Influence of blood glucose on heart rate and cardiac autonomic function. The DESIR study.

International audienceOBJECTIVES:   To evaluate in a general population, the relationships between dysglycaemia, insulin resistance and metabolic variables, and heart rate, heart rate recovery and heart rate variability. METHODS:   Four hundred and forty-seven participants in the Data from an Epidemiological Study on the Insulin Resistance syndrome (DESIR) study were classified according to glycaemic status over the preceding 9 years. All were free of self-reported cardiac antecedents and were not taking drugs which alter heart rate. During five consecutive periods: rest, deep breathing, recovery, rest and lying to standing, heart rate and heart rate varability were evaluated and compared by ANCOVA and trend tests across glycaemic classes. Spearman correlation coefficients quantified the relations between cardio-metabolic risk factors, heart rate and heart rate varability. RESULTS:   Heart rate differed between glycaemic groups, except during deep breathing. Between rest and deep-breathing periods, patients with diabetes had a lower increase in heart rate than others (P(trend) < 0.01); between deep breathing and recovery, the heart rate of patients with diabetes continued to increase, for others, heart rate decreased (P(trend) < 0.009). Heart rate was correlated with capillary glucose and triglycerides during the five test periods. Heart rate variability differed according to glycaemic status, especially during the recovery period. After age, sex and BMI adjustment, heart rate variability was correlated with triglycerides at two test periods. Change in heart rate between recovery and deep breathing was negatively correlated with heart rate variability at rest, (r=-0.113, P < 0.05): lower resting heart rate variability was associated with heart rate acceleration. CONCLUSIONS:   Heart rate, but not heart rate variability, was associated with glycaemic status and capillary glucose. After deep breathing, heart rate recovery was altered in patients with known diabetes and was associated with reduced heart rate variability. Being overweight was a major correlate of heart rate variability

Reconfiguration, contestation, and decline: conceptualizing mature large technical systems

Large technical systems (LTS) are integral to modern lifestyles but arduous to analyze. In this paper, we advance a conceptualization of LTS using the notion of mature “phases,” drawing from insights into innovation studies, science and technology studies, political science, the sociology of infra- structure, history of technology, and governance. We begin by defining LTS as a unit of analysis and explaining its conceptual utility and novelty, situating it among other prominent sociotechnical theories. Next, we argue that after LTS have moved through the (overlapping) phases proposed by Thomas Hughes of invention, expansion, growth, momentum, and style,mature LTS undergo the additional (overlapping) phases of reconfiguration, contestation (subject to pressures such as drift and crisis), and eventually stagnation and decline. We illustrate these analytical phases with historical case studies and the conceptual literature, and close by suggesting future research to refine and develop the LTS framework, particularly related to more refined typologies, temporal dimensions, and a broadening of system users. We aim to contribute to theoretical debates about the coevolution of LTS as well as empirical discussions about system-related use, socio- technical change, and policy-making

Immobilized fibrinogen activates human platelets through GPVI

GPVI, a major platelet activation receptor for collagen and fibrin, is considered as a particularly promising safe antithrombotic target. In this study, we show that human GPVI signals upon platelet adhesion to fibrinogen. Full spreading of human platelets on fibrinogen is abolished in platelets from GPVI-deficient patients suggesting that fibrinogen activates platelets through GPVI. While mouse platelets fail to spread on fibrinogen, human-GPVI-transgenic mouse platelets show full spreading and increased Ca2+ signalling through the tyrosine kinase Syk. Direct binding of fibrinogen to human GPVI was shown by surface plasmon resonance and by increased adhesion of human GPVI-transfected Rbl-2H3 cells to fibrinogen relative to mock-transfected cells. Blockade of human GPVI with the Fab of the monoclonal antibody 9O12 impairs platelet aggregation on preformed platelet aggregates in flowing blood independent of collagen and fibrin exposure. These results demonstrate that human GPVI binds to immobilized fibrinogen and show that this contributes to platelet spreading and platelet aggregation under flow

Development of the Bélanger Equation and Backwater Equation by Jean-Baptiste Bélanger (1828)

A hydraulic jump is the sudden transition from a high-velocity to a low-velocity open channel flow. The application of the momentum principle to the hydraulic jump is commonly called the Bélanger equation, but few know that Bélanger's (1828) treatise was focused on the study of gradually varied open channel flows. Further, although Bélanger understood the rapidly-varied nature of the jump flow, he applied incorrectly the Bernoulli principle in 1828, and corrected his approach 10 years later. In 1828, his true originality lay in the successful development of the backwater equation for steady, one-dimensional gradually-varied flows in an open channel, together with the introduction of the step method, distance calculated from depth, and the concept of critical flow conditions

Drug discovery for Diamond-Blackfan anemia using reprogrammed hematopoietic progenitors

Diamond-Blackfan anemia (DBA) is a congenital disorder characterized by the failure of erythroid progenitor differentiation, severely curtailing red blood cell production. Because many DBA patients fail to respond to corticosteroid therapy, there is considerable need for therapeutics for this disorder. Identifying therapeutics for DBA requires circumventing the paucity of primary patient blood stem and progenitor cells. To this end, we adopted a reprogramming strategy to generate expandable hematopoietic progenitor cells from induced pluripotent stem cells (iPSCs) from DBA patients. Reprogrammed DBA progenitors recapitulate defects in erythroid differentiation, which were rescued by gene complementation. Unbiased chemical screens identified SMER28, a small-molecule inducer of autophagy, which enhanced erythropoiesis in a range of in vitro and in vivo models of DBA. SMER28 acted through autophagy factor ATG5 to stimulate erythropoiesis and up-regulate expression of globin genes. These findings present an unbiased drug screen for hematological disease using iPSCs and identify autophagy as a therapeutic pathway in DBA.National Institute of Diabetes and Digestive and Kidney Diseases (U.S.) (Grant R24-DK092760)National Institute of Diabetes and Digestive and Kidney Diseases (U.S.) (Grant R24-DK49216)National Institute of Diabetes and Digestive and Kidney Diseases (U.S.) (Grant U54DK110805)National Heart, Lung, and Blood Institute (Grant UO1-HL100001)National Heart, Lung, and Blood Institute (Grant U01HL134812)National Heart, Lung, and Blood Institute (Grant R01HL04880)National Institutes of Health (U.S.) (Grant R24OD017870-01

Advances in small lasers

M.T.H was supported by an Australian Research council Future Fellowship research grant for this work. M.C.G. is grateful to the Scottish Funding Council (via SUPA) for financial support.Small lasers have dimensions or modes sizes close to or smaller than the wavelength of emitted light. In recent years there has been significant progress towards reducing the size and improving the characteristics of these devices. This work has been led primarily by the innovative use of new materials and cavity designs. This Review summarizes some of the latest developments, particularly in metallic and plasmonic lasers, improvements in small dielectric lasers, and the emerging area of small bio-compatible or bio-derived lasers. We examine the different approaches employed to reduce size and how they result in significant differences in the final device, particularly between metal- and dielectric-cavity lasers. We also present potential applications for the various forms of small lasers, and indicate where further developments are required.PostprintPeer reviewe

Ursinus College Bulletin, August 1978

Basic requirements: What should they include? • College implements task force recommendations on student life: Ruth Harris named Dean of Students • Developing the individual • Ursinus after dark: It\u27s a real education • Alumni profile: John Ulmer has done it all but prefers directing • Alumni Day • Commencement • Evan Snyder \u2744 named interim Dean • Sports shorts • Calendar revised • The Weekly ceases publication • Memories 1/2 price • New dues and you • Election results • Hot news • Dialing for dollars • Healthy prognosis • Norman Harberger \u2750 to head alumni fund • Terminal grammar • New alumni secretary named • Taking the show on the road • Ursinus subject of essay • William Elliott Pool makes a big splash in Collegeville • News notes • Evening School • Deaths • Births • Marriageshttps://digitalcommons.ursinus.edu/new_bulletin/1022/thumbnail.jp

Achieving enhanced gain in photorefractive polymers by eliminating electron contributions using large bias fields

Photorefractive polymers have been extensively studied for over two decades and have found applications in holographic displays and optical image processing. The complexity of these materials arises from multiple charge contributions, for example, leading to the formation of competing photorefractive gratings. It has been recently shown that in a photorefractive polymer at relatively moderate applied electric fields the primary charge carriers (holes) establish an initial grating, followed by a subsequent competing grating (electrons) resulting in a decreased two-beam coupling and diffraction efficiencies. In this paper, it is shown that with relatively large sustainable bias fields, the two-beam coupling efficiency is enhanced owing to a decreased electron contribution. These results also explain the cause of dielectric breakdown experienced under large bias fields. Our conclusions are supported by self-pumped transient two-beam coupling and photocurrent measurements as a function of applied bias fields at different wavelengths

Bone mineral density in patients with inherited bone marrow failure syndromes

BackgroundPatients with inherited bone marrow failure syndromes (IBMFS) may have several risk factors for low bone mineral density (BMD). We aimed to evaluate the prevalence of low BMD in IBMFS and determine the associated risk factors.MethodsPatients with IBMFS with at least one dual-energy X-ray absorptiometry (DXA) scan were evaluated. Diagnosis of each IBMFS, Fanconi anemia (FA), dyskeratosis congenita, Diamond-Blackfan anemia, and Shwachman-Diamond syndrome was confirmed by syndrome-specific tests. Data were gathered on age, height, and clinical history. DXA scans were completed at the lumbar spine, femoral neck, and forearm. BMD was adjusted for height (HAZ) in children (age ≤20 years). Low BMD was defined as a BMD Z-score and HAZ ≤-2 in adults and children, respectively, in addition to patients currently on bisphosphonate therapy.ResultsNine of thirty-five adults (26%) and eleven of forty children (27%) had low BMD. Adults with FA had significantly lower BMD Z-scores than those with other diagnoses; however, HAZ did not vary significantly in children by diagnosis. Risk factors included hypogonadism, iron overload, and glucocorticoid use.ConclusionsAdults and children with IBMFS have high prevalence of low BMD. Prompt recognition of risk factors and management are essential to optimize bone health