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Alzheimer’s disease (AD) and dementia has emerged as a significant societal issue and a global priority. The prevalence of dementia is rising more rapidly in low and middle income countries (LMIC) than in high income countries. Yet, knowledge of dementia risk factors is dominated by research from high income countries (HIC), which cannot be readily translated to LMIC. Latin American countries (LAC) have unique challenges related to dementia, including rapid aging population, high admixture degree and risk factors profile, which influence the prevalence and presentation of dementia. Several epidemiological studies during the past decade have shown a rapid increase of dementia in LAC, but the impact of genetic, protective and risk factors remain poorly understood. This research session will feature a series of short and engaging talks about new trends of dementia in the region and will answer key questions regarding dementia determinants and consequences in Hispanic populations. Participants will be first introduced to the aging process in LAC, prevalence and incidence of dementia within the region. The second presentation will report on genetics of Alzheimer disease in Hispanic populations. The third presenter will discuss the complexities of dementia multimorbidity and the impact of neuropsychiatric symptoms. The fourth presenter will discuss about Nationals and Regional Strategies to address dementia and reflects on recommendations and future directions for the region. All presentations will be based on findings from multiple research projects across the region. Furthermore, presenters will extended comparison to Non-Hispanics whites and Hispanics populations living in US, which allows cross countries/society comparisons. Overall, new information about dementia will be shared with the audience. Attendees will be able to identify the unique genetic and social determinants that drive AD in LAC. Recommendations will be given for preventive strategies tailored to LMIC. The findings to be shared will be essential for building evidence-based interventions that achieve the goals of the National Plan to Address Alzheimer’s Disease.
The study described in this Research Communication investigated the genotypic and phenotypic profiles of resistance to beta-lactams and other antimicrobials in non-aureus Staphylococci (NAS) isolated from buffalo, goat and sheep mastitis in the Northeast region of Brazil. A total of 190 isolates were analyzed and 42.3, 43.9 and 23.6% of them were positive for blaZ gene in buffalo, goat and sheep, respectively. Regarding the animal groups, in goats, amoxicillin was the antimicrobial with highest resistance index (72.7%), followed by penicillin G in buffaloes (51.9%) and ampicillin in sheep (43.1%). With regard to multiple antimicrobial resistance, 30.8% of NAS isolates from buffalo milk samples, 25.8% from goats and 25.0% from sheep presented multidrug-resistance. In the minimum inhibitory concentration (MIC) technique, amoxicillin MIC50 and MIC90 were 64 and 128 μg/ml, respectively, among isolates of the three animal species. In conclusion, high rates of resistance to beta-lactams are presented among NAS isolated from mastitis cases in buffaloes, goats and sheep in Northeast region of Brazil. These results provide an alert to animal and human health researchers, suggesting that the frequency of NAS needs to be reduced because they carry resistance genes which might increase the existing levels of antimicrobial resistance.
This study assessed the in vitro anthelmintic (AH) activity of methanol and acetone:water leaf extracts from Annona squamosa, A. muricata and A. reticulata against Haemonchus contortus eggs. The egg hatch test was used to determine the effective concentrations required to inhibit 50% of eggs hatching (EC50). The role of polyphenols on AH activity was measured through bioassays with and without polyvinylpolypyrrolidone (PVPP). Methanolic extracts mainly caused the death of eggs at the morula stage (ovicidal activity). Meanwhile, acetone:water extracts caused egg-hatching failure of developed larvae (larvae failing eclosion (LFE) activity). The lowest EC50 values against H. contortus eggs were observed for the methanolic extracts from A. reticulata and A. muricata (274.2 and 382.9 µg/ml, respectively). From the six extracts evaluated, the methanolic extracts of A. muricata, A. reticulata and A. squamosa showed the highest ovicidal activity, resulting in 98.9%, 92.8% and 95.1% egg mortality, respectively. When the methanolic extract of A. squamosa was incubated with PVPP, its AH activity increased. Similarly, when acetone:water extracts of A. muriata and A. reticulata were incubated with PVPP, their LFE activity increased. Alkaloids were only evident in methanolic extracts, irrespective of PVPP incubation. The presence of acetogenins was not observed. In conclusion, methanolic extracts obtained from leaves of A. muricata, A. reticulata and A. squamosa showed ovicidal activity affecting the morula of H. contortus eggs, with minor LFE activity. Meanwhile, acetone:water extracts showed mostly LFE activity, with a lower proportion of ovicidal activity.
Recent excavations at the Early–Middle Formative period site of Altica in the southern piedmont of the Teotihuacan Valley, Mexico, provide evidence for early agriculture and plant use in a rural community in the northern Basin of Mexico. In the Basin of Mexico, settled agricultural communities were present in the southern sector of the region from at least 1200 cal b.c. Initial expansion into the semiarid northern sector of the Basin, however, appears to have taken place towards the end of the Early Formative, during the transition to the Middle Formative when agricultural economies based on maize cultivation became firmly established, setting the scene for increased population density and concomitant social complexity.
Altica is currently the only community in the Teotihuacan Valley spanning this transitional period that has survived in the face of intensive changes in land use over the last three millennia. Macro- and microbotanical evidence recovered from radiocarbon-dated excavated contexts at Altica provide evidence for maize cultivation and suggest a subsistence economy in transition, prior to the establishment of intensive dependence upon a broader range of domesticated and cultivated plants.
Galaxy clusters are excellent targets for high energy astrophysics with gamma rays. Not only they may host active galaxies, but they are often expected to provide signatures of accelerations of electrons and protons to PeV energies. Furthermore, according to ΛCDM scenario, they should be embedded in an extremely massive dark matter halo, the largest halo expected. In this report, we summarize the recently published MAGIC lower limits on the decaying dark matter lifetime using 202 h of selected high quality data taken on the Perseus galaxy cluster, in a 5-year long campaign.
The in vitro larvicidal and in vivo anthelmintic effects of Oxalis tetraphylla hydroalcoholic extract (HE), against Haemonchus contortus in experimentally infected lambs, were assessed. We used a microtitration plate method, comprising the following two stages. Stage 1: 20 μl of water containing 200 sheathed H. contortus infective larvae (ShHcl) were deposited in every well of three series; then, the series 2 and 3 wells were treated with 80 μl 1% ivermectin and O. tetraphylla HE at 20 mg/ml, respectively. Stage 2: the same procedure was performed replacing the ShHcl with exsheathed larvae (ExShHcl). Evaluations were performed after 24 and 48 h. The total numbers of dead and live larvae were counted. A second experiment evaluated the reduction in nematode egg populations in the faeces of lambs treated orally with the O. tetraphylla HE. The 27 lambs used were divided into Groups 1, 2 and 3 (n = 9), which were administered water (positive control), levamisole 1 m (7.5 mg/kg body weight (BW), as a unique dose) and O. tetraphylla HE (20 mg/kg BW), respectively. The plant HE was administered daily for 8 days. The in vitro assay showed 80.9% and 86.5% larval mortality of ShHcl after 24 and 48 h, respectively, while the corresponding mortality values for ExShHcl were 97 and 99%, respectively. The in vivo assay showed variability in the eggs/gram of faeces (epg) values; however, at the end of the trial, the average reduction in the epg values of the O. tetraphylla HE group was 45.6% (P < 0.05). Oxalis tetraphylla HE contains compounds that belong to the flavonol group with anthelmintic activity.
Clinical manifestations of acute bronchiolitis (AB) vary from minimal disease to severe respiratory failure. The response to respiratory viral infections is possibly influenced by genetic polymorphisms linked to the regulation of the inflammatory response. In the present study, we investigated whether interleukin-8 (IL-8) and interleukin-17 (IL-17) genetic variants are associated with the severity of AB. A group of Brazilian infants hospitalized with AB and a control group (infants with no or mild AB, without hospitalization) were genotyped for four IL-8/IL-17 variations. For replication, we studied an Argentinean population sample of infants with mild and severe AB. IL-8 polymorphism (rs 2227543) and IL-17 (rs2275913) variants showed significant associations with the severity of AB. The effect of the IL-8 variation could be replicated in the Argentinean sample. This finding suggests that IL-8 variations may influence the severity of AB in young infants. Further genetic association studies in low- or middle-income populations are necessary with the aim of expanding knowledge in this area.
Two groups of six Haemonchus contortus infected Saint Croix lambs each received different diets for 11 weeks: control group, commercial food, molasses and lucerne hay; and treated group, nutritional pellets (NPs) containing Duddingtonia flagrans at 2 × 106 chlamydospores/kg body weight (BW), sorghum and lucerne hay. Mean BW gain (BWG), body condition score (BCS) and packed cell volume (PCV) and also eggs/g of faeces (EPG) and recovered L3 were compared using a repeated measures across time model. Groups had similar BWG (control 139.7 ± 0.035 g/day and treated 167.7 ± 0.041 g/day), BCS (control 3.6 ± 0.39 and treated 3.4 ± 0.46) and PCV (control 32.5 ± 1.68% and treated 30.0 ± 1.68%). The mean EPG of the control group was 1215 ± 1040 and in the treated group it was 2097.91 ± 2050. No reduction in larval population was observed during weeks 2 and 3. The greatest larval population reduction in the faeces of treated lambs was observed during the first week (70.5%) and from weeks 6 to 11, with a mean value close to 70% (P < 0.05). In general, both experimental groups showed a similar feed conversion. It was concluded that both diets resulted in similar lamb growth, PCV, BCS and H. contortus EPG. However, NP consumption significantly reduced the H. contortus L3 population in lamb faeces.
Powders of La2O3 were mixed with mechanical ball-milling
technique (MA) adding TiO2, to improve the electrochemical
performance as a storage material. Microstructures, morphologies and
electrochemical results were investigated using TEM, X-ray diffraction (XRD),
Cyclic Voltammetry and Potentiodynamic studies. Results showed that, the samples
with TiO2 content affected the capacity of response. The alloys
exhibit a superior capacity and stability adding TiO2. The milling
ball to powder weight ratio was kept 5 to 1 for all experimental runs. Milling
intervals were 0, 2 and 4 hrs; using alternate cycles of 30 minutes milling and
30 min resting. The nanostructure TiO2 powder, improves the samples
to design a better electrode. TiO2 has significant influence on
electrochemical performance of electrodes. Electrochemical experiments were
performed on ACM Instruments Gill AC and a typical three electrode setup was
constructed to measure the electrochemical properties of the working electrode.
Here, platinum was used as the counter electrode and calomel was used as the
reference electrode. Structures of the samples were analyzed by digital image
Were synthesized four new hybrid hardener agents type amino tertiary functionalized with allyl groups from : l, 6-Hexanediamine, Diethylenetriamine, Trietilentriamine and Tris (2-aminoethyl) amine, using the basic nucleophilic substitution mechanism, replacing bromide by amino tertiary group in the presence of tetrabutylammonium bromide as phase transfer agent, producing allyl amine corresponding: ALA-4, ALA-5, ALA-6 and TRIS respectively, which were evaluated as a hardening of epoxy resin DGEBA through photopolymerization process by UV ligth curing, adding a 10, 20 and 40% molar percentage of hybrid materials and the thiol corresponding to carry out the thiol-ene reaction (TMP TMP, PTKMP) with DMPA as initiator. The resinic materials obtained, were evaluated by the technique of dynamic mechanical analysis (DMA) at a heating rate of 5° C/min in a range from - 50° C to 150° C in nitrogen atmosphere. The formulations with hybrid hardening agent ALA 4- 20% -PTKMP and TRIS 10% -PTKMP were the materials with modulus 2289, 2971 Mpa and tgs of 102,103°C, respectively.
The highlight of this work is the synthesis of copper sulfide nanocrystals by a simple one-pot colloidal process, and the study of its electrochemical, electrical and morphological properties. Nanocrystals of Cu1.8S of about 15-30 nm were obtained at a temperature of 240°C under an argon atmosphere. The colloidal solution of the nanocrystals was analyzed by cyclic voltammetry. Agreeing to the values of EOx and ERedvs. SCE, and the average of three samples the HOMO and LUMO levels are 6.16 and 4.27 eV, respectively, the calculated HOMO – LUMO (Eg) is 1.89 eV. The Eg value, differs of that value obtained from Kubelka-Munk equation (1.7 eV). The photocurrent vs. time results showed that the Cu1.8S/Cu junction is photosensitive and could be used as absorbing material. The morphology and the topography of the film were analyzed by SEM and AFM techniques. Irregular agglomeration of nanocrystals was observed and a roughness of about 194 nm.
Lithium ion batteries are becoming more important because of their high energy density and design flexibility. The capacity of these batteries is usually cathode limited; so, it follows that increasing the capacity of the cathode is essential to raise the performance of such batteries. In this work, fractal dimension study is used to understand the behavior of a Li2TiO3 made by mechanical milling, as a way to improve their uses in energy storage. Digital image analysis allows the study of fractal dimension; X-ray, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) analysis were used to analyze changes on the surface of samples from the current results the distinctive characteristics of the surfaces for each sample may be obtained, making it possible to predict a future behavior of the samples. MATLAB software FRACLAB 2.03 developed by INRIA was used as a tool.
The study evaluated the effect of storage time and conditions of nutritional pellets (NP) containing Duddingtonia flagrans chlamydospores on its in vitro trapping ability against Haemonchus contortus L3 larvae. The treated batch (200 NP) contained 4 × 106 chlamydospores of the FTH0-8 strain, whereas the control batch (200 NP) was produced without spores. Both NP batches were exposed to four experimental storage conditions: (T1) shelves (indoors); (T2) refrigeration (4°C); (T3) outdoors under a roof; and (T4) 100% outdoors. Each group comprised 48 NP with spores and 48 NP without spores (control). The ability of D. flagrans spores to trap H. contortus L3 larvae was evaluated for 8 weeks for each storage condition. For that purpose, six randomly selected NP with spores were compared to their respective control NP. Each NP was individually crushed. The crushed material (1 g) was placed on the surface of a 2% water agar plate with 200 H. contortus L3 larvae. Plates were sealed and were incubated at room temperature for 8 days. The whole content of every plate was transferred to a Baermann apparatus to recover the remaining larvae. There was a clear larval reduction in the NP with spores, compared to the respective control NP in the four storage conditions (P< 0.05). The mean reductions ( ± SEM) of the storage conditions were 67 ± 4.9 (T2), 77 ± 6.1 (T1), 81.5 ± 3.8 (T4) and 82.1 ± 2.5 (T3). Larval reductions were similar at all times and were not affected by storage conditions or storage time (R2< 0.2; P>0.05). The long-term shelf-life of the chlamydospores in the NP suggests that this spore dosage technology is a viable option.
This study explored the predictive power of effortful control (EC) on empathy, academic performance, and social competence in adolescents. We obtained self-report measures of EC and dispositional empathy in 359 students (197 girls and 162 boys) aged between 12 and 14 years. Each student provided information about the prosocial behavior of the rest of his/her classmates and completed a sociogram. At the end of the school year, we calculated the mean grade of each student and the teacher responsible for each class completed a questionnaire on the academic skills of his/her students. The study confirmed the existence of a structural equation model (SEM) in which EC directly predicted academic performance and social competence. Additionally, empathic concern partially mediated the effect of EC on social competence. Finally, social competence significantly predicted academic performance. The article discusses the practical applications of the model proposed.
The goal of this study was to analyze the recidivism rate in minor offenders to whom a minimum intervention measure was applied after their first felony or misdemeanor, and to determine the variables associated with recidivism. The sample was made up of 154 minors from the province of Santa Cruz of Tenerife (Canary Islands, Spain). The information was collected from the database of the Minors' Court. The recidivism rate depends on the measure imposed, ranging between 14 and 40.6%. The degree of agreement between the Technical Team's proposal and the court decision was 70%. With regard to the variables associated with recidivism, a model was obtained through logistic regression that correctly classified 83.7% of the cases, and was made up of the variables perception of parenting problems, intervention of social services, and social isolation.
This research includes results on the corrosion performance of reinforcing steel in cement-based mortar (pH ~ 13) when cactus (Opuntia Ficus Indica –Nopal) slime was used as an addition. The cactus slime addition was mixed at different concentrations by mixing water mass (0%, 1.5%, 4%, 8%, 42%, and 95%). Half-cell potentials and LPR measurements were performed at different time periods to characterize the possible corrosion inhibiting effect of the cactus additions tested. Results showed good corrosion inhibiting effect of Nopal slime on reinforcing steel, in all tested solutions, when chloride ions were present. The addition of such cactus led to an apparent formation of a denser and more packed oxide/hydroxide surface layer on the steel surface that decreased corrosion activity. This oxide/hydroxide layer growth was confirmed from microscopic evaluation of the metal surface layer performed at the end of the research program. The preliminary findings suggest that adding Nopal slime in concentrations between 4% and 8%, by water mass, might be suitable for durability enhancing applications in cement-based mortar.
Congenital cardiac diseases are the most frequent congenital malformations. In adult patients, the mineralisation of the aorta due to cardiovascular disease is very common, but vascular mineralisation in paediatric cardiopathies is a topic less studied. This study shows that children with a complex congenital cardiopathy show a high degree of vascular mineralisation in the ascending aorta. This can be part of the cardiac failure pathophysiology due to congenital cardiopathies.
The aim of this study was to determine the presence and degree of vascular mineralisation in samples of the ascending and descending aorta of children with complex congenital cardiopathies.
We conducted a cross-sectional study.
We obtained 34 vascular tissues from the autopsies of 17 children with congenital cardiac disease.
We used a scanning electron microscope with an energy-dispersive X-ray spectroscopy in order to analyse the vascular tissues.
The amount of minerals was two times higher in the ascending aorta than in the descending aorta of children with congenital cardiac disease.
The study provides evidence that vascular mineralisation can start at an early age, and that it is higher in the ascending aorta than in the descending aorta.
The fortune jack Seriola peruana is reported in the southern Gulf of California for the first time, further north than its usual area of occurrence in the tropical eastern Pacific. Meristics and morphometric data of the specimen are given.
José de acosta (1539–1600) was a Jesuit who served as a missionary in Peru from 1571 to 1587. His Historia natural y moral de las Indias (1590) was an extremely influential description of the history, geography, and ethnography of the New World and was translated into English by Edward Grimstone in 1604. Like Las Casas, he opposed the oppression and over-taxation of the Native Americans and had several audiences with King Philip II, who favored his views over those of Sepúlveda.
That the incapacity of the Indians proceeds not from nature but from upbringing and custom
I shall add something that I think of the highest importance. In every respect, the Indians' slowness of mind and savagery are not caused by factors of birth, origin, or native climate but by their daily upbringing, and by habits not greatly dissimilar from the life of beasts. I have indeed been convinced of this for a long time, and am now unshakeably assured by hard facts. If one considers the matter soundly, upbringing generally plays a far larger part in human intelligence than birth. Ancestry and country admittedly have considerable force: corroborating the poet Epimenides, the Apostle Paul wrote, “The Cretians are alway liars, evil beasts, slow bellies” (Titus 1:12), as though nationality contributed much to perversity of customs. The observation of another poet, however, is also widely known: “You would think him a Boeotian, born where the air is dense” (Horace, Epistles 2.1.244).