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1.
Phys Rev Lett ; 126(16): 162701, 2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33961456

RESUMEN

Many neutron star properties, such as the proton fraction, reflect the symmetry energy contributions to the equation of state that dominate when neutron and proton densities differ strongly. To constrain these contributions at suprasaturation densities, we measure the spectra of charged pions produced by colliding rare isotope tin (Sn) beams with isotopically enriched Sn targets. Using ratios of the charged pion spectra measured at high transverse momenta, we deduce the slope of the symmetry energy to be 42

2.
Acta Paediatr ; 107(8): 1322-1326, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29603358

RESUMEN

AIM: Extensive ongoing research on probiotics and infant formulas raises a number of safety questions. One concern is the potential influence of d-lactic acid-containing preparations on the health of infants and children. The aim of this review was to summarise the available knowledge on the ingestion of d-lactic acid-producing bacteria, acidified infant formulas and fermented infant formulas as a potential cause of paediatric d-lactic acidosis. METHODS: A Medline database search was performed in July 2017, with no restrictions on the language, article type or publication date. The 1715 search results were screened for clinical trials, review articles, case series and case reports of relevance to the topic. RESULTS: We identified five randomised controlled trials from 2005 to 2017 covering 544 healthy infants and some case reports and experimental studies. No clinically relevant adverse effects of d-lactic acid-producing probiotics and fermented infant formulas were described in healthy children. However, a harmless, subclinical accumulation of d-lactate was theoretically possible. The only known cases of paediatric d-lactic acidosis occurred in patients with short bowel syndrome or, historically, in infants fed with acidified formulas. CONCLUSION: Our main finding was that probiotics and fermented formulas did not cause d-lactic acidosis in healthy children.


Asunto(s)
Acidosis Láctica/etiología , Fórmulas Infantiles/química , Salud del Lactante , Ácido Láctico/administración & dosificación , Probióticos/uso terapéutico , Acidosis Láctica/fisiopatología , Preescolar , Femenino , Fermentación , Humanos , Lactante , Masculino , Probióticos/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Medición de Riesgo , Sensibilidad y Especificidad
3.
Benef Microbes ; : 1-17, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38964747

RESUMEN

The effectiveness of probiotics in preventing or reversing antibiotic-induced microbiome disruption remains uncertain, and claims of microbiome restoration to its pre-antibiotic state may be overestimated. In this review, we aimed to assess the efficacy of probiotics in preventing or ameliorating disruptions in microbiome composition and function induced by antibiotic treatment. We searched Medline, Embase, and CENTRAL for randomised controlled and non-randomised trials. Participants were individuals of any age who were on systemic antibiotics with a low risk of baseline dysbiosis. The intervention consisted of probiotics during or after antibiotic treatment, compared to placebo, alternative interventions, or no intervention. Outcomes included microbiome composition and diversity analysed using high-throughput molecular methods, alongside microbial function and resistome assessments. Seven studies, reported in eight papers, were reviewed. One study showed probiotics counteracting antibiotic-induced diversity changes, another showed exacerbation of these changes, and four others showed no effect. Effects on taxa abundance ranged from mitigating dysbiosis to selective modulation, no effect, or delayed recovery. One study observed no impact on the resistome, while another reported an increase in antibiotic resistance genes. In conclusion, heterogeneous results preclude a definitive conclusion on the effectiveness of any specific probiotic in restoring antibiotic-exposed microbiomes. For a clearer understanding, future research should be more standardised and long-term, employing advanced methods, such as 16S rRNA gene sequencing and metagenomic sequencing. These studies should strive to include larger, diverse populations to enhance generalisability and clearly define what constitutes a healthy microbiome. Finally, linking changes in the microbiome to specific clinical outcomes is essential for clinical decision making. PROSPERO registration number: CRD42023446214.

4.
J Appl Microbiol ; 110(6): 1571-83, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21447014

RESUMEN

AIMS: Research into the relationship between pathogens, faecal indicator microbes and environmental factors in beach sand has been limited, yet vital to the understanding of the microbial relationship between sand and the water column and to the improvement of criteria for better human health protection at beaches. The objectives of this study were to evaluate the presence and distribution of pathogens in various zones of beach sand (subtidal, intertidal and supratidal) and to assess their relationship with environmental parameters and indicator microbes at a non-point source subtropical marine beach. METHODS AND RESULTS: In this exploratory study in subtropical Miami (Florida, USA), beach sand samples were collected and analysed over the course of 6 days for several pathogens, microbial source tracking markers and indicator microbes. An inverse correlation between moisture content and most indicator microbes was found. Significant associations were identified between some indicator microbes and pathogens (such as nematode larvae and yeasts in the genus Candida), which are from classes of microbes that are rarely evaluated in the context of recreational beach use. CONCLUSIONS: Results indicate that indicator microbes may predict the presence of some of the pathogens, in particular helminthes, yeasts and the bacterial pathogen Staphylococcus aureus including methicillin-resistant forms. Indicator microbes may thus be useful for monitoring beach sand and water quality at non-point source beaches. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of both indicator microbes and pathogens in beach sand provides one possible explanation for human health effects reported at non-point sources beaches.


Asunto(s)
Bacterias/aislamiento & purificación , Playas , Monitoreo del Ambiente/métodos , Helmintos/aislamiento & purificación , Microbiología del Agua , Levaduras/aislamiento & purificación , Animales , Recuento de Colonia Microbiana , Florida , Agua de Mar/microbiología , Agua de Mar/parasitología , Dióxido de Silicio/análisis
5.
Rev Sci Instrum ; 92(6): 063302, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34243507

RESUMEN

The Superconducting Analyzer for MUlti-particles from RAdioIsotope (SAMURAI) Pion-Reconstruction and Ion-Tracker Time Projection Chamber (SπRIT TPC) was designed to enable measurements of heavy ion collisions with the SAMURAI spectrometer at the RIKEN radioactive isotope beam factory and provides constraints on the equation of state of neutron-rich nuclear matter. The SπRIT TPC has a 50.5 cm drift length and an 86.4 × 134.4 cm2 pad plane with 12 096 pads that are equipped with the generic electronics for TPCs. The SπRIT TPC allows for an excellent reconstruction of particles and provides isotopic resolution for pions and other light charged particles across a wide range of energy losses and momenta. The details of the SπRIT TPC are presented, along with discussion of the TPC performance based on cosmic rays and charged particles emitted in heavy ion collisions.

6.
Phys Rev Lett ; 105(14): 142701, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21230826

RESUMEN

Fragment partitions of fragmenting hot nuclei produced in central and semiperipheral collisions have been compared in the excitation energy region 4-10 MeV per nucleon where radial collective expansion takes place. It is shown that, for a given total excitation energy per nucleon, the amount of radial collective energy fixes the mean fragment multiplicity. It is also shown that, at a given total excitation energy per nucleon, the different properties of fragment partitions are completely determined by the reduced fragment multiplicity (i.e., normalized to the source size). Freeze-out volumes seem to play a role in the scalings observed.

7.
Water Res ; 41(16): 3747-57, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17544051

RESUMEN

The effect of a stormwater conveyance system on indicator bacteria levels at a Florida beach was assessed using microbial source tracking methods, and by investigating indicator bacteria population structure in water and sediments. During a rain event, regulatory standards for both fecal coliforms and Enterococcus spp. were exceeded, contrasting with significantly lower levels under dry conditions. Indicator bacteria levels were high in sediments under all conditions. The involvement of human sewage in the contamination was investigated using polymerase chain reaction (PCR) assays for the esp gene of Enterococcus faecium and for the conserved T antigen of human polyomaviruses, all of which were negative. BOX-PCR subtyping of Escherichia coli and Enterococcus showed higher population diversity during the rain event; and higher population similarity during dry conditions, suggesting that without fresh inputs, only a subset of the population survives the selective pressure of the secondary habitat. These data indicate that high indicator bacteria levels were attributable to a stormwater system that acted as a reservoir and conduit, flushing high levels of indicator bacteria to the beach during a rain event. Such environmental reservoirs of indicator bacteria further complicate the already questionable relationship between indicator organisms and human pathogens, and call for a better understanding of the ecology, fate and persistence of indicator bacteria.


Asunto(s)
Bacterias/aislamiento & purificación , Playas/normas , Agua Dulce/microbiología , Lluvia/microbiología , ADN Viral/análisis , Enterococcus/aislamiento & purificación , Enterococcus faecium , Escherichia coli/aislamiento & purificación , Heces/microbiología , Florida , Humanos , Reacción en Cadena de la Polimerasa , Poliomavirus , Contaminación del Agua/análisis
8.
Sci Rep ; 5: 9380, 2015 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-25797885

RESUMEN

To preserve environmental and human health, improved treatment processes are needed to reduce nutrients, microbes, and emerging chemical contaminants from domestic wastewater prior to discharge into the environment. Electrocoagulation (EC) treatment is increasingly used to treat industrial wastewater; however, this technology has not yet been thoroughly assessed for its potential to reduce concentrations of nutrients, a variety of microbial surrogates, and personal care products found in domestic wastewater. This investigation's objective was to determine the efficiency of a benchtop EC unit with aluminum sacrificial electrodes to reduce concentrations of the aforementioned biological and chemical pollutants from raw and tertiary-treated domestic wastewater. EC treatment resulted in significant reductions (p < 0.05, α = 0.05) in phosphate, all microbial surrogates, and several personal care products from raw and tertiary-treated domestic wastewater. When wastewater was augmented with microbial surrogates representing bacterial, viral, and protozoan pathogens to measure the extent of reduction, EC treatment resulted in up to 7-log10 reduction of microbial surrogates. Future pilot and full-scale investigations are needed to optimize EC treatment for the following: reducing nitrogen species, personal care products, and energy consumption; elucidating the mechanisms behind microbial reductions; and performing life cycle analyses to determine the appropriateness of implementation.


Asunto(s)
Técnicas Electroquímicas , Aguas Residuales , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Aluminio , Bacillus subtilis/aislamiento & purificación , Electrodos , Enterococcus faecalis/aislamiento & purificación , Diseño de Equipo , Escherichia coli/aislamiento & purificación , Humanos , Nitrógeno/química , Nitrógeno/aislamiento & purificación , Fosfatos/química , Fosfatos/aislamiento & purificación , Aguas Residuales/química , Aguas Residuales/microbiología , Purificación del Agua/instrumentación
9.
Water Res ; 35(17): 4011-8, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11791830

RESUMEN

Since Zoogloea ramigera has been considered to be important in aerobic wastewater treatment, we have evaluated several methods for detecting and enumerating Z. ramigera in water and wastewater samples. Indirect immunoassay methods for the detection of Zoogloea strains were developed using polyclonal antibodies against the cells or the isolated exocellular polymer (EP) of the neotype Zoogloea ramigera strain 106 (ATCC 19544). The primary antibodies reacted with the cells and the exopolymer associated with finger-like zoogloeal projections, but not with other bacteria from natural samples. These antibodies allowed detection of Z. ramigera in environmental samples. Scanning electron microscopy (SEM) was used to show that the cells and the exocellular polymer of naturally occurring zoogloeal projections are antigenically and structurally related to those of Z. ramigera 106. Both immunological procedures and probes complementary to regions on the 16S rRNA could detect Z. ramigera in natural samples but the immunological procedures were easier to use. RT-PCR was also used to detect Z. ramigera in natural samples. These methods were also used to identify Z. ramigera in biofilms that developed over wastewater samples as part of an MPN procedure that was used to quantitate Z. ramigera at different stages of the wastewater treatment process and in different lakes. Z. ramigera could be found in all stages of wastewa ter treatment processes, from raw wastewater to chlorinated effluent, The highest concentration of Z. ramigera was found in the mixed liquor stage of the a wastewater treatment plant. Additionally, Z. ramigera was found in all eutrophic and mesotrophic lakes and in some oligotrophic lakes.


Asunto(s)
Purificación del Agua , Zoogloea/inmunología , Biopelículas , ADN Bacteriano/análisis , Monitoreo del Ambiente/métodos , Inmunoensayo , Dinámica Poblacional , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Eliminación de Residuos Líquidos , Zoogloea/genética
10.
J Food Prot ; 64(3): 292-7, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11252469

RESUMEN

This study compared the effect of different physical and chemical treatments of strawberries and tomatoes to determine their ability to recover seeded viral and bacterial pathogens from produce surfaces. Solutions of salts, amino acids, complex media, and detergents were compared as eluants. Phosphate-buffered saline (PBS) containing 0.1% Tween 80 eluted the highest number of seeded microorganisms. Elution with this defined solution was then compared under different conditions of physical agitation. Rotary shaking for 20 min at 36 degrees C eluted higher numbers of viruses and bacteria than did low- or high-speed stomaching. Commercially available and laboratory prepared bacteriological differential media were compared for their ability to recover and distinguish eluted Salmonella Montevideo and Escherichia coli O157:H7 strains from seeded produce. The recovery of seeded bacterial pathogens was low when differential media containing selective ingredients were used (MacConkey sorbitol agar, XLD agar, MacConkey agar). Highest recoveries were obtained on a medium consisting of tryptic soy agar supplemented with sodium thiosulfate and ferric ammonium citrate compared with selective media that inhibited up to 50% of the growth of the eluted microorganisms.


Asunto(s)
Bacteriófagos/aislamiento & purificación , Escherichia coli O157/aislamiento & purificación , Frutas/microbiología , Poliovirus/aislamiento & purificación , Salmonella/aislamiento & purificación , Solanum lycopersicum/microbiología , Técnicas Bacteriológicas , Bacteriófagos/crecimiento & desarrollo , Recuento de Colonia Microbiana , Medios de Cultivo , Escherichia coli O157/crecimiento & desarrollo , Frutas/virología , Solanum lycopersicum/virología , Poliovirus/crecimiento & desarrollo , Salmonella/crecimiento & desarrollo
11.
Water Environ Res ; 73(6): 711-20, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11833765

RESUMEN

The Upper Occoquan Sewage Authority (UOSA) Water Reclamation Plant, Centreville, Virginia, is a state-of-the-art wastewater treatment plant that was created to treat area wastewater and provide protection for the Occoquan Reservoir. This study investigated UOSA's unit processes as barriers to pathogenic as well as altemative and traditional-indicator microorganisms. Samples were collected once a month for 1 year from eight sites within UOSA's advanced wastewater reclamation plant. The eight sites were monitored for indicator bacteria total and fecal coliforms, enterococci, Clostridium, coliphage (the virus that infects Escherichia coli), human enteroviruses, and enteric protozoa. Overall, the plant was able to achieve a 5- to 7-log10 reduction of bacteria, 5-log10 reduction of enteroviruses, 4-log10 reduction for Clostridium, and 4.6-log10 reduction of protozoa. Total coliforms, enterococci, Clostridium, coliphage, Cryptosporidium, and Giardia were all detected in four or fewer samples of the final effluent. No enteroviruses or fecal coliforms were detected in the final effluent. The microbiological quality of reclaimed water and the reservoir water were compared. In every case, the treated wastewater was of a better quality than the ambient water in the reservoir, thus indicating that the reclaimed water will not adversely affect the water quality for downstream users.


Asunto(s)
Monitoreo del Ambiente , Aguas del Alcantarillado/microbiología , Microbiología del Agua , Purificación del Agua/métodos , Animales , Clostridium/aislamiento & purificación , Conservación de los Recursos Naturales , Cryptosporidium/aislamiento & purificación , Enterobacteriaceae/aislamiento & purificación , Giardia/aislamiento & purificación , Humanos , Salud Pública , Control de Calidad
12.
Water Res ; 65: 257-70, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25129566

RESUMEN

Wastewater treatment ponds (WTP) are one of the most widespread treatment technologies in the world; however, the mechanisms and extent of enteric virus removal in these systems are poorly understood. Two WTP systems in Bolivia, with similar overall hydraulic retention times but different first stages of treatment, were analyzed for enteric virus removal. One system consisted of a facultative pond followed by two maturation ponds (three-pond system) and the other consisted of an upflow anaerobic sludge blanket (UASB) reactor followed by two maturation (polishing) ponds (UASB-pond system). Quantitative polymerase chain reaction with reverse transcription (RT-qPCR) was used to measure concentrations of norovirus, rotavirus, and pepper mild mottle virus, while cell culture methods were used to measure concentrations of culturable enteroviruses (EV). Limited virus removal was observed with RT-qPCR in either system; however, the three-pond system removed culturable EV with greater efficiency than the UASB-pond system. The majority of viruses were not associated with particles and only a small proportion was associated with particles larger than 180 µm; thus, it is unlikely that sedimentation is a major mechanism of virus removal. High concentrations of viruses were associated with particles between 0.45 and 180 µm in the UASB reactor effluent, but not in the facultative pond effluent. The association of viruses with this size class of particles may explain why only minimal virus removal was observed in the UASB-pond system. Quantitative microbial risk assessment of the treated effluent for reuse for restricted irrigation indicated that the three-pond system effluent requires an additional 1- to 2-log10 reduction of viruses to achieve the WHO health target of <10(-4) disability-adjusted life years (DALYs) lost per person per year; however, the UASB-pond system effluent may require an additional 2.5- to 4.5-log10 reduction of viruses.


Asunto(s)
Enterovirus/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/virología , Purificación del Agua/métodos , Riego Agrícola , Animales , Bolivia , Línea Celular , Chlorocebus aethiops , Enterovirus/genética , Tamaño de la Partícula , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Medición de Riesgo , Abastecimiento de Agua
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