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1.
Appl Opt ; 57(10): 2394-2413, 2018 Apr 01.
Article in English | MEDLINE | ID: mdl-29714221

ABSTRACT

We present an optimal-estimation-based retrieval framework, the microphysical aerosol properties from polarimetry (MAPP) algorithm, designed for simultaneous retrieval of aerosol microphysical properties and ocean color bio-optical parameters using multi-angular total and polarized radiances. Polarimetric measurements from the airborne NASA Research Scanning Polarimeter (RSP) were inverted by MAPP to produce atmosphere and ocean products. The RSP MAPP results are compared with co-incident lidar measurements made by the NASA High-Spectral-Resolution Lidar HSRL-1 and HSRL-2 instruments. Comparisons are made of the aerosol optical depth (AOD) at 355 and 532 nm, lidar column-averaged measurements of the aerosol lidar ratio and Ångstrøm exponent, and lidar ocean measurements of the particulate hemispherical backscatter coefficient and the diffuse attenuation coefficient. The measurements were collected during the 2012 Two-Column Aerosol Project (TCAP) campaign and the 2014 Ship-Aircraft Bio-Optical Research (SABOR) campaign. For the SABOR campaign, 73% RSP MAPP retrievals fall within ±0.04 AOD at 532 nm as measured by HSRL-1, with an R value of 0.933 and root-mean-square deviation of 0.0372. For the TCAP campaign, 53% of RSP MAPP retrievals are within 0.04 AOD as measured by HSRL-2, with an R value of 0.927 and root-mean-square deviation of 0.0673. Comparisons with HSRL-2 AOD at 355 nm during TCAP result in an R value of 0.959 and a root-mean-square deviation of 0.0694. The RSP retrievals using the MAPP optimal estimation framework represent a key milestone on the path to a combined lidar+polarimeter retrieval using both HSRL and RSP measurements.

2.
J Geophys Res Atmos ; 123(5): 2655-2683, 2018 Mar 16.
Article in English | MEDLINE | ID: mdl-33479573

ABSTRACT

We introduce the Clouds Above the United States and Errors at the Surface (CAUSES) project with its aim of better understanding the physical processes leading to warm screen temperature biases over the American Midwest in many numerical models. In this first of four companion papers, 11 different models, from nine institutes, perform a series of 5 day hindcasts, each initialized from reanalyses. After describing the common experimental protocol and detailing each model configuration, a gridded temperature data set is derived from observations and used to show that all the models have a warm bias over parts of the Midwest. Additionally, a strong diurnal cycle in the screen temperature bias is found in most models. In some models the bias is largest around midday, while in others it is largest during the night. At the Department of Energy Atmospheric Radiation Measurement Southern Great Plains (SGP) site, the model biases are shown to extend several kilometers into the atmosphere. Finally, to provide context for the companion papers, in which observations from the SGP site are used to evaluate the different processes contributing to errors there, it is shown that there are numerous locations across the Midwest where the diurnal cycle of the error is highly correlated with the diurnal cycle of the error at SGP. This suggests that conclusions drawn from detailed evaluation of models using instruments located at SGP will be representative of errors that are prevalent over a larger spatial scale.

3.
BMC Infect Dis ; 17(1): 624, 2017 09 16.
Article in English | MEDLINE | ID: mdl-28915795

ABSTRACT

BACKGROUND: Hepatitis C (HCV) infection causes an asymptomatic chronic hepatitis in most affected individuals, which often remains undetected until cirrhosis and cirrhosis-related complications occur. Screening of high-risk subjects in Northern Norway has revealed a relatively low prevalence in the general population (0.24%). Despite this, late complications of HCV infection are increasing. Our object was to estimate the future prevalence and complications of chronic HCV infection in the period 2013-2050 in a low-risk area. METHODS: We have entered available data into a prognostic Markov model to project future complications to HCV infection. RESULTS: The model extrapolates the prevalence in the present cohort of HCV-infected individuals, and assumes a stable low incidence in the projection period. We predict an almost three-fold increase in the incidence of cirrhosis (68 per 100,000), of decompensated cirrhosis (21 per 100,000) and of hepatocellular carcinoma (4 per 100,000) by 2050, as well as a six-fold increase in the cumulated number of deaths from HCV-related liver disease (170 per 100,000 inhabitants). All estimates are made assuming an unchanged treatment coverage of approximately 15%. The estimated numbers can be reduced by approximately 50% for cirrhosis, and by approximately one third for the other endpoints if treatment coverage is raised to 50%. CONCLUSION: These projections from a low-prevalence area indicate a substantial rise in HCV-related morbidity and mortality in the coming years. The global HCV epidemic is of great concern and increased treatment coverage is necessary to reduce the burden of the disease.


Subject(s)
Hepatitis C, Chronic/complications , Hepatitis C, Chronic/epidemiology , Carcinoma, Hepatocellular/epidemiology , Carcinoma, Hepatocellular/virology , Cohort Studies , Humans , Incidence , Liver Cirrhosis/epidemiology , Liver Neoplasms/epidemiology , Liver Neoplasms/virology , Markov Chains , Models, Theoretical , Norway/epidemiology , Prevalence , Prognosis
4.
Neuroscience ; 230: 139-50, 2013 Jan 29.
Article in English | MEDLINE | ID: mdl-23159309

ABSTRACT

The N-methyl-D-aspartate (NMDA) type of glutamate receptors is involved in synaptic plasticity in hippocampal mossy fibre-CA3 pyramidal neuron synapses. The ultrastructural localization of NMDA receptor subunits at this synapse type is not known. By postembedding electron microscopic immunogold cytochemistry we show that the NMDA receptor subunits GluN1, GluN2A, GluN2B, GluN2C and GluN2D are located in postsynaptic membranes of mossy fibre as well as CA3 recurrent associational commissural synapses. In the mossy fibres the GluN1, GluN2B and GluN2D labelling patterns suggested that these subunits were located also presynaptically in nerve terminal membranes and in mossy fibre axons. GluN3B was predominantly present in mossy fibre synapses as compared to recurrent associational commissural synapses, showing a presynaptic labelling pattern. In conclusion, while the postsynaptic localization of GluN1, GluN2A, GluN2B, and GluN2D is in good agreement with the recent finding of NMDA receptor-dependent long term potentiation (LTP) at CA3 mossy fibre synapses, we propose that presynaptic GluN1, GluN2B, GluN2D and GluN3B subunits could be involved in plastic phenomena such as certain types of LTP and recurrent mossy fibre growth.


Subject(s)
Hippocampus/cytology , Mossy Fibers, Hippocampal/ultrastructure , Post-Synaptic Density/metabolism , Presynaptic Terminals/metabolism , Protein Subunits/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , Animals , Hippocampus/metabolism , Immunohistochemistry , Male , Microscopy, Immunoelectron , Mossy Fibers, Hippocampal/metabolism , Post-Synaptic Density/ultrastructure , Presynaptic Terminals/ultrastructure , Rats , Rats, Wistar , Receptors, N-Methyl-D-Aspartate/ultrastructure
5.
Mech Dev ; 100(2): 251-62, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11165482

ABSTRACT

Smad6 and Smad7 comprise a subclass of vertebrate Smads that antagonize, rather than transduce, TGF-beta family signaling. These Anti-Smads can block BMP signaling, as evidenced by their ability to induce a secondary dorsal axis when misexpressed ventrally in Xenopus embryos. Smad7 inhibits additional TGF-beta related pathways, and causes spina bifida when misexpressed dorsally. We have performed structure-function analyses to identify domains of Anti-Smads that are responsible for their shared and unique activities. We find that the C-terminal domain of Smad7 displays strong axis inducing activity but cannot induce spina bifida. The isolated N-terminal domain of Smad7 is inactive but restores the ability of the C-terminus to cause spina bifida when the two are co-expressed. By contrast, the N- and C-terminal domains of Smad6 have weak axis inducing activity when expressed individually, but show full activity when co-expressed. Chimeric analysis demonstrates that the C-terminal domain of Smad7, but not Smad6, can induce spina bifida when fused to the N-terminal domain of either Smad6 or Smad7. Thus, although the C-terminal domain is the primary determinant of the intrinsic activity of Xenopus Anti-Smads, the N-terminal domain is essential for full activity, is interchangeable between Smad6 and 7, and can function in trans.


Subject(s)
DNA-Binding Proteins/chemistry , DNA-Binding Proteins/physiology , Trans-Activators/chemistry , Trans-Activators/physiology , Animals , Blotting, Western , Bone Morphogenetic Proteins/metabolism , DNA-Binding Proteins/genetics , Gene Deletion , Models, Genetic , Mutation , Phenotype , Plasmids/metabolism , Protein Structure, Tertiary , RNA/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , Smad6 Protein , Smad7 Protein , Spinal Dysraphism/metabolism , Structure-Activity Relationship , Time Factors , Trans-Activators/genetics , Xenopus , Xenopus Proteins
6.
Genes Cells ; 3(6): 387-94, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9734784

ABSTRACT

BACKGROUND: Bone morphogenetic proteins (BMPs) transmit signals via the intracellular protein Smad1, which is phosphorylated by ligand bound receptors, translocates to the nucleus, and functions to activate BMP target genes. Recently, a subclass of Smad proteins has been shown to inhibit, rather than transduce, BMP signalling, either by binding to the intracellular domain of BMP receptors, thereby preventing phosphorylation-mediated activation of Smad1, or by binding directly to Smad1, thereby inhibiting its ability to activate gene transcription. RESULTS: We have identified a Xenopus Smad (Smad6) that is 52% identical to mammalian Smad6, an inhibitory Smad. The spatial pattern of expression of Smad6 changes dynamically during embryogenesis and is similar to that of BMP-4 at the tailbud stage. Overexpression of Smad6 in Xenopus embryos phenocopies the effect of blocking BMP-4 signalling, leading to dorsalization of mesoderm and neuralization of ectoderm. Xenopus Smad6 completely blocks the activity of exogenous BMP-4, and, unlike human Smad6, partially blocks the activity of activin, in a mesoderm induction assay. We also find that Smad6 protein accumulates at the membrane in some cells but is partially or completely restricted to nuclei of most overexpressing cells. CONCLUSIONS: We have identified an inhibitory Xenopus Smad, Smad6, that functions as an intracellular antagonist of activin and BMP-4 signalling. Our finding that Smad6 protein is partially or completely restricted to nuclei of most overexpressing cells suggests that it may employ a novel or additional mechanism of action to antagonize TGF-beta family signalling other than that reported for other inhibitory Smads.


Subject(s)
DNA-Binding Proteins/physiology , Trans-Activators/physiology , Transforming Growth Factor beta/antagonists & inhibitors , Xenopus/embryology , Xenopus/genetics , Activins , Amino Acid Sequence , Animals , Body Patterning/physiology , Bone Morphogenetic Protein 4 , Bone Morphogenetic Proteins/pharmacology , Cloning, Molecular , DNA, Complementary/chemistry , DNA, Complementary/genetics , DNA-Binding Proteins/analysis , DNA-Binding Proteins/genetics , Embryo, Nonmammalian/chemistry , Embryonic Induction/drug effects , Embryonic Induction/genetics , Embryonic Induction/physiology , Gene Expression , Gene Expression Regulation, Developmental , Immunohistochemistry , In Situ Hybridization , Inhibins/pharmacology , Mesoderm/drug effects , Mesoderm/physiology , Molecular Sequence Data , Nervous System/embryology , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Smad6 Protein , Trans-Activators/analysis , Trans-Activators/genetics , Xenopus Proteins
7.
Development ; 124(9): 1845-50, 1997 May.
Article in English | MEDLINE | ID: mdl-9165131

ABSTRACT

Cortical granules are secretory vesicles poised at the cortex of an egg that, upon stimulation by sperm contact at fertilization, secrete their contents. These contents modify the extracellular environment and block additional sperm from reaching the egg. The role of cortical granules in blocking polyspermy is conserved throughout much of phylogeny. In the sea urchin, cortical granules accumulate throughout the cytoplasm during oogenesis, but in mature eggs the cortical granules are attached to the plasma membrane, having translocated to the cortex at some earlier time. To study the process of cortical granule translocation to the cell surface we have devised a procedure for maturation of sea urchin oocytes in vitro. Using this procedure, we examined the rate of oocyte maturation by observing the movement and breakdown of the germinal vesicle, the formation of polar bodies and the formation of the egg pronucleus. We find that oocyte maturation takes approximately 9 hours in the species used here (Lytechinus variegatus), from the earliest indication of maturation (germinal vesicle movement) to formation of a distinct pronucleus. We then observed the translocation of cortical granules in these cells by immunolocalization using a monoclonal antibody to hyalin, a protein packaged specifically in cortical granules. We found that the translocation of cortical granules in in vitro-matured oocytes begins with the movement of the germinal vesicle to the oocyte cell surface, and is 50% complete 1 hour after germinal vesicle breakdown. In the in vitro-matured egg, 99% of the cortical granules are at the cortex, indistinguishable from translocation in oocytes that mature in vivo. We have also found that eggs that mature in vitro are functionally identical to eggs that mature in vivo by four criteria. (1) The matured cells undergo a selective turnover of mRNA encoding cortical granule contents. (2) The newly formed pronucleus begins transcription of histone messages. (3) Cortical granules that translocate in vitro are capable of exocytosis upon activation by the calcium ionophore, A23187. (4) The mature egg is fertilizable and undergoes normal cleavage and development. In vitro oocyte maturation enables us to examine the mechanism of cortical granule translocation and other processes that had previously only been observed in static sections of fixed ovaries.


Subject(s)
Cytoplasmic Granules/physiology , Oocytes/physiology , Sperm-Ovum Interactions/physiology , Animals , Cytoplasmic Granules/ultrastructure , Female , In Situ Hybridization , In Vitro Techniques , Kinetics , Male , Oocytes/ultrastructure , Phylogeny , RNA/analysis , RNA/biosynthesis , Sea Urchins , Spermatozoa/physiology , Time Factors
8.
Development ; 122(2): 703-13, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8625821

ABSTRACT

The extracellular matrix is important in the regulation of many cellular events of early development including migration, shape change, proliferation and gene expression. In the sea urchin embryo, disruption of the extracellular matrix results in selective defects in each of these events during gastrulation. Here we describe a new molecule of the extracellular matrix in Lytechinus variegatus, referred to as ECM 18, that has several important features. First, antibody interference of ECM 18 results in a profound but reversible inhibition of primary mesenchyme cell organization and endoderm morphogenesis during gastrulation. Second, during gastrulation, ECM 18 mRNA accumulates to highest levels in the invaginating endoderm and the ECM 18 protein deposited in the basal lamina surrounding the archenteron as well as in other areas of the blastocoel wall. Immunolocalization by fluorescence and electron microscopy demonstrates the selective accumulation of ECM 18 in the extracellular matrix. Third, although the mRNA encoding ECM 18 is present throughout development, the protein accumulates only during gastrulation. ECM 18 protein is not detected in eggs or early embryos and analysis of polysome-associated mRNA suggests that at least part of the translational regulation of ECM 18 is at the level of ECM 18 mRNA-polysome formation. Finally, sequence analysis of ECM 18 shows that the protein contains a repeat sequence with a conserved cysteine motif, suggestive of involvement in protein-protein interactions. Thus, ECM 18 appears to be important in mediating select morphogenetic changes during gastrulation and the pattern of its expression in the embryo is unique among the extracellular matrix molecules known in this embryo.


Subject(s)
Extracellular Matrix Proteins/biosynthesis , Extracellular Matrix/metabolism , Gastrula/physiology , Gene Expression Regulation , Mesoderm/physiology , Sea Urchins/embryology , Amino Acid Sequence , Animals , Antibodies , Blotting, Western , DNA, Complementary , Embryo, Nonmammalian/cytology , Embryo, Nonmammalian/physiology , Extracellular Matrix Proteins/analysis , Extracellular Matrix Proteins/physiology , Fluorescent Antibody Technique , Gastrula/cytology , Gene Library , In Situ Hybridization , Mesoderm/cytology , Molecular Sequence Data , Sequence Homology, Amino Acid
9.
Community Ment Health J ; 11(3): 239-48, 1975.
Article in English | MEDLINE | ID: mdl-1183150

ABSTRACT

This paper reports a study of the extent to which essential elements of community mental health are part of mental health agencies' practices. A sample of 263 social workers reported on the nature of programming and services of 19 mental health facilities ranging from city and state community mental health centers to inpatient psychiatric hospitals. All agencies were found to be engaged primarily in diagnosis and treatment, and such community mental health components as primary prevention, coordination, continuity of care, and use of community boards were virtually nonexistent. Possible explanations and implications of these findings are discussed.


Subject(s)
Community Mental Health Services , Delivery of Health Care/standards , Quality of Health Care , Role , Social Work, Psychiatric/standards
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