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1.
Cereb Cortex ; 24(8): 2169-77, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23529004

RESUMO

Oftentimes, we perceive our environment by integrating information across multiple senses. Recent studies suggest that such integration occurs at much earlier processing stages than once thought possible, including in thalamic nuclei and putatively unisensory cortical brain regions. Here, we used diffusion tensor imaging (DTI) and an audiovisual integration task to test the hypothesis that anatomical connections between sensory-related subcortical structures and sensory cortical areas govern multisensory processing in humans. Twenty-five subjects (mean age 22 years, 22 females) participated in the study. In line with our hypothesis, we show that estimated strength of white-matter connections between the first relay station in the auditory processing stream (the cochlear nucleus), the auditory thalamus, and primary auditory cortex predicted one's ability to combine auditory and visual information in a visual search task. This finding supports a growing body of work that indicates that subcortical sensory pathways do not only feed forward unisensory information to the cortex, and suggests that anatomical brain connectivity contributes to multisensory processing ability in humans.


Assuntos
Percepção Auditiva , Encéfalo/anatomia & histologia , Percepção Visual , Estimulação Acústica , Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Imagem de Tensor de Difusão , Eletroculografia , Movimentos Oculares/fisiologia , Feminino , Humanos , Masculino , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Testes Neuropsicológicos , Estimulação Luminosa , Percepção Visual/fisiologia , Substância Branca/anatomia & histologia , Substância Branca/fisiologia , Adulto Jovem
2.
Commun Agric Appl Biol Sci ; 80(3): 539-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27141749

RESUMO

Hydroponic systems used for growing potted ornamentals in greenhouses are commonly ebb-and-flow irrigation systems. The drainage water is usually recycled to save water and nutrients. To avoid the spread of pathogens in these closed irrigation systems, disinfection of the recycled water is standard practice. Growers can use slow sand filtration or UV-radiation techniques, but these methods are often either not sulted for specific problems or they require an excessively large investment. The objective of this study was to test less expensive but effective alternative disinfection systems. The efficacy of five disinfection systems against fungi and oomycetes was determined: Aqua-Hort (based on Cu-ions), Reciclean (performic acid), D1-OX Forte (CIO2), ECA (electrochemically activated water = anodic oxidation: hypochlorite and free radicals) and Newtec (also anodic oxidation). These five systems and a no-sterilization control were integrated in small closed ebb-and-flow circuits with nutrient solution reservoirs of 400 L each. Activity against Fusarium was excellent with ECA, good with Newtec and DI-OX Forte, moderate with high doses of Reciclean (250 ppm H2O2 and poor with the Aqua-Hort. There was no Pythium in the ECA and Newtec systems, while still so in the Aqua-Hort system, even at high doses (up to 7 ppm Cu++). Although the Reciclean (up to 100 ppm H2O2) and Aqua-Hort systems did not perform well against the pathogens, they did very well against algae; especially Reciclean was also useful against duckweed in water and liverwort on soil substrates. Concentrations of total Cl were elevated in water, substrate and plants after treatments with ECA and Newtec; other accumulations were Cu (Aqua-Hort), Na and SO4 (DI-OX Forte). However, only on a limited number of plant species these accumulations produced phytotoxic effects.


Assuntos
Desinfecção/métodos , Água Doce/química , Purificação da Água/métodos , Irrigação Agrícola , Água Doce/microbiologia , Água Doce/parasitologia , Fusarium/crescimento & desenvolvimento , Hidroponia/instrumentação , Pythium/crescimento & desenvolvimento , Reciclagem , Purificação da Água/instrumentação
3.
Phys Rev Lett ; 113(18): 187002, 2014 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-25396390

RESUMO

We have generated frequency combs spanning 0.5 to 20 GHz in superconducting λ/2 resonators at T=3 K. Thin films of niobium-titanium nitride enabled this development due to their low loss, high nonlinearity, low frequency dispersion, and high critical temperature. The combs nucleate as sidebands around multiples of the pump frequency. Selection rules for the allowed frequency emission are calculated using perturbation theory, and the measured spectrum is shown to agree with the theory. Sideband spacing is measured to be accurate to 1 part in 10(8). The sidebands coalesce into a continuous comb structure observed to cover at least several frequency octaves.

4.
Phys Rev Lett ; 113(5): 050402, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25126902

RESUMO

We present measurements of a topological property, the Chern number (C_{1}), of a closed manifold in the space of two-level system Hamiltonians, where the two-level system is formed from a superconducting qubit. We manipulate the parameters of the Hamiltonian of the superconducting qubit along paths in the manifold and extract C_{1} from the nonadiabatic response of the qubit. By adjusting the manifold such that a degeneracy in the Hamiltonian passes from inside to outside the manifold, we observe a topological transition C_{1}=1→0. Our measurement of C_{1} is quantized to within 2% on either side of the transition.

5.
Commun Agric Appl Biol Sci ; 79(2): 207-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26084099

RESUMO

If a grower uses predatory mites, and should use chemical compounds, he needs to be very careful in his choice of products. The selected products have to be efficient against the target pest and at the same time compatible with the present beneficial's. Useful tools for such product selection under greenhouse circumstances are side effects lists. These lists are freely available on the websites of producing companies of biological control agents. But not all products (e.g. newly developed ones) have been tested for side effects. Moreover the information already available in these tables is not based on field tests. For this reason, we have developed a protocol for quick screening of side effects of chemical plant protection products under field conditions. For these experiments we have chosen the predatory mite Amblyseius swirskii as test organism, because this is an often used phytoseiid mite, which is very sensitive to pesticides. Hibiscus rosa sinensis is the standard reference plant in our side effects trials because the chosen predatory mite has shown very good control of pests on this plant species. The experimental design consists of eight test objects in 4 replications. Test object 1 is a positive reference (water spray) and test object 2 a negative reference (deltamethrin spray, a product with long residual activity against beneficial organisms). The plot size is 0,68 m2 and each plot contains 32 Hibiscus plants. The greenhouse temperature is set at 20±2°C. The test strategy has the following sequence: introduction of an overdose of Amblyseius swirskii mites 14 days before spraying the pesticides > precount of predatory mites 4 days before application (4DBA) > spray application (A) for the 6 test products and for the 2 references > counting's after application (1, 2, 4, 8 en 12 weeks after application = 1 till 12WAA). The counting's of the number of predatory mites are performed on 20 Hibiscus leaves/plot under a binocular. Because of the absence of any food sources for the A. swirskii mites, it's necessary to re-introduce a high dose of predatory mites in the Hibiscus crop every 4 weeks, especially 2 weeks before the counting's 4, 8 and 12WAA; these introductions are carried out by hanging out 7 sachets with predatory mites (250 mites/sachet or 2500 mites/m2) on each test plot and after 10 days they are removed. In our first experiments the following commercial products have been tested: Pyrethro Pur (rapeseed oil + pyrethrins), Actara (thiamethoxam), Rizolex 500 SC (tolclofos-methyl), Topsin 500 SC (thiophanate-methyl), Floramite 240 SC (bifenazate), Cycocel 75 (chlorrmequat chloride), Vertimec (abamectin), Match (lufenuron), Nocturn (pyridalyl), Neemazal-T/S (azadirachtin), Tracer (spinosad), Envidor (spirodiclofen), Carex 10SC (pyridaben), Nissorun (hexythiazox) and Scelta (cyflumetofen). As expected the water treatment was safest for A. swirskii and deltamethrin killed most of the mites, even if they were re-introduced after 8 or 12 weeks. Also pyrethrins and spinosad showed very negative effects. Abamectin and bifenazate showed intermediate negative effects and should be used with caution. The other products were safe to use in combination with predatory mites. These screening tests will be repeated yearly with new and popular products of which the side effects in practice are currently uncertain.


Assuntos
Hibiscus/parasitologia , Ácaros/efeitos dos fármacos , Praguicidas/toxicidade , Doenças das Plantas/parasitologia , Animais , Hibiscus/crescimento & desenvolvimento , Ácaros/fisiologia , Controle de Pragas , Doenças das Plantas/prevenção & controle , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/parasitologia
6.
Osteoarthritis Cartilage ; 21(12): 1834-40, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24012622

RESUMO

BACKGROUND: A subset of patients with total hip arthroplasty (THA) or total knee arthroplasty (TKA) has suboptimal postoperative results in terms of Patient Reported Outcomes (PROs), and psychological factors could contribute to these suboptimal results. OBJECTIVES: To examine the prevalence of anxiety and depressive symptoms in patients undergoing primary THA or TKA preoperatively and postoperatively, and the relationship between preoperative anxiety and depressive symptoms on PROs of THA and TKA. DESIGN: In this prospective study patients were measured preoperatively, and 3 and 12 months postoperatively. Patients filled in the Hospital Anxiety and Depression Scale, Knee injury and Osteoarthritis Outcome Score (KOOS) or Hip disability and Osteoarthritis Outcome Score (HOOS) and a satisfaction questionnaire. RESULTS: Data were obtained from 149 hip and 133 knee patients. The prevalence of anxiety symptoms decreased significantly from 27.9% to 10.8% 12 months postoperatively in hip patients, and from 20.3% to 14.8% in knee patients. Depressive symptoms decreased significantly from 33.6% to 12.1% 12 months postoperatively in hip patients, and from 22.7% to 11.7% in knee patients. In hip and knee patients, preoperative depressive symptoms predicted smaller changes in different HOOS or KOOS subscales and patients were less satisfied 12 months postoperatively. CONCLUSIONS: Preoperatively, the prevalence of anxiety and depressive symptoms was high. At 3 and 12 months postoperatively, the prevalence of anxiety and depressive symptoms was decreased in both hip and knee patients. However, patients with preoperative anxiety and depressive symptoms had worse PROs 3 and 12 months after THA and TKA and were less satisfied than patients without anxiety or depressive symptoms.


Assuntos
Ansiedade/psicologia , Artroplastia de Quadril/psicologia , Artroplastia do Joelho/psicologia , Depressão/psicologia , Osteoartrite do Quadril/psicologia , Osteoartrite do Joelho/psicologia , Idoso , Idoso de 80 Anos ou mais , Ansiedade/epidemiologia , Depressão/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/cirurgia , Osteoartrite do Joelho/cirurgia , Satisfação do Paciente , Prevalência , Estudos Prospectivos , Inquéritos e Questionários , Resultado do Tratamento
7.
Redox Biol ; 67: 102918, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37812879

RESUMO

We recently developed a novel keratin-derived protein (KDP) rich in cysteine, glycine, and arginine, with the potential to alter tissue redox status and insulin sensitivity. The KDP was tested in 35 human adults with type-2 diabetes mellitus (T2DM) in a 14-wk randomised controlled pilot trial comprising three 2×20 g supplemental protein/day arms: KDP-whey (KDPWHE), whey (WHEY), non-protein isocaloric control (CON), with standardised exercise. Outcomes were measured morning fasted and following insulin-stimulation (80 mU/m2/min hyperinsulinaemic-isoglycaemic clamp). With KDPWHE supplementation there was good and very-good evidence for moderate-sized increases in insulin-stimulated glucose clearance rate (GCR; 26%; 90% confidence limits, CL 2%, 49%) and skeletal-muscle microvascular blood flow (46%; 16%, 83%), respectively, and good evidence for increased insulin-stimulated sarcoplasmic GLUT4 translocation (18%; 0%, 39%) vs CON. In contrast, WHEY did not effect GCR (-2%; -25%, 21%) and attenuated HbA1c lowering (14%; 5%, 24%) vs CON. KDPWHE effects on basal glutathione in erythrocytes and skeletal muscle were unclear, but in muscle there was very-good evidence for large increases in oxidised peroxiredoxin isoform 2 (oxiPRX2) (19%; 2.2%, 35%) and good evidence for lower GPx1 concentrations (-40%; -4.3%, -63%) vs CON; insulin stimulation, however, attenuated the basal oxiPRX2 response (4%; -16%, 24%), and increased GPx1 (39%; -5%, 101%) and SOD1 (26%; -3%, 60%) protein expression. Effects of KDPWHE on oxiPRX3 and NRF2 content, phosphorylation of capillary eNOS and insulin-signalling proteins upstream of GLUT4 translocation AktSer437 and AS160Thr642 were inconclusive, but there was good evidence for increased IRSSer312 (41%; 3%, 95%), insulin-stimulated NFκB-DNA binding (46%; 3.4%, 105%), and basal PAK-1Thr423/2Thr402 phosphorylation (143%; 66%, 257%) vs WHEY. Our findings provide good evidence to suggest that dietary supplementation with a novel edible keratin protein in humans with T2DM may increase glucose clearance and modify skeletal-muscle tissue redox and insulin sensitivity within systems involving peroxiredoxins, antioxidant expression, and glucose uptake.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Adulto , Humanos , Glucose/metabolismo , Cisteína/metabolismo , Projetos Piloto , Insulina/metabolismo , Músculo Esquelético/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Isoformas de Proteínas/metabolismo , Suplementos Nutricionais , Oxirredução , Queratinas/metabolismo , Queratinas/farmacologia
8.
J Lipid Res ; 53(5): 979-983, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22375030

RESUMO

The extent of hypercholesterolemia varies considerably in patients with familial hypercholesterolemia (FH). We hypothesized that the variability of the FH phenotype might be partly explained by variation in proprotein convertase subtilisin kexin type 9 (PCSK9) activity. Individuals between 18 and 53 years of age who had been tested for a pathogenic LDLR or APOB mutation were eligible. Mutation carriers with a LDL-C level below the 75(th) percentile (called "FH low") were selected, as well as those with LDL-C above the 90(th) percentile (called "FH high"). Relatives who tested negative for the mutation were the "controls." PCSK9 plasma levels were assessed in 267 individuals who did not receive cholesterol-lowering treatment at the time of the study. Mean PCSK9 plasma levels (95% CI) were lower in the FH-low group compared with the FH-high group [152 (137-167) ng/ml vs. 186 (165-207) ng/ml, P = 0.010] and the control group [177 (164-190) ng/ml, P = 0.013]. Mean PCSK9 levels did not statistically differ between the FH-high and control groups (P = 0.50). Plasma PCSK9 levels are positively associated with LDL-C levels in FH patients and might contribute to the phenotypic severity in this disorder. Therefore, the results of pharmaceutical inhibition of PCSK9 in FH patients are eagerly awaited.


Assuntos
Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/genética , Fenótipo , Pró-Proteína Convertases/sangue , Serina Endopeptidases/sangue , Adolescente , Adulto , Espessura Intima-Media Carotídea , LDL-Colesterol/sangue , Análise Mutacional de DNA , Feminino , Testes Genéticos , Humanos , Hiperlipoproteinemia Tipo II/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pró-Proteína Convertase 9 , Adulto Jovem
9.
Phys Rev Appl ; 17(4)2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37965129

RESUMO

Most microwave readout architectures in quantum computing or sensing rely on a semiconductor amplifier at 4 K, typically a high-electron mobility transistor (HEMT). Despite its remarkable noise performance, a conventional HEMT dissipates several milliwatts of power, posing a practical challenge to scale up the number of qubits or sensors addressed in these architectures. As an alternative, we present an amplification chain consisting of a kinetic inductance traveling-wave parametric amplifier (KITWPA) placed at 4 K, followed by a HEMT placed at 70 K, and demonstrate a chain-added noise TΣ=6.3±0.5K between 3.5 and 5.5 GHz. While, in principle, any parametric amplifier can be quantum limited even at 4 K, in practice we find the performance of the KITWPA to be limited by the temperature of its inputs and by an excess of noise Tex=1.9K. The dissipation of the rf pump of the KITWPA constitutes the main power load at 4 K and is about 1% that of a HEMT. These combined noise and power dissipation values pave the way for the use of the KITWPA as a replacement for semiconductor amplifiers.

10.
Osteoarthritis Cartilage ; 19(9): 1102-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21723401

RESUMO

OBJECTIVE: An earlier study showed that 6 months after total hip arthroplasty (THA) patients' overall daily activity level had not increased, despite significant improvement in their perceived physical functioning. This discrepancy might be because postoperative recovery is not expressed by a more overall active lifestyle, but by the fact that patients could perform the individual activities of daily living (ADL) faster and/or for a longer period of time. The aim of this study was to assess whether patients perform ADL faster and/or for a longer period of time 6 months post-THA compared to baseline. Also examined was whether patients perform activities on the level of healthy matched controls. METHOD: Thirty patients were measured at home with an accelerometry-based Activity Monitor, pre-operatively and 6 months post-THA. Patients were matched with healthy controls on gender and age (±2 years). RESULTS: Compared with baseline, 6 months post-THA the stride frequency and body motility during walking of patients had increased [56.1 (54.3, 57.8)strides/min vs 52.1 (50.3, 54.1)strides/min; P-value<0.0001, and 0.265 (0.245, 0.286)g vs 0.219 (0.197, 0.240)g; P-value<0.0001], and they rose faster from a chair [2.6 (2.5, 2.8)s vs 3.0 (2.8, 3.2)s; P-value<0.0001]. Compared with controls, preoperative all patients had lower values for these parameters. Six months post-THA the stride frequency and body motility during walking were similar to that of controls, but patients rose slower from a chair than controls. CONCLUSION: Six months post-THA patients walked faster and rose from a chair faster compared to baseline. Patients walked as fast as healthy controls but took longer rising from a chair.


Assuntos
Atividades Cotidianas , Artroplastia de Quadril/reabilitação , Osteoartrite do Quadril/reabilitação , Recuperação de Função Fisiológica/fisiologia , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial , Atividade Motora/fisiologia , Osteoartrite do Quadril/cirurgia , Período Pós-Operatório , Estudos Prospectivos , Resultado do Tratamento , Caminhada/fisiologia
11.
Neth Heart J ; 19(4): 175-182, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21475731

RESUMO

BACKGROUND: In the Netherlands, a screening programme was set up in 1994 in order to identify all patients with familial hypercholesterolaemia (FH). After 15 years of screening, we evaluated the geographical distribution, possible founder effects and clinical phenotype of the 12 most prevalent FH gene mutations. METHODS: Patients who carried one of the 12 most prevalent mutations, index cases and those identified between 1994 and 2009 through the screening programme and whose postal code was known were included in the study. Low-density lipoprotein cholesterol (LDL-C) levels at the time of screening were retrieved. The prevalence of identified FH patients in each postal code area was calculated and visualised in different maps. RESULTS: A total of 10,889 patients were included in the study. Mean untreated LDL-C levels ranged from 4.4 to 6.4 mmol/l. For almost all mutations, a region of high prevalence could be observed. In total, 51 homozygous patients were identified in the Netherlands, of which 13 true homozygous for one of the 12 most prevalent mutations. The majority of them were living in high-prevalence areas for that specific mutation. CONCLUSIONS: Phenotypes with regard to LDL-C levels varied between the 12 most prevalent FH mutations. For most of these mutations, a founder effect was observed. Our observations can have implications with regard to the efficiency of molecular screening and physician's perception of FH and to the understanding of the prevalence and distribution of homozygous patients in the Netherlands.

12.
J Infect ; 83(6): 709-737, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34715239

RESUMO

Molecular diagnosis; Viral infection; Chemokines; Disease prognosis; CXCL10; CXCL11; CCL3; CCL4; CCL5; Random forest.


Assuntos
Quimiocina CXCL10 , Adulto , Criança , Humanos
13.
J Lipid Res ; 51(4): 755-62, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19828909

RESUMO

Subjects with increased cholesterol absorption might benefit more from statin therapy combined with a cholesterol absorption inhibitor. We assessed whether baseline cholesterol absorption markers were associated with response to ezetimibe/simvastatin therapy, in terms of LDL-cholesterol (LDL-C) lowering and cholesterol absorption inhibition, in patients with familial hypercholesterolemia (FH). In a posthoc analysis of the two-year ENHANCE trial, we assessed baseline cholesterol-adjusted campesterol (campesterol/TC) and sitosterol/TC ratios in 591 FH patients. Associations with LDL-C changes and changes in cholesterol absorption markers were evaluated by multiple regression analysis. No association was observed between baseline markers of cholesterol absorption and the extent of LDL-C response to ezetimibe/simvastatin therapy (beta = 0.020, P = 0.587 for campesterol/TC and beta<0.001, P = 0.992 for sitosterol/TC). Ezetimibe/simvastatin treatment reduced campesterol levels by 68% and sitosterol levels by 62%; reductions were most pronounced in subjects with the highest cholesterol absorption markers at baseline, the so-called high absorbers (P < 0.001). Baseline cholesterol absorption status does not determine LDL-C lowering response to ezetimibe/simvastatin therapy in FH, despite more pronounced cholesterol absorption inhibition in high absorbers. Hence, these data do not support the use of baseline absorption markers as a tool to determine optimal cholesterol lowering strategy in FH patients. However, due to the exploratory nature of any posthoc analysis, these results warrant further prospective evaluation in different populations.


Assuntos
Anticolesterolemiantes/uso terapêutico , Azetidinas/uso terapêutico , Colesterol/sangue , Colesterol/metabolismo , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Absorção Intestinal/efeitos dos fármacos , Sinvastatina/uso terapêutico , Adulto , Idoso , Anticolesterolemiantes/classificação , Biomarcadores/sangue , Colesterol/análogos & derivados , LDL-Colesterol/sangue , Método Duplo-Cego , Quimioterapia Combinada , Ezetimiba , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Pessoa de Meia-Idade , Fitosteróis/sangue , Sitosteroides/sangue , Estatística como Assunto
14.
J Exp Med ; 168(3): 1169-74, 1988 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-3049904

RESUMO

We infused microgram quantities of active or inactive PMN elastase and cathepsin G into the renal arteries of rats. Both active and inactive elastase localized to the glomerular capillary wall equally, and in amounts that could be achieved physiologically in GN. However, elastase-perfused rats developed marked proteinuria (196 +/- 32 mg/24 h) compared with control rats receiving inactive elastase (19 +/- 2 mg/24 h, p less than 0.005). Similar results were seen with active and inactive cathepsin G. Neither elastase nor cathepsin G infusion was associated with histologic evidence of glomerular injury. We conclude that the PMN neutral serine proteinases elastase and cathepsin G can mediate marked changes in glomerular permeability in vivo due to their proteolytic activity, and thus, may contribute to the proteinuria observed in PMN-dependent models of GN.


Assuntos
Catepsinas/fisiologia , Nefropatias/enzimologia , Neutrófilos/enzimologia , Elastase Pancreática/fisiologia , Animais , Catepsina G , Imunofluorescência , Nefropatias/patologia , Glomérulos Renais/patologia , Proteinúria/etiologia , Ratos , Serina Endopeptidases
15.
Rev Sci Instrum ; 91(9): 091101, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33003823

RESUMO

The performance of superconducting circuits for quantum computing is limited by materials losses. In particular, coherence times are typically bounded by two-level system (TLS) losses at single photon powers and millikelvin temperatures. The identification of low loss fabrication techniques, materials, and thin film dielectrics is critical to achieving scalable architectures for superconducting quantum computing. Superconducting microwave resonators provide a convenient qubit proxy for assessing performance and studying TLS loss and other mechanisms relevant to superconducting circuits such as non-equilibrium quasiparticles and magnetic flux vortices. In this review article, we provide an overview of considerations for designing accurate resonator experiments to characterize loss, including applicable types of losses, cryogenic setup, device design, and methods for extracting material and interface losses, summarizing techniques that have been evolving for over two decades. Results from measurements of a wide variety of materials and processes are also summarized. Finally, we present recommendations for the reporting of loss data from superconducting microwave resonators to facilitate materials comparisons across the field.

16.
J Low Temp Phys ; 199(3-4)2020.
Artigo em Inglês | MEDLINE | ID: mdl-33487736

RESUMO

We describe the design and measurement of feedhorn-coupled, transition-edge sensor (TES) polarimeters with two passbands centered at 220 GHz and 280 GHz, intended for observations of the cosmic microwave background. Each pixel couples polarized light in two linear polarizations by use of a planar orthomode transducer and senses power via four TES bolometers, one for each band in each linear polarization. Previous designs of this detector architecture incorporated passbands from 27 to 220 GHz; we now demonstrate this technology at frequencies up to 315 GHz. Observational passbands are defined with an on-chip diplexer, and Fourier-transform-spectrometer measurements are in excellent agreement with simulations. We find coupling from feedhorn to TES bolometer using a cryogenic, temperature-controlled thermal source. We determine the optical efficiency of our device is η = 77% ± 6% (75% ± 5%) for 220 (280) GHz, relative to the designed passband shapes. Lastly, we compare two power-termination schemes commonly used in wide-bandwidth millimeter-wave polarimeters and find equal performance in terms of optical efficiency and passband shape.

17.
Br J Sports Med ; 43(5): 347-51, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18603576

RESUMO

OBJECTIVE: To compare long term outcome of highly active patients with anterior cruciate ligament ruptures treated operatively versus non-operatively. DESIGN: We reviewed high level athletes with an anterior cruciate ligament rupture on either MRI or arthroscopic evaluation more than 10 years previously, who were treated conservatively. They were pair-matched with patients who had had an anterior cruciate ligament reconstruction with bone-patella-tendon-bone, with respect to age, gender and Tegner activity score before injury. PARTICIPANTS: In total 50 patients were pair-matched. RESULTS: We found no statistical difference between the patients treated conservatively or operatively with respect to osteoarthritis or meniscal lesions of the knee, as well as activity level, objective and subjective functional outcome. The patients who were treated operatively had a significantly better stability of the knee at examination. CONCLUSION: We conclude that the instability repair using a bone-patella-tendon-bone anterior cruciate ligament reconstruction is a good knee stabilising operation. Both treatment options however show similar patient outcome at 10 year follow up.


Assuntos
Lesões do Ligamento Cruzado Anterior , Traumatismos em Atletas/terapia , Enxerto Osso-Tendão Patelar-Osso , Adulto , Ligamento Cruzado Anterior/cirurgia , Traumatismos em Atletas/cirurgia , Exercício Físico/fisiologia , Terapia por Exercício/métodos , Feminino , Seguimentos , Humanos , Masculino , Análise por Pareamento , Meniscos Tibiais/cirurgia , Osteoartrite do Joelho/etiologia , Modalidades de Fisioterapia , Ruptura/cirurgia , Ruptura/terapia , Lesões do Menisco Tibial , Resultado do Tratamento
18.
Arterioscler Thromb Vasc Biol ; 27(8): 1803-10, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17569881

RESUMO

OBJECTIVE: Functional and morphological changes of the arterial wall already present in young children with heterozygous familial hypercholesterolemia (HeFH) suggest that treatment should be initiated early in life to prevent premature atherosclerotic cardiovascular disease. The purpose of this study was to assess the efficacy and particularly safety of statin therapy in children with HeFH. METHODS AND RESULTS: We performed a meta-analysis of randomized, double-blind, placebo-controlled trials evaluating statin therapy in children aged 8 to 18 years with HeFH. Six studies (n=798 children) with 12 to 104 weeks of treatment were included. Total cholesterol, LDL cholesterol, and apolipoprotein B were significantly reduced, whereas HDL cholesterol and apolipoprotein A1 were significantly increased by statin therapy. No statistically significant differences were found between statin- and placebo-treated children with respect to the occurrence of adverse events (RR 0.99; 95% CI: 0.79 to 1.25), sexual development (RR of advancing > or = 1 stage in Tanner classification 0.96; 95% CI: 0.79 to 1.17), muscle toxicity (RR of CK > or = 10 times the upper limit of normal [ULN] 1.38; 95% CI: 0.18 to 10.82), or liver toxicity (RR of > or = 3 times the ULN for ASAT 0.98; 95% CI: 0.23 to 4.26 and for ALAT 2.03; 95% CI: 0.24 to 16.95). We found a minimal difference in growth in favor of the statin group (0.33 cm; 95% CI: 0.03 cm to 0.63 cm). CONCLUSION: In addition to the fact that statin treatment is efficacious, our results support the notion that statin treatment in children with HeFH is safe. Thus, even though further studies are required to assess lifelong safety, statin treatment should be considered for all children aged 8 to 18 with HeFH.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Adolescente , Fatores Etários , Criança , HDL-Colesterol/sangue , HDL-Colesterol/efeitos dos fármacos , LDL-Colesterol/sangue , LDL-Colesterol/efeitos dos fármacos , Intervalos de Confiança , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Seguimentos , Humanos , Masculino , Probabilidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Resultado do Tratamento
19.
Water Sci Technol ; 57(8): 1277-86, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18469402

RESUMO

In the Netherlands, many of the fresh groundwater resources are vulnerable to pollution. Owing to high population densities and intensive farming practices, pesticide residues are found in groundwater at many places. Hence a number of drinking water abstraction wells contain pesticides residues, causing considerable costs for purification. The Water Framework Directive (WFD) requires countries to assess the chemical status of groundwater bodies and set up monitoring plans for groundwater quality, including pesticides. 771 groundwater samples were taken from monitoring wells in 2006 and analysed for a broad list of pesticides in order to fulfil these requirements. Pesticide were detected in 27% of samples, while in 11% the WFD limit of 0.1 microg/l was exceeded. In this paper, these and earlier measurements are evaluated further, considering also measurements in drinking water wells, information about the origin of measured pesticides and calculated trends in use and emissions. The measurements in the monitoring wells showed that where pesticides are used, 15-55% (minimal and maximal estimation) of the wells in shallow groundwater (1 to 20 m below soil surface) contain pesticides residues at concentrations above 0.1 microg/l. When the metabolites BAM and AMPA are excluded (as not relevant in human toxicological terms), the estimation range is 7-37%. These patterns observed in shallow groundwater are reflected by the occurrence of pesticides in vulnerable abstraction wells that are used for the production of drinking water. The WFD requires the determination of both status and trends. The design of current monitoring network is evaluated from this perspective. Several recommendations are made for more adequate and efficient monitoring.


Assuntos
Praguicidas/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/análise , Abastecimento de Água/análise , Monitoramento Ambiental , Geografia , Guias como Assunto , Países Baixos , Resíduos de Praguicidas/análise , Valores de Referência
20.
J Low Temp Phys ; 193(3-4)2018.
Artigo em Inglês | MEDLINE | ID: mdl-34815585

RESUMO

Microwave Kinetic Inductance Detectors (MKIDs) provide a compelling path forward to the large-format polarimeter, imaging, and spectrometer arrays needed for next-generation experiments in millimeter-wave cosmology and astronomy. We describe the development of feedhorn-coupled MKID detectors for the TolTEC millimeter-wave imaging polarimeter being constructed for the 50-meter Large Millimeter Telescope (LMT). Observations with TolTEC are planned to begin in early 2019. TolTEC will comprise ∼7,000 polarization sensitive MKIDs and will represent the first MKID arrays fabricated and deployed on monolithic 150 mm diameter silicon wafers - a critical step towards future large-scale experiments with over 105 detectors. TolTEC will operate in observational bands at 1.1, 1.4, and 2.0 mm and will use dichroic filters to define a physically independent focal plane for each passband, thus allowing the polarimeters to use simple, direct-absorption inductive structures that are impedance matched to incident radiation. This work is part of a larger program at NIST-Boulder to develop MKID-based detector technologies for use over a wide range of photon energies spanning millimeter-waves to X-rays. We present the detailed pixel layout and describe the methods, tools, and flexible design parameters that allow this solution to be optimized for use anywhere in the millimeter and sub-millimeter bands. We also present measurements of prototype devices operating in the 1.1 mm band and compare the observed optical performance to that predicted from models and simulations.

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