5,029 research outputs found
On-line digital computer control of the NERVA nuclear rocket engine
The problem of on-line digital computer control of the NERVA nuclear rocket engine is considered. Proposed is a method of State Dependent State Variable Feedback (SDSVF) as a practical approach to the control of NERVA and other complex nonlinear and/or time-varying systems. The difficulties inherent in other design methods are avoided by defining the optimal closed loop system in terms of a desired transfer function, rather than a performance index to maximize or minimize
Dancing in the Liminal Tension: A Phenomenological Study of how Queer Black Boys Manifest Happiness in an Urban Midwest High School
Urban public schools, as social institutions, have historically played an integral role in reproducing the oppressive ideologies of society writ large. As we depart an era of cautious optimism, many LGBTQ students are teetering on the brink of hopelessness and despair. So often many of these studentsâ voicesâparticularly those of queer Black boysâare still silenced. Ergo, there is a sense of urgency on the part of educators, researchers, and policy-makers to understand how and why queer Black boys consistently disrupt the hegemonic terrain of schools by transforming them into liminal spaces; it is in these sacred spaces-in-between that new identity narratives are constructed, value is created, and authentic happiness is manifested. The purpose of this research in Curriculum Studies is to explore how the narratives of queer Black boys can be used as powerful forms of cultural, political, and social protest that help foster their personal growth toward the pursuit of authentic happiness. This study draws its epistemological lens from queer phenomenology and employs phenomenological interviewing as the method for gathering data from four queer Black high school boys and one transgender female from a small, predominantly African-American city in the Midwest. Drawing upon queer-of-color critique, Daisaku Ikedaâs concept of human revolution, and Tsunesaburo Makiguchiâs framework for value creation and happiness, the researcher captures how queer Black boys attain inner liberation and pursue happiness, despite seemingly insurmountable odds. Although schooling is the primary institution investigated in this study, the researcher takes on a comprehensive approach to understanding the lifeworld of queer Black boys by also exploring homonegativity within other social institutions such as the Black family, the Black church, and the mediaâall of which, the researcher argues, stems from a tradition of White supremacist patriarchy. Schwab reminds us that the student, the teacher, the subject, and the milieu are all co-equal forces in the ongoing development of educational programs. The educational setting is especially important in this phenomenological study of happiness with respect to queer Black boys in an urban high school because it brings into concert all of the other commonplaces in their lives. The participants in this study use their narratives to illustrate how they forge liminal spaces through which to connect, educate, create value, and inspire others to create value amidst adversity, regardless of who one chooses to love, how one chooses to identify, or how un/willing one is to adhere to the status-quo politics of gender and sexual conformity. Drawing on Ikedaâs perspective of human revolution from the âlesserâ to the âgreaterâ self, the researcher posits that a human revolution in queer Black boys promotes a sense of transcendence from their lesser âselfâ, which starts with reclaiming ownership of their truths and their queer bodies. This study ultimately examines the imperative of value creation in the lives of queer Black boys because it helps bring forth their full human potential, while emancipating them from identities that infringe upon it. Their stories help to re-theorize our understanding of âorientationâ in âsexual orientationâ by deconstructing how queer Black boys reside in, and understand, the spatial and temporal aspects of sexual desires
Alien Registration- Kendrick, Samuel D. (Hermon, Penobscot County)
https://digitalmaine.com/alien_docs/8187/thumbnail.jp
Estimating the number of injecting drug users in scotland's HCV-diagnosed population using capture-recapture methods
Educational weight loss interventions in obese and overweight adults with type 2 diabetes : a systematic review and metaâanalysis of randomized controlled trials
Aim
The worldwide prevalence of type 2 diabetes mellitus is increasing, with most individuals with the disease being overweight or obese. Weight loss can reduce diseaseârelated morbidity and mortality and weight losses of 10â15 kg have been shown to reverse type 2 diabetes. This review aimed to determine the effectiveness of communityâbased educational interventions for weight loss in type 2 diabetes.
Methods
This is a systematic review and metaâanalysis of randomized controlled trials (RCT) in obese or overweight adults, aged 18â75 years, with a diagnosis of type 2 diabetes. Primary outcomes were weight and/or BMI. CINAHL, MEDLINE, Embase, Scopus and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched from inception to June 2019. Trials were classified into specified a priori comparisons according to intervention type. A pooled standardized mean difference (SMD) (from baseline to followâup) and 95% confidence intervals (95% CI) between trial groups (differenceâinâdifference) were estimated through randomâeffects metaâanalyses using the inverse variance method. Heterogeneity was quantified using I2 and publication bias was explored visually using funnel plots.
Results
Some 7383 records were screened; 228 fullâtext articles were assessed and 49 RCTs (n = 12 461 participants) were included in this review, with 44 being suitable for inclusion into the metaâanalysis. Pooled estimates of education combined with lowâcalorie, lowâcarbohydrate meal replacements (SMD = â2.48, 95% CI â3.59, â1.49, I2 = 98%) or diets (SMD = â1.25, 95% CI â2.11, â0.39, I2 = 95%) or lowâfat meal replacements (SMD = â1.15, 95%CI â2.05, â1.09, I2 = 85%) appeared most effective.
Conclusion
Lowâcalorie, lowâcarbohydrate meal replacements or diets combined with education appear the most promising interventions to achieve the largest weight and BMI reductions in people with type 2 diabetes
A comparison of underwater visual distance estimates made by scuba divers and a stereo-video system: Implications for underwater visual census of reef fish abundance
Underwater visual census of reef fish by scuba divers is a widely used and useful technique for assessing the composition and abundance of reef fish assemblages, but suffers from several biases and errors. We compare the accuracy of underwater visual estimates of distance made by novice and experienced scientific divers and an underwater stereo-video system. We demonstrate the potential implications that distance errors may have on underwater visual census assessments of reef fish abundance. We also investigate how the accuracy and precision of scuba diver length estimates of fish is affected as distance increases. Distance was underestimated by both experienced ( mean relative error = -11.7%, s.d. = 21.4%) and novice scientific divers (mean relative error = -5.0%, s. d. =17.9%). For experienced scientific divers this error may potentially result in an 82% underestimate or 194% overestimate of the actual area censused, which will affect estimates of fish density. The stereo-video system also underestimated distance but to a much lesser degree (mean relative error = -0.9%, s.d. = 2.6%) and with less variability than the divers. There was no correlation between the relative error of length estimates and the distance of the fish away from the observer
Evaluating the accuracy of diffusion MRI models in white matter
Models of diffusion MRI within a voxel are useful for making inferences about
the properties of the tissue and inferring fiber orientation distribution used
by tractography algorithms. A useful model must fit the data accurately.
However, evaluations of model-accuracy of some of the models that are commonly
used in analyzing human white matter have not been published before. Here, we
evaluate model-accuracy of the two main classes of diffusion MRI models. The
diffusion tensor model (DTM) summarizes diffusion as a 3-dimensional Gaussian
distribution. Sparse fascicle models (SFM) summarize the signal as a linear sum
of signals originating from a collection of fascicles oriented in different
directions. We use cross-validation to assess model-accuracy at different
gradient amplitudes (b-values) throughout the white matter. Specifically, we
fit each model to all the white matter voxels in one data set and then use the
model to predict a second, independent data set. This is the first evaluation
of model-accuracy of these models. In most of the white matter the DTM predicts
the data more accurately than test-retest reliability; SFM model-accuracy is
higher than test-retest reliability and also higher than the DTM, particularly
for measurements with (a) a b-value above 1000 in locations containing fiber
crossings, and (b) in the regions of the brain surrounding the optic
radiations. The SFM also has better parameter-validity: it more accurately
estimates the fiber orientation distribution function (fODF) in each voxel,
which is useful for fiber tracking
Effect of the Negative Ion Band on Athletic Performance
Negative Ion bands have been suggested to increase various areas of athletic performance. At this time, the authors are not aware of any studies on these bands. Purpose: To determine if a True Power Energy Band (True Power LLC, Melrose, MA) had an effect on various measures of performance. Methods: Forty-one subjects (age = 29.3±7.1 yrs, ht = 171.5±9.7 cm, wt = 85.4±23.2 kg) had their height and weight measured and were then randomized to wear the True Power band (TB) or a silver bracelet placebo band (PB) (Hobby Lobby). After 5 days, subjects were assessed on reaction time using a color response test and a response test in which the subject clicked a highlighted dot as it appeared in a 5x5 table (www.intelligencetest.com/reflex/index). The subjects then performed a standard balance test (stork test) without shoes, two flexibility tests (V-sit-and-reach & trunk rotation), and two strength tests (hand grip using a dynamometer & push-ups to exhaustion). The tests were conducted in this order with as much rest between trials as needed. One week later, this same procedure was followed but with the opposing band. Repeated measures ANOVA was used to determine if differences exist between the bands, with Alpha set at .05. Results: There were no significant differences in the tests of color (TB = 0.43±0.14, PB = 0.41±0.11 sec), dots (TB = 16.9±3.0, PB = 17.0±2.6 score), stork (TB = 4.4±3.4, PB = 4.7±4.1 sec), V-sit-and-reach (TB = 15.2±16.8, PB = 15.5±17.3 cm), trunk rotation (TB = 35.8±15.0, PB = 37.3±14.0 cm), hand grip (TB = 42.4±12.1, PB = 42.8±11.0 kg), and push-ups (TB = 23.4±10.5, PB = 25.8±11.7 total), p \u3e .05 for all tests. Conclusion: There seems to be no effect of Negative Ion bands on tests of reaction time, balance, flexibility, or muscular strength. The claims of performance in these types of bands have yet to be validated
- âŠ