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1.
Animal ; 18(6): 101168, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38762992

RESUMO

Heat stress (HS) negatively impacts a variety of production parameters in growing pigs; however, the impact of biological sex on the HS response is largely unknown. To address this, 48 crossbred barrows and gilts (36.8 ± 3.7 kg BW) were individually housed and assigned to one of three constant environmental conditions: (1) thermoneutral (TN) (20.8 ± 1.6 °C; 62.0 ± 4.7% relative humidity; n = 8/sex), (2) HS (39.4 ± 0.6 °C; 33.7 ± 6.3% relative humidity) for 1 d (HS1; n = 8/sex), or (3) or for 7 d (HS7; n = 8/sex). As expected, HS increased rectal temperature (Tr) following 1 d of HS (1.0 °C; P < 0.0001) and 7 d of HS (0.9 °C; P < 0.0001). By 7 d, heat-stressed gilts were cooler than barrows (0.4 °C; P = 0.016), despite identical heating conditions. There was a main effect of sex such that barrows had higher Tr than gilts (P = 0.031). Heat-stressed pigs on d 1 had marked reductions in feed intake and BW compared to TN (P < 0.0001). One day of HS resulted in negative gain to feed (G:F) in barrows and gilts and was reduced compared to TN (P < 0.0001). Notably, following 1 d of HS, the variability of G:F was greater in gilts than in barrows. Between 1 and 7 d of HS, G:F improved in barrows and gilts and were similar to TN pigs, even though HS barrows had higher Tr than gilts over this period. Heat stress for 1 and 7 d reduced empty gastrointestinal tract weight compared to TN (P < 0.0001). Interestingly, HS7 gilts had decreased gastrointestinal tract weight compared to HS1 gilts (2.43 vs 2.72 kg; P = 0.03), whereas it was similar between HS1 and HS7 barrows. Lastly, a greater proportion of gastrointestinal contents was in the stomach of HS1 pigs compared to TN and HS7 (P < 0.05), which is suggestive of decreased gastric emptying. Overall, HS barrows maintained an elevated Tr compared to HS gilts through the duration of the experiment but also maintained similar growth and production metrics compared to gilts, despite this higher temperature.


Assuntos
Resposta ao Choque Térmico , Temperatura Alta , Animais , Feminino , Masculino , Suínos/fisiologia , Suínos/crescimento & desenvolvimento , Temperatura Alta/efeitos adversos , Resposta ao Choque Térmico/fisiologia , Temperatura Corporal , Transtornos de Estresse por Calor/veterinária , Fatores Sexuais , Doenças dos Suínos , Sus scrofa/fisiologia , Sus scrofa/crescimento & desenvolvimento
2.
J Dairy Sci ; 106(8): 5825-5834, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37349209

RESUMO

Heat stress (HS) markedly affects postabsorptive energetics and protein metabolism. Circulating urea nitrogen increases in multiple species during HS and it has been traditionally presumed to stem from increased skeletal muscle proteolysis; however, this has not been empirically established. We hypothesized HS would increase activation of the calpain and proteasome systems as well as increase degradation of autophagosomes in skeletal muscle. To test this hypothesis, lactating dairy cows (~139 d in milk; parity ~2.4) were exposed to thermal neutral (TN) or HS conditions for 7 d (8 cows/environment). To induce HS, cattle were fitted with electric blankets for the duration of the heating period and the semitendinosus was biopsied on d 7. Heat stress increased rectal temperature (1.3°C) and respiratory rate (38 breaths per minute) while it decreased dry matter intake (34%) and milk yield (32%). Plasma urea nitrogen (PUN) peaked following 3 d (46%) and milk urea nitrogen (MUN) peaked following 4 d of environmental treatment and while both decreased thereafter, PUN and MUN remained elevated compared with TN (PUN: 20%; MUN: 27%) on d 7 of HS. Contrary to expectations, calpain I and II abundance and activation and calpain activity were similar between groups. Likewise, relative protein abundance of E3 ligases, muscle atrophy F-box protein/atrogin-1 and muscle ring-finger protein-1, total ubiquitinated proteins, and proteasome activity were similar between environmental treatments. Finally, autophagosome degradation was also unaltered by HS. Counter to our hypothesis, these results suggest skeletal muscle proteolysis is not increased following 7 d of HS and call into question the presumed dogma that elevated skeletal muscle proteolysis, per se, drives increased AA mobilization.


Assuntos
Lactação , Complexo de Endopeptidases do Proteassoma , Gravidez , Feminino , Bovinos , Animais , Lactação/fisiologia , Proteólise , Complexo de Endopeptidases do Proteassoma/metabolismo , Calpaína/metabolismo , Calpaína/farmacologia , Leite/metabolismo , Resposta ao Choque Térmico , Músculo Esquelético/metabolismo , Ureia/metabolismo , Dieta/veterinária
3.
J Photochem Photobiol B ; 189: 185-192, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30390525

RESUMO

In vitro standard methods are available and accepted worldwide to assess UVA protection of sunscreen products. Though, harmonisation of methods has made progress in the last decade, still two differing methods - one by FDA the other by ISO - are in use. In a multicentre study including 9 centres in Germany, 4 different commercial sunscreen products were assessed using both methods to discover their similarities and differences. UVA protection factor and Critical Wavelength were detected at various substrate type (sandblasted versus moulded PMMA plates), at different surface roughness of the plates as well as at different product application dose using two different irradiation spectra. Results: The strongest influence on UVA protection factor results from the surface roughness of the plates. Depending on the roughness (accepted range of 2 to 7 µm in the FDA method) a variability in the UVA protection factor of up to 25% was observed, while the much narrower definition of plate roughness by ISO (4.5 to 5.2 µm) had no relevant influence on the test results. Sandblasted plates in our assessment led to higher UVA protection factors and produced less scattered results compared to moulded plates. These differences were not pronounced. Application dose and spectra of the irradiation source were of negligible influence on UVA protection factor results for the investigated UV-filter combinations. The UVA protection factor which is the endpoint of the ISO method was found to be a parameter with a high potential to differentiate among different test products. The endpoint of the FDA method - the Critical Wavelength - was found to be an unambitious endpoint. Insensitivity to all described modifications of the method was observed. All investigated products performed similar and passed the Critical Wavelength criteria independent of method and parameters.


Assuntos
Técnicas In Vitro/métodos , Protetores Solares/normas , Raios Ultravioleta/efeitos adversos , Alemanha , Substâncias Protetoras/normas , Pele/efeitos da radiação , Propriedades de Superfície , Estados Unidos , United States Food and Drug Administration
4.
Opt Express ; 25(21): 26067-26075, 2017 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-29041268

RESUMO

Generating N single photons simultaneously is a formidable challenge due to the lack of deterministic single photon sources. Recent work [New J. Phys. 19, 063013 (2017] has proposed a relative multiplexing scheme that can enhance the N single photons probability with a minimum of active switching resources. We experimentally demonstrate relative temporal multiplexing on two photon sources with a 90% additional enhancement over the standard temporal multiplexing scheme demonstrated previously. 88 ± 11% visibility of Hong-Ou-Mandel quantum interference verifies the indistinguishability of the heralded single photons after the synchronization. This proof-of-principle demonstration points out the potential significance of the relative multiplexing scheme for large-scale photonic quantum information processing.

5.
Herz ; 41(2): 97-101, 2016 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-26838062

RESUMO

Transcatheter aortic valve implantation (TAVI) has become an established treatment for symptomatic aortic valve stenosis in inoperable patients and high-risk patients. In Germany the TAVI procedure has now surpassed the annual numbers of isolated surgical aortic valve replacement with a recent trend towards treatment of intermediate-risk patients; however, before TAVI can also be used in patients with lower surgical risk, studies are required to demonstrate the safety and efficacy of this method for this patient population.


Assuntos
Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas/estatística & dados numéricos , Complicações Pós-Operatórias/mortalidade , Substituição da Valva Aórtica Transcateter/mortalidade , Medicina Baseada em Evidências , Alemanha/epidemiologia , Humanos , Complicações Pós-Operatórias/prevenção & controle , Prevalência , Fatores de Risco , Taxa de Sobrevida , Substituição da Valva Aórtica Transcateter/estatística & dados numéricos , Resultado do Tratamento
6.
Phys Rev Lett ; 113(10): 100502, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25238340

RESUMO

We pose a randomized boson-sampling problem. Strong evidence exists that such a problem becomes intractable on a classical computer as a function of the number of bosons. We describe a quantum optical processor that can solve this problem efficiently based on a Gaussian input state, a linear optical network, and nonadaptive photon counting measurements. All the elements required to build such a processor currently exist. The demonstration of such a device would provide empirical evidence that quantum computers can, indeed, outperform classical computers and could lead to applications.

7.
Med Eng Phys ; 33(3): 340-6, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21130015

RESUMO

The spine is a complex structure that provides motion in three directions: flexion and extension, lateral bending and axial rotation. So far, the investigation of the mechanical and kinematic behavior of the basic unit of the spine, a motion segment, is predominantly a domain of in vitro experiments on spinal loading simulators. Most existing approaches to measure spinal stiffness intraoperatively in an in vivo environment use a distractor. However, these concepts usually assume a planar loading and motion. The objective of our study was to develop and validate an apparatus, that allows to perform intraoperative in vivo measurements to determine both the applied force and the resulting motion in three dimensional space. The proposed setup combines force measurement with an instrumented distractor and motion tracking with an optoelectronic system. As the orientation of the applied force and the three dimensional motion is known, not only force-displacement, but also moment-angle relations could be determined. The validation was performed using three cadaveric lumbar ovine spines. The lateral bending stiffness of two motion segments per specimen was determined with the proposed concept and compared with the stiffness acquired on a spinal loading simulator which was considered to be gold standard. The mean values of the stiffness computed with the proposed concept were within a range of ±15% compared to data obtained with the spinal loading simulator under applied loads of less than 5 Nm.


Assuntos
Teste de Materiais/métodos , Fenômenos Mecânicos , Movimento , Coluna Vertebral/fisiologia , Coluna Vertebral/cirurgia , Animais , Fenômenos Biomecânicos , Teste de Materiais/instrumentação , Ovinos , Suporte de Carga
8.
Skin Pharmacol Physiol ; 23(4): 201-12, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20215813

RESUMO

In the past, several attempts have been made to develop in vitro methods for determining protection against UV radiation. To date however, there is no broadly accepted method. Various known and unknown parameters influence the transmission measurements of scattering films, such as the multifaceted compositions of sunscreens, the technical limitations of measurement devices as well as the difficulty to apply very thin films of sunscreen in a reproducible manner throughout different laboratories. In vitro data were measured in this multicenter study to compare possible methodologies and strategies for an in vitro approach to the sun protection factor (SPF). This publication will not present a final in vitro SPF test method, but it will point out which technical side effects may influence such a method. Influential factors such as the quality of spectrophotometer used, the amount of product applied, pretreatment of samples, time and temperature of equilibration, size of the measured surface, the application process or the calculation on the basis of standardized data are presented and discussed. Finally, a reduction of the standard deviations within single laboratories could be realized for in vitro SPF testing, but no improvement of the interlaboratory comparison was obtained. The development of a valid and reliable SPF in vitro test still remains a challenge, and further work is necessary to develop a satisfactory method.


Assuntos
Teste de Materiais/normas , Luz Solar/efeitos adversos , Protetores Solares/química , Administração Cutânea , Humanos , Técnicas In Vitro , Teste de Materiais/métodos , Espectrofotometria Ultravioleta/métodos , Espectrofotometria Ultravioleta/normas , Protetores Solares/administração & dosagem , Raios Ultravioleta/efeitos adversos
9.
Acta Anaesthesiol Scand ; 54(4): 521-3, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20096021

RESUMO

Caffeine is a natural alkaloid methylxanthine that is found in various plants such as coffee or tea. Symptoms of a severe overdose may present with hypokalemia, hyponatremia, ventricular arrhythmias, hypertension followed by hypotension, respiratory failure, seizures, rhabdomyolysis, ventricular fibrillation and finally circulatory collapse. A 21-year-old woman called for the ambulance herself soon after the ingestion of about 10,000 mg of caffeine. At the arrival of the ambulance, the patient went into cardiac arrest almost immediately. After a total resuscitation period of 34 min including seven counter-shocks and 2 mg epinephrine, the patient was stable enough to be transferred to the hospital. The patient soon went into VF again and received two more counter-shocks and 1 mg epinephrine and finally an intravenous bolus dose of 300 mg amiodarone. The initial arterial blood gas showed pH at 6.47, lactate at 33 mmol/l and potassium level at 2.3 mmol/l. Unfortunately, no blood samples for caffeine analysis were taken. Three days after hospital admission, the patient developed myoclonus, which did not respond to medical treatment. Excessive intake of caffeine may produce arrhythmias and pronounced hypokalemia and ensuing ventricular fibrillation. In case of counter-shock-resistant VF, it can be necessary to give an early loading dose of amiodarone. Furthermore, it may be beneficial to replace the potassium as early as possible. Epinephrine and buffer solutions used during resuscitation may further decrease blood potassium levels and should be administrated cautiously. Epinephrine can be replaced by other vasopressor drugs, such as vasopressin without effects on beta-receptors.


Assuntos
Cafeína/intoxicação , Estimulantes do Sistema Nervoso Central/intoxicação , Amiodarona/uso terapêutico , Antiarrítmicos/uso terapêutico , Reanimação Cardiopulmonar , Cardioversão Elétrica , Eletrocardiografia , Evolução Fatal , Feminino , Parada Cardíaca/induzido quimicamente , Parada Cardíaca/patologia , Humanos , Hipopotassemia/induzido quimicamente , Hipóxia Encefálica/induzido quimicamente , Hipóxia Encefálica/patologia , Pneumonia/complicações , Fibrilação Ventricular/induzido quimicamente , Desequilíbrio Hidroeletrolítico/induzido quimicamente , Adulto Jovem
10.
Acta Neurol Scand ; 120(5): 347-52, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19744135

RESUMO

OBJECTIVE: To evaluate the long-term functional status and well-being in patients with chronic idiopathic polyneuropathy (CIP) in comparison to Guillain-Barré syndrome (GBS) and healthy controls. MATERIALS AND METHODS: Forty-two CIP and 42 GBS-patients were examined at median 5 and 6 years after disease onset and were compared with 50 healthy controls. The Fatigue Severity Scale (FSS), Visual Analogue Scale for pain (VAS), Disability Rating Index (DRI) and Medical Outcome Study 36-item short-form health status scale (SF-36) were used. Variables at onset and symptoms at follow-up were correlated with outcome measurements in GBS. RESULTS: Patients with CIP and GBS had more pain and disability than healthy controls. Additionally, CIP-patients were more fatigued than healthy controls. Patients with CIP were more fatigued [FSS 4.9 (SD 1.6) vs 3.8 (SD 1.8); P < 0.01] and disabled [DRI 4.1 (SD 2.3) vs 2.5 (SD 2.1); P = 0.05] than those with GBS. Physical functioning on the SF-36 was more impaired in CIP than GBS, compared with healthy controls. CONCLUSIONS: Patients with CIP and GBS seem to develop persistent impairment on long-term functional status and well-being, more clearly in CIP, reflecting the importance of long-term follow-up in further disease management.


Assuntos
Gerenciamento Clínico , Síndrome de Guillain-Barré/fisiopatologia , Nível de Saúde , Polineuropatias/fisiopatologia , Atividades Cotidianas , Adulto , Idoso , Doença Crônica , Progressão da Doença , Fadiga/etiologia , Feminino , Síndrome de Guillain-Barré/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Polineuropatias/complicações , Qualidade de Vida , Análise de Regressão , Índice de Gravidade de Doença , Inquéritos e Questionários , Resultado do Tratamento
11.
Endocr Relat Cancer ; 16(4): 1219-27, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19690016

RESUMO

A small subset of familial pancreatic endocrine tumors (PET) arises in patients with von Hippel-Lindau syndrome and these tumors may have an adverse outcome compared to other familial PET. Sporadic PET rarely harbors somatic VHL mutations, but the chromosomal location of the VHL gene is frequently deleted in sporadic PET. A subset of sporadic PET shows active hypoxia signals on mRNA and protein level. To identify the frequency of functionally relevant VHL inactivation in sporadic PET and to examine a possible prognostic significance we correlated epigenetic and genetic VHL alterations with hypoxia signals. VHL mutations were absent in all 37 PETs examined. In 2 out of 35 informative PET (6%) methylation of the VHL promoter region was detected and VHL deletion by fluorescence in situ hybridization was found in 14 out of 79 PET (18%). Hypoxia inducible factor 1alpha (HIF1-alpha), carbonic anhydrase 9 (CA-9), and glucose transporter 1 (GLUT-1) protein was expressed in 19, 27, and 30% of the 152 PETs examined. Protein expression of the HIF1-alpha downstream target CA-9 correlated significantly with the expression of CA-9 RNA (P<0.001), VHL RNA (P<0.05), and VHL deletion (P<0.001) as well as with HIF1-alpha (P<0.005) and GLUT-1 immunohistochemistry (P<0.001). These PET with VHL alterations and signs of hypoxia signalling were characterized by a significantly shortened disease-free survival. We conclude that VHL gene impairment by promoter methylation and VHL deletion in nearly 25% of PET leads to the activation of the HIF-pathway. Our data suggest that VHL inactivation and consecutive hypoxia signals may be a mechanism for the development of sporadic PET with an adverse outcome.


Assuntos
Metilação de DNA , Neoplasias das Glândulas Endócrinas/genética , Deleção de Genes , Mutação/genética , Neoplasias Pancreáticas/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Anidrase Carbônica IX , Anidrases Carbônicas/genética , Anidrases Carbônicas/metabolismo , Neoplasias das Glândulas Endócrinas/metabolismo , Neoplasias das Glândulas Endócrinas/patologia , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Pâncreas/metabolismo , Pâncreas/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Prognóstico , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Proteína Supressora de Tumor Von Hippel-Lindau/antagonistas & inibidores , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo
12.
Free Radic Biol Med ; 46(9): 1250-9, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19353781

RESUMO

Nitroalkene fatty acid derivatives manifest a strong electrophilic nature, are clinically detectable, and induce multiple transcriptionally regulated anti-inflammatory responses. At present, the characterization and quantification of endogenous electrophilic lipids are compromised by their Michael addition with protein and small-molecule nucleophilic targets. Herein, we report a trans-nitroalkylation reaction of nitro-fatty acids with beta-mercaptoethanol (BME) and apply this reaction to the unbiased identification and quantification of reaction with nucleophilic targets. Trans-nitroalkylation yields are maximal at pH 7 to 8 and occur with physiological concentrations of target nucleophiles. This reaction is also amenable to sensitive mass spectrometry-based quantification of electrophilic fatty acid-protein adducts upon electrophoretic resolution of proteins. In-gel trans-nitroalkylation reactions also permit the identification of protein targets without the bias and lack of sensitivity of current proteomic approaches. Using this approach, it was observed that fatty acid nitroalkenes are rapidly metabolized in vivo by a nitroalkene reductase activity and mitochondrial beta-oxidation, yielding a variety of electrophilic and nonelectrophilic products that could be structurally characterized upon BME-based trans-nitroalkylation reaction. This strategy was applied to the detection and quantification of fatty acid nitration in mitochondria in response to oxidative inflammatory conditions induced by myocardial ischemia-reoxygenation.


Assuntos
Alcenos/análise , Ácidos Graxos/metabolismo , Mitocôndrias Cardíacas/química , Nitrocompostos/análise , Animais , Bioquímica/métodos , Dimerização , Ácidos Graxos/química , Masculino , Mercaptoetanol/química , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Cardíacas/metabolismo , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/patologia , Oxirredução , Estresse Oxidativo , Oxirredutases/metabolismo , Ratos , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem
13.
Phys Rev Lett ; 103(24): 240504, 2009 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-20366191

RESUMO

We introduce and implement a technique to extend the quantum computational power of cluster states by replacing some projective measurements with generalized quantum measurements (POVMs). As an experimental demonstration we fully realize an arbitrary three-qubit cluster computation by implementing a tunable linear-optical POVM, as well as fast active feedforward, on a two-qubit photonic cluster state. Over 206 different computations, the average output fidelity is 0.9832+/-0.0002; furthermore the error contribution from our POVM device and feedforward is only of O(10(-3)), less than some recent thresholds for fault-tolerant cluster computing.

14.
Eur J Neurol ; 15(12): 1332-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19049550

RESUMO

BACKGROUND AND PURPOSE: The purpose of this study was to analyse the long-term impact of Guillain-Barré syndrome (GBS) on quality of life, and the relationship between clinical variables at disease onset and symptoms at follow-up to general health status. METHODS: Forty-two GBS patients were examined at median 6 years after disease onset and were compared with 50 healthy controls. The fatigue severity scale (FSS), visual analogue scale (VAS) for pain, disability rating index (DRI) and medical outcome study 36-item short-form health status scale (SF-36) were applied. Variables at onset and symptoms at follow-up were correlated with outcome measurements in GBS. RESULTS: VAS [2.9 (SD 3.3) vs. 1.5 (SD 1.9); P = 0.01] and DRI [2.5 (SD 2.1) vs. 1.0 (SD 1.5); P < 0.001] were significantly higher in patients with GBS, compared with healthy controls. Decreased physical functioning and general health were found on SF-36. Differences between GBS patients with shorter (<6 years) and longer (> or =6 years) follow-up after onset were not found. CONCLUSIONS: Relatively independent from various variables at onset, patients with GBS seem to have a reduced quality of life and functioning, and the distress seems to have become persistent after the first few years with improvement following the acute disease.


Assuntos
Síndrome de Fadiga Crônica/epidemiologia , Síndrome de Guillain-Barré/epidemiologia , Nível de Saúde , Dor/epidemiologia , Atividades Cotidianas/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica/psicologia , Avaliação da Deficiência , Síndrome de Fadiga Crônica/psicologia , Feminino , Síndrome de Guillain-Barré/psicologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Dor/psicologia , Medição da Dor , Qualidade de Vida/psicologia , Estresse Psicológico/epidemiologia , Inquéritos e Questionários , Tempo
15.
Phys Rev Lett ; 99(13): 130501, 2007 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17930565

RESUMO

We apply a notion of static renormalization to the preparation of entangled states for quantum computing, exploiting ideas from percolation theory. Such a strategy yields a novel way to cope with the randomness of nondeterministic quantum gates. This is most relevant in the context of optical architectures, where probabilistic gates are common, and cold atoms in optical lattices, where hole defects occur. We demonstrate how to efficiently construct cluster states without the need for rerouting, thereby avoiding a massive amount of conditional dynamics; we furthermore show that except for a single layer of gates during the preparation, all subsequent operations can be shifted to the final adapted single-qubit measurements. Remarkably, cluster state preparation is achieved using essentially the same scaling in resources as if deterministic gates were available.

16.
J Appl Microbiol ; 103(4): 1074-80, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17897212

RESUMO

AIM: To evaluate US Centers for Disease Control and Prevention recommended swab surface sample collection method for recovery efficiency and limit of detection for powdered Bacillus spores from nonporous surfaces. METHODS AND RESULTS: Stainless steel and painted wallboard surface coupons were seeded with dry aerosolized Bacillus atrophaeus spores and surface concentrations determined. The observed mean rayon swab recovery efficiency from stainless steel was 0.41 with a standard deviation (SD) of +/-0.17 and for painted wallboard was 0.41 with an SD of +/-0.23. Evaluation of a sonication extraction method for the rayon swabs produced a mean extraction efficiency of 0.76 with an SD of +/-0.12. Swab recovery quantitative limits of detection were estimated at 25 colony forming units (CFU) per sample area for both stainless steel and painted wallboard. CONCLUSIONS: The swab sample collection method may be appropriate for small area sampling (10 -25 cm2) with a high agent concentration, but has limited value for large surface areas with a low agent concentration. The results of this study provide information necessary for the interpretation of swab environmental sample collection data, that is, positive swab samples are indicative of high surface concentrations and may imply a potential for exposure, whereas negative swab samples do not assure that organisms are absent from the surfaces sampled and may not assure the absence of the potential for exposure. SIGNIFICANCE AND IMPACT OF THE STUDY: It is critical from a public health perspective that the information obtained is accurate and reproducible. The consequence of an inappropriate public health response founded on information gathered using an ineffective or unreliable sample collection method has the potential for undesired social and economic impact.


Assuntos
Bacillus/isolamento & purificação , Celulose , Manejo de Espécimes/métodos , Esporos Bacterianos/isolamento & purificação , Contagem de Colônia Microbiana , Materiais de Construção/microbiologia , Monitoramento Ambiental/métodos , Contaminação de Equipamentos , Sonicação , Aço Inoxidável , Propriedades de Superfície
17.
Eur J Neurol ; 14(6): 603-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17539935

RESUMO

The aim of this study was to evaluate the causes, prevalences, clinical manifestations of hospital-referred polyneuropathies, and evaluate neurophysiological findings in idiopathic polyneuropathy. From 2000 to 2005, 226 patients with polyneuropathy were examined. Polyneuropathy was diagnosed when symptoms, clinical- and neurophysiological findings were compatible with affection of at least two peripheral nerves. They were classified in symptomatic and idiopathic polyneuropathy after investigation. Clinical manifestations were evaluated for diabetes- (DPN), inflammatory- (INPN), hereditary- (HPN) and idiopathic polyneuropathy (IDPN). Neurophysiological findings were investigated in IDPN. 72% had a symptomatic polyneuropathy. Most frequent causes were diabetes mellitus (18%), inflammation, (16%) and hereditary (14%). Most common prevalences per 100,000 were as follows: IDPN, 21; DPN, 13 and HPN, 11. Predominating clinical manifestations were: sensory and motor in INPN, HPN and IPN; sensory in DPN. Pain was more present in IDPN and DPN than in others. In IDPN axonal demyelinating affection was present in 20%. Symptomatic polyneuropathy was common and diabetes mellitus, inflammation and hereditary were frequent causes. In IDPN, DPN, HPN and INPN different clinical patterns were found. Additionally, in IDPN axonal demyelinating affection was more frequent than previously reported.


Assuntos
Condução Nervosa/fisiologia , Nervos Periféricos/fisiopatologia , Polineuropatias/epidemiologia , Polineuropatias/etiologia , Polineuropatias/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Eletrodiagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Polineuropatias/classificação , Prevalência , Estudos Retrospectivos
18.
Skin Pharmacol Physiol ; 20(1): 57-64, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17035723

RESUMO

It is often debated that the protection against solar-induced erythema under real conditions is dependent upon the amount of sunscreen applied. It is believed that when too little is applied a lower sun protection than indicated on the label will result. The aim of this study was to quantify this effect. In this multicenter study, the influence of three different amounts (0.5, 1.0, 2.0 mg/cm(2)) of three commercial sunscreen products in three reliable test centers was investigated according to the test protocol of The International Sun Protection Factor Test Method. The main result was a linear dependence of the SPF on the quantity applied. Taking into consideration the volunteer-specific variations, an exponential dependence of confidence interval of the in vivo SPF and amount applied was found. The highest amount applied (2.0 mg/cm(2)) was linked to the lowest confidence intervals. Thus, from the point of view of producing reliable and reproducible in vivo results under laboratory conditions, the recommendation of this multicenter study is an application quantity of 2.0 mg/cm(2).


Assuntos
Eritema/prevenção & controle , Protetores Solares/uso terapêutico , Intervalos de Confiança , Relação Dose-Resposta a Droga , Eritema/etiologia , Humanos , Modelos Lineares , Protetores Solares/administração & dosagem , Raios Ultravioleta/efeitos adversos
19.
J Chem Phys ; 124(11): 114504, 2006 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-16555898

RESUMO

High-temperature, high-pressure Raman spectra were obtained from aqueous NaOH solutions up to 2NaOHH2O, with X(NaOH)=0.667 at 480 K. The spectra corresponding to the highest compositions, X(NaOH)> or =0.5, are dominated by H3O2-. An IR xi-function dispersion curve for aqueous NaOH, at 473 K and 1 kbar, calculated from the data of Franck and Charuel indicates that the OH- ion forms H3O2- by preferential H bonding with nonhydrogen-bonded OH groups. Raman spectra from wet to anhydrous, solid LiOH, NaOH, and KOH yield sharp, symmetric OH- stretching peaks at 3664, 3633, and 3596 cm(-1), respectively, plus water-related, i.e., H3O2-, peaks near LiOH, 3562 cm(-1), NaOH, 3596 cm(-1), and, KOH, 3500 cm(-1). Absence of H3O2- peaks from the solid assures that the corresponding melt is anhydrous. Raman spectra from the anhydrous melts yield OH- stretching peak frequencies: LiOH, 3614+/-4 cm(-1), 873 K; NaOH, 3610+/-2 cm(-1), 975 K; and, KOH, 3607+/-2 cm(-1), 773 K, but low-frequency asymmetry due to ion-pair interactions is present which is centered near 3550 cm(-1). The ion-pair-related asymmetry corresponds to the sole IR maximum near 3550 cm(-1) from anhydrous molten NaOH, at 623 K. Bose-Einstein correction of published low-frequency Raman data from molten LiOH revealed an acoustic phonon, near 205 cm(-1), related to restricted translation of OH- versus Li+, and an optical phonon, at 625 cm(-1) and tau approximately 0.05 ps, due to protonic precession and/or pendular motion. Strong H bonding between water and the O atom of OH- forms H3O2-, but the proton of OH- does not bond with H significantly. Large Raman bandwidths (aqueous solutions) are explained in terms of inhomogeneous broadening due to proton transfer in a double well. Vibrational assignments are presented for H3O2-.

20.
Sci Total Environ ; 367(1): 354-66, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16434084

RESUMO

Atmospheric concentrations of elemental mercury (Hg(0)), reactive gaseous Hg (RGM), and particulate Hg (pHg) concentrations were measured in Yellowstone National Park (YNP), U.S.A. using high resolution, real time atmospheric mercury analyzers (Tekran 2537A, 1130, and 1135). A survey of Hg(0) concentrations at various locations within YNP showed that concentrations generally reflect global background concentrations of 1.5-2.0 ng m(-3), but a few specific locations associated with concentrated geothermal activity showed distinctly elevated Hg(0) concentrations (about 9.0 ng m(-3)). At the site of intensive study located centrally in YNP (Canyon Village), Hg(0) concentrations did not exceed 2.5 ng m(-3); concentrations of RGM were generally below detection limits of 0.88 pg m(-3) and never exceeded 5 pg m(-3). Concentrations of pHg ranged from below detection limits to close to 30 pg m(-3). RGM and pHg concentrations were not correlated with any criteria gases (SO(2), NO(x), O(3)); however pHg was weakly correlated with the concentration of atmospheric particles. We investigated three likely sources of Hg at the intensive monitoring site: numerous geothermal features scattered throughout YNP, re-suspended soils, and wildfires near or in YNP. We examined relationships between the chemical properties of aerosols (as measured using real time, single particle mass spectrometry; aerosol time-of-flight mass spectrometer; ATOFMS) and concentrations of atmospheric pHg. Based on the presence of particles with distinct chemical signatures of the wildfires, and the absence of signatures associated with the other sources, we concluded that wildfires in the park were the main source of aerosols and associated pHg to our sampling site.


Assuntos
Poluentes Atmosféricos/análise , Ar/análise , Monitoramento Ambiental , Mercúrio/análise , Aerossóis , Ar/normas , Gases , Tamanho da Partícula , Estados Unidos
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