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Enteroaggregative E. coli(EAEC) is one of the most frequent pathogens isolated from diarrheal patients as well as from healthy individuals in Brazil and has recently also been implicated as an extraintestinal pathogenic E. coli(ExPEC) associated with bloodstream and urinary tract infections. In this study, 37 EAEC isolates, obtained from fecal samples of non-diarrheic children, were molecularly and phenotypically characterized to access the pathogenic features of these isolates. The EAEC isolates were assigned into the phylogroups A (54.1%), D (29.7%), B1 (13.5%) and B2 (2.7%); and harbored genes responsible for encoding the major pilin subunit of the aggregative adherence fimbriae (AAFs) or aggregate-forming pili (AFP) adhesins as follows: aggA(24.3%), agg3A(5.4%), agg4A(27.0%), agg5A(32.4%) and afpA(10.8%). The most frequent O:H serotypes were O15:H2 (8.1%), O38:H25 (5.4%) and O86:H2 (5.4%). Twenty-one isolates (56.8%) produce the aggregative adherence (AA) pattern on HeLa cells, and biofilm formation was more efficient among EAEC isolates harboring the aggAand agg5Agenes. PFGE analysis showed that 31 (83.8%) of the isolates were classified into 10 distinct clusters, which reinforces the high diversity found among the isolates studied. Of note, 40.5% (15/37) of the EAEC isolates have a genetic profile compatible with E. coliisolates with intrinsic potential to cause extraintestinal infections in healthy individuals, and therefore, classified as EAEC/ExPEC hybrids. In conclusion, we showed the presence of EAEC/ExPEC hybrids in the intestinal microbiota of non-diarrheic children, possibly representing the source of some endogenous extraintestinal infections.

Zn, Zr-based catalysts were prepared by dry impregnation and employed in the synthesis of isobutene from ethanol in the presence of water. The catalysts were characterized by means of several techniques such as XPS, XRD, N2physical adsorption, HRTEM, NH3-TPD, EPR, CO2-TPD, XRF, ethanol-TPD, and CO2/H2-TPSR. The mechanism of isobutene synthesis from ethanol was examined using density functional theory (DFT) calculations. This work shows that employing the wetness impregnation procedure makes it possible to replace Zr4+on m-ZrO2with Zn2+, generating oxygen vacancies and Zr3+(cus) species on the ZrO2surface. It was observed that the Zn solubility limit in m-ZrO2is reached above 6 at% Zn. The Zn2+and oxygen vacancies on the surface of m-ZrO2drastically changed the catalytic behavior of this oxide. They promote the generation of acetaldehyde from ethanol and also acetone from this aldehyde. Moreover, the Zn2+and oxygen vacancies play a pivotal role in the rate-limiting step of this cascade reaction, which involves the conversion of acetone into isobutene and more specifically acetaldehyde enolate species condensation. This phenomenon was very well described by the linear correlation obtained between the Zn concentration on the m-ZrO2surface and the yield of isobutene. Finally, this paper presents new perspectives for the generation of isobutene from ethanol, shedding light on the mechanism of this rather complex process.

Background AIDS-related cytomegalovirus (CMV) encephalitis has declined in the combined antiretroviral therapy (ART) era in high-income countries. However, there is scarce information on CMV encephalitis in low- and middle-income countries. The objectives of this study were to identify the prevalence of AIDS-related CMV encephalitis and describe its main features.Methods This was a retrospective cohort study carried out at a referral center in São Paulo, Brazil. We included adult people living with HIV/AIDS (PLWHA), hospitalized in 2019, with a CD4 cell count ≤100/mm3and quantitation CMV DNA results in plasma. Cases with compatible neurological manifestations and detection of CMV DNA by polymerase chain reaction (PCR) in cerebrospinal fluid samples were defined as CMV encephalitis.Results Among 761 PLWHA hospitalized, 248 (32.5%) cases were included in this study. Prevalence of CMV encephalitis was 2.4% (6/248) among all included cases and 7.7% (6/78) among individuals with neurological opportunistic diseases. The six patients with CMV encephalitis were males and had CD4 cell count <50/mm3. Five (83%) cases had CMV encephalitis as AIDS-defining disease and showed CMV DNA detection by PCR >50,000 UI/mL plasma. All six cases received anti-CMV therapy (ganciclovir, n= 4; ganciclovir plus foscarnet, n= 2) and five were discharged to home. CMV encephalitis was not uncommon among hospitalized PLWHA with neurological opportunistic diseases.Conclusions The epidemiological and immunological profile of individuals with CMV encephalitis was similar to that described in the pre-ART era, but in contrast, most cases were treated and discharged from the hospital.

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This paper presents a novel methodology based on Principal Components Analysis (PCA) and Affine Policies (AP) for self-scheduling of a price-taker Compressed Air Energy Storage (CAES) facility operating under uncertainties. The proposed PCA-AP model is developed from the facility owner's perspective, which partakes in energy, spinning, and idle reserve markets. A methodology is proposed to select the required price uncertainty intervals from actual data based on a Box Cox technique. For a more realistic representation, the detailed thermodynamic characteristics of the CAES facility are considered, taking into account as well modern CAES facilities that may charge and discharge concurrently. To validate the proposed PCA-AP model and approach, the results obtained are compared with an existing Affine Arithmetic (AA) model, which is also based on an affine approach, and Monte Carlo Simulations (MCS), which can be considered as the benchmark for comparison purposes. The input data, forecast prices and intervals of uncertainty, are taken from the Ontario-Canada electricity market for 2015-2019. From the studies presented, it can be observed that the new PCA-AP approach provides less conservative results as compared to the AA approach, and hence can be considered an adequate methodology for day-ahead operations in systems with significant sources of uncertainty.

As the penetration of variable renewable generation increases in power systems, issues, such as grid stiffness, larger frequency deviations, and grid stability, are becoming more relevant, particularly in view of 100% renewable energy networks, which is the future of smart grids. In this context, energy storage systems (ESSs) are proving to be indispensable for facilitating the integration of renewable energy sources (RESs), are being widely deployed in both microgrids and bulk power systems, and thus will be the hallmark of the clean electrical grids of the future. Hence, this article reviews several energy storage technologies that are rapidly evolving to address the RES integration challenge, particularly compressed air energy storage (CAES), flywheels, batteries, and thermal ESSs, and their modeling and applications in power grids. An overview of these ESSs is provided, focusing on new models and applications in microgrids and distribution and transmission grids for grid operation, markets, stability, and control.

Background There is scarce information on AIDS-related cytomegalovirus (CMV) retinitis in middle-income countries. The objectives of this study were to identify the prevalence of active CMV retinitis in severely immunosuppressed people living with HIV (PLWHIV) and to describe its main features.Methods This retrospective cohort study was carried out at a tertiary center in São Paulo, Brazil. We included hospitalized adults PLWHIV with CD4 count ≤100 cells/μL, ≥ one quantitation of CMV DNA in plasma, and indirect ophthalmoscopy evaluation.Results Thirty-eight (21.6%) of 176 participants had at least an ophthalmoscopy diagnosis and only 3 (1.7%) individuals presented active CMV retinitis. All these participants were male, and retinitis was asymptomatic in 2 cases. Two participants had extraocular end-organ CMV disease and detectable CMV DNA in plasma.Conclusions These results show a low prevalence of active CMV retinitis in the evaluated population. However, 2 of 3 participants had asymptomatic active CMV retinitis and a fifth of participants had at least one ophthalmoscopy diagnosis, suggesting the need for routine ophthalmologic evaluation in hospitalized severely immunosuppressed PLWHIV. The profile of participants with active CMV retinitis was similar to that described in the pre-ART era and quantitation of CMV DNA in plasma was variable.

IMPORTANCE: The choice between posterior cervical foraminotomy (posterior surgery) and anterior cervical discectomy with fusion (anterior surgery) for cervical foraminal radiculopathy remains controversial. OBJECTIVE: To investigate the noninferiority of posterior vs anterior surgery in patients with cervical foraminal radiculopathy with regard to clinical outcomes after 1 year. DESIGN, SETTING, AND PARTICIPANTS: This multicenter investigator-blinded noninferiority randomized clinical trial was conducted from January 2016 to May 2020 with a total follow-up of 2 years. Patients were included from 9 hospitals in the Netherlands. Of 389 adult patients with 1-sided single-level cervical foraminal radiculopathy screened for eligibility, 124 declined to participate or did not meet eligibility criteria. Patients with pure axial neck pain without radicular pain were not eligible. Of 265 patients randomized (132 to posterior and 133 to anterior), 15 were lost to follow-up and 228 were included in the 1-year analysis (110 in posterior and 118 in anterior). INTERVENTIONS: Patients were randomly assigned 1:1 to posterior foraminotomy or anterior cervical discectomy with fusion. MAIN OUTCOMES AND MEASURES: Primary outcomes were proportion of success using Odom criteria and decrease in arm pain using a visual analogue scale from 0 to 100 with a noninferiority margin of 10% (assuming advantages with posterior surgery over anterior surgery that would justify a tolerable loss of efficacy of 10%). Secondary outcomes were neck pain, disability, quality of life, work status, treatment satisfaction, reoperations, and complications. Analyses were performed with 2-proportion z tests at 1-sided .05 significance levels with Bonferroni corrections. RESULTS: Among 265 included patients, the mean (SD) age was 51.2 (8.3) years; 133 patients (50%) were female and 132 (50%) were male. Patients were randomly assigned to posterior (132) or anterior (133) surgery. The proportion of success was 0.88 (86 of 98) in the posterior surgery group and 0.76 (81 of 106) in the anterior surgery group (difference, −0.11 percentage points; 1-sided 95% CI, −0.01) and the between-group difference in arm pain was −2.8 (1-sided 95% CI, −9.4) at 1-year follow-up, indicating noninferiority of posterior surgery. Decrease in arm pain had a between-group difference of 3.4 (1-sided 95% CI, 11.8), crossing the noninferiority margin with 1.8 points. All secondary outcomes had 2-sided 95% CIs clustered around 0 with small between-group differences. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, posterior surgery was noninferior to anterior surgery for patients with cervical radiculopathy regarding success rate and arm pain at 1 year. Decrease in arm pain and secondary outcomes had small between-group differences. These results may be used to enhance shared decision-making. TRIAL REGISTRATION: Netherlands Trial Register Identifier: NTR5536

Purpose: To compare the Atraumatic Restorative Treatment (ART) associated with Brix3000™ to ART considering treatment time, pain experienced, and acceptability to children. Methods: This study was accepted in Research Ethics Committee in July 2019 (number 3469402). Healthy patients (n= 20) aged 3–9 years, with at least one primary molar with occlusal dentine caries without cusp involvement were randomly allocated to either the ART + Brix3000™ group or the ART-only group. The sample was characterised by sex, age, tooth location and caries experience. Time spent and pain experience scores were recorded at prophylaxis, caries removal and restoration. The pain experience (intense, moderate, or mild) was evaluated by the Face, Legs, Activity, Cry, Consolability-revised scale (FLACC-r). Acceptability was assessed by a five-point hedonic facial scale (dichotomised into ‘like’ and ‘indifferent/dislike’ bins) and by an open-question interview. Mann–Whitney, Chi-square, and Fisher’s exact tests were applied to discern differences in time, pain/sample characterisation and acceptability, respectively. Results: The ART + Brix3000™ group required 8.6 ± 3.1 min to remove caries tissue, whereas the ART group required only 4.8 ± 2.0 min (p= 0.03). The total time spent with treatments was 13.1 ± 4.0 min for ART + Brix3000™, and 9.8 ± 2.7 min for ART (p= 0.03). There was no difference in pain experience and acceptability found among the groups (p> 0.05). Conclusion: Although the ART + Brix3000™ technique demanded more treatment time than the ART alone, there were no differences in either pain experience or acceptability.

The association between the intensity of obstructive sleep apnea and skeletal alterations in the face and hyoid bone is still scarcely addressed in the literature.

Purpose: To evaluate the prevalence of sleep disorders in Brazilian preschool children and its associations with parental report of dental pain and discomfort. Methods: This cross-sectional study involved 604 Brazilian preschoolers (4–5 years old). Sleep disorders (SD) and the parental report of dental pain and discomfort (DPD) were evaluated using the Brazilian versions of the Sleep Disturbance Scale for Children (SDSC) and the Dental Discomfort Questionnaire (DDQ-B), respectively. Bivariate and multivariate Poisson regression analyses with robust variance were performed to analyze the association between SDSC and DP. Results: Prevalence of SD ranged from 7 to 21%. 7.9% of the children had DPD indicating the need for more invasive dental procedures (DDQ-B ≥ 5). Significant associations were found between DPD and the following SDSC domains: sleep hyperhidrosis (p= 0.024; PRa= 1.38; 95% CI: 1.04–1.83), disorders of initiating and maintaining sleep (p&lt; 0.001; PRa= 1.41; 95% CI: 1.15–1.73), parasomnias (p&lt; 0.001; PRa= 1.82; 95% CI: 1.39–2.37), and sleep–wake transition disorders (p= 0.018; PRa= 1.28; 95% CI: 1.04–1.58). Children with higher prevalence of DPD presented 20% higher prevalence of SD than children lower prevalence of DPD (p= 0.039; PRa= 1.20; 95% CI: 1.01–1.44). Conclusion: Preschool children with higher prevalence of DPD are more likely to have SD, such as hyperhidrosis, disorders of initiating and maintaining sleep, parasomnias, and sleep–wake transition.

We describe a process for obtaining nanocrystalline cellulose (NC) by either acidic (H–NC) or alkaline treatment (OH–NC) of microcrystalline cellulose, which was subsequently bonded to magnetic nanoparticles (H-NC-MNP and OH-NC-MNP) and used as support for the immobilization of Aspergillus oryzae(H-NC-MNP-Ao and OH-NC-MNP-Ao) and Kluyveromyces lactis(H-NC-MNP-Kl and OH-NC-MNP-Kl) β-galactosidases. The mean size of magnetic nanocellulose particles was approximately 75 nm. All derivatives reached saturation magnetizations of 7–18 emu/g, with a coercivity of approximately 4 kOe. Derivatives could be applied in batch hydrolysis of lactose either in permeate or in cheese whey for 30× and it reached hydrolysis higher than 50%. Furthermore, using a continuous process in a column packed-bed reactor, the derivative OH-NC-MNP-Ao had capacity to hydrolyze over 50% of the lactose present in milk or whey after 24 h of reaction. Fungal β-galactosidases immobilized on magnetic nanocellulose can be applied in lactose hydrolysis using batch or continuous processes.

Characterizing point defects that produce deep states in nanostructures is imperative when designing next-generation electronic and optoelectronic devices. Light emission and carrier transport properties are strongly influenced by the energy position and concentration of such states. The primary objective of this work is to fingerprint the electronic structure by characterizing the deep levels using a combined optical and electronic characterization, considering ZnSe nanowires as an example. Specifically, we use low temperature photoluminescence spectroscopy to identify the dominant recombination mechanisms and determine the total defect concentration. The carrier concentration and mobility are then calculated from electron transport measurements using single nanowire field effect transistors, and the measured experimental data were used to construct a model describing the types, energies, and ionized fraction of defects and calculate the deviation from stoichiometry. This metrology is hence demonstrated to provide an unambiguous means to determine a material’s electronic structure.

Geraniol is a monoterpene alcohol that is derived from the essential oils of aromatic plants, with anti-inflammatory, antimicrobial, antioxidant and neuroprotective properties. This study characterized the effect of geraniol on behavior and brainwave patterns in rats. Male rats were submitted to administration of geraniol (25, 50 and 100 mg/kg). The hole board (HB) and open field (OF) tests were performed to evaluate anxiety and motor behavior, respectively. In addition, barbiturate-induced sleeping time (BIST) was used to analyze sedative effect. Finally, electrocorticogram (ECoG) recordings were used to characterize brain-wave patterns. The results showed that geraniol treatment in rats decreased the distance traveled, rearing numbers and lead to increase in immobility time in HB and OF tests. In BIST test, geraniol treatment increased sleep duration but not sleep latency in the animals. Furthermore, geraniol-treated animals demonstrated an increase in the percentage of delta waves in the total spectrum power. Taken together, our results suggested that geraniol exerted a depressant effect on the central nervous system of rats.

Lead zirconate titanate (PZT) is a wide versatile material applied in several electronic devices. Some of dielectric and piezoelectric characteristics depend on phase formation, crystallization and composition. In this work, we prepare PZT powder samples with different compositions by the Polymeric Precursor Method, which were thermally treated at very low temperatures in order to get amorphised powder samples. The zirconium-rich PZT6040 sample showed a significant uptake in photoluminescent emission between 320 oC and 350 oC, followed by a slightly increasing in bandgap energy. In spite of the bandgap energy posses the typical value for several structurally disordered semiconductors, these effects were associated to the coexistence of pyrochlore and tetragonal perovskite phases in that referred conditions.

Many synthesis methods are available to obtain a set of specific characteristics for lead zirconate titanate (PZT) piezoelectric ceramic powders. In this work, we have successfully prepared PZT powder samples through the Polymeric Precursor Method with x = 0.6, according the general formula Pb (ZrxTi1-x)O3. The powders were thermally treated from 380 to 550 oC and characterized by Raman spectroscopy and X-ray diffraction (DRX) in order to evaluate the effects of thermal treatment on the phase formation and the crystallization processes. The results obtained by Raman spectroscopy were compared to refined crystal data obtained by Rietveld method, leading to coherent conclusions about the structural effects occurring along the temperature of calcination. It was possible to characterize the tetragonal perovskite phase as predominant phase occurs only after 500 oC, but its crystallinity is already determined by synthesis method. Thus, no ordering process is verified for perovskite as a function of the temperature increasing during thermal treatment, in spite of the continuous pyrochlore-to-perovskite phase transition. The pyrochlore secondary phase starts to vanish before its proper crystallization process, changing the tetragonality of previously formed perovskite phase.

Hydrotalcite are anionic clay material presenting LDH arrangement and high porosity and specific areas, which make it a good adsorbent for pollutant species in water. Besides that, that material type can be used as catalyst or catalyst support in several industrial processes. The most common compositions is based on metallic mix hydroxide with high content of magnesium, but their adsorptive properties arise from aluminum replacement in layer structure. The present work presents the synthesis of carbonated magnesium-aluminum hydrotalcite through the precipitation method in order to investigate the co-insertion of iron (III) in aluminum site. It was found the iron (III) co-inserted samples obtained at 100 and 200 oC for 4 hours present no substantial harming in relation to the common magnesium-aluminum composition. All of the samples presented high porosity and specific area, becoming an alternative anionic adsorptive.

A visible-light-driven strategy for hydroacylation and epoxyacylation of olefins in water using methylene blue as photoredox catalyst and persulfate as oxidant is reported. In this unprecedented unified approach, two different transformations are accomplished using only one set of reagents. The method has a broad scope spanning a range of aromatic and aliphatic aldehydes as well as conjugated and nonconjugated olefins to deliver ketones and epoxyketones from abundant and inexpensive chemical feedstocks.

This study showed clinical differences between 73 patients with chronic obstructive pulmonary disease who improved and those who did not improve health-related quality of life after a comprehensive pulmonary rehabilitation program. There were more disease-related exacerbations and comorbidities associated with decreased healthrelated quality of life after pulmonary rehabilitation.

Zinc is vital for the physiology of oceanic phytoplankton. The striking similarity of the depth profiles of zinc to those of silicate suggests that the uptake of both elements into the opaline frustules of diatoms, and their regeneration from these frustules, should be coupled. However, the zinc content of diatom opal is negligible, and zinc is taken up into and regenerated from the organic parts of diatom cells. Thus, since opaline frustules dissolve deep in the water column while organic material is regenerated in the shallow subsurface ocean, there is little reason to expect the observed close similarity between zinc and silicate, and the dissimilarity between zinc and phosphate. Here we combine observations with simulations using a three-dimensional model of ocean circulation and biogeochemistry to show that the coupled distribution of zinc and silicate, as well as the decoupling of zinc and phosphate, can arise in the absence of mechanistic links between the uptake of zinc and silicate, and despite contrasting regeneration length scales. Our simulations indicate that the oceanic zinc distribution is, in fact, a natural result of the interaction between ocean biogeochemistry and the physical circulation through the Southern Ocean hub. Our analysis demonstrates the importance of uptake stoichiometry in controlling ocean biogeochemistry, and the utility of global-scale elemental covariation in the ocean in understanding these controls.

The stability characteristics of incompressible, viscoelastic planar jets are investigated in the present work. The Oldroyd-B constitutive equation represents the viscoelastic fluid behavior. Linear stability theory is used to study the sinuous and varicose stability modes’ growth rates, wave velocity, and neutral curves as a function of the Weissenberg number, Reynolds number, and solvent viscosity coefficient. A canonical velocity profile gives the laminar jet base flow. The polymer stress tensor components are computed considering a parallel flow approximation, verified by comparing profiles with stress tensor profiles obtained by computational fluid dynamic simulations. The modified Orr–Sommerfeld equation with included viscoelastic effects is solved by a shooting method. The results show that viscoelastic effects become significant for low Reynolds numbers, stabilizing the sinuous mode and destabilizing the varicose mode compared to the Newtonian jet stability results. Neutral curves are also presented, showing the viscoelastic effects on the critical Reynolds number and the possible existence of elastic instability in the limit of low Reynolds numbers.

Background/Objectives:: Stearoyl-CoA desaturase-2 (SCD2) is the main d9 desaturase expressed in the central nervous system. Because of its potential involvement in controlling whole-body adiposity, we evaluated the expression and function of SCD2 in the hypothalami of mice. Subjects/Methods:: Male mice of different strains were used in real-time PCR, immunoblot and metabolic experiments. In addition, antisense oligonucleotides and lentiviral vectors were used to reduce and increase the expression of SCD2 in the hypothalamus. Results:: The level of SCD2 in the hypothalamus is similar to other regions of the central nervous system and is ~10-fold higher than in any other region of the body. In the arcuate nucleus, SCD2 is expressed in proopiomelanocortin and neuropeptide-Y neurons. Upon high fat feeding, the level of hypothalamic SCD2 increases. Inhibition of hypothalamic SCD2 as accomplished by two distinct approaches, an antisense oligonucleotide or a short-hairpin RNA delivered by a lentivirus, resulted in reduced body mass gain mostly due to increased energy expenditure and increased spontaneous activity. Increasing hypothalamic SCD2 by a lentivirus approach resulted in no change in body mass and food intake. Conclusions:: Thus, SCD2 is highly expressed in the hypothalami of rodents and its knockdown reduces body mass due to increased whole-body energy expenditure.