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Use of Patagonia's forests by hunter-gatherers remains relatively poorly understood. Regional archaeological records indicate initial forest colonization during the middle Holocene, infrequent use until late prehistory, and, even then, fairly sparse occupation, likely in conjunction with use of the adjacent steppe. Recent excavations at Río Ibáñez-6 West in Aysén, Chile, provide a new perspective for understanding the prehistoric use of Patagonian forests, particularly regarding timing of the initial occupation and the potential for development of a forest-specific adaptation. We provide chronological, lithic, archaeofaunal, and macrobotanical data that show use of the Ibáñez River valley at least a millennium earlier than previously documented. These data indicate increased dietary breadth in late prehistory, supporting the established hypothesis that the valley became a closed system at that time. From our data we develop hypotheses regarding prehistoric forest use in Aysén that have implications for the broader understanding of the suitability of the forest for prehistoric human foragers.
We set out to document the diversity and distribution of bryophytes in Admiralty Bay and thereby enable the identification of patterns in local diversity and their possible drivers. Combining data extracted from different sources and recent collections, we documented the presence of 63 species. Similarity analyses of moss species diversity in relation to underlying geology and ornithogenic influence identified an identical cophenetic correlation coefficient of 0.744 for both factors. The Sørensen index was < 0.6, indicating that the groups share < 60% of the species recorded. The data showed that the selected filters (ornithogenic soils, non-ornithogenic soils and different geological extracts) did not underlie consistent species groupings, and we conclude that other environmental and topographical factors are likely to be responsible for shaping the moss community structure in Admiralty Bay. To enable effective management of Antarctic Specially Managed Area (ASMA) No. 1 and Antarctic Specially Protected Area (ASPA) No. 128, robust assessments of the local ecosystem and biodiversity are necessary to assist in the decision-making processes mandated under the Antarctic Treaty System, one of whose founding principles is the preservation of the Antarctic ecosystem.
From a systematic review framework, we assessed the preclinical evidence on the effectiveness of drug combinations for visceral leishmaniasis (VL) treatment. Research protocol was based on the PRISMA guideline. Research records were identified from Medline, Scopus and Web of Science. Animal models, infection and treatment protocols, parasitological and immunological outcomes were analysed. The SYRCLE's (SYstematic Review Center for Laboratory Animal Experimentation) toll was used to evaluate the risk of bias in all studies reviewed. Fourteen papers using mice, hamster and dogs were identified. Leishmania donovani was frequently used to induce VL, which was treated with 23 drugs in 40 different combinations. Most combinations allowed to reduce the effective dose, cost and time of treatment, in addition to improving the parasitological control of Leishmania spp. The benefits achieved from drug combinations were associated with an increased drug's half-life, direct parasitic toxicity and improved immune defences in infected hosts. Selection, performance and detection bias were the main limitations identified. Current evidence indicates that combination chemotherapy, especially those based on classical drugs (miltefosine, amphotericin B antimony-based compounds) and new drugs (CAL-101, PAM3Cys, tufisin and DB766), develops additive or synergistic interactions, which trigger trypanocidal and immunomodulatory effects associated with reduced parasite load, organ damage and better cure rates in VL.
To estimate the prevalence of vitamin A deficiency (VAD) in children and associated risk factors.
Design:
Analysis of data from a cross-sectional multicentre study performed in the primary care units of the municipalities from January to June 2015. The children’s legal guardians answered a socio-economic questionnaire, and the children’s blood samples were obtained by venipuncture. Plasma retinol was determined by HPLC. Plasma retinol values of <0·70 μmol/l were considered VDA. Poisson multiple regression with robust variance was used. Values of P < 0·05 were considered significant. The data were analysed in the SPSS software, 21.0.
Setting:
Forty-eight poorest municipalities in the South Region of Brazil.
Participants:
Children (n 1503) aged 12–59 months.
Results:
The prevalence of VAD in the sample was 1·9 % (95 % CI (0·5, 6·8)). The following risk factors were associated with the outcome in the final explanatory model: family received Bolsa Familia program benefits (PR = 3·19; 95 % CI (1·69, 6·02)), child was not being breastfed (PR = 5·22; 95 % CI (1·68, 16·18)) and stunting (PR = 4·75; 95 % CI (2·10, 10·73)).
Conclusions:
VAD did not represent a public health problem for children living in socio-economically vulnerable municipalities in the South Region of Brazil, suggesting a new panorama of this nutritional deficiency even in regions of low socio-economic conditions in these three states. Thus, in view of the current nutritional transition scenario, it is necessary to continuously monitor and improve public policies related to vitamin A supplementation in the country.
The distribution of the Vulnerable West Indian manatee Trichechus manatus is influenced by physical and environmental factors such as water salinity, temperature and depth, freshwater supply and the availability of food resources. In Brazil, information on the habitat use of this species is insufficient for effective conservation. Here, we monitored manatees that had been found stranded as calves, rehabilitated in captivity and subsequently released, to identify their home ranges and examine their adaptation to life in the wild. The study, which involved monitoring six manatees using satellite and VHF telemetry systems, was conducted during 2016–2019 in the states of Paraíba, Sergipe and Bahia in north-eastern Brazil. Home range size of individuals was 2.56–42.07 km2 and all fidelity sites (areas used most frequently) were within protected areas. The longest distance travelled from the coastline upriver was 14.24 km and the longest distance offshore was 0.93 km. There were no significant differences in home range data between the dry and rainy seasons, but there was significant difference between the sexes, with males travelling across larger areas than females. All but one of the six individuals met the majority of indicators established in the Brazilian Manatee Reintroduction Protocol, and thus were considered to have successfully adapted to the wild. Our study provides information on patterns of habitat use and areas intensely used by manatees, which can assist protected area managers in defining priority areas for manatee conservation in Brazil.
In Brazil, national estimates of childhood malnutrition have not been updated since 2006. The use of health information systems is an important complementary data source for analysing time trends on health and nutrition. This study aimed to examine temporal trends and socio-demographic inequalities in the prevalence of malnutrition in children attending primary health care services between 2009 and 2017.
Design:
Time trends study based on data from Brazil’s Food and Nutrition Surveillance System. Malnutrition prevalence (stunting, wasting, overweight and double burden) was annually estimated by socio-demographic variables. Prais–Winsten regression models were used to analyse time trends. Annual percent change (APC) and 95 % CI were calculated.
Setting:
Primary health care services, Brazil.
Participants:
Children under 5 years old.
Results:
In total, 15,239,753 children were included. An increase in the prevalence of overweight (APC = 3·4 %; P = 0·015) and a decline in the prevalence of wasting (–6·2 %; P = 0·002) were observed. The prevalence of stunting (–3·2 %, P = 0·359) and double burden (–1·4 %, P = 0·630) had discrete and non-significant reductions. Despite the significant reduction in the prevalence of undernutrition among children in the most vulnerable subgroups (black, conditional cash transfer’s recipients and residents of poorest and less developed areas), high prevalence of stunting and wasting persist alongside a disproportionate increase in the prevalence of overweight in these groups.
Conclusions:
The observed pattern in stunting (high and persistent prevalence) and increase in overweight elucidate setbacks in advances already observed in previous periods and stresses the need for social and political strategies to address multiple forms of malnutrition.
Congenital transmission of Chagas disease plays an important role in endemic countries because it is not a diagnosis that is encountered frequently in prenatal care. Due to limited information regarding congenital transmission of Trypanosoma cruzi in Mexico, the present study aimed to investigate protozoan infectivity and modulation of immune responses in human placental explants infected with T. cruzi Ia Mexican strains. The Inc-5 strain showed increased infectivity and modulated IL-1β, IL-10 and TLR-4, decreasing their expression after 24 h of infection. Both strains (Inc-5 and Ninoa) stimulated the production of TNF-α and decreased IL-6 levels 96 h after infection. An important detachment of the syncytiotrophoblast caused by infection with T. cruzi was observed after 24 h of infection. In this study, ex vivo infection of human placental villi was performed to better understand interactions involving parasitic T. cruzi and human placental tissue. It was concluded that the strains of TcIa present parasitism in placental tissue, modulation of the innate immune system of the placenta, and cause intense detachment of the syncytiotrophoblast, a fact that may be more associated with abortion and premature birth events than the congenital transmission itself, justifying the low rate of this transmission mechanism by this genotype.
Non-crop plant diversity plays a fundamental role in the conservation of predatory mite (PM) and can be proposed as a banker plant system (BPS). BPSs provide plants that host natural enemies in greenhouses or field crops and may improve the efficiency of biological control. The aim of this study was to investigate if a diverse plant composition could be a suitable BPS for PMs in strawberry crops. A plant inventory characterized 22 species of non-crop plants harboring PMs. The most abundant PMs, in decreasing order, were Neoseiulus californicus, Neoseiulus anonymus, Euseius citrifolius, and Euseius concordis. PMs were randomly distributed among plants. We also found specific associations of Phytoseiidae species and phytophagous or generalist mites on plants. Due to this, four species were deemed suitable as banker plants: Capsicum sp., Leonurus sibiricus, Solanum americanum, and Urochloa mutica. Moreover, these plants combined a high PMs density and a low occurrence or absence of pest-mites. This study suggests shifting the traditional view that BPSs are composed of a limited number of species to use plant assemblages. This contributes to both conservation and augmentative biological control.
Herbicide-resistant weed management is one of the greatest agricultural challenges in crop production. Thus, the quick identification of herbicide-resistant weeds is extremely important for management. This study aimed to evaluate resistance to PSI-inhibiting herbicides (diquat) and physiological response to paraquat application in Sumatran fleabane [Conyza sumatrensis (Retz.) E. Walker; syn.: Erigeron sumatrensis Retz.]. The research was conducted with two C. sumatrensis biotypes, one susceptible and the other with multiple resistance to herbicides from five different modes of action (glyphosate, paraquat, diuron, saflufenacil, and 2,4-D). A dose–response assay was carried out to evaluate herbicide resistance to diquat in the paraquat-resistant C. sumatrensis biotype. The enzymatic activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX), hydrogen peroxide (H2O2) content, and chlorophyll a (Chl a) fluorescence were measured in both biotypes after paraquat (400 g ai ha−1) application. The dose–response assay confirmed resistance of C. sumatrensis to diquat with resistance factor levels of 26-fold and 6-fold for LD50 and GR50 values, respectively, compared with the susceptible biotype. Accumulation of H2O2 occurred more rapidly in the paraquat-susceptible biotype than in the resistant one. Paraquat treatment caused an increase in SOD and APX activity in the susceptible biotype, but antioxidant enzyme activities were unaffected by paraquat in the resistant one at 5 h after application (HAA). Chl a fluorescence increased across the first 4 HAA in both resistant and susceptible biotypes. However, at 24 HAA, the resistant biotype showed a decline in fluorescence close to untreated plants, while the susceptible biotype died, confirming resistance to diquat in the paraquat-resistant C. sumatrensis biotype. The paraquat-resistant biotype does not induce antioxidative enzymes, as a possible mechanism of resistance to paraquat, but shows rapid recovery of photosynthesis and continuous growth when subjected to paraquat, while the paraquat-susceptible biotype does not survive.
Drawing upon the thriving at work and agism literature, we added unexplored thriving antecedents (i.e., negative age-based metastereotypes and associated reactions) to the thriving nomological network. Additionally, we investigated the thriving-turnover intentions link throughout the lifespan. Parallel multiple mediator models were used to analyze the role played by threat and challenge in the relationship between negative age-based metastereotypes and overall thriving. Survey results (n = 326 employees) showed that threat and challenge mediated this relationship, yet differential relationships between antecedents and thriving appeared when analyzing thriving dimensions (i.e., learning and vitality) separately. Relatedly, turnover intentions were negatively predicted by overall thriving, but learning and vitality effects on turnover intentions were distinct across age groups. Findings recommend a clearer distinction between thriving dimensions role in the thriving experience throughout the lifespan. Overall, this study contends that the combination of thriving and agism literature contributes to further understand employee growth.
The present research aims to model, simulate and implement a new hybrid control approach based on a combination of proportional integral derivative (PID) Controller and Model Reference Adaptive Controller (MRAC), in which Lyapunov’s theory is used to ensure asymptotic stability to control a two degrees of freedom (DoF) manipulator driven by McKibben’s artificial pneumatic muscles. The MRAC controller works as a nonlinearity compensator and PID controller works during the transient period, as the MRAC performs poorly in this regime. This new approach is entitled Hybrid Model Reference Adaptive Controller (H-MRAC) and it has an unprecedented topological structure based on three terms. The feedforward term acts in disturbances rejection, the derivative term in oscillations damping and the feedback term acts in error convergence to zero. In this article, a control system dedicated to pneumatic manipulators was developed. As a result, proof of asymptotic convergence was performed for the proposed topological approach, which was validated on a two DoF manipulator. The proposed mechanism satisfactorily met the ISO/TS 15066 standard, and the position tracking obtained a global error of 37.69% and 51.01% smaller than found in the literature examples, entitled MRAC and A-PID, respectively, for simulations and 37.46% and 30.25% for experiments.
Antarctic lakes have generally simple periphyton communities when compared with those of lower latitudes. To date, assessment of microbial diversity in Antarctica has relied heavily on traditional direct observation and cultivation methods. In this study, sterilized cotton baits were left submerged for two years in two lakes on King George Island and Deception Island, South Shetland Islands (Maritime Antarctic), followed by assessment of diversity by metabarcoding using high-throughput sequencing. DNA sequences of 44 taxa belonging to four kingdoms and seven phyla were found. Thirty-six taxa were detected in Hennequin Lake on King George Island and 20 taxa were detected in Soto Lake on Deception Island. However, no significant difference in species composition was detected between the two assemblages (Shannon index). Our data suggest that metabarcoding provides a suitable method for the assessment of periphyton biodiversity in oligotrophic Antarctic lakes.
Reducing sedentary behaviour (SB) and increasing physical activity (PA) by sitting less and standing/walking more is advised to prevent chronic diseases. However, the mechanisms underlying this recommendation are not well established, especially in individuals with obesity living in low-income regions. The present study evaluated whether there are associations between PA indicators (PAI – standing time, walking time and the number of steps/d) and SB indicators (SBI – sitting/lying down time) with the hormonal profile and resting energy expenditure (REE) of adult women living in a low-income region. This is a cross-sectional study. We collected data on hormones (insulin resistance, leptin and thyroid axis), body composition (tetrapolar bioimpedance), REE (indirect calorimetry), and PAI and SBI (triaxial accelerometers, ActivPAL). Multivariable linear models adjusting for age and fat-free mass were performed. Fifty-eight women (mean age of 31 years and BMI of 33 kg/m2) were included. The mean sitting/lying down time and standing time were 16·08 and 5·52 h/d, respectively. Sitting/lying down time showed a direct association with free thyroxine (FT4) (β = 0·56 ng/dl; 95 % CI = −1·10, −0·02). Standing time showed a direct association with FT4 (β = 0·75 ng/dl; 95 % CI = 0·01; 1·48) and inverse association with free triiodothyronine (β = −2·83 pg/ml 95 % CI = −5·56, −0·10). There were no associations between PAI and SBI with the REE, insulin resistance, leptin and thyroid-stimulating hormone. Thus, decreased SB is associated with thyroid hormones levels but not with REE, insulin resistance or leptin in women with obesity living in low-income regions.
For an ascending HNN-extension
$G*_{\psi }$
of a finitely generated abelian group G, we study how a synchronization between the geometry of the group and weak periodicity of a configuration in
$\mathcal {A}^{G*_{\psi }}$
forces global constraints on it, as well as in subshifts containing it. A particular case are Baumslag–Solitar groups
$\mathrm {BS}(1,N)$
,
$N\ge 2$
, for which our results imply that a
$\mathrm {BS}(1,N)$
-subshift of finite type which contains a configuration with period
$a^{N^\ell }\!, \ell \ge 0$
, must contain a strongly periodic configuration with monochromatic
$\mathbb {Z}$
-sections. Then we study proper n-colorings,
$n\ge 3$
, of the (right) Cayley graph of
$\mathrm {BS}(1,N)$
, estimating the entropy of the associated subshift together with its mixing properties. We prove that
$\mathrm {BS}(1,N)$
admits a frozen n-coloring if and only if
$n=3$
. We finally suggest generalizations of the latter results to n-colorings of ascending HNN-extensions of finitely generated abelian groups.
The diagnosis of visceral leishmaniasis (VL) has improved with the search of novel antigens; however, their performance is limited when samples from VL/human immunodeficiency virus (HIV)-coinfected patients are tested. In this context, studies conducted to identify more suitable antigens to detect both VL and VL/HIC coinfection cases should be performed. In the current study, phage display was performed using serum samples from healthy subjects and VL, HIV-infected and VL/HIV-coinfected patients; aiming to identify novel phage-exposed epitopes to be evaluated with this diagnostic purpose. Nine non-repetitive and valid sequences were identified, synthetized and tested as peptides in enzyme-linked immunosorbent assay experiments. Results showed that three (Pep2, Pep3 and Pep4) peptides showed excellent performance to diagnose VL and VL/HIV coinfection, with 100% sensitivity and specificity values. The other peptides showed sensitivity varying from 50.9 to 80.0%, as well as specificity ranging from 60.0 to 95.6%. Pep2, Pep3 and Pep4 also showed a potential prognostic effect, since specific serological reactivity was significantly decreased after patient treatment. Bioinformatics assays indicated that Leishmania trypanothione reductase protein was predicted to contain these three conformational epitopes. In conclusion, data suggest that Pep2, Pep3 and Pep4 could be tested for the diagnosis of VL and VL/HIV coinfection.
Spatial disorientation is common in Alzheimer’s disease (AD), Mild Cognitive Impairment (MCI), and preclinical individuals with AD biomarkers. However, traditional neuropsychological tests lack ecological validity for the assessment of spatial orientation and to date, there is still no gold standard. The current study aimed to determine the validity and accuracy of two virtual reality tasks for the assessment of spatial orientation.
Methods:
We adapted two spatial orientation tasks to immersive virtual environments: a “survey to route” task in which participants had to transfer information from a map to their body position within a maze [Spatial Orientation in Immersive Virtual Environment Test (SOIVET) Maze], and an allocentric-type, route learning task, with well-established topographic landmarks (SOIVET Route). A total of 19 MCI patients and 29 cognitively healthy older adults aged 61–92 participated in this study. Regular neuropsychological assessments were used for correlation analysis and participant performances were compared between groups. Receiver Operating Characteristic (ROC) curve analysis was performed for accuracy.
Results:
The SOIVET Maze correlated with measures of visuoperception, mental rotation, and planning, and was not related to age, educational level, or technology use profile. The SOIVET Route immediate correlated with measures of mental rotation, memory, and visuoconstruction, and was influenced only by education. Both tasks significantly differentiated MCI and control groups, and demonstrated moderate accuracy for the MCI diagnosis.
Conclusion:
Traditional neuropsychological assessment presents limitations and immersive environments allow for the reproduction of complex cognitive processes. The two immersive virtual reality tasks are valid tools for the assessment of spatial orientation and should be considered for cognitive assessments of older adults.
The retention of human milk (HM) fat in nasogastric probes of infusion pumps can be observed during the feed of infants unable to suck at the mother’s breast. The lack of homogenisation of HM could contribute to the fat holding. Therefore, the present study evaluated (i) the influence of homogenisation on milk fat retaining in infant feeding probes and (ii) the in vivo effect of the homogenisation on lipid absorption by Wistar rats. The animals were fed with HM treated following two processing conditions, that is, pasteurised and homogenised–pasteurised. The animals were randomly subdivided into four experimental groups: water-fed (control), pasteurised milk, homogenised–pasteurised milk and pasteurised–skimmed milk. The results of food consumption, mass body gain, corporate metrics and plasma blood levels of total cholesterol did not show any difference (P < 0·05) among the three types of HM used in the experiments. The liver, intestine and intra-abdominal adipose tissue of the four groups of animals presented normal and healthy histology. The composition of fatty acids in the brain tissue of animals fed with homogenised HM increased when compared with the groups fed with non-homogenised HM. These values were 11·08 % higher for arachidonic acids, 6·59 % for DAH and 47·92 % for nervous acids. The ingestion of homogenised HM promoted higher absorption of milk nutrients. Therefore, the addition of the homogenisation stage in HM processing could be an alternative to reduce fat retention in probes and to improve the lipids’ absorption in the body.
Sex selection through sperm sorting offers advantages in regards selection pressure in high-producing livestock. However, the sex-sorting process results in sperm membrane and DNA damage that ultimately decrease fertility. We hypothesized that given the role of protamines in DNA packaging, protamine deficiency could account, at least partially, for the DNA damage observed following sperm sex sorting. To test this, we compared protamine status between unsexed and sexed spermatozoa from two bulls using the fluorochrome chromomycin A3 (CMA3) and flow cytometry. Then, we assessed embryo development following in vitro fertilization (IVF) using the same sperm treatments. Overall, sperm protamination was not different between sexed and unsexed semen. However, one of the two bulls displayed higher rates of protamine deficiency for both unsexed and sexed semen (P < 0.05). Moreover, unsexed semen from this bull yielded lower blastocyst (P < 0.05) and blastocyst hatching rates than unsexed sperm from the other bull. CMA3-positive staining was negatively correlated with cleavage (R2 85.1, P = 0.003) and blastocyst hatching (R2 87.6, P = 0.006) rates in unsexed semen. In conclusion, while the sex-sorting process had no effect on sperm protamine content, we observed a bull effect for sperm protamination, which correlated to embryo development rates following IVF.
Data on short-term peripheral intravenous catheter–related bloodstream infections per 1,000 peripheral venous catheter days (PIVCR BSIs per 1,000 PVC days) rates from Latin America are not available, so they have not been thoroughly studied.
Methods:
International Nosocomial Infection Control Consortium (INICC) members conducted a prospective, surveillance study on PIVCR BSIs from January 2010 to March 2018 in 100 intensive care units (ICUs) among 41 hospitals, in 26 cities of 9 countries in Latin America (Argentina, Brazil, Colombia, Costa Rica, Dominican-Republic, Ecuador, Mexico, Panama, and Venezuela). The Centers for Disease Control and Prevention (CDC) National Health Safety Network (NHSN) definitions were applied, and INICC methodology and INICC Surveillance Online System software were used.
Results:
In total, 10,120 ICU patients were followed for 40,078 bed days and 38,262 PVC days. In addition, 79 PIVCR BSIs were identified, with a rate of 2.06 per 1,000 PVC days (95% confidence interval [CI], 1.635–2.257). The average length of stay (ALOS) of patients without a PIVCR BSI was 3.95 days, and the ALOS was 5.29 days for patients with a PIVCR BSI. The crude extra ALOS was 1.34 days (RR, 1.33; 95% CI, 1.0975–1.6351; P = .040).
The mortality rate in patients without PIVCR BSI was 3.67%, and this rate was 6.33% in patients with a PIVCR BSI. The crude extra mortality was 1.70 times higher. The microorganism profile showed 48.5% gram-positive bacteria (coagulase-negative Staphylococci 25.7%) and 48.5% gram-negative bacteria: Acinetobacter spp, Escherichia coli, and Klebsiella spp (8.5% each one), Pseudomonas aeruginosa (5.7%), and Candida spp (2.8%). The resistances of Pseudomonas aeruginosa were 0% to amikacin and 50% to meropenem. The resistance of Acinetobacter baumanii to amikacin was 0%, and the resistance of coagulase-negative Staphylococcus to oxacillin was 75%.
Conclusions:
Our PIVCR BSI rates were higher than rates from more economically developed countries and were similar to those of countries with limited resources.