Creating a Differentiated Mathematics Classroom

Recognizing different mathematical learning styles and adapting differentiated teaching strategies can facilitate student learning

Ray Casting Architectures for Volume Visualization

Real-time visualization of large volume datasets demands high performance computation, pushing the storage, processing, and data communication requirements to the limits of current technology. General purpose parallel processors have been used to visualize moderate size datasets at interactive frame rates; however, the cost and size of these supercomputers inhibits the widespread use for real-time visualization. This paper surveys several special purpose architectures that seek to render volumes at interactive rates. These specialized visualization accelerators have cost, performance, and size advantages over parallel processors. All architectures implement ray casting using parallel and pipelined hardware. We introduce a new metric that normalizes performance to compare these architectures. The architectures included in this survey are VOGUE, VIRIM, Array Based Ray Casting, EM-Cube, and VIZARD II. We also discuss future applications of special purpose accelerators.Engineering and Applied Science

Varicoid carcinoma of the esophagus

Two cases of esophageal squamous cell carcinoma closely resembling esophageal varices on radiographic examination have been presented. Rigidity and absence of peristalsis at fluoroscopy, as well as no change in appearance of the polypoidal filling defects with spot filming, differentiate varicoid carcinoma from esophageal varices. The lack of involvement of the distal esophagus was helpful in differentiating carcinoma from varices in one of the cases.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44382/1/10620_2005_Article_BF01073353.pd

Uneven development and scale politics in Southern Africa: what we learn from Neil Smith

Southern Africa is probably the most unevenly developed region on earth, combining the most modern technologies and an advanced working class with the world’s extremes of inequality and social militancy. The two most extreme countries, both with settler–colonial populations and accumulation processes that created durable class/race/gender distortions and extreme environmental degradation, are South Africa and Zimbabwe—both of which Neil Smith visited in 1995. His contribution to our understanding of political economy, before and after, was exemplary. We consider in this article how Smith’s theory assisted in the understanding of crisis-ridden financial markets within the framework of capital overaccumulation and intensified spatial unevenness; the politics of scale, difference and community; and the ways that class apartheid and durable racism in the two countries together fit within contemporary geopolitical economy.IS

Environmental Regulation Can Arise Under Minimal Assumptions

Models that demonstrate environmental regulation as a consequence of organism and environment coupling all require a number of core assumptions. Many previous models, such as Daisyworld, require that certain environment-altering traits have a selective advantage when those traits also contribute towards global regulation. We present a model that results in the regulation of a global environmental resource through niche construction without employing this and other common assumptions. There is no predetermined environmental optimum towards which regulation should proceed assumed or coded into the model. Nevertheless, polymorphic stable states that resist perturbation emerge from the simulated co-evolution of organisms and environment. In any single simulation a series of different stable states are realised, punctuated by rapid transitions. Regulation is achieved through two main subpopulations that are adapted to slightly different resource values, which force the environmental resource in opposing directions. This maintains the resource within a comparatively narrow band over a wide range of external perturbations. Population driven oscillations in the resource appear to be instrumental in protecting the regulation against mutations that would otherwise destroy it. Sensitivity analysis shows that the regulation is robust to mutation and to a wide range of parameter settings. Given the minimal assumptions employed, the results could reveal a mechanism capable of environmental regulation through the by-products of organisms

What Insights Do Patients and Caregivers Have on Acute Kidney Injury and Posthospitalization Care? A Single-Centre Qualitative Study from Toronto, Canada

Objectives Hospitalisation with acute kidney injury (AKI) is associated with short-term and long-term adverse events, but patient and caregiver experiences with AKI are not well described. We sought to better understand patient and caregiver perspectives after a hospitalisation with AKI to inform discharge strategies that may improve outcomes for this high-risk population. Design Qualitative study with semistructured interviews. Setting Tertiary care hospital in Toronto, Ontario, Canada. Participants Adult patients (n=15) who survived a hospitalisation with Kidney Disease Improving Global Outcomes stage 2 or 3 AKI from May to December 2016. We also interviewed five patient caregivers. We required patients to have no previous evidence of severe chronic kidney disease (ie, prior receipt of dialysis, previous kidney transplantation or pre-existing estimated glomerular filtration rate (eGFR) under 30 mL/min/1.73 m2). Results We identified three over-arching themes: (1) prioritisation of conditions other than AKI, reflected by the importance placed on other comorbidities and the omission of AKI as part of the ongoing medical history; (2) variability in comprehension of the significance of AKI, represented by minimal knowledge of the causes and symptoms associated with AKI, along with misinformation on the kidneys’ ability to self-repair; and (3) anxiety from discharge planning and competing health demands, illustrated by complicated discharge plans involving multiple specialist appointments. Conclusions Patients and caregivers view AKI as a short-term and reversible condition, giving it little thought during the postdischarge period. As a result, reliance on patients and caregivers to report an episode of AKI to their outpatient physicians is unlikely to be successful. Patient-centred tools and decision aids are needed to bridge the gap between a hospitalisation with AKI and the safe transition to the outpatient setting

Inventory control with seasonality of lead times

The practical challenges posed by the seasonality of lead times have largely been ignored within the inventory control literature. The length of the seasons, as well as the length of the lead times during a season, may demonstrate cyclical patterns over time. This study examines whether inventory control policies that anticipate seasonal lead-time patterns can reduce costs. We design a framework for characterizing different seasonal lead-time inventory problems. Subsequently, we examine the effect of deterministic and stochastic seasonal lead times within periodic review inventory control systems. We conduct a base case analysis of a deterministic system, enabling two established and alternating lead-time lengths that remain valid through known intervals. We identify essential building blocks for developing solutions to seasonal lead-time problems. Lastly, we perform numerical experiments to evaluate the cost benefits of implementing an inventory control policy that incorporates seasonal lead-time lengths. The findings of the study indicate the potential for cost improvements. By incorporating seasonality in length of seasons and length of lead times within the season into the control models, inventory controllers can make more informed decisions when ordering their raw materials. They need smaller buffers against lead-time variations due to the cyclical nature of seasonality. Reductions in costs in our experiments range on average between 18.9 and 26.4% (depending on safety time and the probability of the occurrence of stock out). Therefore, inventory control methods that incorporate seasonality instead of applying large safety stock or safety time buffers can lead to substantial cost reductions

Rethinking the concept of labour

Is labour a useful concept for anthropology today? This essay attempts to respond theoretically to the challenge that the contributions to this special issue empirically pose. The essay rethinks the concept of labour by addressing three questions that deal with the relation of human work effort and capital accumulation: the first refers to alienation; the second to the difference between abstract and concrete labour; and the third to ambiguity. Over the years, these issues have addressed particular aspects of social reproduction, helping define labour as a concept, albeit a heterogeneous one, that is relationally linked to capital. Dislocation, together with the parallel concepts of dispossession, disorganization, disconnection, and differentiation, emerges prominently in the analyses of contemporary labour transformations and specificities. Finally, the essay engages with seemingly disappearing labour futures and what this means for the concept of labour. What is the value of work for capital and, conversely, the value of labouring for people today

Centerscope

Centerscope, formerly Scope, was published by the Boston University Medical Center "to communicate the concern of the Medical Center for the development and maintenance of improved health care in contemporary society.

Antidepressant Controlled Trial For Negative Symptoms In Schizophrenia (ACTIONS): a double-blind, placebo-controlled, randomised clinical trial

Background Negative symptoms of schizophrenia represent deficiencies in emotional responsiveness, motivation, socialisation, speech and movement. When persistent, they are held to account for much of the poor functional outcomes associated with schizophrenia. There are currently no approved pharmacological treatments. While the available evidence suggests that a combination of antipsychotic and antidepressant medication may be effective in treating negative symptoms, it is too limited to allow any firm conclusions. Objective To establish the clinical effectiveness and cost-effectiveness of augmentation of antipsychotic medication with the antidepressant citalopram for the management of negative symptoms in schizophrenia. Design A multicentre, double-blind, individually randomised, placebo-controlled trial with 12-month follow-up Setting Adult psychiatric services, treating people with schizophrenia. Participants Inpatients or outpatients with schizophrenia, on continuing, stable antipsychotic medication, with persistent negative symptoms at a criterion level of severity. Interventions Eligible participants were randomised 1 : 1 to treatment with either placebo (one capsule) or 20 mg of citalopram per day for 48 weeks, with the clinical option at 4 weeks to increase the daily dosage to 40 mg of citalopram or two placebo capsules for the remainder of the study. Main Outcome Measures The primary outcomes were quality of life measured at 12 and 48 weeks assessed using the Heinrich’s Quality of Life Scale, and negative symptoms at 12 weeks measured on the negative symptom subscale of the Positive and Negative Syndrome Scale. Results No therapeutic benefit in terms of improvement in quality of life or negative symptoms was detected for citalopram over 12 weeks or at 48 weeks, but secondary analysis suggested modest improvement in the negative symptom domain, avolition/amotivation, at 12 weeks (mean difference –1.3, 95% confidence interval–2.5 to–0.09). There were no statistically significant differences between the two treatment arms over 48-week follow-up in either the health economics outcomes or costs, and no differences in the frequency or severity of adverse effects, including corrected QT interval prolongation. Limitations The trial under-recruited, partly because cardiac safety concerns about citalopram were raised, with the 62 participants recruited falling well short of the target recruitment of 358. Although this was the largest sample randomised to citalopram in a randomised controlled trial of antidepressant augmentation for negative symptoms of schizophrenia and had the longest follow-up, the power of statistical analysis to detect significant differences between the active and placebo groups was limited. Conclusion Although adjunctive citalopram did not improve negative symptoms overall, there was evidence of some positive effect on avolition/amotivation, recognised as a critical barrier to psychosocial rehabilitation and achieving better social and community functional outcomes. Comprehensive assessment of side-effect burden did not identify any serious safety or tolerability issues. The addition of citalopram as a long-term prescribing strategy for the treatment of negative symptoms may merit further investigation in larger studies. Future Work Further studies of the viability of adjunctive antidepressant treatment for negative symptoms in schizophrenia should include appropriate safety monitoring and use rating scales that allow for evaluation of avolition/amotivation as a discrete negative symptom domain. Overcoming the barriers to recruiting an adequate sample size will remain a challenge.</p