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1,746 result(s) for "Padilla, C."
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Improving breast and colorectal screening uptake in France. One map to target intervention areas
Abstract Background Most intervention areas for improving cancer screening uptake are in deprived neighbourhoods. However, in recent years, determinants and attitudes to screening have evolved, and new perspectives are needed in understanding cancer screening practices. It is therefore necessary to develop simple, effective and reproducible strategies for identifying intervention areas. Using one map, the aim is to investigate spatially and temporally breast and colorectal cancer screening in France from 2015-2016 to 2021-2022. Methods Uptake in breast (BS) and colorectal (CS) cancer screening at the census block level was generated by the regional cancer screening centre for women aged 50 to 74, residing in the Rhône department (mostly rural but including the urban Lyon metropolitan area). We used spatial analysis to create a map highlighting groups of hotspots, identifying their direction of propagation between 2015-2019 and 2020-2022. Results The results reveal interesting areas for intervention with differences and similarities in uptake of the two screenings. For CS, there was a 5-pt increase in uptake between the two periods (2015-2019: 33% and 2020-2022: 38%), whereas for BS the uptake remained stagnant around 49% on average in the metropolitan area. The map highlights 49 urban census blocks with consistently lower uptake rates in both screenings (39.2% for BS, 23.7% for CS) than the overall average. Conversely, some census blocks have consistently lower uptake rates on one screening but not on the other (CS or BS). Conclusions This work may inform the breast and colorectal locally screening trend and inform policymakers to develop tailored prevention strategies. These analyses are easily reproducible at different times and spaces, and they have the potential for evaluation and comparison of screening uptake. Key messages • Maps may inform policymakers to develop tailored prevention strategies. • Investigate spatially and temporally breast and colorectal cancer screening reveal interesting areas for interventions.
Role of native defects on the opto-electronic properties of p-type ZnO synthesized during the most straightforward method: only water
The influence of predominant native defects in forming ZnO with p-type conductivity is discussed in this work when the semiconductor is synthesized only in water. The semiconductor was prepared by dissolving a Zn-salt in deionized water at 80 °C. The powders were thermally treated at 400 °C in an air atmosphere to obtain well-defined crystalline ZnO. XRD, SEM, EDS, Raman spectroscopy, diffuse reflectance, photoluminescence, and Seebeck effect techniques were used to characterize the synthesized material. The results showed a well-crystalline semiconductor in wurtzite phase. The crystal-oriented growth was the (002) plane. The sample morphology was formed by highly ordered sticks-like. The optoelectronic characterization showed that the synthesized ZnO had a lower band gap than that reported in the literature. It was related to deep energy levels corresponding to oxygen interstitials as the predominant native defects. Raman, EPR, and photoluminescence spectra analysis corroborated the existence of native defects in the crystalline structure. The p-type conductivity of the sample was determined by Seebeck coefficient analysis. A synthesis reaction mechanism involving the formation of oxygen interstitials was proposed in this work. Understanding the effects of native defects in wide band gap semiconductors is necessary to design new materials for sensors or energy conversion applications.
Single cell analyses reveal contrasting life strategies of the two main nitrifiers in the ocean
Nitrification, the oxidation of ammonia via nitrite to nitrate, is a key process in marine nitrogen (N) cycling. Although oceanic ammonia and nitrite oxidation are balanced, ammonia-oxidizing archaea (AOA) vastly outnumber the main nitrite oxidizers, the bacterial Nitrospinae. The ecophysiological reasons for this discrepancy in abundance are unclear. Here, we compare substrate utilization and growth of Nitrospinae to AOA in the Gulf of Mexico. Based on our results, more than half of the Nitrospinae cellular N-demand is met by the organic-N compounds urea and cyanate, while AOA mainly assimilate ammonium. Nitrospinae have, under in situ conditions, around four-times higher biomass yield and five-times higher growth rates than AOA, despite their ten-fold lower abundance. Our combined results indicate that differences in mortality between Nitrospinae and AOA, rather than thermodynamics, biomass yield and cell size, determine the abundances of these main marine nitrifiers. Furthermore, there is no need to invoke yet undiscovered, abundant nitrite oxidizers to explain nitrification rates in the ocean. Ammonia oxidizing archaea and Nitrospinae are the main known nitrifiers in the ocean, but the much greater abundance of the former is puzzling. Here, the authors show that differences in mortality, rather than thermodynamics, cell size or biomass yield, explain the discrepancy, without the need to invoke yet undiscovered, abundant nitrite oxidizers.
SAR11 bacteria linked to ocean anoxia and nitrogen loss
Bacteria of the SAR11 clade constitute up to one half of all microbial cells in the oxygen-rich surface ocean. SAR11 bacteria are also abundant in oxygen minimum zones (OMZs), where oxygen falls below detection and anaerobic microbes have vital roles in converting bioavailable nitrogen to N 2 gas. Anaerobic metabolism has not yet been observed in SAR11, and it remains unknown how these bacteria contribute to OMZ biogeochemical cycling. Here, genomic analysis of single cells from the world’s largest OMZ revealed previously uncharacterized SAR11 lineages with adaptations for life without oxygen, including genes for respiratory nitrate reductases (Nar). SAR11 nar genes were experimentally verified to encode proteins catalysing the nitrite-producing first step of denitrification and constituted ~40% of OMZ nar transcripts, with transcription peaking in the anoxic zone of maximum nitrate reduction activity. These results link SAR11 to pathways of ocean nitrogen loss, redefining the ecological niche of Earth’s most abundant organismal group. Bacteria of the SAR11 clade constitute up to one half of all marine microbes and are thought to require oxygen for growth; here, a subgroup of SAR11 bacteria are shown to thrive in ocean oxygen minimum zones and to encode abundant respiratory nitrate reductases. An anoxic niche for SAR11 bacteria SAR11 bacteria, the most abundant type of microbe in the world's oceans, are thought to require oxygen for growth, yet they are also abundant in waters where oxygen levels are low. Frank Stewart and colleagues show here that a subgroup of SAR11 bacteria that thrives in ocean oxygen minimum zones have adapted to the microaerobic/anaerobic conditions there, and they encode abundant respiratory nitrate reductases that perform the first step in denitrification. These results redefine the ecological niche of Earth's most abundant organismal group and suggest that they are substantial contributors to nitrogen loss in oxygen minimum zones.
Conducting Functional Communication Training via Telehealth to Reduce the Problem Behavior of Young Children with Autism
Functional communication training (FCT) was conducted by parents of 17 young children with autism spectrum disorders who displayed problem behavior. All procedures were conducted at regional clinics located an average of 15 miles from the families’ homes. Parents received coaching via telehealth from behavior consultants who were located an average of 222 miles from the regional clinics. Parents first conducted functional analyses with telehealth consultation (Wacker, Lee et al. Journal of Applied Behavior Analysis , in press ) and then conducted FCT that was matched to the identified function of problem behavior. Parent assistants located at the regional clinics received brief training in the procedures and supported the families during the clinic visits. FCT, conducted within a nonconcurrent multiple baseline design, reduced problem behavior by an average of 93.5 %. Results suggested that FCT can be conducted by parents via telehealth when experienced applied behavior analysts provide consultation.
Synthesis of Pd-Cu/TPPCu electrocatalyst for direct ethanol fuel cell applications
In this study, the electro-oxidation reaction of ethanol over Pd–Cu supported on Cu porphyrin (TPPCu) was investigated. The catalyst was synthesized using the microwave-assisted polyol method and physicochemically characterized by XRD, XPS, SEM, EDS, TEM, EDAX, UV–Vis, FTIR, and RBS. A Cu-enriched catalyst with Cu 3 Pd, Pd,Cu, and TPPCu phases was identified using XRD and XPS. However, according to the RBS results, the catalytic surface was enriched with Pd, indicating that the interaction between TPPCu and Pd–Cu allowed the presence of Pd on the surface, thus enhancing the catalytic response of the material. This synthesis prevented the deprotonation of porphyrin on the electrocatalyst, as confirmed by XPS analysis. Electrochemical studies based on cyclic voltammetry and electrochemical impedance spectroscopy were used to investigate the response of the catalyst to variations in the scan rate and increasing ethanol concentration. The electrochemical response of PdCu/TPPCu improved with an increasing number of cycles, indicating improved mass transport, thus improving its electrochemical response and tolerance to CO contamination. This catalyst exhibited a high electroactive surface area of 49.4 m 2 /g, which could be related to the presence of TPPCu as a support. The behavior of the catalyst on the anode of a fuel cell fed with ethanol, bioethanol, and bioethanol residues was evaluated. Graphical Abstract
Effects of freeze-thaw on the biomechanical and structural properties of the rat Achilles tendon
Rodent models are commonly used to investigate tendon healing, with the biomechanical and structural properties of the healed tendons being important outcome measures. Tendon storage for later testing becomes necessary when performing large experiments with multiple time-points. However, it is unclear whether freezing rodent tendons affects their material properties. Thus the aim of this study was to determine whether freezing rat Achilles tendons affects their biomechanical or structural properties. Tendons were frozen at either −20 °C or −80 °C directly after harvesting, or tested when freshly harvested. Groups of tendons were subjected to several freeze-thaw cycles (1, 2, and 5) within 3 months, or frozen for 9 months, after which the tendons were subjected to biomechanical testing. Additionally, fresh and thawed tendons were compared morphologically, histologically and by transmission electron microscopy. No major differences in biomechanical properties were found between fresh tendons and those frozen once or twice at −20 °C or −80 °C. However, deterioration of tendon properties was found for 5-cycle groups and both long-term freezing groups; after 9 months of freezing at −80 °C the tear resistance of the tendon was reduced from 125.4 ± 16.4N to 74.3 ± 18.4N (p = 0.0132). Moreover, tendons stored under these conditions showed major disruption of collagen fibrils when examined by transmission electron microscopy. When examined histologically, fresh samples exhibited the best cellularity and proteoglycan content of the enthesis. These properties were preserved better after freezing at −80 °C than after freezing at −20 °C, which resulted in markedly smaller chondrocytes and less proteoglycan content. Overall, the best preservation of histological integrity was seen with tendons frozen once at −80 °C. In conclusion, rat Achilles tendons can be frozen once or twice for short periods of time (up to 3 months) at −20 °C or −80 °C for later testing. However, freezing for 9 months at either −20 °C or −80 °C leads to deterioration of certain parameters.
Cyanate and urea are substrates for nitrification by Thaumarchaeota in the marine environment
Ammonia-oxidizing archaea of the phylum Thaumarchaeota are among the most abundant marine microorganisms 1 . These organisms thrive in the oceans despite ammonium being present at low nanomolar concentrations 2 , 3 . Some Thaumarchaeota isolates have been shown to utilize urea and cyanate as energy and N sources through intracellular conversion to ammonium 4 – 6 . Yet, it is unclear whether patterns observed in culture extend to marine Thaumarchaeota, and whether Thaumarchaeota in the ocean directly utilize urea and cyanate or rely on co-occurring microorganisms to break these substrates down to ammonium. Urea utilization has been reported for marine ammonia-oxidizing communities 7 – 10 , but no evidence of cyanate utilization exists for marine ammonia oxidizers. Here, we demonstrate that in the Gulf of Mexico, Thaumarchaeota use urea and cyanate both directly and indirectly as energy and N sources. We observed substantial and linear rates of nitrite production from urea and cyanate additions, which often persisted even when ammonium was added to micromolar concentrations. Furthermore, single-cell analysis revealed that the Thaumarchaeota incorporated ammonium-, urea- and cyanate-derived N at significantly higher rates than most other microorganisms. Yet, no cyanases were detected in thaumarchaeal genomic data from the Gulf of Mexico. Therefore, we tested cyanate utilization in Nitrosopumilus maritimus , which also lacks a canonical cyanase, and showed that cyanate was oxidized to nitrite. Our findings demonstrate that marine Thaumarchaeota can use urea and cyanate as both an energy and N source. On the basis of these results, we hypothesize that urea and cyanate are substrates for ammonia-oxidizing Thaumarchaeota throughout the ocean. Thaumarchaeota isolates are capable of utilizing urea and cyanate for nitrification in vitro. Here, the authors show that this occurs in situ and that Thaumarchaeota are able to use urea and cyanate as an energy and nitrogen source in the marine environment.
Single cell genomic and transcriptomic evidence for the use of alternative nitrogen substrates by anammox bacteria
Anaerobic ammonium oxidation (anammox) contributes substantially to ocean nitrogen loss, particularly in anoxic marine zones (AMZs). Ammonium is scarce in AMZs, raising the hypothesis that organic nitrogen compounds may be ammonium sources for anammox. Biochemical measurements suggest that the organic compounds urea and cyanate can support anammox in AMZs. However, it is unclear if anammox bacteria degrade these compounds to ammonium themselves, or rely on other organisms for this process. Genes for urea degradation have not been found in anammox bacteria, and genomic evidence for cyanate use for anammox is limited to a cyanase gene recovered from the sediment bacterium Candidatus Scalindua profunda. Here, analysis of Ca . Scalindua single amplified genomes from the Eastern Tropical North Pacific AMZ revealed genes for urea degradation and transport, as well as for cyanate degradation. Urease and cyanase genes were transcribed, along with anammox genes, in the AMZ core where anammox rates peaked. Homologs of these genes were also detected in meta-omic datasets from major AMZs in the Eastern Tropical South Pacific and Arabian Sea. These results suggest that anammox bacteria from different ocean regions can directly access organic nitrogen substrates. Future studies should assess if and under what environmental conditions these substrates contribute to the ammonium budget for anammox.