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1.
Acta Paediatr ; 112(11): 2352-2358, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37505925

RESUMO

AIM: We introduced routine probiotic supplementation (RPS) of preterm infants in June 2012. We previously reported that RPS reduced the incidence of necrotising enterocolitis (NEC) and mortality in such infants. In this study, we assessed if the benefits of RPS were sustained for infants in the current era. METHOD: We compared the outcomes of preterm infants in recent epoch 3 (RPS, 1st June 2014 to 31st December 2019) versus epoch 2 (RPS, 1st June 2012 to 31st May 2014) and epoch 1 (no RPS, 1st December 2008 to 30th November 2010). Multiple logistic and Cox regression models were used to compare the outcomes. RESULTS: There were 645 infants in epoch 1, 712 in epoch 2 and 1715 in epoch 3. Age at full feeds was significantly lower in epoch 3 vs. 2 and epoch 3 vs. 1 in infants <28 weeks of gestation. NEC and late-onset sepsis (LOS) were significantly lower in epoch 3 vs. 1 in infants <28 weeks. LOS and age at full feeds were significantly lower in epoch 3 vs. 2 and epoch 3 vs. 1 in infants with gestation 28 to 32 weeks. CONCLUSION: The benefits associated with RPS were sustained during epoch 3.


Assuntos
Enterocolite Necrosante , Doenças do Prematuro , Probióticos , Sepse , Lactente , Recém-Nascido , Humanos , Recém-Nascido Prematuro , Probióticos/uso terapêutico , Incidência , Doenças do Prematuro/epidemiologia , Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/prevenção & controle , Recém-Nascido de muito Baixo Peso
2.
Chaos ; 30(11): 113134, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33261366

RESUMO

We observe the presence of infinitely fine-scaled alternations within the performance landscape of reservoir computers aimed for chaotic data forecasting. We investigate the emergence of the observed structures by means of variations of the transversal stability of the synchronization manifold relating the observational and internal dynamical states. Finally, we deduce a simple calibration method in order to attenuate the thus evidenced performance uncertainty.

3.
Phys Rev Lett ; 118(7): 075002, 2017 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-28256868

RESUMO

The wake-mediated propulsion of an "extra" particle in a channel of two neighboring rows of a two-dimensional plasma crystal, observed experimentally by Du et al. [Phys. Rev. E 89, 021101(R) (2014)PRESCM1539-375510.1103/PhysRevE.89.021101], is explained in simulations and theory. We use the simple model of a pointlike ion wake charge to reproduce this intriguing effect in simulations, allowing for a detailed investigation and a deeper understanding of the underlying dynamics. We show that the nonreciprocity of the particle interaction, owing to the wake charges, is responsible for a broken symmetry of the channel that enables a persistent self-propelled motion of the extra particle. We find good agreement of the terminal extra-particle velocity with our theoretical considerations and with experiments.

4.
Phys Rev E ; 107(6-1): 064603, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37464622

RESUMO

In this experimental paper, we demonstrate that turbulence can develop in a fluid system with background damping. For that purpose, we analyze dust acoustic waves, self-excited in a fluid complex plasma where the motion of individual microparticles was recorded with a high-speed video camera. We use the Wiener-Khinchin theorem to calculate the kinetic spectrum during different phases of the highly nonlinear periodic wave motion and show that a turbulent cascade develops at the phases of highest particle compression. We demonstrate that the energy cascade occurs despite the presence of a damping force due to the background neutral gas.

5.
Phys Rev Lett ; 109(14): 144101, 2012 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-23083244

RESUMO

The method of surrogates is one of the key concepts of nonlinear data analysis. Here, we demonstrate that commonly used algorithms for generating surrogates often fail to generate truly linear time series. Rather, they create surrogate realizations with Fourier phase correlations leading to nondetections of nonlinearities. We argue that reliable surrogates can only be generated, if one tests separately for static and dynamic nonlinearities.

6.
Phys Rev Lett ; 106(15): 155001, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21568565

RESUMO

Dedicated experiments with strongly coupled complex plasmas in external electric fields were carried out under microgravity conditions using the PK-4 dc discharge setup. The focus was put on the comparative analysis of the formation of stringlike anisotropic structures due to reciprocal (hamiltonian) and nonreciprocal (non-hamiltonian) interactions between microparticles (induced by ac and dc fields, respectively). The experiments complemented by numerical simulations demonstrate that the responses of complex plasmas in these two regimes are drastically different. It is suggested that the observed difference is a manifestation of intrinsic thermodynamic openness of driven strongly coupled systems.

7.
Phys Rev E ; 104(4-2): 045212, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34781487

RESUMO

We investigated the self-excited as well as optogalvanically stimulated heartbeat instability in RF discharge complex plasma. Three video cameras measured the motion of the microparticles, the plasma emission, and the laser-induced fluorescence simultaneously. Comprehensive studies of the optogalvanic control of the heartbeat instability revealed that the microparticle suspension can be stabilized by a continuous laser, whereas a modulated laser beam induces the void contraction either transiently or resonantly. The resonance occurred when the laser modulation frequency coincided with the frequency of small breathing oscillations of the microparticle suspension, which are known to be a prerequisite to the heartbeat instability. Based on the experimental results we suggest that the void contraction during the instability is caused by an abrupt void transition from the dim to the bright regime [Pikalev et al., Plasma Sources Sci. Technol. 30, 035014 (2021)PSTEEU0963-025210.1088/1361-6595/abe0a2]. In the bright regime, a time-averaged electric field at the void boundary heats the electrons causing bright plasma emission inside the void. The dim void has much lower electric field at the boundary and exhibits therefore no emission feature associated with it.

8.
Osteoporos Int ; 21(9): 1553-64, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19859642

RESUMO

SUMMARY: The standard diagnostic technique for assessing osteoporosis is dual X-ray absorptiometry (DXA) measuring bone mass parameters. In this study, a combination of DXA and trabecular structure parameters (acquired by computed tomography [CT]) most accurately predicted the biomechanical strength of the proximal femur and allowed for a better prediction than DXA alone. INTRODUCTION: An automated 3D segmentation algorithm was applied to determine specific structure parameters of the trabecular bone in CT images of the proximal femur. This was done to evaluate the ability of these parameters for predicting biomechanical femoral bone strength in comparison with bone mineral content (BMC) and bone mineral density (BMD) acquired by DXA as standard diagnostic technique. METHODS: One hundred eighty-seven proximal femur specimens were harvested from formalin-fixed human cadavers. BMC and BMD were determined by DXA. Structure parameters of the trabecular bone (i.e., morphometry, fuzzy logic, Minkowski functionals, and the scaling index method [SIM]) were computed from CT images. Absolute femoral bone strength was assessed with a biomechanical side-impact test measuring failure load (FL). Adjusted FL parameters for appraisal of relative bone strength were calculated by dividing FL by influencing variables such as body height, weight, or femoral head diameter. RESULTS: The best single parameter predicting FL and adjusted FL parameters was apparent trabecular separation (morphometry) or DXA-derived BMC or BMD with correlations up to r = 0.802. In combination with DXA, structure parameters (most notably the SIM and morphometry) added in linear regression models significant information in predicting FL and all adjusted FL parameters (up to R(adj) = 0.872) and allowed for a significant better prediction than DXA alone. CONCLUSION: A combination of bone mass (DXA) and structure parameters of the trabecular bone (linear and nonlinear, global and local) most accurately predicted absolute and relative femoral bone strength.


Assuntos
Fêmur/fisiopatologia , Osteoporose/diagnóstico , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Densidade Óssea/fisiologia , Feminino , Fêmur/diagnóstico por imagem , Fêmur/patologia , Cabeça do Fêmur/diagnóstico por imagem , Cabeça do Fêmur/fisiopatologia , Colo do Fêmur/diagnóstico por imagem , Colo do Fêmur/fisiopatologia , Lógica Fuzzy , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Osteoporose/patologia , Osteoporose/fisiopatologia , Estresse Mecânico , Tomografia Computadorizada por Raios X/métodos
9.
Phys Rev Lett ; 105(4): 045001, 2010 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-20867851

RESUMO

Using experiments and combining theory and computer simulations, we show that binary complex plasmas are particularly good model systems to study the kinetics of fluid-fluid demixing at the "atomistic" (individual particle) level. The essential parameters of interparticle interactions in complex plasmas, such as the interaction range(s) and degree of nonadditivity, can be varied significantly, which allows systematic investigations of different demixing regimes. The critical role of competition between long-range and short-range interactions at the initial stage of the spinodal decomposition is discussed.

10.
Phys Rev E ; 97(5-1): 053201, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29906865

RESUMO

Experiments of the recrystallization processes in two-dimensional complex plasmas are analyzed to rigorously test a recently developed scale-free phase transition theory. The "fractal-domain-structure" (FDS) theory is based on the kinetic theory of Frenkel. It assumes the formation of homogeneous domains, separated by defect lines, during crystallization and a fractal relationship between domain area and boundary length. For the defect number fraction and system energy a scale-free power-law relation is predicted. The long-range scaling behavior of the bond-order correlation function shows clearly that the complex plasma phase transitions are not of the Kosterlitz, Thouless, Halperin, Nelson, and Young type. Previous preliminary results obtained by counting the number of dislocations and applying a bond-order metric for structural analysis are reproduced. These findings are supplemented by extending the use of the bond-order metric to measure the defect number fraction and furthermore applying state-of-the-art analysis methods, allowing a systematic testing of the FDS theory with unprecedented scrutiny: A morphological analysis of lattice structure is performed via Minkowski tensor methods. Minkowski tensors form a complete family of additive, motion covariant and continuous morphological measures that are sensitive to nonlinear properties. The FDS theory is rigorously confirmed and predictions of the theory are reproduced extremely well. The predicted scale-free power-law relation between defect fraction number and system energy is verified for one more order of magnitude at high energies compared to the inherently discontinuous bond-order metric. It is found that the fractal relation between crystalline domain area and circumference is independent of the experiment, the particular Minkowski tensor method, and the particular choice of parameters. Thus, the fractal relationship seems to be inherent to two-dimensional phase transitions in complex plasmas. Minkowski tensor analysis turns out to be a powerful tool for investigations of crystallization processes. It is capable of revealing nonlinear local topological properties, however, still provides easily interpretable results founded on a solid mathematical framework.

11.
Phys Rev E ; 95(4-1): 041201, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28505869

RESUMO

We study a complex plasma under microgravity conditions that is first stabilized with an oscillating electric field. Once the stabilization is stopped, the so-called heartbeat instability develops. We study how the kinetic energy spectrum changes during and after the onset of the instability and compare with the double cascade predicted by Kraichnan and Leith for two-dimensional turbulence. The onset of the instability manifests clearly in the ratio of the reduced rates of cascade of energy and enstrophy and in the power-law exponents of the energy spectra.

12.
Phys Rev E ; 94(1-1): 013201, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27575224

RESUMO

A molecular dynamics simulation of the demixing process of a binary complex plasma is analyzed and the role of distinct interaction potentials is discussed by using morphological Minkowski tensor analysis of the minority phase domain growth in a demixing simulated binary complex plasma. These Minkowski tensor methods are compared with previous results that utilized a power spectrum method based on the time-dependent average structure factor. It is shown that the Minkowski tensor methods are superior to the previously used power-spectrum method in the sense of higher sensitivity to changes in domain size. By analysis of the slope of the temporal evolution of Minkowski tensor measures, qualitative differences between the case of particle interaction with a single length scale compared to particle interactions with two different length scales (dominating long-range interaction) are revealed. After proper scaling the graphs for the two length scale scenarios coincide, pointing toward universal behavior. The qualitative difference in demixing scenarios is evidenced by distinct demixing behavior: in the long-range dominated cases demixing occurs in two stages. At first, neighboring particles agglomerate, then domains start to merge in cascades. However, in the case of only one interaction length scale only agglomeration but no merging of domains can be observed. Thus, Minkowski tensor analysis is likely to become a useful tool for further investigation of this (and other) demixing processes. It is capable to reveal (nonlinear) local topological properties, probing deeper than (linear) global power-spectrum analysis, however, still providing easily interpretable results founded on a solid mathematical framework.

13.
Phys Rev E ; 93(1): 013204, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26871180

RESUMO

The spectral asymmetry of the wave-energy distribution of dust particles during mode-coupling-induced melting, observed for the first time in plasma crystals by Couëdel et al. [Phys. Rev. E 89, 053108 (2014)PLEEE81539-375510.1103/PhysRevE.89.053108], is studied theoretically and by molecular-dynamics simulations. It is shown that an anisotropy of the well confining the microparticles selects the directions of preferred particle motion. The observed differences in intensity of waves of opposed directions are explained by a nonvanishing phonon flux. Anisotropic phonon scattering by defects and Umklapp scattering are proposed as possible reasons for the mean phonon flux.

14.
Int J Biol Macromol ; 93(Pt A): 1161-1167, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27667539

RESUMO

In this investigation an attempt has been made to characterize and identify Lysinibacillus sp. 3HHX by 16S-rDNA sequencing. The bacterium exhibited occurrence of PHAs granules on an average 11±1 per cell of 1.0µm length and breadth 0.72µm, revealed from TEM studies. Under optimized condition, 4.006gm/L of PHAs was extracted using hypochlorite digestion and multi-solvent extraction process. PhaC gene of ∼540bp and higher PHA synthase activity was detected at 48h of cultivation. The extracted PHAs was structurally characterized by GC-MS and 1H NMR reported to be P(3HB-co-3HDD-co-3HTD) and amorphous in nature with 112°C melting point, -11.0°C glass transition point and 114.76°C decomposition temperature detected by DSC & TGA respectively. The C/O of biopolymer disc was 1:65 as revealed from C1s and O1s spectra of XPS, that was completely biodegradable within 30 days. This biopolymer was observed to be non-cytotoxic to NIH 3T3 mouse fibroblast cells. The report is of its kind in establishing the abilities of Lysinibacillus sp. 3HHX for non-growth associated PHA co-polymer production. Moreover the biocompatible and biodegradable nature of the biopolymer conferred to its substantial biomedical applications.


Assuntos
Bacillaceae/metabolismo , Fermentação , Poli-Hidroxialcanoatos/biossíntese , Poli-Hidroxialcanoatos/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Imersão , Camundongos , Células NIH 3T3 , Poli-Hidroxialcanoatos/metabolismo , Poli-Hidroxialcanoatos/toxicidade , Rizosfera , Microbiologia do Solo
15.
Artigo em Inglês | MEDLINE | ID: mdl-26565155

RESUMO

It is demonstrated how to generate time series with tailored nonlinearities by inducing well-defined constraints on the Fourier phases. Correlations between the phase information of adjacent phases and (static and dynamic) measures of nonlinearities are established and their origin is explained. By applying a set of simple constraints on the phases of an originally linear and uncorrelated Gaussian time series, the observed scaling behavior of the intensity distribution of empirical time series can be reproduced. The power law character of the intensity distributions being typical for, e.g., turbulence and financial data can thus be explained in terms of phase correlations.

16.
Indian J Med Microbiol ; 33 Suppl: 93-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25657164

RESUMO

In the present investigation, anti-Candida activity of four essential oils i.e. Black cumin (Nigella sativa), Curry leaf (Murraya koienigii), Ajwain (Trachiyspirum ammi), and Betel leaf (Piper betel) were screened against four human pathogenic species of Candida viz. Candida albicans, Candida tropicalis, Candida glabrata, and Candida parapsilosis. The minimum inhibitory concentration (MIC) values of the oils ranged between 15.62 and 250 µl/ml while studied through tube dilution method. The oils retained their anti-Candida activities even after heat treatment (at 45ΊC, 60ΊC, 100ΊC for 1 hour) and also on autoclaving. Both Ajwain and Black Cumin leaf oils showed better anti-Candida activity against Candida albicans, resulting in an irreversible damage to the cells. The anti-Candida activity of these essential oils could be attributable to the membrane inhibition mechanism. The activity of the oils is reported to be microbicidal (Candida-cidal).


Assuntos
Candida/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Antifúngicos/farmacologia , Humanos , Óleos de Plantas/farmacologia , Temperatura
17.
Biosens Bioelectron ; 69: 301-6, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25771302

RESUMO

Single-cell analysis has developed into a key topic in cell biology with future applications in personalized medicine, tumor identification as well as tumor discovery (Editorial, 2013). Here we employ inkjet-like printing to isolate individual living single human B cells (Raji cell line) and load them directly into standard PCR tubes. Single cells are optically detected in the nozzle of the microfluidic piezoelectric dispenser chip to ensure printing of droplets with single cells only. The printing process has been characterized by using microbeads (10µm diameter) resulting in a single bead delivery in 27 out of 28 cases and relative positional precision of ±350µm at a printing distance of 6mm between nozzle and tube lid. Process-integrated optical imaging enabled to identify the printing failure as void droplet and to exclude it from downstream processing. PCR of truly single-cell DNA was performed without pre-amplification directly from single Raji cells with 33% success rate (N=197) and Cq values of 36.3±2.5. Additionally single cell whole genome amplification (WGA) was employed to pre-amplify the single-cell DNA by a factor of >1000. This facilitated subsequent PCR for the same gene yielding a success rate of 64% (N=33) which will allow more sophisticated downstream analysis like sequencing, electrophoresis or multiplexing.


Assuntos
Mapeamento Cromossômico/instrumentação , Periféricos de Computador , DNA/genética , Dispositivos Lab-On-A-Chip , Linfoma/patologia , Reação em Cadeia da Polimerase/instrumentação , Substitutos Sanguíneos , Linhagem Celular Tumoral , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Robótica/instrumentação
18.
Am J Med ; 60(5): 719-22, 1976 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-1020759

RESUMO

An acute coagulopathy developed in a 49 year old woman with severe liver disease after she received an infusion of prothrombin complex concentrate. The concentrate used in the infusion was subsequently studied by observing the effect of the concentrate on the partial thromboplastin times of various plasmas. The evidence suggests that activated coagulation factors, including activated factor X, were present in the concentrate, and probably played a role in initiating the acute change in the patient's coagulation status. Mechanisms whereby liver disease predisposes toward the development of such a coagulopathy are discussed. It would appear that prothrombin complex concentrates should be used in patients with liver disease only with utmost caution.


Assuntos
Coagulação Intravascular Disseminada/induzido quimicamente , Fator X/efeitos adversos , Protrombina/efeitos adversos , Alcoolismo/complicações , Anemia Hemolítica/complicações , Anemia Hemolítica/tratamento farmacológico , Fatores de Coagulação Sanguínea , Testes de Coagulação Sanguínea , Encefalopatias/complicações , Feminino , Insuficiência Cardíaca/complicações , Humanos , Hipertensão Portal/complicações , Hepatopatias/complicações , Pessoa de Meia-Idade , Protrombina/uso terapêutico , Tempo de Protrombina
19.
Am J Clin Pathol ; 74(2): 180-5, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7405896

RESUMO

In its clinical presentation, malignant histiocytosis may mimic infections or hematologic neoplasms, and pathologically it may be mistaken for Hodgkin's disease, histiocytic lymphoma, or viral lymphadenitis. The case histories of three patients in whom malignant histiocytosis clinically and pathologically simulated granulomatous diseases are reported. Erythrophagocytosis was not present in the initial bone marrow aspirates from two of the patients. One patient was considered to hve sarcoidosis or Wegener's granulomatosis; the second patient, Weber-Christian disease, and the third patient, a granulomatous disease of infectious origin. Granulomas have been found in tissues of patients who have Hodgkin's disease, but have been found only rarely in association with malignant histocytosis. An explanation for the presence of granulomas in association with malignant histiocytosis is offered: they may represent a phase in the evolution of the disease.


Assuntos
Granuloma/diagnóstico , Doenças Linfáticas/diagnóstico , Adolescente , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Granuloma/etiologia , Granulomatose com Poliangiite/diagnóstico , Humanos , Doenças Linfáticas/complicações , Doenças Linfáticas/patologia , Masculino , Paniculite Nodular não Supurativa/diagnóstico , Sarcoidose/diagnóstico
20.
Am J Clin Pathol ; 77(3): 356-9, 1982 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7072640

RESUMO

A 73-year-old man with myelodysplastic syndrome developed during the course of his illness auto-immune hemolytic anemia. The association between auto-immune hemolysis and myeloproliferative disease is extremely rare. An even more unique finding is the nature of the antibody which demonstrated single specificity against the U antigen.


Assuntos
Anemia Hemolítica Autoimune/complicações , Sistema do Grupo Sanguíneo MNSs/imunologia , Transtornos Mieloproliferativos/complicações , Idoso , Anemia Hemolítica Autoimune/imunologia , Anemia Hemolítica Autoimune/terapia , Especificidade de Anticorpos , Tipagem e Reações Cruzadas Sanguíneas , Transfusão de Sangue , Transfusão de Eritrócitos , Humanos , Masculino , Transtornos Mieloproliferativos/imunologia , Transtornos Mieloproliferativos/terapia , Transfusão de Plaquetas , Prednisona/uso terapêutico
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