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2.
Nature ; 607(7918): 256-259, 2022 07.
Article in English | MEDLINE | ID: mdl-35831603

ABSTRACT

Fast radio bursts (FRBs) are millisecond-duration flashes of radio waves that are visible at distances of billions of light years1. The nature of their progenitors and their emission mechanism remain open astrophysical questions2. Here we report the detection of the multicomponent FRB 20191221A and the identification of a periodic separation of 216.8(1) ms between its components, with a significance of 6.5σ. The long (roughly 3 s) duration and nine or more components forming the pulse profile make this source an outlier in the FRB population. Such short periodicity provides strong evidence for a neutron-star origin of the event. Moreover, our detection favours emission arising from the neutron-star magnetosphere3,4, as opposed to emission regions located further away from the star, as predicted by some models5.

3.
Nature ; 577(7789): 190-194, 2020 01.
Article in English | MEDLINE | ID: mdl-31907402

ABSTRACT

Fast radio bursts (FRBs) are brief, bright, extragalactic radio flashes1,2. Their physical origin remains unknown, but dozens of possible models have been postulated3. Some FRB sources exhibit repeat bursts4-7. Although over a hundred FRB sources have been discovered8, only four have been localized and associated with a host galaxy9-12, and just one of these four is known to emit repeating FRBs9. The properties of the host galaxies, and the local environments of FRBs, could provide important clues about their physical origins. The first known repeating FRB, however, was localized to a low-metallicity, irregular dwarf galaxy, and the apparently non-repeating sources were localized to higher-metallicity, massive elliptical or star-forming galaxies, suggesting that perhaps the repeating and apparently non-repeating sources could have distinct physical origins. Here we report the precise localization of a second repeating FRB source6, FRB 180916.J0158+65, to a star-forming region in a nearby (redshift 0.0337 ± 0.0002) massive spiral galaxy, whose properties and proximity distinguish it from all known hosts. The lack of both a comparably luminous persistent radio counterpart and a high Faraday rotation measure6 further distinguish the local environment of FRB 180916.J0158+65 from that of the single previously localized repeating FRB source, FRB 121102. This suggests that repeating FRBs may have a wide range of luminosities, and originate from diverse host galaxies and local environments.

4.
Z Gesundh Wiss ; 26(5): 509-514, 2018.
Article in English | MEDLINE | ID: mdl-30294522

ABSTRACT

PURPOSE: Open Source Intelligence (OSINT) and Signals Intelligence (SIGINT) from the clandestine intelligence sector are being increasingly employed in infectious disease outbreaks. The purpose of this article is to explore how such tools might be employed in the detection, reporting, and control of outbreaks designated as a 'threat' by the global community. It is also intended to analyse previous use of such tools during the Ebola and SARS epidemics and to discuss key questions regarding the ethics and legality of initiatives that further blur the military and humanitarian spaces. METHODS: We undertake qualitative analysis of current discussions on OSINT and SIGINT and their intersection with global health. We also review current literature and describe the debates. We built on quantitative and qualitative research done into current health collection capabilities. RESULTS: This article presents an argument for the use of OSINT in the detection of infectious disease outbreaks and how this might occur. CONCLUSION: We conclude that there is a place for OSINT and SIGINT in the detection and reporting of outbreaks. However, such tools are not sufficient on their own and must be corroborated for the intelligence to be relevant and actionable. Finally, we conclude that further discussion on key ethical issues needs to take place before such research can continue. In particular, this involves questions of jurisdiction, data ownership, and ethical considerations.

5.
Phys Rev Lett ; 121(2): 022003, 2018 Jul 13.
Article in English | MEDLINE | ID: mdl-30085720

ABSTRACT

We present a first-principles lattice QCD+QED calculation at physical pion mass of the leading-order hadronic vacuum polarization contribution to the muon anomalous magnetic moment. The total contribution of up, down, strange, and charm quarks including QED and strong isospin breaking effects is a_{µ}^{HVP LO}=715.4(18.7)×10^{-10}. By supplementing lattice data for very short and long distances with R-ratio data, we significantly improve the precision to a_{µ}^{HVP LO}=692.5(2.7)×10^{-10}. This is the currently most precise determination of a_{µ}^{HVP LO}.

6.
J Prev Alzheimers Dis ; 4(2): 69-70, 2017.
Article in English | MEDLINE | ID: mdl-29177136

Subject(s)
Aging , Humans
7.
Occup Environ Med ; 74(6): 417-421, 2017 06.
Article in English | MEDLINE | ID: mdl-28062833

ABSTRACT

OBJECTIVES: Increased cancer risks have been reported among workers in the rubber manufacturing industry employed before the 1960s, but it is unclear for workers hired subsequently. The present study focused on cancer incidence among rubber workers first employed after 1975 in Sweden and the UK. METHODS: Two cohorts of rubber workers employed for at least 1 year were analysed. Standardised incidence ratios (SIRs), based on country-specific and period-specific incidence rates, were analysed for all cancers combined (except non-melanoma skin), bladder, lung, stomach cancer, leukaemia, non-Hodgkin's lymphoma and multiple myeloma. Exploratory analyses were conducted for other cancers with a minimum of 10 cases in both genders combined. RESULTS: 16 026 individuals (12 441 men; 3585 women) contributed to 397 975 person-years of observation, with 846 cancers observed overall (437 in the UK, 409 in Sweden). No statistically significant increased risk was observed for any site of cancer. A reduced risk was evident for all cancers combined (SIR=0.83, 95% CI (0.74 to 0.92)), lung cancer (SIR=0.74, 95% CI (0.59 to 0.93)), non-Hodgkin's lymphoma (SIR=0.67, 95% CI (0.45 to 1.00)) and prostate cancer (SIR=0.77, 95% CI (0.64 to 0.92)). For stomach cancer and multiple myeloma, SIRs were 0.93 (95% CI (0.61 to 1.43)) and 0.92 (95% CI 0.44 to 1.91), respectively. No increased risk of bladder cancer was observed (SIR=0.88, 95% CI (0.61 to 1.28)). CONCLUSIONS: No significantly increased risk of cancer incidence was observed in the combined cohort of rubber workers first employed since 1975. Continued surveillance of the present cohorts is required to confirm absence of long-term risk and confirmatory findings from other cohorts would be important.


Subject(s)
Neoplasms/chemically induced , Neoplasms/epidemiology , Occupational Diseases/chemically induced , Occupational Diseases/epidemiology , Occupational Exposure/adverse effects , Rubber/adverse effects , Adult , Cohort Studies , Female , Humans , Incidence , Male , Manufacturing Industry , Middle Aged , Poisson Distribution , Sex Distribution , Sweden/epidemiology , United Kingdom/epidemiology , Urinary Bladder Neoplasms/epidemiology , Young Adult
8.
Dalton Trans ; 46(3): 647-650, 2017 Jan 17.
Article in English | MEDLINE | ID: mdl-27891545

ABSTRACT

A highly tunable phosphine-imine ligand family is introduced. Following metallation with ruthenium, deprotonation of the ligand affords a phosphine-enamido species. Complexes with the ligand in both the imine and enamido forms are active toward acceptorless dehydrogenation reactions.

9.
Phys Rev Lett ; 116(23): 232002, 2016 Jun 10.
Article in English | MEDLINE | ID: mdl-27341226

ABSTRACT

We report the first lattice QCD calculation of the hadronic vacuum polarization (HVP) disconnected contribution to the muon anomalous magnetic moment at physical pion mass. The calculation uses a refined noise-reduction technique that enables the control of statistical uncertainties at the desired level with modest computational effort. Measurements were performed on the 48^{3}×96 physical-pion-mass lattice generated by the RBC and UKQCD Collaborations. We find the leading-order hadronic vacuum polarization a_{µ}^{HVP(LO)disc}=-9.6(3.3)(2.3)×10^{-10}, where the first error is statistical and the second systematic.

10.
Eur Ann Otorhinolaryngol Head Neck Dis ; 133 Suppl 1: S61-2, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27246747

ABSTRACT

Today increasing numbers of cochlear implant candidates have residual hearing that can be aided and hence is worth trying to preserve. This means that surgical technique and electrode array design must be adapted to minimize trauma. Wide opening of the round window is often preferred to reduce drill related trauma and to avoid pressure spikes during electrode array insertion. A recent meta-analysis suggested that there is no significant correlation between hearing preservation and either insertion depth or scala position. However, a slow insertion speed of at least 30seconds was associated with better hearing preservation. An electrode design is proposed that targets the middle of the scala tympani. This minimizes frictional forces from either lateral or medial wall during insertion and imposes less static pressure on cochlear structures following insertion. The flexibility to insert via the round window requires a 0.7-mm maximum dimension at the proximal end of the array. Micro-anatomical analysis by micro-CT indicated that a 420-degree insertion depth was optimal between cochlear coverage and available space within the scala tympani. Physical measurements showed that mean insertion forces remained below 10mN during insertion. A series of 20 human temporal bone insertions found a mean insertion depth of 400 degrees with no scala dislocations. Six clinical series, in total 94 cases, found postoperative hearing in 81% of cases with a mean loss of 12dB compared to preoperative levels. Speech understanding out to one year post-fitting trended better for a mid-scala design group than for a straight electrode array group; although the differences were not statistically significant. A mid-scala array design appears able to be inserted with minimal trauma, to return a predictable insertion depth across various sizes of cochleae and to support reasonable levels of speech understanding without relying on residual hearing.


Subject(s)
Cochlear Implantation/methods , Cochlear Implants , Prosthesis Design , Humans , Intraoperative Complications/prevention & control , Round Window, Ear
11.
Ann Oncol ; 27(5): 933-41, 2016 05.
Article in English | MEDLINE | ID: mdl-26884594

ABSTRACT

BACKGROUND: Increased cancer risk has been reported among workers in the rubber manufacturing industry employed before the 1960s. It is unclear whether risk remains increased among workers hired subsequently. The present study focused on risk of cancer mortality for rubber workers first employed since 1975 in 64 factories. PATIENTS AND METHODS: Anonymized data from cohorts of rubber workers employed for at least 1 year from Germany, Italy, Poland, Sweden, and the UK were pooled. Standardized mortality ratios (SMRs), based on country-specific death rates, were reported for bladder and lung cancer (primary outcomes of interest), for other selected cancer sites, and for cancer sites with a minimum of 10 deaths in men or women. Analyses stratified by type of industry, period, and duration of employment were carried out. RESULTS: A total of 38 457 individuals (29 768 men; 8689 women) contributed to 949 370 person-years. No increased risk of bladder cancer was observed [SMR = 0.80, 95% confidence interval (CI) 0.46; 1.38]. The risk of lung cancer death was reduced (SMR = 0.81, 95% CI 0.70; 0.94). No statistically significant increased risk was observed for any other cause of death. A reduced risk was evident for total cancer mortality (SMR = 0.81, 95% CI 0.76; 0.87). Risks were lower for workers in the tyre industry compared with workers in the general rubber goods sector. Analysis by employment duration showed a negative trend with SMRs decreasing with increasing duration of employment. In an analysis of secondary end points, when stratified by type of industry and period of first employment, excess risks of myeloma and gastric cancer were observed each due, essentially, to results from one centre. CONCLUSION: No consistent increased risk of cancer death was observed among rubber workers first employed since 1975, no overall analysis of the pooled cohort produced significantly increased risk. Continued surveillance of the present cohorts is required to confirm the absence of long-term risk.


Subject(s)
Lung Neoplasms/mortality , Neoplasms/mortality , Occupational Exposure/adverse effects , Urinary Bladder Neoplasms/mortality , Adult , Aged , Cohort Studies , Female , Humans , Lung Neoplasms/chemically induced , Lung Neoplasms/pathology , Male , Manufacturing Industry , Middle Aged , Neoplasms/chemically induced , Neoplasms/pathology , Rubber/toxicity , Urinary Bladder Neoplasms/chemically induced , Urinary Bladder Neoplasms/pathology
12.
Dalton Trans ; 45(7): 2868-80, 2016 Feb 21.
Article in English | MEDLINE | ID: mdl-26792103

ABSTRACT

Ferrocene-based phosphines constitute an important auxiliary ligand in inorganic chemistry. Utilizing the (ferrocenylethyl)phosphines (FcCH2CH2)3-nHnP (Fc = ferrocenyl; n = 2, 1; n = 1, 2; n = 0, 3) the synthesis of a series of coordination complexes [(FcCH2CH2)3-nHnPCuCl]4 (n = 2, 1-CuCl; n = 0, 3-CuCl), [(FcCH2CH2)2HPCuCl] (2-CuCl), {[(FcCH2CH2)H2P]2AgCl}2 (1-AgCl), [(FcCH2CH2)2HPAgCl] (2-AgCl), [(FcCH2CH2)3PAgCl]4 (3-AgCl), [(FcCH2CH2)3PM(OAc)]4 (M = Cu, 3-CuOAc M = Ag, 3-AgOAc), [(FcCH2CH2)3-nHnPAuCl] (n = 1, 2-AuCl; n = 0, 3-AuCl), via the reaction between the free phosphine and MX (M = Cu, Ag and Au; X = Cl, OAc), is described. The reaction between the respective phosphine with a suspension of metal-chloride or -acetate in a 1 : 1 ratio in THF at ambient temperature affords coordinated phosphine-coinage metal complexes. Varying structural motifs are observed in the solid state, as determined via single crystal X-ray analysis of 1-CuCl, 3-CuCl, 1-AgCl, 3-AgCl, 3-CuOAc, 3-AgOAc, 2-AuCl and 3-AuCl. Complexes 1-CuCl and 3-CuCl are tetrameric Cu(i) cubane-like structures with a Cu4Cl4 core, whereas silver complexes with primary and tertiary phosphine reveal two different structural types. The structure of 1-AgCl, unlike the rest, displays the coordination of two phosphines to each silver atom and shows a quadrangle defined by two Ag and two Cl atoms. In contrast, 3-AgCl is distorted from a cubane structure via elongation of one of the ClAg distances. 3-CuOAc and 3-AgOAc are isostructural with step-like cores, while complexes 2-AuCl and 3-AuCl reveal a linear geometry of a phosphine gold(i) chloride devoid of any aurophilic interactions. All of the complexes were characterized in solution by multinuclear (1)H, (13)C{(1)H} and (31)P NMR spectroscopic techniques; the redox chemistry of the series of complexes was examined using cyclic voltammetry. This class of complexes has been found to exhibit one reversible Fe(ii)/Fe(iii) oxidation couple, suggesting the absence of electronic communication between the ferrocenyl units on individual phosphine ligands as well as between different phosphines on the polymetallic cores.

13.
Phys Rev Lett ; 115(21): 212001, 2015 Nov 20.
Article in English | MEDLINE | ID: mdl-26636846

ABSTRACT

We report the first lattice QCD calculation of the complex kaon decay amplitude A_{0} with physical kinematics, using a 32³×64 lattice volume and a single lattice spacing a, with 1/a=1.3784(68) GeV. We find Re(A_{0})=4.66(1.00)(1.26)×10(-7) GeV and Im(A_{0})=-1.90(1.23)(1.08)×10(-11) GeV, where the first error is statistical and the second systematic. The first value is in approximate agreement with the experimental result: Re(A_{0})=3.3201(18)×10(-7) GeV, while the second can be used to compute the direct CP-violating ratio Re(ϵ^{'}/ϵ)=1.38(5.15)(4.59)×10^{-4}, which is 2.1σ below the experimental value 16.6(2.3)×10(-4). The real part of A_{0} is CP conserving and serves as a test of our method while the result for Re(ϵ^{'}/ϵ) provides a new test of the standard model theory of CP violation, one which can be made more accurate with increasing computer capability.

14.
Br J Cancer ; 112(7): 1247-50, 2015 Mar 31.
Article in English | MEDLINE | ID: mdl-25826226

ABSTRACT

BACKGROUND: No analytic epidemiological study has examined the relationship between use of muscle-building supplements (MBSs) and testicular germ cell cancer (TGCC) risk. METHODS: We conducted a population-based case-control study including 356 TGCC cases and 513 controls from Connecticut and Massachusetts. RESULTS: The odds ratio (OR) for ever use of MBSs in relation to risk of TGCC was significantly elevated (OR=1.65, 95% confidence interval (CI): 1.11-2.46). The associations were significantly stronger among early users, men with more types of MBSs used, and longer periods of use. CONCLUSIONS: MBS use is a potentially modifiable risk factor that may be associated with TGCC.


Subject(s)
Dietary Supplements/statistics & numerical data , Muscle Strength/drug effects , Neoplasms, Germ Cell and Embryonal/epidemiology , Testicular Neoplasms/epidemiology , Adult , Case-Control Studies , Connecticut/epidemiology , Dietary Supplements/adverse effects , Humans , Male , Massachusetts/epidemiology , Risk Factors
16.
Chem Commun (Camb) ; 50(17): 2139-41, 2014 Feb 28.
Article in English | MEDLINE | ID: mdl-24419147

ABSTRACT

A terminal and unsupported chromium(III) hydroxide is reported. The terminal hydroxide is used to synthesize the first example of a heterobimetallic Ti-O-Cr compound containing an unsupported µ-oxo bridge. The heterobimetallic complex exhibits a new absorbance at 288 nm (4.32 eV), which is assigned to a metal-to-metal charge transfer (MMCT) transition.


Subject(s)
Chromium/chemistry , Coordination Complexes/chemistry , Hydroxides/chemistry , Oxygen/chemistry , Titanium/chemistry , Coordination Complexes/chemical synthesis , Crystallography, X-Ray , Electrochemical Techniques , Molecular Conformation , Oxidation-Reduction , Solar Energy
17.
AJNR Am J Neuroradiol ; 34(9): E100-2, 2013 Sep.
Article in English | MEDLINE | ID: mdl-22997166

ABSTRACT

SUMMARY: The Kety-Schmidt technique provides quantitative measurement of whole-brain CBF. CBF is measured as the area between the arterial and venous washout curves of a diffusible tracer. Oxygen extraction and metabolism may be calculated from arterial and venous samples. In this report, we present a method for performing these measurements in an MR imaging environment. This technique could be useful for validation of MR imaging methods of hemodynamic and metabolic measurements in humans.


Subject(s)
Algorithms , Brain/metabolism , Magnetic Resonance Angiography/methods , Nitrous Oxide/pharmacokinetics , Oximetry/methods , Oxygen/metabolism , Animals , Brain/anatomy & histology , Computer Simulation , Female , Humans , Image Interpretation, Computer-Assisted/methods , Macaca fascicularis , Male , Models, Biological , Oxygen Consumption/physiology , Papio anubis , Reproducibility of Results , Sensitivity and Specificity
18.
Phys Rev Lett ; 110(15): 152001, 2013 Apr 12.
Article in English | MEDLINE | ID: mdl-25167252

ABSTRACT

There has been much speculation as to the origin of the ΔI=1/2 rule (ReA0/ReA2≃22.5). We find that the two dominant contributions to the ΔI=3/2, K→ππ correlation functions have opposite signs, leading to a significant cancelation. This partial cancelation occurs in our computation of ReA2 with physical quark masses and kinematics (where we reproduce the experimental value of A2) and also for heavier pions at threshold. For ReA0, although we do not have results at physical kinematics, we do have results for pions at zero momentum with mπ≃420 MeV [ReA0/ReA2=9.1(2.1)] and mπ≃330 MeV [ReA0/ReA2=12.0(1.7)]. The contributions which partially cancel in ReA2 are also the largest ones in ReA0, but now they have the same sign and so enhance this amplitude. The emerging explanation of the ΔI=1/2 rule is a combination of the perturbative running to scales of O(2 GeV), a relative suppression of ReA2 through the cancelation of the two dominant contributions, and the corresponding enhancement of ReA0. QCD and electroweak penguin operators make only very small contributions at such scales.

19.
Brain ; 135(Pt 10): 3005-14, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23065790

ABSTRACT

Lewy bodies are common in the ageing brain and often co-occur with Alzheimer's disease pathology. There is little known regarding the independent role of Lewy body pathology in cognition impairment, decline and fluctuations in community-dwelling older persons. We examined the contribution of Lewy body pathology to dementia, global cognition, cognitive domains, cognitive decline and fluctuations in 872 autopsied subjects (mean age = 87.9 years) from the Rush Religious Order Study (n = 491) and Memory and Aging Project (n = 381) longitudinal community-based clinical-pathological studies. Dementia was based on a clinical evaluation; annual cognitive performance tests were used to create a measure of global cognition and five cognitive domains. Lewy body type was determined by using α-synuclein immunostained sections of substantia nigra, limbic and neocortical regions. Statistical models included multiple regression models for dementia and cognition and mixed effects models for decline. Cognitive fluctuations were estimated by comparing standard deviations of individual residuals from mean trajectories of decline in those with and without Lewy bodies. All models controlled for age, sex, education, Alzheimer's disease pathology and infarcts. One hundred and fifty-seven subjects (18%) exhibited Lewy body pathology (76 neocortical-type, 54 limbic-type and 27 nigra-predominant). One hundred and three (66%) subjects with Lewy body pathology had a pathologic diagnosis of Alzheimer's disease. Neocortical-type, but not nigral-predominant or limbic-type Lewy body pathology was related to an increased odds of dementia (odds ratio = 3.21; 95% confidence interval = 1.78-5.81) and lower cognition (P < 0.001) including episodic memory function (P < 0.001) proximate to death. Neocortical-type Lewy body pathology was also related to a faster decline in global cognition (P < 0.001), decline in all five specific cognitive domains (all P-values < 0.001), and to fluctuations in decline of working and semantic memory (P-values < 0.001). Limbic-type Lewy body pathology was related to lower and faster decline in visuospatial skills (P = 0.042). The relationship of Lewy body pathology to cognition and dementia was not modified by Alzheimer's disease pathology. Neocortical-type Lewy body pathology is associated with increased odds of dementia; lower and more rapid decline in all cognitive domains including episodic memory and fluctuations in decline in semantic and working memory. Limbic-type Lewy body pathology is specifically associated with lower and more rapid decline in visuospatial skills. The effect of Lewy body pathology on cognition appears to be independent of Alzheimer's disease pathology.


Subject(s)
Alzheimer Disease/pathology , Cognition Disorders/diagnosis , Cognition Disorders/pathology , Lewy Bodies/pathology , Aged , Aged, 80 and over , Alzheimer Disease/epidemiology , Comorbidity , Female , Humans , Lewy Body Disease/epidemiology , Lewy Body Disease/pathology , Longitudinal Studies , Male , Neuropsychological Tests
20.
Ann Oncol ; 23 Suppl 6: vi7-12, 2012 Aug.
Article in English | MEDLINE | ID: mdl-23012306

ABSTRACT

Breast cancer is a major problem for global public health. Breast Cancer is the most common incident form of cancer in women around the world. The incidence is increasing while mortality is declining in many high-income countries. The last decade has seen a revolution in the understanding of breast cancer, with new classifications proposed that have significant prognostic value and provide guides to treatment options. Breast cancers that demonstrate the absence of oestrogen receptor and progesterone receptor and no overexpression of human epidermal growth factor receptor 2 (HER2) are referred to as triple-negative breast cancer (TNBC). There is now evidence emerging from epidemiological studies regarding important characteristics of this group of tumours that carry a relatively poorer prognosis than the major breast cancer sub-types. From this review of available data and information, there are some consistent findings that emerge. Women with TNBC experience the peak risk of recurrence within 3 years of diagnosis, and the mortality rates appear to be increased for 5 years after diagnosis. TNBC represents 10%-20% of invasive breast cancers and has been associated with African-American race, deprivation status, younger age at diagnosis, more advanced disease stage, higher grade, high mitotic indices, family history of breast cancer and BRCA1 mutations. TNBC is regularly reported to be three times more common in women of African descent and in pre-menopausal women, and carries a poorer prognosis than other forms of breast cancer. Although prospects for prevention of non-hormone-dependent breast cancer are currently poor, it is still important to understand the aetiology of such tumours. There remains a great deal of work to be done to arrive at a comprehensive picture of the aetiology of breast cancer. Key recommendations are that there is a clear and urgent need to have more epidemiological studies of the breast cancer sub-types to integrate aetiological and lifestyle factors for prevention of incidence and death, and to have more population-based information of the clinical and biological relevance from cancer registries.


Subject(s)
Breast Neoplasms/epidemiology , Receptor, ErbB-2/metabolism , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Breast Neoplasms/etiology , Breast Neoplasms/metabolism , Female , Humans , Neoplasm Recurrence, Local/epidemiology , Racial Groups , Risk Factors
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