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Muscle and bone have been considered a functional unit that grows together early in life, deteriorates with aging, and can cause osteosarcopenia. Due to its importance in public health, detecting risk factors in early life is desirable. This study examined whether birth weight (BW) was associated with muscle–bone unit using dual energy X-ray absorptiometry (DXA) parameters in young women from the Nutritionists’ Health Study (NutriHS), a cohort study of undergraduates and Nutrition graduates. This cross-sectional analysis included 170 young healthy women who answered early life events-questionnaire, and had anthropometric, muscle tests and DXA-determined body composition and bone densitometry (iDXA-Lunar®). A blood sample was obtained for a subsample of 148 participants. Appendicular skeletal muscle mass index (ASMI) was calculated. BW was categorized in quartiles (BWq) and variables of interest compared by ANOVA. Associations of BWq with calf circumference (CC), handgrip, muscle performance tests, ASMI, bone mineral density and content (BMD and BMC), and plasma glucose, lipids, insulin, and 25-hydroxyvitamin D were performed using multiple linear regression and directed acyclic graph-recommended adjustments. Mean values of age, body mass index, and BW were 23.0 years (20.0–28.0), 22.9 ± 2.9 kg/m2, and 3199 ± 424 g, respectively. Comparing variables across BWq, significant differences in CC, handgrip, ASMI, and total body BMC were detected. Regression models adjusted for confounders showed associations of BWq with CC (β = 0.72, p = 0.005), handgrip (β = 1.53, p = 0.001), ASMI (β = 0.16, p = 0.022), total body BMC (β = 64.8, p = 0.005), total femur BMC (β = 0.70, p = 0.041), total body BMD (β = 0.02, p = 0.043), and lumbar spine BMD (β = 0.03, p = 0.028). We conclude that BW is associated with muscle–bone unit using DXA-parameters in Brazilian young healthy women from the NutriHS, suggesting a role for intrauterine environment for musculoskeletal health.
Low-income women are the group with the highest levels of obesity worldwide. In low-income settings, the use of predictive equations, which yield a measure of the individuals’ BMR, is a feasible approach to estimate the individuals’ total energy expenditure (TEE), using the factorial method (calculated-TEE = BMR × physical activity level), an important step of the obesity nutritional care. The present study aimed to identify the predictive equation that, in conjunction with metabolic equivalents of tasks (MET) data from accelerometers, yields the calculated-TEE with better agreement compared with the TEE measured by doubly labelled water (TEE-DLW). Forty-five women aged 19–45 years, with excess weight and mothers of undernourished children, were included. They received DLW to determine TEE (14 d); at the same time, they used triaxial accelerometers (7 d) to estimate their MET. The Bland–Altman method, paired-sample t tests, concordance correlation coefficient and root-mean-square error were used to assess the agreement. Maximum allowed differences were defined as 24 %, based on the within-variance coefficient of the energy intake of the sample. Eleven equations were studied. The calculated-TEE obtained by five equations showed non-significant bias: Dietary Reference Intake (Institute of Medicine (2005) Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids), FAO/WHO/UNU ((2001) Food and Nutrition Technical Report Series), Harris & Benedict ((1919) Proc Natl Acad Sci USA4, 370–373), Henry & Rees ((1991) Eur J Clin Nutr45, 177–185) and Schofield ((1985) Hum Nutr Clin Nutr39, 5–41). The mean percentage differences were –1·5, –0·8, 2·2, –2·2 and 2·0 %, respectively. Considering all parameters, FAO/WHO/UNU ((2001) Food and Nutrition Technical Report Series) equation performed slightly better than the others; nevertheless, no equation in conjunction with the estimated-MET showed a calculated-TEE with its CI for the Bland–Altman limits of agreement inside the pre-defined acceptable range.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Nearly all societies are bilingual (Appel & Muysken, 2006), a fact which places monolingualism in the minority. Multilingual individuals who live within the same national borders use the official language of the country in addition to their own to survive socially and economically. Globally, the position of English as a lingua franca has compelled people to learn it (Ur, 2010), which might suggest that in most cases, bilingualism is really understood as proficiency in English plus another language. In immigration contexts, families have to learn the dominant language—normally the most prestigious language—to be integrated to the new community, usually suppressing their minority language. According to Ferreira et al. (2016), the learners’ attitude towards the more prestigious linguistic group might have a positive impact on learning the new language, but maintaining the heritage language and culture seems to be an arduous task, even though the maintenance of heritage culture has benefits for first language (L1) literacy skills in addition to cognitive-linguistic variables, favouring a bi-dimensional model of acculturation (Berry, 1990).
Little is known about the long-term effect of breastfeeding on dietary habits. We examined the association between breastfeeding duration and adherence to current dietary patterns of young women. This was a cross-sectional analysis of 587 healthy women aged ≤45 years, undergraduates or nutrition graduates. Maternal characteristics and breastfeeding duration [<6; 6–<12; ≥12 months (reference)] were recalled. Diet was assessed using a food frequency questionnaire and patterns were identified using factor analysis by principal component. Adherence to patterns was categorized in tertiles; the first (T1 = reference) was compared to T2 + T3 (moderate-to-high adherence). Logistic regression was performed considering the minimal sufficient adjustment recommended by the directed acyclic graph. Median age was 22 (interquartile range (IQR) 20; 27) years and body mass index (BMI) 22.2 (IQR 20.4; 25.0) kg/m2. The four dietary patterns identified (Processed, Prudent, Brazilian and Lacto-vegetarian) explained 27% of diet variance. Women breastfed for <6 months showed lower chance of moderate-to-high adherence to the Prudent pattern (odds ratio (OR) = 0.53, p = 0.04). Breastfeeding was not associated with the other patterns. Maternal pre-pregnancy BMI was directly associated with moderate-to-high adherence to the Processed pattern (OR = 2.01, p = 0.03) and inversely to the Prudent pattern (OR = 0.52, p = 0.02). Higher adherence to the Brazilian pattern was associated with proxies of low socioeconomic status and the Lacto-vegetarian pattern with the opposite. Confirmation in prospective studies of the association found in this study between breastfeeding with the Prudent pattern in adult offspring could suggest that early feeding practices influence long-term dietary habits, which could then affect the risk of nutrition-related diseases.
The use of cactus cladodes in animal feed is well-established in semi-arid areas. The cactus Nopalea cochenillifera (L.) Salm-Dyck cladodes (Nopalea) have high acceptability amongst dairy cows and are resistant to carmine cochineal insects (Dactylopius opuntiae Cockerell), a problem in semi-arid regions, but in regions of prolonged drought, it has lower productivity compared with the cactus Opuntia stricta (Haw.) Haw cladodes (Opuntia), which is also resistant to the insect. The objective of the current study was to evaluate the intake and content of digestible material of dry matter (DM) and its components, feeding behaviour, microbial protein synthesis, nitrogen balance, blood parameters, performance and milk composition of Holstein cows fed a control diet, containing either Nopalea or Opuntia associated with different concentrate levels (225, 275, 325 and 375 g/kg). Ten cows with an initial average milk production of 20 ± 2.1 kg/day were distributed into a double 5 × 5 Latin square design. Diets containing 775 g roughage/kg and 225 g concentrate/kg promoted similar responses to the analysed variables regardless of the cactus cladode used, except for digestibility of neutral detergent fibre. Diets containing higher proportions of concentrate (325 and 375 g/kg) promoted greater DM intake and 3.5% fat-corrected milk yield. The diet containing Opuntia at 775:225 g/kg roughage:concentrate proportion is as effective as the control diet for Holstein cows producing 20 kg of milk/day. To promote greater milk production, higher proportions of concentrate should be added to diets using Opuntia.
Forage cactus is an important dry-season feed source for livestock in semi-arid regions, but in north-eastern Brazil, its contribution is limited by susceptibility to the carmine cochineal [Dactylopius opuntiae (Cockerell)] insect. New cactus germplasm shows superior agronomic performance, but the nutritive value of this material has not been adequately described. The objective of the current study was to assess the divergence in chemical composition and rate and extent of in vitro degradation of these genotypes. The treatments were 13 spineless cactus genotypes, eight of which were insect resistant types, two semi-resistant and three susceptible to the carmine cochineal. Treatments were arranged in a randomized complete block design and were replicated three times. Nutritional divergence was assessed using canonical variate analysis and hierarchical agglomerative clustering, using the variables: crude protein, total and non-fibrous carbohydrates, degradation rate and potential dry matter degradation. Five distinct nutritional groups were identified: Group I (OO), Group II (F-13 and F-15), Group III (OEA, OEM, COP, IPA 20 and GG), Group IV (V-16 and F-08) and Group V (Miuda, IS and F-21). Group II (F-13 and F-15; resistant genotypes) showed a chemical composition degradability in vitro suggesting it may have the greatest nutritive value as ruminant feed, while Group I had the least. Spineless cactus genotypes resistant to the carmine cochineal showed nutritional characteristics similar to or better than traditionally used cactus genotypes, such as Gigante and IPA 20, which can expand the range of options for using this forage.
The aim of this review is to compare the performance of different reproductive programs using natural service, estrus synchronization treatment before natural service (timed natural breeding (TNB)), artificial insemination (AI) following estrus detection and timed artificial insemination (TAI) in beef herds. It is well known that after parturition the beef cow undergoes a period of anestrous, when they do not exhibit estrus, eliminating the opportunity to become pregnant in the early postpartum by natural mating or by AI after detection of estrus. Hormonal stimulation is already a consistent and well-proven strategy used to overcome postpartum anestrus in beef herds. Basically, hormones that normally are produced during the estrous cycle of the cow can be administered in physiological doses to induce cyclicity and to precisely synchronize follicular growth, estrus and ovulation. Furthermore, two options of mating may be used after hormonal stimulation: natural service (i.e. utilization of bull service after synchronization, referred to as TNB) and TAI. These strategies improve the reproductive efficiency of the herds compared with natural service without estrus induction or synchronization. After the first synchronized service, the most common strategy adopted to get non-pregnant cows pregnant soon is the introduction of clean-up bulls until the end of the breeding season. However, methods to resynchronize non-pregnant cows after the first service are already well established and offer a potential tool to reduce the time for subsequent inseminations. Thus, the use of these technologies enable to eliminate the use of bulls by using resynchronization programs (i.e. two, three or four sequential TAI procedures). The dissemination of efficient reproductive procedures, such as TNB, TAI and Resynch programs, either isolated or in combination, enables the production of a greater quantity (obtaining increased pregnancy rates early in the breeding season) and quality (maximization of the use of AI with superior genetic sires) of beef calves. These technologies can contribute to improve the production efficiency, and consequently, improve livestock profitability.
Although a national programme for control of visceral leishmaniosis (VL) is being run in Brazil, the disease continues to spread. This programme is essentially based on culling infected dogs from endemic regions. Thus, there is an urgent need to develop other control measures against VL to deter its advance. Here, a subunit vaccine, a recombinant vaccine, an insecticide-impregnated collar and the associations between these measures were evaluated for reducing the incidence of Leishmania infection in dogs. This was through a cohort study conducted in an endemic region of Brazil, considering the incidence and time of total exposure over a period of 1 year. The incidence of VL was estimated by means of serological and molecular diagnostic tests, 180 and 360 days after the application of the control measures. The estimates of the effectiveness (EF) were not significant in any cohort. The EF of the subunit vaccine, the recombinant vaccine and the collar were 26.4%, 32.8% and 57.7% and the upper limit of the 95% confidence interval for EF were 63.7%, 67.9% and 82.5%, respectively. In conclusion, under the conditions of this study, none of the immunogens for VL control was sufficiently effective to protect dogs against infection. On the other hand, use of collars impregnated with insecticide seems to constitute a method with better prognosis, corroborating other studies in this field.
The aim of this study was to determine the prevalence and risk factors for human papillomavirus (HPV) infection in the Southern region of the State of Bahia, evaluating the performance of alternative complementary methods for cervical lesion detection. Cervical samples from women who attended healthcare units were collected and diagnosed by visual inspection, cervical cytology and nested polymerase chain reaction (PCR). Moreover, hemi-nested PCR was performed to detect different HPV genotypes. The prevalence of HPV infection was 47·7%, with genotype 16 detected in most cases. Infection was associated with dyspareunia and bleeding (P < 0·001, odds ratio (OR) 5·6, 95% confidence interval (CI) 2·815–11·14) and hormonal contraceptive use (P = 0·007, OR 2·33, 95% CI 1·25–4·34). There was a positive correlation between positive PCR and positive visual inspection, cervical cytology and symptoms reported. Furthermore, visual inspection was twice as specific, and had a greater positive predictive value than cytology. We showed a high prevalence of HPV infection in Southern Bahia, with HPV 16 being the most common type, and visual inspection being most effective at detecting HPV lesions, corroborating the suggestion that it can be applied in routine gynecologic examinations for low-income populations.
The visceralizing potential of apparently dermotropic Leishmania donovani in Sri Lanka (L. donovani-SL) was investigated through long-term follow-up of cutaneous leishmaniasis (CL) patients and in vivo and in vitro experimental infection models. CL patients (n = 250) treated effectively with intra-lesional antimony therapy were followed-up six monthly for 4 years. There was no clinical evidence of visceralization of infection (VL) during this period. Infection of BALB/c mice with L. donovani-SL (test) through intra-dermal route led to the development of cutaneous lesions at the site of inoculation with no signs of systemic dissemination, in contrast to the observations made in animals similarly infected with a visceralizing strain of L. donovani-1S (control). Cytokine (IL-10, IFN-γ) release patterns of splenocytes and lymph node cell cultures derived from mice primed with experimental infections (with either test or control parasites) revealed significantly high IFN-γ response associated with test mice with CL, while prominent IL-10 levels were observed in association with control mice with VL. Furthermore, diminished infection efficiency, intracellular growth and survival of L. donovani-SL parasites compared with L. donovani-1S were evident through in vitro macrophage infection experiments. These studies confirm, for the first time, the essential dermotropic nature of L. donovani-SL suggesting natural attenuation of virulence of local parasite strains.
The objective of this study was to evaluate the effects of the energy restriction of gestation of adult ewes from day 45 to day 115 on lamb live performance parameters, carcass and meat traits. In experiment I, dietary energy was restricted at 70% of the metabolizable energy (ME) requirements, after which ewes were re-fed ad libitum until lambing. In experiment II, dietary energy was restricted at 60% of the ME requirements, and ewes were re-fed to ME requirements until lambing. All ewes grazed together from the end of the restriction periods to weaning. Lambs were weaned and lot fed until slaughter. Feed intake, weight gain and feed efficiency were recorded, and body fat thickness and ribeye area (REA) were measured in the longissimus thoracis muscle. After slaughter, carcass weight and yield, fat depth, carcass and leg length, and frenched rack and leg weights and yields were determined. Muscle fiber type composition, Warner-Bratzler shear force, pH and color were determined in the longissimus lumborum muscle. In experiment I, energy restriction followed by ad libitum feeding affected lamb birth weight (P<0.05); however, no effects (P>0.05) were observed on later BW, REA, BF or carcass traits. Lambs born to non-restricted-fed ewes had higher (P<0.05) weight and yield of the frenched rack cut and their meat tended (P=0.11) to be tender compared with that of lambs from restricted ewes. The percentage of oxidative muscle fibers was lower for lambs born to non-restricted ewes (P<0.05); however, no effects of ewe treatment were observed on other muscle fiber types. For experiment II, energy restriction followed by ME requirements feeding, affected (P<0.01) pre-weaning live weight gain, weaning and final weights. Lambs from restricted ewes had higher (P<0.05) feed intake as % of leg weight and a trend to be less efficient (P=0.16) than lambs from unrestricted dams. Ribeye area and BF were not influenced by treatment. Treatment significantly affected slaughter weight, but had no effects on carcass yield and traits or on meat traits. The results obtained in both experiments indicate submitting ewes to energy restriction during gestation affects the performance of their progeny but the final outcome would depend on the ewe’s re-feeding level during late gestation and the capacity of the offspring to compensate the in utero restriction after birth.
Euthanasia of infected dogs is one of the measures adopted in Brazil to control visceral leishmaniasis (VL) in endemic areas. To detect infected dogs, animals are screened with the rapid test DPP® Visceral Canine Leishmaniasis for detection of antibodies against K26/K39 fusion antigens of amastigotes (DPP). DPP-positives are confirmed with an immunoenzymatic assay probing soluble antigens of promastigotes (ELISA), while DPP-negatives are considered free of infection. Here, 975 dogs from an endemic region were surveyed by using DPP, ELISA and real-time PCR (qPCR) for the diagnosis of VL. When DPP-negative dogs were tested by qPCR applied in blood and lymph node aspirates, 174/887 (19·6%) were positive in at least one sample. In a second sampling using 115 cases, the DPP-negative dogs were tested by qPCR in blood, lymph node and conjunctival swab samples, and 36/79 (45·6%) were positive in at least one sample. Low-to-moderate pairwise agreement was observed between all possible pair of tests. In conclusion, the official diagnosis of VL in dogs in Brazilian endemic areas failed to accuse an expressive number of infected animals and the impact of the low accuracy of serological tests in the success of euthanasia-based measure for VL control need to be assessed.
Zoonotic diseases are a significant health threat for humans and animals. To better understand the epidemiology, etiology, and pathology of infectious agents affecting humans and animals combined approaches are needed. Here we describe an epidemiological investigation conducted by physicians and veterinarians after a reported case of psittacosis. Upon admission suffering from respiratory distress syndrome in a hospital and with a history of bird contact, a female patient was serologically diagnosed with psittacosis. After the case notification, veterinarians were able to investigate the source of infection by detecting Chlamydia psittaci in her pet cockatiel. The bird was hospitalized and successfully treated. In addition, the establishment where the pet bird was purchased was traced and through molecular techniques other birds intended to be sold as pets tested positive for C. psittaci. As a result, sanitary measures were applied and the establishment then was closed down. The birds intended for the pet commerce were treated and retested with negative molecular results for C. psittaci, thus avoiding disease propagation. Reliable data about zoonotic diseases can only be generated through the application of multidisciplinary approaches which take into account the epidemiological factors and interactions of humans, animals and their environments as an integrated system.
Licuri (Syagrus coronate) cake is a biodiesel by-product used in ruminant feed as a beneficial energy source for supplementation in managed pastures. The objective was to evaluate the performance, digestibility, nitrogen balance, blood metabolites, ingestive behavior and diet profitability of eight crossbred Holstein (3/4)×Gyr (5/8) multiparous cows (480±25 kg BW and 100 days milking) grazing and supplemented with licuri cake partially replacing ground corn and soybean meal in concentrate (0, 200, 400 and 600 g/kg in dry matter (DM)), distributed in an experimental duplicated 4×4 Latin square design. Licuri cake partially replacing ground corn and soybean meal increased (P<0.01) the intake and digestibility of ether extract and decreased the non-fiber carbohydrates; however, there were no influences on the intakes of DM, CP, NDF and total digestible nutrients (TDN). The digestibilities of DM, CP and NDF were not influenced by licuri cake addition. There was a decrease trend on TDN digestibility (P=0.08). Licuri cake replacing ground corn and soybean meal in concentrate did not affect the intake; fecal, urinary and mammary excretions; N balance; and triglycerides concentrations. However, the blood urea nitrogen (P=0.04) concentration decreased with the licuri cakes inclusion in cow supplementation. There was an increasing trend for serum creatinine (P=0.07). Licuri cake inclusion did not affect body condition score, production, yield, protein, lactose, total solids and solid non-fat contents of milk and Minas frescal cheese. There was a linear decrease in average daily weight gain (g/day). The milk fat concentration and cheese fat production (P<0.1) presented a linear increase with partial replacement of ground corn and soybean meal with licuri cakes. The addition of licuri cake did not alter the time spent feeding, ruminating or idling. There was an increasing trend in NDF feeding efficiency (P=0.09). The replacing of ground corn and soybean meal with licuri cake up to 600 g/kg decreased the concentrate cost by US$0.45/cow per day. Licuri cake replacing corn and soybeans (400 g/kg) in concentrate promoted a profit of US$0.07/animal per day. Licuri cake is indicated to concentrate the supplementation of dairy cows with average productions of 10 kg/day at levels up to 400 g/kg in the concentrate supplement because it provides an additional profit of US$0.07/animal per day and increased milk and Minas frescal cheese fat without negative effects on productive parameters.
Thorough studies on whether point prevalence surveys of healthcare-associated infections (HAIs) can be used to reliably estimate incidence of surgical site infections (SSIs) are scarce. We examined this topic using surveillance data of 58 hospitals that participated in two Dutch national surveillances; HAI prevalence and SSI incidence surveillance, respectively. First, we simulated daily prevalences of SSIs from incidence data. Subsequently, Rhame & Sudderth's formula was used to estimate SSI incidence from prevalence. Finally, we developed random-effects models to predict SSI incidence from prevalence and other relevant variables. The prevalences simulated from incidence data indicated that daily prevalence varied greatly. Incidences calculated with Rhame & Sudderth's formula often had values below zero, due to the large number of SSIs occurring post-discharge. Excluding these SSIs, still resulted in poor correlation between calculated and observed incidence. The two models best predicting total incidence and incidence during initial hospital stay both performed poorly (proportion of explained variance of 0·25 and 0·10, respectively). In conclusion, incidence of SSIs cannot be reliably estimated from point prevalence data in Dutch hospitals by any of the applied methods. We therefore conclude that prevalence surveys are not a useful measure to give reliable insight into incidence of SSIs.
A systematic study was performed concerning the production, characterization, and application of BDD and BDND films grown on Ti substrate to degrade brilliant green dye using an electrochemical flow reactor. Films were grown in a hot filament chemical vapour deposition (HFCVD) reactor using H2/CH4 (BDD) and H2/CH4/Ar (BDND) gas mixtures. Boron doping was performed by dissolution of B2O3 in methanol in the appropriate B/C ratio to obtain good conductive electrodes. The electrolysis was carried out using BDD/Ti and BDND/Ti as anode material analyzing the influence of different current densities and flow rates. During the electrolysis, aliquots of the treated solution were analyzed by UV-Vis and Total Organic Carbon (TOC) measurements. The electrode efficiencies were compared considering the color removal as well as the TOC mineralization in the end of each electrolysis. The absorption bands intensity from UV/Vis spectra clearly decreased up to their completely vanishing at current density of 100 mA/cm2 for both electrodes. These results were corroborated by TOC measurements where 50% of the organic material was removed.
The parameter optimizations of square-wave anodic stripping voltammetry using boron doped diamond (BDD) electrodes with different doping levels for cadmium detection were studied. The optimized relation among the peak current with the pulse frequency, the amplitude, and the potential increment for highly (1019 cm-3) and heavily BDD (1021 cm-3) electrodes was considered. The peak currents were measured around -0.75 V vs. Ag/AgCl for Cd2+ concentration ranged from 1 to 20 ppb. Both BDD films provided detection limits lower than 5 ppb showing that these electrodes are suitable to use in a mercury-free method to determine cadmium trace levels in water.
Polyaniline (PAni)/B-doped diamond/carbon fiber (CF) ternary composites were produced and characterized, aiming their application as electrodes for supercapacitor device. In order to optimize the composite properties, structurally different CF substrates, heat treated at 1000 and 2000°C, were used to grown diamond films. Moreover, the diamond films were grown on CF in two different morphologies, boron doped micro and nanocrystalline diamond (BDD/BDND), by Hot Filament Chemical Vapor Deposition (HFCVD) technique. FEG-SEM images showed that PAni covered and enwrapped the diamond/CF surfaces, producing tridimensional electrodes. Raman spectra confirmed the PAni formation for all composites. Electrochemical characterizations indicated that the PAni/BDD/CF2000 composite has the highest current density and capacitance response among the studied composites combinations. In addition, it showed the most reversible oxidation and reduction processes, the greatest charge storage capacity as well as the lowest charge transfer resistance.