as an oncogene, and these are what we believe to be the first known mutations in a receptor tyrosine kinase in RMS. These findings support the potential therapeutic targeting of FGFR4 in RMS.
We have shown from both simulations and experiments that zwitterion functionalized carbon nanotubes (CNTs) can be used to construct highly efficient desalination membranes. Our simulations predicted ...that zwitterion functional groups at the ends of CNTs allow a high flux of water, while rejecting essentially all ions. We have synthesized zwitterion functionalized CNT/polyamide nanocomposite membranes with varying loadings of CNTs and assessed these membranes for water desalination. The CNTs within the polyamide layer were partially aligned through a high-vacuum filtration step during membrane synthesis. Addition of zwitterion functionalized CNTs into a polyamide membrane increased both the flux of water and the salt rejection ratio. The flux of water was found to increase by more than a factor of 4, from 6.8 to 28.7 GFD (gallons per square foot per day), as the fraction of CNTs was increased from 0 to 20 wt %. Importantly, the ion rejection ratio increased slightly from 97.6% to 98.6%. Thus, the nanotubes imparted an additional transport mechanism to the polyamide membrane, having higher flow rate and the same or slightly better selectivity. Simulations show that when two zwitterions are attached to each end of CNTs having diameters of about 15 Å, the ion rejection ratio is essentially 100%. In contrast, the rejection ratio for nonfunctionalized CNTs is about 0%, and roughly 20% for CNTs having five carboxylic acid groups per end. The increase in ion rejection for the zwitterion functionalized CNTs is due to a combination of steric hindrance from the functional groups partially blocking the tube ends and electrostatic repulsion between functional groups and ions, with steric effects dominating. Theoretical predictions indicate that an ideal CNT/polymer membrane having a loading of 20 wt % CNTs would have a maximum flux of about 20000 GFD at the conditions of our experiments.
Taylor G. Petrey's trenchant history takes a landmark step forward in documenting and theorizing about Latter-day Saints (LDS) teachings on gender, sexual difference, and marriage. Drawing on deep ...archival research, Petrey situates LDS doctrines in gender theory and American religious history since World War II. His challenging conclusion is that Mormonism is conflicted between ontologies of gender essentialism and gender fluidity, illustrating a broader tension in the history of sexuality in modernity itself. As Petrey details, LDS leaders have embraced the idea of fixed identities representing a natural and divine order, but their teachings also acknowledge that sexual difference is persistently contingent and unstable. While queer theorists have built an ethics and politics based on celebrating such sexual fluidity, LDS leaders view it as a source of anxiety and a tool for the shaping of a heterosexual social order. Through public preaching and teaching, the deployment of psychological approaches to "cure" homosexuality, and political activism against equal rights for women and same-sex marriage, Mormon leaders hoped to manage sexuality and faith for those who have strayed from heteronormativity.
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