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1.
Environ Technol ; 44(3): 304-315, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34429035

RESUMEN

Expanded vermiculite was used as an adsorbent to remove ammonia nitrogen from landfill leachate. Bench and pilot-scale adsorption experiments were performed with leachate collected from a closed sanitary landfill located in Curitiba, southern Brazil. At the bench-scale, two different heights of vermiculite and three different flow rates were tested using a fixed-bed column. These tests produced an average uptake capacity of 33.4 mg g-1 for the ammonia nitrogen concentration of 2,560 mg L-1. The Yan model was used to determine the breakthrough and the exhaustion times due to the best fit of the data to this model. At the pilot-scale, the flow rate was determined from the shortest length of the mass transfer zone obtained from bench-scale experiments. Tests were performed using one stainless-steel column filled with 26.2 kg of expanded vermiculite, which resulted in a bed height of 1.6 m. A leachate flow rate of approximately 350 L d-1 was applied to achieve the required contact time of 8.3 h. At this scale, an average uptake capacity of 18.1 mg g-1 was obtained for the ammonia nitrogen concentration of 1,193 mg L-1. It is worth mentioning that the flow rate and the concentration of the adsorbate in the feeding solution are fundamental to improve the operational time of the fixed-bed column. The main goal of this research was the determination of operating conditions to scale-up the adsorption process of ammonia nitrogen onto expanded vermiculite. The contact time was a key parameter to reach this goal.


Asunto(s)
Amoníaco , Contaminantes Químicos del Agua , Adsorción , Silicatos de Aluminio , Contaminantes Químicos del Agua/análisis , Nitrógeno/análisis
2.
Gigascience ; 112022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35639882

RESUMEN

BACKGROUND: Animal pollination is an important ecosystem function and service, ensuring both the integrity of natural systems and human well-being. Although many knowledge shortfalls remain, some high-quality data sets on biological interactions are now available. The development and adoption of standards for biodiversity data and metadata has promoted great advances in biological data sharing and aggregation, supporting large-scale studies and science-based public policies. However, these standards are currently not suitable to fully support interaction data sharing. RESULTS: Here we present a vocabulary of terms and a data model for sharing plant-pollinator interactions data based on the Darwin Core standard. The vocabulary introduces 48 new terms targeting several aspects of plant-pollinator interactions and can be used to capture information from different approaches and scales. Additionally, we provide solutions for data serialization using RDF, XML, and DwC-Archives and recommendations of existing controlled vocabularies for some of the terms. Our contribution supports open access to standardized data on plant-pollinator interactions. CONCLUSIONS: The adoption of the vocabulary would facilitate data sharing to support studies ranging from the spatial and temporal distribution of interactions to the taxonomic, phenological, functional, and phylogenetic aspects of plant-pollinator interactions. We expect to fill data and knowledge gaps, thus further enabling scientific research on the ecology and evolution of plant-pollinator communities, biodiversity conservation, ecosystem services, and the development of public policies. The proposed data model is flexible and can be adapted for sharing other types of interactions data by developing discipline-specific vocabularies of terms.


Asunto(s)
Ecosistema , Polinización , Animales , Biodiversidad , Filogenia , Estándares de Referencia
3.
J Clin Oncol ; 37(33): 3124-3131, 2019 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-31449470

RESUMEN

PURPOSE: Although chemoradiation therapy (CRT) with cisplatin remains the standard treatment of patients with locally advanced cervical cancer (LACC), 40% of patients present with disease recurrence. Additional treatment strategies are required to improve outcomes. We conducted a trial to evaluate the efficacy and safety of neoadjuvant chemotherapy (NAC) with cisplatin and gemcitabine followed by CRT. METHODS: In this phase II trial, patients with LACC (International Federation of Gynecology and Obstetrics stage IIB to IVA or with positive lymph nodes) were randomly assigned to three cycles of NAC with cisplatin and gemcitabine followed by standard CRT with weekly cisplatin plus pelvic radiotherapy or to standard CRT alone. The primary end point was 3-year progression-free survival (PFS). Secondary end points were response rate, 3-year locoregional control, 3-year overall survival (OS), safety, and quality of life. RESULTS: From 107 patients enrolled in the trial, 55 were randomly assigned to the NAC arm and 52 to the CRT-alone arm. The majority of patients had squamous cell carcinoma (87.8%). After a median follow-up of 31.7 months, NAC was associated with an inferior PFS, with 3-year PFS rates of 40.9% v 60.4% in the CRT arm (hazard ratio, 1.84; 95% CI, 1.04 to 3.26; P = .033). NAC also was associated with a lower OS (3-year OS rate, 60.7% v 86.8%; hazard ratio, 2.79; 95% CI, 1.29 to 6.01; P = .006). After treatment completion, complete response rates were 56.3% in the NAC arm and 80.3% in the CRT arm (P = .008). Toxicities were similar in both arms, with the exception of hypomagnesemia and neuropathy being more common with NAC. CONCLUSION: This study shows that the addition of NAC consisting of cisplatin and gemcitabine to standard CRT is not superior and is possibly inferior to CRT alone for the treatment of LACC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Cisplatino/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/radioterapia , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Quimioradioterapia , Quimioterapia Adyuvante , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Desoxicitidina/análogos & derivados , Femenino , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Cooperación del Paciente , Supervivencia sin Progresión , Adulto Joven , Gemcitabina
4.
Personal Neurosci ; 2: e8, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32435743

RESUMEN

Across a significant body of research, psychopathy has often been conceptualized as a biologically based malady. In this research, genetic and neurobiological differences have been conceptualized to underlie psychopathy, while affected individuals' life experiences only influence expressed psychopathic features and their severity. Psychopathy research has largely ignored developmental evidence demonstrating significant influences of environment on both biological and behavioral processes, resulting in several prominent criticisms (Edens & Vincent, 2008; Loeber, Byrd, & Farrington, 2015). The current review was conducted with two main aims: (a) to collect and consider etiological evidence from the extant body of research on genetic and neurobiological factors in psychopathy; and (b) to evaluate findings from genetic, neurotransmitter, brain structure, and brain function studies in the context of relevant evidence from developmental research. Examples from research on adversity and traumatic stress, a common correlate of psychopathy, were used to highlight current research gaps and future directions to aid in the integration of developmental and neurobiological research agendas. While some promising evidence exists regarding possible underlying neurobiological processes of psychopathic traits, this evidence is insufficient to suggest a largely biological etiology for the disorder. Further, information from developmental and epigenetic research may suggest complex, multidimensional trajectories for individuals experiencing psychopathy. Based on these observations, the authors make several recommendations for future research, as well as for current clinical application and practice.

5.
PLoS One ; 13(12): e0209406, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30596693

RESUMEN

Plant-pollinator networks have been widely used to understand the ecology of mutualistic interactions between plants and animals. While a number of general patterns have been identified, the mechanisms underlying the structure of plant-pollinator networks are poorly understood. Here we present an agent based model (ABM) that simulates the movement of bees over heterogeneous landscapes and captures pollination events, enabling the influence of landscape pattern on pollination networks to be explored. Using the model, we conducted a series of experiments using virtual landscapes representing a gradient of forest loss and fragmentation. The ABM was able to produce expected trends in network structure, from simulations of interactions between individual plants and pollinators. For example, results indicated an increase in the index of complementary specialization (H2') and a decline in network connectance with increasing forest cover. Furthermore, network nestedness was not associated with the degree of forest cover, but was positively related to forest patch size, further supporting results obtained in the field. This illustrates the potential value of ABMs for exploring the structure and dynamics of plant-pollinator networks, and for understanding the mechanisms that underlie them. We attribute the results obtained primarily to a shift from specialist to generalist pollinators with increasing forest loss, a trend that has been observed in some field situations.


Asunto(s)
Ecosistema , Bosques , Fenómenos Fisiológicos de las Plantas , Animales , Abejas/fisiología , Conservación de los Recursos Naturales , Humanos , Polinización/fisiología , Simbiosis/fisiología , Análisis de Sistemas
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