Publications by authors named "Lopez N"

The theoretical study of catalysis would substantialy benefit from the use of atomistic simulations that can provide information beyond mean-field approaches. To date, the nanoscale understanding of surface reactions has been only qualitatively achieved by means of kinetic Monte Carlo coupled to density functional theory, KMC-DFT. Here, we examine a widely employed model for oxygen interaction with the RuO(110) surface, a highly anisotropic system.

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Gold-palladium (AuPd) nanoparticles have shown significantly enhanced activity relative to monometallic Au and Pd catalysts. Knowledge of composition and metal domain distributions is crucial to understanding activity and selectivity, but these parameters are difficult to ascertain in catalytic experiments that have primarily been devoted to equimolar nanoparticles. Here, we report AuPd nanoparticles of varying Au:Pd molar ratios that were prepared by a seed growth method.

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Objectives: To evaluate the 5 year effects of an intensive intervention versus the standard-of-care intervention on cardiovascular risk factors in HIV-infected patients on antiretroviral therapy (ART).

Methods: This was a longitudinal study including virologically suppressed patients with at least two cardiovascular risk factors or a Framingham risk score ≥10%. Intensive and standard-of-care interventions aimed for low-density lipoprotein cholesterol (LDL-C) <100 and <130 mg/dL, respectively, by using lipid-lowering drugs.

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Through a combination of three needs-based public programs--Medicaid, the Children's Health Insurance Program, and tax credits for purchasing private plans in the new marketplaces--the Affordable Care Act can potentially ensure continuous coverage for many low- and moderate-income Americans. At the same time, half of individuals with incomes at less than twice the poverty level will experience a form of "churning" in their coverage; as changes occur in their life or work circumstances, they will need to switch among these three coverage sources. For many, churning will entail not only changes in covered benefits and cost-sharing, but also in care, owing to differences in provider networks.

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We have studied by means of density functional theory including dispersion contributions, the interaction of small chain alcohols with up to four carbons and three hydroxyl groups on the TiO2(110) rutile surface with different reduction degrees. Adsorption takes place through an acid-base interaction that can lead to both molecular and dissociated species. The latter are energetically preferred.

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Rutile TiO2 is a heavily investigated oxide with, to date, scarce applications in industrial catalysis. The inactivity of this material in oxidations has been related to its inability to dissociate molecular oxygen. Herein we show how rutile catalyzes the oxidation of HBr to Br2 through defect states that are introduced during the reaction.

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Pseudomonas extremaustralis produces mainly polyhydroxybutyrate (PHB), a short chain length polyhydroxyalkanoate (sclPHA) infrequently found in Pseudomonas species. Previous studies with this strain demonstrated that PHB genes are located in a genomic island. In this work, the analysis of the genome of P.

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Little is known about how social media are used in cancer care. We conducted a systematic review of the use and taxonomy of social media in cancer-related studies, in PubMed, Web of Knowledge, CINAHL, and Google Scholar. We located 1350 articles published through October 2013; 69 met study inclusion criteria.

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We investigated which factors govern the critical steps of cation exchange in metal-organic frameworks by studying the effect of various solvents on the insertion of Ni(2+) into MOF-5 and Co(2+) into MFU-4l. After plotting the extent of cation insertion versus different solvent parameters, trends emerge that offer insight into the exchange processes for both systems. This approach establishes a method for understanding critical aspects of cation exchange in different MOFs and other materials.

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A peroxide dianion (O2(2-)) can be isolated within the cavity of hexacarboxamide cryptand, [(O2)⊂mBDCA-5t-H6](2-), stabilized by hydrogen bonding but otherwise free of proton or metal-ion association. This feature has allowed the electron-transfer (ET) kinetics of isolated peroxide to be examined chemically and electrochemically. The ET of [(O2)⊂mBDCA-5t-H6](2-) with a series of seven quinones, with reduction potentials spanning 1 V, has been examined by stopped-flow spectroscopy.

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Site modification and isolation through selective poisoning comprise an effective strategy to enhance the selectivity of palladium catalysts in the partial hydrogenation of triple bonds in acetylenic compounds. The recent emergence of supported hybrid materials matching the stereo- and chemoselectivity of the classical Lindlar catalyst holds promise to revolutionize palladium-catalyzed hydrogenations, and will benefit from an in-depth understanding of these new materials. In this work, we compare the performance of bare, lead-poisoned, and ligand-modified palladium catalysts in the hydrogenation of diverse alkynes.

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Single-incision laparoscopic surgery (SILS) is gaining popularity for a wide variety of surgical operations and capitalizes on the benefits of traditional laparoscopic surgery without incurring multiple incision sites. Traditionally, SILS is performed by a midline periumbilical approach. However, such a minimally invasive approach may be utilized in patients who already have an abdominal incision.

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Unlabelled: The arenavirus nucleoprotein (NP) is the main protein component of viral nucleocapsids and is strictly required for viral genome replication mediated by the L polymerase. Homo-oligomerization of NP is presumed to play an important role in nucleocapsid assembly, albeit the underlying mechanism and the relevance of NP-NP interaction in nucleocapsid activity are still poorly understood. Here, we evaluate the contribution of the New World Tacaribe virus (TCRV) NP self-interaction to nucleocapsid functional activity.

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Background: The purpose of this study was to compare the functional outcomes and quality of life of older and younger patients with similarly treated distal femur fractures.

Methods: We conducted an assessment of 57 patients who sustained distal femur fractures (Orthopaedic Trauma Association Type 33B, C) and underwent surgical treatment at our academic medical center. Patients were divided into 2 groups for analysis: an elderly cohort of patients aged 65 or older and a comparison cohort of patients younger than age of 65.

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Background: To study hormonal changes associated with severe hyperglycemia in critically ill children and the relationship with prognosis and length of stay in intensive care.

Methods: Observational study in twenty-nine critically ill children with severe hyperglycemia defined as 2 blood glucose measurements greater than 180 mg/dL. Severity of illness was assessed using pediatric index of mortality (PIM2), pediatric risk of mortality (PRISM) score, and pediatric logistic organ dysfunction (PELOD) scales.

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A 12-yr-old child, with a history of gestational Erb-Duchenne palsy and, later, musculoskeletal injuries in the left arm caused by a car accident, inspired the design of a customized exoskeleton-like device. Such piece, intended for rehabilitation, has one degree of freedom because the exercise routine involves elbow flexion-extension, which was indicated for the damaged muscular group. The device has two functioning modes, passive and assisted, in which the patient can trigger the movement by a biceps contraction, thus promoting the active role of the user in the rehabilitation process.

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Stressful conditions prevailing in hydrocarbon-contaminated sites influence the diversity, distribution, and activities of microorganisms. Oil bioremediation agents should develop special characteristics to cope with these environments like surfactant production and cellular affinity to hydrocarbons. Additionally, polyhydroxyalkanoate (PHA) accumulation was proven to improve tolerance to stressful conditions.

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An important challenge in the artificial fixation of N2 is to find atom efficient transformations that yield value-added products. Here we explore the coordination complex mediated conversion of ubiquitous species, CO and N2, into isocyanate. We have conceptually split the process into three steps: (1) the six-electron splitting of dinitrogen into terminal metal nitrido ligands, (2) the reduction of the complex by two electrons with CO to form an isocyanate linkage, and (3) the one electron reduction of the metal isocyanate complex to regenerate the starting metal complex and release the product.

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This paper presents an interface that uses two different sensing techniques and combines both results through a fusion process to obtain the minimum-variance estimator of the orientation of the user's head. Sensing techniques of the interface are based on an inertial sensor and artificial vision. The orientation of the user's head is used to steer the navigation of a robotic wheelchair.

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Importance: Interest in minimally invasive distal pancreatectomy (MIDP) has grown in recent years, but currently available data are limited. Greater insight into application patterns and outcomes may be gained from a national database inquiry.

Objectives: To study trends in the use of MIDP and compare the short-term outcomes of MIDP with those of open distal pancreatectomy.

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Microglia and reactive astrocytes accumulate in the spinal cord of rats expressing the Amyotrophic lateral sclerosis (ALS)-linked SOD1 (G93A) mutation. We previously reported that the rapid progression of paralysis in ALS rats is associated with the appearance of proliferative astrocyte-like cells that surround motor neurons. These cells, designated as Aberrant Astrocytes (AbA cells) because of their atypical astrocytic phenotype, exhibit high toxicity to motor neurons.

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Density functional theory simulations including dispersion provide an atomistic description of the role of different compounds in the synthesis of gold-nanorods. Anisotropy is caused by the formation of a complex between the surfactant, bromine, and silver that preferentially adsorbs on some facets of the seeds, blocking them from further growth. In turn, the nanorod structure is driven by the perferential adsorption of the surfactant, which induces the appearance of open {520} lateral facets.

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Neuropathies related to diabetes mellitus can affect 60-70% of patients with diabetes. These can include peripheral polyneuropathies, mononeuropathies, and autonomic neuropathies. Control of glucose, lipids, and hypertension and cessation of smoking can limit onset and progression of these neuropathies.

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