9,909 research outputs found
Victor Heiser and the Rockefeller Foundation as a Medium for the Intercolonial Transfer of Health Management Knowledge in Asia in the Era of the League of Nations
Victor Heiser was in charge of Rockefeller programs in Asia and the Pacific (which his contemporaries called the "Pacific region") as Director for the East of the International Health Board (IHB) of the Rockefeller Foundation from 1915 to 1934. The IHB provided a substantial portion (30-40 percent) of the funding for international health projects of the League of Nations Health Organization (LNHO, 1921-46), and also conducted its own programs in various parts of the world. In recent years, scholars have begun to see the League as an important harbinger of global norms in the following era of the United Nations, and the role of the LNHO is in particularly well acknowledged. Heiser oversaw a large part of the LNHO's international health work in Asia and the Pacific. Compared to other Rockefeller IHB officers who worked in Asia, such as John B. Grant, Roger Greene, and Selskar Gunn, however, Heiser's work as Director for the East, especially in the relations between the IHB and the League, has been relatively unknown. What kind of man was he, and what principles or philosophies for international health did he have? What role did he play in defining the nature of the IHB's involvement in the LNHO work in Asia and the Pacific
Analysis of Endoscopic Electronic Image of Intramucosal Gastric Carcinoma Using a Software Program for Calculating Hemoglobin Index
Hemoglobin is the predominent pigment in the gastrointestinal mucosa, and the development of electronic endoscopy has made it possible to quantitatively measure the mucosal hemoglobin volume, by using a hemoglobin index (IHb). The aims of this study were to make a software program to calculate the IHb and then to investigate whether the mucosal IHb determined from the electronic endoscopic data is a useful marker for evaluating the color of intramucosal gastric carcinoma with regard to its value for discriminating between the histologic types. We made a software program for calculating the IHb in the endoscopic images. By using this program, the mean values of the IHb for the carcinoma (IHb-C) and those of the IHb for the surrounding non-cancerous mucosa (IHb-N) were calculated in 75 intestinal-type and 34 diffuse-type intramucosal gastric carcinomas. We then analyzed the ratio of the IHb-C to the IHb-N (C/N ratio). The C/N ratio in the intestinal-type carcinoma group was higher than that in the diffuse-type carcinoma group (p<0.001). In the diffuse-type carcinoma group, the C/N ratio in the body was lower than that in the antrum (p=0.022). The accuracy rate, sensitivity, specificity, and the positive and negative predictive values for the differential diagnosis of the diffuse-type carcinoma from the intestinal-type carcinoma were 94.5%, 94.1%, 94.7%, 88.9% and 97.3%, respectively. IHb is useful for making quantitative measurement of the endoscopic color in the intramucosal gastric carcinoma, and the C/N ratio by using the IHb would be helpful for distinguishing the diffuse-type carcinoma from the intestinal-type carcinoma
How intramolecular hydrogen bonding (IHB) controls the C-ON bond homolysis in alkoxyamines
International audienceRecent amazing results (Nkolo et al., Org. Biomol. Chem., 2017, 6167) on the effect of solvents and polarity on the C-ON bond homolysis rate constants kd of alkoxyamine R1R2NOR3 led us to re-investigate the antagonistic effect of intramolecular hydrogen-bonding (IHB) on kd. Here, IHB is investigated both in the nitroxyl fragment R1R2NO and in the alkyl fragment R-3, as well as between fragments, that is, the donating group on the alkyl fragment and the accepting group on the nitroxyl fragment, and conversely. It appears that IHB between fragments (inter IHB) strikingly decreases the homolysis rate constant kd, whereas IHB within the fragment (intra IHB) moderately increases kd. For one alkoxyamine, the simultaneous occurrence of IHB within the nitroxyl fragment and between fragments is reported. The protonation effect is weaker in the presence than in the absence of IHB. A moderate solvent effect is also observed
Cell cycle perturbations and apoptosis induced by isohomohalichondrin B (IHB), a natural marine compound
Isohomohalichondrin B (IHB), a novel marine compound with anti-tumoral activity, extracted from the Lissodendorix sponge, inhibits GTP binding to tubulin, preventing microtubule assembly. Cell cycle perturbations and apoptosis induced by IHB were investigated on selected human cancer cell lines by using flow cytometric and biochemical techniques. Monoparameter flow cytometric analysis showed that 1 h IHB exposure caused a delayed progression through S-phase, a dramatic block in G2M phase of the cell cycle and the appearance of tetraploid cell population in LoVo, LoVo/DX, MOLT-4 and K562 cells. At 24 h after IHB exposure, the majority of cells blocked in G2M were in prophase as assessed by morphological analysis and by the fact that they expressed high levels of cyclin A/cdc2 and cyclin B1/cdc2. At 48 h, all cells were tetraploid as assessed by biparameter cyclin A/DNA and cyclin B1/DNA content analysis. Apoptotic death was detected in both leukaemic MOLT-4 and K562 cells, which express wild-type and mutated p53 respectively, when the cells were blocked in mitotic prophase. In conclusion, IHB is a novel potent anti-tumour drug that causes delayed S-phase progression, mitotic block, tetraploidy and apoptosis in cancer cell lines. © 1999 Cancer Research Campaig
An Internet Heartbeat
Obtaining sound inferences over remote networks via active or passive
measurements is difficult. Active measurement campaigns face challenges of
load, coverage, and visibility. Passive measurements require a privileged
vantage point. Even networks under our own control too often remain poorly
understood and hard to diagnose. As a step toward the democratization of
Internet measurement, we consider the inferential power possible were the
network to include a constant and predictable stream of dedicated lightweight
measurement traffic. We posit an Internet "heartbeat," which nodes periodically
send to random destinations, and show how aggregating heartbeats facilitates
introspection into parts of the network that are today generally obtuse. We
explore the design space of an Internet heartbeat, potential use cases,
incentives, and paths to deployment
Static Characterization of InAs/AlGaAs Broadband Self-Assembled Quantum Dot Lasers
The static-characteristics of InAs/AlGaAs broadband self-assembled quantum-dot laser diodes (SAQD-LDs) have been studied to solve the rate equations numerically using fourth-order Runge-Kutta method. Energy level, size, and composition distributions of the InAs/AlGaAs broadband quantum-dots (QDs) are considered and their effects on Static-characteristics are investigated. Simulated results of static-characteristics show that nonlinearity appears in light-current characteristics whereas homogeneous broadening (HB) becomes equal to inhomogeneous broadening (IHB). Slope-efficiency increases as the HB heightens up to the IHB. Exceeding the HB from IHB results in degradation of light-current characteristics. In fact, InAs/AlGaAs broadband SAQD-LD has the best performance when HB is equal to IHB. Light-current characteristics degrade and threshold current increases as the IHB enhances. We also investigate the effects of QD coverage on the laser performance and show that there is an optimum QD coverage in which the SAQD-LD operates with lowest possible threshold current and maximum output power as whatever the QD coverage enhances from that optimum amount, the threshold current increases and slope efficiency decreases.
Deviation from tri-bimaximal mixings in two types of inverted hierarchical neutrino mass models
An attempt is made to explore the possibility for deviations of solar mixing
angle () from tri-bimaximal mixings, without sacrificing the
predictions of maximal atmospheric mixing angle () and zero
reactor angle (). We find that the above conjecture can be
automatically realised in the inverted hierarchical neutrino mass model having
2-3 symmetry, in the basis where charged lepton mass matrix is diagonal. For
the observed ranges of and \bigtriangleup m^2_{23],
we calculate the predictions on for
different input values of the parameters in the neutrino mass matrix. We also
observe a possible crossing over from one type of inverted hierarchical model
having same CP parity (Type-IHA) to other type having opposite CP parity
(Type-IHB). Such neutrino mass matrices can be obtained from the canonical
seesaw formula using diagonal form of Dirac neutrino mass matrix and
non-diagonal texture of right-handed Majorana mass matrix, and may have
important implications in model building using discrete as well as non-abelian
symmetry groups.Comment: 13 pages, 7 figure
The number of the Gabriel-Roiter measures admitting no direct predecessors over a wild quiver
A famous result by Drozd says that a finite-dimensional
representation-infinite algebra is of either tame or wild representation type.
But one has to make assumption on the ground field. The Gabriel-Roiter measure
might be an alternative approach to extend these concepts of tame and wild to
arbitrary artin algebras. In particular, the infiniteness of the number of GR
segments, i.e. sequences of Gabriel-Roiter measures which are closed under
direct predecessors and successors, might relate to the wildness of artin
algebras. As the first step, we are going to study the wild quiver with three
vertices, labeled by , and , and one arrow from to and two
arrows from to . The Gabriel-Roiter submodules of the indecomposable
preprojective modules and quasi-simple modules , are
described, where is a Kronecker module and is the
Auslander-Reiten translation. Based on these calculations, the existence of
infinitely many GR segments will be shown. Moreover, it will be proved that
there are infinitely many Gabriel-Roiter measures admitting no direct
predecessors
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