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The recent advent of quantum computing has the potential to overhaul security, communications, and scientific modeling. Superconducting qubits are a leading platform that is advancing noise-tolerant intermediate-scale quantum processors. The implementation requires scaling to large numbers of superconducting qubits, circuit depths, and gate speeds, wherein high-purity RF signal generation and effective cabling transport are desirable. Fiber photonic-enhanced RF signal generation has demonstrated the principle of addressing both signal generation and transport requirements, supporting intermediate qubit numbers and robust packaging efforts; however, fiber-based approaches to RF signal distribution are often bounded by their phase instability. Here, we present a silicon photonic integrated circuit-based version of a photonic-enhanced RF signal generator that demonstrates the requisite stability, as well as a path towards the necessary signal fidelity.
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BACKGROUND: Prolonged delays by patients in making care-seeking decisions remain a significant obstacle to the effective management of acute myocardial infarction. OBJECTIVES: This study aimed to compare the effects of a theory-based cognitive-narrative intervention with those of didactic education over a 24-month period on the participants' attitudes, beliefs, and knowledge regarding acute myocardial infarction, prehospital delay time, and the use of an ambulance. We also explored participants' engagement in the intervention. DESIGN: This study adopted a sequential mixed-methods design comprising a multisite randomized controlled trial and a qualitative study. METHODS: Community-dwelling adult patients with a prior history of acute myocardial infarction in the past year were recruited from four hospitals in Hong Kong. They were randomly assigned to an 8-week theory-based cognitive-narrative intervention that involved a vivid experience of complex decision-making or didactic education. The Acute Coronary Syndrome Response Index questionnaire was administered at baseline (T0) and at 3- (T1), 12- (T2), and 24-month (T3) follow-up time points. Prehospital delay time and the use of an ambulance were evaluated for those participants who had recurrent acute myocardial infarction attacks during the study period. RESULTS: A total of 608 participants were randomly assigned to the theory-based cognitive-narrative intervention group (nâ¯=â¯304) or the didactic education group (nâ¯=â¯304). The intervention group reported greater improvements than the control group in their attitudes (ßâ¯=â¯-1.053, pâ¯=â¯0.002) and beliefs (ßâ¯=â¯-0.686, pâ¯=â¯0.041) regarding acute myocardial infarction and care-seeking at T1. These effects were sustained at T2 [attitudes (ßâ¯=â¯-0.797, pâ¯=â¯0.018); beliefs (ßâ¯=â¯-0.692, pâ¯=â¯0.047)] and T3 [attitudes (ßâ¯=â¯-0.717, pâ¯=â¯0.024); beliefs (ßâ¯=â¯-0.701, pâ¯=â¯0.032)]. Sixty-three participants experienced another acute myocardial infarction event by T2. The median delay times for the intervention and control groups were 3.13â¯h (interquartile range (IQR: 1.15-6.48)) and 4.82â¯h (IQR: 2.23-9.02), respectively. The prehospital delay time was significantly reduced in the intervention group compared with the control group (ßâ¯=â¯-0.07, pâ¯=â¯0.011). The qualitative findings echoed the quantitative findings, as participants indicated that the intervention helped them to understand the variable nature of the disease presentation, which enabled them to recognize the symptoms more readily. CONCLUSION: The novel cognitive-narrative intervention used in this study effectively improved the participants' attitudes and beliefs regarding acute myocardial infarction and reduced the prehospital delay time. TRIAL REGISTRATION: This study was registered with the International Clinical Trials Registry Platform of the World Health Organization (ChiCTR-IIC-17010576) on February 2, 2017; the first participant was recruited on January 11, 2018.
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Síndrome Coronariana Aguda , Infarto do Miocárdio , Adulto , Humanos , Cognição , Conhecimentos, Atitudes e Prática em Saúde , Infarto do Miocárdio/terapia , Aceitação pelo Paciente de Cuidados de SaúdeRESUMO
Importance: Despite decades of educational efforts, patients' prolonged delays in seeking care for symptoms of acute myocardial infarction (AMI) remain the greatest obstacle to successful management of the condition. Objective: To compare the effects of a narrative-based psychoeducational intervention with a didactic educative approach on AMI survivors' intention to seek care for AMI symptoms and on AMI knowledge. Design, Setting, and Participants: A multisite randomized clinical trial recruited community-dwelling patients aged 18 years or older with a history of AMI from 4 hospitals in Hong Kong from January 1, 2018, to January 22, 2021, and followed up participants for 1 year. Interventions: An 8-week narrative-based psychoeducational intervention aimed to create a vivid cognitive experience of complex decision-making and modeled desirable behavioral changes through nurse-led, interactive video sessions using model patients. The control group received 4 nurse-led sessions comprising education about AMI and care seeking delivered using a didactic approach. Main Outcomes and Measures: The primary outcome was the behavioral intention between the 2 groups, reflected by participants' attitudes and beliefs about care seeking for AMI measured using the Acute Coronary Syndrome Response Index-Chinese version. The secondary outcome was AMI knowledge. Results: Six hundred and eight participants (mean [SD] age, 67.2 [8.3] years; 469 [77.1%] male) were randomized to either the narrative-based psychoeducation group (n = 304) or the didactic education group (n = 304). The psychoeducational intervention group reported greater positive changes than the control group in their attitudes (ß = -1.053 [95% CI, -1.714 to -0.391]; P < .001) and beliefs (ß = -0.686 [95% CI, -1.354 to -0.180]; P = .04) toward care seeking at the 3-month follow-up, and the difference was sustained at 12 months for both attitudes (ß = -0.797 [95% CI, -1.477 to -0.117]; P = .02) and beliefs (ß = -0.692 [95% CI, -1.309 to -0.012]; P = .047). There were no significant differences in AMI knowledge between the 2 study groups at the 3-month and 12-month time points. Conclusions and Relevance: The results of this randomized clinical trial found that a novel approach of narrative-based psychoeducation was effective in improving patients' behavioral intention to seek care for AMI symptoms. Longer-term follow-up to evaluate actual care-seeking behavior and clinical outcomes in patients with AMI is warranted to determine the sustained effects of this intervention. Trial Registration: ChiCTR Identifier: ChiCTR-IIC-17010576.
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Infarto do Miocárdio , Humanos , Masculino , Idoso , Feminino , Infarto do Miocárdio/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde , Sobreviventes , Hong KongRESUMO
Older patients are at risk of medication-related problems because of age-related physiological changes and multiple medications taken for multiple co-morbidities. The resultant polypharmacy is frequently associated with inappropriate medication use, which in turn contributes to a range of adverse consequences, including geriatric syndromes (eg, falls, cognitive decline, urinary incontinence) and hospitalisation. In addition, medication non-adherence or discrepancies between the medications prescribed and those actually taken by patients, either intentional or unintentional, are prevalent and can lead to treatment failure. A large proportion of adverse drug events are preventable, and medication errors occur most commonly at the stages of prescribing and subsequent monitoring. There are a number of strategies to address these issues with the aim of ensuring safe prescribing. Furthermore, deprescribing with withdrawal of medications that are inappropriate or of minimal value for patients is increasingly emphasised for optimising medication management. In general, optimisation of medication management should be patient-centred, considering individual circumstances and preferences to determine the treatment goals or priorities for individual patients, and a multidisciplinary approach is recommended.
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Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Conduta do Tratamento Medicamentoso , Polimedicação , Idoso , Idoso de 80 Anos ou mais , Desprescrições , Feminino , Humanos , Prescrição Inadequada , MasculinoRESUMO
PURPOSE: In our center, patients with anorectal malformation, including males with recto-vesical (RV)/recto-bladder neck (RBN)/recto-prostatic urethral (RU) fistulas, and females with recto-vaginal (RV) fistulas have been treated by posterior sagittal anorectoplasty (PSARP) before 2000, and by laparoscopic-assisted anorectal pull-through (LAARP) thereafter. We would like to compare the quality of life (QOL) and long-term defecative function between these two groups of patients 10 years after reconstructive surgery. METHODS: Patients who underwent LAARP between 2001 and 2005 were compared with historical controls treated with PSARP between 1996 and 2000. Degrees of continence were graded by the Krickenbeck classification and Kelly's score. QOL was assessed by Hirschsprung's disease/Anorectal Malformation Quality of Life (HAQL) questionnaire. Results were compared using Chi-square test and t test. RESULTS: There were 14 LAARP and 7 PSARP patients. All attained voluntary bowel movements. Moderate to severe soiling (Krickenbeck Grade 2 and 3) was found in 3/14 LAARP (21.4%) and 1/7 PSARP (14.3%) patients, p = 1.00. Constipation requiring use of laxatives was present in 3/14 LAARP (28.6%) and 1/7 PSARP (14.3%) patients, p = 0.62. Mean Kelly's scores were 3.79 ± 0.98 (LAARP) and 4.71 ± 1.25 (PSARP), p = 0.12. No patient required Malone antegrade continence enema (MACE). The QOL scores based on the HAQL questionnaire were comparable between the two groups in all areas except social functioning, in which the LAARP patients attained a significantly lower mean score (26.4 vs 71.7, p = 0.0001). CONCLUSION: The 10-year outcome between LAARP and PSARP patients in terms of QOL and defecative function is comparable. Impairment in social functioning in these patients is reflected by the self-reported lower level of functioning.
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Canal Anal/cirurgia , Malformações Anorretais/cirurgia , Previsões , Laparoscopia/métodos , Procedimentos de Cirurgia Plástica/métodos , Qualidade de Vida , Reto/cirurgia , Adolescente , Canal Anal/anormalidades , Malformações Anorretais/fisiopatologia , Malformações Anorretais/psicologia , Defecação/fisiologia , Feminino , Seguimentos , Humanos , Masculino , Reto/anormalidades , Inquéritos e Questionários , Resultado do Tratamento , Adulto JovemRESUMO
Reef-based tourism has been developing rapidly in recent decades yet its impacts on reef ecosystems are often overlooked. In Tan-awan, Oslob, Philippines, whale sharks are attracted to the shallow reefs where they are provisioned up to 50 tons y-1 of feed and this phenomenon in turn attracts >300,000 y-1 visitors. Given the intensive provisioning and concentrating tourism activities, we hypothesized that the whale shark tourism-impacted site (IS) will have greater impacts on reef degradation and higher anthropogenic nitrogen pollution level compared to its reference site (RS). Ecological surveys revealed that relative to the RS, the IS had 36% higher relative abundance of Pocillopora and Porites coral over other genera, >2.5-fold lower coral density, and 20% higher macroalgal cover, which we concluded are signs of reef degradation. Also, we conducted stable nitrogen isotope analysis on gorgonian skeletons to trace nitrogen sources at both sites through time. Although an average 1 isotope enrichment found in the IS relative to the RS could indicate anthropogenic nitrogen inputs in the IS, this enrichment was consistent over time and existed before the tourism developed. Despite that, we cautioned against the imminent threat of local eutrophication caused by the continued inputs of nitrogen derived from provisioning and tourism activities. In summary, this study provided the first documentation of the impacts of provisioned whale shark tourism on the local reefs in Tan-awan and established an ecological baseline for future comparisons. Such assessments can offer important information on reef health, coastal development, and tourism management.
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Antozoários , Tubarões , Animais , Recifes de Corais , Ecossistema , FilipinasRESUMO
Syncope is a prevalent health problem among elderly people. It may be neurally mediated or caused by conditions such as orthostatic hypotension, postprandial hypotension, and cardiac disorders. A combination of different aetiologies is not uncommon in the elderly people. Many pathophysiological processes, including age-related physiological changes, co-morbidities, concomitant medication use, and prolonged bedrest, coexist and predispose elderly people to syncope; advanced age and cardiac syncope are associated with increased mortality. Recurrent syncope and its co-morbidities, such as fall-related physical injury, negative psychological impact, and functional decline, may increase the dependency of elderly patients. Furthermore, the overlap between falls and syncope, and the interaction between syncope and frailty complicate management. Available clinical guidelines for the management of syncope that focus on diagnosis, investigation, and treatment are therefore insufficient to address syncope in elderly patients. A comprehensive geriatric approach that considers an individual's functional and cognitive capacities, as well as medical and psychosocial aspects, would be more appropriate.
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Síncope/etiologia , Acidentes por Quedas , Idoso , Fragilidade/complicações , Humanos , Hipotensão Ortostática/complicações , Fatores de Risco , Síncope/terapiaRESUMO
AIM: To define the usefulness of the cross-sectional area (CSA) of the median nerve distal to the carpal tunnel in addition to other established common parameters in the diagnosis of carpal tunnel syndrome (CTS). MATERIALS AND METHODS: Forty-four wrists from 24 symptomatic CTS patients and 32 wrists from 17 asymptomatic volunteers were evaluated by ultrasound. The CSA of the median nerve was measured at four pre-selected levels, i.e., proximal, inlet, outlet, and distal to the carpal tunnel. The flattening ratio, intraneural vascularity, neural fasciculation, and retinacular palmar bowing were also assessed. RESULTS: Significant differences were found between the CTS and control groups for median nerve CSA proximal and distal (p<0.001) to the tunnel as well as retinacular bowing (p<0.001). Using the receiver operating characteristic (ROC) curve, the sensitivity, specificity, and accuracy of using a cut-off of >14 mm2 of CSA proximal and distal to the tunnel were 75%, 87.5%, 86.8% and 63.6%, 100%, 78.9%, respectively. Using either CSA proximal or distal to the tunnel or bowing retinaculum at the outlet >1 mm yielded a sensitivity, specificity, and accuracy of 100%, 84.3% and 93.4%, respectively. CONCLUSION: The median nerve CSA proximal and distal to the carpal tunnel and bowing of the retinaculum at the outlet are helpful in diagnosis of CTS.
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Síndrome do Túnel Carpal/diagnóstico por imagem , Nervo Mediano/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Idoso , Síndrome do Túnel Carpal/fisiopatologia , Feminino , Humanos , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Following a survey on the clinical practice of geriatricians in the management of older people with diabetes and a study of hypoglycaemia in diabetic patients, a round-table discussion with geriatricians and endocrinologists was held in January 2015. Consensus was reached for six domains specifically related to older diabetic people: (1) the considerations when setting an individualised diabetic management; (2) inclusion of geriatric syndrome screening in assessment; (3) glycaemic and blood pressure targets; (4) pharmacotherapy; (5) restrictive diabetic diet; and (6) management goals for nursing home residents.
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Diabetes Mellitus Tipo 2 , Serviços de Saúde para Idosos/normas , Idoso , Hong Kong , Humanos , Sociedades MédicasRESUMO
A compact all-in-line graphene-based distributed feedback Bragg-grating fiber laser (GDFB-FL) with narrow linewidth of hundreds kHz is demonstrated and investigated in this study. Performing as an optical saturable absorber, graphene oscillates the initially kHz linewidth DFB-FL, and generates high-quality passively Q-switched pulses. Pumped with a 980 nm continuous-wave laser, the Q-switched GDFB-FL observes ~1 µs pulse durations, with pulse energies up to ~10 nJ and approaching the transform limit. The peak power is ~600 times higher than the original DFB-FL laser. By optimizing the cavity design and the graphene material, it is predicted that fast Q-switched pulses with more than MHz repetition rates and sub-100 ns pulse durations are achievable. Such transform-limited Q-switched GDFB-FLs with narrow linewidth of sub-MHz have long coherence length, good tunability, stability, compactness and robustness, with potential impact in optical coherent communications, metrology and sensing.
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The development of megalopolises in coastal areas is often linked with severe eutrophication, requiring mitigation of anthropogenic dissolved inorganic nitrogen (DIN) pollution. Yet, identifying the DIN-sources responsible for eutrophication is challenging, hampering mitigation efforts. Here, we utilize the stable nitrogen isotope ratio of endosymbiotic dinoflagellate Symbiodinium spp. (δ15Nsym) associated with the hard coral Porites to trace DIN sources in one of the most urbanized areas of the planet: the Pearl River Delta (PRD). The mean δ15Nsym value found in the coastal waters of Hong Kong (HK), located on the eastern edge of the PRD, (7.4 ± 1.2) was +2.7 higher than at Dongsha Atoll, a reference site unaffected by anthropogenic-DIN (4.7 ± 0.4). The isotopic enrichment suggested a consistent dominance of DIN deriving from local and regional sewage discharges on the eastern edge of HK. Furthermore, the strong depletion of the summer δ15Nsym value (-1.6) observed in southern HK revealed that the Pearl River plume strongly modulates the coastal DIN pool. Our results revealed the value of benthic marine organisms' δ15N for deciphering the complex dynamics of coastal eutrophication and highlighted the pivotal role of transboundary coordination in DIN-pollution mitigation.
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Antozoários , Nitrogênio , Animais , Monitoramento Ambiental , Isótopos de Nitrogênio , RiosRESUMO
The elderly with atrial fibrillation are more prone to stroke. Oral anticoagulants such as warfarin are effective in the prevention of atrial fibrillation-associated stroke and systemic embolism. The CHADS2 or CHA2D2-VASc score and HAS-BLED score were developed to stratify stroke risk associated with atrial fibrillation and bleeding risk in a patient with atrial fibrillation, respectively, to facilitate the decision for and safe use of oral anticoagulant. Nonetheless, the decision for anticoagulation is not straightforward and the elderly with non-valvular atrial fibrillation are often precluded from anticoagulant prescription. Advanced age and disadvantages associated with the elderly such as fall, comorbidities, cognitive impairment, and polypharmacy contribute to the over-concern of physicians about bleeding risk. Various treatment options such as low-intensity warfarin and aspirin plus clopidogrel have been suggested but are inferior to dose-adjusted warfarin. Novel oral anticoagulants with promising efficacy and convenience hold great appeal. Optimal management of underlying medical conditions and modifiable stroke risk factors, together with intervention to improve the safe use of oral anticoagulants, are useful.
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Anticoagulantes/uso terapêutico , Aspirina/uso terapêutico , Fibrilação Atrial/complicações , Acidente Vascular Cerebral/prevenção & controle , Varfarina/uso terapêutico , Idoso , Anticoagulantes/efeitos adversos , Aspirina/efeitos adversos , Comorbidade , Hemorragia/etiologia , Humanos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/etiologia , Varfarina/efeitos adversosAssuntos
Atorvastatina/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Síndrome Metabólica/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Schisandra , Animais , Atorvastatina/sangue , Citocromo P-450 CYP3A/fisiologia , Dieta Hiperlipídica , Masculino , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Fitoterapia , Ratos , Ratos Sprague-DawleyRESUMO
High-Q microresonator is perceived as a promising platform for optical frequency comb generation, via dissipative soliton formation. In order to achieve a higher quality factor and obtain the necessary anomalous dispersion, multi-mode waveguides were previously implemented in Si3N4 microresonators. However, coupling between different transverse mode families in multi-mode waveguides results in periodic disruption of dispersion and quality factor, and consequently causes perturbation to dissipative soliton formation and amplitude modulation to the corresponding spectrum. Careful choice of pump wavelength to avoid the mode crossing region is thus critical in conventional Si3N4 microresonators. Here, we report a novel design of Si3N4 microresonator in which single-mode operation, high quality factor, and anomalous dispersion are attained simultaneously. The novel microresonator is consisted of uniform single-mode waveguides in the semi-circle region, to eliminate bending induced mode coupling, and adiabatically tapered waveguides in the straight region, to avoid excitation of higher order modes. The intrinsic quality factor of the microresonator reaches 1.36 × 10(6) while the group velocity dispersion remains to be anomalous at -50 fs(2)/mm. With this novel microresonator, we demonstrate that broadband phase-locked Kerr frequency combs with flat and smooth spectra can be generated by pumping at any resonances in the optical C-band.
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OBJECTIVE: To investigate the impact of skeletal-related events on survival in patients with metastatic prostate cancer prescribed long-term androgen deprivation therapy. METHODS: This historical cohort study was conducted in two hospitals in Hong Kong. Patients who were diagnosed with metastatic prostate cancer and prescribed androgen deprivation therapy between January 2006 and December 2011 were included. Details of skeletal-related events and mortality were examined. RESULTS: The median follow-up was 28 (range, 1-97) months. Of 119 patients, 52 (43.7%) developed skeletal-related events throughout the study, and the majority received bone irradiation for pain control. The median actuarial overall survival and cancer-specific survival for patients with skeletal-related events were significantly shorter than those without skeletal-related events (23 vs 48 months, P=0.003 and 26 vs 97 months, P<0.001, respectively). Multivariate analysis revealed that the adjusted hazard ratio of presence of skeletal-related events on overall and cancer-specific survival was 2.73 (95% confidence interval, 1.46-5.10; P=0.002) and 3.92 (95% confidence interval, 1.87-8.23; P<0.001), respectively. A prostate-specific antigen nadir of >4 ng/mL was an independent poor prognostic factor for overall and cancer-specific survival after development of skeletal-related events (hazard ratio=10.42; 95% confidence interval, 2.10-51.66 and hazard ratio=10.54; 95% confidence interval, 1.94-57.28, respectively). CONCLUSIONS: Skeletal-related events were common in men with metastatic prostate cancer. This is the first reported study to show that a skeletal-related event is an independent prognostic factor in overall and cancer-specific survival in patients with metastatic prostate cancer prescribed androgen deprivation therapy. A prostate-specific antigen nadir of >4 ng/mL is an independent poor prognostic factor for overall and cancer-specific survival following development of skeletal-related events.
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Antagonistas de Androgênios/uso terapêutico , Neoplasias Ósseas/epidemiologia , Dor/etiologia , Neoplasias da Próstata/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/patologia , Neoplasias Ósseas/secundário , Estudos de Coortes , Seguimentos , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Pulse generation often requires a stabilized cavity and its corresponding mode structure for initial phase-locking. Contrastingly, modeless cavity-free random lasers provide new possibilities for high quantum efficiency lasing that could potentially be widely tunable spectrally and temporally. Pulse generation in random lasers, however, has remained elusive since the discovery of modeless gain lasing. Here we report coherent pulse generation with modeless random lasers based on the unique polarization selectivity and broadband saturable absorption of monolayer graphene. Simultaneous temporal compression of cavity-free pulses are observed with such a polarization modulation, along with a broadly-tunable pulsewidth across two orders of magnitude down to 900 ps, a broadly-tunable repetition rate across three orders of magnitude up to 3 MHz, and a singly-polarized pulse train at 41 dB extinction ratio, about an order of magnitude larger than conventional pulsed fiber lasers. Moreover, our graphene-based pulse formation also demonstrates robust pulse-to-pulse stability and wide-wavelength operation due to the cavity-less feature. Such a graphene-based architecture not only provides a tunable pulsed random laser for fiber-optic sensing, speckle-free imaging, and laser-material processing, but also a new way for the non-random CW fiber lasers to generate widely tunable and singly-polarized pulses.
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Chemotherapy of paediatric haematological malignancies can induce infectious complications of the gastrointestinal tract, with predilection of the ileocaecal region. Common causes of right lower abdominal pain in the febrile patient with neutropaenia include acute appendicitis, typhlitis, ileus and intussusception. In this case report, we describe a teenage boy with acute appendicitis presenting with pneumoperitoneum during his course of chemotherapy. The incidence, aetiology, diagnosis, investigations and management of this uncommon presentation in a common disease are discussed. The controversial topic of the management of acute appendicitis in a febrile patient with neutropaenia is also reviewed and discussed.
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Dor Abdominal/etiologia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Apendicectomia , Apendicite/diagnóstico , Laparoscopia , Laparotomia , Pneumoperitônio/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Dor Abdominal/induzido quimicamente , Antibacterianos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Apendicite/induzido quimicamente , Apendicite/cirurgia , Criança , Diagnóstico Diferencial , Febre , Humanos , Masculino , Meropeném , Tienamicinas/administração & dosagem , Resultado do TratamentoRESUMO
Laser frequency combs are coherent light sources that simultaneously provide pristine frequency spacings for precision metrology and the fundamental basis for ultrafast and attosecond sciences. Recently, nonlinear parametric conversion in high-Q microresonators has been suggested as an alternative platform for optical frequency combs, though almost all in 100 GHz frequencies or more. Here we report a low-phase-noise on-chip Kerr frequency comb with mode spacing compatible with high-speed silicon optoelectronics. The waveguide cross-section of the silicon nitride spiral resonator is designed to possess small and flattened group velocity dispersion, so that the Kerr frequency comb contains a record-high number of 3,600 phase-locked comb lines. We study the single-sideband phase noise as well as the long-term frequency stability and report the lowest phase noise floor achieved to date with -130 dBc/Hz at 1 MHz offset for the 18 GHz Kerr comb oscillator, along with feedback stabilization to achieve frequency Allan deviations of 7 × 10(-11) in 1 s. The reported system is a promising compact platform for achieving self-referenced Kerr frequency combs and also for high-capacity coherent communication architectures.
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The prevalence of vitamin B12 deficiency increases with age and is suggested to be even higher in the elderly living in institutions. This retrospective study evaluated the vitamin B12 and folate status of 1996 institutionalized elderly residents aged over 65years. Among them, 34.9% had vitamin B12 deficiency (serum vitamin B12 <150pmol/L), 11.8% had folate deficiency (serum folate <6.8nmol/L), and 4.9% had both. The majority of vitamin B12 deficient residents (68%) had serum vitamin B12 between 100pmol/L and 149pmol/L. Macrocytosis was found in 24.2% of vitamin B12 deficient residents. A significant increase in macrocytosis was associated with a decrease in serum vitamin B12 below 100pmol/L. Macrocytosis was most common in those with vitamin B12 â¦69pmol/L (50.9%). Overall, vitamin B12 deficiency is common in the institutionalized elderly, however macrocytosis cannot predict deficiency. More liberal testing for vitamin B12 status in the institutionalized elderly may be warranted.