Publications by authors named "Zavaleta J"

Background: The appearance of the new coronavirus, SARS-CoV-2, in Wuhan - China, in 2019 led to the declaration of a COVID-19 pandemic by the World Health Organization. Peru confirmed its first case on March 6, 2020, prompting a significant change in medical care.

Purpose: Our objective was to determine the impact of the COVID-19 pandemic on cancer treatment in Peru.

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Introduction: The process of teaching and learning mathematics in primary school represents an obstacle for both teachers and pupils. According to the historical-cultural conception of development and education, the way how intellectual concepts are initially introduced may radically affect a student's success in learning. The historical-cultural conception of development, together with activity theory, may serve as the basis for creating a novel methodology for pedagogical work on mathematical concepts with pre-school and school children.

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Autism spectrum disorder (ASD) may be associated with self-imposed dietary restrictions causing nutritional deficiencies, and the anesthesiologist must be aware of their potential clinical implications. Because humans are unable to produce ascorbic acid through endogenous metabolic pathways and children with ASD may avoid vitamin C-containing foods, vitamin C deficiency, or scurvy, may develop in patients scheduled for general anesthesia. Vitamin C deficiency may cause dysfunction in autonomic nervous system processes or pulmonary hypertension resulting in unexpected hemodynamic lability.

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Holometabolous insects have been able to radiate to vast ecological niches as adults through the evolution of adult-specific structures such as wings, antennae and eyes. These structures arise from imaginal discs that show regenerative capacity when damaged. During imaginal disc regeneration, development has been shown to be delayed in the fruit fly , but how conserved the delay-inducing mechanisms are across holometabolous insects has not been assessed.

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Background: Triple-negative breast cancer (TNBC) is a heterogeneous disease with aggressive biology and complex tumor evolution. Our purpose was to identify enrichment patterns of genomic alterations in metastatic triple-negative breast cancer (mTNBC).

Methods: Genomic data were retrieved (mutations and copy number variations) from 550 primary TNBC tumors from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and The Cancer Genome Atlas (TCGA) data sets and 58 mTNBC tumors from "Mutational Profile of Metastatic Breast Cancers" and "The Metastatic Breast Cancer Project.

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Persons with upper limb loss (ULL) experience a high prevalence of falls, with the majority of falls occurring when walking. This issue may be related to altered arm dynamics, which play an important role in proactive mechanisms of locomotor stability. This study investigated effects of ULL and prosthesis use on proactive stability mechanisms, particularly if matching the mass and inertia of the impaired limb to the sound limb would enhance locomotor stability.

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Investigations have begun to connect leg prosthesis mechanical properties and user outcomes to optimize prosthesis designs for maximizing mobility. To date, parametric studies have focused on prosthetic foot properties, but not explicitly longitudinal stiffness that is uniquely modified through shock-absorbing pylons. The linear spring function of these devices might affect work performed on the body center-of-mass during walking.

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Advances in high-throughput technologies and their involvement in the 'omics' of cancer have made possible the identification of hundreds of biomarkers and the development of predictive and prognostic platforms that model the management of cancer from evidence-based medicine to precision medicine. Latin America (LATAM) is a region characterised by fragmented healthcare, high rates of poverty and disparities to access to a basic standard of care not only for cancer but also for other complex diseases. Patients from the public setting cannot afford targeted therapy, the facilities offering genomic platforms are scarce and the use of high-precision radiotherapy is limited to few facilities.

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Although significant resources are being spent researching and fostering the relationship between forests and livelihoods to promote mutually beneficial outcomes, critical gaps in understanding persist. A core reason for such gaps is that researchers, practitioners, and policy makers lack the structured space to interact and collaborate, which is essential for effective, interdisciplinary research, practice, and evaluation. Thus, scientific findings, policy recommendations, and measured outcomes have not always been synthesized into deep, systemic understanding; learning from practice and implementation does not easily find its way into scientific analyses, and science often fails to influence policy.

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Tree plantations play a controversial role in many nations' efforts to balance goals for economic development, ecological conservation, and social justice. This paper seeks to contribute to this debate by analyzing the socioeconomic impact of such plantations. We focus our study on Chile, a country that has experienced extraordinary growth of industrial tree plantations.

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Mars has undergone three main climatic stages throughout its geological history, beginning with a water-rich epoch, followed by a cold and semi-arid era, and transitioning into present-day arid and very cold desert conditions. These global climatic eras also represent three different stages of planetary habitability: an early, potentially habitable stage when the basic requisites for life as we know it were present (liquid water and energy); an intermediate extreme stage, when liquid solutions became scarce or very challenging for life; and the most recent stage during which conditions on the surface have been largely uninhabitable, except perhaps in some isolated niches. Our understanding of the evolution of Mars is now sufficient to assign specific terrestrial environments to each of these periods.

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The Mars Astrobiology Research and Technology Experiment (MARTE) simulated a robotic drilling mission to search for subsurface life on Mars. The drill site was on Peña de Hierro near the headwaters of the Río Tinto river (southwest Spain), on a deposit that includes massive sulfides and their gossanized remains that resemble some iron and sulfur minerals found on Mars. The mission used a fluidless, 10-axis, autonomous coring drill mounted on a simulated lander.

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The coupling of on-column derivatization of small molecules to affinity capillary electrophoresis (ACE) has only been realized during the past 5 yr. In this technique, multiple zones of reagent(s) and ligand or receptor are injected into the capillary column. Upon electrophoresis, zones of sample overlap, yielding product.

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Partial filling multiple injection affinity capillary electrophoresis (PFMIACE) is used to determine binding constants between vancomycin (Van) from Streptomyces orientalis, teicoplanin (Teic) from Actinoplanes teicomyceticus and ristocetin (Rist) from Nocardia lurida to D-Ala-D-Ala terminus peptides and carbonic anhydrase B (CAB, E.C.4.

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This work is an overview of our use of affinity capillary electrophoresis (ACE) to estimate binding constants between D-Ala-D-Ala terminus peptides and the glycopeptides vancomycin (Van) from Streptomyces orientalis, teicoplanin (Teic) from Actinoplanes teicomyceticus, and ristocetin A (Rist) from Nocardia lurida. In these studies, modifications in the ACE technique, including partial-filling ACE (PFACE), flow-through PFACE (FTPFACE), on-column ligand derivatization ACE (OCLDACE), on-column receptor derivatization ACE (OCRDACE), multiple-step ligand injection PFACE (MSLIPFACE), and multiple-injection ACE (MIACE), are described and used to determine binding constants of peptides to antibiotics. The findings described herein demonstrate the advantages of ACE in estimating binding parameters between antibiotics and small peptides over other analytical techniques.

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Multiple-injection affinity capillary electrophoresis (MIACE) was used to determine binding constants (K(b)) between vancomycin, ristocetin, and teicoplanin from Streptomyces orientalis, Nocardia lurida, and Actinoplanes teichomyceticus, respectively, and fluorenylmethoxycarbonyl (Fmoc)-(Gly, Ala, Val, and Phe)-D-Ala-D-Ala peptides. In this technique, separate plugs of sample containing non-interacting standards, peptide one, buffer, and peptide two, were injected into the capillary column and electrophoresed. Peptides migrate through the column at similar electrophoretic mobilities but remain as distinct zones due to the buffer plug between peptides.

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Multiple-injection affinity capillary electrophoresis (MIACE) is used to determine binding constants (Kb) between receptors and ligands using as model systems vancomycin and teicoplanin from Streptomyces orientalis and Actinoplanes teichomyceticus, respectively, and their binding to D-Ala-D-Ala peptides and carbonic anhydrase B (CAB. EC 4.2.

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Ecological community structure is particularly important in vector-borne zoonotic diseases with complex life cycles. Qualitative community model analysis may provide a meaningful alternative to standard population-based models of vector-borne disease. We built on recent mathematical developments in qualitative community modeling coupled with conventional biomathematical models of vector-borne disease transmission, to provide a procedure to analyze risk.

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Background: Anesthesiology departments incur staffing costs that are not covered by revenue because the operating room (OR) time allocation and case scheduling are not done to maximize OR efficiency and because surgical durations are longer than average. The purpose of this article is to demonstrate a method to quantify net anesthesia staffing costs due to longer-than-average surgical durations and evaluate the factors that influence staffing costs.

Methods: Data collected from two anesthesiology departments in academic hospitals for 1 yr included date of surgery, time that patients entered the OR, time that patients exited the OR, surgical service, and the Current Procedural Terminology code for the primary surgical procedure.

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Background: The usefulness of the light microscope has been dramatically enhanced by recent developments in hardware and software. However, current technologies lack the ability to capture and analyze a high-resolution image representing a broad diversity of spectral signatures in a single-pass view. We show that hyperspectral imaging offers such a technology.

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The US Environmental Protection Agency prepares Health Advisories (HA) for drinking water contaminants. The HA provide technical guidance to public health officials or other interested groups on many aspects concerning drinking water contamination. The HA contain information on the chemistry, health effects, analytical methods and treatment technologies for specific contaminants.

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