University College Cork

About: University College Cork is a education organization based out in Cork, Ireland. It is known for research contribution in the topics: Population & Irish. The organization has 12056 authors who have published 28452 publications receiving 958414 citations. The organization is also known as: Coláiste na hOllscoile Corcaigh & National University of Ireland, Cork.

Wind-turbine fault ride-through enhancement

Abstract: Fault ride-through specifications listed in modern transmission and distribution grid codes specify that wind-turbine generators (WTGs) must remain connected to electricity networks at voltage levels well below nominal. Achieving reliable operation at greatly reduced voltage levels is proving problematic. A particular problem regarding power converter-based WTGs is that standard controllers designed for reliable operation around nominal voltage levels will not work as designed during low network voltages that can occur during a fault. A consequence of this is greatly increased converter currents, which may lead to converter failure. This paper presents a nonlinear controller design for a power converter-based WTG that ensures that current levels remain within design limits, even at greatly reduced voltage levels, thus enhancing the WTG's fault ride-through capability.

Mesoporous Titania Nanotubes: Their Preparation and Application as Electrode Materials for Rechargeable Lithium Batteries

Abstract: Rights © 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. This is the pre-peer reviewed version of the following article: (2007), Mesoporous Titania Nanotubes: Their Preparation and Application as Electrode Materials for Rechargeable Lithium Batteries. Adv. Mater., 19: 3016-3020, which has been published in final form at https://onlinelibrary.wiley.com/doi/epdf/10.1002/adma.200602189. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving

Regional hypoxia in glioblastoma multiforme quantified with [18F]fluoromisonidazole positron emission tomography before radiotherapy: correlation with time to progression and survival.

Abstract: Purpose: Hypoxia is associated with resistance to radiotherapy and chemotherapy and activates transcription factors that support cell survival and migration. We measured the volume of hypoxic tumor and the maximum level of hypoxia in glioblastoma multiforme before radiotherapy with [ 18 F]fluoromisonidazole positron emission tomography to assess their impact on time to progression (TTP) or survival. Experimental Design: Twenty-two patients were studied before biopsy or between resection and starting radiotherapy. Each had a 20-minute emission scan 2 hours after i.v. injection of 7 mCi of [ 18 F]fluoromisonidazole. Venous blood samples taken during imaging were used to create tissue to blood concentration ( T/B ) ratios. The volume of tumor with T/B values above 1.2 defined the hypoxic volume (HV). Maximum T/B values ( T/B max ) were determined from the pixel with the highest uptake. Results: Kaplan-Meier plots showed shorter TTP and survival in patients whose tumors contained HVs or tumor T/B max ratios greater than the median ( P ≤ 0.001). In univariate analyses, greater HV or tumor T/B max were associated with shorter TTP or survival ( P T/B max ), magnetic resonance imaging (MRI) T1Gd volume, age, and Karnovsky performance score reached significance only for HV (or T/B max ; P Conclusions: The volume and intensity of hypoxia in glioblastoma multiforme before radiotherapy are strongly associated with poorer TTP and survival. This type of imaging could be integrated into new treatment strategies to target hypoxia more aggressively in glioblastoma multiforme and could be applied to assess the treatment outcomes.

Cerebral near infrared spectroscopy oximetry in extremely preterm infants: phase II randomised clinical trial

Abstract: Objective To determine if it is possible to stabilise the cerebral oxygenation of extremely preterm infants monitored by cerebral near infrared spectroscopy (NIRS) oximetry. Design Phase II randomised, single blinded, parallel clinical trial. Setting Eight tertiary neonatal intensive care units in eight European countries. Participants 166 extremely preterm infants born before 28 weeks of gestation: 86 were randomised to cerebral NIRS monitoring and 80 to blinded NIRS monitoring. The only exclusion criterion was a decision not to provide life support. Interventions Monitoring of cerebral oxygenation using NIRS in combination with a dedicated treatment guideline during the first 72 hours of life (experimental) compared with blinded NIRS oxygenation monitoring with standard care (control). Main outcome measures The primary outcome measure was the time spent outside the target range of 55-85% for cerebral oxygenation multiplied by the mean absolute deviation, expressed in %hours (burden of hypoxia and hyperoxia). One hour with an oxygenation of 50% gives 5%hours of hypoxia. Secondary outcomes were all cause mortality at term equivalent age and a brain injury score assessed by cerebral ultrasonography. Randomisation Allocation sequence 1:1 with block sizes 4 and 6 in random order concealed for the investigators. The allocation was stratified for gestational age ( Blinding Cerebral oxygenation measurements were blinded in the control group. All outcome assessors were blinded to group allocation. Results The 86 infants randomised to the NIRS group had a median burden of hypoxia and hyperoxia of 36.1%hours (interquartile range 9.2-79.5%hours) compared with 81.3 (38.5-181.3) %hours in the control group, a reduction of 58% (95% confidence interval 35% to 73%, P Conclusions Cerebral oxygenation was stabilised in extremely preterm infants using a dedicated treatment guideline in combination with cerebral NIRS monitoring. Trial registration ClinicalTrial.gov NCT01590316.