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1.
Phys Rev Lett ; 126(24): 241102, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213926

RESUMO

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gµ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gµ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gµâ‰²4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

2.
Lett Appl Microbiol ; 72(1): 68-73, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32964453

RESUMO

Engineered Escherichia coli has recently been applied to produce 1,3-propanediol (1,3-PDO) from glucose. A metabolic intermediate in the production pathway, glycerol, is partially secreted into the extracellular of E. coli through a glycerol facilitator encoded by glpF, and this secretion consequently decreases 1,3-PDO production. Therefore, we aimed to determine whether disrupting the glpF gene would improve 1,3-PDO production in E. coli. The intracellular glycerol concentration in a glpF-disruptant was 7·5 times higher than in a non-disruptant. The glpF-disrupted and non-disrupted E. coli strains produced 0·26 and 0·09 g l-1 of 1,3-PDO, respectively, from 1% glucose after 72 h of cultivation. The specific growth rate (µ) and the 1,3-PDO yield from glucose (YP/S ) in the disruptant were higher than those in the non-disruptant (ΔglpF, µ = 0·08 ± 0·00 h-1 , YP/S  = 0·06 mol mol-glucose-1 ; BW25113, µ = 0·06 ± 0·00 h-1 , YP/S  = 0·02 mol mol-glucose-1 ). Disruption of the glpF gene decreased the production of the by-product, acetic acid. These results indicated that disruption of glpF increased the intracellular concentration of glycerol and consequently increased 1,3-PDO production in E. coli.


Assuntos
Aquaporinas/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Glicerol/metabolismo , Propilenoglicóis/metabolismo , Aquaporinas/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Glucose/metabolismo
3.
J Appl Microbiol ; 130(6): 1972-1980, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33064909

RESUMO

AIM: Aspergillus niger S17-5 produces two alkylitaconic acids, 9-hydroxyhexylitaconic acid (9-HHIA) and 10-hydroxyhexylitaconic acid (10-HHIA), which have cytotoxic and polymer building block properties. In this study, we characterized the production of 9-HHIA and 10-HHIA by addition of their expected precursor, caprylic acid, to a culture of A. niger S17-5, and demonstrated batch fermentation of 9-HHIA and 10-HHIA in a jar fermenter with DO-stat. METHODS AND RESULTS: Production titres of 9-HHIA and 10-HHIA from 3% glucose in a flask after 25 days cultivation were 0·35 and 1·01 g l-1 respectively. Addition of 0·22 g l-1 of caprylic acid to a suspension of resting cells of A. niger S17-5 led to 32% enhancement of total 9-HHIA and 10-HHIA production compared to no addition. No enhancement of the production of 9-HHIA or 10-HHIA by the addition of oxaloacetic acid was observed. Addition of caprylic acid to the culture at mid-growth phase was more suitable for 9-HHIA and 10-HHIA production due to less cell growth inhibition by caprylic acid. DO-stat batch fermentation with 3% glucose and 14·4 g l-1 of caprylic acid in a 1·5 l jar fermenter resulted in the production titres of 9-HHIA and 10-HHIA being 0·48 and 1·54 g l-1 respectively after 10 days of cultivation. CONCLUSIONS: Addition of caprylic acid to the culture of A. niger S17-5 enhances 9-HHIA and 10-HHIA production. SIGNIFICANCE AND IMPACT OF THE STUDY: These results suggest that 9-HHIA and 10-HHIA are synthesized with octanoyl-CoA derived from caprylic acid, and that the supply of octanoyl-CoA is a rate-limiting step in 9-HHIA and 10-HHIA production. To the best of our knowledge, this is the first report regarding the fermentation of naturally occurring itaconic acid derivatives in a jar fermenter.


Assuntos
Aspergillus niger/metabolismo , Caprilatos/metabolismo , Succinatos/metabolismo , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/crescimento & desenvolvimento , Reatores Biológicos , Caprilatos/análise , Caprilatos/farmacologia , Fermentação , Glucose/análise , Glucose/metabolismo , Succinatos/análise , Succinatos/química
4.
Living Rev Relativ ; 23(1): 3, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33015351

RESUMO

We present our current best estimate of the plausible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next several years, with the intention of providing information to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals for the third (O3), fourth (O4) and fifth observing (O5) runs, including the planned upgrades of the Advanced LIGO and Advanced Virgo detectors. We study the capability of the network to determine the sky location of the source for gravitational-wave signals from the inspiral of binary systems of compact objects, that is binary neutron star, neutron star-black hole, and binary black hole systems. The ability to localize the sources is given as a sky-area probability, luminosity distance, and comoving volume. The median sky localization area (90% credible region) is expected to be a few hundreds of square degrees for all types of binary systems during O3 with the Advanced LIGO and Virgo (HLV) network. The median sky localization area will improve to a few tens of square degrees during O4 with the Advanced LIGO, Virgo, and KAGRA (HLVK) network. During O3, the median localization volume (90% credible region) is expected to be on the order of 10 5 , 10 6 , 10 7 Mpc 3 for binary neutron star, neutron star-black hole, and binary black hole systems, respectively. The localization volume in O4 is expected to be about a factor two smaller than in O3. We predict a detection count of 1 - 1 + 12 ( 10 - 10 + 52 ) for binary neutron star mergers, of 0 - 0 + 19 ( 1 - 1 + 91 ) for neutron star-black hole mergers, and 17 - 11 + 22 ( 79 - 44 + 89 ) for binary black hole mergers in a one-calendar-year observing run of the HLV network during O3 (HLVK network during O4). We evaluate sensitivity and localization expectations for unmodeled signal searches, including the search for intermediate mass black hole binary mergers.

5.
Living Rev Relativ ; 21(1): 3, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29725242

RESUMO

We present possible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitational-wave transients, with particular focus on gravitational-wave signals from the inspiral of binary neutron star systems, which are the most promising targets for multi-messenger astronomy. The ability to localize the sources of the detected signals depends on the geographical distribution of the detectors and their relative sensitivity, and [Formula: see text] credible regions can be as large as thousands of square degrees when only two sensitive detectors are operational. Determining the sky position of a significant fraction of detected signals to areas of 5-[Formula: see text] requires at least three detectors of sensitivity within a factor of [Formula: see text] of each other and with a broad frequency bandwidth. When all detectors, including KAGRA and the third LIGO detector in India, reach design sensitivity, a significant fraction of gravitational-wave signals will be localized to a few square degrees by gravitational-wave observations alone.

6.
Diabetes Metab ; 43(5): 430-437, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28648835

RESUMO

AIM: This study evaluated the effects of a glucagon-like peptide-1 receptor agonist on gastrointestinal (GI) tract motility and residue rates by examining GI transit time and lumen using capsule endoscopy. MATERIAL AND METHODS: GI motility and lumen were assessed by capsule endoscopy before and after liraglutide administration in 14 patients with type 2 diabetes mellitus (T2DM). RESULTS: Gastric transit time in the group with diabetic neuropathy (DN) was 1:12:36±1:04:30h before liraglutide administration and 0:48:40±0:32:52h after administration (nonsignificant difference, P=0.19). Gastric transit time in the non-DN group was 1:01:30±0:52:59h before administration and 2:33:29±1:37:24h after administration (significant increase, P=0.03). Duodenal and small intestine transit time in the DN group was 4:10:34±0:25:54h before and 6:38:42±3:52:42h after administration (not significant, P=0.09) and, in the non-DN group, 3:51:03±0:53:47h before and 6:45:31±2:41:36h after administration (significant increase, P=0.03). The GI residue rate in the DN group was 32.1±24% before administration and 90.0±9.1% after administration (significant increase, P<0.001), and increased in all patients; in the non-DN group, it was 32.1±35.3% before and 78.3±23.9% after administration (significant increase, P<0.001), and also increased in all patients. CONCLUSION: Liraglutide causes delayed gastric emptying and inhibits duodenal and small intestine motility. However, these GI movement-inhibiting effects may be decreased or absent in patients with DN-associated dysautonomia.


Assuntos
Neuropatias Diabéticas/fisiopatologia , Motilidade Gastrointestinal/efeitos dos fármacos , Trânsito Gastrointestinal/efeitos dos fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Liraglutida/farmacologia , Idoso , Endoscopia por Cápsula , Humanos , Masculino , Pessoa de Meia-Idade , Álcool Feniletílico/análogos & derivados
7.
Genes Brain Behav ; 16(3): 394-403, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27762066

RESUMO

Dopamine (DA) is a neurotransmitter with conserved behavioral roles between invertebrate and vertebrate animals. In addition to its neural functions, in insects DA is a critical substrate for cuticle pigmentation and hardening. Drosophila tyrosine hydroxylase (DTH) is the rate limiting enzyme for DA biosynthesis. Viable brain DA-deficient flies were previously generated using tissue-selective GAL4-UAS binary expression rescue of a DTH null mutation and these flies show specific behavioral impairments. To circumvent the limitations of rescue via binary expression, here we achieve rescue utilizing genomically integrated mutant DTH. As expected, our DA-deficient flies have no detectable DTH or DA in the brain, and show reduced locomotor activity. This deficit can be rescued by l-DOPA/carbidopa feeding, similar to human Parkinson's disease treatment. Genetic rescue via GAL4/UAS-DTH was also successful, although this required the generation of a new UAS-DTH1 transgene devoid of most untranslated regions, as existing UAS-DTH transgenes express in the brain without a Gal4 driver via endogenous regulatory elements. A surprising finding of our newly constructed UAS-DTH1m is that it expresses DTH at an undetectable level when regulated by dopaminergic GAL4 drivers even when fully rescuing DA, indicating that DTH immunostaining is not necessarily a valid marker for DA expression. This finding necessitated optimizing DA immunohistochemistry, showing details of DA innervation to the mushroom body and the central complex. When DA rescue is limited to specific DA neurons, DA does not diffuse beyond the DTH-expressing terminals, such that DA signaling can be limited to very specific brain regions.


Assuntos
Encéfalo/metabolismo , Dopamina/deficiência , Drosophila/metabolismo , Animais , Modelos Animais de Doenças , Dopamina/genética , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Drosophila/genética , Levodopa/metabolismo , Masculino , Neurotransmissores/metabolismo , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo
8.
Endocr Regul ; 49(2): 91-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25960010

RESUMO

OBJECTIVE: The aim of the present study was to examine the association between subjects with self-awareness of fast eating and diagnostic components of metabolic syndrome in Japanese middle-aged male and female. PATIENTS AND METHODS: Subjects consisted of 3208 males (average age 50.6 years) and 2055 females (average age 50.0 years). Associations between subjects with self-awareness of fast eating and multiple components of metabolic syndrome (waist circumference, body mass index [BMI], blood pressure, and related blood sample tests) were evaluated. RESULTS: Significantly more males (57.7%) acknowledged themselves as "fast eater" than females (46.5%). Self-reported fast eaters showed significantly elevated body weight, BMI, and waist circumference in both genders. However, only male self-reported fast eaters showed high levels of blood pressure, fasting blood glucose, uric acid, and low-density lipoprotein (LDL)-cholesterol. CONCLUSION: Fast eating is associated with diagnostic components of metabolic syndrome. The effect of acknowledging themselves as fast eater presents a higher impact on males than on females in the middle-aged Japanese population. The present study indicates that finding subjects with self-awareness of fast eating may lead to the prevention of developing metabolic syndrome.


Assuntos
Conscientização , Comportamento Alimentar/fisiologia , Síndrome Metabólica/epidemiologia , Autoimagem , Adulto , Idoso , Comportamento Alimentar/psicologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais
9.
Insect Mol Biol ; 22(5): 523-31, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23803169

RESUMO

The glutathione S-transferase (GST) superfamily is involved in the detoxification of various xenobiotics. A silkworm GST, belonging to a previously reported Epsilon-class GST family, was identified, named bmGSTE, cloned, and produced in Escherichia coli. Investigation of this enzyme's properties showed that it was able to catalyse glutathione (GSH) with 1-chloro-2,4-dinitrobenzene and ethacrynic acid, and also that it possessed GSH-dependent peroxidase activity. The enzyme's highly conserved amino acid residues, including Ser11, His53, Val55, Ser68 and Arg112, were of interest regarding their possible involvement in its catalytic activity. These residues were replaced with alanine by site-directed mutagenesis and subsequent kinetic analysis of bmGSTE mutants indicated that His53, Val55, and Ser68 were important for enzyme function.


Assuntos
Bombyx/enzimologia , Glutationa Transferase/classificação , Glutationa Transferase/metabolismo , Proteínas de Insetos/classificação , Proteínas de Insetos/metabolismo , Sequência de Aminoácidos , Animais , Domínio Catalítico/genética , Domínio Catalítico/fisiologia , Glutationa Transferase/genética , Histidina/genética , Proteínas de Insetos/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Serina/genética , Valina/genética
10.
Diabet Med ; 29(1): 80-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22082489

RESUMO

AIM: Orthostatic hypotension is a hallmark of diabetic autonomic neuropathy and is associated with increased mortality. The serum level of adiponectin is elevated in patients with heart failure or renal failure. In the present study, we measured serum levels of total and high molecular weight adiponectin in patients with Type 2 diabetes and orthostatic hypotension. We also investigated the relationship between the presence of orthostatic hypotension and various clinical variables in patients with Type 2 diabetes. METHODS: We studied 105 patients with Type 2 diabetes. Orthostatic hypotension was defined as a decrease of 20 mmHg or more in systolic blood pressure and/or 10 mmHg in diastolic blood pressure when blood pressure was measured for 3 min while standing. The brachial-ankle pulse-wave velocity was also measured as an index of arterial stiffness. RESULTS: Orthostatic hypotension was found in 30 patients with diabetes (28.6%). The haematocrit and estimated glomerular filtration rate were significantly lower in patients with orthostatic hypotension than in those without it. Brachial-ankle pulse-wave velocity and serum total and high molecular weight adiponectin were significantly higher in patients with orthostatic hypotension than in those without. Furthermore, the high molecular weight/total adiponectin ratio was higher in patients with orthostatic hypotension than in those without and hypertension was more common in patients with orthostatic hypotension. Plasma prothrombin F1 + 2, a coagulation maker, was higher in patients with orthostatic hypotension than in those without, while there were no differences of fibrinolytic markers between the two groups. Multivariate analysis showed that HDL cholesterol, haematocrit, F1 + 2, brachial-ankle pulse-wave velocity and a decline of systolic blood pressure on standing were independent determinants of high molecular weight adiponectin. CONCLUSIONS: Patients with Type 2 diabetes and orthostatic hypotension had an elevated serum level of high molecular weight adiponectin, which was associated with the simultaneous presence of renal dysfunction, anaemia, arterial stiffness and hypercoagulability.


Assuntos
Adiponectina/sangue , Diabetes Mellitus Tipo 2/sangue , Neuropatias Diabéticas/sangue , Hipotensão Ortostática/sangue , Insuficiência Renal/sangue , Trombofilia/sangue , Rigidez Vascular , Índice Tornozelo-Braço , Pressão Sanguínea , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Neuropatias Diabéticas/complicações , Neuropatias Diabéticas/fisiopatologia , Feminino , Taxa de Filtração Glomerular , Humanos , Hipotensão Ortostática/complicações , Hipotensão Ortostática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Peso Molecular , Trombofilia/etiologia , Trombofilia/fisiopatologia
12.
Insect Mol Biol ; 20(3): 379-86, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21435060

RESUMO

The glutathione S-transferase (GST) superfamily is involved in detoxification of various xenobiotics. Using real-time PCR, mRNA encoding an omega-class GST of Bombyx mori (bmGSTO) was shown to be induced after exposure to various environmental stresses. A soluble form of recombinant protein (rbmGSTO) was functionally overexpressed in Escherichia coli cells and purified to homogeneity. Cys 38 and Pro 39 were found to be highly conserved in omega-class GSTs, and their roles were investigated by site-directed mutagenesis/kinetic analysis. Mutations of Cys 38 and Pro 39 residues affected the catalytic efficiency of enzymes, indicating that the presence of Cys 38 and Pro 39 residues is important for bmGSTO activity. Thus, bmGSTO could contribute to increasing the environmental stress resistance of lepidopteran insects.


Assuntos
Bombyx/fisiologia , Glutationa Transferase/metabolismo , Estresse Oxidativo , Sequência de Aminoácidos , Animais , Sequência de Bases , Bombyx/enzimologia , Bombyx/genética , Cisteína/genética , Escherichia coli/genética , Corpo Adiposo/enzimologia , Glutationa Transferase/genética , Peróxido de Hidrogênio/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Prolina/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Xenobióticos/metabolismo
13.
Phys Rev Lett ; 107(27): 271102, 2011 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-22243300

RESUMO

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2-20×10(-50) strain(2) Hz(-1) and 5-35×10(-49) strain(2) Hz(-1) sr(-1) for pointlike and extended sources, respectively. The latter result is the first of its kind. We also set 90% C.L. limits on the narrow-band root-mean-square GW strain from interesting targets including Sco X-1, SN 1987A and the Galactic center as low as ≈7×10(-25) in the most sensitive frequency range near 160 Hz.

14.
Protein Eng Des Sel ; 23(5): 385-92, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20159773

RESUMO

Fc engineering to increase the binding affinity of IgG antibodies to FcRn has been reported to reduce the elimination of IgG antibodies. Herein, we present a novel non-FcRn-dependent approach to reduce the elimination of IgG antibodies. Pharmacokinetic studies conducted in normal mice of various humanized IgG4 antibodies, which had identical constant regions but different variable region sequences, revealed that an antibody with a lower isoelectric point (pI) has a longer half-life. These antibodies exhibited comparable binding affinity to FcRn, and with the antibodies with lower pIs, a longer half-life was also observed in beta2-microglobulin knockout mice, suggesting that differences in the pharmacokinetics were due to a non-FcRn-dependent mechanism. On the basis of our findings, we attempted to engineer the pharmacokinetic properties of a humanized anti-IL6 receptor IgG1 antibody. Selected substitutions in the variable region, without substitution in the Fc region, lowered the pI but did not reduce the biological activity and showed a significant reduction in the clearance of the antibody in cynomolgus monkey. These results suggest that lowering the pI by engineering the variable region could reduce the elimination of IgG antibodies and could provide an alternative to Fc engineering of IgG antibodies.


Assuntos
Engenharia Genética/métodos , Imunoglobulina G/genética , Região Variável de Imunoglobulina/genética , Engenharia de Proteínas/métodos , Animais , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/farmacocinética , Células CHO , Cricetinae , Cricetulus , Meia-Vida , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imunoglobulina G/metabolismo , Ponto Isoelétrico , Camundongos , Receptores Fc/metabolismo
15.
Xenobiotica ; 39(11): 803-10, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19845431

RESUMO

It is important to predict CYP3A enzyme induction in the drug-discovery process to avoid adverse effects in clinical. In the present study, we constructed a method to correct the variability of in vitro CYP3A induction assays and thereby a method for the prediction of CYP3A induction in the clinical setting. Induction assays were performed in vitro using HepaRG cells and seven typical inducers. An index value was determined for enzyme induction, termed the relative factor (RF), from the ratio of the concentration of the inducers to the reference standards. Using RF as an index, variation among the assays was reduced. A good relationship was obtained between the ratio of the free plasma concentration at steady-state (C(ss,u)) to RF (expressed as C(ss,u)/RF) and the in vivo induction response. Using rifampicin as a reference standard, compounds with a C(ss,u)/RF value greater than 7.31 nmol l(-1) may induce CYP3A in vivo in humans.


Assuntos
Citocromo P-450 CYP3A/biossíntese , Hepatócitos/efeitos dos fármacos , Anticonvulsivantes/farmacologia , Bioensaio , Carbamazepina/farmacologia , Linhagem Celular , Indução Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Hepatócitos/enzimologia , Humanos , Fenobarbital/farmacologia , Rifampina/farmacologia
16.
Nature ; 460(7258): 990-4, 2009 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-19693079

RESUMO

A stochastic background of gravitational waves is expected to arise from a superposition of a large number of unresolved gravitational-wave sources of astrophysical and cosmological origin. It should carry unique signatures from the earliest epochs in the evolution of the Universe, inaccessible to standard astrophysical observations. Direct measurements of the amplitude of this background are therefore of fundamental importance for understanding the evolution of the Universe when it was younger than one minute. Here we report limits on the amplitude of the stochastic gravitational-wave background using the data from a two-year science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). Our result constrains the energy density of the stochastic gravitational-wave background normalized by the critical energy density of the Universe, in the frequency band around 100 Hz, to be <6.9 x 10(-6) at 95% confidence. The data rule out models of early Universe evolution with relatively large equation-of-state parameter, as well as cosmic (super)string models with relatively small string tension that are favoured in some string theory models. This search for the stochastic background improves on the indirect limits from Big Bang nucleosynthesis and cosmic microwave background at 100 Hz.

17.
Phys Rev Lett ; 102(11): 111102, 2009 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-19392186

RESUMO

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.

18.
Diabet Med ; 26(1): 83-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19125766

RESUMO

AIMS: To investigate the relationship between the novel post-occlusive forearm skin reactive hyperaemia (PORH) index and macro- and microangiopathy by comparing it with traditional indices and a morphological analysis of skin blood flow after ischaemia. METHODS: We studied 20 control subjects and 104 patients with Type 2 diabetes. Cutaneous blood flow (flux) in response to 5-min arterial occlusion in the forearm was measured using laser Doppler flowmetry. We defined the PORH index as the ratio of the area under the curve (AUC) 1 min after the release of the cuff relative to the AUC of a 1-min period before cuff inflation. The flux in response to arterial occlusion was divided morphologically into three patterns. Brachial-ankle pulse wave velocity (baPWV) was measured. RESULTS: The PORH index was markedly lower in patients with diabetes than in control subjects. The PORH index correlated negatively with urinary albumin, peroneal motor nerve conduction velocity, and baPWV in the patients with diabetes. The PORH index, but not the morphological analysis, was an independent determinant of cardiovascular disease in patients with diabetes. CONCLUSIONS: The PORH index may be the most sensitive indicator of micro- and macrovascular disease of the various measures of PORH in patients with Type 2 diabetes.


Assuntos
Arteriopatias Oclusivas/fisiopatologia , Diabetes Mellitus Tipo 2/complicações , Hiperemia/fisiopatologia , Fluxometria por Laser-Doppler/métodos , Idoso , Arteriopatias Oclusivas/diagnóstico , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Antebraço/irrigação sanguínea , Humanos , Hiperemia/diagnóstico , Fluxometria por Laser-Doppler/normas , Masculino , Microcirculação/fisiologia , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Pele/irrigação sanguínea , Vasodilatação/fisiologia
19.
Phys Rev Lett ; 101(21): 211102, 2008 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-19113401

RESUMO

We present a LIGO search for short-duration gravitational waves (GWs) associated with soft gamma ray repeater (SGR) bursts. This is the first search sensitive to neutron star f modes, usually considered the most efficient GW emitting modes. We find no evidence of GWs associated with any SGR burst in a sample consisting of the 27 Dec. 2004 giant flare from SGR 1806-20 and 190 lesser events from SGR 1806-20 and SGR 1900+14. The unprecedented sensitivity of the detectors allows us to set the most stringent limits on transient GW amplitudes published to date. We find upper limit estimates on the model-dependent isotropic GW emission energies (at a nominal distance of 10 kpc) between 3x10;{45} and 9x10;{52} erg depending on waveform type, detector antenna factors and noise characteristics at the time of the burst. These upper limits are within the theoretically predicted range of some SGR models.

20.
Complement Ther Clin Pract ; 14(3): 195-203, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18640631

RESUMO

UNLABELLED: This study examined the immediate effects of wrapped warm footbaths (WW Footbath) on the autonomic, neuroimmunological and psychological activities in healthy middle-aged volunteers. Thirteen subjects were divided into a footbath group (n=7) and a control group (n=6). Immediate changes in autonomic activities were recorded with wavelet analysis of heart rate variability. Salivary secretory immunoglobulin A (sIgA) and serum cortisol levels were used as neuroimmunological parameters. Psychological conditions were measured using a Visual Analog Scale. Parasympathetic activity tended to increase and sympathetic activity decrease after footbaths. RESULTS: Changes in the relaxation indices, that is, sIgA and serum cortisol levels showed that both lying down and footbath resulted in a relaxed state. CONCLUSION: WW Footbaths can be an effective method of relaxation, since it induces both a significant increase in parasympathetic activity and significant decrease in sympathetic activity.


Assuntos
Banhos , Hidrocortisona/sangue , Imunoglobulina A Secretora/análise , Sistema Nervoso Parassimpático , Terapia de Relaxamento , Sistema Nervoso Simpático , Fatores Etários , Eletrocardiografia , , Frequência Cardíaca , Humanos , Projetos Piloto , Saliva/química , Fatores Sexuais
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