335 research outputs found
Bioimaging using full field and contact EUV and SXR microscopes with nanometer spatial resolution
We present our recent results, related to nanoscale imaging in the extreme ultraviolet (EUV) and soft X-ray (SXR) spectral ranges and demonstrate three novel imaging systems recently developed for the purpose of obtaining high spatial resolution images of nanoscale objects with the EUV and SXR radiations. All the systems are based on laser-plasma EUV and SXR sources, employing a double stream gas puff target. The EUV and SXR full field microscopes—operating at 13.8 nm and 2.88 nm wavelengths, respectively—are currently capable of imaging nanostructures with a sub-50 nm spatial resolution with relatively short (seconds) exposure times. The third system is a SXR contact microscope, operating in the “water-window” spectral range (2.3–4.4 nm wavelength), to produce an imprint of the internal structure of the investigated object in a thin surface layer of SXR light sensitive poly(methyl methacrylate) photoresist. The development of such compact imaging systems is essential to the new research related to biological science, material science, and nanotechnology applications in the near future. Applications of all the microscopes for studies of biological samples including carcinoma cells, diatoms, and neurons are presented. Details about the sources, the microscopes, as well as the imaging results for various objects will be shown and discussed
Bioimaging using full field and contact EUV and SXR microscopes with nanometer spatial resolution
We present our recent results, related to nanoscale imaging in the extreme ultraviolet (EUV) and soft X-ray (SXR) spectral ranges and demonstrate three novel imaging systems recently developed for the purpose of obtaining high spatial resolution images of nanoscale objects with the EUV and SXR radiations. All the systems are based on laser-plasma EUV and SXR sources, employing a double stream gas puff target. The EUV and SXR full field microscopes-operating at 13.8 nm and 2.88 nm wavelengths, respectively-are currently capable of imaging nanostructures with a sub-50 nm spatial resolution with relatively short (seconds) exposure times. The third system is a SXR contact microscope, operating in the "water-window" spectral range (2.3-4.4 nm wavelength), to produce an imprint of the internal structure of the investigated object in a thin surface layer of SXR light sensitive poly(methyl methacrylate) photoresist. The development of such compact imaging systems is essential to the new research related to biological science, material science, and nanotechnology applications in the near future. Applications of all the microscopes for studies of biological samples including carcinoma cells, diatoms, and neurons are presented. Details about the sources, the microscopes, as well as the imaging results for various objects will be shown and discussed
Evaluation of gastrointestinal transit in clinical practice: position paper of the American and European Neurogastroenterology and Motility Societies
Disorders of gastrointestinal (GI) transit and motility are common, and cause either delayed or accelerated transit through the stomach, small intestine or colon, and affect one or more regions. Assessment of regional and/or whole gut transit times can provide direct measurements and diagnostic information to explain the cause of symptoms, and plan therapy.Recently, several newer diagnostic tools have become available. The American and European Neurogastroenterology and Motility Societies undertook this review to provide guidelines on the indications and optimal methods for the use of transit measurements in clinical practice. This was based on evidence of validation including performance characteristics, clinical significance, and strengths of various techniques. The tests include measurements of: gastric emptying with scintigraphy, wireless motility capsule, and 13 C breath tests; small bowel transit with breath tests, scintigraphy, and wireless motility capsule; and colonic transit with radioopaque markers, wireless motility capsule, and scintigraphy. Based on the evidence, consensus recommendations are provided for each technique and for the evaluations of regional and whole gut transit. In summary, tests of gastrointestinal transit are available and useful in the evaluation of patients with symptoms suggestive of gastrointestinal dysmotility, since they can provide objective diagnosis and a rational approach to patient management.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79321/1/j.1365-2982.2010.01612.x.pd
Factors related to abdominal pain in gastroparesis: contrast to patients with predominant nausea and vomiting
Background Factors associated with abdominal pain in gastroparesis are incompletely evaluated and comparisons of pain vs other symptoms are limited. This study related pain to clinical factors in gastroparesis and contrasted pain/discomfort‐ with nausea/vomiting‐predominant disease. Methods Clinical and scintigraphy data were compared in 393 patients from seven centers of the NIDDK Gastroparesis Clinical Research Consortium with moderate‐severe (Patient Assessment of Upper Gastrointestinal Disorders Symptoms [ PAGI ‐ SYM ] score ≥3) vs none‐mild ( PAGI ‐ SYM < 3) upper abdominal pain and predominant pain/discomfort vs nausea/vomiting. Key Results Upper abdominal pain was moderate‐severe in 261 (66%). Pain/discomfort was predominant in 81 (21%); nausea/vomiting was predominant in 172 (44%). Moderate‐severe pain was more prevalent with idiopathic gastroparesis and with lack of infectious prodrome (P ≤ 0.05) and correlated with scores for nausea/vomiting, bloating, lower abdominal pain/discomfort, bowel disturbances, and opiate and antiemetic use (P < 0.05), but not gastric emptying or diabetic neuropathy or control. Gastroparesis severity, quality of life, and depression and anxiety were worse with moderate‐severe pain (P ≤ 0.008). Factors associated with moderate‐severe pain were similar in diabetic and idiopathic gastroparesis. Compared to predominant nausea/vomiting, predominant pain/discomfort was associated with impaired quality of life, greater opiate, and less antiemetic use (P < 0.01), but similar severity and gastric retention. Conclusions & Inferences Moderate‐severe abdominal pain is prevalent in gastroparesis, impairs quality of life, and is associated with idiopathic etiology, lack of infectious prodrome, and opiate use. Pain is predominant in one fifth of gastroparetics. Predominant pain has at least as great an impact on disease severity and quality of life as predominant nausea/vomiting.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97520/1/nmo12091.pd
The Color of Childhood: The Role of the Child/Human Binary in the Production of Anti-Black Racism
The binary between the figure of the child and the fully human being is invoked with regularity in analyses of race, yet its centrality to the conception of race has never been fully explored. For most commentators, the figure of the child operates as a metaphoric or rhetorical trope, a non-essential strategic tool in the perpetuation of White supremacy. As I show in the following, the child/human binary does not present a contingent or merely rhetorical construction but, rather, a central feature of racialization. Where Black peoples are situated as objects of violence it is often precisely because Blackness has been identified with childhood and childhood is historically identified as the archetypal site of naturalized violence and servitude. I proceed by offering a historical account of how Black peoples came to inherit the subordination and dehumanization of European childhood and how White youth were subsequently spared through their partial categorization as adults
Making Space for Failure in Geographic Research
The idea that field research is an inherently “messy” process has become widely accepted by geographers in recent years. There has thus far been little acknowledgment, however, of the role that failure plays in doing human geography. In this article we push back against this, arguing that failure should be recognized as a central component of what it means to do qualitative geographical field research. This article seeks to use failure proactively and provocatively as a powerful resource to improve research practice and outcomes, reconsidering and giving voice to it as everyday, productive, and necessary to our continual development as researchers and academics. This article argues that there is much value to be found in failure if it is critically examined and shared, and—crucially—if there is a supportive space in which to exchange our experiences of failing in the field
Early satiety and postprandial fullness in gastroparesis correlate with gastroparesis severity, gastric emptying, and water load testing
BackgroundEarly satiety (ES) and postprandial fullness (PPF) are often present in gastroparesis, but the importance of these symptoms in gastroparesis has not been well‐described. The aims were: (i) Characterize ES and PPF in patients with gastroparesis. (ii) Assess relationships of ES and PPF with etiology of gastroparesis, quality of life, body weight, gastric emptying, and water load testing.MethodsGastroparetic patients filled out questionnaires assessing symptoms (PAGI‐SYM) and quality of life (PAGI‐QOL, SF‐36v2). Patients underwent gastric emptying scintigraphy and water load testing.Key Results198 patients with gastroparesis (134 IG, 64 DG) were evaluated. Early satiety was severe or very severe in 50% of patients. Postprandial fullness was severe or very severe in 60% of patients. Severity scores for ES and PPF were similar between idiopathic and diabetic gastroparesis. Increasing severity of ES and PPF were associated with other gastroparesis symptoms including nausea/vomiting, satiety/early fullness, bloating, and upper abdominal pain and GERD subscores. Increasing severity of ES and PPF were associated with increasing gastroparesis severity, decreased BMI, decreased quality of life from PAGI‐QOL and SF‐36 physical health. Increasing severity of ES and PPF were associated with increasing gastric retention of a solid meal and decreased volume during water load test.Conclusions & InferencesEarly satiety and PPF are commonly severe symptoms in both diabetic and idiopathic gastroparesis. Early satiety and PPF severity are associated with other gastroparesis symptom severities, body weight, quality of life, gastric emptying, and water load testing. Thus, ES and PPF are important symptoms characterizing gastroparesis. ClinicalTrials.gov number: NCT NCT01696747.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136370/1/nmo12981_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136370/2/nmo12981.pd
Gifted and talented education: The English policy highway at a crossroads?
Copyright © 2013 by Sage Publications. This is the author's accepted manuscript. The final published article is available from the link below.In 1999, the British government launched an education program for gifted and talented pupils as part of its Excellence in Cities initiative (EiC) that was initially designed to raise the educational achievement of very able pupils in state-maintained secondary schools in inner-city areas. Although some activities targeting gifted children had already been initiated by various voluntary organizations over several previous decades, this was the first time that the topic of improved provision for these pupils had been placed firmly within the national agenda. This article provides the background to the English gifted and talented policy “highway” and an overview of what was expected of schools. How practitioners responded to the policy, their beliefs and attitudes toward identifying gifted and talented pupils, and the opportunities and challenges that arose along the way to the current crossroads are explored. The need to empower teachers to feel more confident in classroom provisions for gifted and talented pupils is identified along with the potentially pivotal role of action research and “pupil voice” in the process of continued professional development and support
Baseline features and differences in 48 week clinical outcomes in patients with gastroparesis and type 1 vs type 2 diabetes
BackgroundIn studies of diabetic gastroparesis, patients with type 1 and type 2 diabetes mellitus (T1DM, T2DM) are often combined for analyses. We compared gastroparesis severity, healthcare utilization, psychological function, and quality of life in T1DM vs T2DM gastroparesis patients.MethodsQuestionnaire, laboratory, and scintigraphy data from patients with gastroparesis and T1DM and T2DM from seven centers of the National Institute of Diabetes and Digestive and Kidney Diseases Gastroparesis Clinical Research Consortium Registry were compared at enrollment and after 48 weeks. Multiple regression models assessed baseline and followâ up differences between diabetes subtypes.Key ResultsAt baseline, T1DM patients (N = 78) had slower gastric emptying, more hospitalizations, more gastric stimulator implantations, higher hemoglobin A1c (HbA1c), and more anxiety vs T2DM patients (N = 59). Independent discriminators of patients with T1DM vs T2DM included worse gastroesophageal reflux disease, less bloating, more peripheral neuropathy, and fewer comorbidities (p â ¤ 0.05). On followâ up, gastrointestinal (GI) symptom scores decreased only in T2DM (p < 0.05), but not in T1DM patients who reported greater prokinetic, proton pump inhibitor, anxiolytic, and gastric stimulator usage over 48 weeks (p â ¤ 0.03). Gastrointestinal symptoms at baseline and 48 weeks with both subtypes were not associated with HbA1c, peripheral neuropathy, psychological factors, or quality of life.Conclusions & InferencesBaseline symptoms were similar in T1DM and T2DM patients, even though T1DM patients had worse gastric emptying delays and higher HbA1c suggesting other factors mediate symptom severity. Symptom scores at 48 weeks decreased in T2DM, but not T1DM patients, despite increased medical and surgical treatment utilization by T1DM patients. Defining causes of different outcomes in diabetic gastroparesis warrants further investigation.This study defined similarities and differences in gastroparesis severity, healthcare utilization, psychological function, and quality of life in patients with type 1 (T1DM) and type 2 (T2DM) diabetes mellitus and gastroparesis. At baseline enrollment, T1DM patients had higher hemoglobin A1c levels and more severe emptying delays, but the severity of GI symptoms was similar to those of patients with T2DM and gastroparesis. After 48 weeks of followâ up, gastroparesis symptom scores significantly decreased in T2DM patients but not in T1DM patients despite increased use of prokinetic, acid suppressant, anxiolytic, and gastric electrical stimulation therapy in the T1DM group.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/122408/1/nmo12800.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/122408/2/nmo12800_am.pd
Nausea and vomiting in gastroparesis: similarities and differences in idiopathic and diabetic gastroparesis
BackgroundNausea and vomiting are classic symptoms of gastroparesis. It remains unclear if characteristics of nausea and vomiting are similar in different etiologies of gastroparesis. The aims of this article were as follows: to describe characteristics of nausea and vomiting in patients with gastroparesis and to determine if there are differences in nausea and vomiting in diabetic (DG) and idiopathic gastroparesis (IG).MethodsGastroparetic patients enrolling in the NIDDK Gastroparesis Registry underwent assessment with history and questionnaires assessing symptoms, quality of life, and a questionnaire characterizing nausea and vomiting.Key ResultsOf 159 gastroparesis patients (107 IG, 52 DG), 96% experienced nausea, whereas 65% experienced vomiting. Nausea was predominant symptom in 28% and vomiting was predominant in 4%. Nausea was severe or very severe in 41%. PAGI‐SYM nausea/vomiting subscore was greater with increased vomiting severity, but not nausea severity in DG than IG. Nausea was related to meals in 71%; lasting most of the day in 41%. Increasing nausea severity was related to decreased quality of life. Nausea often preceded vomiting in 82% of patients and vomiting often relieved nausea in 30%. Vomiting was more common in DG (81%) compared to IG (57%; p = 0.004). Diabetic patients more often had vomiting in the morning before eating, during the night, and when not eating.Conclusions & InferencesNausea is present in essentially all patients with gastroparesis irrespective of cause and associated with decreased quality of life. In contrast, vomiting was more prevalent, more severe, and occurred more often in DG than IG. Thus, characteristics of vomiting differ in IG vs DG.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134969/1/nmo12893.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134969/2/nmo12893_am.pd
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