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1.
Nat Mater ; 23(3): 406-413, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38168807

RESUMO

Nanostructured composite electrode materials play a major role in the fields of catalysis and electrochemistry. The self-assembly of metallic nanoparticles on oxide supports via metal exsolution relies on the transport of reducible dopants towards the perovskite surface to provide accessible catalytic centres at the solid-gas interface. At surfaces and interfaces, however, strong electrostatic gradients and space charges typically control the properties of oxides. Here we reveal that the nature of the surface-dopant interaction is the main determining factor for the exsolution kinetics of nickel in SrTi0.9Nb0.05Ni0.05O3-δ. The electrostatic interaction of dopants with surface space charge regions forming upon thermal oxidation results in strong surface passivation, which manifests in a retarded exsolution response. We furthermore demonstrate the controllability of the exsolution response via engineering of the perovskite surface chemistry. Our findings indicate that tailoring the electrostatic gradients at the perovskite surface is an essential step to improve exsolution-type materials in catalytic converters.

2.
Inorg Chem ; 58(15): 10408-10416, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31290653

RESUMO

New heteroleptic rhenium(I) compounds, [fac-Re(I)(CO)3(L)] (e.g., L= tfb-dmpda, (N,N-(4,4,4-trifluorobut-1-en-3-on)-dimethyl propylene diamine)), containing anionic and neutral ligands act as efficient precursors to grow polycrystalline rhenium nitride (ReN) films by their vapor phase deposition at 600 °C. Deposition of ReN films under an external magnetic field showed an orientation effect with preferred growth of crystallites along ⟨100⟩ direction. Rhenium complexes reported here unify high stability and reactivity in a single molecule through a Janus-type coordination around a Re center, constituted by a chelating tridentate ligand and three carbonyl groups imparting a facial geometry. Single-crystal diffraction analysis confirmed the structural integrity of the new rhenium compounds. The rigidity of molecular framework was validated in solution via 1D and 2D NMR spectroscopy, in the gas phase via mass spectrometry, and in the solid-state by thermogravimetric analysis and differential scanning calorimetry studies. The analytical data showed that pre-existent Re-N bonds in [fac-Re(I)(CO)3(L)] facilitated low-temperature formation of crystalline ReN deposits confirmed by grazing angle X-ray diffraction analysis. The surface chemical composition and the uniformity of microstructure were provided by X-ray photoelectron spectroscopy (XPS) and scanning and transmission electron microscopy (SEM/TEM), respectively.

3.
Neurourol Urodyn ; 38(1): 248-253, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30311667

RESUMO

AIMS: This paper presents 4-year follow-up results for patients enrolled in a pivotal study conducted to support an FDA premarket approval application (PMAA). The study evaluated the safety and efficacy of the ProACT Adjustable Continence Therapy for the treatment of post-prostatectomy stress urinary incontinence (SUI). METHODS: The clinical study involved 11 clinical sites and enrolled 160 subjects, all male. A total of 124 subjects met study criteria and 123 were implanted with ProACT. Baseline and outcomes for 68 patients who completed 4-year follow-up visits are reported. Endpoints included 24-h pad weight, Incontinence Quality of Life Questionnaire (I-QOL), UCLA Prostate Cancer Index-Urinary Function (PCI-UF), residual volume, and incidence and severity of device or procedure-related adverse events. RESULTS: Statistically significant improvements during follow-up were observed in 24-h pad weight, for which the mean pre-implant urine loss was 293 g, which was reduced at 4 years to 73 g (P < 0.001). Reductions in pad weight were observed across all levels of pre-implant SUI severity. Significant improvements were also seen in quality of life as measured by the I-QOL (P < 0.001) as well as measures of urinary function and pad use. One procedure-related SAE (retention) was reported among the 68 subjects; the SAE was resolved without clinical meaningful sequalae. CONCLUSIONS: These results confirm the long-term safety and efficacy of this newly FDA-approved therapy, showing significant improvements in both objective and subjective measures of SUI in mild, moderate, and severely incontinent male patients. The implant procedure is minimally invasive, and complications are generally mild and easily resolvable.


Assuntos
Prostatectomia/efeitos adversos , Próteses e Implantes , Incontinência Urinária por Estresse/cirurgia , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Neoplasias da Próstata/cirurgia , Qualidade de Vida , Inquéritos e Questionários , Resultado do Tratamento , Incontinência Urinária por Estresse/etiologia
4.
Neurourol Urodyn ; 37(8): 2854-2859, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30178536

RESUMO

AIMS: This paper presents 18-month follow-up results for patients enrolled in a pivotal study conducted to support an FDA premarket approval application (PMAA). The trial evaluated the safety and efficacy of the ProACT Adjustable Continence Therapy for the treatment of post-prostatectomy stress urinary incontinence (SUI). METHODS: The clinical study involved 11 clinical sites and enrolled 160 subjects. A total of 124 subjects met study criteria and 123 underwent ProACT implantation from July 2005 through June 2007, of whom 98 completed 18-month follow-up. Endpoints included 24-h pad weight, Incontinence Quality of Life Questionnaire (I-QOL), UCLA Prostate Cancer Index-Urinary Function (PCI-UF), residual volume, and device or procedure-related adverse events (AEs). RESULTS: The mean surgical time was 32 min. Statistically significant improvements during follow-up were observed in 24-h pad weight, for which the cohort mean pre-implant urine loss was 399 g, which was reduced at 18 months to 160 g (P < 0.001). Reductions in pad weight were observed across all levels of pre-implant SUI severity. Significant improvements were also seen in quality of life as measured by the I-QOL (P < 0.001) as well as measures of urinary function and pad count. One procedure-related serious adverse event (SAE), retention, was reported among the 124 subjects; the SAE was resolved without clinical meaningful sequalae. CONCLUSIONS: These results demonstrate the safety and efficacy of this newly FDA-approved therapy, showing significant improvements in objective and subjective measures of SUI in mild, moderate, and severely incontinent male patients. The duration of the implant procedure is short, and complications are mild and easily resolvable.


Assuntos
Complicações Pós-Operatórias/cirurgia , Prostatectomia/efeitos adversos , Próteses e Implantes , Incontinência Urinária por Estresse/cirurgia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Neoplasias da Próstata/cirurgia , Qualidade de Vida , Inquéritos e Questionários , Resultado do Tratamento , Incontinência Urinária por Estresse/etiologia
5.
Adv Mater ; 33(4): e2004132, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33263190

RESUMO

The ability to tailor oxide heterointerfaces has led to novel properties in low-dimensional oxide systems. A fundamental understanding of these properties is based on the concept of electronic charge transfer. However, the electronic properties of oxide heterointerfaces crucially depend on their ionic constitution and defect structure: ionic charges contribute to charge transfer and screening at oxide interfaces, triggering a thermodynamic balance of ionic and electronic structures. Quantitative understanding of the electronic and ionic roles regarding charge-transfer phenomena poses a central challenge. Here, the electronic and ionic structure is simultaneously investigated at the prototypical charge-transfer heterointerface, LaAlO3 /SrTiO3 . Applying in situ photoemission spectroscopy under oxygen ambient, ionic and electronic charge transfer is deconvoluted in response to the oxygen atmosphere at elevated temperatures. In this way, both the rich and variable chemistry of complex oxides and the associated electronic properties are equally embraced. The interfacial electron gas is depleted through an ionic rearrangement in the strontium cation sublattice when oxygen is applied, resulting in an inverse and reversible balance between cation vacancies and electrons, while the mobility of ionic species is found to be considerably enhanced as compared to the bulk. Triggered by these ionic phenomena, the electronic transport and magnetic signature of the heterointerface are significantly altered.

6.
Child Youth Serv Rev ; 29(3): 384-362, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18311320

RESUMO

This paper reviews research findings on caretaking-related problems associated with the absence of parents from the home following incarceration. It focuses on the impact of incarceration on the welfare and adjustment of urban African American children and on the assumption of caretaking responsibilities by other caretakers, principally maternal grandmothers. Noting the complex situational difficulties involved and the potential burdens associated with surrogate parenting in general, and with this population in particular, the service-provider implications of this parenting arrangement are considered in this review. Findings indicate that problems associated with incarceration of parents tend to be intergenerational and vary considerably in complexity and severity. To the extent that they impact the children involved, these issues should be addressed in coordinated service delivery focusing on prevention.

7.
J Robot Surg ; 10(3): 285-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27272759

RESUMO

Herein, we describe several steps to improve surgeon autonomy during a Left Robotic-Assisted Laparoscopic Radical Nephrectomy (RALRN), using the Da Vinci Si system. Our kidney cancer program is based on 2 community hospitals. We use the Da Vinci Si system. Access is obtained with the following trocars: Two 8 mm robotic, one 8 mm robotic, bariatric length (arm 3), 15 mm for the assistant and 12 mm for the camera. We use curved monopolar scissors in robotic arm 1, Bipolar Maryland in arm 2, Prograsp Forceps in arm 3, and we alternate throughout the surgery with EndoWrist clip appliers and the vessel sealer. Here, we described three steps and the use of 3 robotic instruments to improve surgeon autonomy. Step 1: the lower pole of the kidney was dissected and this was retracted upwards and laterally. This maneuver was performed using the 3rd robotic arm with the Prograsp Forceps. Step 2: the monopolar scissors was replaced (robotic arm 1) with the robotic EndoWrist clip applier, 10 mm Hem-o-Lok. The renal artery and vein were controlled and transected by the main surgeon. Step 3: the superior, posterolateral dissection and all bleeders were carefully coagulated by the surgeon with the EndoWrist one vessel sealer. We have now performed 15 RALRN following these steps. Our results were: blood loss 300 cc, console time 140 min, operating room time 200 min, anesthesia time 180 min, hospital stay 2.5 days, 1 incisional hernia, pathology: (13) RCC clear cell, (1) chromophobe and (1) papillary type 1. Tumor Stage: (5) T1b, (8) T2a, (2) T2b. We provide a concise, step-by-step technique for radical nephrectomy (RN) using the Da Vinci Si robotic system that may provide more autonomy to the surgeon, while maintaining surgical outcome equivalent to standard laparoscopic RN.


Assuntos
Neoplasias Renais/cirurgia , Laparoscopia/métodos , Nefrectomia/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Idoso , Perda Sanguínea Cirúrgica , Dissecação/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Posicionamento do Paciente , Manejo de Espécimes/métodos
8.
J Trauma Manag Outcomes ; 7(1): 4, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23675931

RESUMO

BACKGROUND: Aim of this study was to evaluate prognosis of severely injured patients. METHODS: All severely injured patients with an Injury Severity Score (ISS) ≥ 50 were identified in a 6-year-period between 2000 and 2005 in German Level 1 Trauma Center Murnau. Data was evaluated from German Trauma Registry and Polytrauma Outcome Chart of the German Society for Trauma Surgery and a personal interview to assess working ability and disability and are presented as average. RESULTS: 88 out of 1435 evaluated patients after severe polytrauma demonstrated an ISS ≥ 50 (6.5%), among them 23% women and 77% men. 66 patients (75%) had an ISS of 50-60, 14 (16%) 61-70, and 8 (9%) ≥ 70. In 27% of patients trauma was caused by motor bike accidents. 3.6 body regions were involved. Patients had to be operated 5.3 times and were treated 23 days in the ICU and stayed 73 days in hospital. Mortality rate was 36% and rate of multi-organ failure 28%. 15% of patients demonstrated severe senso-motoric dysfunction as well as residues of severe head injury. 25% recovered well or at least moderately. 29 out of 56 survivors answered the POLO-chart. A personal interview was performed with 13 patients. The state of health was at least moderate in 72% of patients. In 48% interpersonal problems and in 41% severe pain was observed. In 57% of patients problems with working ability regarding duration, as well as quantitative and qualitative performance were observed. Symptoms of post-traumatic stress disorder were found in 41%. The more distal the lesions were located (foot/ankle) the more functional disability affected daily life. In only 15%, working ability was not impaired. 8 out of 13 interviewed patients demonstrated complete work disability. CONCLUSIONS: Even severely injured patients after multiple trauma have a good prognosis. The ISS is an established tool to assess severity and prognosis of trauma, whereas prediction of clinical outcome cannot be deducted from this score.

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