Viewpoint: How the Graphene Could Help to Decrease SARS-CoV-2 Spread?

The COVID-19 (Coronavirus Disease 2019), caused by the SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) began in December 2019 in Wuhan, China. Until February 2021, there are 110 million of infected people, 60 million have recovered and approximately 2.5 million have passed away worldwide according to WHO. The coronavirus pandemic is evolving very rapidly and represents a risk for health care workers and society in general. Moreover, pandemic has tested the limits of health systems by raising questions about forms of prevention, management of infections with conventional therapies and the use of diagnostic tools. In this article we discussed the possible role of the nanostructured-graphene based materials as aid tools for preventing the spread and infection of SARS-CoV-2. In this regard, nanotechnology could take part in the fight against the spread of future diseases caused by deadly viruses. However, its use should be well founded in terms of biocompatibility. Therefore, we have proposed an approach based on graphene nanomaterials as possible allies for the fight against the COVID-19 spread based on the physicochemical features that present these novel nanomaterials

Tendencias bibliométricas de las publicaciones sobre resistencia a antimicrobianos en Escherichia coli en Perú de 2009-2019.

Antibiotic resistance is a growing problem worldwide. While the most visible aspect is the direct effect of antimicrobial resistance in clinical settings, this problem affects all microorganisms in all environments. Nevertheless, most of the data available on antibiotic resistance outside clinical settings are from high-income countries, with the current situation in most low- and middle-income countries remaining under-reported. Escherichia coli is considered a good marker of “antibiotic pressure” due to its cosmopolitan distribution. In this scenario, we selected E. coli as an appropriate microorganism to perform an initial bibliometric analysis of publications focused on antimicrobial resistance outside disease-causing microorganisms. Thus, the present manuscript performs an analysis of the studies reporting measurable levels of antibiotic resistance of E. coli not causing human disease in Peru published during the period from 2009-2019. Following a search in PubMed and Google, 35 documents were selected as reporting measurable data of antibiotic resistance. Of these, 8 (22.8%) were reported in thesis format. The mean delay between sampling and publishing in article format was 3.7 years, with one study having been published 18 years after sampling. The number of publications developed in Peru describing antimicrobial resistance levels in E. coli out of hospital settings in the period 2009-2019 is scarce. Of these, a relevant number is of unpublished thesis. These findings showing the gap of knowledge and lack of accessible data about antimicrobial resistance out of hospital environments. Efforts and strategies must be developed to fill this knowledge gap.La resistencia a antibióticos es un problema creciente a nivel mundial. Aunque el aspecto más visible es el efecto de la resistencia a antimicrobianos en ambientes hospitalarios, este problema afecta todos los ambientes. No obstante, la mayoría de los datos sobre resistencia antimicrobiana allende ambientes hospitalarios son de países de alta renta, siendo escasa la información sobre la situación en países de baja y media renta. Escherichia coli se considera un buen marcador de "presión antibiótica" debido a su distribución cosmopolita. En este escenario seleccionamos E. coli como microorganismo ideal para realizar un análisis bibliométrico de publicaciones, del periodo 2009-2019, que se centrasen en el estudio de la resistencia a antimicrobianos en E. coli no causantes de enfermedad en humanos en Perú. Tras una búsqueda en PubMed y Google, se seleccionaron 35 documentos que reportasen datos cuantificables de resistencia a antimicrobianos. De estos, 8 (22.8%) fueron tesis. La media de tiempo entre muestreo y publicación de artículo fue de 3.7 años, con un estudio habiéndose publicado 18 años después del muestreo. El número de publicaciones realizadas en Perú en el periodo 2009-2019 describiendo la resistencia a antimicrobianos de E. coli fuera del ámbito clínico es escaso. De estas, reseñar la presencia de un elevado número de tesis. Estos hechos muestran un vacío de conocimiento y una falta de datos accesibles sobre resistencia a antimicrobianos fuera de ámbitos hospitalarios. Se han de desarrollar esfuerzos y estrategias para acabar con este vacío de conocimiento

Bacterias promotoras de crecimiento de plantas autóctonas y su efecto en "Prosopis chilensis" (Molina) Stunz

Today in Mexico are being deforestated the species Prosopis spp. for use as firewood and charcoal, in various arid regions of the country. For its production a synthetic fertilizer is used, thus there is an increase in soil, groundwater and aquifers salinity. This research was conducted in Santa Ana, Sonora, Mexico in 2006. Were isolated and purified microorganisms associated with the root system of Prosopis glandulosa growing in craters of the volcanic area from El Pinacate and Gran Desierto de Altar, Sonora Biosphere Reserve. The plant growth-promoting bacteria present the peculiarity of fixing atmospheric nitrogen; the effect of the isolates on germination and seedling development in P. chilensiswas measured. 19 colonies were isolated; of them, only one bacterial colony showed high acetylene reduction activity and ability to solubilize phosphate, was identified as Bacillus amyloliquefaciens. Our results suggest that B. amyloliquefaciens, has a particular affinity to grow from 0 to 0.75M of NaCl and develops at temperatures of 30 to 50 °C. The effects of inoculation of B. amyloliquefaciens, along with A. halopraeferens, showed favorable results in the increase of germination and seedling development of P. chilensis. This is the first report of B. amyloliquefaciensas a plant growth promoting bacteria associated with P. glandulosa.En la actualidad se está deforestando en México la especie de Prosopis spp. para utilizarse como leña y carbón, en diferentes zonas áridas de nuestro país. Para su producción se utiliza fertilizante sintético, con ello hay un incremento de salinidad del suelo, subsuelo y mantos acuíferos. La presente investigación se realizó en Santa Ana, Sonora, México en 2006. Se aislaron y purificaron microorganismos asociados al sistema radicular de Prosopis glandulosa que se desarrolla en cráteres de la zona volcánica de la reserva de la biosfera El Pinacate y Gran Desierto de Altar Sonora. Las bacterias promotoras de crecimiento de plantas presentan la peculiaridad de fijar el nitrógeno atmosférico; se midió el efecto de las cepas aisladas en germinación y en el desarrollo en plántulas de P. chilensis. Fueron aisladas 19 colonias; de ellas, solamente una colonia bacteriana mostró alta actividad de reducción de acetileno y capacidad de solubilizar fosfatos, se identificó como Bacillus amyloliquefaciens. Nuestros resultados sugieren que B. amyloliquefaciens, presenta una afinidad particular para crecer de 0 a 0.75 M de NaCl y desarrollarse en temperaturas de 30 a 50 °C. Los efectos de la inoculación de B. amyloliquefaciens, conjuntamente con A. halopraeferens, mostraron reultados favorables en el incremento de la germinación y el desarrollo de plántulas de P. chilensis. Éste es el primer reporte de B. amyloliquefaciens como bacteria promora de crecimiento de plantas asociada a P. glandulosa

Ameliorative effects of salt resistance on physiological parameters in the halophyte Salicornia bigelovii torr. with plant growth-promoting rhizobacteria

Salicornia bigelovii is a promising resource to cultivate under extreme climatic conditions of arid-desert regions. However, the production of Salicornia depends on the appropriate supplementation of nitrogen rich synthetic fertilizers. Application of specific halotolerant nitrogen-fixing bacteria associated with S. bigelovii could be an important practice for crop production in salt-affected regions. Seedlings of S. bigelovii were inoculated and developed with plant growth promoting rhizobacteria (Klebsiella pnseumoniae) at different salinities (0 and 0.25 M NaCl) grown under in vitro conditions. The inoculation increased growth and physiological activity at a high salinity. The major benefits of inoculation were observed on total seedlings biomass (320 and 175 g at 0 and 0.25 M NaCl, respectively) and adjacent branches of stem biomass (150 and 85 g at 0 and 0.25 M NaCl, respectively). The inoculation with Klebsiella pneumoniae also significantly improved seedlings salinity tolerance compared to the noninoculated controls. In non-salinity conditions, the inoculated seedlings enhanced the CO2 fixation and O2 evolution. The non-inoculated controls were more sensitive to salinity than inoculated seedlings exposed to salinity, as indicated by several measured parameters. Moreover, inoculated seedlings had significantly increase on proline, phenolics content, but not significant in starch compared to noninoculated controls. In conclusion, K. pneumoniae inoculation mitigates the salinity effects and promotes the Salicornia growth.Keywords: Salicornia bigelovii, Klebsiella pneumoniae, halophyte, ecotype, stress salinity. African Journal of Biotechnology Vol. 12(34), pp. 5278-528

Experiencia peruana sobre el flujograma de diagnóstico del virus de inmunodeficiencia humana: Peruvian experience on the human immunodeficiency virus diagnostic flowchart

Mr Editor:The Joint United Nations Program on HIV/AIDS (UNAIDS) proposed as a goal that the countries reach 95-95-95 by the year 2030, in other words, that 95% of people living with HIV (PLH) are diagnosed and of these that 95% receive antiretroviral treatment (ART) and at least 95% have undetectable viral load or viral suppression.Sr. Editor:El Programa Conjunto de las Naciones Unidas sobre el VIH/Sida (ONUSIDA) propuso como meta que los países alcancen para el año 2030 el 95-95-95, es decir que un 95% de personas viviendo con VIH (PVV) estén diagnosticadas y de éstas que el 95% reciban tratamiento antirretroviral (TAR) y al menos el 95% tengan carga viral indetectable o supresión viral

USE OF MORINGA SEED (Moringa oleifera Lam.) AS A BIOCOAGULANT TO IMPROVE SURFACE WATER QUALITY

Using Moringa oleifera (Moringa oleifera Lam.) seed as a biocoagulant to enhance surface water's physical and chemical quality was the goal of this study. The methodology applied for the generation of experimental data was through the use of the Jar Test equipment, in a dose of 40 mg/L to 140 mg/L, then a fast mixing of 100 rpm for 1 minute and a slow mixing of 40 rpm for 10 minutes was performed, and sedimentation was left for 5 to 30 minutes, with 5 minutes intervals between each dose. The results show that an optimal biocoagulant dose of 100 mg/L at 20 minutes produced a turbidity reduction effectiveness of 97.06%. Hardness fell by 12% of its starting value, conductivity and total dissolved solids increased dramatically, and there was a 92.3% reduction in perceived colour, which showed that the use of Moringa seeds as a coagulant had a favourable effect on reducing the concentration of turbidity and colour. Because of this, Moringa (Moringa oleifera Lam.) can be used as a natural source to purify drinking water. The Tukey HSD test applied to the turbidity removal percentages, indicates that the means are not significantly different. However, the experimental evaluation indicates that after 20 minutes, the best results are obtained

Matching Dendrochronological Dates with the Southern Hemisphere ¹⁴C Bomb Curve to Confirm Annual Tree Rings in Pseudolmedia rigida from Bolivia

This study used high-precision radiocarbon bomb-pulse dating of selected wood rings to provide an independent validation of the tree growth periodicity of Pseudolmedia rigida (Klotzsch & H. Karst.) Cuatrec. from the Moraceae family, collected in the Madidi National Park in Bolivia. ¹⁴C content was measured by accelerator mass spectrometry (AMS) in 10 samples from a single tree covering over 70 yr from 1939 to 2011. These preliminary calendar dates were determined by dendrochronological techniques and were also used to select the samples for ¹⁴C AMS. In order to validate these preliminary dates using the established Southern Hemisphere (SH) ¹⁴C atmospheric concentration data set, the targeted rings were selected to be formed during periods before and after the ¹⁴C bomb spike nuclear tests (i.e. 1950s–1960s). The excellent agreement of the dendrochronological dates and the ¹⁴C signatures in tree rings associated with the same dates provided by the bombpulse ¹⁴C atmospheric values for the SH (SHCal zone 1–2) confirms the annual periodicity of the observed growth layers, and thus the high potential of this species for tree-ring analysis. The lack of discrepancies between both data sets also suggests that there are no significant latitudinal differences between the ¹⁴C SHCal zone 1–2 curve and the ¹⁴C values obtained from the selected tree rings at this geographic location (14°33′S, 68°49′W) in South America. The annual resolution of P. rigida tree rings opens the possibility of broader applications of dendrochronological analysis for ecological and paleoclimatic studies in the Bolivian tropics, as well as the possibility of using wood samples from some tree species from this region to improve the quality of the bomb-pulse ¹⁴C SHCal curve at this latitude

Social interactions and business portfolio among vegetable produc-ers in central Mexico

Objective: Analyze social interactions and business portfolio of vegetable producers in Central Mexico. Design/methodology/approach: we worked with 16 small vegetable producers. Semi-structured questionnaires and periodic monitoring were used in field to collect data. A Social Network analysis was carried out to know social interactions between producers, and the Boston Consulting Group (BCG) and Ansoff matrix for the business portfolio. Results: We found that the products with potential in the market were lettuce and nopal. Broccoli and squash represent low sales and low utility. Producers with a higher degree of centrality grow lettuce, broccoli and squash, so we suggested to develop strategies for introducing nopal. Limitations on study/implications: It was necessary to deep in market and consumers analysis.Objective: To analyze the social interactions and business portfolio of vegetable producers in central Mexico. Design/methodology/approach: Work was conducted with 16 small-scale vegetable producers. Semi-structured questionnaires and periodic monitoring were used in the field to collect data. A Social Network analysis was carried out to understand the social interactions between producers, and the Boston Consulting Group (BCG) and Ansoff matrix was used for the business portfolio. Results: The study found that the products with potential in the market were lettuce and nopal. Broccoli and squash represent low sales and low utility. Producers with a higher degree of centrality grow lettuce, broccoli and squash, so we suggested developing strategies for introducing nopal. Limitations on study/implications: It was necessary to delve into market and consumers analysis

Very high energy particle acceleration powered by the jets of the microquasar SS 433

SS 433 is a binary system containing a supergiant star that is overflowing its Roche lobe with matter accreting onto a compact object (either a black hole or neutron star). Two jets of ionized matter with a bulk velocity of $\sim0.26c$ extend from the binary, perpendicular to the line of sight, and terminate inside W50, a supernova remnant that is being distorted by the jets. SS 433 differs from other microquasars in that the accretion is believed to be super-Eddington, and the luminosity of the system is $\sim10^{40}$ erg s$^{-1}$. The lobes of W50 in which the jets terminate, about 40 pc from the central source, are expected to accelerate charged particles, and indeed radio and X-ray emission consistent with electron synchrotron emission in a magnetic field have been observed. At higher energies (>100 GeV), the particle fluxes of $\gamma$ rays from X-ray hotspots around SS 433 have been reported as flux upper limits. In this energy regime, it has been unclear whether the emission is dominated by electrons that are interacting with photons from the cosmic microwave background through inverse-Compton scattering or by protons interacting with the ambient gas. Here we report TeV $\gamma$-ray observations of the SS 433/W50 system where the lobes are spatially resolved. The TeV emission is localized to structures in the lobes, far from the center of the system where the jets are formed. We have measured photon energies of at least 25 TeV, and these are certainly not Doppler boosted, because of the viewing geometry. We conclude that the emission from radio to TeV energies is consistent with a single population of electrons with energies extending to at least hundreds of TeV in a magnetic field of $\sim16$~micro-Gauss.Comment: Preprint version of Nature paper. Contacts: S. BenZvi, B. Dingus, K. Fang, C.D. Rho , H. Zhang, H. Zho