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1.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(1 Pt 1): 011405, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18351855

RESUMO

The multifractal spectrum f(alpha) characterizing the scaling properties of the growth probability on the boundary of radial diffusion-limited aggregates is known to exhibit strong finite size effects. We demonstrate that there exists a correlation between these finite size effects and those present in measurements of the angular width of the fjords which lie between the principal cluster arms. We subsequently conclude that it is the evolution in the global structure of the clusters which is responsible for the slow convergence in f(alpha) and discuss how this global structure induces a phase transition in f(alpha).

2.
Ir J Med Sci ; 186(4): 981-987, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27796667

RESUMO

BACKGROUND: Systemic Inflammatory Response Syndrome (SIRS) and sepsis remain leading causes of death. Despite many similarities, the two entities are very distinct clinically and immunologically. T-Lymphocytes play a key pivotal role in the pathogenesis and ultimately outcome following both SIRS and sepsis. Integrins are essential in the trafficking and migration of lymphocytes. They also serve vital roles in efficient wound healing and clearance of infections. Here, we investigate whether integrin expression, specifically ß1 (CD29) and ß2 (CD18), are disrupted in SIRS and sepsis, and assess differences in integrin expression between these two critically ill clinical categories. METHODS: T-Lymphocytes were isolated from whole blood collected from ICU patients exhibiting SIRS or sepsis. Samples were analyzed for CD18 (ß2) and CD29 (ß1) on CD3+ T cells through flow cytometry. Septic patients were stratified into either exclusively abdominal or non-abdominal sources of sepsis. RESULTS: CD18 was almost ubiquitously expressed on CD3+ T cells irrespective of clinical condition. However, CD29 (ß1 integrin) was lowest in SIRS patients (20.4% of CD3+ T cells) when compared with either septic patients (35.5%) or healthy volunteers (54.1%). Furthermore, there was evidence of compartmentalization in septic patients, where abdominal sources had a greater percentage of CD3+CD29+ T cells (41.7%) when compared with those with non-abdominal sources (29.5%). CONCLUSION: Distinct differences in T-cell integrin expression exists between patients in SIRS versus sepsis, as well as relative to the source of sepsis. Further work is needed to understand cause and effect relative to the progression from SIRS into sepsis.


Assuntos
Integrinas/metabolismo , Sepse/sangue , Síndrome de Resposta Inflamatória Sistêmica/sangue , Linfócitos T/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
FEBS Lett ; 415(3): 303-7, 1997 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-9357988

RESUMO

Deletion mutagenesis studies have suggested that there are two domains within APP which bind heparan sulphate. These domains have been cloned and expressed in the yeast Pichia pastoris. Both recombinant proteins bound to heparin. One domain (APP316-447) was further characterised by binding studies with peptides encompassing this region. Peptides homologous to APP316-346 and APP416-447 were found to bind heparin. Circular dichroism studies show that APP416-447 shifted towards an alpha-helical conformation in the presence of heparin. This study suggests that heparin-binding domains may lie within regions high in alpha-helical structure.


Assuntos
Precursor de Proteína beta-Amiloide/genética , Heparina/metabolismo , Estrutura Secundária de Proteína , Doença de Alzheimer , Precursor de Proteína beta-Amiloide/química , Sítios de Ligação , Western Blotting , Cromatografia de Afinidade , Dicroísmo Circular , Clonagem Molecular , Escherichia coli/genética , Expressão Gênica , Humanos , Mutagênese , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Deleção de Sequência
4.
Ann N Y Acad Sci ; 908: 226-43, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10911962

RESUMO

Several lines of evidence support the view that the bioenergetic function of the mitochondria in postmitotic tissue deteriorates during normal aging. Skeletal muscle is one such tissue that undergoes age-related fiber loss and atrophy and an age-associated rise in the number of cytochrome c oxidase (COX) deficient fibers. With such metabolic pressure placed on skeletal muscle it would be an obvious advantage to supplement the cellular requirement for energy by up-regulating glycolysis, and alternative pathway for energy synthesis. Analysis of rat skeletal muscle utilizing antibodies directed against key enzymes involved in glycolysis has provided evidence of an age-associated increase in the enzymes involved in glycolysis. Fructose-6-phosphate kinase, aldolase, glyceraldehyde-3-phosphate dehydrogenase, and pyruvate kinase protein levels appeared to increase in the soleus, gracilis, and quadriceps muscle from aged rats. The increase in the level of these proteins appeared to correlate to a corresponding decrease in the amount of cytochrome c oxidase protein measured in the same tissue. Together these results are interpreted to represent a general upregulation of glycolysis that occurs in response to the age-associated decrease in mitochondrial energy capacity. Mitochondrial DNA (mtDNA) damage and mutations may accumulate with advancing age until they reach a threshold level were they impinge on the bioenergy capacity of the cell or tissue. Evidence indicates that mtDNA from the skeletal muscle of both aged rats and humans not only undergoes changes at the nucleotide sequence level (mutations and DNA damage), but also undergoes modifications at the tertiary level to generate unique age-related conformational mtDNA species. One particular age-related conformational form was only detected in aged rat tissues with high demands on respiration, specifically in heart, kidney, soleus muscle, and, to a lesser extent, the quadriceps muscle. The age-related form was not detected in gracilis muscle which is predominantly dependent upon glycolysis with regard to its energy requirements. Finally, a comprehensive hypothesis is presented that features the stochastic nature of the mitochondrial system. The basis of the hypothesis is that a dynamic relationship exists between endogenous mutagen production, DNA repair, mtDNA turnover, and nuclear control of mtDNA copy number and that age-associated changes in the dynamics of this relationship lead to a loss of functional full-length mtDNA that eventually leads to bioenergy decline.


Assuntos
Envelhecimento/genética , DNA Mitocondrial , Animais , Glicólise , Humanos , Mutação , Conformação de Ácido Nucleico , Ratos , Processos Estocásticos
5.
Resuscitation ; 39(1-2): 81-4, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9918452

RESUMO

Advanced life support (ALS) requires several different skills and the recall of complex information. The personal computer is an ideal tool for the teaching of factual information. We have developed a computer programme that simulates a variety of cardiac arrest scenarios. Its aim is to communicate specialist knowledge to junior staff in a challenging and entertaining way. Each scenario has a real time ECG, clinical signs of the simulated patient, blood pressure, oxygen saturation and temperature. Arterial blood samples can be analysed and the medical record can be reviewed. Interventions available include defibrillation, intubation, fluid and drug therapy. Built-in variation means that repeating a scenario may lead to different patient behaviour. An important part of the programme is the intelligent debriefing of the user after each patient. Each action elicits a comment that is based upon the current European Resuscitation Council guidelines. This is then hyperlinked to an extensive help file that includes the text of the guidelines, diagrams, pictures and algorithms that aid the user in the learning of ALS skills in association with existing teaching programmes. ResusSim 98 runs under Windows 3.1, Windows 95/98 and Windows NT 4.0.


Assuntos
Simulação por Computador , Parada Cardíaca/terapia , Cuidados para Prolongar a Vida , Ressuscitação/educação , Humanos , Microcomputadores
6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 70(1 Pt 2): 015203, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15324116

RESUMO

We propose an efficient procedure for numerically evolving the quantum dynamics of delta-kicked harmonic oscillator. The method allows for longer and more accurate simulations of the system as well as a simple procedure for calculating the system's Floquet eigenstates and quasienergies. The method is used to examine the dynamical behavior of the system in cases where the ratio of the kicking frequency to the system's natural frequency is both rational and irrational.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 63(1 Pt 1): 011109, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11304236

RESUMO

In this paper we study a binary random multiplicative cascade. Specifically, the cascade is used to produce and study left-sided multifractal random measures. Extensive numerical simulations of the random cascade process were undertaken and f(alpha) spectra obtained and compared with the analytical results. We believe that this model and approach can serve as a simple and fundamental tool in the analysis and understanding of physical systems possessing an underlying multiplicative structure.

8.
Percept Mot Skills ; 45(1): 69-70, 1977 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-561943

RESUMO

This paper describes a small apparatus for demonstrating the phi phenomenon and the autokinetic effect and provides circuit diagrams whereby the apparatus may be constructed.


Assuntos
Eletrônica/instrumentação , Ilusões , Humanos
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(2 Pt 1): 021407, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22463212

RESUMO

We examine the branch structure of radial diffusion-limited aggregation (DLA) clusters for evidence of multifractality. The lacunarity of DLA clusters is measured and the generalized dimensions D(q) of their mass distribution is estimated using the sandbox method. We find that the global n-fold symmetry of the aggregates can induce anomalous scaling behavior into these measurements. However, negating the effects of this symmetry, standard scaling is recovered.


Assuntos
Coloides/química , Difusão , Fractais , Modelos Químicos , Modelos Moleculares , Modelos Estatísticos , Simulação por Computador
10.
Ir J Med Sci ; 178(4): 519-21, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18574561

RESUMO

Appendiceal diverticulitis is a rare presentation, often presenting outside of the classical age grouping for appendicitis. We describe a case of appendiceal diverticulitis and issue a cautionary note in the management of patients with atypical features of right lower quadrant pain. In light of its clinical course the finding of a non-inflamed appendiceal diverticulum should prompt one to consider incidental appendicectomy. We also review the literature on appendiceal diverticulitis.


Assuntos
Apendicite/diagnóstico , Apêndice/patologia , Diverticulite/diagnóstico , Apendicectomia , Apendicite/cirurgia , Apêndice/cirurgia , Diagnóstico Diferencial , Diverticulite/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade
11.
Phys Rev Lett ; 100(6): 062001, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18352457

RESUMO

We report measurements of the exclusive cross section for e(+)e(-)-->D(0)D(-)pi(+) over the center-of-mass energy range 4.0 GeV to 5.0 GeV with initial-state radiation and the first observation of the decay psi(4415)-->D(0)D(-)pi(+). From a study of the resonant substructure in psi(4415) decay we conclude that the psi(4415)-->D(0)D(-)pi(+) decay is dominated by psi(4415)-->DD(2)(*)(2460). We obtain B(psi(4415)-->D(0)D(-)pi(nonresonant)(+))/B(psi(4415)-->DD(2)(*)(2460)-->D(0)D(-)pi(+))<0.22 at 90% C.L. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of 673 fb(-1).

12.
Phys Rev Lett ; 100(9): 092001, 2008 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-18352700

RESUMO

We report the observation of a new DsJ meson produced in B+-->D0DsJ-->D0D0K+. This state has a mass of M=2708+/-9(-10)(+11) MeV/c2, a width Gamma=108+/-23(-31)(+36) MeV/c2 and a 1- spin-parity. The statistical significance of this observation is 8.4 sigma. The results are based on an analysis of 449 x 10(6) BB events collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.

13.
Phys Rev Lett ; 100(11): 112001, 2008 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-18517777

RESUMO

We report the first observation of e;{+}e;{-}-->Upsilon(1S)pi;{+}pi;{-}, Upsilon(2S)pi;{+}pi;{-}, and first evidence for e;{+}e;{-}-->Upsilon(3S)pi;{+}pi;{-}, Upsilon(1S)K+K-, near the peak of the Upsilon(5S) resonance at sqrt[s] approximately 10.87 GeV. The results are based on a data sample of 21.7 fb;{-1} collected with the Belle detector at the KEKB e;{+}e;{-} collider. Attributing the signals to the Upsilon(5S) resonance, the partial widths Gamma(Upsilon(5S)-->Upsilon(1S)pi;{+}pi;{-})=0.59+/-0.04(stat)+/-0.09(syst) MeV and Gamma(Upsilon(5S)-->Upsilon(2S)pi;{+}pi;{-})=0.85+/-0.07(stat)+/-0.16(syst) MeV are obtained from the observed cross sections. These values exceed by more than 2 orders of magnitude the previously measured partial widths for dipion transitions between lower Upsilon resonances.

14.
Phys Rev Lett ; 100(12): 121601, 2008 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-18517853

RESUMO

We report a measurement of the CP-violating parameters in B;{0}-->K_{S}{0}K_{S}{0} decays based on a data sample of 657x10{6} BB[over ] pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e;{+}e{-} collider. In this Letter, one neutral B meson is fully reconstructed in the B;{0}-->K_{S}{0}K_{S}{0} decay mode, and the flavor of the accompanying B meson is identified by its decay products. The CP-violating parameters are measured from the asymmetry in the distributions of the proper-time interval between the two B decays: S_K_{S}{0}K_{S}{0}}=-0.38_{-0.77}{+0.69}(stat)+/-0.09(syst) and A_{K_{S}{0}K_{S}{0}}=-0.38+/-0.38(stat)+/-0.05(syst).

15.
Phys Rev Lett ; 100(12): 121801, 2008 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-18517854

RESUMO

We search for the radiative penguin decays B_{s}{0}-->varphigamma and B_{s}{0}-->gammagamma in a 23.6 fb{-1} data sample collected at the Upsilon(5S) resonance with the Belle detector at the KEKB e{+}e{-} asymmetric-energy collider. We observe for the first time a radiative penguin decay of the B_{s}{0} meson in the B_{s}{0}-->varphigamma mode and we measure B(B_{s}{0}-->varphigamma)=(57_{-15}{+18}(stat)-11+12(syst))x10{-6}. No significant B_{s}{0}-->gammagamma signal is observed and we set a 90% confidence level upper limit of B(B_{s}{0}-->gammagamma)<8.7x10{-6}.

16.
Phys Rev Lett ; 100(14): 142001, 2008 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-18518023

RESUMO

A distinct peak is observed in the pi +/- psi' invariant mass distribution near 4.43 GeV in B-->K pi +/- psi' decays. A fit using a Breit-Wigner resonance shape yields a peak mass and width of M=4433+/-4(stat)+/-2(syst) MeV and Gamma=45-13+18(stat)-13+30(syst) MeV. The product branching fraction is determined to be B(B 0-->K -/+Z+/-(4430)) x B(Z+/-(4430)-->pi+/-psi')=(4.1+/-1.0(stat)+/-1.4(syst)) x 10(-5), where Z+/-(4430) is used to denote the observed structure. The statistical significance of the observed peak is 6.5 sigma. These results are obtained from a 605 fb(-1) data sample that contains 657 x 10(6) BB pairs collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider.

17.
Phys Rev Lett ; 100(20): 202001, 2008 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-18518525

RESUMO

We report a study of the processes e+e- -->J/psiD*D[over](*). In J/psiD*D[over]* we observe a significant enhancement in the D*D[over]* invariant mass spectrum, which we interpret as a new charmoniumlike state and denote X(4160). The X(4160) parameters are M=(4156(-20)+25+/-15) MeV/c2 and Gamma=(139(-61)+111+/-21) MeV. We also report a new measurement of the X(3940) mass and width: M=(3942(-6)+7+/-6) MeV/c2 and Gamma=(37(-15)+26+/-8) MeV. The analysis is based on a 693 fb(-1) data sample recorded near the Upsilon(4S) resonance by the Belle detector at the KEKB asymmetric-energy collider.

18.
Phys Rev Lett ; 100(24): 241801, 2008 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-18643570

RESUMO

We present a measurement of the branching fraction B(D{s}{+}-->mu{+}nu{mu}) using a 548 fb{-1} data sample collected by the Belle experiment at the KEKB e{+}e{-} collider. The D{s} momentum is determined by reconstruction of the system recoiling against DKgammaX in events of the type e{+}e{-}-->D{s}{*}DKX, D{s}{*}-->D{s}gamma, where X represents additional pions or photons from fragmentation. This full-reconstruction method provides high resolution in the neutrino momentum and thus good background separation, equivalent to that achieved by experiments at the tau-charm factories. We obtain the branching fraction B(D{s}{+}-->mu{+}nu{mu})=[6.44+/-0.76(stat)+/-0.57(syst)]x10{-3}, implying a D{s} decay constant of f{D{s}}=[275+/-16(stat)+/-12(syst)] MeV.

19.
Phys Rev Lett ; 100(25): 251801, 2008 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-18643652

RESUMO

Using a 492 fb{-1} data sample collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e{+}e{-} collider, we observe the decay B{0}-->ppK*0 with a branching fraction of (1.18{-0.25}{+0.29}(stat)+/-0.11(syst))x10{-6}. We study the decay dynamics of B{0}-->ppK*0 and compare with B{+}-->ppK*+. The K*0 meson is found to be almost 100% polarized (with a fraction of (101+/-13+/-3)% in the helicity zero state), while the K*+ meson has a (32+/-17+/-9)% fraction in the helicity zero state. The direct CP asymmetries for B{0}-->ppK*0 and B{+}-->ppK*+ are measured to be -0.08+/-0.20+/-0.02 and -0.01+/-0.19+/-0.02, respectively. In addition, we report improved measurements of the branching fractions B(B{+}-->ppK*+)=(3.38{-0.60}{+0.73}+/-0.39)x10{-6} and B(B{0}-->ppK{0})=(2.51{-0.29}{+0.35}+/-0.21)x10{-6}, which supersede our previous measurements.

20.
Phys Rev Lett ; 100(2): 021602, 2008 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-18232853

RESUMO

We report the first measurement of CP-violation parameters in B0-->rho0gamma decays based on a data sample of 657x10(6)BB pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain the time-dependent and direct CP-violating parameters, Srho0gamma=-0.83+/-0.65(stat)+/-0.18(syst) and Arho0gamma=-0.44+/-0.49(stat)+/-0.14(syst), respectively.

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