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Degradation of emerging contaminants: Effect of thermal treatment on nb2o5 as photocatalyst. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2021.113484] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Nonequilibrium charge-density-wave order beyond the thermal limit. Nat Commun 2021; 12:2499. [PMID: 33941788 PMCID: PMC8093280 DOI: 10.1038/s41467-021-22778-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/26/2021] [Indexed: 12/02/2022] Open
Abstract
The interaction of many-body systems with intense light pulses may lead to novel emergent phenomena far from equilibrium. Recent discoveries, such as the optical enhancement of the critical temperature in certain superconductors and the photo-stabilization of hidden phases, have turned this field into an important research frontier. Here, we demonstrate nonthermal charge-density-wave (CDW) order at electronic temperatures far greater than the thermodynamic transition temperature. Using time- and angle-resolved photoemission spectroscopy and time-resolved X-ray diffraction, we investigate the electronic and structural order parameters of an ultrafast photoinduced CDW-to-metal transition. Tracking the dynamical CDW recovery as a function of electronic temperature reveals a behaviour markedly different from equilibrium, which we attribute to the suppression of lattice fluctuations in the transient nonthermal phonon distribution. A complete description of the system's coherent and incoherent order-parameter dynamics is given by a time-dependent Ginzburg-Landau framework, providing access to the transient potential energy surfaces.
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Nucleation and Growth Bottleneck in the Conductivity Recovery Dynamics of Nickelate Ultrathin Films. NANO LETTERS 2020; 20:7422-7428. [PMID: 32902285 DOI: 10.1021/acs.nanolett.0c02828] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We investigate THz conductivity dynamics in NdNiO3 and EuNiO3 ultrathin films (15 unit cells, u.c., ∼5.7 nm thick) following a photoinduced thermal quench into the metallic state and reveal a clear contrast between first- and second-order dynamics. While in EuNiO3 the conductivity recovers exponentially, in NdNiO3 the recovery is nonexponential and slower than a simple thermal model. Crucially, it is consistent with first-order dynamics and well-described by a 2d Avrami model, with supercooling leading to metastable phase coexistence on the nano- to mesoscopic scale. This novel observation is a fundamentally dynamic manifestation of the first-order character of the insulator-to-metal transition, which the nanoscale thickness of our films and their fast cooling rate enable us to detect. The large transients seen in our films are promising for fast electronic (and magnetic) switching applications.
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2D THz spectroscopic investigation of ballistic conduction-band electron dynamics in InSb. OPTICS EXPRESS 2019; 27:10854-10865. [PMID: 31052939 DOI: 10.1364/oe.27.010854] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 03/19/2019] [Indexed: 06/09/2023]
Abstract
Using reflective cross-polarized 2D THz time-domain spectroscopy in the range of 1-12 THz, we follow the trajectory of the out-of-equilibrium electron population in the low-bandgap semiconductor InSb. The 2D THz spectra show a set of distinct features at combinations of the plasma-edge and vibration frequencies. Using finite difference time domain simulations combined with a tight binding model of the band structure, we assign these features to electronic nonlinearities and show that the nonlinear response in the first picoseconds is dominated by coherent ballistic motion of the electrons. We demonstrate that this technique can be used to investigate the landscape of the band curvature near the Γ-point, as illustrated by the observation of anisotropy in the (100)-plane.
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Optically induced transient enhancement of a structural order parameter. EPJ WEB OF CONFERENCES 2019. [DOI: 10.1051/epjconf/201920507001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We photoexcite SrTiO3 and EuTiO3 in their purely soft-mode-driven structurally distorted phase and trace the structural order parameter via ultra-short x-rays. We observe a rapid decay for SrTiO3 and an intriguing transient enhancement for EuTiO3.
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Ultrafast Relaxation Dynamics of the Antiferrodistortive Phase in Ca Doped SrTiO_{3}. PHYSICAL REVIEW LETTERS 2018; 121:055701. [PMID: 30118273 DOI: 10.1103/physrevlett.121.055701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Indexed: 06/08/2023]
Abstract
The ultrafast dynamics of the octahedral rotation in Ca:SrTiO_{3} is studied by time-resolved x-ray diffraction after photoexcitation over the band gap. By monitoring the diffraction intensity of a superlattice reflection that is directly related to the structural order parameter of the soft-mode driven antiferrodistortive phase in Ca:SrTiO_{3}, we observe an ultrafast relaxation on a 0.2 ps timescale of the rotation of the oxygen octahedron, which is found to be independent of the initial temperature despite large changes in the corresponding soft-mode frequency. A further, much smaller reduction on a slower picosecond timescale is attributed to thermal effects. Time-dependent density-functional-theory calculations show that the fast response can be ascribed to an ultrafast displacive modification of the soft-mode potential towards the normal state induced by holes created in the oxygen 2p states.
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Coupling between a Charge Density Wave and Magnetism in an Heusler Material. PHYSICAL REVIEW LETTERS 2017; 119:227207. [PMID: 29286787 DOI: 10.1103/physrevlett.119.227207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Indexed: 06/07/2023]
Abstract
The prototypical magnetic memory shape alloy Ni_{2}MnGa undergoes various phase transitions as a function of the temperature, pressure, and doping. In the low-temperature phases below 260 K, an incommensurate structural modulation occurs along the [110] direction which is thought to arise from the softening of a phonon mode. It is not at present clear how this phenomenon is related, if at all, to the magnetic memory effect. Here we report time-resolved measurements which track both the structural and magnetic components of the phase transition from the modulated cubic phase as it is brought into the high-symmetry phase. The results suggest that the photoinduced demagnetization modifies the Fermi surface in regions that couple strongly to the periodicity of the structural modulation through the nesting vector. The amplitude of the periodic lattice distortion, however, appears to be less affected by the demagnetization.
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Clinical Severity and Rotavirus Vaccination among Children Hospitalized for Acute Gastroenteritis in Belém, Northern Brazil. J Trop Pediatr 2016; 62:276-81. [PMID: 26884442 DOI: 10.1093/tropej/fmv098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
In March 2006, Brazil introduced the monovalent rotavirus (RV) vaccine (Rotarix™) into the public sector. This study assessed the severity of rotavirus gastroenteritis (RVGE) according to the vaccination status among hospitalized children. We identified 1023 RVGE episodes among not vaccinated (n = 252), partially vaccinated (n = 156) and fully vaccinated (n = 615) children. Very severe gastroenteritis (scored ≥ 15) was reported in 16.7, 17.9 and 13.5% of not vaccinated, partially vaccinated and fully vaccinated children, respectively. There was a trend for a shorter duration of RV diarrhoea among vaccinated children than in not vaccinated children (p = 0.07). A protective effect of vaccination was noted when mean duration of symptoms and hospital stay are analysed, comparing unvaccinated, partially vaccinated and fully vaccinated children (p < 0.05). We showed a vaccination dose effect trend, with fully vaccinated children having less-severe RVGE than not vaccinated and partially vaccinated children.
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A case of paraneoplastic syndrome associated rapidly progressing glomerulonephritis in a patient with colon cancer. Indian J Nephrol 2014; 24:404. [PMID: 25484541 PMCID: PMC4244727 DOI: 10.4103/0971-4065.133031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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Quantitative and molecular analysis of noroviruses RNA in blood from children hospitalized for acute gastroenteritis in Belém, Brazil. J Clin Virol 2013; 58:31-5. [DOI: 10.1016/j.jcv.2013.06.043] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 06/14/2013] [Accepted: 06/29/2013] [Indexed: 10/26/2022]
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Anisotropic electronic state via spontaneous phase separation in strained vanadium dioxide films. PHYSICAL REVIEW LETTERS 2013; 111:096602. [PMID: 24033058 DOI: 10.1103/physrevlett.111.096602] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Indexed: 06/02/2023]
Abstract
We resolved the enigma of anisotropic electronic transport in strained vanadium dioxide (VO2) films by inquiring into the role that strain plays in the nanoscale phase separation in the vicinity of the insulator-to-metal transition. The root source of the anisotropy was visualized as the formation of a peculiar unidirectional stripe state which accompanies the phase transition. Furthermore, nanoscale infrared spectroscopy unveils distinct facets of electron-lattice interplay at three different stages of the phase transition. These stages include the initial formation of sparse nonpercolating metallic domains without noticeable involvement of the lattice followed by an electron-lattice coupled anisotropic stripe state close to percolation which ultimately evolves into a nearly isotropic rutile metallic phase. Our results provide a unique mesoscopic perspective for the tunable macroscopic phenomena in strained metal oxide films.
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Trauma Association of Canada (TAC) Annual Scientific Meeting. The Westin Whistler Resort & Spa, Whistler, BC, Thursday, Apr. 11 to Saturday, Apr. 13, 2013Testing the reliability of tools for pediatric trauma teamwork evaluation in a North American high-resource simulation settingThe association of etomidate with mortality in trauma patientsDefinition of isolated hip fractures as an exclusion criterion in trauma centre performance evaluations: a systematic reviewEstimation of acute care hospitalization costs for trauma hospital performance evaluation: a systematic reviewHospital length of stay following admission for traumatic injury in Canada: a multicentre cohort studyPredictors of hospital length of stay following traumatic injury: a multicentre cohort studyInfluence of the heterogeneity in definitions of an isolated hip fracture used as an exclusion criterion in trauma centre performance evaluations: a multicentre cohort studyPediatric trauma, advocacy skills and medical studentsCompliance with the prescribed packed red blood cell, fresh frozen plasma and platelet ratio for the trauma transfusion pathway at a level 1 trauma centreEarly fixed-wing aircraft activation for major trauma in remote areasDevelopment of a national, multi-disciplinary trauma crisis resource management curriculum: results from the pilot courseThe management of blunt hepatic trauma in the age of angioembolization: a single centre experienceEarly predictors of in-hospital mortality in adult trauma patientsThe impact of open tibial fracture on health service utilization in the year preceding and following injuryA systematic review and meta-analysis of the efficacy of red blood cell transfusion in the trauma populationSources of support for paramedics managing work-related stress in a Canadian EMS service responding to multisystem trauma patientsAnalysis of prehospital treatment of pain in the multisystem trauma patient at a community level 2 trauma centreIncreased mortality associated with placement of central lines during trauma resuscitationChronic pain after serious injury — identifying high risk patientsEpidemiology of in-hospital trauma deaths in a Brazilian university teaching hospitalIncreased suicidality following major trauma: a population-based studyDevelopment of a population-wide record linkage system to support trauma researchInduction of hmgb1 by increased gut permeability mediates acute lung injury in a hemorrhagic shock and resuscitation mouse modelPatients who sustain gunshot pelvic fractures are at increased risk for deep abscess formation: aggravated by rectal injuryAre we transfusing more with conservative management of isolated blunt splenic injury? A retrospective studyMotorcycle clothesline injury prevention: Experimental test of a protective deviceA prospective analysis of compliance with a massive transfusion protocol - activation alone is not enoughAn evaluation of diagnostic modalities in penetrating injuries to the cardiac box: Is there a role for routine echocardiography in the setting of negative pericardial FAST?Achievement of pediatric national quality indicators — an institutional report cardProcess mapping trauma care in 2 regional health authorities in British Columbia: a tool to assist trauma sys tem design and evaluationPatient safety checklist for emergency intubation: a systematic reviewA standardized flow sheet improves pediatric trauma documentationMassive transfusion in pediatric trauma: a 5-year retrospective reviewIs more better: Does a more intensive physiotherapy program result in accelerated recovery for trauma patients?Trauma care: not just for surgeons. Initial impact of implementing a dedicated multidisciplinary trauma team on severely injured patientsThe role of postmortem autopsy in modern trauma care: Do we still need them?Prototype cervical spine traction device for reduction stabilization and transport of nondistraction type cervical spine injuriesGoing beyond organ preservation: a 12-year review of the beneficial effects of a nonoperative management algorithm for splenic traumaAssessing the construct validity of a global disability measure in adult trauma registry patientsThe mactrauma TTL assessment tool: developing a novel tool for assessing performance of trauma traineesA quality improvement approach to developing a standardized reporting format of ct findings in blunt splenic injuriesOutcomes in geriatric trauma: what really mattersFresh whole blood is not better than component therapy (FFP:RBC) in hemorrhagic shock: a thromboelastometric study in a small animal modelFactors affecting mortality of chest trauma patients: a prospective studyLong-term pain prevalence and health related quality of life outcomes for patients enrolled in a ketamine versus morphine for prehospital traumatic pain randomized controlled trialDescribing pain following trauma: predictors of persistent pain and pain prevalenceManagement strategies for hemorrhage due to pelvic trauma: a survey of Canadian general surgeonsMajor trauma follow-up clinic: Patient perception of recovery following severe traumaLost opportunities to enhance trauma practice: culture of interprofessional education and sharing among emergency staffPrehospital airway management in major trauma and traumatic brain injury by critical care paramedicsImproving patient selection for angiography and identifying risk of rebleeding after angioembolization in the nonoperative management of high grade splenic injuriesFactors predicting the need for angioembolization in solid organ injuryProthrombin complex concentrates use in traumatic brain injury patients on oral anticoagulants is effective despite underutilizationThe right treatment at the right time in the right place: early results and associations from the introduction of an all-inclusive provincial trauma care systemA multicentre study of patient experiences with acute and postacute injury carePopulation burden of major trauma: Has introduction of an organized trauma system made a difference?Long-term functional and return to work outcomes following blunt major trauma in Victoria, AustraliaSurgical dilemma in major burns victim: heterotopic ossification of the tempromandibular jointWhich radiological modality to choose in a unique penetrating neck injury: a differing opinionThe Advanced Trauma Life Support (ATLS) program in CanadaThe Rural Trauma Team Development Course (RTTDC) in Pakistan: Is there a role?Novel deployment of BC mobile medical unit for coverage of BMX world cup sporting eventIncidence and prevalence of intra-abdominal hypertension and abdominal compartment syndrome in critically ill adults: a systematic review and meta-analysisRisk factors for intra-abdominal hypertension and abdominal compartment syndrome in critically ill or injured adults: a systematic review and meta-analysisA comparison of quality improvement practices at adult and pediatric trauma centresInternational trauma centre survey to evaluate content validity, usability and feasibility of quality indicatorsLong-term functional recovery following decompressive craniectomy for severe traumatic brain injuryMorbidity and mortality associated with free falls from a height among teenage patients: a 5-year review from a level 1 trauma centreA comparison of adverse events between trauma patients and general surgery patients in a level 1 trauma centreProcoagulation, anticoagulation and fibrinolysis in severely bleeding trauma patients: a laboratorial characterization of the early trauma coagulopathyThe use of mobile technology to facilitate surveillance and improve injury outcome in sport and physical activityIntegrated knowledge translation for injury quality improvement: a partnership between researchers and knowledge usersThe impact of a prevention project in trauma with young and their learningIntraosseus vascular access in adult trauma patients: a systematic reviewThematic analysis of patient reported experiences with acute and post-acute injury careAn evaluation of a world health organization trauma care checklist quality improvement pilot programProspective validation of the modified pediatric trauma triage toolThe 16-year evolution of a Canadian level 1 trauma centre: growing up, growing out, and the impact of a booming economyA 20-year review of trauma related literature: What have we done and where are we going?Management of traumatic flail chest: a systematic review of the literatureOperative versus nonoperative management of flail chestEmergency department performance of a clinically indicated and technically successful emergency department thoracotomy and pericardiotomy with minimal equipment in a New Zealand institution without specialized surgical backupBritish Columbia’s mobile medical unit — an emergency health care support resourceRoutine versus ad hoc screening for acute stress: Who would benefit and what are the opportunities for trauma care?A geographical analysis of the Early Development Instrument (EDI) and childhood injuryDevelopment of a pediatric spinal cord injury nursing course“Kids die in driveways” — an injury prevention campaignEpidemiology of traumatic spine injuries in childrenA collaborative approach to reducing injuries in New Brunswick: acute care and injury preventionImpact of changes to a provincial field trauma triage tool in New BrunswickEnsuring quality of field trauma triage in New BrunswickBenefits of a provincial trauma transfer referral system: beyond the numbersThe field trauma triage landscape in New BrunswickImpact of the Rural Trauma Team Development Course (RTTDC) on trauma transfer intervals in a provincial, inclusive trauma systemTrauma and stress: a critical dynamics study of burnout in trauma centre healthcare professionalsUltrasound-guided pediatric forearm fracture reduction with sedation in the emergency departmentBlock first, opiates later? The use of the fascia iliaca block for patients with hip fractures in the emergency department: a systematic reviewRural trauma systems — demographic and survival analysis of remote traumas transferred from northern QuebecSimulation in trauma ultrasound trainingIncidence of clinically significant intra-abdominal injuries in stable blunt trauma patientsWake up: head injury management around the clockDamage control laparotomy for combat casualties in forward surgical facilitiesDetection of soft tissue foreign bodies by nurse practitioner performed ultrasoundAntihypertensive medications and walking devices are associated with falls from standingThe transfer process: perspectives of transferring physiciansDevelopment of a rodent model for the study of abdominal compartment syndromeClinical efficacy of routine repeat head computed tomography in pediatric traumatic brain injuryEarly warning scores (EWS) in trauma: assessing the “effectiveness” of interventions by a rural ground transport service in the interior of British ColumbiaAccuracy of trauma patient transfer documentation in BCPostoperative echocardiogram after penetrating cardiac injuries: a retrospective studyLoss to follow-up in trauma studies comparing operative methods: a systematic reviewWhat matters where and to whom: a survey of experts on the Canadian pediatric trauma systemA quality initiative to enhance pain management for trauma patients: baseline attitudes of practitionersComparison of rotational thromboelastometry (ROTEM) values in massive and nonmassive transfusion patientsMild traumatic brain injury defined by GCS: Is it really mild?The CMAC videolaryngosocpe is superior to the glidescope for the intubation of trauma patients: a prospective analysisInjury patterns and outcome of urban versus suburban major traumaA cost-effective, readily accessible technique for progressive abdominal closureEvolution and impact of the use of pan-CT scan in a tertiary urban trauma centre: a 4-year auditAdditional and repeated CT scan in interfacilities trauma transfers: room for standardizationPediatric trauma in situ simulation facilitates identification and resolution of system issuesHospital code orange plan: there’s an app for thatDiaphragmatic rupture from blunt trauma: an NTDB studyEarly closure of open abdomen using component separation techniqueSurgical fixation versus nonoperative management of flail chest: a meta-analysisIntegration of intraoperative angiography as part of damage control surgery in major traumaMass casualty preparedness of regional trauma systems: recommendations for an evaluative frameworkDiagnostic peritoneal aspirate: An obsolete diagnostic modality?Blunt hollow viscus injury: the frequency and consequences of delayed diagnosis in the era of selective nonoperative managementEnding “double jeopardy:” the diagnostic impact of cardiac ultrasound and chest radiography on operative sequencing in penetrating thoracoabdominal traumaAre trauma patients with hyperfibrinolysis diagnosed by rotem salvageable?The risk of cardiac injury after penetrating thoracic trauma: Which is the better predictor, hemodynamic status or pericardial window?The online Concussion Awareness Training Toolkit for health practitioners (CATT): a new resource for recognizing, treating, and managing concussionThe prevention of concussion and brain injury in child and youth team sportsRandomized controlled trial of an early rehabilitation intervention to improve return to work Rates following road traumaPhone call follow-upPericardiocentesis in trauma: a systematic review. Can J Surg 2013. [DOI: 10.1503/cjs.005813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Saturated ablation in metal hydrides and acceleration of protons and deuterons to keV energies with a soft-x-ray laser. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 83:016403. [PMID: 21405780 DOI: 10.1103/physreve.83.016403] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Revised: 11/25/2010] [Indexed: 05/30/2023]
Abstract
Studies of materials under extreme conditions have relevance to a broad area of research, including planetary physics, fusion research, materials science, and structural biology with x-ray lasers. We study such extreme conditions and experimentally probe the interaction between ultrashort soft x-ray pulses and solid targets (metals and their deuterides) at the FLASH free-electron laser where power densities exceeding 10(17) W/cm(2) were reached. Time-of-flight ion spectrometry and crater analysis were used to characterize the interaction. The results show the onset of saturation in the ablation process at power densities above 10(16) W/cm(2). This effect can be linked to a transiently induced x-ray transparency in the solid by the femtosecond x-ray pulse at high power densities. The measured kinetic energies of protons and deuterons ejected from the surface reach several keV and concur with predictions from plasma-expansion models. Simulations of the interactions were performed with a nonlocal thermodynamic equilibrium code with radiation transfer. These calculations return critical depths similar to the observed crater depths and capture the transient surface transparency at higher power densities.
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DETECTION OF MYOCARDIAL VIABILITY USING DOBUTAMINE STRESS ECHOCARDIOGRAPHY AND MYOCARDIAL CONTRAST AFTER ACUTE MYOCARDIAL INFARCTION. Echocardiography 2004. [DOI: 10.1111/j.0742-2822.2004.t01-16-20040211.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Tacrolimus in induction immunosuppressive treatment in renal transplantation: comparison with cyclosporine. Transplant Proc 2003; 35:1699-700. [PMID: 12962763 DOI: 10.1016/s0041-1345(03)00607-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The aim of the study was to compare the efficacy and safety of induction immunosuppression therapies based on tacrolimus or cyclosporine (CsA) in kidney transplantation. The 240 kidney allograft recipients were divided into two groups: group 1 (n=94) received tacrolimus (.01 mg/kg per day), mycophenolate mofetil (MMF, 2 g/d), and steroids (30 mg/d); and group 2 (n=146) CsA (6 mg/kg per day), MMF (2 g/d), and steroids (30 mg/d). Antilymphocyte serum was administered in cases of acute tubular necrosis. The acute rejection rate was higher among group 2 (30.6%) compared with group 1 patients (12.2%) (P=.001). There were no significant differences between the groups in terms of age, gender, body surface area, serologic virus markers (in donor and recipient), baseline creatinine levels, cause of death, HLA incompatibilities, response to acute tubular necrosis, and number of dialysis sessions. We conclude that both immunosuppressive regimens are effective and safe in kidney transplantation. The survival rates of patients and grafts were similar, but the incidence and degree of acute rejection events were reduced in group 1; this finding may forecast a decreased incidence of chronic renal allograft nephropathy.
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Abstract
The aim of this study was to establish the relationship between vascular lesion chronic allograft nephropathy (CAN) and the presence of cytomegalovirus (CMV) in kidney transplanted patients. We studied 259 consecutive kidney transplant recipients with a minimum follow-up of 6 months; the induction immunosuppressive therapy included a calcineurin inhibitor, mycophenolate mofetil, steroids, and the use of an antilymphocyte serum if the patients developed delayed graft function. CMV early antigen detection (pp65) was performed on a weekly basis between days 30 and 90 post transplantation. Prophylactic treatment was administered in the donor +/recipient-risk group, and preemptive therapy delivered for positive antigenemia namely 3 days of intravenous [IV] gancyclovir [GCV] plus 11 days of oral therapy [in the case of infection], or 14 days of IV GCV [in the case of disease]). An acute kidney allograft rejection episode preceded CMV in 64.3% of the patients, and CMV preceded acute rejection in 35.7% of the cases. We conclude that CMV disease is an independent risk factor for CAN. CMV infection is probably associated with CAN, suggesting that the greater the viral load, the higher the risk of CAN. It may be advisable to perform universal prophylaxis to lower the viral load and CAN.
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Concepts and techniques for planning and implementing a program for renovation of an emergency obstetric care facility. Int J Gynaecol Obstet 2002; 78:263-73; discussion 273. [PMID: 12384276 DOI: 10.1016/s0020-7292(02)00175-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
As emergency obstetric care (EmOC) services are being upgraded, many health planners are considering structural changes to the health facility. Preparing for a renovation is a long process which involves three phases: assessment, planning and implementation. Input from many sources during the course of this process is important. Some design objectives, simple planning techniques and cost considerations are presented. In this paper we discuss some of the critical aspects (based on published literature) in assessing, planning and implementing renovations at an EmOC facility. The actual in-the-field experience of renovations and repairs will be explored in a second paper in this issue.
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Planning and implementing a program of renovations of emergency obstetric care facilities: experiences in Rajasthan, India. Int J Gynaecol Obstet 2002; 78:283-91; discussion 291. [PMID: 12384278 DOI: 10.1016/s0020-7292(02)00191-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Even though many governments and donors are now putting resources into upgrading facilities, the study of the renovation process is one of the most neglected aspects of quality improvement in emergency obstetric care (EmOC). In a previous publication, we discussed basic concepts and simple techniques to assess, plan and implement renovations. Here we focus on actual in-the-field experiences of the renovation process initiated by the health system in Rajasthan, India and the valuable lessons obtained from it. With the advice of the technical members of the Averting Maternal Death and Disability Program (AMDD) and the United Nations Population Fund (UNFPA), the facilities achieved noticeable changes in the physical infrastructure. As a result, the quality of EmOC services improved. We analyze these experiences critically and draw out lessons which may be instructive for future renovation efforts.
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Recommendations for renovating an operating theater at an emergency obstetric care facility. Int J Gynaecol Obstet 2001; 75:287-94; discussion 295. [PMID: 11728491 DOI: 10.1016/s0020-7292(01)00527-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The importance of emergency obstetric care (EmOC) in reducing maternal mortality has focused attention on both the skills of the clinicians to provide high quality care and on the health facilities in which the care is provided. Essential elements of EmOC include the capacity to perform cesarean sections for which an operating theater is needed. This article focuses on renovation of existing operating theaters to meet the necessary standards. While building, adding to, or renovating operating theaters can be expensive, this article emphasizes appropriate materials that are likely to be locally available and relatively inexpensive. The importance of proper maintenance is discussed.
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Longitudinal studies on maternal HIV-1 variants by biological phenotyping, sequence analysis and viral load. Cell Mol Biol (Noisy-le-grand) 1997; 43:1097-114. [PMID: 9449544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In this study, the HIV-1 variant viruses from ten pregnant women and their infants were isolated and characterized longitudinally in order to determine the role that viral envelope (gp120-V3 loop) gene variation and viral tropism play in vertical transmission. Biological phenotyping of each HIV variant was accomplished by growth in MT-2, and macrophages from healthy and non-HIV-infected donors. Genetic characterization of the variants was accomplished by DNA sequence analysis. All the women enrolled in this study received ZDV therapy. Virus was cultured from eight out of ten env V3-PCR positive mothers. HIV-1 isolates were all non-syncitium inducing variants. None of the mothers were found to transmit HIV, as determined by DNA PCR and quantitative co-cultures on their infants which were seronegative for HIV-1 through one year after birth. Viral cultures from infant blood samples were negative and infants were all healthy. However, nested env V3-PCR detected proviral DNA in five out of ten infants. In contrast, conventional gag-PCR was negative in the same five infants. Sequences of the five maternal-infant pairs were different, suggesting unique infant HIV-1 variants. The three highest maternal viral load values corresponded to infants that were env V3-PCR positive. These results suggest that HIV-1 particles are transmitted from ZDV-treated mothers to infants. Infant follow up is recommended to determine if HIV-1 has been inhibited by the immune system of the infants.
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A new efficient approach for the removal of impulse noise from highly corrupted images. IEEE TRANSACTIONS ON IMAGE PROCESSING : A PUBLICATION OF THE IEEE SIGNAL PROCESSING SOCIETY 1996; 5:1012-1025. [PMID: 18285188 DOI: 10.1109/83.503916] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A new framework for removing impulse noise from images is presented in which the nature of the filtering operation is conditioned on a state variable defined as the output of a classifier that operates on the differences between the input pixel and the remaining rank-ordered pixels in a sliding window. As part of this framework, several algorithms are examined, each of which is applicable to fixed and random-valued impulse noise models. First, a simple two-state approach is described in which the algorithm switches between the output of an identity filter and a rank-ordered mean (ROM) filter. The technique achieves an excellent tradeoff between noise suppression and detail preservation with little increase in computational complexity over the simple median filter. For a small additional cost in memory, this simple strategy is easily generalized into a multistate approach using weighted combinations of the identity and ROM filter in which the weighting coefficients can be optimized using image training data. Extensive simulations indicate that these methods perform significantly better in terms of noise suppression and detail preservation than a number of existing nonlinear techniques with as much as 40% impulse noise corruption. Moreover, the method can effectively restore images corrupted with Gaussian noise and mixed Gaussian and impulse noise. Finally, the method is shown to be extremely robust with respect to the training data and the percentage of impulse noise.
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Nerve growth cones isolated from fetal rat brain. IV. Preparation of a membrane subfraction and identification of a membrane glycoprotein expressed on sprouting neurons. J Cell Biol 1985; 101:1977-89. [PMID: 3902858 PMCID: PMC2113944 DOI: 10.1083/jcb.101.5.1977] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
This study describes the preparation of a membrane subfraction from isolated nerve growth cone particles (GCPs) (see Pfenninger, K. H., L. Ellis, M. P. Johnson, L. B. Friedman, and S. Somlo, 1983, Cell, 35:573-584) and the identification in this fraction of a glycoprotein expressed during neurite growth. While approximately 40 major polypeptides are visible in Coomassie Blue-stained SDS polyacrylamide gels of pelleted (partially disrupted) GCPs, a salt-washed membrane fraction prepared from lysed, detergent-permeabilized GCPs contains only 14% of this protein and has an unusually simple polypeptide pattern of seven major bands. Monoclonal antibodies have been generated to GCP membranes isolated from fetal rat brain. These antibodies have been screened differentially with synaptosomes from adult rat brain in order to identify those which recognize antigens expressed selectively during neurite growth. One such antibody (termed 5B4) recognizes a developmentally regulated membrane glycoprotein that is enriched in GCP membranes and expressed in fetal neurons sprouting in vitro. The 5B4 antigen in fetal brain migrates in SDS polyacrylamide gels as a diffuse band of approximately 185-255 kD, is rich in sialic acid, and consists of a small family of isoelectric variants. Freezing-thawing and neuraminidase digestion result in the cleavage of the native antigen into two new species migrating diffusely around 200 and 160 kD. Prolonged neuraminidase digestion sharpens these bands at about 180 and 135 kD, respectively. In the mature brain, antibody 5B4 recognizes a sparse polypeptide migrating at approximately 140 kD. As shown in the following paper (Wallis, I., L. Ellis, K. Suh, and K. H. Pfenninger, 1985, J. Cell Biol., 101:1990-1998), the fetal antigen is specifically associated with regions of neuronal sprouting and, therefore, can be used as a molecular marker of neurite growth.
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Separation of a plasma phospholipid transfer protein from cholesterol ester/phospholipid exchange protein. J Biol Chem 1983; 258:2174-80. [PMID: 6822552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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[Prevalence and periodicity of Bancroft's filaria in diurnal blood from the population of Batey Ocho (Central Barahona), Dominican Republic]. BOLETIN DE LA ASOCIACION MEDICA DE PUERTO RICO 1981; 73:497-502. [PMID: 7039635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Products of delipidation of intestinal chylomicrons with diethyl ether. Atherosclerosis 1980; 36:223-39. [PMID: 7406951 DOI: 10.1016/0021-9150(80)90231-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Manipulation of aggressive behavior in adult DBA/2/Bg and C57BL/10/Bg male mice implanted with testosterone in Silastic tubing. Horm Behav 1977; 8:377-90. [PMID: 560350 DOI: 10.1016/0018-506x(77)90012-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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