913 resultados para Mount Auburn Cemetery (Watertown and Cambridge, Mass.)


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Iodine-129 (Full-size image (<1 K)) concentrations have been determined by accelerator mass spectrometry in rainwater samples taken at Seville (southwestern Spain) in 1996 and 1997. This technique allows a reduction in the detection limits for this radionuclide in comparison to radiometric counting and other mass spectrometric methods such as ICP-MS. Typical 129I concentrations range from 4.7×107129I atoms/l (19.2%) to 4.97×109129I atoms/l (5.9%), while 129I depositions are normally in the order of 108–1010 atoms/m2 d. These values agree well with other results obtained for recent rainwater samples collected in Europe. Apart from these, the relationship between 129I deposition and some atmospheric factors has been analyzed, showing the importance of the precipitation rate and the concentration of suspended matter in it.

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The focus of this thesis lies in the development of a sensitive method for the analysis of protein primary structure which can be easily used to confirm the DNA sequence of a protein's gene and determine the modifications which are made after translation. This technique involves the use of dipeptidyl aminopeptidase (DAP) and dipeptidyl carboxypeptidase (DCP) to hydrolyze the protein and the mass spectrometric analysis of the dipeptide products.^ Dipeptidyl carboxypeptidase was purified from human lung tissue and characterized with respect to its proteolytic activity. The results showed that the enzyme has a relatively unrestricted specificity, making it useful for the analysis of the C-terminal of proteins. Most of the dipeptide products were identified using gas chromatography/mass spectrometry (GC/MS). In order to analyze the peptides not hydrolyzed by DCP and DAP, as well as the dipeptides not identified by GC/MS, a FAB ion source was installed on a quadrupole mass spectrometer and its performance evaluated with a variety of compounds.^ Using these techniques, the sequences of the N-terminal and C-terminal regions and seven fragments of bacteriophage P22 tail protein have been verified. All of the dipeptides identified in these analysis were in the same DNA reading frame, thus ruling out the possibility of a single base being inserted or deleted from the DNA sequence. The verification of small sequences throughout the protein sequence also indicates that no large portions of the protein have been removed after translation. ^

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Two sets of mass spectrometry-based methods were developed specifically for the in vivo study of extracellular neuropeptide biochemistry. First, an integrated micro-concentration/desalting/matrix-addition device was constructed for matrix-assisted laser desorption ionization mass spectrometry (MALDI MS) to achieve attomole sensitivity for microdialysis samples. Second, capillary electrophoresis (CE) was incorporated into the above micro-liquid chromatography (LC) and MALDI MS system to provide two-dimensional separation and identification (i.e. electrophoretic mobility and molecular mass) for the analysis of complex mixtures. The latter technique includes two parts of instrumentation: (1) the coupling of a preconcentration LC column to the inlet of a CE capillary, and (2) the utilization of a matrix-precoated membrane target for continuous CE effluent deposition and for automatic MALDI MS analysis (imaging) of the CE track.^ Initial in vivo data reveals a carboxypeptidase A (CPA) activity in rat brain involved in extracellular neurotensin metabolism. Benzylsuccinic acid, a CPA inhibitor, inhibited neurotensin metabolite NT1-12 formation by 70%, while inhibitors of other major extracellular peptide metabolizing enzymes increased NT1-12 formation. CPA activity has not been observed in previous in vitro experiments. Next, the validity of the methodology was demonstrated in the detection and structural elucidation of an endogenous neuropeptide, (L)VV-hemorphin-7, in rat brain upon ATP stimulation. Finally, the combined micro-LC/CE/MALDI MS was used in the in vivo metabolic study of peptide E, a mu-selective opioid peptide with 25 amino acid residues. Profiles of 88 metabolites were obtained, their identity being determined by their mass-to-charge ratio and electrophoretic mobility. The results indicate that there are several primary cleavage sites in vivo for peptide E in the release of its enkephalin-containing fragments. ^

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The mass budget of the ice caps surrounding the Antarctica Peninsula and, in particular, the partitioning of its main components are poorly known. Here we approximate frontal ablation (i.e. the sum of mass losses by calving and submarine melt) and surface mass balance of the ice cap of Livingston Island, the second largest island in the South Shetland Islands archipelago, and analyse variations in surface velocity for the period 2007–2011. Velocities are obtained from feature tracking using 25 PALSAR-1 images, and used in conjunction with estimates of glacier ice thicknesses inferred from principles of glacier dynamics and ground-penetrating radar observations to estimate frontal ablation rates by a flux-gate approach. Glacier-wide surface mass-balance rates are approximated from in situ observations on two glaciers of the ice cap. Within the limitations of the large uncertainties mostly due to unknown ice thicknesses at the flux gates, we find that frontal ablation (−509 ± 263 Mt yr−1, equivalent to −0.73 ± 0.38 m w.e. yr−1 over the ice cap area of 697 km2) and surface ablation (−0.73 ± 0.10 m w.e. yr−1) contribute similar shares to total ablation (−1.46 ± 0.39 m w.e. yr−1). Total mass change (δM = −0.67 ± 0.40 m w.e. yr−1) is negative despite a slightly positive surface mass balance (0.06 ± 0.14 m w.e. yr−1). We find large interannual and, for some basins, pronounced seasonal variations in surface velocities at the flux gates, with higher velocities in summer than in winter. Associated variations in frontal ablation (of ~237 Mt yr−1; −0.34 m w.e. yr−1) highlight the importance of taking into account the seasonality in ice velocities when computing frontal ablation with a flux-gate approach.

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We report near-infrared radial velocity (RV) measurements of the recently identified donor star in the high mass X-ray binary (HMXB) system OAO 1657−415 obtained in the H band using ISAAC on the Very Large Telescope. Cross-correlation methods were employed to construct a RV curve with a semi-amplitude of 22.1 ± 3.5 km s−1. Combined with other measured parameters of this system it provides a dynamically determined neutron star (NS) mass of 1.42 ± 0.26 M⊙ and a mass of 14.3 ± 0.8 M⊙ for the Ofpe/WN9 highly evolved donor star. OAO 1657−415 is an eclipsing HMXB pulsar with the largest eccentricity and orbital period of any within its class. Of the 10 known eclipsing X-ray binary pulsars OAO 1657−415 becomes the ninth with a dynamically determined NS mass solution and only the second in an eccentric system. Furthermore, the donor star in OAO 1657−415 is much more highly evolved than the majority of the supergiant donors in other HMXBs, joining a small but growing list of HMXBs donors with extensive hydrogen depleted atmospheres. Considering the evolutionary development of OAO 1657−415, we have estimated the binding energy of the envelope of the mass donor and find that there is insufficient energy for the removal of the donor’s envelope via spiral-in, ruling out a common envelope evolutionary scenario. With its non-zero eccentricity and relatively large orbital period the identification of a definitive evolutionary pathway for OAO 1657−415 remains problematic, we conclude by proposing two scenarios which may account for OAO 1657−415 current orbital configuration.

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A conditioning procedure is proposed allowing to install into the concrete specimens any selected value of water saturation degree with homogeneous moisture distribution. This is achieved within the least time and the minimum alteration of the concrete specimens. The protocol has the following steps: obtaining basic drying data at 50 °C (water absorption capacity and drying curves); unidirectional drying of the specimens at 50 °C until reaching the target saturation degree values; redistribution phase in closed containers at 50 °C (with measurement of the quasi-equilibrium relative humidities); storage into controlled environment chambers until and during mass transport tests, if necessary. A water transport model is used to derive transport parameters of the tested materials from the drying data, i.e., relative permeabilities and apparent water diffusion coefficients. The model also allows calculating moisture profiles during isothermal drying and redistribution phases, thus allowing optimization of the redistribution times for obtaining homogeneous moisture distributions.

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v.8:no.2 (1883)

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v.25:no.1 (1901)

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no.1 (1865)

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no.8, pts.1-2 (1874-1875)

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Records of cases heard in the Massachusetts Court of Common Pleas (Middlesex Co.) in Cambridge, Mass., and the New Hampshire Inferior Court of Common Pleas (Hillsborough Co.) in Amherst, N.H and matters brought before justices of the peace. Records identify the litigants, with some notes on fees and settlements; many of the cases concern debts. Justices of the peace include: Israel Atherton (Lancaster, Mass.); Samuel Dana (Amherst, N.H.); Joshua Longley (Shirley, Mass.); Nathaniel Paine (Worcester, Mass.); James Prescott (Westford, Mass.); Jeremiah Stiles (Keene, N.H.); William Swan (Groton, Mass.); Sampson Tuttle (Littleton, Mass.); and Henry Woods (Pepperell, Mass.).

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In this deed of feoffment, written on Dec. 10, 1677, Thomas Sweetman agreed to sell his dwelling house, barn, and orchard to his son-in-law, Michael Spencer, for the cost of eighty pounds sterling. The property was located in Cambridge, Massachusetts, on what was then the northwest corner of the grounds of Harvard College, and was sold "together with the wood lot upon the rocks and cow commons belonging to it." The deed specifies that both Sweetman and his wife Isabel were to be allowed to occupy the property until their deaths, and further explains that Spencer and his family were already living in the dwelling house, occupying three rooms. The document was signed, sealed, and delivered in the presence of Daniel Gookin, Jr. and John Bridgham. It was also signed by Thomas Sweetman.

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Contains notes taken by Harvard student Lyman Spalding during eleven chemistry lectures delivered by Harvard Professor Aaron Dexter (1750-1829) in the fall of 1795 and recipes prepared and used by Spalding in his medical practice in 1797. The recipes include elixir vitriol, containing liquor, Jamaica pepper, cinnamon, and ginger, and an electuary for a cough, containing oxymel squills (sea onion in honey), licorice, antimonium tartaricum potash (a compound of the chemical element antimony and a potassium-containing salt), and opium. The volume also contains writings about chemistry by Spalding, some of which appear transcribed from published sources, in undated entries, and a diary entry from 1799 regarding an experiment with water.