323,809 research outputs found
Antheridial dehiscence in ferns
No full textWe investigated the mechanism of antheridial dehiscence in ferns for the first time using fluorescence microscopy as well as scanning and transmission electron microscopy. The mechanism leading to antheridial dehiscence in Polystichum setiferum, Asplenium trichomanes and A. onopteris was found to depend on the different cellulose contents of the inner and outer walls of the ring cells detected with calcofluor white stain and the Thie ́ry test. The extremely low cellulose content of the ring cell walls facing spermatozoids made them less mechanically resilient than external wall cells. When the ring cells absorbed water they expanded only into the antheridial cavity, pushing the gametes against the cap cell, which detached from the ring cell below and enabled spermatozoid release. The newly released spermatozoids were spherical bodies covered in cellulose fibrils. The significance of cellulose fibrils could be to isolate the gametes from each other, to reinforce the electron transparent material and to protect the gamete from pressure created by the ring cells during release
Orbitofrontal Cortex Abnormalities in Schizophrenia
No full textThe magnetic resonance imaging studies investigating the volumes of the orbitofrontal cortex in patients suffering from schizophrenia are here presented, trying to elucidate its role for the pathophysiology and for the cognition of the disease
What rationale for treatment of occupational interstitial lung diseases with the drugs approved for idiopathic pulmonary fibrosis?
No full textPurpose of review To critically discuss the rationale for the use of drugs approved for idiopathic pulmonary fibrosis (IPF) to treat occupational interstitial lung diseases (OILDs). Recent findings Although IPF and OILDs share several clinical, radiological and probably pathogenetic features, currently, OILDs do not have a standard of care. In recent years, our knowledge and understanding of ILDs has improved substantially. Recently, the progressive pulmonary fibrosis (PPF) phenotype, which refers to non-IPF fibrotic ILDs that progress despite appropriate treatment, has been defined. OILDs may also be progressive. Nintedanib, initially approved for treatment of IPF, is also approved in patients with PPF. On the other hand, pirfenidone is approved in IPF but not in PPF, due to the lack of robust evidence of efficacy in this patient subset. Summary OILDs are a large and highly heterogeneous group of conditions without a proper standard of care. Nintedanib may slow functional decline and disease progression in progressive OILDs, and new clinical trials are ongoing
Protein Characterization of Protein Bodies from Cotyledons of Mucuna pruriens (L.) DC
No full textSeeds of Mucuna pruriens (L.) DC. (Fabaceae) were analyzed for protein composition of protein bodies isolated from cotyledons. Protein bodies were successfully separated by Lympholyte and those of dry seeds, observed by scanning electron microscope, were elliptical or spherical in shape with a diameter of 5-12 μm. Protein content in dry seed protein bodies was 10.6 mg/g dry weight. Globulin was the largest protein fraction isolated (62.5 %), followed by albumin (18.3 %), glutelin (15.8 %) and prolamin (3.4 %). The prolamin fraction and high glutelin content are uncommon in legumes. SDS-PAGE of albumins, globulins, prolamins and glutelins provided different band numbers and molecular weights under reducing and non reducing conditions and suggested that the albumin fraction is rich in disulphide bonds. © 2013 Springer Science+Business Media New York
Insights into the Larderello Geothermal Field: structural setting and distribution of thermal and 3He anomalies
No full textLynn S Chancer, Martín Sánchez-Jankowski and Christine Trost (eds), Youth, Jobs, and the Future: Problems and Prospects
No full textNowadays, the US labor market is characterized by the persistence of high youth unemployment. During the Great Recession, which in the United States covered the period 2007–2009, the unemployment rate rose to a peak of more than 25% for 16- to 19-year-olds and over 15% for 20- to 24-year-olds. Over the following decade, it remained significantly high – even if the overall unemployment rate dropped to the ‘natural level’ (about 5%)
Optical transmission spectra of a silicate glass containing nanocrystallites of cadmium sulphoselenide
No full textThe optical transmission spectra of CdSe x S 1-x doped low viscosity silicate glass are experimentally studied. Glass samples were subjected to one- or multi-step heat treatment for different lengths of time. We have followed the modification of the absorption spectra after each heat treatment. The red shift of the absorption edge and the accompanying change of coloration from orange to red are explained by size-quantization effects in the energy spectrum of electrons and holes in semiconductor nanoparticles thermally developed in low viscosity glass matrix. X-ray diffraction data show no stoichiometry changes during the heat treatment processes. Crystallites composition ( ) defined from the diffraction peaks was very close to the value estimated from the position of absorption edge. Copyright Springer-Verlag Berlin/Heidelberg 2003
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