Air-sea exchange of CO<SUB>2</SUB> in the Gulf of Kutch, northern Arabian Sea based on bomb-carbon in corals and tree rings

Radiocarbon analyses were carried out in the annual bands of a 40 year old coral collected from the Gulf of Kutch (22.6&#176;N, 70&#176;E) in the northern Arabian Sea and in the annual rings of a teak tree from Thane (19&#176;14'N, 73&#176;24'E) near Bombay. These measurements were made in order to obtain the rates of air-sea exchange of CO2 and the advective mixing of water in the Gulf of Kutch. The &#916;14C peak in the Thane tree occurs in the year 1964, with a value of ~630%, significantly lower than that of the mean atmospheric &#916;14C of the northern hemisphere (~ 1000%). The radiocarbon time series of the coral was modelled considering the supply of carbon and radiocarbon to the gulf through air-sea exchange and advective water transport from the open Arabian Sea. A reasonable fit for the coral data was obtained with an air-sea CO2 exchange rate of 11-12 mol m-2 yr-1, and an advective velocity of 28 m yr-1 between the Arabian Sea and the Gulf of Kutch; this was based on a model generated time series for radiocarbon in the Arabian Sea. The deduced velocity (~ 28 m yr-1) of the advective transport of water between the gulf and the Arabian Sea is much lower than the surface tidal current velocity in this region, but can be understood in terms of net fluxes of carbon and radiocarbon to the gulf to match the observed coral &#916;14C time series

A novel system to obtain addresses of out-patients-assessment in routine clinic practice in Madras

A novel method of obtaining accurate home addresses from out-patients was introduced as a routine procedure in 6 chest clinics of Madras City, following highly satisfactory results under study conditions. In this method, the patient is given a card (the Address card), and asked to get his exact address entered on it by any knowledgeable person of his choice such as the landlord or a neighbour. An assessment of the system was undertaken after it had been in operation for about 8 months. A complete and legible address was available for 82 % of 3956 patients, the range in the 6 clinics being 74% to 91%. The main causes for failure were: not giving Address card to patient (7 %), patient not reattending the clinic (6%), and patient reattending but not returning the Address card (3 %). Corrective measures have now been introduced, and a re-assessment will be undertaken in due course

A novel system to obtain addresses of out-patients-assessent in routine clinic practice in Madras

A novel method of obtaining accurate home addresses from out-patients was introduced as a routine procedure in 6 chest clinics of Madras City, following highly satisfactory results under study conditions. In this method, the patient is given a card (the address card), and asked to get his exact address entered on it by any knowledgeable person of his choice such as a landlord or neighbour. An assessment of the system was undertaken after it had been in operation for about 8 months. A complete and legible address was available for 82 % of 3956 patients, the range in the 6 clinics being 74 % to 91 %. The main causes for failure were : not giving address card to patient (7 %), patient not reattending the clinic (6 %), and patient reattending but not returning the address card (3%). Corrective measures have now been introduced, and a re-assessment will be undertaken in due course

The JAK inhibitor tofacitinib suppresses synovial JAK1-STAT signalling in rheumatoid arthritis.

ObjectiveTofacitinib is an oral Janus kinase (JAK) inhibitor for the treatment of rheumatoid arthritis (RA). The pathways affected by tofacitinib and the effects on gene expression in situ are unknown. Therefore, tofacitinib effects on synovial pathobiology were investigated.MethodsA randomised, double-blind, phase II serial synovial biopsy study (A3921073; NCT00976599) in patients with RA with an inadequate methotrexate response. Patients on background methotrexate received tofacitinib 10 mg twice daily or placebo for 28 days. Synovial biopsies were performed on Days -7 and 28 and analysed by immunoassay or quantitative PCR. Clinical response was determined by disease activity score and European League Against Rheumatism (EULAR) response on Day 28 in A3921073, and at Month 3 in a long-term extension study (A3921024; NCT00413699).ResultsTofacitinib exposure led to EULAR moderate to good responses (11/14 patients), while placebo was ineffective (1/14 patients) on Day 28. Tofacitinib treatment significantly reduced synovial mRNA expression of matrix metalloproteinase (MMP)-1 and MMP-3 (p&lt;0.05) and chemokines CCL2, CXCL10 and CXCL13 (p&lt;0.05). No overall changes were observed in synovial inflammation score or the presence of T cells, B cells or macrophages. Changes in synovial phosphorylation of signal transducer and activator of transcription 1 (STAT1) and STAT3 strongly correlated with 4-month clinical responses (p&lt;0.002). Tofacitinib significantly decreased plasma CXCL10 (p&lt;0.005) at Day 28 compared with placebo.ConclusionsTofacitinib reduces metalloproteinase and interferon-regulated gene expression in rheumatoid synovium, and clinical improvement correlates with reductions in STAT1 and STAT3 phosphorylation. JAK1-mediated interferon and interleukin-6 signalling likely play a key role in the synovial response.Trial registration numberNCT00976599

Possible large-N fixed-points and naturalness for O(N) scalar fields

We try to use scale-invariance and the large-N limit to find a non-trivial 4d O(N) scalar field model with controlled UV behavior and naturally light scalar excitations. The principle is to fix interactions by requiring the effective action for space-time dependent background fields to be finite and scale-invariant when regulators are removed. We find a line of non-trivial UV fixed-points in the large-N limit, parameterized by a dimensionless coupling. They reduce to classical la phi^4 theory when hbar -> 0. For hbar non-zero, neither action nor measure is scale-invariant, but the effective action is. Scale invariance makes it natural to set a mass deformation to zero. The model has phases where O(N) invariance is unbroken or spontaneously broken. Masses of the lightest excitations above the unbroken vacuum are found. We derive a non-linear equation for oscillations about the broken vacuum. The interaction potential is shown to have a locality property at large-N. In 3d, our construction reduces to the line of large-N fixed-points in |phi|^6 theory.Comment: 23 page

<SUP>187</SUP>Re-<SUP>187</SUP>Os in Lesser Himalayan sediments: measurement techniques and preliminary results

The applications of the 187Re-187Os isotope pair as a petrogenetic and geologic tracer are increasing in recent years due to several advances in the chemical extraction and purification of Re and Os, occurring at ppb levels in environmental samples, and in the precise determination of the Os isotope composition. We have established in our laboratory; based on available methods, chemical procedures and Negative Thermal Ionisation Mass Spectrometric techniques for the measurement of Re-Os concentrations in environmental samples and the Os isotope composition in them. Using these techniques, we are able to determine187Os/186Os ratios with a precision of ~1% (&#177;2&#963;&#956;; twice the standard error of the mean) in several tens of picogram of Os. Preliminary analysis of black shales from the Lower Tal section of the Maldeota phosphorite mine yields a mean187Re-187Os model age of 597 &#177; 30 Ma. The 187Os/186Os and Os concentration in black shales of the Lesser Himalaya range from 8 to 96 and 0.02 to 13 ng g-1 respectively. The mean 187Os/186Os in these samples is ~ 25, significantly higher than the crustal value of ~ 10.5, suggesting that these black shales could be an important source of radiogenic Os to the rivers draining the Himalaya and to the steady increase in 187Os/186Os of the oceans through the Cenozoic

<SUP>14</SUP>C in air over the Arabian Sea

Global monitoring of radiocarbon in atmospheric CO2 began during the mid fifties to determine the time scales of exchange of radiocarbon (and CO2) between the atmosphere and other terrestrial reservoirs. The distribution of natural radiocarbon in the environment was perturbed significantly during the 1960s through injection of 14C from nuclear weapon tests. This 'bomb 14C has proved to be an excellent tracer to characterize and quantify CO2 exchange between various reservoirs. We have measured radiocarbon activity of marine air over the central and eastern Arabian sea during 1993-95. The mean A 14C values are 121 ±6, 116 ±6 and 105±5%o respectively for these three years. These values, in conjunction with those reported in the literature for troposphere for the decades of 60s through 80s, show that the 14C activity in the tropospheric air has been decreasing exponentially with an e-folding time of -16 years

Schwinger-Dyson operators as invariant vector fields on a matrix-model analogue of the group of loops

For a class of large-N multi-matrix models, we identify a group G that plays the same role as the group of loops on space-time does for Yang-Mills theory. G is the spectrum of a commutative shuffle-deconcatenation Hopf algebra that we associate to correlations. G is the exponential of the free Lie algebra. The generating series of correlations is a function on G and satisfies quadratic equations in convolution. These factorized Schwinger-Dyson or loop equations involve a collection of Schwinger-Dyson operators, which are shown to be right-invariant vector fields on G, one for each linearly independent primitive of the Hopf algebra. A large class of formal matrix models satisfying these properties are identified, including as special cases, the zero momentum limits of the Gaussian, Chern-Simons and Yang-Mills field theories. Moreover, the Schwinger-Dyson operators of the continuum Yang-Mills action are shown to be right-invariant derivations of the shuffle-deconcatenation Hopf algebra generated by sources labeled by position and polarization.Comment: 24 page