Digestive enzyme activities in the guts of bonnethead sharks (Sphyrna tiburo) provide insight into their digestive strategy and evidence for microbial digestion in their hindguts

Few investigations have studied digestive enzyme activities in the alimentary tracts of sharks to gain insight into how these organisms digest their meals. In this study, we examined the activity levels of proteases, carbohydrases, and lipase in the pancreas, and along the anterior intestine, spiral intestine, and colon of the bonnethead shark, Sphyrna tiburo. We then interpreted our data in the context of a rate-yield continuum to discern this shark's digestive strategy. Our data show anticipated decreasing patterns in the activities of pancreatic enzymes moving posteriorly along the gut, but also show mid spiral intestine peaks in aminopeptidase and lipase activities, which support the spiral intestine as the main site of absorption in bonnetheads. Interestingly, we observed spikes in the activity levels of N-acetyl-β-d-glucosaminidase and β-glucosidase in the bonnethead colon, and these chitin- and cellulose-degrading enzymes, respectively, are likely of microbial origin in this distal gut region. Taken in the context of intake and relatively long transit times of food through the gut, the colonic spikes in N-acetyl-β-d-glucosaminidase and β-glucosidase activities suggest that bonnetheads take a yield-maximizing strategy to the digestive process, with some reliance on microbial digestion in their hindguts. This is one of the first studies to examine digestive enzyme activities along the gut of any shark, and importantly, the data match with previous observations that sharks take an extended time to digest their meals (consistent with a yield-maximizing digestive strategy) and that the spiral intestine is the primary site of absorption in sharks.PostprintPeer reviewe

Disease-modifying therapy adherence and associated factors in a national sample of Medicare patients with multiple sclerosis

OBJECTIVES: Disease-modifying therapies (DMTs) reduce relapse rates and disability progression for relapsing multiple sclerosis (MS). Although 25% to 30% of all US patients with MS are Medicare beneficiaries, limited information exists on this population. This is the first study using national Medicare data to (1) describe characteristics of patients with MS using DMTs, (2) estimate adherence to DMTs over a 1-year and 3-year follow-up, and (3) examine factors associated with DMT adherence. METHODS: This retrospective claims analysis used 2011-2014 100% Medicare files. Monthly adherence to MS DMTs was defined as the proportion of days covered ≥0.80 with any DMT in each month for 1-year (n = 36 593) and 3-year (n = 17 599) follow-up samples of MS DMT users. Generalized estimating equation logistic regressions were used to estimate factors associated with adherence to DMTs. RESULTS: Over 90% of patients were eligible for Medicare owing to disability, and about three-quarters qualified for low-income subsidies. A downward trend in DMT adherence was observed over time in both samples. Monthly adherence dropped significantly between December of the prior year to January of the following year (from 76% to 65% in the 1-year follow-up sample and similar drops seen across all years in the 3-year follow-up sample). Multivariable regressions indicated characteristics such as being low-income, having a disability, and having high patient out-of-pocket DMT costs associated with poor adherence to DMTs. CONCLUSION: Our study provides important insights into the characteristics and DMT adherence of Medicare patients with MS and highlights the need for interventions and policies mitigating barriers to adherence in this population

Attitude determination of a high altitude balloon system. Part 1: Development of the mathematical model

A mathematical model for predicting the three dimensional motion of the balloon system is developed, which includes the effects of bounce, pendulation and spin of each subsystem. Boundary layer effects are also examined, along with the aerodynamic forces acting on the balloon. Various simplified forms of the system mathematical model were developed, based on an order of magnitude analysis

Why Jenny Can’t Figure Out Which Of These Messages Is A Covert Information Operation

We view foreign interference in US and UK elections via social manipulation through the lens of usable security. Our goal is to provide advice on what interventions on the socio-technical election system are likely to work, and which are likely to fail. Strategies that the usable security literature indicates are likely to work are those that (1) avoid overloading the user's primary task; (2) help people understand negative consequences of their actions; and (3) support the long-term education of users with analytic reasoning skills and adequate background knowledge. Several of the responses to election interference proposed by governments and technology companies so far do not abide by these recommendations and are likely to be ineffective

A new model for diabetes-focused capacity building – lessons from Sri Lanka

Abstract Sri Lanka is experiencing a rapid increase in the number of people with diabetes mellitus (DM) due to population growth and aging. Physician shortages, outdated technology, and insufficient health education have contributed to the difficulties associated with managing the burden of disease. New models of chronic disease management are needed to address the increasing prevalence of DM. Medical students, business students, and faculty members from the University of Michigan partnered with the Grace Girls’ Home, Trincomalee General Hospital, and Selvanayakapuram Central Hospital to identify and train diabetes-focused medical assistants (MAs) to collect and enter patient data and educate patients about their disease. Return visits to these MAs were encouraged so that patient progress and disease progression could be tracked longitudinally. Data entry was conducted through a cloud-based mechanism, facilitating patient management and descriptive characterization of the population. We implemented this pilot program in June 2016 in coordination with Trincomalee General Hospital and Selvanayakapuram Central Hospital. Over a 12-month period, 93 patients were systematically assessed by the medical assistants. All patients received education and were provided materials after the visit to better inform them about the importance of controlling their disease. Fifteen percent (14/93) of patients returned for follow-up consultation. Trained MAs have the potential to provide support to physicians working in congested health systems in low-resource settings. Public investment in training programs for MAs and greater acceptance by physicians and patients will be essential for handling the growing burden associated with chronic illnesses like DM. Trained MAs may also play a role in improved patient education and awareness regarding diabetes self-management.https://deepblue.lib.umich.edu/bitstream/2027.42/146742/1/40842_2018_Article_74.pd