Releasing antiferromagnetic skyrmions from local magnetic-anisotropy defects.

Lattice defects may work as a kind of apparatus for catching topological excitations, preventing their escape. So, the problem of removing skyrmions from eventual local defects in magnetic materials must be closely related to new technologies such as skyrmionic. Here, we examine the conditions for drawing a skyrmion from a magnetic impurity in a two-dimensional antiferromagnetic system by applying spin-polarized currents (SPC). Two types of impurities are investigated (local easy-axis and easy-plane anisotropy defects). Also, two methods to release the skyrmion with SPC are explored. In principle, our results could be qualitatively relevant to any other type of lattice defect.

Antibacterial activity of Thymus vulgaris (thyme) essential oil against strains of Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus saprophyticus isolated from meat product.

Meat products represent an important component of the human diet and are a good source of nutrients. Food-borne microorganisms are the main pathogens that cause human diseases as a result of food consumption, especially products of animal origin. The objective of the present research was to verify the antibacterial activity of the essential oil of Thymus vulgaris against strains of Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus saprophyticus isolated from meat products. For this, the analyses of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were performed in microdilution plates. The association of the product with antimicrobials was also studied using disk diffusion. And the anti-adherent activity, which was determined in the presence of sucrose, in glass tubes. Thyme oil showed a strong inhibitory activity against K. pneumoniae, P. aeruginosa and S. saprophyticus, with the MIC values ranging from 64 to 512 µg/mL, and bactericidal effect for most strains, with MBC values ranging from 256 to 1,024 µg/mL. T. vulgaris oil exhibited varied interactions in association with the antimicrobials, with synergistic (41.67%), indifferent (50%) and antagonistic (8.33%) effects. Regarding the anti-adherent activity, the test product was effective in inhibiting the adherence of all bacterial strains under study. Therefore, thyme oil presents itself as an antibacterial and anti-adherent agent against K. pneumoniae, P. aeruginosa and S. saprophyticus, being a natural product that can represent an interesting alternative in the efforts to combat foodborne diseases.

Oral Manifestations in Patients with COVID-19: A 6-Month Update.

This is the first update of the previously published living systematic review that summarized evidence on the prevalence of oral signs and symptoms in patients with COVID-19. Hitherto, 183 studies were included, reporting data from 64,876 patients with COVID-19 worldwide. The overall prevalence of taste disorders was 38% (95% CI = 22% to 56%, I2 = 98%). Hypogeusia, dysgeusia, and ageusia were also evaluated by a meta-analysis, and the pooled prevalence was 34% for hypogeusia, 33% for dysgeusia, and 26% for ageusia. Taste disorders were associated with a positive COVID-19 test (odds ratio [OR] = 7.54, 95% CI = 5.24 to 10.86, I2 = 93%, P < 0.00001), showing high certainty of evidence. However, the association between taste disorders and mild/moderate severity of COVID-19 (OR = 1.63, 95% CI = 1.33 to 1.99, I2 = 69%, P < 0.0001) and female patients with COVID-19 (OR = 1.77, 95% CI = 1.26 to 2.48, I2 = 79%, P = 0.001) presented low certainty of evidence. Xerostomia was a new feature of this update, and the pooled data demonstrated a prevalence of 43% (95% CI = 36% to 50%, I2 = 71%) in patients with COVID-19. Regarding oral mucosal lesions, the most common clinical pattern was aphthous like, followed by herpes-like lesions, candidiasis, glossitis/depapillation/geographic tongue, parotitis, and angular cheilitis. Oral lesions were more frequent in the tongue, lips, and palate, presenting miscellaneous clinical aspects that are more likely to represent coinfections. Therefore, the reanalysis of current evidence suggests the triad xerostomia, taste dysfunction, and oral mucosal lesions as common manifestations in patients with COVID-19. However, these outcomes are under discussion, and more studies will be necessary to confirm their association with direct SARS-CoV-2 infection in the oral cavity.

Leptin decreases apoptosis and promotes the activation of primordial follicles through the phosphatidylinositol-3-kinase/protein kinase B pathway in cultured ovine ovarian tissue.

This study evaluated the effects of leptin on primordial follicle survival and activation after in vitro culture of ovine ovarian tissue and if leptin acts through the phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt) pathway. Ovarian fragments were fixed for histology (fresh control) or cultured for 7 days in control medium (α-MEM+) alone or supplemented with leptin (1, 5, 10, 25 or 50 ng/ml). Follicle morphology, activation and apoptosis were analyzed. Next, the fragments were cultured in the medium that showed the best results in the absence or the presence of the PI3K inhibitor (LY294002), and immunohistostaining of p-Akt protein was assessed. After culture, the percentage of normal follicles decreased (P < 0.05) in all treatments compared with the fresh control. Moreover, control medium and 1 ng/ml leptin had similar (P > 0.05) percentages of normal follicles, which were significantly higher than those in other treatments. However, culture with 1 ng/ml leptin maintained apoptosis similarly (P > 0.05) to that of the fresh control and lower (P < 0.05) than that in α-MEM+. Leptin did not influence follicle activation (P > 0.05) compared with the control medium (α-MEM+). Culture in 1 ng/ml leptin with LY294002 decreased the normal follicles and increased apoptosis, inhibited follicle activation (P < 0.05), and reduced p-Akt immunostaining, compared with the medium containing 1 ng/ml leptin without PI3K inhibitor. In conclusion, leptin at 1 ng/ml reduces apoptosis and promotes the activation of primordial follicles compared with the fresh control after in vitro culture of ovine ovarian tissue possibly through the PI3K/Akt pathway.

Standardization of 223Ra by live-time anticoincidence counting and gamma-ray emission determination.

From a commercial supplier, three independent lots of an aqueous solution containing 223Ra in equilibrium with its deteriorating progeny were considered for standardization, by using live-time anticoincidence counting (LTAC) in the Laboratório Nacional de Metrologia das Radiações Ionizantes (LNMRI) Brazil. The ionization chamber calibration factors were obtained using measurements of independent lots of 223Ra in LTAC considering the absolute method in order to evaluate the constancy and reproducibility of the standardization. The calibration factors of three high-performance well-type ionization chamber systems and four commercial well-type ionization chambers were determined. The LTAC results showed that lots 2 and 3 were 1069.88 and 1097.44 kBq/kg, with corresponding relative standard uncertainties 0.12% and 0.20%, respectively. The spectrometry method results of each lot value were classified as positive by ANOVA hypothesis testing. The emission probabilities relating to the X- and γ-rays in region from 81 to 830 keV ware determined. Hence, LNMRI can provide calibration services for 223Ra.

Oral Manifestations in Patients with COVID-19: A Living Systematic Review.

This living systematic review aims to summarize evidence on the prevalence of oral signs and symptoms in patients with COVID-19. The review was reported per the PRISMA checklist, and the literature search was conducted in 6 databases and in gray literature. Studies published in any language mentioning oral symptoms and signs in patients with COVID-19 were included. The risk of bias was assessed by the Joanna Briggs Institute appraisal tools. The certainty of evidence was evaluated through GRADE assessment. After a 2-step selection, 40 studies were included: 33 cross-sectional and 7 case reports. Overall, 10,228 patients (4,288 males, 5,770 females, and 170 unknown) from 19 countries were assessed. Gustatory impairment was the most common oral manifestation, with a prevalence of 45% (95% CI, 34% to 55%; I2 = 99%). The pooled eligible data for different taste disorders were 38% for dysgeusia and 35% for hypogeusia, while ageusia had a prevalence of 24%. Taste disorders were associated with COVID-19 (odds ratio [OR], 12.68; 95% CI, 6.41 to 25.10; I2 = 63%; P < 0.00001), mild/moderate severity (OR, 2.09; 95% CI, 1.25 to 3.49; I2 = 66%; P = 0.005), and female patients (OR, 1.64; 95% CI, 1.23 to 2.17; I2 = 70%; P = 0.0007). Oral mucosal lesions presented multiple clinical aspects, including white and erythematous plaques, irregular ulcers, small blisters, petechiae, and desquamative gingivitis. Tongue, palate, lips, gingiva, and buccal mucosa were affected. In mild cases, oral mucosal lesions developed before or at the same time as the initial respiratory symptoms; however, in those who required medication and hospitalization, the lesions developed approximately 7 to 24 d after onset symptoms. Therefore, taste disorders may be common symptoms in patients with COVID-19 and should be considered in the scope of the disease's onset and progression. Oral mucosal lesions are more likely to present as coinfections and secondary manifestations with multiple clinical aspects (PROSPERO CRD42020184468).

Magnus-force induced skyrmion-antiskyrmion coupling in inhomogeneous racetrack.

In this paper we investigate a magnetic racetrack consisting of a junction of three materials with different properties. Indeed, this magnetic system is composed by two distinct regions (racetracks) connected by a thin interface: the first region (termed sector 1) has isotropic in-plane magnetic chirality and supports skyrmion (S) excitations while the second (sector 3) has anisotropic chirality and consequently supports antiskyrmions (A). The interface, which would be a third region (sector 2, connecting sectors 1 and 3) located in the central part of the racetrack, is an easy-axis Heisenberg ferromagnetic material. The topological structures S and A are put in motion by applying a spin-polarized current. Under certain conditions, we show that the skyrmion and the antiskyrmion created in their respective sectors are simultaneously impelled to the interface (due to the Magnus force) to apparently become a unique object (a skyrmion-antiskyrmion pair or SAP). After glued by sector 2, the skyrmion and the antiskyrmion move together (as a SAP) along the direction of the applied current. It is also shown that such an engineered racetrack can support a sequence of several SAP structures in motion, forming a current.

Measurement of the absolute gamma emission intensities from the decay of Th-229 in equilibrium with progeny.

There are few long-lived radionuclides yielding high intensity gamma-rays emission with energies ranging from 100 keV to 500 keV that can be applied as radioactive gamma standard to calibrate HPGe detectors. Furthermore, this energy range represents the main emitted energies of the majority of radionuclides used in nuclear medicine. The Brazilian National Laboratory for Ionizing Radiation Metrology (LNMRI/IRD/CNEN) has attempted to identify radionuclides that have the potential to be used as a calibration source due to their long half-life as well as their emission spectrum. Hence, LNMRI promotes standardization studies of gamma-emitting radionuclides that meet these criteria on order to disseminate them. Thorium-229, with its well-defined energies and relatively high intensities, is one such candidate radionuclide for the energy and full-energy peak efficiency calibration of high-purity gamma spectrometers. Thorium-229 was standardized by the method of 4παß(LS)-γ(NaI(Tl)) live timed anticoincidence counting. The emission intensities of gamma-rays associated with the decay of 229Th have been determined by HPGe gamma ray spectrometry with accuracy and precision. The results are in agreement with current literature data.

Prevalência e estudo genético de Mycoplasma gallisepticum e M. synoviae em poedeiras comerciais, na região centro-oeste do estado de São Paulo, Brasil / [Prevalence and genetic study of Mycoplasma gallisepticum and M. synoviae strains from commercial laying hens in the Midwest region of Sao Paulo state, Brazil]

O objetivo deste trabalho foi estudar a prevalência de MG e MS e a filogenia das cepas circulantes, comparando-as com outras já descritas em poedeiras comerciais no Brasil. Foram coletados 140 suabes traqueais de poedeiras comerciais com sinais respiratórios em seis granjas da região centro-oeste de São Paulo. As amostras foram avaliadas por PCR, com posterior sequenciamento e análise filogenética das cepas identificadas. Das 140 amostras, 16,4% foram positivas para MG e 68,6% para MS. Houve diferença significativa nas frequências de MG e MS por granja, segundo o teste G de independência (P<0,05). Todas as cepas identificadas de MG e MS de granjas distintas apresentaram similaridade tanto pela lipoproteína para MG quanto pela região 16s rRNA para MS. Neste estudo, foi possível observar altas prevalências dos agentes estudados, sendo a de MS maior que a de MG. Foi detectada infecção mista por MG e MS em 11,4% das amostras e sabe-se que esses micoplasmas podem agir de forma sinérgica, agravando o quadro respiratório. As cepas circulantes identificadas, pela análise das regiões gênicas da lipoproteína para MG e 16S rRNA para MS, são similares em todas as granjas estudadas.(AU)

The aim of this study was to evaluate the prevalence of MG and MS and the phylogeny of the circulating strains, comparing them with others already described in commercial laying hens from Brazil. A total of 140 tracheal swabs were collected from commercial laying hens with respiratory signs in six farms from the western region of São Paulo state. The samples were analyzed by PCR with subsequent sequencing and phylogenetic analysis of the identified strains. From the 140 samples, 68.6% were positive for MS and 16.4% for MG. There was a significant difference in the frequencies of MG and MS per farm according to G Test of independence (P<0.05). All strains identified as MG and MS from distinct farms presented similarity both by lipoprotein to MG and by 16s rRNA region to MS. In this study, it was possible to observe a high prevalence of MS compared to MG. Mixed MG and MS infection was detected in 11.4% of the samples. These mycoplasmas may act synergistically, worsening the respiratory signs. The circulating strains identified by analysis of the lipoprotein for MG and 16S rRNA for MS are similar on all poultry farms studied.(AU)

Determining the probability of locating peaks using computerized peak-location methods in gamma-ray spectra as a function of the relative peak-area uncertainty.

The probabilities of locating peaks with a high relative peak-area uncertainty were determined empirically with nine types of peak-location software used in laboratories engaged in gamma-ray spectrometry measurements. It was found that it is not possible to locate peaks with a probability of 0.95, when they have a relative peak-area uncertainty in excess of 50%. Locating peaks at these relatively high peak-area uncertainties with a probability greater than 0.95 is only possible in the library-driven mode, where the peak positions are supposed a-priori. The deficiencies of the library-driven mode and the possibilities to improve the probabilities of locating peaks are briefly discussed.

Antiferromagnetic skyrmions overcoming obstacles in a racetrack.

Topological objects interacting with lattice defects is an important topic in condensed matter physics. In this paper, we would like to explore the ballistic trajectory of an antiferromagnetic skyrmion in a racetrack to study processes such as collisions of skyrmions and holes in the magnetic sample. The skyrmion is impelled against the hole-obstacle by means of a spin polarized current. Depending on the skyrmion velocity (associated to the strength of the applied current) and the type of collision (frontal or lateral), it will be captured, scattered or completely destroyed by the hole. In some cases, this obstacle can shift the skyrmion center from a straight line to another one, and it appears as an effective way of manipulating skyrmion trajectories and dynamics.

Murine model of invasive pulmonary Aspergillosis: Follow-up of tissue injury, fungal burden and mortality with distinct elastase production strains.

To study invasive pulmonary Aspergillosis (IPA), we depleted neutrophils in mice using the monoclonal antibody anti-Gr-1/Ly-6G. Immunocompetent and neutropenic mice were infected via intratracheal with conidia of Aspergillus fumigatus clinical isolates, characterized as either higher or lower elastase producers. Neutropenic animals exhibited 100% mortality in 5 days, for both strains, and were observed survival curves overlapped, lungs with angioinvasion, rupture of bronchial and vascular walls, associated with exuberance of conidia filamentation. The immunocompetent animals infected with the lower elastase producer strain presented with upregulated inflammatory processes, and a lack of conidia filamentation in the tissue. The fungal burden in the lungs was not different in the immunocompetent and neutropenic groups. These findings confirm the protective role of neutrophils against A. fumigatus and suggest that the fungal elastinolytic activity is not a critical virulence factor but may be involved in tissue injury.

Prevalência de hanseníase em São Luís–Maranhão entre os anos de2013 a 2015 / Prevalence of leprosy in São Luís-Maranhão from 2013 to 2015

Objetivo: analisar e representar, espacialmente, a evolução da distribuição geográfica dasocorrências de Hanseníase no Maranhão entre os anos de 2013 a 2015, utilizando técnicas degeoprocessamento. Método: realizou-se análise, utilizando mapas e tabelas temáticas, com base nosregistros do Sistema de Informação de Agravos de Notificação. Resultados: foram identificados 1.879casos, somados entre 219 bairros residenciais. Para o ano de 2013, o distrito mais afetado foi oTirirical; em 2014, aumentou a prevalência nos Distritos de Bequimão e Coroadinho e em 2015, houveuma redução de prevalências nos distritos de Tirirical Cohab, Coroadinho e Itaqui Bacanga.Conclusão: apesar de algumas localidades estudadas terem apresentado uma diminuição daprevalência entre 2013 e 2014, de 2014 a 2015 houve um aumento na quantidade de casos. O estudode prevalências possibilitou essa identificação de casos, podendo ser observada a imprescindibilidadede subsidiar estratégias de controle.

Objective: to analyze and spatially represent the evolution of the geographic distribution ofoccurrences of Leprosy in Maranhão between the years 2013 to 2015 using geoprocessing techniques.Method: the analysis was performed using maps and thematic tables, based on the records of theNotifiable Diseases Information System. Results: 1.879 cases were identified, among 219 residentialdistricts. For the year 2013, the district most affected was Tirirical; in 2014, increased prevalencein the Districts of Bequimão and Coroadinho and in 2015, there was a reduction of prevalences in thedistricts of Tirirical Cohab, Coroadinho and Itaqui Bacanga. Conclusion: although some localitiesstudied showed decrease in their prevalence between 2013 and 2014; there was increase in thenumber of cases from 2014 to 2015. The prevalence study made it possible to identify cases, and itis possible to observe the necessity of subsidizing control strategies.

Temporal expression of pluripotency-associated transcription factors in sheep and cattle preimplantation embryos.

SummaryPluripotency-associated transcription factors (PATFs) modulate gene expression during early mammalian embryogenesis. Despite a strong understanding of PATFs during mouse embryogenesis, limited progress has been made in ruminants. This work aimed to describe the temporal expression of eight PATFs during both sheep and cattle preimplantation development. Transcript availability of PATFs was evaluated by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) in eggs, cleavage-stage embryos, morulae, and blastocysts. Transcripts of five genes were detected in all developmental stages of both species (KLF5, OCT4, RONIN, ZFP281, and ZFX). Furthermore, CMYC was detected in all cattle samples but was found from cleavage-stage onwards in sheep. In contrast, NR0B1 was detected in all sheep samples but was not detected in cattle morulae. GLIS1 displayed the most significant variation in temporal expression between species, as this PATF was only detected in cattle eggs and sheep cleavage-stage embryos and blastocysts. In silico analysis suggested that cattle and sheep PATFs share similar size, isometric point and molecular weight. A phenetic analysis showed two patterns of PATF clustering between cattle and sheep, among several mammalian species. In conclusion, the temporal expression of pluripotency-associated transcription factors differs between sheep and cattle, suggesting species-specific regulation during preimplantation development.

Effect of pre-exercise carbohydrate availability on fat oxidation and energy expenditure after a high-intensity exercise.

The aim of this study was to test the hypothesis that reduced pre-exercise carbohydrate (CHO) availability potentiates fat oxidation after an exhaustive high-intensity exercise bout. Eight physically active men underwent a high-intensity exercise (∼95% V̇O2max) until exhaustion under low or high pre-exercise CHO availability. The protocol to manipulate pre-exercise CHO availability consisted of a 90-min cycling bout at ∼70% V̇O2max + 6 × 1-min at 125% V̇O2max with 1-min rest, followed by 48 h under a low- (10% CHO, low-CHO availability) or high-CHO diet (80% CHO, high-CHO availability). Time to exhaustion was shorter and energy expenditure (EE) lower during the high-intensity exercise in low- compared to high-CHO availability (8.6±0.8 and 11.4±1.6 min, and 499±209 and 677±343 kJ, respectively, P<0.05). Post-exercise EE was similar between low- and high-CHO availability (425±147 and 348±54 kJ, respectively, P>0.05), but post-exercise fat oxidation was significantly higher (P<0.05) in low- (7,830±1,864 mg) than in high-CHO availability (6,264±1,763 mg). The total EE (i.e., exercise EE plus post-exercise EE) was similar between low- and high-CHO availability (924±264 and 1,026±340 kJ, respectively, P>0.05). These results suggest that a single bout of high-intensity exercise performed under low-CHO availability increased post-exercise fat oxidation, and even with shorter exercise duration, both post-exercise EE and total EE were not impaired.

Rapid and accurate assessment of the activity measurements in Brazilian hospitals and clinics.

Traceability in Nuclear Medicine Service (NMS) measurements was checked by the Institute of Radioprotection and Dosimetry (IRD) through the Institute of Energy and Nuclear Research (IPEN). In 2016, IRD ran an intercomparison program and invited Brazilian NMS authorized to administer 131I to patients. Sources of 131I were distributed to 33 NMSs. Three other sources from the same solution were sent to IRD, after measurement at IPEN. These sources were calibrated in the IRD reference system. A correction factor of 1.013 was obtained. Ninety percent of the NMS comparisons results are within ±10% of the National Laboratory of Metrology of Ionizing Radiation (LNMRI) value, the Brazilian legal requirement.

134Cs activity standardization by 4πß(LS)-γ(NaI-Tl) anticoincidence counting and submission to international reference system.

From a commercial supplier a solution containing 134Cs has been standardized at National Laboratory for Ionizing Radiation Metrology (LNMRI) for the first time using three Liquid scintillation based measurement. These measurement methods are 4πß-γ live-timed anticoincidence counting, 4πß-γ coincidence counting and 3H-standard efficiency tracing with the CNET methods. The results obtained by anticoincidence counting was adopted as reference value and its combined uncertainty was 0.38%. The agreement of this reference value with coincidence counting and CNET methods were 0.39% and 0.34% respectively and were in consistency with each uncertainty method. The weighted mean results coincidence counting and CNET methods are also in close agreement 0.03% with anticoincidence counting method and meets the requirement of primary and national standard. This standardization was made in order to reduce the uncertainty in 134Cs measurement in Brazil and also following a request made by Bureau International des Poids and Mesures for new submission to International Reference System. The LNMRI last submission was made in 1987. Therefore from a 134Cs master solution a NIST ampoules was prepared and LNMRI/IRD submitted it to the International Reference System, Bureau International of Poids and Measures (SIR/BIPM). In this paper will be analyzed the LNMRI measurement and performance each measurement methods and also take into account the reference value of KCDB, we determined also the 134Cs gamma emission probabilities of main energy.

Aerophagia in adolescents is associated with exposure to adverse life events and psychological maladjustment.

BACKGROUND: Aerophagia is a common childhood functional gastrointestinal disorder. We studied the association between adverse life events (ALEs), psychological maladjustment, somatization, and aerophagia (AP) in adolescents. We also assessed the impact of AP on their health-related quality of life (HRQoL). METHODS: A cross-sectional survey was conducted on 2500 subjects of 13-18 years in 8 randomly selected schools in Sri Lanka. Translated, validated, and self-administered questionnaires were used to collect data. Aerophagia was diagnosed using Rome III criteria. KEY RESULTS: A total of 2453 questionnaires were analyzed (males 1200 [48.9%], mean age 14.8 years, SD 1.6 years). Of them, 371 adolescents had AP (15.1%). Aerophagia was associated with exposure to physical abuse (20.4% vs. 12.7% in controls, P < .0001), emotional abuse (20.3% vs. 8.2% in controls, P < .0001), and other ALEs (22% vs. 10.2% in controls, P < .001). One hundred and ninety (51.2%) adolescents with AP and 775 (37.2%) controls had a personality score above the international cutoff value of 105, indicating psychological maladjustment (odds ratio 1.77, 95% confidence interval 1.42-2.21, P < .0001). Those with AP had higher somatization (16.4 vs. 8.9) and lower overall HRQoL scores (77.0 vs. 85.1, P < .0001). HRQoL scores of adolescents with AP were lower in all domains, namely, physical (80.6 vs. 86.9), emotional (69.1 vs. 80.3), social (83.8 vs. 90.5), and school (72.6 vs. 82.5) functioning (P < .0001). CONCLUSIONS AND INFERENCES: Aerophagia was associated with exposure to ALEs and psychological maladjustment. Affected teenagers suffer from more somatic symptoms and has a poor HRQoL.

Effect of RRR-α-tocopherol supplementation on serum of breastfeeding women up to 60 days after delivery: a randomised controlled trial.

BACKGROUND: Maternal supplementation is a viable strategy to combat vitamin E deficiency in newborns, although a protocol for maternal vitamin E supplementation has not been defined. The present study assessed the effect of maternal supplementation in a single dose on the serum of postpartum women up to 60 days after delivery. METHODOLOGY: Fifty healthy breastfeeding women were recruited at two maternity hospitals both located in Natal, RN, Brazil. The participants were randomly allocated to a control group and a treatment group in a 1 : 1 ratio. Serum was collected 1, 20, 30 and 60 days after delivery. Immediately after the first collection, the treatment group received a single dose of 400 IU of RRR-α-tocopherol. α-Tocopherol was quantified by high-performance liquid chromatography. The usual dietary vitamin E intake was determined using four 24-h recalls, and intake adequacy was assessed based on the estimated average requirements for lactating women (16 mg day-1 ). RESULTS: The mean dietary vitamin E intakes of the both groups were similar (P > 0.05) and inadequate. The serum levels of α-tocopherol assessed at 1, 20, 30 and 60 days indicated adequate vitamin E status in both the control group (1194.6, 907.7, 910 and 748.6 µg dL-1 , respectively) and treatment group (1183.7, 956.0, 935.9 and 766.4 µg dL-1 , respectively). The comparison at each day showed no difference between treatments (P > 0.05). CONCLUSIONS: A single vitamin E supplement did not change the mean serum level of α-tocopherol in breastfeeding women; thus, it does not improve their vitamin E status in the first 60 days after delivery.

Effects of second neighbor interactions on skyrmion lattices in chiral magnets.

In this paper we investigate the influences of the second neighbor interactions on a skyrmion lattice in two-dimensional chiral magnets. Such a system contains the exchange and the Dzyaloshinskii-Moriya for the spin interactions and therefore, we analyse three situations: firstly, the second neighbor interaction is present only in the exchange coupling; secondly, it is present only in the Dzyaloshinskii-Moriya coupling. Finally, the second neighbor interactions are present in both exchange and Dzyaloshinskii-Moriya couplings. We show that such effects cause important modifications to the helical and skyrmion phases when an external magnetic field is applied.