Cascaded transformerless DC-DC voltage amplifier with optically isolated switching devices

A very high voltage amplifier is provided in which plural cascaded banks of capacitors are switched by optically isolated control switches so as to be charged in parallel from the preceding stage or capacitor bank and to discharge in series to the succeeding stage or capacitor bank in alternating control cycles. The optically isolated control switches are controlled by a logic controller whose power supply is virtually immune to interference from the very high voltage output of the amplifier by the optical isolation provided by the switches, so that a very high voltage amplification ratio may be attained using many capacitor banks in cascade

Sample positioning in microgravity

Repulsion forces arising from laser beams are provided to produce mild positioning forces on a sample in microgravity vacuum environments. The system of the preferred embodiment positions samples using a plurality of pulsed lasers providing opposing repulsion forces. The lasers are positioned around the periphery of a confinement area and expanded to create a confinement zone. The grouped laser configuration, in coordination with position sensing devices, creates a feedback servo whereby stable position control of a sample within microgravity environment can be achieved

Sample positioning in microgravity

Repulsion forces arising from laser beams are provided to produce mild positioning forces on a sample in microgravity vacuum environments. The system of the preferred embodiment positions samples using a plurality of pulsed lasers providing opposing repulsion forces. The lasers are positioned around the periphery of a confinement area and expanded to create a confinement zone. The grouped laser configuration, in coordination with position sensing devices, creates a feedback servo whereby stable position control of a sample within microgravity environment can be achieved

Onset of Nucleate Boiling and Critical Heat Flux with Boiling Water in Microchannels

This paper focuses on experimental determination of onset of nucleate boiling (ONB) and critical heat flux (CHF) at the microscales, and comparison of these with available correlations. The working fluid is deionised water and microchannel of four different hydraulic diameters: 65, 70, 107 and 125 m, have been tested. Effect of hydraulic diameter (65-125 m), mass flux (60-1410 kg/m2s) and heat flux (0-910 kW/m2) on ONB and CHF has been studied in detail. The heat flux for onset of nucleate boiling increases with hydraulic diameter and mass flux. The critical heat flux tends to increase with a decrease in hydraulic diameter and with increasing mass flux. The effect of surface roughness on CHF has also been tested to a limited extent; no clear change in the CHF value was observed upon changing the surface roughness by an order of magnitude. The empirical correlations tested in this study predict the experimental data to varying extent. These results may help better determine the lower and upper limits of heat flux while designing heat sink for electronic cooling

Triage aux Soins Intensifs : caractéristiques et devenir des patients refusés pour une admission dans une unité de soins intensifs

Ce travail s’intéresse au processus de sélection des patients pour l'unité de soins intensifs (USI), décrit à travers les caractéristiques et le devenir des patients refusés, avec un focus particulier sur les patients jugés « trop bien » pour une admission en USI. L’étude présentée est une étude observationnelle rétrospective monocentrique de tous les patients présentés au médecin intensiviste au cours d'une année et qui ont été soit jugés "trop bien" pour une admission en USI soit admis en USI. L’occurrence d’un événement inattendu a été définie comme la survenue soit d’une admission en USI sans nouvelle cause évidente, soit d’un décès sans limitation de traitement, dans les 7 jours suivant le refus. Les caractéristiques des patients et les facteurs organisationnels ont été analysés en fonction du statut de refus, de l’occurrence d’un évènement et du délai d'admission aux soins intensifs. Parmi les 2219 patients inclus dans l’étude, le taux de refus était de 10,4 %. Le refus était associé aux groupes de diagnostic, aux limitations thérapeutiques, aux séjours dans une unité de soins, à l’horaire nocturne et au taux d'occupation de l’USI. Un événement inattendu a été observé chez 16 (6,9 %) patients refusés, avec une association au temps passé à l'hôpital avant le refus, à un séjour dans une unité de soins, au score SOFA (Sequential Organ Failure Assessment Score) et à l'expertise du médecin. Les retards d’admission en USI ont été associés à la durée de séjour en USI et à l'hôpital. Cette étude démontre que le triage en USI effectué par un médecin intensiviste a permis d’éviter environ une admission sur dix. Le refus a été associé à des facteurs que le médecin intensiviste doit connaitre, tels que des éléments liés au patient et sa pathologie, et à la structure hospitalière. Le processus de triage semble sécuritaire, puisque plus de 90% des patients refusés ont eu une évolution simple. L’occurrence d’une admission ultérieure en USI ou d’un décès parmi la minorité des patients considérés comme trop bien démontre qu’il s’agit d’une population à risque de complication. La prise en considération de certains facteurs individuels, comme le score SOFA, pourrait être une aide supplémentaire pour améliorer le processus de triage.</p

Characteristics, comorbidities, 30-day outcome and in-hospital mortality of patients hospitalised with COVID-19 in a Swiss area – a retrospective cohort study

BACKGROUND Since its first description in December 2019, coronavirus disease 19 (COVID-19) has spread worldwide. There is limited information about presenting characteristics and outcomes of Swiss patients requiring hospitalisation. Furthermore, outcomes 30 days after onset of symptoms and after hospital discharge have not been described. AIMS To describe the clinical characteristics, outcomes 30 days after onset of symptoms and in-hospital mortality of a cohort of patients hospitalised for COVID-19 in a Swiss area. METHODS In this retrospective cohort study, we included all inpatients hospitalised with microbiologically confirmed COVID-19 between 1 March and 12 April 2020 in the public hospital network of a Swiss area (Fribourg). Demographic data, comorbidities and outcomes were recorded. Rate of potential hospital-acquired infection, outcomes 30 days after onset of symptoms and in-hospital mortality are reported. RESULTS One hundred ninety-six patients were included in the study. In our population, 119 (61%) were male and the median age was 70 years. Forty-nine patients (25%) were admitted to the intensive care unit (ICU). The rate of potential hospital-acquired infection was 7%. Overall, 30 days after onset of symptoms 117 patients (60%) had returned home, 23 patients (12%) were in a rehabilitation facility, 18 patients (9%) in a medical ward, 6 patients (3%) in ICU and 32 (16%) patients had died. Among patients who returned home within 30 days, 73 patients (63%) reported persistent symptoms. The overall in-hospital mortality was 17%. CONCLUSION We report the first cohort of Swiss patients hospitalised with COVID-19. Thirty days after onset of the symptoms, 60% had returned home. Among them, 63% still presented symptoms. Studies with longer follow-up are needed to document long-term outcomes in patients hospitalised with COVID-19

Oncology gold standard® practical consensus recommendations for the use of monoclonal antibodies in the management of squamous cell carcinoma of head and neck

We present the 2017 Oncology Gold Standard Practical Consensus Recommendation for use of monoclonal antibodies in the management of advanced squamous cell carcinoma of head neck region

Reduced excitatory neurotransmitter levels in anterior insulae are associated with abdominal pain in irritable bowel syndrome

Irritable bowel syndrome (IBS) is a visceral pain condition with psychological comorbidity. Brain imaging studies in IBS demonstratealtered function in anterior insula (aINS), a key hub for integration of interoceptive, affective, and cognitive processes. However,alterations in aINS excitatory and inhibitory neurotransmission as putative biochemical underpinnings of these functional changesremain elusive. Using quantitative magnetic resonance spectroscopy, we compared women with IBS and healthy women (healthycontrols [HC]) with respect to aINS glutamate 1 glutamine (Glx) and g-aminobutyric acid (GABA1) concentrations and addressedpossible associations with symptoms. Thirty-nine women with IBS and 21 HC underwent quantitative magnetic resonancespectroscopy of bilateral aINS to assess Glx and GABA1 concentrations. Questionnaire data from all participants and prospectivesymptom-diary data from patients were obtained for regression analyses of neurotransmitter concentrations with IBS-related andpsychological parameters. Concentrations of Glx were lower in IBS compared with HC (left aINS P , 0.05, right aINS P , 0.001),whereas no group differences were detected for GABA1concentrations. Lower right-lateralized Glx concentrations in patients weresubstantially predicted by longer pain duration, while less frequent use of adaptive pain‐coping predicted lower Glx in left aINS. Ourfindings provide first evidence for reduced excitatory but unaltered inhibitory neurotransmitter levels in aINS in IBS. The results alsoindicate a functional lateralization of aINS with a stronger involvement of the right hemisphere in perception of abdominal pain and ofthe left aINS in cognitive pain regulation. Our findings suggest that glutaminergic deficiency may play a role in pain processing in IBS.Funding agencies: NIHUnited States Department of Health &amp; Human ServicesNational Institutes of Health (NIH) - USA [P41-RR14075, R01 RR16594-01A1, R01 NS052585-01, K08 MH01573, K01 MH01798]; County Council of Ostergotland; AFA research foundation [DNR. 140407]; Bengt-Ihre f</p