2,761 research outputs found

    The World Trade Center health surveillance program: results of the first 10 years and implications for prevention.

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    BACKGROUND: The terrorist attacks on the World Trade Center (WTC) of September 11, 2001 resulted in the deaths of 2,823 persons. They also generated a long-lasting burden of multiple physical and mental health illnesses among the cohort of 50,000 rescue workers who responded to the attacks and in the 400,000 residents and workers in nearby areas of New York City. A comprehensive health surveillance program was developed from the first months after the accidents and was further developed in the subsequent ears. Individual exposure and health data were stored in ad hoc databases and produced epidemiological outcomes on the various exposure-related illnesses. METHODS: About 10 years of longitudinal assessment of this large cohort of WTC rescue and recovery workers, yielded data from participants in the WTC Screening, Monitoring, and Treatment Program. Police officers, firefighters, construction workers, and municipal workers were included in the cohort. Cumulative and annual incidence were estimated for various physical disorders including asthma, sinusitis, and gastroesophageal reflux disease, mental health disorders including depression, post-traumatic stress disorder [PTSD], and panic disorder. Respiratory functionality was also assessed. Exposure was characterized with qualitative parameter including working on the pile and being engulfed in the dust cloud, and quantitative parameters including the time of arrival on site and the exposure duration. RESULTS: Upper and lower respiratory conditions such as rhinosinusitis and asthma have been found in a significant number of people in WTC-exposed populations. A lack of appropriate respiratory protection may have contributed to these effects. Other commonly observed physical health conditions include gastro-esophageal reflux disease, obstructive sleep apnea and musculo-skeletal injuries. Many WTC-exposed individuals also suffer from mental health conditions, primarily post-traumatic stress disorder, depression, panic disorder, and substantial stress reaction. Recent studies suggest that WTC exposure may increase the risk of cancer and of mortality from cardiac disease. CONCLUSION: Ten years of systematic health surveillance after the 9/11 WTC attacks, show long lasting burden of physical and mental health problems. Continued monitoring and treatment of this population is needed for early diagnoses of initial clinical conditions that can be treated more effectively. The experience of September 11 offers also indications on how to approach the acute and delayed health effects of civilian catastrophes. Critical lessons are derived about the importance of having trained responders--medical and non-medical--in place in advance of disasters, and about the need to proceed with adequate exposure assessment in a timely manner

    Long-distance frequency transfer over an urban fiber link using optical phase stabilization

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    We transferred the frequency of an ultra-stable laser over 86 km of urban fiber. The link is composed of two cascaded 43-km fibers connecting two laboratories, LNE-SYRTE and LPL in Paris area. In an effort to realistically demonstrate a link of 172 km without using spooled fiber extensions, we implemented a recirculation loop to double the length of the urban fiber link. The link is fed with a 1542-nm cavity stabilized fiber laser having a sub-Hz linewidth. The fiber-induced phase noise is measured and cancelled with an all fiber-based interferometer using commercial off the shelf pigtailed telecommunication components. The compensated link shows an Allan deviation of a few 10-16 at one second and a few 10-19 at 10,000 seconds

    Neutrino Oscillations in the Framework of Three-Generation Mixings with Mass Hierarchy

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    We have analyzed the results of reactor and accelerator neutrino oscillation experiments in the framework of a general model with mixing of three neutrino fields and a neutrino mass hierarchy that can accommodate the results of the solar neutrino experiments. It is shown that νμνe \nu_\mu \leftrightarrows \nu_e oscillations with 0.6Δm2100eV2 0.6 \le \Delta m^2 \le 100 \, \mathrm{eV}^2 and amplitude larger than 2×103 2 \times 10^{-3} are not compatible with the existing limits on neutrino oscillations if the non-diagonal elements of the mixing matrix Ue3 \left| U_{e3} \right| and Uμ3 \left| U_{\mu3} \right| are small. Thus, if the excess of electron events recently observed in the LSND experiment is due to νμνe \nu_\mu \leftrightarrows \nu_e oscillations, the mixing in the lepton sector is basically different from the CKM mixing of quarks. If this type of mixing is realized in nature, the observation of νμνe \nu_\mu \leftrightarrows \nu_e oscillations would not influence νμντ \nu_\mu \leftrightarrows \nu_\tau oscillations that are being searched for in the CHORUS and NOMAD experiments.Comment: Revtex file, 13 pages + 2 figures (included). The postscript file of text and figures is available at http://www.to.infn.it/teorici/giunti/papers.html or ftp://ftp.to.infn.it/pub/giunti/1995/dftt-25-95/dftt-25-95.ps.

    Direct visualization reveals dynamics of a transient intermediate during protein assembly

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    Interactions between proteins underlie numerous biological functions. Theoretical work suggests that protein interactions initiate with formation of transient intermediates that subsequently relax to specific, stable complexes. However, the nature and roles of these transient intermediates have remained elusive. Here, we characterized the global structure, dynamics, and stability of a transient, on-pathway intermediate during complex assembly between the Signal Recognition Particle (SRP) and its receptor. We show that this intermediate has overlapping but distinct interaction interfaces from that of the final complex, and it is stabilized by long-range electrostatic interactions. A wide distribution of conformations is explored by the intermediate; this distribution becomes more restricted in the final complex and is further regulated by the cargo of SRP. These results suggest a funnel-shaped energy landscape for protein interactions, and they provide a framework for understanding the role of transient intermediates in protein assembly and biological regulation

    Single and two-particle energy gaps across the disorder-driven superconductor-insulator transition

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    The competition between superconductivity and localization raises profound questions in condensed matter physics. In spite of decades of research, the mechanism of the superconductor-insulator transition (SIT) and the nature of the insulator are not understood. We use quantum Monte Carlo simulations that treat, on an equal footing, inhomogeneous amplitude variations and phase fluctuations, a major advance over previous theories. We gain new microscopic insights and make testable predictions for local spectroscopic probes. The energy gap in the density of states survives across the transition, but coherence peaks exist only in the superconductor. A characteristic pseudogap persists above the critical disorder and critical temperature, in contrast to conventional theories. Surprisingly, the insulator has a two-particle gap scale that vanishes at the SIT, despite a robust single-particle gap.Comment: 7 pages, 5 figures (plus supplement with 4 pages, 5 figures

    Statistical Laws Governing Fluctuations in Word Use from Word Birth to Word Death

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    We analyze the dynamic properties of 10^7 words recorded in English, Spanish and Hebrew over the period 1800--2008 in order to gain insight into the coevolution of language and culture. We report language independent patterns useful as benchmarks for theoretical models of language evolution. A significantly decreasing (increasing) trend in the birth (death) rate of words indicates a recent shift in the selection laws governing word use. For new words, we observe a peak in the growth-rate fluctuations around 40 years after introduction, consistent with the typical entry time into standard dictionaries and the human generational timescale. Pronounced changes in the dynamics of language during periods of war shows that word correlations, occurring across time and between words, are largely influenced by coevolutionary social, technological, and political factors. We quantify cultural memory by analyzing the long-term correlations in the use of individual words using detrended fluctuation analysis.Comment: Version 1: 31 pages, 17 figures, 3 tables. Version 2 is streamlined, eliminates substantial material and incorporates referee comments: 19 pages, 14 figures, 3 table

    Laterally Orienting C. elegans Using Geometry at Microscale for High-Throughput Visual Screens in Neurodegeneration and Neuronal Development Studies

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    C. elegans is an excellent model system for studying neuroscience using genetics because of its relatively simple nervous system, sequenced genome, and the availability of a large number of transgenic and mutant strains. Recently, microfluidic devices have been used for high-throughput genetic screens, replacing traditional methods of manually handling C. elegans. However, the orientation of nematodes within microfluidic devices is random and often not conducive to inspection, hindering visual analysis and overall throughput. In addition, while previous studies have utilized methods to bias head and tail orientation, none of the existing techniques allow for orientation along the dorso-ventral body axis. Here, we present the design of a simple and robust method for passively orienting worms into lateral body positions in microfluidic devices to facilitate inspection of morphological features with specific dorso-ventral alignments. Using this technique, we can position animals into lateral orientations with up to 84% efficiency, compared to 21% using existing methods. We isolated six mutants with neuronal development or neurodegenerative defects, showing that our technology can be used for on-chip analysis and high-throughput visual screens

    Mechanosignaling activation of TGFβ maintains intervertebral disc homeostasis

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    Intervertebral disc (IVD) degeneration is the leading cause of disability with no disease-modifying treatment. IVD degeneration is associated with instable mechanical loading in the spine, but little is known about how mechanical stress regulates nucleus notochordal (NC) cells to maintain IVD homeostasis. Here we report that mechanical stress can result in excessive integrin αv β6-mediated activation of transforming growth factor beta (TGFβ), decreased NC cell vacuoles, and increased matrix proteoglycan production, and results in degenerative disc disease (DDD). Knockout of TGFβ type II receptor (TβRII) or integrin α v in the NC cells inhibited functional activity of postnatal NC cells and also resulted in DDD under mechanical loading. Administration of RGD peptide, TGFβ, and α v β 6-neutralizing antibodies attenuated IVD degeneration. Thus, integrin-mediated activation of TGFβ plays a critical role in mechanical signaling transduction to regulate IVD cell function and homeostasis. Manipulation of this signaling pathway may be a potential therapeutic target to modify DDD
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