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In this work, we have theoretically investigated a model for the poly(2-methoxy-5(2'- ethylhexyloxy)-p-phenylenevinylene) (MEH-PPV) photodegradation based on structural models for MEH-PPV oligomers in vacuum and in solvent (chloroform). We investigated how the incorporation of oxygen and breaking of vinyl double bonds affect the absorption spectra. The theoretical results are in excellent agreement with the experimental data if we assume that the incorporation of carbonyl group is the main mechanism associated with the photodegradation processes.
Gazetting and maintaining protected areas (PAs) are political processes and, as such, depend on wider society’s support in order to achieve their aims. In this paper, we evaluated the influence of gender, education, age, income, place of origin and place of residence on public support for PAs in the Brazilian state of Amapá, a new tropical forest frontier. We gathered 615 complete interviews with adults living in both rural and urban settings. We found that most (90.5%) of the participants support PAs and that this attitude is more likely to exist among urban than rural participants. We found that gender, education, age, income and place of origin did not influence support for PAs. Biodiversity conservation is the most common reason why PAs receive public support. In contrast, participants who do not favour PAs see them as providing no benefit to people. We suggest that support by local political leaders from dominant and rival political parties for conservation helps to promote acceptance of PAs by stakeholders. However, relatively low support for PAs among rural participants could indicate that the expectations of these populations regarding the social benefits associated with this conservation policy have yet to be fulfilled.
Invasive winter annual grass infestations on rangeland accumulate large quantities of litter on the soil surface, as plants senesce yearly and decompose slowly. It has been speculated that winter annual grass litter can adsorb soil-active herbicides and reduce overall performance. Three experiments were conducted from 2017 to 2018 at the Colorado State University Weed Research Laboratory to evaluate interception and subsequent desorption of herbicides applied to litter from three invasive winter annual grass species with simulated rainfall. Imazapic, rimsulfuron, and indaziflam were applied to medusahead [Taeniatherum caput-medusae (L.) Nevski], ventenata [Ventenata dubia (Leers) Coss.], and downy brome (Bromus tectorum L.) litter at two amounts (equivalent to 1,300 and 2,600 kg ha−1). Rainfall was simulated at 3, 6, 12, and 24 mm at 0, 1, and 7 d after herbicide application. Herbicide concentration from the collected rainfall was measured using liquid chromatography–tandem mass spectrometry. At 2,600 kg ha−1, B. tectorum herbicide interception was 84.3%, while V. dubia and T. caput-medusae averaged 76% herbicide interception. There were no differences in desorption among the three litter types. Simulated rainfall at 0 d after application recovered 100% of the intercepted rimsulfuron and imazapic from B. tectorum litter, while recovery decreased to 65% with rainfall at 1 or 7 d after application. Only 54% of indaziflam could be recovered at 0 d, and recovery decreased to 33% when rainfall was applied at 1 or 7 d after application. Applying soil-active herbicides before forecasted rain or tank mixing with a POST herbicide to provide initial control could potentially increase the amount of herbicide reaching the soil and provide more consistent invasive winter annual grass control.
We compare the efficiency of mechanical or enzymatic methods, and their combination, for the isolation of ovarian preantral follicles (PFs) from collared peccaries. The ovaries from six females were subjected to the different methods investigated here. For the enzymatic method, ovary fragments were exposed to collagenase type IV in TCM-HEPES medium; the mechanical procedure was based on ovarian cortex dissociation by using a scalpel blade. The residual solution obtained after the mechanical isolation was subjected to the enzymatic procedure. The number of isolated PFs was quantified and classified as primordial, primary, or secondary; their viability was assessed using trypan blue dye assay. To confirm the results, PFs derived from the most efficient method were evaluated for integrity using scanning electron microscopy (SEM) and subjected to a 24 h in vitro culture for subsequent evaluation of viability by using fluorescent probes. A higher number of PFs (P < 0.05) was obtained from the enzymatic method (961.7 ± 132.9) in comparison with the mechanical method (434.3 ± 88.9), but no difference was observed between the two methods and their combination (743.2 ± 92.8). The trypan blue assay showed that the enzymatic method (98.7 ± 0.6%) provided the highest percentage of viable follicles (P < 0.05). Furthermore, SEM confirmed the ultrastructural integrity of the surface architecture of peccary PFs isolated by the enzymatic procedure; epifluorescence microscopy was used to confirm their viability (86.0%). In conclusion, we suggest that the enzymatic method investigated here is useful for the isolation of viable ovarian PFs from collared peccaries.
Many school-based interventions for obesity prevention have been proposed with positive changes in behavior, but unsatisfactory results on weight change. The objective was to verify the effectiveness of a combined school and home-based obesity prevention program on excessive weight gain in adolescents. Teachers delivered the school-based primary prevention program to fifth and sixth graders (9 schools, 48 control classes, 49 intervention classes), which included encouraging healthy eating habits and physical activity. A subgroup of overweight or obese adolescents also received a home-based secondary prevention program delivered by community health professionals. Schools were randomized to intervention or control group. Intent-to-treat analysis used mixed models for repeated continuous measures and considered the cluster effect. The main outcomes were changes in body mass index (BMI) and percent body fat (%body fat) after one school-year of intervention and follow-up. Against our hypothesis, BMI increased more in the intervention group than in the control group (Δ=0.3kg/m2; p=0.05) with a greater decrease in %body fat among boys (Δ=-0.6%; p=0.03) in the control group. The intervention group increased physical activity by 12.5 minutes per week compared with the control group. Female adolescents in the intervention group ate healthier items more frequently than in the control group. The subgroup who received both the school and home interventions had an increase in %body fat than in the control group (Δ=0.89%; p=0.01). In this study, a behavioral change led to a small increased in physical activity and healthy eating habits but also to an overall increase in food intake.
Asthma-obesity is a multifactorial disease, with specific asthma phenotypes which aggravate due to overweight and an unbalanced diet. Futhermore, asthmatic obese are corticotherapy-resistant. This study was to evaluate the effects of an interdisciplinary intervention on food consumption, body composition, lung function and adipokines in obese asthmatic and non-asthmatic adolescents and to investigate the influence of nutrients on lung function. Obese non-asthmatic (n=42) and obese asthmatic (n=21) adolescents of both sexes participated this study. Was evaluated food intake, adiponectin, leptin and C-reactive protein, body composition, asthma symptoms and lung function. The interdisciplinary intervention had the duration of one year and the team consisted of nutritionists, psychologists, physiotherapists, physicians and physical education professionals. After intervention there was a reduction (p≤0.01) in body mass index, body fat percentage, visceral and subcutaneous fat, an increase (p≤0.01) in lean mass and lung function variables in both groups, except the relation between forced expiratory volume in the first second and forced vital capacity (FEV1/FVC) in non-asthmatic. Also, there was lower (p≤0.01) lipid consumption and cholesterol in both groups. The highest energy consumption (β= -0.02) was associated to lower values of forced vital capacity (FVC). Carbohydrate consumption (β= -0.06) and cholesterol were negative predictors (β= -0.05) in FEV1/FVC. The consumption of calcium (β= 0.01), fibers (β= 1.34) and vitamin A (β= 0.01) were positive predictors of FEV1/FVC. Asthma-obesity interdisciplinary treatment promoted improved food consumption and lung function in adolescents and demonstrated that the consumption of nutrients influenced the increase in lung function.
The non-dimensional dissipation rate
are the viscous energy dissipation rate, integral length scale of turbulence and root-mean-square of the velocity fluctuations, respectively, is computed and analysed within the turbulent/non-turbulent interfacial (TNTI) layer using direct numerical simulations of a planar jet, mixing layer and shear free turbulence. The TNTI layer that separates the turbulent and non-turbulent regions exists at the edge of free shear turbulent flows and turbulent boundary layers, and comprises both the viscous superlayer and turbulent sublayer regions. The computation of
is made possible by the introduction of an original procedure, based on local volume averages within spheres of radius
, combined with conditional sampling as a function of the location with respect to the TNTI layer. The new procedure allows for a detailed investigation of the scale dependence of several turbulent quantities near the TNTI layer. An important achievement of this procedure consists in permitting the computation of the turbulent integral scale within the TNTI layer, which is shown to be approximately constant. Both the non-dimensional dissipation rate and turbulent Reynolds number
vary in space within the TNTI layer, where two relations are observed:
. Specifically, whereas the viscous superlayer and part of the turbulent sublayer display
, the remaining of the turbulent sublayer exhibits
, which is consistent with non-equilibrium turbulence (Vassilicos, Annu. Rev. Fluid Mech. vol. 47, 2015, pp. 95–114).
New tools from neuroscience allow design researchers to explore design neurocognition. By taking the advantage of EEG's temporal resolution we give up spatial resolution to focus on the performance of time-related design tasks. This paper presents results from an experiment using EEG to measure brain activation to study mechanical engineers and architects to compare their design neurocognition. In this study, we adopted and extended the tasks described in a previous fMRI study of design neurocognition reported in the literature. The block experiment consists of a sequence of 3 tasks: problem solving, basic design and open design using a physical interface. The block is preceded by a familiarizing pre-task using the physical interface and then extended to a fourth task using free-hand sketching. Brainwaves were collected from both mechanical engineers and architects. Results comparing 36 mechanical engineers and architects while designing were produced. These results indicate design cognition differences between the two domains in task-related power between the problem-solving task and the design tasks, in temporal resolution and transformed power.
Semen analysis is a fundamental part of male fertility investigation. Samples are produced by masturbation, ideally in a private room nearby to the andrology laboratory or submitted within one hour if produced off-site. The ejaculate should be collected in a wide-mouthed, clean, glass or plastic container, from a batch confirmed to be non-toxic to spermatozoa. Patients should be given clear instructions about collection of their sample. To ensure consistency and reliable interpretation of results, there should be a minimum of two days and maximum of seven days abstinence (1), and the complete sample should be collected. Loss of the first portion of the ejaculate, which mainly comprises sperm-rich prostatic fluid, may significantly affect sperm count and concentration.
The aim of the present study was to evaluate the prevalence of vitamin B12 (B12) deficiency in kidney transplant recipients (KTR) and its possible association with B12 dietary intake, body adiposity and immunosuppressive drugs. In this cross-sectional study, we included 225 KTR, aged 47·50 (sd 12·11) years, and 125 (56 %) were men. Serum levels of B12 were determined by chemiluminescent microparticle intrinsic factor assay and the cut-off of 200 pg/ml was used to stratify KTR into B12-sufficient or B12-deficient group. B12 dietary intake was evaluated by three 24 h dietary recalls and was considered adequate when ≥2·4 μg/d. Body adiposity was estimated after taking anthropometric measures and using the dual-energy X-ray absorptiometry (DXA) method. B12 deficiency was seen in 14 % of the individuals. B12-deficient group, compared with the B12-sufficient group, exhibited lower intake of B12 (median 2·42 (interquartile range (IQR) 1·41–3·23) v. 3·16 (IQR 1·94–4·55) μg/d, P = 0·04) and higher values of waist circumference (median 96·0 (IQR 88·0–102·5) v. 90·0 (IQR 82·0–100·0) cm, P = 0·04). When the analysis included only women, B12 deficiency was associated with higher total and central body adiposity measurements obtained with anthropometry (BMI, body adiposity index, waist and neck circumferences) and DXA (total and trunk body fat). Among individuals with adequate intake of B12, the deficiency of this vitamin was more frequently seen in those using mycophenolate mofetil (MMF) (17 %) v. azathioprine (2 %), P = 0·01. In conclusion, the prevalence of B12 deficiency in KTR was estimated as 14 % and was associated with reduced intake of B12 as well as higher adiposity, especially in women, and with the use of MMF.
Maternal physical activity induces brain functional changes and neuroplasticity, leading to an improvement of cognitive functions, such as learning and memory in the offspring. This study investigated the effects of voluntary maternal physical activity on the gene expression of the neurotrophic factors (NTFs): BDNF, NTF4, NTRK2, IGF-1 and IGF-1r in the different areas of mother’s brain, placenta and foetus brain of rats. Female Wistar rats (n = 15) were individually housed in voluntary physical activity cages, containing a running wheel, for 4 weeks (period of adaptation) before gestation. Rats were classified as inactive (I, n = 6); active (A, n = 4) and very active (VA, n = 5) according to daily distance spontaneously travelled. During gestation, the dams continued to have access to the running wheel. At the 20th day of gestation, gene expression of NTFs was analysed in different areas of mother’s brain (cerebellum, hypothalamus, hippocampus and cortex), placenta and the offspring’s brain. NTFs gene expression was evaluated using quantitative PCR. Very active mothers showed upregulation of IGF-1 mRNA in the cerebellum (36.8%) and NTF4 mRNA expression in the placenta (24.3%). In the cortex, there was a tendency of up-regulation of NTRK2 mRNA (p = 0.06) in the A and VA groups when compared to I group. There were no noticeable changes in the gene expression of NTFs in the offspring’s brain. Our findings suggest the existence of a developmental plasticity induced by maternal physical activity in specific areas of the brain and placenta representing the first investment for offspring during development.
Regeneration from seed affects species assembly in plant communities, and temperature is the most important environmental factor controlling the germination process. Thermal dependence of seed germination is thus associated with species occurrence in an ecosystem. Hence, we aimed to investigate the role of temperature on seed germination of ten tree species from the western Brazilian Amazon. Seeds were collected in the state of Rondônia, Brazil, and set to germinate under constant temperatures ranging from 10 to 40°C in germination chambers. We calculated germination capacity (G%), germination rate (GR50, reciprocal of germination time), and thermal parameters, such as cardinal temperatures and thermal time requirements. Most species had a large range of temperatures showing G% ≥80%, with optimal temperature varying from 20 to 40°C. Base temperature ranged from 6 to 12°C and ceiling temperatures were mainly >40°C. Astronium lecointei and Parkia nitida showed high germination capacity under temperatures of 35–40°C, while germination of Theobroma cacao dropped from 100% to zero under temperatures between 37 and 40°C. The climax species Cedrela fissilis had the slowest germination time (10 days) and highest thermal time requirement, while seeds of Enterolobium schomburgkii (a late-successional species) germinated within the first day of the experiment. Rapid recruitment of Amazon species could be favoured with treefall disturbance, which increases temperatures in the understory, but sharp limits might be found in the supra-optimal range of temperatures. Such patterns might indicate different regeneration strategies in the tropical rainforest, providing important information regarding seed germination among Amazon species.
Levamisole (Lms) is an anthelminthic drug with immunomodulatory activity. Chagas disease (CD) is caused by Trypanosoma cruzi and there is very low access to the drugs available, benznidazole (Bz) and nifurtimox, both far from ideal. In a drug-repurposing strategy to test potential activity as antiparasitic and immunomodulatory agent for CD, Lms was assayed on acute T. cruzi murine infection, alone and in co-administration with Bz. During protocol standardization, 100 and 10 mpk of Bz given for five consecutive days resulted in parasitaemia suppression and 100% animal survival only with the highest dose. Flow cytometry showed that both optimal (100 mpk) and suboptimal (10 mpk) doses of Bz equally decreased the plasma levels of cytokines commonly elevated in this acute infection model. Lms alone (10–0.5 mpk) did not decrease parasitaemia nor mortality rates. Co-administration was investigated using the suboptimal dose of Bz and different doses of Lms. While Bz 10 mpk did not alter parasitaemia, the combo partially reduced it but only slightly promoted animal survival. This effect could be related to Th1-response modulation since interleukin-6 and interferon-γ were higher after treatment with the combo.
With the increase in the number and intensity of disasters, integrated risk management has been a subject of discussion in Brazilian health system, in which the local level plays an important role. Competency Mapping of Managers working at a Municipal Health Office from a Metropolitan Area of Curitiba, Southern Brazil was developed.
To describe gaps in core competencies identified for Surveillance and Control of Risks and Threats.
The Public Health Core Competencies contained in the booklet: A Regional Framework for the Americas, of the Pan American Health Organization, originated a semi-structured self-assessment questionnaire. A Likert scale with levels of proficiency (from one to five) was aggregated to the 56 specific core competencies. It was applied to a sample of 78 managers between the months of October 2017 and January 2018. The data obtained were submitted to quantitative analysis. Gaps (Training Priority Degree) were defined according to the grade of importance and expression by means of a arithmetic mean and standard deviation.
Gaps were identified for the competencies: Design disaster risk management plans for natural, technological and biological threats so as to mitigate their impact on health (2.82 ± 1.16); Design investment projects for reducing the health risks of disasters (2.8 ±1.07); Provide an immediate response to threats, risks and damage from disasters based on the risk assessment, in order to protect health (2.89 ± 1.13); Plan and execute post-disaster reconstruction, based on the damage identified for the immediate restoration and protection of the population’s health (2.81 ± 1.11).
The degree of expression for these competencies indicate the need of preparing public health managers for surveillance, by monitoring the exposure of people or population groups to environmental agents, or their effects with an integrated approach to injuries and the etiology of emergencies and disasters.