Multiwavelength Brillouin-Raman ring-cavity fiber laser with 22-GHz spacing.

We experimentally demonstrate a multi-wave length Brillouin-Raman fiber laser configured in a ring-cavity resonator. Interactions between stimulated Brillouin scattering and Raman amplification in a dispersion compensating fiber, attributed to the generation of 16 output channels at injected Raman pump unit power of 650 mW and Brillouin pump power of 2.0 mW. The first output channel has a peak power of 14.8 mW. By discriminating the even-order Brillouin Stokes signals from circulating in the resonator, the generated output channels were found to have wavelength spacing of ∼22 GHz. The output channels were also found to have average optical signal-to-noise ratio value of 11.7 dB

Flattening effect of four wave mixing on multiwavelength Brillouin-erbium fiber laser.

A multiwavelength Brillouin-erbium fiber laser with enhanced output uniformity is demonstrated and its performance with and without the assistance of four wave mixing (FWM) is compared. The presence of FWM effect is proven by the generation of anti-Stokes wave and higher-order Stokes wave. This scheme is successful in flattening the multiwavelength output. At Brillouin pump wavelength of 1,550 nm, between the first and the last output channel, peak power differences of 4.59 and 8.32 dB are recorded for the scheme with and without the assistance of FWM, respectively. This represents 3.73 dB improvement in the multiwavelength output power uniformity

Seamless tuning range based-on available gain bandwidth in multiwavelength Brillouin fiber laser.

We experimentally demonstrate a simple widely tunable multiwavelength Brillouin/Erbium fiber laser that can be tuned over the entire C-band, thereby greatly improving the tuning range limitation faced by the previous Brillouin-erbium fiber laser architectures. Tuning range of 39 nm from 1527 nm to 1566 nm, which is only limited by the amplification bandwidth of the erbium gain was successfully achieved. At Brillouin pump wavelength of 1550 nm and 1480 nm laser pump and Brillouin pump powers of 130 mW and 2 mW respectively, all the generated output channels have peak power above 0 dBm, with the first output channel having a peak power of 8.52 dBm. The experimental set up that consists of only 4 optical components, is simple, devoid of the complex structure employed previously to enhance the tunability and feedback mechanism normally associated with multiwavelength Brillouin-erbium fiber laser sources. The generated output channels are stable, rigidly separated by 10 GHz (0.08 nm)

Multiwavelength L-band fiber laser with bismuth-oxide EDF and photonic crystal fiber.

A multiwavelength laser comb using a bismuth-based erbium-doped fiber and 50 m photonic crystal fiber is demonstrated in a ring cavity configuration. The fiber laser is solely pumped by a single 1455 nm Raman pump laser to exploit its higher power delivery compared to that of a single-mode laser diode pump. At 264 mW Raman pump power and 1 mW Brillouin pump power, 38 output channels in the L-band have been realized with an optical signal-to-noise ratio above 15 dB and a Stokes line spacing of 0.08 nm. The laser exhibits a tuning range of 12 nm and produces stable Stokes lines across the tuning range between Brillouin pump wavelengths of 1603 nm and 1615 nm

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Clinical and Laboratory Profile of Patients with Epistaxis in Kano, Nigeria: A 10‑year Retrospective Review

Background: Epistaxis is a common cause of otorhinolaryngological clinic visits and admissions into accident and emergency. Severe epistaxis could remarkably alter the hemodynamic milieu of individuals and results into significant morbidity and occasional mortality. Aims: To review the clinical pattern and laboratory test results of individuals treated for epistaxis in a tertiary health care center in northern Nigeria. Methods: This study was a 10-year retrospective review of patients managed for epistaxis in the department of otorhinolaryngology, Aminu Kano teaching hospital, Kano, Nigeria. Case files of patients were retrieved, reviewed, and clinical and laboratory data were extracted. The data were analyzed using Statistical Product and Service Solution version 23. Results: A total of 256 were reviewed with 149 (58.2%) male and 107 (41.8%) female with M: F of 1.4:1. A mean age ± SD of 33.86 ± 20.06 years. Anterior epistaxis was the most prevalent, 126 (49.2%), and majority of the patients presented with severe epistaxis, 75 (29.3%). Most were treated with nasal packing, 93 (36.3%). Majority had abnormal full blood counts and clotting profile results, 158 (61.75) and 104 (40.6%), respectively. There was a significant association between patient's genotype and outcome. Anterior epistaxis and AA genotype were significant positive predictors of outcome. Conclusion: Coagulopathies, anaemia, and hemoglobinopathies are common findings among our patients with epistaxis

A correlation of symptomatology with lung function in patients with allergic rhinosinusitis

Background: Allergic rhinosinusitis is clinically defined as a symptomatic disorder of the nose induced by an IgE‑mediated inflammation following allergen exposure to the membrane lining of the nose. It constitutes a global health problem. Both allergic rhinosinusitis and bronchial asthma are systemic inflammatory conditions that often coexist.Objective: The objectives of the study are to assess the pattern of allergic rhinosinusitis and to correlate nasal symptom score with lung volumes of patients with allergic rhinosinusitis.Methods: This is a prospective study of all the adult patients with clinically diagnosed allergic rhinosinusitis at the study center. Patients’ biodata, symptoms, and signs were obtained using a specially designed form. The symptoms were scored using nasal symptom scoring protocol and the lung volumes determined using spirometry. The data were collated and analyzed using SPSS Version 15 statistical software.Results: There were 300 patients and another 300 nonallergic individuals as control. The most common presenting symptom was nasal congestion (98%), whereas the most common sign was engorged turbinates (91%). The most common trigger of allergic symptoms was dust (72.3%). Spirometric test results were below 90% on average in both sexes and significantly (P < 0.05) below those of the participants in the control group. A large number of patients with abnormal spirometry results have total nasal symptom scores of above 5 (n = 119), whereas few (n = 7) had symptom scores of 5 and below. There was a statistically significant correlation between high total nasal symptom score and abnormal spirometry (χ2 = 72, P = 0.0001).Conclusion: There is a significant correlation between nasal symptom score and reduced lung volumes in patients with allergic rhinosinusitis even in the absence of asthma.Keywords: Allergic rhinosinusitis, correlation, lung functio

Sleep health of healthcare workers in Kano, Nigeria

Background: The relevance of sleep in the life of a human being cannot be overemphasized in terms of physical and mental well-being. Among several factors that can affect the sleep health of an individual occupation have been found to play a prominent role. The literature is still scanty with regard to sleep studies in our environment.Aim: This study aims to assess the sleep health of tertiary healthcare workers in Kano Nigeria and find, if any, its determining or related factors.Material and Methods: This study was cross-sectional questionnairebased survey and involved all consenting staff members of Aminu Kano Teaching Hospital, Kano, Nigeria. The Pittsburgh Sleep Quality Index Questionnaire was used to assess the sleep health of the participants.Results: The participants’ ages ranged from 18 to 65 years and have a mean age of 38.94 ± 8.07 years. There were 119 (74.4%) males and 41 (25.4%) females with a M:F ratio of 3:1 (χ2 = 19.415; P = 0.000). Among the 155 participants who completed all the aspects of the Pittsburgh Sleep Quality Index questionnaires, the overall sleep quality of the study population was found to be significantly poor [good sleepers = 71 (45.8%), poor sleepers = 84 (54.2%), χ2 = 116.4; P = 0.000]. Considering the various occupational groups working in the hospital, poor sleep was commonest among the nurses 35 (42.7%). Furthermore, among the nurses, poor sleep was significantly commoner in those on shift work 27 (77.1%) than those not on shift work 8 (22.9%); χ2 = 36.2; P = 0.000. Multivariate logistic regression analysis showed that age, sex, and duration in service were not significant predictors of poor sleep quality among the participants [odds ratio (OR) = 1.013, 95% confidence interest (CI) = 0.948–1.084, P = 0.698; OR = 0.691, 95% CI = 0.293–1.631, P = 0.399; and OR = 0.993, 95% CI = 0.932–1.058 P = 0.840, respectively).Conclusions: Our study found that a significant proportion of healthcare workers and particularly nurses had poor sleep quality. Also, age, sex, and duration in service were not significant predictors of poor sleep quality among the participants.Keywords: Health personal, Kano Nigeria, occupational health, sleep disorde