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1.
J Nurs Care Qual ; 39(4): 354-360, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38814724

RESUMO

BACKGROUND: The Clinical Nurse Leader (CNL) is a skilled clinician qualified in outcomes-based practice and quality improvement. Publications describe the CNL training, integration, and outcomes. However, CNL practice development and its impact has not been fully explored. PURPOSE: This review aimed to synthesize existing literature related to CNL practice development and identify what influences on the care environment and nursing care outcomes. METHODS: An integrative literature review was conducted in 5 bibliographic databases for sources published in English from January 2012 to March 2023. RESULTS: Fifteen publications identified 3 interrelated themes of CNL practice, outcomes, and practice development. Staff development needs were identified across various levels of expertise. CONCLUSION: There is a need to further explore CNL practice development and how it can impact the care environment and care outcomes.


Assuntos
Liderança , Desenvolvimento de Pessoal , Humanos , Enfermeiros Clínicos/educação , Melhoria de Qualidade
2.
Arch Pediatr ; 29(4): 253-257, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35351343

RESUMO

Neonatal screening for congenital hypothyroidism (CH) is based on the measurement of thyroid-stimulating hormone (TSH) in whole dried blood samples on filter paper in all newborns. The objective of screening for CH is to prevent mental retardation, which is irreversible in the event of a late diagnosis, by setting up prompt treatment (before day 15) with levothyroxine. The threshold value of TSH on filter paper on day 3 is 17 mIU/L in France in the GSP method (GSP, Genetic Screening Processor, Perkin Elmer): It is one of the highest thresholds used in the world. In many countries, the TSH threshold is between 6 and 12 mIU/L. Studies have found that a threshold of > 17 mIU/L may miss as much as 30% of cases of CH, with 30-80% of these being permanent CH. Recent studies suggest that mild CH (currently missed by the French TSH threshold) is associated with cognitive consequences if left untreated. An inverse relationship between TSH at screening (below the current threshold) and cognitive development at preschool or school age has been shown. These studies advocate for the evaluation of a lowering of the threshold of TSH on filter paper in France: (a) to determine the number of CH diagnoses with the new threshold and whether these "new cases" would be transitory or permanent; and (b) to analyze the cost-effectiveness of the strategy.


Assuntos
Hipotireoidismo Congênito , Triagem Neonatal , Hipotireoidismo Congênito/complicações , Hipotireoidismo Congênito/diagnóstico , França , Humanos , Recém-Nascido , Triagem Neonatal/métodos , Tireotropina
3.
Orphanet J Rare Dis ; 17(1): 58, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35172866

RESUMO

Central diabetes insipidus (CDI) is a rare condition, with significant impact on patient health and well-being. It is a chronic condition which usually requires meticulous long-term care. It can affect both children and adults. There is limited literature considering the needs and challenges inherent in providing high quality care to patients with CDI, across the care pathway. This paper seeks to address this gap by providing a unique and well-rounded understanding of clinical and healthcare systems-related challenges. It draws on insights from the literature, from direct clinical experience contributed by five clinicians as co-authors (providing insights from France, Ireland, Italy, Spain and the United Kingdom), and from patient perspectives provided through interviews with patient representatives from three patient organisations. We identify clinical challenges related to the diagnosis of CDI, including differentiating between other similar conditions and determining the underlying aetiology. Treatment is challenging, given the need to tailor medication to each patient's needs and ongoing management is required to ensure that patients continue to respond adequately to treatment. Ongoing support is required when patients switch between formulations. We also identify healthcare systems challenges related to limited awareness of CDI amongst primary care physicians and general paediatricians, and the need for highly skilled specialist care and appropriate workforce capacity. There is also a significant need for raising awareness and for the education of both healthcare professionals and patients about different aspects of CDI, with the aim of supporting improved care and effective patient engagement with healthcare professionals. We reflect on this information and highlight improvement opportunities. These relate to developing guidance to support patients, carers, primary care physicians and general paediatricians to identify clinical features earlier, and to consider CDI as a possible diagnosis when a patient presents with suggestive symptoms.


Assuntos
Diabetes Insípido Neurogênico , Diabetes Mellitus , Adulto , Criança , Atenção à Saúde , Pessoal de Saúde , Humanos , Qualidade da Assistência à Saúde , Inquéritos e Questionários
5.
Rev Sci Instrum ; 92(10): 105005, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34717435

RESUMO

Low intrinsic noise, high bandwidth, and high accuracy vector magnetometers are key components for many ground or space geophysical applications. Here, we report the design and the test of a 4He vector optically pumped magnetometer specifically dedicated to these needs. It is based on a parametric resonance magnetometer architecture operated in the Earth magnetic field with closed-loop compensation of the three components of the magnetic field. It provides offset-free vector measurements in a ±70 µT range with a DC to 1 kHz bandwidth. We demonstrate a vector sensitivity up to 130 fT/√Hz, which is about ten times better than the best available fluxgate magnetometers currently available for the same targeted applications.

6.
J Prof Nurs ; 37(1): 12-17, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33674082

RESUMO

Designation as an accredited school of nursing (SON) requires "…. a comprehensive framework for ensuring quality in nursing education programs" (NLN CNEA, 2016). Although standards for accreditation of baccalaureate and graduate nursing programs are defined by agencies such as the Commission on Collegiate Nursing Education (CCNE, 2018) and the National League for Nursing Commission for Nursing Education Accreditation (NLN CNEA) (NLN CNEA, 2016), methods for collecting, analyzing, or reporting data are not prescribed, resulting in wide variation in quality management processes among schools. The lack of a standardized approach can lead to inefficiencies, invalid or misleading data, and unnecessary stress for all involved in the quality management process (Hanna, Duvall, Turpin, Pendleton-Romig, & Parker, 2016). In contrast, hospitals and nursing homes frequently implement a quality assurance and performance improvement (QAPI) program, a well-defined, methodical approach to quality management. The QAPI model offers healthcare organizations a systematic, comprehensive, and data-driven strategy for maximizing outcomes (Centers for Medicare & Medicaid Services (CMS), 2016). Recognizing the need to improve and standardize the processes for data collection, analysis, and reporting, this paper describes how leaders at one accredited SON collaborated to translate CMS's QAPI model into the academic setting, establishing the foundation and mechanism to ensure the quality and integrity of the SON's outcomes.


Assuntos
Bacharelado em Enfermagem , Educação de Pós-Graduação em Enfermagem , Educação em Enfermagem , Acreditação , Medicare , Casas de Saúde , Melhoria de Qualidade , Estados Unidos
7.
Nurs Educ Perspect ; 41(5): 315-316, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32769845

RESUMO

Graduate nurses report feeling unprepared for accreditation site visits, including the promotion of a safe, functional, supportive environment to preserve safety and quality through the provision of care, treatment, and services for patients. To address this gap, an academic health system's department of quality and a school of nursing collaborated on a three-phase capstone course for senior-level BSN students. The course included simulation training for all students; volunteers performed Environment of Care rounds and patient care record audits in the hospital setting. Nineteen students, who performed 74 rounds and 193 audits, reported feeling more knowledgeable during site visits.


Assuntos
Bacharelado em Enfermagem , Treinamento por Simulação , Estudantes de Enfermagem , Humanos , Aprendizagem
8.
J Neuroimmunol ; 339: 577094, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31756640

RESUMO

BACKGROUND/PURPOSE: In anti-myelin associated glycoprotein (anti-MAG) neuropathies, there is evidence that anti-MAG antibodies are pathogenic but numerous studies report the absence or a weak correlation between the titers of these antibodies and disease course. In this study we assessed the relationships between MAG and glycosylated moieties located on Fc fragment of IgM anti-MAG. MATERIAL AND METHODS: IgM were extracted from the serum of 8 patients with anti-MAG neuropathy and in 2 patients with anti-MAG antibodies without anti-MAG neuropathy. Anti-MAG activity was performed with pre- and post-deglycosylated IgM extracts using indirect immunofluorescence (IIF) and ELISA. Sera from 49 patients with IgM monoclonal gammopathy without neurological disease were tested as control group (CG). Results were compared to clinical scores. For 4 patients the affinity constant of IgM with MAG was analyzed pre- and post-deglycosylated, using surface plasmon resonance technology (SPR). RESULTS: The relationships between MAG and glycosylated moieties of IgM anti-MAG were confirmed by kinetic and immunological assays. Deglycosylation resulted in a decrease in anti-MAG titers. Post-deglycosylation anti-MAG titers trended with changes in IgM titers and allowed quantifying anti-MAG antibodies without a saturation of the testing method. After deglycosylation, the titers better represented pathogenic activity and help to follow a given patient's clinical status prospectively. Six patients from CG (12.2%) had anti-MAG antibody titers over positive threshold: 1000 Bühlmann-Titer-Units (BTU) supporting the hypothesis of neutral intermolecular interactions between IgM and MAG. Deglycosylation allowed distinguishing infra clinical forms from neutral relationships forms, when the titers are weak but this assay remains essentially a diagnostic tool.


Assuntos
Autoanticorpos/sangue , Imunoglobulina M/sangue , Glicoproteína Associada a Mielina/sangue , Doenças do Sistema Nervoso/sangue , Doenças do Sistema Nervoso/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos
9.
J Comp Pathol ; 171: 19-23, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31540621

RESUMO

Proliferative, myxomatous change was identified in the cardiac valves (i.e. valvular endocardiosis) with extension into some cardiac walls (i.e. mural endocardiosis) of five tetras (four neon tetras [Paracheirodon innesi] and one rummynose tetra [Hemigrammus rhodostomus]). Review of cardiac sections from tetras (family Characiformes) submitted to two diagnostic laboratories revealed a prevalence of endocardiosis in tetras of 4.3% and 5.7%, respectively. In four cases, concurrent disease that could be a primary cause of death was not identified, and endocardiosis was considered the primary cause of death; in the fifth case, egg binding was present concurrently. This retrospective case series suggests that endocardiosis is a significant concern in fish of the family Characiformes.


Assuntos
Doenças dos Peixes/patologia , Doenças das Valvas Cardíacas/veterinária , Animais , Characidae , Doenças das Valvas Cardíacas/patologia , Estudos Retrospectivos
11.
Eur J Neurol ; 26(4): 631-638, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30431216

RESUMO

BACKGROUND AND PURPOSE: The usefulness of plexus magnetic resonance imaging (MRI) in the diagnosis of chronic inflammatory demyelinating polyradiculopathy (CIDP) without definite European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) electrodiagnostic criteria is currently unclear. METHODS: Data from consecutive patients with clinical manifestations suggesting CIDP, with or without (CIDP-D and CIDP-ND, respectively) definite EFNS/PNS electrodiagnostic criteria, and referred for plexus MRI in our imaging centre were retrospectively analysed. An expert committee of neurologists compared the level of suspicion of CIDP in CIDP-ND patients to the blinded/unblinded MRI findings. Plexus MRI was reviewed by a neuroradiologist blinded to the final diagnosis. RESULTS: In all, 38 patients were assessed with suspected CIDP-ND [7/38 (18%) probable; 13/38 (34%) possible; 18/38 (47%), no EFNS/PNS electrodiagnostic criteria], plus 10 with CIDP-D. Thirty-six of the 38 (95%) fulfilled clinical criteria of CIDP variants, including pure sensory neuropathy in 22/36 (61%). Plexus MRI showed abnormalities in 22/38 (58%) patients including increased nerve signal intensity on T2-weighted images in 22/22 (100%), nerve enlargement in 20/22 (91%) and contrast enhancement in 8/22 (36%). Plexus MRI enabled the expert committee's final diagnosis to be adjusted in 7/38 (18%) patients, and in conjunction with nerve conduction studies was a supportive criterion to classify 7/24 (29%) patients as definite CIDP. MRI abnormalities were more asymmetrical (P = 0.03) and less diffuse (P = 0.1) in CIDP-ND than in CIDP-D. CONCLUSIONS: Our observations suggest that plexus MRI makes a valuable contribution to the diagnosis of CIDP-ND patients. Further studies are needed to investigate inter-rater reliability of clinical and imaging criteria of CIDP in these patients, and the impact on outcomes.


Assuntos
Nervos Periféricos/diagnóstico por imagem , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Nervos Periféricos/fisiopatologia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico por imagem , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/fisiopatologia , Reprodutibilidade dos Testes , Estudos Retrospectivos
12.
Eur Ann Otorhinolaryngol Head Neck Dis ; 135(1): 21-24, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28941966

RESUMO

INTRODUCTION: Patients with Turner syndrome (TS) have craniofacial malformations, such as Eustachian tube hypoplasia and dysfunction and velar dysfunction, which foster acute otitis media. The aim of this study was to inventory pediatric otologic disorders in patients with TS at their first ENT consultation in our center. PATIENTS AND METHODS: We reviewed the ENT consultation data of pediatric TS patients followed in our center between 2005 and 2015: otoscopy, hearing threshold, and history of acute otitis media or ENT surgery. Data were compared according to karyotype: X monosomy (45,X), mosaic (45,X/46,XX), isochromosome (46,Xi [Xq]), X ring chromosome X (XrX), with Y material, and "other". RESULTS: Ninety patients, with mean age 11.9years (±4.8years) at first ENT consultation, were included: 29% showed tympanic abnormality on otoscopy, 21% had hearing loss, 24% had history of recurrent acute otitis media; 18% had undergone adenoidectomy, 24% T-tube insertion, and 5.6% tympanoplasty. No particular karyotype was associated with higher risk of hearing loss or acute otitis media. CONCLUSION: Patients with TS showed high prevalence of pediatric otologic disorders; they therefore require close and prolonged ENT follow-up.


Assuntos
Perda Auditiva/genética , Síndrome de Turner/genética , Criança , Pré-Escolar , Anormalidades Craniofaciais/genética , Tuba Auditiva/anormalidades , Feminino , Perda Auditiva Condutiva/genética , Perda Auditiva Neurossensorial/genética , Humanos , Cariotipagem , Otite Média/genética , Palato Mole/anormalidades , Estudos Retrospectivos , Síndrome de Turner/fisiopatologia , Membrana Timpânica/anormalidades
13.
Clin Microbiol Infect ; 24(1): 83.e1-83.e6, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28559002

RESUMO

OBJECTIVES: Prosthetic joint infections (PJI) are responsible for significant morbidity and mortality and their number continues to rise. Their management remains complex, especially the microbiological diagnosis. Besides 'homemade' tests developed by several teams, new molecular biology methods are now available with different analytical performance and usability. METHODS: We studied the performances of one of these tests: ITI® multiplex PCR (mPCR) by the Curetis® company and compared it to either 'optimized' culture or 16S rRNA PCR. We performed a retrospective multicentre study to assess the contributions of mPCR in the diagnosis of PJI. We randomly selected 484 intraoperative specimens among 1252 of various types (biopsy, bone, tissue around the prosthesis, synovial fluid) from 251 patients in seven different hospitals. Each sample was treated according to the recommendations of the manufacturer. RESULTS: In all, 154 out of 164 (93.9%) samples negative in culture were negative with the mPCR. Among the 276 positive samples in culture, 251 (90.9%) were monomicrobial, of which 119 (47.4%) were positive with the mPCR, and 25 (9.1%) were polymicrobial, of which 12 (48%) were positive with the mPCR. The concordance rate of mPCR with culture was 58.1% (53.6%-62.7%) and the concordance rate with 16S rRNA PCR was 70.1% (65.5%-74.6%). CONCLUSION: This new standardized molecular test showed a lack of detection when the bacterial inoculum was low (number of positive media per sample and number of colonies per media) but can be useful when patients have received antibiotic therapy previously.


Assuntos
Prótese Articular/microbiologia , Staphylococcus aureus Resistente à Meticilina/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/diagnóstico , Proteínas de Bactérias/genética , Humanos , Resistência a Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Proteínas de Ligação às Penicilinas/genética , Infecções Relacionadas à Prótese/mortalidade , RNA Ribossômico 16S/genética , Estudos Retrospectivos , Infecções Estafilocócicas/microbiologia
14.
J Mater Chem B ; 5(40): 8105-8114, 2017 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-32264649

RESUMO

Here we detail the fabrication and testing of artificial muscles fabricated from composites of the natural biopolymer silk fibroin and conducting polymers. Aligned nanofiber bundles of silk that mimic the structure of skeletal muscles were produced via electrospinning, and the fibers were infused with conducting polymers using chemical and electrochemical in situ polymerization methods. The resulting bundles of individual, electroactive fibers underwent electromechanical actuation in biologically-relevant electrolyte solutions when low potentials were applied, thus mimicking the contractile function of native muscles. The fabrication methods, bulk mechanical properties, stress and strain generation, and stability under repeated actuation for fiber bundles coated with different conducting polymer formulations are presented.

15.
Int J Neurosci ; 127(6): 516-523, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27412148

RESUMO

BACKGROUND: In patients with autoimmune diseases who still derive benefit from high dose intravenous immunoglobulin (IVIg) treatment, some physicians resort to subcutaneous (SC) Ig as a replacement therapy. OBJECTIVE: To collect quality of life (QoL) and tolerance data on SCIg in patients for whom the switch from IVIg to SCIg is essential to maintain treatment. METHODS: This observational study included patients with either idiopathic inflammatory myopathies (IIM) or chronic dysimmune peripheral neuropathies (CDPN) treated with IVIg, who had been switched to SCIg administration for at least three months. The main objective was to describe the impact of SCIg on QoL after six months, using the generic Short-Form 36 questionnaire (SF-36). The secondary objectives were to evaluate SCIg tolerance and clinical efficiency. RESULTS: Eight centres recruited 12 IIM patients and two centres recruited 11 CDPN patients. Neither the physical nor the mental health SF-36 component summaries showed any QoL deterioration during the six-month study period and all IIM and CDPN patients remained clinically stable during the same period. The most frequent adverse effects were injection site reactions (50%), cutaneous tissue disorders (18.2%), and nervous system disorders (13.6%). Two serious adverse events (myocarditis and cerebrovascular accident) occurred in two patients. CONCLUSION: In these rare inflammatory diseases, high dose SCIg administration (which can be home based) has no deleterious effect on patient QoL. It appears to be a safe and efficient alternative to hospital-based IVIg.


Assuntos
Imunoglobulinas/administração & dosagem , Fatores Imunológicos/administração & dosagem , Miosite/tratamento farmacológico , Miosite/psicologia , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/psicologia , Qualidade de Vida/psicologia , Adulto , Idoso , Creatina Quinase/sangue , Tolerância a Medicamentos , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
16.
West J Nurs Res ; 39(5): 660-673, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27534423

RESUMO

Patient safety has been at the forefront of nursing research since the release of the Institute of Medicine's report estimating the number of preventable adverse events in hospital settings; yet no research to date has incorporated the perspectives of bedside nurses using classical grounded theory (CGT) methodology. This CGT study explored the perceptions of bedside registered nurses regarding patient safety in adult acute care hospitals. Data analysis used three techniques unique to CGT-the constant comparative method, coding, and memoing-to explore the values, realities, and beliefs of bedside nurses about patient safety. The analysis resulted in a substantive theory, Exerting Capacity, which explained how bedside nurses balance the demands of keeping their patients safe. Exerting Capacity has implications for health care organization leaders, nursing leaders, and bedside nurses; it also has indications for future research into the concept of patient safety.


Assuntos
Teoria Fundamentada , Recursos Humanos de Enfermagem Hospitalar/psicologia , Segurança do Paciente , Gestão da Segurança , Adulto , Atitude do Pessoal de Saúde , Tomada de Decisões , Feminino , Hospitais , Humanos , Masculino , Cultura Organizacional
17.
Rev Neurol (Paris) ; 172(12): 766, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27919330
18.
Appl Opt ; 55(20): 5399-407, 2016 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-27409317

RESUMO

Recent research has shown that using multiple diverse-bandgap photovoltaic (PV) cells in conjunction with a spectrum splitting optical system can significantly improve PV power generation efficiency. Although volume Bragg gratings (VBGs) can serve as effective spectrum splitters, the inherent dispersion of a VBG can be detrimental given a broad-spectrum input. The performance of a single holographic spectrum splitter element can be improved by utilizing multiple single volume gratings, each operating in a slightly different spectral band. However, care must be taken to avoid inter-grating coupling effects that limit the ultimate performance. This work explores broadband two-grating holographic optical elements (HOEs) in multiplexed (single element) and sandwiched-grating arrangements. Particle swarm optimization is used to tailor these systems to the solar spectrum, taking into account both efficiency and dispersion. Both multiplexed and sandwiched two-grating systems exhibit performance improvements over single-grating solutions, especially when reduced dispersion is required. Under a ±2° constraint on output angular spread from wavelength dispersion, sandwiched-, multiplexed-, and single-grating systems exhibit power conversion efficiencies of 82.1%, 80.9%, and 77.5%, respectively, compared to an ideal bandpass spectrum splitter. Dispersion performance can be further improved by employing more than two VBGs in the spectrum splitter, but efficiency is compromised by additional cross-coupling effects. Multiplexed-grating systems are especially susceptible to these effects, but have the advantage of utilizing only a single HOE.

19.
mBio ; 6(4)2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26307166

RESUMO

UNLABELLED: Describing the viral diversity of wildlife can provide interesting and useful insights into the natural history of established human pathogens. In this study, we describe a previously unknown picornavirus in harbor seals (tentatively named phopivirus) that is related to human hepatitis A virus (HAV). We show that phopivirus shares several genetic and phenotypic characteristics with HAV, including phylogenetic relatedness across the genome, a specific and seemingly quiescent tropism for hepatocytes, structural conservation in a key functional region of the type III internal ribosomal entry site (IRES), and a codon usage bias consistent with that of HAV. IMPORTANCE: Hepatitis A virus (HAV) is an important viral hepatitis in humans because of the substantial number of cases each year in regions with low socioeconomic status. The origin of HAV is unknown, and no nonprimate HAV-like viruses have been described. Here, we describe the discovery of an HAV-like virus in seals. This finding suggests that the diversity and evolutionary history of these viruses might be far greater than previously thought and may provide insight into the origin and pathogenicity of HAV.


Assuntos
Hepatovirus/genética , Hepatovirus/isolamento & purificação , Filogenia , Focas Verdadeiras/virologia , Animais , Códon , Genoma Viral , Genótipo , Vírus da Hepatite A Humana/genética , Hepatovirus/fisiologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Fígado/virologia , Pulmão/virologia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Baço/virologia , Replicação Viral
20.
Appl Opt ; 54(20): 6244-53, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26193400

RESUMO

Spectral-beam-combining (SBC) systems utilizing multiple volume Bragg gratings must be carefully analyzed to maximize channel density and efficiency, and thus output radiance. This analysis grows increasingly difficult as the number of channels in the system increases, and heuristic optimization techniques are useful tools for exploring the limits of these systems. We explore three classes of multigrating SBC systems: cascaded, where each grating adds a new channel to the system in sequence; sandwiched, where several individual gratings are placed together and all channels enter the system at the same facet; and multiplexed, where all of the gratings occupy the same holographic optical element (HOE). Loss mechanisms differ among these three basic classes, and our optimization algorithm shows that the highest channel density for a given minimum efficiency and fixed operating bandwidth is achieved for a cascaded grating system. The multiplexed grating system exhibits the lowest channel density under the same constraints but has the distinct advantage of being realized by a single HOE. For a particular application, one must weigh channel density and efficiency versus system complexity when choosing among these basic classes of SBC systems. Additionally, one may need to consider the effects of finite-width input beams. As input beam radius is reduced, angular clipping effects begin to dominate over spectral interference and crosstalk effects, limiting all three classes of SBC systems in a similar manner.

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