Bioevents correlation of planktic foraminifers and radiolarians from the Cenomanian to Turonian, southeastern Mexico

Abstrac

Crossover in the nature of the metallic phases in the perovskite-type RNiO_3

We have measured the photoemission spectra of Nd$_{1-x}$Sm$_{x}$NiO$_{3}$, where the metal-insulator transition and the N\'{e}el ordering occur at the same temperature for $x \lesssim 0.4$ and the metal-insulator transition temperature ($T_{MI}$) is higher than the N\'{e}el temperature for $x \gtrsim 0.4$. For $x \le 0.4$, the spectral intensity at the Fermi level is high in the metallic phase above $T_{MI}$ and gradually decreases with cooling in the insulating phase below $T_{MI}$ while for $x > 0.4$ it shows a pseudogap-like behavior above $T_{MI}$ and further diminishes below $T_{MI}$. The results clearly establish that there is a sharp change in the nature of the electronic correlations in the middle ($x \sim 0.4$) of the metallic phase of the $R$NiO$_3$ system.Comment: 4 pages, 4 figure, submitted to Phys. Rev.

Presentación, clasificación y evolución de los pacientes con carcinoma hepatocelular en un centro de Veracruz, México

ResumenAntecedentesLa estadificación en el carcinoma hepatocelular (CHC) otorga pronóstico y orientación terapéutica. La resección y el trasplante hepático son opciones curativas y las terapias de ablación se aplican a pacientes que no reciben tratamiento curativo. La sobrevida tras la resección hepática o terapias de ablación es variada.ObjetivoDescribir la presentación, la estadificación, el manejo y la evolución de los pacientes con CHC en nuestro centro.Pacientes y métodosCuarenta y dos pacientes fueron seguidos prospectivamente durante 7 años. La sobrevida se calculó mediante Kaplan-Meier y log-rank entre los sistemas de estadificación (Okuda, BCLC y CLIP) y tipos de tratamiento (resección hepática, ablación por radiofrecuencia y ningún tratamiento quirúrgico).ResultadosLa edad media ± desviación estándar de los pacientes fue 68,9 ± 9,5 años; el 57% fueron mujeres y el 54% cirróticos. El 31% tenía infección por VHC. El tamaño medio del tumor fue 6.48 ± 2.52cm. Los estadios CLIP 0, Okuda I y BCLC A tuvieron mejor sobrevida que otros estadios (p<0.05). La resección tuvo mejor sobrevida (mediana: 32 meses y sobrevida a 1, 3 y 5 años del 83, el 39 y 19.7%) que ablación por radiofrecuencia (25 meses, y el 90 y el 17.2% a 1 y 3 años) y que ningún tratamiento quirúrgico (1 año<5%) (p<0.05).ConclusiónLos pacientes con CHC en nuestro centro al igual que otra población en México son diagnosticados tardíamente. El pronóstico usando CLIP y BCLC es similar a la literatura. Los mejores resultados se observaron en estadios tempranos y los que tuvieron resección quirúrgica del CHC.AbstractBackgroundHepatocellular carcinoma (HCC) staging provides a basis for calculating disease prognosis and therapeutic guidance. Liver resection and transplantation are curative options, and ablation therapies are applied to patients that are not candidates for curative treatment. Survival after liver resection or ablation therapies varies.AimsTo describe the presentation, staging, management, and outcome in patients with HCC in our center.Patients and methodsForty-two patients had a 7-year prospective follow-up. Survival was calculated with the Kaplan-Meier analysis and the log-rank test was used for its comparison between the staging systems (Okuda, BCLC, and CLIP) and types of treatment (liver resection, radiofrequency ablation, and no surgical treatment).ResultsThe mean age of the patients was 68.9 ± 9.5 years; 57% were women. A total of 54% of the patients presented with cirrhosis and 31% were infected with hepatitis C virus (HCV). The mean tumor size was 6.48 ± 2.52cm. The CLIP 0, Okuda I, and BCLC A stages had better survival rates than the other stages (P<0.05). Survival with resection was superior (median of 32 months and survival at 1, 3, and 5 years of 83, 39, and 19.7%, respectively) to that of both radiofrequency ablation (median of 25 months and survival at 1 and 3 years of 90 and 17.2%, respectively) and no surgical treatment (1 year < 5%) (P<0.05).ConclusionThe patients at our center were diagnosed at late stages of HCC, as is the case in other Mexican populations. Outcome in relation to CLIP and BCLC was similar to the prognoses reported in the literature. The best results were observed in the patients with early stage disease and those that underwent HCC resection surgery

Investigating the impact of UV-C/H2O2 and sunlight/H2O2 on the removal of antibiotics, antibiotic resistance determinants and toxicity present in urban wastewater

This work aimed at exploring the impact of UV-C/H2O2 and sunlight/H2O2 processes, applied at pilot scale, on removing: (i) ciprofloxacin and sulfamethoxazole, (ii) cultivable Escherichia coli and Pseudomonas aeruginosa grown in the presence and absence of sub-minimal inhibitory concentrations of ciprofloxacin and sulfamethoxazole and (iii) the genes 16S rRNA and selected antibiotic resistance genes (ARGs) (i.e., sul1, blaCTX-M, qnrS, tetM, etc.) from urban wastewater. The major antibiotic transformation products (TPs) formed, were elucidated and the chronic toxicity of the whole effluent mixture against Vibrio fischeri was evaluated. The capability of the processes, in terms of the elimination of the antibiotics present in urban wastewater, varied among the two light sources used: both antibiotics were fully removed during UV-C/Η2Ο2, whereas only ciprofloxacin was removed during the sunlight/H2O2. The photo-transformation of the antibiotics led to the identification of 21 and 18 TPs of ciprofloxacin and sulfamethoxazole, respectively, while all of them retained their core moiety, responsible for the antibacterial activity. All the UV-C/H2O2-treated samples were found to be toxic, whereas the luminescence of V. fischeri was not inhibited when tested in the sunlight/H2O2-treated samples. During both processes, E. coli, P. aeruginosa and the colonies of these species still viable in the presence of antibiotics, were successfully inactivated to values below the detection limit. However, sunlight/H2O2 has not achieved complete disinfection, as regrowth of E. coli and P. aeruginosa colonies was observed after 48 h of storage of the treated effluent. Finally, none of the technologies tested was able to completely remove the target ARGs, confirming their inability to prevent the spread of resistance determinants to the environment.info:eu-repo/semantics/acceptedVersio

Selecting patterns and features for between- and within-crop-row weed mapping using UAV-imagery

This paper approaches the problem of weed mapping for precision agriculture, using imagery provided by Unmanned Aerial Vehicles (UAVs) from sunflower and maize crops. Precision agriculture referred to weed control is mainly based on the design of early post-emergence site-specific control treatments according to weed coverage, where one of the most important challenges is the spectral similarity of crop and weed pixels in early growth stages. Our work tackles this problem in the context of object-based image analysis (OBIA) by means of supervised machine learning methods combined with pattern and feature selection techniques, devising a strategy for alleviating the user intervention in the system while not compromising the accuracy. This work firstly proposes a method for choosing a set of training patterns via clustering techniques so as to consider a representative set of the whole field data spectrum for the classification method. Furthermore, a feature selection method is used to obtain the best discriminating features from a set of several statistics and measures of different nature. Results from this research show that the proposed method for pattern selection is suitable and leads to the construction of robust sets of data. The exploitation of different statistical, spatial and texture metrics represents a new avenue with huge potential for between and within crop-row weed mapping via UAV-imagery and shows good synergy when complemented with OBIA. Finally, there are some measures (specially those linked to vegetation indexes) that are of great influence for weed mapping in both sunflower and maize crops

Removal of nutrients and pesticides from agricultural runoff using microalgae and cyanobacteria

The use of pesticides in agriculture has ensured the production of different crops. However, pesticides have become an emerging public health problem for Latin American countries due to their excessive use, inadequate application, toxic characteristics, and minimal residue control. The current project evaluates the ability of two strains of algae (Chlorella and Scenedesmus sp.) and one cyanobacteria (Hapalosyphon sp.) to remove excess pesticides and other nutrients present in runoff water from rice production. Different concentrations of wastewater and carbon sources (Na2CO3 and NaHCO3 ) were evaluated. According to the results, all three strains can be grown in wastewater without dilution (100%), with a biomass concentration comparable to a synthetic medium. All three strains significantly reduced the concentration of NO3 and PO4 (95 and 85%, respectively), with no difference between Na2CO3 or NaHCO3 . Finally, Chlorella sp. obtained the highest removal efficiency of the pesticide (Chlorpyrifos), followed by Scenedesmus and Hapalosyphon sp. (100, 75, and 50%, respectively). This work shows that it is possible to use this type of waste as an alternative source of nutrients to obtain biomass and metabolites of interest, such as lipids and carbohydrates, to produce biofuels