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1.
J Chem Phys ; 158(22)2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37293960

RESUMEN

We explore the performance of a recently introduced N5-scaling excited-state-specific second order perturbation theory (ESMP2) on the singlet excitations of the Thiel benchmarking set. We find that, without regularization, ESMP2 is quite sensitive to π system size, performing well in molecules with small π systems but poorly in those with larger π systems. With regularization, ESMP2 is far less sensitive to π system size and shows a higher overall accuracy on the Thiel set than CC2, equation of motion-coupled cluster with singles and doubles, CC3, and a wide variety of time-dependent density functional approaches. Unsurprisingly, even regularized ESMP2 is less accurate than multi-reference perturbation theory on this test set, which can, in part, be explained by the set's inclusion of some doubly excited states but none of the strong charge transfer states that often pose challenges for state-averaging. Beyond energetics, we find that the ESMP2 doubles norm offers a relatively low-cost way to test for doubly excited character without the need to define an active space.


Asunto(s)
Citoesqueleto , Movimiento (Física)
2.
J Infect Dis ; 225(11): 1923-1932, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35079784

RESUMEN

BACKGROUND: Additional severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines that are safe and effective as primary vaccines and boosters remain urgently needed to combat the coronavirus disease 2019 (COVID-19) pandemic. We describe safety and durability of immune responses following 2 primary doses and a homologous booster dose of an investigational DNA vaccine (INO-4800) targeting full-length spike antigen. METHODS: Three dosage strengths of INO-4800 (0.5 mg, 1.0 mg, and 2.0 mg) were evaluated in 120 age-stratified healthy adults. Intradermal injection of INO-4800 followed by electroporation at 0 and 4 weeks preceded an optional booster 6-10.5 months after the second dose. RESULTS: INO-4800 appeared well tolerated with no treatment-related serious adverse events. Most adverse events were mild and did not increase in frequency with age and subsequent dosing. A durable antibody response was observed 6 months following the second dose; a homologous booster dose significantly increased immune responses. Cytokine-producing T cells and activated CD8+ T cells with lytic potential were significantly increased in the 2.0-mg dose group. CONCLUSIONS: INO-4800 was well tolerated in a 2-dose primary series and homologous booster in all adults, including elderly participants. These results support further development of INO-4800 for use as primary vaccine and booster. CLINICAL TRIALS REGISTRATION: NCT04336410.


Asunto(s)
COVID-19 , Vacunas de ADN , Adulto , Anciano , Anticuerpos Antivirales , Formación de Anticuerpos , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Inmunogenicidad Vacunal , SARS-CoV-2 , Vacunación/efectos adversos , Vacunas de ADN/efectos adversos
3.
Can Urol Assoc J ; 15(12): E658-E663, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34171213

RESUMEN

INTRODUCTION: This quality improvement study examined if a video-based resource could reduce delayed discharges after robotic prostatectomy while maintaining high levels of patient satisfaction. METHODS: From April 2018 to February 2020, all patients undergoing robotic-assisted radical prostatectomy (RARP) were asked to complete an anonymous survey evaluating their perioperative experience. The quality improvement (QI) intervention started in March 2019 with a series of six educational videos being shown to all patients. The videos were used to supplement postoperative instruction. The discharge times of all patients were obtained from The Ottawa Hospital Data Repositories. A run chart analysis was used to detect change in discharge time (outcome measure). Patient satisfaction (balancing measure) was analyzed using Chi-squared analysis and descriptive statistics. RESULTS: A total of 425 robotic prostatectomies (199 pre-intervention, 226 post-intervention) were available. Analysis of the run chart revealed non-random change favoring earlier discharge in the intervention group (p<0.05), with a pre-intervention late discharge rate of 64% and a post-intervention late discharge rate of 55%. A total of 140 surveys (59 pre-intervention, 81 post-intervention) assessing patient satisfaction were completed, corresponding with a response rate of 29.6% and 35.8%, respectively. Median score on a 10-point scale for overall satisfaction was equal between the intervention and non-intervention groups (9 [interquartile range (IQR 8-10) vs. 10 [IQR 8-10], p=0.92). CONCLUSIONS: Patient satisfaction with care and education was high for all patients and was not negatively impacted by this intervention. Video education tools may be one method to help improve the discharge process following RARP.

4.
EClinicalMedicine ; 31: 100689, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33392485

RESUMEN

BACKGROUND: A vaccine against SARS-CoV-2 is of high urgency. Here the safety and immunogenicity induced by a DNA vaccine (INO-4800) targeting the full length spike antigen of SARS-CoV-2 are described. METHODS: INO-4800 was evaluated in two groups of 20 participants, receiving either 1.0 mg or 2.0 mg of vaccine intradermally followed by CELLECTRA® EP at 0 and 4 weeks. Thirty-nine subjects completed both doses; one subject in the 2.0 mg group discontinued trial participation prior to receiving the second dose. ClinicalTrials.gov identifier: NCT04336410. FINDINGS: The median age was 34.5, 55% (22/40) were men and 82.5% (33/40) white. Through week 8, only 6 related Grade 1 adverse events in 5 subjects were observed. None of these increased in frequency with the second administration. No serious adverse events were reported. All 38 subjects evaluable for immunogenicity had cellular and/or humoral immune responses following the second dose of INO-4800. By week 6, 95% (36/38) of the participants seroconverted based on their responses by generating binding (ELISA) and/or neutralizing antibodies (PRNT IC50), with responder geometric mean binding antibody titers of 655.5 [95% CI (255.6, 1681.0)] and 994.2 [95% CI (395.3, 2500.3)] in the 1.0 mg and 2.0 mg groups, respectively. For neutralizing antibody, 78% (14/18) and 84% (16/19) generated a response with corresponding geometric mean titers of 102.3 [95% CI (37.4, 280.3)] and 63.5 [95% CI (39.6, 101.8)], in the respective groups. By week 8, 74% (14/19) and 100% (19/19) of subjects generated T cell responses by IFN-É£ ELISpot assay with the median SFU per 106 PBMC of 46 [95% CI (21.1, 142.2)] and 71 [95% CI (32.2, 194.4)] in the 1.0 mg and 2.0 mg groups, respectively. Flow cytometry demonstrated a T cell response, dominated by CD8+ T cells co-producing IFN-É£ and TNF-α, without increase in IL-4. INTERPRETATION: INO-4800 demonstrated excellent safety and tolerability and was immunogenic in 100% (38/38) of the vaccinated subjects by eliciting either or both humoral or cellular immune responses. FUNDING: Coalition for Epidemic Preparedness Innovations (CEPI).

5.
J Chem Theory Comput ; 16(10): 6132-6141, 2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-32816474

RESUMEN

We show that by working in a basis similar to that of the natural transition orbitals and using a modified zeroth-order Hamiltonian, the cost of a recently introduced perturbative correction to excited-state mean field theory can be reduced from seventh to fifth order in the system size. The (occupied)2(virtual)3 asymptotic scaling matches that of ground-state second-order Møller-Plesset theory but with a significantly higher prefactor because the bottleneck is iterative: it appears in the Krylov-subspace-based solution of the linear equation that yields the first-order wave function. Here, we discuss the details of the modified zeroth-order Hamiltonian we use to reduce the cost and the automatic code generation process we used to derive and verify the cost scaling of the different terms. Overall, we find that our modifications have little impact on the method's accuracy, which remains competitive with singles and doubles equation-of-motion coupled cluster.

6.
J Chem Theory Comput ; 16(3): 1526-1540, 2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32017562

RESUMEN

We present a generalization of the variational principle that is compatible with any Hamiltonian eigenstate that can be specified uniquely by a list of properties. This variational principle appears to be compatible with a wide range of electronic structure methods, including mean field theory, density functional theory, multireference theory, and quantum Monte Carlo. Like the standard variational principle, this generalized variational principle amounts to the optimization of a nonlinear function that, in the limit of an arbitrarily flexible wave function, has the desired Hamiltonian eigenstate as its global minimum. Unlike the standard variational principle, it can target excited states and select individual states in cases of degeneracy or near-degeneracy. As an initial demonstration of how this approach can be useful in practice, we employ it to improve the optimization efficiency of excited state mean field theory by an order of magnitude. With this improved optimization, we are able to demonstrate that the accuracy of the corresponding second-order perturbation theory rivals that of singles-and-doubles equation-of-motion coupled cluster in a substantially broader set of molecules than could be explored by our previous optimization methodology.

7.
J Chem Theory Comput ; 15(9): 4790-4803, 2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31393725

RESUMEN

We present a method for finding individual excited states' energy stationary points in complete active space self-consistent field theory that is compatible with standard optimization methods and highly effective at overcoming difficulties due to root flipping and near-degeneracies. Inspired by both the maximum overlap method and recent progress in excited-state variational principles, our approach combines these ideas in order to track individual excited states throughout the orbital optimization process. In a series of tests involving root flipping, near-degeneracies, charge transfers, and double excitations, we show that this approach is more effective for state-specific optimization than either the naive selection of roots on the basis of energy ordering or a more direct generalization of the maximum overlap method. We provide evidence that this state-specific approach improves the performance of complete active space perturbation theory for vertical excitation energies. Furthermore, we find that the state-specific optimization can help avoid state-averaging-induced discontinuities on potential energy surfaces. With a simple implementation, a low cost, and compatibility with large active space methods, the approach is designed to be useful in a wide range of excited-state investigations.

8.
J Chem Phys ; 149(8): 081101, 2018 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-30193500

RESUMEN

We present a mean field theory for excited states that is broadly analogous to ground state Hartree-Fock theory. Like Hartree-Fock, our approach is deterministic, state-specific, applies a variational principle to a minimally correlated ansatz, produces energy stationary points, relaxes the orbital basis, has a Fock-build cost-scaling, and can serve as the foundation for correlation methods such as perturbation theory and coupled cluster theory. To emphasize this last point, we pair our mean field approach with an excited state analog of second order Møller-Plesset theory and demonstrate that in water, formaldehyde, neon, and stretched lithium fluoride, the resulting accuracy far exceeds that of configuration interaction singles and rivals that of equation of motion coupled cluster.

10.
J Phys Condens Matter ; 30(19): 195901, 2018 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-29582782

RESUMEN

QMCPACK is an open source quantum Monte Carlo package for ab initio electronic structure calculations. It supports calculations of metallic and insulating solids, molecules, atoms, and some model Hamiltonians. Implemented real space quantum Monte Carlo algorithms include variational, diffusion, and reptation Monte Carlo. QMCPACK uses Slater-Jastrow type trial wavefunctions in conjunction with a sophisticated optimizer capable of optimizing tens of thousands of parameters. The orbital space auxiliary-field quantum Monte Carlo method is also implemented, enabling cross validation between different highly accurate methods. The code is specifically optimized for calculations with large numbers of electrons on the latest high performance computing architectures, including multicore central processing unit and graphical processing unit systems. We detail the program's capabilities, outline its structure, and give examples of its use in current research calculations. The package is available at http://qmcpack.org.

11.
J Chem Theory Comput ; 13(12): 6078-6088, 2017 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-29140699

RESUMEN

We demonstrate that a broad class of excited state variational principles is not size consistent. In light of this difficulty, we develop and test an approach to excited state optimization that transforms between variational principles to achieve state selectivity, size consistency, and compatibility with quantum Monte Carlo. To complement our formal analysis, we provide numerical examples that confirm these properties and demonstrate how they contribute to a more black box approach to excited states in quantum Monte Carlo.

12.
J Nurse Pract ; 13(6): e269-e272, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28993721

RESUMEN

The purpose of this pilot was to implement an innovative group care model, "Team Clinic", for adolescents with type 1 diabetes and assess patient and provider perspectives. Ninety-one intervention patients and 87 controls were enrolled. Ninety-six percent of intervention adolescents endorsed increased support and perceived connecting with peers as important. The medical providers and staff also provided positive feedback stating Team Clinic allowed more creativity in education and higher quality of care. Team Clinic may be a promising model to engage adolescents and incorporate education and support into clinic visits in a format valued by patients and providers.

13.
Crit Care Nurs Clin North Am ; 28(4): 425-435, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28236390

RESUMEN

Critical care nurses constitute front-line care provision for patients in the intensive care unit (ICU). Hypoxemic respiratory compromise/failure is a primary reason that patients require ICU admission and mechanical ventilation. Critical care nurses must possess advanced knowledge, skill, and judgment when caring for these patients to ensure that interventions aimed at optimizing oxygenation are both effective and safe. This article discusses fundamental aspects of respiratory physiology and clinical indices used to describe oxygenation status. Key nursing interventions including patient assessment, positioning, pharmacology, and managing hemodynamic parameters are discussed, emphasizing their effects toward mitigating ventilation-perfusion mismatch and optimizing oxygenation.


Asunto(s)
Enfermería de Cuidados Críticos/normas , Oxígeno/metabolismo , Respiración Artificial/enfermería , Síndrome de Dificultad Respiratoria/enfermería , Insuficiencia Respiratoria/enfermería , Hemodinámica/fisiología , Humanos , Unidades de Cuidados Intensivos , Evaluación en Enfermería , Posicionamiento del Paciente
14.
ANS Adv Nurs Sci ; 38(3): E17-37, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26061972

RESUMEN

Increasing numbers of patients living with obesity (PLWO) are admitted to the intensive care unit (ICU). The goal of this qualitative study was to examine the experiences of ICU nurses who work with PLWO using the Othering framework developed by Canales in 2010. The first theme describes how PLWO become "Others" in the ICU. The second theme focuses on exclusionary Othering and how it manifests itself in the way PLWO are cared for and viewed. The third theme sheds light on inclusionary Othering in the form of strategies that are used by nurses to engage with PLWO. The last theme takes a closer look at the ICU environment and how resources impact the experiences of nurses working with PLWO.


Asunto(s)
Actitud del Personal de Salud , Enfermería de Cuidados Críticos/métodos , Empatía , Personal de Enfermería en Hospital/psicología , Obesidad/enfermería , Adulto , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Relaciones Enfermero-Paciente , Investigación Metodológica en Enfermería , Ontario , Investigación Cualitativa
16.
Tuberculosis (Edinb) ; 94(2): 178-82, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24360811

RESUMEN

The ultimate goal of vaccine development is licensure of a safe and efficacious product that has a well-defined manufacturing process resulting in a high quality product. In general, clinical development and regulatory approval occurs in a linear, sequential manner: Phase 1 - safety, immunogenicity; Phase 2 - immunogenicity, safety, dose ranging and preliminary efficacy; Phase 3 - definitive efficacy, safety, lot consistency; and, following regulatory approval, Phase 4 - post-marketing safety and effectiveness. For candidate TB vaccines, where correlates of protection are not yet identified, phase 2 and 3 efficacy of disease prevention trials are, by necessity, very large. Each trial would span 2-5 years, with full licensure expected only after 1 or even 2 decades of development. Given the urgent unmet need for a new TB vaccine, a satellite discussion was held at the International African Vaccinology Conference in Cape Town, South Africa in November 2012, to explore the possibility of expediting licensure by use of an "adaptive licensure" process, based on a risk/benefit assessment that is specific to regional needs informed by epidemiology. This may be appropriate for diseases such as TB, where high rates of morbidity, mortality, particularly in high disease burden countries, impose an urgent need for disease prevention. The discussion focused on two contexts: licensure within the South African regulatory environment - a high burden country where TB vaccine efficacy trials are on-going, and licensure by the United States FDA --a well-resourced regulatory agency where approval could facilitate global licensure of a novel TB vaccine.


Asunto(s)
Aprobación de Drogas/organización & administración , Diseño de Fármacos , Vacunas contra la Tuberculosis , Femenino , Guías como Asunto , Humanos , Concesión de Licencias , Masculino , Sudáfrica
17.
Lancet ; 381(9871): 1021-8, 2013 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-23391465

RESUMEN

BACKGROUND: BCG vaccination provides incomplete protection against tuberculosis in infants. A new vaccine, modified Vaccinia Ankara virus expressing antigen 85A (MVA85A), was designed to enhance the protective efficacy of BCG. We aimed to assess safety, immunogenicity, and efficacy of MVA85A against tuberculosis and Mycobacterium tuberculosis infection in infants. METHODS: In our double-blind, randomised, placebo-controlled phase 2b trial, we enrolled healthy infants (aged 4­6 months) without HIV infection who had previously received BCG vaccination. We randomly allocated infants (1:1), according to an independently generated sequence with block sizes of four, to receive one intradermal dose of MVA85A or an equal volume of Candida skin test antigen as placebo at a clinical facility in a rural region near Cape Town, South Africa. We actively followed up infants every 3 months for up to 37 months. The primary study outcome was safety (incidence of adverse and serious adverse events) in all vaccinated participants, but we also assessed efficacy in a protocol-defined group of participants who received at least one dose of allocated vaccine. The primary efficacy endpoint was incident tuberculosis incorporating microbiological, radiological, and clinical criteria, and the secondary efficacy endpoint was M tuberculosis infection according to QuantiFERON TB Gold In-tube conversion (Cellestis, Australia). This trial was registered with the South African National Clinical Trials Register (DOH-27-0109-2654) and with ClinicalTrials.gov on July 31, 2009, number NCT00953927. FINDINGS: Between July 15, 2009, and May 4, 2011, we enrolled 2797 infants (1399 allocated MVA85A and 1398 allocated placebo). Median follow-up in the per-protocol population was 24·6 months (IQR 19·2­28·1), and did not differ between groups. More infants who received MVA85A than controls had at least one local adverse event (1251 [89%] of 1399 MVA85A recipients and 628 [45%] of 1396 controls who received the allocated intervention) but the numbers of infants with systemic adverse events (1120 [80%] and 1059 [76%]) or serious adverse events (257 [18%] and 258 (18%) did not differ between groups. None of the 648 serious adverse events in these 515 infants was related to MVA85A. 32 (2%) of 1399 MVA85A recipients met the primary efficacy endpoint (tuberculosis incidence of 1·15 per 100 person-years [95% CI 0·79 to 1·62]; with conversion in 178 [13%] of 1398 infants [95% CI 11·0 to 14·6]) as did 39 (3%) of 1395 controls (1·39 per 100 person-years [1·00 to 1·91]; with conversion in 171 [12%] of 1394 infants [10·6 to 14·1]). Efficacy against tuberculosis was 17·3% (95% CI −31·9 to 48·2) and against M tuberculosis infection was −3·8% (­28·1 to 15·9). INTERPRETATION: MVA85A was well tolerated and induced modest cell-mediated immune responses. Reasons for the absence of MVA85A efficacy against tuberculosis or M tuberculosis infection in infants need exploration. FUNDING: Aeras, Wellcome Trust, and Oxford-Emergent Tuberculosis Consortium (OETC).


Asunto(s)
Vacuna BCG , Vacunas contra la Tuberculosis/administración & dosificación , Tuberculosis/prevención & control , Vacunas Virales/administración & dosificación , Antígenos Bacterianos/sangre , Antígenos Bacterianos/inmunología , Método Doble Ciego , Femenino , Humanos , Lactante , Inyecciones Intradérmicas , Masculino , Mycobacterium tuberculosis , Resultado del Tratamiento , Prueba de Tuberculina , Tuberculosis/inmunología , Vacunas contra la Tuberculosis/efectos adversos , Vacunas contra la Tuberculosis/inmunología , Vacunas de ADN , Vacunas Virales/efectos adversos , Vacunas Virales/inmunología
18.
Magn Reson Med ; 51(4): 794-8, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15065253

RESUMEN

The cerebral deposition of amyloid beta-peptide, a central event in Alzheimer's disease (AD) pathogenesis, begins several years before the onset of clinical symptoms. Noninvasive detection of AD pathology at this initial stage would facilitate intervention and enhance treatment success. In this study, high-field MRI was used to detect changes in regional brain MR relaxation times in three types of mice: 1). transgenic mice (PS/APP) carrying both mutant genes for amyloid precursor protein (APP) and presenilin (PS), which have high levels and clear accumulation of beta-amyloid in several brain regions, starting from 10 weeks of age; 2). transgenic mice (PS) carrying only a mutant gene for presenilin (PS), which show subtly elevated levels of Abeta-peptide without beta-amyloid deposition; and 3). nontransgenic (NTg) littermates as controls. The transverse relaxation time T(2), an intrinsic MR parameter thought to reflect impaired cell physiology, was significantly reduced in the hippocampus, cingulate, and retrosplenial cortex, but not the corpus callosum, of PS-APP mice compared to NTg. No differences in T(1) values or proton density were detected between any groups of mice. These results indicate that T(2) may be a sensitive marker of abnormalities in this transgenic mouse model of AD.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Encéfalo/patología , Imagen por Resonancia Magnética , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Cuerpo Calloso/patología , Modelos Animales de Enfermedad , Giro del Cíngulo/patología , Hipocampo/patología , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Transgénicos , Mutación/genética , Presenilina-1
19.
Magn Reson Med ; 49(3): 576-80, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12594763

RESUMEN

The goal of this work is to provide regional T(1) and T(2) values at a field strength of 7 T for the normal mouse brain at 6 weeks and 1 year old. A novel segmented snapshot FLASH sequence was used to measure T(1) in the hippocampus, corpus callosum, and the retrosplenial granular (RSG) cortex; T(2) measurements were made in the same regions using a single spin echo sequence repeated at six separate echo times. Both T(1) and T(2) measurements were validated with phantom measurements.


Asunto(s)
Encéfalo/anatomía & histología , Imagen Eco-Planar/métodos , Factores de Edad , Animales , Imagen Eco-Planar/instrumentación , Ratones , Ratones Endogámicos , Fantasmas de Imagen , Protones
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