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1.
Proc Natl Acad Sci U S A ; 114(12): 3085-3090, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28265087

RESUMO

Active-learning pedagogies have been repeatedly demonstrated to produce superior learning gains with large effect sizes compared with lecture-based pedagogies. Shifting large numbers of college science, technology, engineering, and mathematics (STEM) faculty to include any active learning in their teaching may retain and more effectively educate far more students than having a few faculty completely transform their teaching, but the extent to which STEM faculty are changing their teaching methods is unclear. Here, we describe the development and application of the machine-learning-derived algorithm Decibel Analysis for Research in Teaching (DART), which can analyze thousands of hours of STEM course audio recordings quickly, with minimal costs, and without need for human observers. DART analyzes the volume and variance of classroom recordings to predict the quantity of time spent on single voice (e.g., lecture), multiple voice (e.g., pair discussion), and no voice (e.g., clicker question thinking) activities. Applying DART to 1,486 recordings of class sessions from 67 courses, a total of 1,720 h of audio, revealed varied patterns of lecture (single voice) and nonlecture activity (multiple and no voice) use. We also found that there was significantly more use of multiple and no voice strategies in courses for STEM majors compared with courses for non-STEM majors, indicating that DART can be used to compare teaching strategies in different types of courses. Therefore, DART has the potential to systematically inventory the presence of active learning with ∼90% accuracy across thousands of courses in diverse settings with minimal effort.


Assuntos
Aprendizagem Baseada em Problemas/normas , Ciência/educação , Ensino/normas , Humanos , Som , Estudantes , Tecnologia , Universidades/normas
2.
J Org Chem ; 75(21): 7129-40, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-20925362

RESUMO

The unusual base-induced ring-enlargement of halomethylenecyclobutanes to 1-halocyclopentenes was examined with unsymmetrical and (13)C-labeled substrates to study regio- and stereochemical characteristics. Migration of a ring carbon atom (single migration) or simultaneous migration of a ring carbon atom and the halide (double migration) gives the ring-enlarged products. (13)C-labeling experiments established that both rearrangements occur with retention of configuration at the migrating center. These systems are suggested as models for the Fritsch-Buttenberg-Wiechell (FBW) rearrangement.

3.
Ann Am Thorac Soc ; 15(12): 1369-1381, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30499721

RESUMO

More than 1.5 million adults in the United States use supplemental oxygen for a variety of respiratory disorders to improve their quality of life and prolong survival. This document describes recommendations from a multidisciplinary workshop convened at the ATS International Conference in 2017 with the goal of optimizing home oxygen therapy for adults. Ideal supplemental oxygen therapy is patient-specific, provided by a qualified clinician, includes an individualized prescription and therapeutic education program, and offers oxygen systems that are safe, promote mobility, and treat hypoxemia. Recently, patients and clinicians report a growing number of problems with home oxygen in the United States. Oxygen users experience significant functional, mechanical, and financial problems and a lack of education related to their oxygen equipment-problems that impact their quality of life. Health care providers report a lack of readily accessible resources needed to prescribe oxygen systems correctly and efficiently. Patients with certain lung diseases are affected more than others because of physically unmanageable or inadequate portable systems. Analysis is needed to quantify the unintended impact that the Centers for Medicare and Medicaid Services Competitive Bidding Program has had on patients receiving supplemental oxygen from durable medical equipment providers. Studies using effectiveness and implementation research designs are needed to develop and evaluate new models for patient education, identify effective ways for stakeholders to interface, determine the economic benefit of having respiratory therapists perform in-home education and follow-up testing, and collaborate with technology companies to improve portable oxygen devices. Generation of additional evidence of the benefit of supplemental oxygen across the spectrum of advanced lung diseases and the development of clinical practice guidelines should both be prioritized.


Assuntos
Atenção à Saúde/organização & administração , Política de Saúde , Serviços de Assistência Domiciliar , Oxigenoterapia , Educação , Humanos , Defesa do Paciente , Estados Unidos
4.
J Org Chem ; 62(23): 8188-8192, 1997 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-11671930

RESUMO

Two novel, highly potent, cytotoxic macrolides, salicylihalamides A (1) and B (2), were isolated from the sponge Haliclona sp. This new macrolide class incorporates salicylic acid, a 12-membered lactone ring, and an enamide side chain. COMPARE pattern-recognition analyses of the NCI 60-cell mean graph screening profiles of 1 did not reveal any significant correlations to the profiles of known antitumor compounds in the NCI's "standard agent database", thus supporting the conclusion that the salicylihalamides represent a potentially important new class for antitumor lead optimization and in vivo investigations.

5.
J Nat Prod ; 71(5): 898-901, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18407694

RESUMO

The synthesis of a simple analogue of salicylihalamide A with a truncated lactone ring (+/- 2) was achieved in 10 steps. Its cytotoxicity profile in the NCI 60-cell-line human tumor assay differed significantly from that of salicylihalamide A in both level and specificity.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Animais , Antineoplásicos/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Poríferos/química , Estereoisomerismo
6.
J Nat Prod ; 71(3): 453-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18197605

RESUMO

A new proline-rich cyclodecapeptide, designated stylopeptide 2, has been isolated from a cytotoxic extract of the Papua New Guinea marine sponge Stylotella sp. and found to correspond to structure 1. The structural assignment was based on HRMS collision-induced dissociation tandem mass spectrometry (CID MS/MS), NMR spectroscopic data, and amino acid analysis, which led to assignment of the absolute configuration.


Assuntos
Peptídeos Cíclicos/química , Peptídeos Cíclicos/isolamento & purificação , Poríferos/química , Animais , Estrutura Molecular , Papua Nova Guiné , Prolina/química
7.
J Nat Prod ; 65(9): 1303-6, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12350152

RESUMO

Clavosolides A-D (1-4), dimeric macrolides incorporating cyclopropyl, tetrahydropyranyl, and glycosidic ring systems, were isolated from the cytotoxic extract of a Philippines collection of the marine sponge Myriastra clavosa. The structures of the clavosolides, which occurred as only trace metabolites, were elucidated through extensive NMR spectroscopic analyses. Clavosolides A (1) and B (2) were recently reported metabolites from M. clavosa, while the unsymmetrical dimers clavosolides C (3) and D (4) had new structures.


Assuntos
Antineoplásicos/isolamento & purificação , Macrolídeos/isolamento & purificação , Poríferos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama , Carcinoma Pulmonar de Células não Pequenas , Neoplasias do Sistema Nervoso Central , Cromatografia Líquida de Alta Pressão , Neoplasias do Colo , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Neoplasias Pulmonares , Macrolídeos/química , Macrolídeos/farmacologia , Melanoma , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Neoplasias Ovarianas , Filipinas , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo , Células Tumorais Cultivadas/efeitos dos fármacos
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