855 research outputs found
Post-Polio Syndrome -- 1982-1991 -- Correspondence, Polio -- letter, 1985-06-27
No full textLetter from Halstead, Lauro S. to Sabin, Albert B. dated 1985-06-27.Sabin Collection Fair Use Policy</a
Members of the Halstead Saddle Club
No full textThis black and white photograph features the Halstead Saddle Club Overnight Campout at Yentruoc Lake southeast of Newton. Nine men, one woman, and five children are gathered around tables arranged near a supply wagon with a tarp covering. Halstead Saddle Club is printed on the tarp. Two of the men appear to be preparing food on small stoves on the tables. Names written on the front of the photo are: Jerry, Ralph, Ken, Ed D., Marly B., Hazel, Om, Ken B., Bill S., Leroy, Bus W., me [Carol Ewy].https://scholars.fhsu.edu/harvey/1032/thumbnail.jp
Long-term starvation and ageing induce AGE-1/PI 3-kinase-dependent translocation of DAF-16/FOXO to the cytoplasm
No full textBackground
The provision of stress resistance diverts resources from development and reproduction and must therefore be tightly regulated. In Caenorhabditis elegans, the switch to increased stress resistance to promote survival through periods of starvation is regulated by the DAF-16/FOXO transcription factor. Reduction-of-function mutations in AGE-1, the C. elegans Class IA phosphoinositide 3-kinase (PI3K), increase lifespan and stress resistance in a daf-16 dependent manner. Class IA PI3Ks downregulate FOXOs by inducing their translocation to the cytoplasm. However, the circumstances under which AGE-1 is normally activated are unclear. To address this question we used C. elegans first stage larvae (L1s), which when starved enter a developmentally-arrested diapause stage until food is encountered.
Results
We find that in L1s both starvation and daf-16 are necessary to confer resistance to oxidative stress in the form of hydrogen peroxide. Accordingly, DAF-16 is localised to cell nuclei after short-term starvation. However, after long-term starvation, DAF-16 unexpectedly translocates to the cytoplasm. This translocation requires functional age-1. H2O2 treatment can replicate the translocation and induce generation of the AGE-1 product PIP3. Because feeding reduces to zero in ageing adult C. elegans, these animals may also undergo long-term starvation. Consistent with our observation in L1s, DAF-16 also translocates to the cytoplasm in old adult worms in an age-1-dependent manner.
Conclusion
DAF-16 is activated in the starved L1 diapause. The translocation of DAF-16 to the cytoplasm after long-term starvation may be a feedback mechanism that prevents excessive expenditure on stress resistance. H2O2 is a candidate second messenger in this feedback mechanism. The lack of this response in age-1(hx546) mutants suggests a novel mechanism by which this mutation increases longevity
Maintaining the balance: teacher control and pupil disruptions in the classroom
No full textA class of 8-9 year-old children in England was observed for several months in order to explore their experiences of everyday schooling and especially the way they themselves understand these experiences. The research focused particularly on the way they experience and understand non-educational classroom activities like rituals and routines, classroom management and control, rewards and punishments. It highlighted the differences between the perceptions of the children and those of adults. One finding was that in the primary classroom children are under constant surveillance and control by the teacher, and that they may respond in a variety of ways. Sometimes they apparently accept the teacher’s discipline and authority, but other times they appear to subvert the teacher’s regulations and order through minor distractions, disruptions, attention-seeking and time-wasting activities. In the specific research described in this paper the focus of attention was on the informal learning that goes on in the hidden curriculum as a result of these classroom routines and subversions, especially in the domain of values and attitudes. A variety of research methods was used to gather data, including small group interviews, informal conversations and group activities as well as observation. Relevant adults were also interviewed, especially the class-teacher himself, but the main focus of the research was always on the children’s own perceptions. The findings, which are rich in their implications for teacher training, show that in the children’s subversion of the teacher’s authority there is a fine balance of power between them and the teacher. Even more importantly, they indicate that the pupils are consciously reflecting on and learning from their own behaviour and experiences and are thus taking the first steps towards becoming morally autonomous individual
Challenges in the Interpretation of Dengue Vaccine Trial Results
No full text<p>Challenges in the Interpretation of Dengue Vaccine Trial Results</p
Dengue virus activates polyreactive, natural IgG B cells after primary and secondary infection.
No full textBACKGROUND: Dengue virus is transmitted by mosquitoes and has four serotypes. Cross-protection to other serotypes lasting for a few months is observed following infection with one serotype. There is evidence that low-affinity T and/or B cells from primary infections contribute to the severe syndromes often associated with secondary dengue infections. such pronounced immune-mediated enhancement suggests a dengue-specific pattern of immune cell activation. This study investigates the acute and early convalescent B cell response leading to the generation of cross-reactive and neutralizing antibodies following dengue infection. METHODOLOGY/PRINCIPAL FINDINGS: We assayed blood samples taken from dengue patients with primary or secondary infection during acute disease and convalescence and compared them to samples from patients presenting with non-dengue related fever. Dengue induced massive early plasmablast formation, which correlated with the appearance of polyclonal, cross-reactive IgG for both primary and secondary infection. Surprisingly, the contribution of IgG to the neutralizing titer 4-7 days after fever onset was more than 50% even after primary infection. CONCLUSIONS/SIGNIFICANCE: Poly-reactive and virus serotype cross-reactive IgG are an important component of the innate response in humans during both primary and secondary dengue infection, and "innate specificities" seem to constitute part of the adaptive response in dengue. While of potential importance for protection during secondary infection, cross-reactive B cells will also compete with highly neutralizing B cells and possibly interfere with their development
Silvaninae Kirby 1837
No full textSUBFAMILY SILVANINAE Silvanus proximus Grouvelle 1904: 183; Halstead 1973: 61, 1993: 182; Thomas 1993: 25. = Silvanus planatus Germar 1824: 466; Fleutiaux and Sallé 1890: 390; Blackwelder 1944-1957: 420; Halstead 1973: 64 of Guadeloupe; likely a misidentification of S. proximus. = Silvanus unidentatus Olivier 1790: 9; Champion 1898: 405 of Grenada?; Blackwelder 1944-1957: 421 of Grenada?; Halstead 1973: 65; likely a misidentification. Distribution. Grenada, Guadeloupe, Martinique, St. Thomas; from Mexico to Brazil; introduced to Neotropics, native to and widespread in Africa; introduced to Lesser Antilles. Notes. Occasionally in stored products; also at lights and in forest litter.Published as part of Peck, Stewart B., 2011, The beetles of Martinique, Lesser Antilles (Insecta: Coleoptera); diversity and distributions, pp. 1-57 in Insecta Mundi 2011 (178) on page 25, DOI: 10.5281/zenodo.516101
Reconstructing Curved Surfaces From Specular. . .
No full text1 INTRODUCTION CR Categories: Keywords: Mark A. Halstead Brian A. Barsky Stanley A. Klein Robert B. Mandell University of California at Berkeley Reconstructing Curved Surfaces From Specular Reflection Patterns Using Spline Surface Fitting of Normals Apple Computer, 1 Infinite Loop M/S 301-3J, Cupertino, CA 95014. Computer Science Division, University of California, Berkeley, CA 94720-1776. www.cs.berkeley.edu/projects/optical/ School of Optometry, University of California, Berkeley, CA 94720-2020. We present an algorithm that reconstructs a threedimensional surface model from an image. The image is generated by illuminating a specularly reflective surface with a pattern of light. We discuss the application of this algorithm to an important problem in biomedicine, namely the measurement of the human cornea, although the algorithm is also applicable elsewhere. The distinction between this reconstruction technique and more traditional techniques that use light patterns is that the ima..
Prophylactic platelets in dengue: survey responses highlight lack of an evidence base.
No full textDengue is the most important arboviral infection of humans. Thrombocytopenia is frequently observed in the course of infection and haemorrhage may occur in severe disease. The degree of thrombocytopenia correlates with the severity of infection, and may contribute to the risk of haemorrhage. As a result of this prophylactic platelet transfusions are sometimes advocated for the prevention of haemorrhage. There is currently no evidence to support this practice, and platelet transfusions are costly and sometimes harmful. We conducted a global survey to assess the different approaches to the use of platelets in dengue. Respondents were all physicians involved with the treatment of patients with dengue. Respondents were asked that their answers reflected what they would do if they were the treating physician. We received responses from 306 physicians from 20 different countries. The heterogeneity of the responses highlights the variation in clinical practice and lack of an evidence base in this area and underscores the importance of prospective clinical trials to address this key question in the clinical management of patients with dengue
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