InP based lasers and optical amplifiers with wire-/dot-like active regions

Long wavelength lasers and semiconductor optical amplifiers based on InAs quantum wire-/dot-like active regions were developed on InP substrates dedicated to cover the extended telecommunication wavelength range between 1.4 and 1.65 mu m. In a brief overview different technological approaches will be discussed, while in the main part the current status and recent results of quantum-dash lasers are reported. This includes topics like dash formation and material growth, device performance of lasers and optical amplifiers, static and dynamic properties and fundamental material and device modelin

Self-adaptive high-frequency injection based sensorless control for interior permanent magnet synchronous motor drives \u2020

Abstract: An auto-tuning and self-adaptation procedure for High Frequency Injection (HFI) based position and speed estimation algorithms in Interior Permanent Magnet Synchronous Motor (IPMSM) drives is proposed in this paper. Analytical developments show that, using conventional approaches, the dynamics of the high-frequency tracking loop varies with differential inductances, which in turn depend on the machine operating point. On-line estimation and adaptation of the small signal gain of the loop is proposed here, allowing accurate auto-tuning of the sensorless control scheme which does not rely on a priori knowledge of the machine parameters. On-line adaptation of Phase-Locked Loop (PLL) gains and of the injected voltage magnitude is also possible, leading to important advantages from the performance, loss and acoustic point of view. The theoretical basis of the method has been introduced first and the main concept demonstrated by means of simulations. Implementation has been carried out using the hardware of a commercial industrial drive and two Interior Permanent Magnet Synchronous Motors, namely a prototype and an off-the-shelf machine. Experimental tests demonstrate the feasibility and effectiveness of the proposal

Prolonged treatment of COVID-19 pneumonia with high-flow nasal oxygen: A story of oxygen and resilience

The COVID-19 pandemic has placed significant strain on the oxygen delivery infrastructure of health facilities in resource-constrained health systems. In this case report, we describe a patient with severe COVID-19 pneumonia who was managed with high-flow nasal oxygen for 40 days, with an eventual successful outcome. We discuss the oxygen delivery infrastructure needed to offer this intervention, as well as the psychosocial impact on those undergoing treatment

Clinical significance of fluoroscopic patterns specific for the mitotic spindle in patients with reumatic diseases

Objective: we proposed to determine the clinical significance of anti-NuMA and anti-HsEg5 antibodies in a group of patients affected with rheumatic diseases. Materials and methods: indirect immunofluorescence on HEp-2000 cells at serum dilution of 1:40 was used to examin 26 sera which had previously showed a "mitotic spindle" fluoroscopic pattern type during laboratory routine. Results: 21 sera (80,7%) were identified with NuMA and 5 (19,3%) with HsEg5 patterns alone or associated with other ANA patterns. However only patients with isolated positiveness and that is 15 with NuMA and 4 with HsEg5 stainings were included in this study. Of the NuMA positive patients 5 were affected with arthropathies associated to different forms of thyroiditis, 2 with seronegative arthritis, 2 with antiphospholipid syndrome, 1 with systemic lupus erythematosus (SLE), 1 with rheumatoid arthritis, 1 with sicca syndrome, 1 with undifferentiated connective tissue disease, 1 with Mycoplasma pneumaniae infection and 1 with retinal thrombosis. Of the HsEg5 positive patients 3 were affected with SLE and 1 with seronegative arthritis. Conclusions: NuMA does not prevail in any defined rheumatic disease, while HsEg5 staining were more frequent (75%) in patients affected with SLE all of whom showing high antibody titres

Etude immunocytochimique du développement de la cavité buccale du rat

Flow cytometry and autoradiography are extensively used for the evaluation of the number of cells in S-phase in order to study the proliferative activity within tissues and organs. The recent development of a monoclonal antibody against 5-bromo-2’deoxyuridine (BrdUrd), a nonradioactive thymidine analogue that is incorporated within DNA-synthetizing cells, allows the immunochemical detection of proliferating cells. The use of this antibody allows an immunocytochemical detection of proliferating cells «in situ» on tissue sections.We have applied this new technique for the identification of proliferating cells within the tooth and other organs of rat mouth during development. We believe that this technique, for its precision and simplicity, may be a powerful tool for studying the citokinetic and the differentiation of normal and neoplastic cells within the mouth as well as in other districts of the body.Afin d’évaluer avec précision la prolifération cellulaire dans un tissu ou un organe, on emploie couramment la cytofluorimétrie en flux ainsi que les techniques autoradiographiques, qui permettent d’obtenir des informations sur le nombre de cellules en phase S et par conséquent en prolifération.Récemment, de nouvelles techniques non autoradiographiques ont été mises au point pour l’identification des cellules en prolifération. Ces techniques exploitent l’incorporation de la 5-bromo-2’déoxyuridine (BrdUrd), analogue de la thymidine, dans le DNA en voie de duplication. Ces techniques utilisent un anticorps monoclonal dirigé contre la BrdUrd pour évaluer l’incorporation de cette dernière dans les cellules en phase S. L’emploi de cet anticorps en immunocytochimie permet une facile identification «in situ», sur des coupes de tissu, des cellules en prolifération.Nous avons utilisé ce procédé immunocytochimique pour repérer et identifier les cellules en prolifération dans la dent et dans d’autres organes de la cavité buccale du rat nouveau-né, organes qui sont donc encore en cours de développement. Nous estimons que la technique utilisée dans cette recherche peut constituer, par sa précision et sa simplicité, un instrument valable pour l’étude de la prolifération cellulaire ainsi que de la différenciation cellulaire dans les tissus de la dent et de la cavité buccale, aussi bien dans le domaine de l’organogenèse que dans celui de la pathologie tumorale

Delirium in HIV-infected patients admitted to acute medical wards post universal access to antiretrovirals in South Africa

Background. Delirium is associated with increased mortality and length of hospital stay. Limited data are available from HIV-infected acute hospital admissions in developing countries. We conducted a prospective study of delirium among acute medical admissions in South Africa (SA), a developing country with universal antiretroviral therapy (ART) access and high burdens of tuberculosis (TB) and non-communicable disease.Objectives. To identify the prevalence of, risk factors for and outcomes of delirium in HIV-infected individuals in acute general medical admissions.Methods. Three cohorts of adult acute medical admissions to Groote Schuur and Victoria Wynberg hospitals, Cape Town, SA, were evaluated for prevalent delirium within 24 hours of admission. Reference delirium testing was performed by either consultant physicians or neuropsychologists, using the Confusion Assessment Method.Results. The study included 1 182 acute medical admissions, with 318 (26.9%) HIV-infected. The median (interquartile range) age and CD4 count were 35 (30 - 43) years and 132 (61 - 256) cells/µL, respectively, with 140/318 (44.0%) using ART on admission. The prevalence of delirium was 17.6% (95% confidence interval (CI) 13.7 - 22.1) among HIV-infected patients, and delirium was associated with increased inpatient mortality. In multivariable logistic regression analysis, factors associated with delirium were age ≥55 years (adjusted odds ratio (aOR) 6.95 (95% CI 2.03 - 23.67); p=0.002), and urea ≥15 mmol/L (aOR 4.83 (95% CI 1.7 - 13.44); p=0.003), while ART use reduced risk (p=0.014). A low CD4 count, an unsuppressed viral load and active TB were not predictors of delirium; nor were other previously reported risk factors such as non-opportunistic acute infections or polypharmacy.Conclusions. Delirium is common and is associated with increased mortality in HIV-infected acute medical admissions in endemic settings, despite increased ART use. Older HIV-infected patients with renal dysfunction are at increased risk for inpatient delirium, while those using ART on admission have a reduced risk

Two decades of recipient and donor referrals for heart transplantation to Groote Schuur Hospital, Cape Town, South Africa: A retrospective study

Background. Heart transplantation in South Africa faces numerous challenges related to organ scarcity and unequal access to advanced heart therapy. There is an urgent need to analyse the current transplant referral pathway to optimise equitable access to transplantation. Objectives. To provide an audit of heart transplant referrals to Groote Schuur Hospital, Cape Town, over a 23-year period, focusing on patient demographics, indications for referral, waiting-list dynamics, and transplant referral outcomes. Methods. The study utilised a retrospective patient folder review for the period 1 January 1997 - 31 December 2019 and audited the trends in heart transplant referrals and associated outcomes of the referral at a tertiary academic hospital. Results. A total of 625 recipients were referred for heart transplantation, with the majority being male (n=412; 65.9%), while gender was undocumented for 69 cases (11.0%). The mean age was 38.1 (14.6) years, and 153 (24.5%) were listed for transplant, while 215 (34.4%) were deemed ineligible for listing. Contraindications for listing included social (n=106; 49.3%), medical (n=83; 38.6%) and psychological (n=26; 12.0%) factors, while 134 patients (21.4%) were considered too well. Poor social circumstances (n=38; 39.6%), poor insight (n=28; 29.2%) and poor compliance (n=21; 21.9%) were the most common non-medical reasons for not listing recipients, while obesity (n=30; 31.3%) and smoking (n=23; 24.0%) were notable medical contraindications. Forty-nine patients (7.8%) died during work-up, while 130 (85.0%) of the listed patients received a heart transplant. Of the 429 donor referrals, 139 (32.4%) were accepted for organ procurement. Reasons for declining donors included unsuitability for transplantation (30.3%), lack of capacity (1.8%), and recipient-donor mismatch (66.9%). Conclusion. Three-quarters of the referred patients were deemed unsuitable for heart transplantation for medical and/or social reasons. The ratio of referral to listing has decreased over time. However, once listed, the likelihood of receiving a transplant was high