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1.
Sci Rep ; 12(1): 21657, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36522382

RESUMO

Two-dimensional (2D) triangular lattice antiferromagnets (2D-TLA) often manifest intriguing physical and technological properties, due to the strong interplay between lattice geometry and electronic properties. The recently synthesized 2-dimensional transition metal dichalcogenide LiCrTe[Formula: see text], being a 2D-TLA, enriched the range of materials which can present such properties. In this work, muon spin rotation ([Formula: see text]SR) and neutron powder diffraction (NPD) have been utilized to reveal the true magnetic nature and ground state of LiCrTe[Formula: see text]. From high-resolution NPD the magnetic spin order at base-temperature is not, as previously suggested, helical, but rather collinear antiferromagnetic (AFM) with ferromagnetic (FM) spin coupling within the ab-plane and AFM coupling along the c-axis. The value if the ordered magnetic Cr moment is established as [Formula: see text]. From detailed [Formula: see text]SR measurements we observe an AFM ordering temperature [Formula: see text] K. This value is remarkably higher than the one previously reported by magnetic bulk measurements. From [Formula: see text]SR we are able to extract the magnetic order parameter, whose critical exponent allows us to categorize LiCrTe[Formula: see text] in the 3D Heisenberg AFM universality class. Finally, by combining our magnetic studies with high-resolution synchrotron X-ray diffraction (XRD), we find a clear coupling between the nuclear and magnetic spin lattices. This suggests the possibility for a strong magnon-phonon coupling, similar to what has been previously observed in the closely related compound LiCrO[Formula: see text].

2.
Mol Genet Metab ; 131(1-2): 23-37, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33093005

RESUMO

The nutrition management guideline for very-long chain acyl-CoA dehydrogenase deficiency (VLCAD) is the fourth in a series of web-based guidelines focusing on the diet treatment for inherited metabolic disorders and follows previous publication of guidelines for maple syrup urine disease (2014), phenylketonuria (2016) and propionic acidemia (2019). The purpose of this guideline is to establish harmonization in the treatment and monitoring of individuals with VLCAD of all ages in order to improve clinical outcomes. Six research questions were identified to support guideline development on: nutrition recommendations for the healthy individual, illness management, supplementation, monitoring, physical activity and management during pregnancy. This report describes the methodology used in its development including review, critical appraisal and abstraction of peer-reviewed studies and unpublished practice literature; expert input through two Delphi surveys and a nominal group process; and external review from metabolic physicians and dietitians. It includes the summary statements of the nutrition management recommendations for each research question, followed by a standardized rating based on the strength of the evidence. Online, open access of the full published guideline allows utilization by health care providers, researchers and collaborators who advise, advocate and care for individuals with VLCAD and their families and can be accessed from the Genetic Metabolic Dietitians International (https://GMDI.org) and Southeast Regional Genetics Network (https://southeastgenetics.org/ngp) websites.


Assuntos
Acil-CoA Desidrogenase de Cadeia Longa/genética , Síndrome Congênita de Insuficiência da Medula Óssea/dietoterapia , Erros Inatos do Metabolismo Lipídico/dietoterapia , Doenças Mitocondriais/dietoterapia , Doenças Musculares/dietoterapia , Política Nutricional , Acil-CoA Desidrogenase de Cadeia Longa/metabolismo , Síndrome Congênita de Insuficiência da Medula Óssea/genética , Síndrome Congênita de Insuficiência da Medula Óssea/metabolismo , Síndrome Congênita de Insuficiência da Medula Óssea/patologia , Feminino , Guias como Assunto , Humanos , Erros Inatos do Metabolismo Lipídico/genética , Erros Inatos do Metabolismo Lipídico/metabolismo , Erros Inatos do Metabolismo Lipídico/patologia , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/patologia , Doenças Musculares/genética , Doenças Musculares/metabolismo , Doenças Musculares/patologia , Terapia Nutricional , Gravidez
3.
Sci Adv ; 5(11): eaav8465, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31819897

RESUMO

We report on muon spin rotation experiments probing the magnetic penetration depth λ(T) in the layered superconductors in 2H-NbSe2 and 4H-NbSe2. The current results, along with our earlier findings on 1T'-MoTe2 (Guguchia et al.), demonstrate that the superfluid density scales linearly with T c in the three transition metal dichalcogenide superconductors. Upon increasing pressure, we observe a substantial increase of the superfluid density in 2H-NbSe2, which we find to correlate with T c. The correlation deviates from the abovementioned linear trend. A similar deviation from the Uemura line was also observed in previous pressure studies of optimally doped cuprates. This correlation between the superfluid density and T c is considered a hallmark feature of unconventional superconductivity. Here, we show that this correlation is an intrinsic property of the superconductivity in transition metal dichalcogenides, whereas the ratio T c/T F is approximately a factor of 20 lower than the ratio observed in hole-doped cuprates. We, furthermore, find that the values of the superconducting gaps are insensitive to the suppression of the charge density wave state.

5.
Sci Adv ; 4(12): eaat3672, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30588488

RESUMO

Transition metal dichalcogenides (TMDs) are interesting for understanding the fundamental physics of two-dimensional (2D) materials as well as for applications to many emerging technologies, including spin electronics. Here, we report the discovery of long-range magnetic order below T M = 40 and 100 K in bulk semiconducting TMDs 2H-MoTe2 and 2H-MoSe2, respectively, by means of muon spin rotation (µSR), scanning tunneling microscopy (STM), and density functional theory (DFT) calculations. The µSR measurements show the presence of large and homogeneous internal magnetic fields at low temperatures in both compounds indicative of long-range magnetic order. DFT calculations show that this magnetism is promoted by the presence of defects in the crystal. The STM measurements show that the vast majority of defects in these materials are metal vacancies and chalcogen-metal antisites, which are randomly distributed in the lattice at the subpercent level. DFT indicates that the antisite defects are magnetic with a magnetic moment in the range of 0.9 to 2.8 µB. Further, we find that the magnetic order stabilized in 2H-MoTe2 and 2H-MoSe2 is highly sensitive to hydrostatic pressure. These observations establish 2H-MoTe2 and 2H-MoSe2 as a new class of magnetic semiconductors and open a path to studying the interplay of 2D physics and magnetism in these interesting semiconductors.

6.
Phys Rev Lett ; 120(15): 156403, 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29756873

RESUMO

The success of black phosphorus in fast electronic and photonic devices is hindered by its rapid degradation in the presence of oxygen. Orthorhombic tin selenide is a representative of group IV-VI binary compounds that are robust and isoelectronic and share the same structure with black phosphorus. We measure the band structure of SnSe and find highly anisotropic valence bands that form several valleys having fast dispersion within the layers and negligible dispersion across. This is exactly the band structure desired for efficient thermoelectric generation where SnSe has shown great promise.

7.
Nat Commun ; 9(1): 201, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29321471

RESUMO

The original version of this article omitted the following from the Acknowledgements: "CAM and AL were supported by the NSF MRSEC program through Columbia in the Center for Precision Assembly of Superstratic and Superatomic Solids (DMR-1420634). Additionally, this research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under 'Contract No. DE-AC02-05CH11231'." This has now been corrected in both the PDF and HTML versions of the article.

8.
Nat Commun ; 8(1): 1082, 2017 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-29057874

RESUMO

In its orthorhombic T d polymorph, MoTe2 is a type-II Weyl semimetal, where the Weyl fermions emerge at the boundary between electron and hole pockets. Non-saturating magnetoresistance and superconductivity were also observed in T d-MoTe2. Understanding the superconductivity in T d-MoTe2, which was proposed to be topologically non-trivial, is of eminent interest. Here, we report high-pressure muon-spin rotation experiments probing the temperature-dependent magnetic penetration depth in T d-MoTe2. A substantial increase of the superfluid density and a linear scaling with the superconducting critical temperature T c is observed under pressure. Moreover, the superconducting order parameter in T d-MoTe2 is determined to have 2-gap s-wave symmetry. We also exclude time-reversal symmetry breaking in the superconducting state with zero-field µSR experiments. Considering the strong suppression of T c in MoTe2 by disorder, we suggest that topologically non-trivial s +- state is more likely to be realized in MoTe2 than the topologically trivial s ++ state.

9.
Mol Genet Metab ; 120(3): 190-197, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28162992

RESUMO

OBJECTIVE: Assess current management practices of phenylketonuria (PKU) clinics across the United States (US) based on the key treatment metrics of blood phenylalanine (Phe) concentrations and blood Phe testing frequency, as well as patient adherence to their clinic's management practice recommendations. METHODS: An online survey was conducted with medical professionals from PKU clinics across the US from July to September 2015. Forty-four clinics participated in the survey and account for approximately half of PKU patients currently followed in clinics in the US (Berry et al., 2013). RESULTS: The majority of PKU clinics recommended target blood Phe concentrations to be between 120 and 360µM for all patients; the upper threshold was relaxed by some clinics for adult patients (from 360 to 600µM) and tightened for patients who are pregnant/planning to become pregnant (to 240µM). Patient adherence to these recommendations (percentage of patients with blood Phe below the upper recommended threshold) was age-dependent, decreasing from 88% in the 0-4years age group to 33% in adults 30+ years. Patient adherence to recommendations for blood testing frequency followed a similar trend. Higher staffing intensity (specialists per 100 PKU patients) was associated with better patient adherence to clinics' blood Phe concentrations recommendations. CONCLUSION: Clinic recommendations of target blood Phe concentrations in the US are now stricter compared to prior years, and largely reflect recent guidelines by the American College of Medical Genetics and Genomics (Vockley et al., 2014). Adherence to recommended Phe concentrations remains suboptimal, especially in older patients. However, despite remaining above the guidelines, actual blood Phe concentrations in adolescents and adults are lower than those reported in the past (Walter et al., 2002; Freehauf et al., 2013). Continued education and support for PKU patients by healthcare professionals, including adequate clinic staffing, are needed to improve adherence. Future research is needed to understand how to improve adherence to reduce the number of patients lost to follow-up, as the findings of this and similar surveys do not address how to keep patients in clinic.


Assuntos
Cooperação do Paciente/estatística & dados numéricos , Fenilalanina/sangue , Fenilcetonúrias/metabolismo , Adolescente , Adulto , Fatores Etários , Instituições de Assistência Ambulatorial , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Pessoal de Saúde/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Inquéritos e Questionários , Estados Unidos , Adulto Jovem
10.
Dalton Trans ; 45(4): 1737-45, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26701123

RESUMO

Complexes with purely pyridine-based macrocycles are rarely studied in photo(electro)catalysis. We synthesized and investigated macrocycles, in which two 2,2'-bipyridine (bpy) units are linked twice by two cyano-methylene groups, to yield the basic tetradentate, bipyridine based ligand framework (pyr). The protons in the bridges were substituted to obtain derivatives with one (pyr-alk) or two (pyr-alk2) alkyl-chains, respectively. We present the crystal structures of the mono-pentylated and the cis-dibutylated ligands. The corresponding Co(II) complexes [Co(II)(OH2)2(pyr)], [Co(II)Br(HOMe)(pyr-bu)], [Co(II)Br2(cis-pyr-bu2)] and [Co(II)Br2(trans-pyr-bu2)] were prepared, their physico-chemical properties elucidated and their crystal structures determined. X-ray analyses revealed for the latter three complexes distorted octahedral coordination and a fairly planar {Co(II)(pyr)} macrocyclic scaffold. The axial bromides in [Co(II)Br(HOMe)(pyr-bu)], [Co(II)Br2(cis-pyr-bu2)] and [Co(II)Br2(trans-pyr-bu2)] are weakly bound and dissociate upon dissolution in water. While the alkylated complexes are paramagnetic and feature Co(II) d(7) high spin configurations, the unsubstituted complex [Co(II)(OH2)2(pyr)] displays a rare Co(II) low spin configuration. The electronic ground states of [Co(II)Br2(cis-pyr-bu2)] and [Co(II)Br2(trans-pyr-bu2)] are similar, as evident from the almost identical UV/vis spectra. Electrochemical analyses show redox-non-innocent ligand frameworks. All complexes are highly robust and efficient H(+) reducing catalysts. In the presence of [Ru(bpy)3]Cl2 as a photosensitizer and TCEP/NaHasc as a sacrificial electron donor and shuttle, turnover numbers (TONs, H2/Co) up to 22 000 were achieved.

11.
Nat Commun ; 6: 8863, 2015 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-26548650

RESUMO

The superconducting gap structure in iron-based high-temperature superconductors (Fe-HTSs) is non-universal. In contrast to other unconventional superconductors, in the Fe-HTSs both d-wave and extended s-wave pairing symmetries are close in energy. Probing the proximity between these very different superconducting states and identifying experimental parameters that can tune them is of central interest. Here we report high-pressure muon spin rotation experiments on the temperature-dependent magnetic penetration depth in the optimally doped nodeless s-wave Fe-HTS Ba0.65Rb0.35Fe2As2. Upon pressure, a strong decrease of the penetration depth in the zero-temperature limit is observed, while the superconducting transition temperature remains nearly constant. More importantly, the low-temperature behaviour of the inverse-squared magnetic penetration depth, which is a direct measure of the superfluid density, changes qualitatively from an exponential saturation at zero pressure to a linear-in-temperature behaviour at higher pressures, indicating that hydrostatic pressure promotes the appearance of nodes in the superconducting gap.

12.
JIMD Rep ; 21: 23-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25712380

RESUMO

Maternal phenylketonuria (MPKU) is a well-recognized complication of PKU and one of the most potent teratogenic syndromes of pregnancy. Virtually all offspring from untreated pregnancies in women with classic PKU have intellectual disabilities and microcephaly. Congenital heart disease and intrauterine growth retardation occur many times more often than expected in the general population. Control of maternal blood phenylalanine during pregnancy prevents most if not all of these complications. Previous studies demonstrated the benefits of treatment in terms of birth parameters and early development. In this study, physical examinations, a medical history, and neuropsychological evaluation were obtained in 47 children from 24 mothers with PKU who received treatment during pregnancy. Mothers were interviewed and administered an abbreviated IQ test. Associations between maternal factors and offspring outcomes were also analyzed.The 21 male and 26 female offspring ranged in age from 1 month to 26 years with 21 (62%) over 6 years. Results indicated mean intercanthal distances above the 70th percentile. Microcephaly was present in 19% of offspring, with head circumference below the third percentile. None of the offspring had cardiac anomalies. Mean offspring IQ was 94 ± 19, with 12% performing in the range of intellectual disability (IQ < 70). Among children >5 years of age, 25% had learning disabilities, 31% had attention deficit hyperactivity disorder (ADHD), 22% were on ADHD medication, and 34% had a diagnosis of anxiety and/or depression. Among the 24 mothers, 12 reported following the diet for PKU. Only one woman on diet had a blood phenylalanine concentration <360 µmol/L (recommended range) and the majority had indications of poor nutritional status. Mean maternal Full Scale IQ was 94 ± 16 (range = 61-117), with 25% performing in the borderline intellectual range (IQ < 85). Verbal IQ was significantly lower than Performance IQ (p = 0.01, CI 2.7, 16.1). On the self-report Beck Depression Inventory, Second Edition, 25% received scores indicating mild to moderate depression, and on the Beck Anxiety Inventory, 46% reported mild to moderate anxiety. Offspring IQ correlated with maternal metabolic control during pregnancy (r = 0.51), maternal IQ (r = -0.62), and socioeconomic position (r = -0.48). Offspring with ADHD, learning disabilities, or emotional disturbances were more likely to have mothers with anxiety and/or depression. To ensure optimal offspring outcomes, healthcare providers need to assess maternal nutrition, blood phenylalanine concentrations, cognitive abilities, and socioeconomic position. Interventions can then be initiated that reduce psychosocial stressors and enhance adherence to diet and positive parenting, which in turn can lead to better cognitive functioning, behavior, and emotional well-being in their children.

13.
Osteoporos Int ; 24(2): 501-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22525982

RESUMO

SUMMARY: This study evaluated bone health in adults with galactosemia. Associations between bone mineral density (BMD) and nutritional and biochemical variables were explored. Calcium level predicted hip and spine BMD, and gonadotropin levels were inversely associated with spinal BMD in women. These results afford insights into management strategies for these patients. INTRODUCTION: Bone loss is a complication of galactosemia. Dietary restriction, primary ovarian insufficiency in women, and disease-related alterations of bone metabolism may contribute. This study examined relationships between clinical factors and BMD in patients with galactosemia. METHODS: This cross-sectional sample included 33 adults (16 women) with classic galactosemia, mean age 32.0 ± 11.8 years. BMD was measured by dual-energy X-ray absorptiometry, and was correlated with age, height, weight, fractures, nutritional factors, hormonal status, and bone biomarkers. RESULTS: There was a significant difference in hip BMD between women and men (0.799 vs. 0.896 g/cm(2), p = 0.014). The percentage of subjects with BMD-Z <-2.0 was also greater for women than men [33 vs. 18 % (spine), 27 vs. 6 % (hip)], and more women reported sustaining fractures. Bivariate analyses yielded correlations between BMI and BMD-Z [at the hip in women (r = 0.58, p < 0.05) and spine in men (r = 0.53, p < 0.05)]. In women, weight was also correlated with BMD-Z (r = 0.57, p < 0.05 at hip), and C-telopeptides (r = -0.59 at spine and -0.63 hip, p < 0.05) and osteocalcin (r = -0.71 at spine and -0.72 hip, p < 0.05) were inversely correlated with BMD-Z. In final regression models, higher gonadotropin levels were associated with lower spinal BMD in women (p = 0.017); serum calcium was a significant predictor of hip (p = 0.014) and spine (p = 0.013) BMD in both sexes. CONCLUSIONS: Bone density in adults with galactosemia is low, indicating the potential for increased fracture risk, the etiology of which appears to be multifactorial.


Assuntos
Galactosemias/complicações , Osteoporose/etiologia , Absorciometria de Fóton/métodos , Adulto , Antropometria/métodos , Biomarcadores/sangue , Densidade Óssea/fisiologia , Cálcio/administração & dosagem , Cálcio/sangue , Estudos Transversais , Suplementos Nutricionais , Esquema de Medicação , Feminino , Galactosemias/sangue , Galactosemias/fisiopatologia , Articulação do Quadril/fisiopatologia , Hormônios/sangue , Humanos , Masculino , Osteoporose/sangue , Osteoporose/fisiopatologia , Fatores Sexuais , Vitamina D/administração & dosagem , Adulto Jovem
14.
J Phys Condens Matter ; 24(38): 382202, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-22945447

RESUMO

We report on a new iron selenide superconductor with a T(c) onset of 45 K and the nominal composition Li(x)(C(5)H(5)N)(y)Fe(2-z)Se(2), synthesized via intercalation of dissolved alkaline metal in anhydrous pyridine at room temperature. This superconductor exhibits a broad transition, reaching zero resistance at 10 K. Magnetization measurements reveal a superconducting shielding fraction of approximately 30%. Analogous phases intercalated with Na, K and Rb were also synthesized and characterized. The superconducting transition temperature of Li(x)(C(5)H(5)N)(y)Fe(2-z)Se(2) is clearly enhanced in comparison to those of the known superconductors FeSe(0.98) (T(c) ~ 8 K) and A(x)Fe(2-y)Se(2) (T(c) ~ 27-32 K) and is in close agreement with critical temperatures recently reported for Li(x)(NH(3))(y)Fe(2-z)Se(2). Post-annealing of intercalated material (Li(x)(C(5)H(5)N)(y)Fe(2-z)Se(2)) at elevated temperatures drastically enlarges the c-parameter of the unit cell (~44%) and increases the superconducting shielding fraction to nearly 100%. Our findings indicate a new synthesis route leading to possibly even higher critical temperatures for materials in this class: by intercalation of organic compounds between Fe-Se layers.

15.
Plant Physiol Biochem ; 55: 52-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22543106

RESUMO

Plants contain variable chemical compositions which play a role in direct defense against phytophagous insects. Glucosinolates (GSs) are the predominant secondary metabolites and defense compounds in brassicaceous species. As a consequence of co-evolution between adapted crucifer-feeding specialists and their associated host-plants, specific plant-insect interactions have developed in a divergent manner from non-adapted generalists. Therefore, generalist and specialist insects may provoke different insect-inducible plant responses. Here, we have investigated the specific biochemical and molecular plant responses of Arabidopsis thaliana (L.) induced by the generalist Spodoptera exigua (Hübner) and the specialist Pieris brassicae L. To get more detailed information about herbivore-mediated-specific plant responses in different chemotypes within one species, we used multiple plant lines with either the non-hydroxylated 3-methylsulfinylpropyl GS or the hydroxylated 3-hydroxypropyl GS in a comparable genetic background. Caterpillar feeding induced a stronger GS accumulation in the 3-hydroxypropyl GS chemotype than the 3-methylsulfinylpropyl GS chemotype, considering the overall insect-mediated changes in aliphatic and indole GS levels in all lines. Herbivory by the generalist S. exigua and the specialist P. brassicae had similar effects on biochemical and transcriptional response pattern. Contrary to the paradigm that specialists may minimize the induction of chemical defenses, we observed a higher elicitation of GSs by the specialist species. The accumulation of especially 1-methoxy-indol-3-ylmethyl GS and the induced gene transcripts by the two species point to an insect-mediated activation of the jasmonic acid signaling pathway in the plant lines.


Assuntos
Arabidopsis/parasitologia , Borboletas/fisiologia , Glucosinolatos/metabolismo , Spodoptera/fisiologia , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cromatografia Líquida de Alta Pressão , Comportamento Alimentar/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glucosinolatos/química , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Hidroxilação , Doenças das Plantas/parasitologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie
16.
Anaesthesist ; 60(1): 39-48, 2011 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-21063671

RESUMO

BACKGROUND: According to numerous pharmacoeconomic studies new anaesthesia techniques can improve recovery times and thus can have a positive economic impact on patient turnover. However, artificial study protocols do not always match real world situations and thus the practical impact of such studies remains unclear. MATERIAL AND METHODS: At 10 hospitals exclusively using sevoflurane as a volatile anaesthetic, the ad hoc implementation of desflurane was studied with respect to post-anaesthetic recovery times (primary endpoint) and postoperative outcome measured by the Quality of Recovery Score- (QoR-)40, on the first postoperative day was investigated. Randomization of patients undergoing elective surgical procedures under general anaesthesia with sevoflurane (n=186) or desflurane (n=176) was started immediately after a period of a few days after introducing the new drug to all participants. Except for the volatile anaesthetic the anaesthetic procedure was performed according to local standing operating procedures. RESULTS: All parameters indicating the immediate postanaesthetic recovery were superior in the patients receiving desflurane (mean±SD). Time to extubation was accelerated from 8.7±9.7 to 6.2±6.8 min. Times to recalling name and date of birth were accelerated by 2.6 and 3.8 min, respectively. Transferring the patients from the operating theatre to the post-anaesthetic recovery unit was 17.3±11.5 min after sevoflurane and 13.7±7.8 min after anaesthesia with desflurane. Eligibility for discharge according to a modified Aldrete score (White and Song 1999) was reached after 103±98 and 79±76 min, respectively. The postoperative recovery (QoR 40 questionnaire) did not differ 24 h later. DISCUSSION: The implementation of a new drug (here: desflurane to substitute sevoflurane) can improve speed of recovery immediately after termination of anaesthesia even after a very short period of introducing the new technique but has no positive long term effects. Thus, the results of this trial performed under a real world scenario (health service research) without tight standardization by an artificial study protocol supports the results originating from randomized controlled clinical trials.


Assuntos
Anestesia/normas , Anestesiologia/normas , Anestésicos Inalatórios , Isoflurano/análogos & derivados , Adolescente , Adulto , Idoso , Período de Recuperação da Anestesia , Desflurano , Uso de Medicamentos , Determinação de Ponto Final , Feminino , Alemanha , Hospitais , Humanos , Masculino , Éteres Metílicos , Pessoa de Meia-Idade , Alta do Paciente , Políticas , Sevoflurano , Fatores Socioeconômicos , Adulto Jovem
17.
Phys Chem Chem Phys ; 11(14): 2514-24, 2009 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-19325986

RESUMO

A well-defined model-catalyst approach has been utilized to study the formation and decomposition of nitrite and nitrate species on a model NO(x) storage material. The model system comprises BaAl(2x)O(1+3x) particles of different size and stoichiometry, prepared under ultrahigh-vacuum (UHV) conditions on Al(2)O(3)/NiAl(110). Adsorption and reaction of NO(2) has been investigated by molecular beam (MB) methods and time-resolved IR reflection absorption spectroscopy (TR-IRAS) in combination with structural characterization by scanning tunneling microscopy (STM). The growth behavior and chemical composition of the BaAl(2x)O(1+3x) particles has been investigated previously. In this work we focus on the effect of particle size and stoichiometry on the reaction with NO(2). Particles of different size and of different Ba(2+) : Al(3+) surface ion ratio are prepared by varying the preparation conditions. It is shown that at 300 K the reaction mechanism is independent of particle size and composition, involving initial nitrite formation and subsequent transformation of nitrites into surface nitrates. The coordination geometry of the surface nitrates, however, changes characteristically with particle size. For small BaAl(2x)O(1+3x) particles high temperature (800 K) oxygen treatment gives rise to particle ripening, which has a minor effect on the NO(2) uptake behavior, however. STM shows that the morphology of the particle system is largely conserved during NO(2) exposure at 300 K. The reaction is limited to the formation of surface nitrites and nitrates, which are characterized by low thermal stability and completely decompose below 500 K. As no further sintering occurs before decomposition, NO(2) uptake and release is a fully reversible process. For large BaAl(2x)O(1+3x) particles, aggregates with different Ba(2+) : Al(3+) surface ion ratio were prepared. It was shown that the stoichiometry has a major effect on the kinetics of NO(2) uptake. For barium-aluminate-like particles with high Al(3+) concentration, the formation of nitrites and nitrates on the BaAl(2x)O(1+3x) particles at 300 K is slow, and kinetically restricted to the formation of surface species. Only at elevated temperature (500 K) are surface nitrates converted into well-defined bulk Ba(NO(3))(2). This bulk Ba(NO(3))(2) exhibits substantially higher thermal stability and undergoes restructuring and sintering before it decomposes at 700 K. For Ba(2+)-rich BaAl(2x)O(1+3x) particles, on the other hand, nitrate formation occurs at a much higher rate than for the barium-aluminate-like particles. Furthermore, nitrate formation is not limited to the surface, but NO(2) exposure gives rise to the formation of amorphous bulk Ba(NO(3))(2) particles even at 300 K.

18.
Commun Agric Appl Biol Sci ; 71(2 Pt B): 507-15, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17385519

RESUMO

Due to the sessile nature of plants they have to cope up dynamically with diverse biotic and abiotic stressors. Plants developed diverse, complex defense mechanisms for dealing with their enemies, including the glucosinolate(GS)-myrosinase system of the Brassicaceae and other families of the order Brassicales. GS are classified by their precursor amino acid and aliphatic, aromatic, and indolyl GS are distinguished. Indolyl GS are widely distributed in Arabidopsis thaliana (L.) ecotypes and the Brassicaceae family, but the presence of aliphatic GS is variable and under strong genetic control. There are only few studies paying attention to the impact of certain GS on insect resistance. Due to this, we have investigated the plant resistance of A. thaliana ecotypes with different aliphatic profiles against two specialized insects. For the experiments we selected 20 ecotypes, divided into three groups after HPLC analysis: containing 1) methylsulfinyl, 2) 3-hydroxypropyl, and 3) allyl GS. As herbivore insects the generalist Spodoptera exigua Hübner and the specialist Pieris brassicae L. were selected. The selected A. thaliana ecotype groups were different suitable for consumption, but similar for both insect species. In general, the percentage weight gain of larvae on A. thaliana plants containing 3-hydroxypropyl GS and allyl GS was significantly higher for both insect species, the specialist and the generalist, compared to methylsulfinyl GS containing ecotypes. But the tendency was stronger for P. brassicae than for S. exigua. Additionally, we used simple correlation to examine the relationship between insect feeding and the GS contents in the ecotypes. It can be concluded that 3-hydroxypropyl GS containing ecotypes were less resistant than ecotypes with methyl-sulfinyl GS as main compounds. Weight gain by S. exigua was statistically significant negatively related to constitutive GS levels of methylsulfinyl GS containing ecotypes. There was also a negative relation to constitutive GS levels of methylsulfinyl GS containing ecotypes for P. brassicae but less strong and not statistically significant. A reason for a better host plant suitability of ecotypes containing 3-hydroxypropyl GS might be the short chemical structure and/or different reactivity of this compound compared to ecotypes containing methylsulfinyl GS.


Assuntos
Arabidopsis/química , Arabidopsis/genética , Borboletas/efeitos dos fármacos , Glucosinolatos/farmacologia , Controle de Insetos/métodos , Spodoptera/efeitos dos fármacos , Animais , Borboletas/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Comportamento Alimentar , Expressão Gênica , Genótipo , Glucosinolatos/análise , Interações Hospedeiro-Parasita , Controle Biológico de Vetores , Especificidade da Espécie , Spodoptera/crescimento & desenvolvimento , Aumento de Peso
19.
Commun Agric Appl Biol Sci ; 71(2 Pt A): 215-23, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17390796

RESUMO

Rain and hail during ripening and harvesting season can cause yield losses up to 90 % in sweet cherry cultivations in Germany. Particularly, high yield losses after precipitation are due to the cracking and the following rotting process through bacteria and fungi's. In order to protect the crop and improve cherry quality they can be treated with chemicals dried or healthier covered with rain shelters. To date the cracking phenomenon of cherries is still not clearly understood. Therefore, in the present study the cracking resistance of three cherry varieties under different conditions was observed. We used 'Regina', 'Karina', and 'Summit' grafted on the rootstock GiSelA 5. The test-section in the field was covered with a plastic-foil (pc) as rain shelter and a bird net, whereby the control (c) was covered with a bird protection-net only. The cherry varieties have been harvested, weight and sorted into undamaged, rotten and cracked fruits. In order to compare the varieties under equal conditions the cracking sensitivity was also tested under laboratory conditions with the method from CHRISTENSEN (1996). The average yield per tree was significantly higher in the pc treatment in 'Summit' and 'Regina' than in the control. Furthermore, the average weight of rotten fruits per tree in these varieties was in c, without rain shelter, about two to three times higher as in the pc treatment. There was no significant difference in yield and rotten fruits among treatments in 'Karina'. But the percentage of cracked fruits between the cultivation methods was significant different. Hereby improvement of cherry quality was observed in the pc treatment with reduced numbers of useless fruits. Under field conditions 'Karina' was at least susceptible to cracking resistance followed by 'Regina' and 'Summit'. In the laboratory Cracking Test the result was different. Here, the variety 'Summit' showed the best cracking resistance compared to the other varieties. According to the method of CHRISTENSEN (1996) it was impossible to calculate a Cracking Index (CI) from 'Summit' because of a too little number of cracked fruits. The CI of 'Karina' was 22 under cover and 36.8 in the control without cover. 'Regina' performed better with a CI from 6.8 under plastic cover compared to 15.6 in the control. Therefore, the cracking susceptibility of varieties was different under field and laboratory conditions. In conclusion the distribution of the raindrops on the outer layers of the cherries, the ingredients (sugar) and morphology of cherries (fruit firmness) play an important role in the cracking process. The result with different cultivation methods and the different reaction of the fruits in the Cracking Index trial relate to morphological dissimilarities of tested varieties. Using rain shelters can clearly reduce the cracking of cherries and the following rotting process.


Assuntos
Agricultura/métodos , Conservação de Alimentos/métodos , Prunus , Chuva , Comportamento do Consumidor , Manipulação de Alimentos/métodos , Plásticos , Prunus/fisiologia , Paladar
20.
J Inherit Metab Dis ; 27(2): 145-55, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15159645

RESUMO

Women with phenylketonuria (PKU) must follow a strict low-phenylalanine diet during pregnancy in order to protect the fetus from the deleterious effects of high maternal blood phenylalanine. The Resource Mothers Study of Maternal PKU was undertaken to determine whether a home visitation programme was effective in helping women with PKU attain blood phenylalanine control earlier during pregnancy. Resource Mothers were trained to provide social support and practical assistance to women with PKU during pregnancy. Eight metabolic clinics in the United States participated in the study. Women with PKU who were planning pregnancy or already pregnant were enrolled in the study and were treated with a low-phenylalanine diet aimed at controlling blood phenylalanine to 120-360 micromol/L. They were randomly assigned to receive the services of a Resource Mother (RM group) or to a control group. Fifty women were enrolled, and accounted for 44 pregnancies which resulted in 28 live births, and 6 spontaneous abortions. Ten women are currently pregnant and another 6 have not become pregnant. Fifty-six percent of enrolled women began the diet prior to becoming pregnant. Fifty-three percent of women in the Resource Mother group were in metabolic control by 10 weeks gestation as compared to 39% in the control group. In addition, women who began diet after pregnancy and had a Resource Mother attained metabolic control earlier (mean gestational age of 22.4 weeks in the RM group vs 29.8 weeks in the control group). There was no difference in birth measurement z -scores of offspring born to women in the RM group compared to controls. All but 4 women rated themselves as feeling worse about the diet at the end of pregnancy than at the beginning, and few women in either group remained on diet after delivery.


Assuntos
Doenças Fetais/prevenção & controle , Grupo Associado , Fenilcetonúrias/dietoterapia , Complicações na Gravidez/dietoterapia , Cuidado Pré-Natal/organização & administração , Feminino , Idade Gestacional , Humanos , Cooperação do Paciente , Fenilalanina/sangue , Fenilcetonúrias/metabolismo , Fenilcetonúrias/psicologia , Gravidez , Complicações na Gravidez/metabolismo , Complicações na Gravidez/psicologia , Resultado da Gravidez , Avaliação de Programas e Projetos de Saúde , Apoio Social
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