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Atrazine is a synthetic herbicide applied to control broadleaf weeds in different crops. In many parts of the world, atrazine is mainly applied for controlling weeds in maize fields. However, studies on the possible adverse effects of atrazine on maize crop can hardly be found in literature. The present study was therefore conducted to evaluate the effect of atrazine on different characteristics of maize seedlings including germination, growth, chlorophyll contents, soluble sugars, proteins and proline levels, ions accumulation, cell viability, and cell injury. In addition, the effects of atrazine on reactive oxygen species (ROS) accumulation and antioxidant enzymes activities in maize seedlings were estimated. It was found that at high concentration, atrazine slightly but significantly inhibited seed germination and growth of maize seedlings. Light-harvesting pigments (chlorophylls a and b, and total carotenoids) exhibited a higher sensitivity to atrazine and were negatively impacted by atrazine at doses above 50 ppm. Atrazine caused an increase in soluble sugars at all tested doses and decrease in soluble proteins at the highest tested dose. Exposure of maize seedlings to atrazine resulted in an increased cell injury and decreased cell viability. Atrazine did not affect the concentration of Na+, K+, and Ca2+ ions in maize seedlings to any greater extent; however, some minor changes were observed in some cases. An increase in the stress marker, proline, was found upon exposure to atrazine. The observed effects of atrazine in maize seedlings can be attributed to oxidative stress as revealed by an increase in H2O2 content and higher activities of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) enzymes in atrazine-treated seedlings. The present investigation concludes that atrazine has the potential to adversely affect germination and growth of maize seedlings by inducing oxidative stress that causes increased cell injury and decreased cell viability as well as impairs the concentration of light-harvesting pigments.

This paper presents the Hybrid Scalable-Minimized-Butterfly-Fat-Tree (H-SMBFT) topology for on-chip communication. Main aspects of this work are the description of the architectural design and the characteristics as well as a comparative analysis against two established indirect topologies namely Butterfly-Fat-Tree (BFT) and Scalable-Minimized-Butterfly-Fat-Tree (SMBFT). Simulation results demonstrate that the proposed topology outperforms its predecessors in terms of performance, area and power dissipation. Specifically, it improves the link interconnectivity between routing levels, such that the number of required links isreduced. This results into reduced router complexity and shortened routing paths between any pair of communicating nodes in the network. Moreover, simulation results under synthetic as well as real-world embedded applications workloads reveal that H-SMBFT can reduce the average latency by up-to35.63% and 17.36% compared to BFT and SMBFT, respectively. In addition, the power dissipation of the network can be reduced by up-to33.82% and 19.45%, while energy consumption can be improved byup-to32.91% and 16.83% compared to BFT and SMBFT, respectively.

The determination of captopril is proposed using graphene quantum dots produced by the pyrolysis of citric acid and glutathione (GSH-GQDs). Captopril induces both quenching and spectral red-shifting in the photoluminescence from aqueous dispersions of GSH-GQDs. By employing Fe 3+ as mediator (that enables signal quenching of GSH-GQDs), the presence of captopril restored the photoluminescence of quantum dots. Under optimized experimental conditions, the signal quenching from the GSH-GQDs as function of the concentration of captopril showed a linear response range covering three orders of magnitude (10 −6 to 10 −4 mol L −1 ). The proposed approaches were tested by determining captopril in simulated samples and in commercial pharmaceutical formulations. The measurement of either the spectral shifting observed of the GSH-GQDs probe or the photoluminescence switch on/off using GQDs-GSH-Fe 3+ resulted in satisfactory recoveries of captopril, showing the quantitative sensing potential.

This study was designed to find the effect of vitamin E supplementation on growth, serum antioxidant enzymes, and some trace elements in Japanese quail (Coturnix coturnix japonica) under low ambient temperature. A total of 180 day-old Japanese quails were randomly divided into four groups and provided with 0 (group A), 50 (group B), 100 (group C), and 150 IU/kg (group D) vitamin E (dl-α-tocopherol acetate) under an average temperature of 9±0.5 °C for an experimental period of 42 days. The result showed that feed intake per day, body weight, weight gain per day, and feed conversion ratio did not differ significantly between the groups. Serum concentrations of superoxide and glutathione peroxidase were significantly high in birds supplemented with 150 mg/kg of vitamin E. The concentration of aspartate aminotransferase was not significantly affected between the control and treated groups; however, alanine transaminase concentration significantly reduced in group D. Zinc concentration in the blood increased significantly in group D, with no significant effect on copper and manganese between the control and treated groups. Vitamin E at the level of 150 IU/kg of feed improves the blood antioxidant status and zinc concentration, with no effect on the performance traits of quail reared under low ambient temperature.

Protein is the main limiting factor and the second most expensive feed component of poultry ration after energy. In many developing countries, poultry feed prices are consistently increasing because of the dependency on imported soybean meal. In order to decrease the dependency of the poultry feed sector on soybean meal it is necessary to find sustainable alternative protein sources. This review summarises recent findings on the nutritive value of maggot meal, earth worm meal, meal worms and silkworm meal and discusses their potential as an alternative protein source for poultry feed sector.

Three-year field studies were undertaken at Agricultural Research Institute, Dera Ismail Khan, Khyber Pakhtunkhwa Province, Pakistan from 2010-11 to 2012-2013 with the aim of assessing the efficacy of different management techniques on weed growth and yield of chickpea under rain-fed conditions on residual moisture of a previous rice crop. Treatments of the experiment consisted of recommended full and half doses of three herbicides, i.e., Stomp 330E, Dual Gold 960EC and Isoproturon 500EW and the plant extract of Parthenium hysterophorus. Hand weeding treatment was kept as positive control whereas weedy check was included as negative control treatment. The experiment was laid out in a Completely Randomized Block (CRB) design replicated thrice. Parameters of the investigation were weed density, fresh weed biomass, chickpea growth, biological yield and seed yield. The data revealed that the full dose of Stomp 330E proved superior in terms of weed suppression by giving only 84, 69 and 55 weeds m-2 as compared to weedy check for the years 2010-11, 2011-12 and 2012-13, respectively. Likewise, the highest plant height and seed yield were also recorded for Stomp 330E (full dose) during the entire study, which was statistically at par with hand weeding. However, there was a reduction in overall chickpea yield during the second and third years of experimentation resulting from lower average rainfall. The extract of P. hysterophorus followed Stomp 330E in weed suppression, enhancing plant height as well as biological yield and seed yield. Moreover, the result also shows statistically similar results of the extract of P. hysterophorus for all other tested treatments. Based on the findings of the present research, it was found that herbicides and hand weeding showed superior results in terms of all tested parameters. However, both approaches are non-judicious: hand weeding is laborious while herbicides may cause environmental pollution, hence the herbicidal potential of P. hysterophorus needs to be encouraged in order to achieve sustainable weed management and high yield in an eco-friendly manner. RESUMO: Estudos de campo foram realizados ao longo de três anos no Instituto de Pesquisas Agrícolas Dera Ismail Khan, província de Khyber Pakhtunkhwa, Paquistão, entre 2010-11 e 2012-2013, com o objetivo de avaliar a eficácia de diferentes técnicas de manejo no crescimento de plantas daninhas e rendimento do grão-de-bico sob sistema de irrigação pela chuva em umidade residual de cultivo prévio de arroz. Os tratamentos do experimento foram compostos de doses totais e meias doses, conforme recomendação do fabricante, de três herbicidas: Stomp 330E, Dual Gold 960EC e Isoproturon 500EW, além do extrato vegetal de Parthenium hysterophorus. O tratamento com capina foi mantido como controle positivo, enquanto o tratamento sem capina foi incluído como controle negativo. O experimento teve delineamento em blocos completamente casualizados com três repetições. Os parâmetros da investigação foram densidade de plantas daninhas, biomassa fresca de plantas daninhas, crescimento de grão-de-bico e rendimento biológico e de sementes. Os dados revelaram que a dose total de Stomp 330E foi superior em termos de supressão de plantas daninhas, com apenas 84, 69 e 55 plantas daninhas m-2, em comparação com o tratamento sem capina nos períodos de 2010-11, 2011-12 e 2012-13, respectivamente. Da mesma forma, também foram registrados maior altura das plantas e maior rendimento de sementes com o Stomp 330E (dose total) durante toda a duração do estudo - um resultado estatisticamente semelhante ao da capina de plantas daninhas. No entanto, durante o segundo e o terceiro ano do experimento, foi observada redução na produção total de grão-de-bico, proporcional à menor precipitação média. Assim como o Stomp 330E, o extrato de P. histerophorus também suprimiu as plantas daninhas, aumentando a altura das plantas e o rendimento biológico e de sementes do grão-de-bico. Além disso, os resultados obtidos pelo extrato de P. hysterophorus foram estatisticamente semelhantes aos de todos os outros tratamentos testados. Com base nos resultados desta pesquisa, observou-se que a aplicação dos herbicidas e a capina apresentaram resultados superiores em todos os parâmetros testados; no entanto, ambas as abordagens são pouco sensatas: a capina é trabalhosa, ao passo que os herbicidas podem causar poluição ambiental. Por isso, o potencial herbicida de P. hysterophorus precisa ser incentivado para se alcançar um manejo sustentável de plantas daninhas e um alto rendimento de forma ecologicamente correta.

Network-on-Chip (NoC) has emerged as an innovative solution to the communication bottlenecks of the System-on-Chip (SoC) designs. Being an emerging technology, this field requires an extensive research to cope up with the design challenges of the on-Chip networks. In this research work, we have developed and proposed a unified simulation framework named as ENoCTweak for the simulation and analysis of the important parameters such as latency, throughput. energy and power of the NoC system. This framework is mainly an enhanced and updated version of a well-known simulator NoCTweak with additional performance parameters and integration of different NoC components and simulation platforms. Important components from NOCMAP and ReliableNoC simulators are also integrated into the framework of the proposed ENoCTweak simulator. In this platform, we have embedded different mapping algorithms, like Branch & Bound (BB), Simulated Annealing (SA), Segmented Brute-Force Mapping (SBMAP), Branch & Bound based Exact Mapping (BEMAP), and Optimized Near-optimal Mapping (ONMAP) algorithms, in addition to the existing NMAP and Random algorithms. An External Mapping (EXMAP) setup is also developed to evaluate the mapping results of the existing NoC simulation platforms. In addition to the 2D mesh, other topologies like torus and folded torus are implanted to improve the simulation capabilities of the ENoCTweak simulator. Bit energy model along with the CMOS energy models are added to the simulation framework to enhance the characteristic performance of the simulator.

Laundry detergents, a mixture of different compounds, are used as washing agents in houses and cleaning agents in institutions and industries. As a result, industrial and domestic wastewater usually contains detergent contamination in variable amount. In many developing countries, untreated municipal and industrial wastewater is used for irrigation of crops. There is a possibility that laundry detergents and their ingredients present in irrigation water may affect plant growth as reported in several plant species. However, studies on the effects of laundry detergents on important cereal crops like maize can rarely be found in literature. Therefore, the present study was conducted to evaluate the effects of two commonly used commercial laundry detergents on germination, root-shoot length, fresh biomass, leaf number, leaf width, cell viability, cell injury, light-harvesting pigments, protein contents, and ion concentration in maize (Zea mays L.) seedlings. The obtained results revealed that both the detergents in the tested concentration range (1–500 mg L−1) did not significantly affect seed germination in maize. Similarly, shoot growth, leaf number, and leaf width were not significantly affected by detergents, while in the case of root, one detergent promoted root growth while the other one inhibited it. Both the detergents caused a slight increase in total soluble proteins, and this effect was significant at the highest tested one or two concentrations of detergents (100 and 500 mg L−1). Chlorophylls a and b and total carotenoids were very sensitive to detergent stress and significantly reduced at detergent concentration above 1 or 10 mg L−1. Both the detergents caused an increased cell leakage and reduced cell viability, and in most cases, this effect was statistically significant at detergent doses above 10 mg L−1. Exposure to detergents caused an increased accumulation of Na+, K+, and Ca2+ in maize seedlings. It can be concluded that detergents present in irrigation water at higher concentrations can adversely affect maize by impairing light-harvesting pigments and cell viability.

The determination of kanamycin sulfate was made indirectly by measuring its effect on photoluminescent amino functionalized graphene quantum dots (GQDs-amino) associated with gold nanoparticles (AuNPs) that were produced by the reduction of AuCl4 with NaBH4 in an aqueous dispersion of GQDs-amino (obtained by the pyrolysis of citric acid and glutathione) also containing the cationic surfactant CTAB. The AuNPs-GQDs-amino-CTAB system presents a suppressed photoluminescence that is amplified in the presence of kanamycin. Under optimized experimental conditions, the photoluminescence amplification of the nanomaterial system showed a linear response as a function of kanamycin concentration, covering three orders of magnitude (10−7 to 10−5 mol L−1). The use of solid phase extraction with a cartridge packed with aminoglycoside selective molecularly imprinted polymer ensured selectivity in determinations made on yellow-fever vaccine and veterinary pharmaceutical formulations. The analytical results were statistically similar to those obtained with an HPLC-based fluorescence method (after chemical derivatization). The proposed method is a simple, sensitive and selective approach that does not involve the use of toxic reagents employed for chemical derivatization of aminoglycoside antibiotics.

Both air and water are fundamental and irreplaceable resources for living organisms and their environment. In the last few decades, rapid growth in population, industrialization, and expansion of human activities resulted in an enormous increase in pollution. For quantification of different classes of pollutants like metals, anions, and organic pollutants (pesticides, hormones, oil and grease etc.), in both water and—at lower concentrations—air, many analytical methods have been developed. The modern analytical quantification methodologies, improvement in already existing methods and in parallel sample pretreatment enabled researchers to determine these pollutants selectively at trace and ultra-trace levels in different environmental compartments. This chapter presents a comprehensive summary on hazardous effects due to the presence of different pollutants for humans and ecosystems and different analytical tools for quantification of these pollutants.

In this paper, we propose an optimized, search based near-optimal mapping heuristic, named as ONMAP for mapping real time embedded application workloads on 2D based on-chip interconnection network platforms. ONMAP exploits NMAP, a well-known and fast nearest neighbor heuristic algorithm by using the modular exact optimization method. The proposed hybrid algorithm minimizes the on-chip inter-processor communication energy consumption and optimizes the interconnection network performance parameters. The algorithm inherits the constructive search based heuristic nature of the NMAP algorithm, as well as the property of exact optimization for mapping embedded applications on the target communication architecture. To verify the efficiency and effectiveness of the algorithm, we have compared the proposed algorithm with NMAP and random mapping algorithm under similar simulation environments and traffic conditions. The mapping results of the exemplary real world applications such as VOPD, PIP, MPEG4, MWD, MMS and WiFi-80211arx indicate that ONMAP algorithm is more efficient than its competitors for most of the performance parameters of the on-chip network designs. The algorithm successfully optimized the energy consumption, up to 20 % and 26% in comparison to NMAP and random algorithms, respectively. Similarly, the cost is optimized up to 10% and 60% as compared to NMAP and random mapping algorithms, respectively.

This experiment investigated the effect of a supplementary dietary source (flaxseed) on egg yolk cholesterol contents and fatty acid profile. Flaxseeds at three different levels (5, 10, and 15%) were supplemented to 84 Rhode Island Red × Fayoumi cross layers during 21–24 weeks of age. The birds were divided randomly into four groups. Flaxseeds were supplemented in the diet at the level of 5% (FS-5), 10% (FS-10), and 15% (FS-15), and one group served as the control (FS-0). Cholesterol content of eggs was not significantly affected by flaxseed. The amount of monounsaturated fatty acids was significantly decreased with the increase in the flaxseed level, and the highest reduction was observed in FS-15. The highest total polyunsaturated fatty acid (PUFA) and total omega-3 PUFA were recorded in FS-15. These findings reflect that unsaturated healthy fatty acid content in poultry eggs can be increased with dietary supplementation of flaxseed.

The present study was conducted to investigate the quality and efficacy of commercially available preparations of tylosin and doxycycline available in the local market at Peshawar for poultry. In vitro and in vivo, tests were conducted to check the quality of these antimicrobial drugs. In vitro quality control test was performed by High performance liquid chromatographic (HPLC) and micro dilution method. In vivo, efficacy of the test drugs was checked in broilers infected with Mycoplasma gallisepticum. Results of HPLC indicated that test drug-2 contains doxycycline hydrochloride within specified limits but contain high quantity of active ingredient (Tylosin tartrate 120%). Recovery percentage of test drugs (3, 4, 5) were below the pharmacopoeial limit, which contained low quantity of tylosin tartrate (85%, 87.5%, 85%) respectively however, percent recovery of doxycycline were in the appropriate limits. All the tested drugs were effective against Mycoplasma gallisepticum and showed minimum inhibitory concentration (MIC) at 1.9μg/ml. The in vivo result indicated that all tested drugs decreased morbidity and mortality in infected chicks. The birds treated with test drugs (3 and 5) showed mortality of 9.5%, which was slightly higher than the other test groups. The current study suggested that there are incidences of substandard drugs in Pakistan and the drug regularity authorities should take strict actions against the manufacturing companies.

The experiment was conducted to evaluate the effect of onion (Allium cepa L.,) on the performance, gut microflora and intestinal histomorphology of broiler chicks. Three hundred and twenty day old broiler chicks (Ross) were randomly divided into four groups as A, B, C and D. Group A served as control without any supplementation, group B, C and D was supplemented with onion powder at the rate of 1.5, 2 and 2.5g/kg of feed respectively. Supplementation of onion significantly (P

The determination of l -thyroxine is proposed based on the photoluminescence quenching effect caused on the l -cysteine modified ZnS quantum dots ( l -cysteine ZnS QDs) aqueous dispersion. Under optimum conditions, the analytical response followed a Stern–Volmer model and the experimental conditions were adjusted to enable a robust and reproducible photoluminescence signal. The linear response observed in the quantum dots aqueous dispersion covered the l -thyroxine concentration from the LOQ (2.0×10−8 mol L−1) to 4.0×10−6 mol L−1. The approach was tested in the determination of l -thyroxine in pharmaceutical formulations used to treat patients with thyroid gland disorder. The percent recoveries in controlled samples were between 93.3 and 103%. Analyte fortified saliva was also evaluated as a possible sample for l -thyroxine monitoring of a patient under treatment. It was identified a static type of photoluminescence quenching caused by l -thyroxine.

A new analytical method for mercury speciation in offshore petroleum produced water samples (PW) was developed using the combination of extraction (assisted by ultrasound in the presence of surfactant) and distillation before propylation and determination by gas chromatography cold vapor atomic fluorescence spectrometry (GC-CV-AFS). Ultrasonic (US) treatment (40 min) and the use of Triton X-114 (at 0.5% w/v at pH 3) improved recoveries during the distillation used to separate mercury species from the interfering PW matrix (rich in dispersed oil and salt). Recoveries as high as 92% (Hg2+), 87% (CH3Hg) and 86% (CH3CH2Hg) were achieved. Conditions were adjusted to minimize artifact formation during the samples treatment process in systems containing the major PW matrix components. The method detection limits were 5.0, 8.0 and 11.0 pg L- 1 respectively for Hg2+, CH3Hg and CH3CH2Hg. The use of matrix matched standards (containing mineral oil at 40 mg L−1 and NaCl at 30 g L−1) improved accuracy of the method that was successfully applied for the analysis of four different PW samples, obtained from off-shore operations, with Hg2+ and CH3Hg detected at the ng L−1 level.

Organic acids can be replaced as effective feed additives with antibiotics. Organic acids and their salts have the potential to retard the development of pathogens in the diets and thus maintain the microbial equilibrium in the gastrointestinal tract. In this study, 225 day-old broiler chicks were used for a period of 21 days in order to examine the effect of different levels of organic acids (OA) on performance of broiler. The following parameters: feed intake, water consumption, weight gain, feed conversion ratio (FCR), total Salmonella and E. coli count, weight of visceral organs and length of intestine were studied during starter phase. The experimental chicks were divided into five groups (n=5, 15 birds/replicate). The chicks in control group OA-0 were offered clean drinking water having no organic acid while those in group OA-1, OA-1.5 and OA-2 were given 1, 1.5 and 2ml of organic acid blend. Each litter of drinking water contained citric acid 80g, lactic acid 52g, phosphorous 92g, copper sulphate 10g, respectively. Organic acid (2ml/L) supplementation significantly (p

This study evaluated the growth, carcass characteristics and meat quality of indigenous rabbits in northern Pakistan. Weaned rabbits (age 35 days, weight 323 g) of four distinct phenotypes (white, black and white, brown and black) were fed four experimental diets: alfalfa hay (AH), berseem fodder (BF), BF supplemented with low-level concentrate (50 %; LLC) and high-level concentrate (75 %; HLC). Each experimental diet was fed to 48 rabbits, 12 of each phenotype, in a randomized complete block design. The duration of the experiment was 55 days, including 1 week of adaptation. Rabbits fed the BF and AH diets had poor body weight gain (P

Present study explored the potentials of medicinal plants (Aloe barbedensis, Pimpinella anisum, Berberis lycium, Trigonella foenum-graecum, Allium sativum) mixture in broiler chicks at a ratio of 1:3:1:2:1, respectively. For this purpose 240 chicks were randomly assigned into four major groups, namely; A, B, C and D. Each group was further divided into two subgroups with three replicates of 10 chicks each. One of the subgroups was vaccinated against Newcastle disease (ND), Infectious bronchitis (IB) and Infectious bursal disease (IBD) according to locally adopted vaccination schedule keeping the other subgroup as non vaccinated control. Experimental birds in groups A, B, and C were provided with mentioned infusion @ 20, 10 and 5ml per liter of drinking water while group D was maintained as control. Relevant data were recorded throughout the experiment and or at the termination of the experiment and subjected to statistical analysis. Significantly low mean feed intake (3258.3g) and better FCR (1.87) was recorded in group A. Other parameters like weight gain (1739.7g), antibody titer against ND (7.1), IBD (3300.5) and high density lipoprotein (71.6 g/dl) were significantly increased in chicks from group A. Similarly, blood cholesterol (145.6 g/dl), triglyceride (145.8 g/dl) and low density lipoprotein (57.5 g/dl) were significantly reduced in group A. Overall vaccinated group had higher (P

Milk thistle was added in aflatoxin B1 contaminated poultry feed to investigate and compare its hepatoprotective effects with a commercial toxin binder. Two hundred and forty, day-old broilers were randomly allocated into four major groups A, B, C and D. Group A was kept as control, having aflatoxin free feed, while group B was fed aflatoxin contaminated feed, group C was raised on aflatoxin contaminated feed with toxin binder “Mycoad” @ 3g/kg of feed, while group D was provided aflatoxin contaminated feed along with milk thistle @10g/kg of feed. Aflatoxin B1 was present at the level of 80 µg/kg feed during the first week and 520 µg/kg feed in the remaining experimental period. Serum total protein was significantly (P

Buffaloes usually maintain higher body condition and do not produce milk at the cost of their own body reserves under tropical conditions. The mobilization of body reserves for fulfilling the demands of lactation has been extensively studied in dairy cows while limited work is available on this aspect in dairy buffaloes. Therefore, the present study was conducted to examine variations in milk fatty acid profiles with body condition in Nili-Ravi buffaloes. A total of 24 Nili-Ravi buffaloes within 60 days after parturition, were selected from a private dairy farm in the district of Peshawar. All animals consumed the same diet during the experimental period. A total of 576 raw milk samples were collected for laboratory analysis. The study continued up to 6 months during 2008. Body condition score (BCS), milk yield and composition were recorded once a week. Means for milk fatty acid profile were compared for various levels of BCS. The mean milk yield and fat content were 9.28 kg/d and 5.36%, respectively. The total saturated fatty acids (SFA) were 64.22 g/100 g and the unsaturated fatty acids (UFA) were 35.79 g/100 g. Of the SFA the highest amount was recorded for , followed by , and . The total sum of hypercholesterolemic fatty acids (HCFA, , and ) was 43.33 g/100 g. The concentrations of UFA were greater for moderate BCS followed by poor and highest BCS while SFA showed the opposite trend. The correlation analysis showed that milk yield was negatively affected by BCS and milk fat positively affected, though non-significantly. The present study suggests that Nili-Ravi dairy buffaloes produce similar milk to dairy cows regarding availability of cardioprotective fatty acids, with the highest concentration of . Two HCFA ( and ) were associated with higher body condition. Buffaloes with moderate body condition yielded milk containing healthier fatty acids.

This paper reports the decline in milk production of buffaloes after getting conceived. The experimental buffaloes were selected in NWF province of Pakistan. Complete milk yield records for 48 weeks of lactation were obtained for 465 pregnant and 179 nonpregnant buffaloes. Model-1 to 3 were used to find out the factors affecting milk yield reduction due to pregnancy. Model 4 was used to modulate milk yield reduction with the onset of pregnancy at medium sized private farms comprising lactation records of 40 buffaloes. The data indicate that post-conception reduction in milk yield was earlier in the buffaloes that conceived during 11-28 weeks of lactation, followed by those conceived during 29-36 and 37-48 weeks of lactation respectively. Noticeable reduction in milk yield was found during 3rd, 5th and 6th month of pregnancy in the animals conceiving at earlier, mid or later stages of lactation. Initially the milk yield in pregnant animals increased up to 2 months post-conception and then decreased at an almost constant rate. The reduction was visible after 5th week post-conception. The decline in milk with advancement pregnancy was slight up to a point which we declared as joining point; thereafter the decline was much greater.

The onset of pregnancy may be associated with hormonal changes and decline in milk yield of buffaloes. To investigate this, forty lactating buffaloes from 1st to 23rd weeks post-conception were selected. The animals were assigned to three treatments: PRT, PRS, NPRT and three milk yielding groups HMY, 66 to 75 l/week, n = 12; MMY, 56 to 65 l/week, n = 16; LMY, 46 to 55 l/week, n = 12). Milk samples were collected on alternate weeks and analyzed with ultrasonic milk analyzer. EIA was used for milk progesterone concentrations. Group means were compared and correlation analysis was conducted. Progesterone concentrations increased in almost similar pattern with the advancing weeks post-conception. The high and low yielder showed greater progesterone concentrations in the supplemented than the animals on traditional ration (P < 0.001). Progesterone concentrations correlated positively with fat (%), negatively with milk yield, protein (%) and lactose (%). Decline in milk yield became drastic when progesterone concentrations rose above 6.44 ng/ml. The pregnant animals on traditional ration exhibited a sharper decline in milk yield with the increasing progesterone concentrations as compared to pregnant animals with supplemented ration. It is concluded that concentrates supplementation induced a raise in progesterone levels. Progesterone concentrations and milk yield showed an inverse relationship.

Buffalo are a major source of milk production, contributing 12.1% in the World and 38.0% in Asia. The buffaloes are kept under peri-urban farming systems to produce milk for urban populations. Breeding is delayed in these herds to get more economic benefit because farmers believe that the pregnancy decreases milk production. The lactation milk value has been studied in this paper as an economic indicator. Complete milk yield records of 3,304 buffaloes was collected from a group of state farms. Economic traits including lactation yield, lactation length, calving interval (CI), dry period and milk yield per day of calving interval (MYPDCI) were derived from the data. The animals were grouped according to parity number (1-3), service period (Gl to G4, conceiving during 300 days post calving) and yield levels (HMY>2,500; MMY 2,001-2,500; and LMY 1,500-2,000 liters/ lactation). To study the effect of pregnancy on milk composition a research trial was conducted at a medium size private dairy farm, using forty lactating buffaloes of three yield levels and four service period groups, as described already. Milk was sampled on alternate weeks and analyzed for fat and protein contents (%). For quantifying the value of milk produced during a lactation period, the value corrected milk (VCM) was determined and converted to lactation milk value (LMV). Group means were compared for various parameters. Highest milk yield (2,836.50±15.68 liters/lactation) was recorded in the HMY animals of G4 group while lowest milk yield of 1,657.04±18.34 liters/lactation was found in LMY of G1. Lactation was significantly increased with the extending of service period. The shortest dry period was recorded in HMY, parity 1, Gl animals and the longest in parity 2, MMY, G4.The CI was shortest in HMY, parity 1, and Gl animals and longest in LMY, parity 3, G4 buffaloes. The HMY, parity 2, Gl buffaloes showed the highest MYPDCI and the lowest value was recorded (6.53±0.17 vs. 2.76±0.04 liter/day) for LMY, parity 1, G4 buffaloes. The VCM decreased with the delayed conception. This decreasing trend was higher in respect of the total yield but decrease in the VCM was smaller due to the increasing levels of fat and protein in the milk. The gap between the various production classes was reduced based on the VCM as compared with the yield per day of CI. LMV showed a consistent decline with extending service period in all three production groups. The study suggests that CI increased with delayed conception, showing a consistent trend in the low, moderate and high yielding buffaloes. There was a coherent declining pattern of milk yield with delaying conception, associated with prolonged CI. An animal conceiving at a later stage of lactation showed a decline in financial returns of 24 to 27% compared with those conceiving earlier.

This research was conducted to investigate the effect of supplementation of zinc (Zn) and ascorbic acid (AA) in heat-stressed broilers. A total of 160-day-old broiler chicks of approximately the same weight and appearance were divided into four treatment groups (control, T1, T2, and T3). Control group was fed a standard diet without any supplementation. T1 was supplemented with Zn at the rate of 60 mg/kg of feed, T2 was supplemented with 300 mg/kg of feed AA, and T3 was supplemented with combination of Zn and AA. From week 3 to 5, heat stress environment was provided at the rate of 12 h at 25 °C, 3 h at 25 to 34 °C, 6 h at 34 °C, and 3 h at 34 to 25 °C daily. The results revealed that feed intake, body weight and feed conversion ratio (FCR), and weight of thymus, spleen, and bursa of Fabricius improved significantly (P < 0.05) in T3 compared to the other treatments. Antibody titer against Newcastle disease (ND), infectious bursal disease (IBD), and infectious bronchitis (IB) increased significantly (P < 0.05) in T2 and T3 groups. However, total leucocytes count, lymphocytes, and monocytes increased (P < 0.05) in all treated groups compared to control. The results indicated that the supplementation of Zn or AA alone or in combination improved the performance and immune status of broilers reared under heat stress.

PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO/PROJETO Recentemente, os nanocristais semicondutores, também conhecidos como pontos quânticos, tornaram-se muito atrativos em abordagens de detecção por fotoluminescência devido as suas propriedades ópticas peculiares, tais como fluorescência intensa e com perfil estreito, comprimento de onda máximo ajustável através do controle do tamanho das partículas e maior fotoestabilidade em comparação com os corantes orgânicos convencionais. As nanopartículas sintetizadas foram avaliadas como sondas fotoluminescentes (na forma de dispersão aquosa) para a determinação de captopril, histamina, canamicina e tiroxina (analitos não fotoluminescentes na temperatura ambiente) evitando o uso de procedimentos complexos de derivatização química e permitindo quantificações de forma simples e com sensibilidade. Nanopartículas de CdTe modificadas com o ácido tioglicólico (TGA) e com o ácido 2-mercaptopropiônico (2MPA) e também nanopartículas de ZnS modificadas com L-cisteína foram sintetizadas pela abordagem em fase aquosa coloidal. Estas foram caracterizadas usando métodos microscópicos e espectroscópicos adequados. A fotoluminescência da nanopartícula 2MPA-CdTe foi consideravelmente mais intensa quando na presença de captropil. Sob condições ótimas, o modelo de calibração (isoterma de ligação de Langmuir) foi linear até 4,8 x 10-4 mol L-1 com constante de equilíbrio de ligação de 3,2 x 104 L mol-1 e limite de detecção (LOD) de 6,2 x 10-6 mol L-1 (1,3 (micro)g mL-1). Aplicações em soro sanguíneo humano fortificado com captropil e em formulações farmacêuticas foram demonstradas. A fotoluminescência das nanopartículas de TGA-CdTe foi reduzida (supressão) após adição de diferentes concentrações de histamina seguindo o modelo de Stern- Volmer. A resposta linear cobriu uma faixa de concentração até 5,7 x 10-4 mol L-1, com LOD de 9,6 x 10-6 mol L-1 (1,1 (micro)g mL-1). A abordagem proposta foi utilizada para determinação de histamina em carne de atum. Já a presença de aminoglicosídeos aumentou a fluorescência das nanopartículas de TGA-CdTe (seguindo o modelo da isoterma da adsorção de Langmuir). A kanamicina foi o aminoglicosídeo escolhido para estudar o efeito do aumento da intensidade da fotoluminescência das nanopartículas de TGA-CdTe disperso em solução aquosa. A faixa linear estendeu-se até 8,2 x 10-7 mol L-1 com LOD de 2,5 x 10-8 mol L-1 (14,2 ng mL-1). As constantes de ligação entre diversos aminoglicosídeos e TGACdTe foram calculadas e indicou que existe uma relação entre o número de grupos amino primários disponíveis e o aumento da luminescência. Essa abordagem foi aplicada com sucesso para a análise de amostras de leite e água de riacho, ambos fortificados com kanamicina, usando procedimento de extração em fase sólida com um polímero impresso molecularmente (MIP). A intensidade da fotoluminescência da nanopartícula cisteína-ZnS em solução contendo brometo de cetiltrimetilamônio (CTAB) foi reduzida (quenched) após adição de tiroxina. A redução total do sinal (quenching) seguiu o modelo de Stern-Volmer com resposta linear até 4,0 x 10-6 mol L-1 de concentração do analito, o LOD foi 6,2 x 10-8 mol L-1 (48,3 ng mL-1). A dispersão aquosa da cisteína-ZnS foi usada como sonda óptica para a determinação de tiroxina em formulações farmacêuticas e em saliva humana fortificada com analito. Recently, semiconductor nanocrystals, also known as quantum dots, have become very attractive for photoluminescence based sensing approaches due to their unique optical properties like intense photoluminescence with narrow profile, maximum wavelength adjustable by the control of particle size and higher photostability in comparison of conventional organic dyes. Different synthesized nanoparticles were evaluated as photoluminescent probes (as aqueous dispersions) for the determination of captopril, histamine, kanamycin and thyroxine (nonphotoluminescent analytes at room-temperature) avoiding the use of complex chemical derivatization procedures and enabling simple and sensitive quantifications. Thioglycolic acid (TGA) and 2-mercapoprionic acid (2MPA) modified CdTe nanoparticles and L-cysteine modified ZnS nanoparticles were synthesized via the colloid aqueous phase route. Their characterization was made using proper microscopic and spectroscopic methods. The emission intensity of 2MPA-Cdte is greatly enhanced in the presence of captopril. Under optimum conditions, the calibration model (Langmuir binding isotherm) was linear up to 4.8 x 10-4 mol L-1 with equilibrium binding constant of 3.2 x 104 L mol-1 and limit of detection (LOD) of 6.2 x 10-6 mol L-1 (1.3 (micro)g mL-1). Applications in captopril fortified human serum and in pharmaceutical formulations were demonstrated. The photoluminescence of TGA-CdTe nanoparticles was quenched by histamine in a concentration dependent manner (Stern-Volmer model). The linear response covered the concentration range up to 5.7 x 10-4 mol L-1 with LOD of 9.6 x 10-6 mol L-1 (1.1 (micro)g mL-1). The proposed method was used for the analysis of tuna fish. The presence of aminoglycosides enhanced the photoluminescence of the TGA-CdTe nanoparticles (following a Langmuir binding isotherm model). Kanamycin was used as a model aminoglycoside in order to study its effect on the photoluminescence enhancement of TGA-CdTe quantum dots dispersed in aqueous solution. The linear range extended up to 8.2 x 10-7 mol L-1 with LOD of 2.5 x 10-8 mol L-1 (14.2 ng mL-1). Binding constants were calculated for several aminoglycosides indicating that there is a relationship between the number of available primary amino groups and the increasing in photoluminescence. This approach was successfully applied for determination of kanamycin fortified milk and in stream water samples after solid phase extraction using a molecular imprinted polymer produced using a kanamycin template. The photoluminescence intensity of cysteine-ZnS in solution containing cetyltrimethyl ammonium bromide (CTAB) was quenched by thyroxine. The overall quenching followed a Stern-Volmer model with linear response coveing an analyte concentration range up to 4.0 x 10-6 mol L-1. LOD was 6.2 x 10-8 mol L-1 (48.3 ng mL-1). The aqueous dispersion of cysteine-ZnS was used as optical probe for the determination of thyroxine in pharmaceutical formulations and in analyte fortified human saliva.

Photochemical derivatization is proposed for the spectrofluorimetric determination of tetrabenazine (TBZ). A central composite design was used to adjust experimental conditions (60 min of UV in a 0.45 mol L −1 NaOH solution) enabling the improvement of the analyte signal-to-blank ratio of one order of magnitude, when compared to the TBZ original fluorescence. Limit of quantification was 4.7 × 10 −8 mol L −1 but the detection power can be improved at least 10 times using solid phase extraction that also allows the separation of the analyte from matrix components, enabling the analysis of biologic fluids. Linear range covered at least three orders of magnitude. The combined uncertainty of the determination (at a 5 × 10 −6 mol L −1 ) was 16%. Recoveries of TBZ in the analyses of a pharmaceutical formulation were in agreement with the ones obtained using a HPLC method. Recovery in saliva (5 × 10 −7 mol L −1 of TBZ) was 90 ± 3% ( n = 3). The procedure minimizes the use of toxic chemical derivatization reagents and the generation of hazardous waste.

Th e changes in the composition of milk with advancing pregnancy were investigated in Nili-Ravi dairy buff aloes. Forty lactating buff aloes were used, within 2-3 months postpartum. Th e animals were grouped as high, moderate, and low yielders; synchronized for estrus; and inseminated artifi cially. Milk yield was recorded daily and sampled fortnightly for analysis. Th e data were analyzed using the univariate weighted mean and general linear model. Decline in milk yield became signifi cant aft er the 8th week post-conception. Th e high yielders had the lowest fat contents. Milk fat increased signifi cantly during succeeding weeks post-conception. Th e highest fat level (8.5%) was observed in week 22. Th e solid-not-fat (SNF) was higher during the initial 8 weeks. Protein concentration declined with advancing pregnancy. Th e mineral contents were lower up to 8 weeks and increased later. It was concluded that milk fat concentrations increased linearly from week 2 to 22, while protein showed the opposite pattern in dairy buff aloes. SNF and lactose initially decreased up to week 14 but increased later on. Th is study suggests that milk composition from dairy buff aloes changes with advancing pregnancy, making it suitable for various types of human consumers.

A photoluminescent probe for the determination of captopril is proposed based on the enhancement of luminescence from 2-mercaptopropionic modified CdTe quantum dots (2-MPA-CdTe QDs). Under optimum conditions, the calibration model (the Langmuir binding isotherm) was linear up to 4.8 × 10−4 mol L−1 with equilibrium binding constant of 3.2 × 104 L mol−1 and limit of detection (xb + 3 sb) of 2.7 × 10−7 mol L−1 (59 ng mL−1). The approach was tested in the determination of captopril in pharmaceutical formulations and the results were in agreement with the ones obtained using reference method. The possible mechanism of interaction is also investigated by Raman and electronic absorption spectroscopy and dynamic light scattering.

Intense fluorescence from amitriptyline (AMT) was achieved after photochemical derivatization in an acidic aqueous medium (60 min of UV irradiation of solutions containing 0.027 mol L−1 HCl). After the reaction, fluorescence was significantly enhanced enabling the indirect fluorimetric determination of AMT in drugs and in a pharmacopoeia reference material. The limit of quantification (LOQ) was 1.3 × 10−7 mol L−1 and measurement uncertainty was about 6% at the concentrations close to the LOQ and less than 4% at higher concentrations. The mechanism of the photoreaction was proposed based on the identification of the products and on its kinetics. Studies aiming at the determination of AMT in human serum indicate the potential of the approach as a cheap and simple screening procedure for tricyclic antidepressants.

A total of 120 one-day-old broiler chicks (Ross 308) were randomly assigned to 12 pens of 10 birds in a completely randomized design (CRD). In four experimental diets, soya bean meal was replaced with a maggot meal at the rate of 0, 40, 50 and 60% designated as group A, B, C and D respectively. Body weight was significantly higher (p

PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO As nanopartículas semicondutoras (pontos quânticos ou QDs), na forma de dispersões coloidais aquosas, foram usadas como sondas para determinação indireta de flavonóides. As características especiais desses materiais, decorrente do efeito de confinamento quântico alcançado nas estruturas cujas dimensões são da ordem de poucos nm de diâmetro, resultam em propriedades fotofisicas únicas que podem ser alteradas pelo ajuste do tamanho e/ou na modificação da superfície destes nanocristais. Uma vez que os flavonóides não fluorescem naturalmente, nanopartículas de CdS modificadas com ácido 2-mercaptopropiônico (sonda dos QDs de 2MPA-CdS) e de CdTe modificadas com ácido 3-mercaptopropiônico (sonda dos QDs de 3MPA-CdTe) foram sintetizadas em fase aquosa coloidal e usadas para a determinação indireta de rutina (RUT) e de quercetina (QUE) por meio de medição de decréscimo da fotoluminescência das sondas. A utilização dos QDs como sensores na quantificação destes compostos permitiu a realização de medições fotoluminescentes rápidas e simples, sem a necessidade do uso de complexos procedimentos de derivatização química, usulamente indicados para estes casos. Verificou-se, através do modelo de Stern-Volmer, que o sinal fotoluminescente dos QDs de 2MPA-CdS é atenuado pela presença de RUT, e esta supressão de sinal foi proporcional à concentração de analito na dispersões coloidas (faixa de resposta linear entre 0,5 e 4,0 x 10-5 mol L-1), com limite de detecção (LD) de 1,2 x 10-6 mol L-1. Observou-se também que a supressão de sinal fotoluminescente foi uma combinação da contribuição do efeito filtro (devido à absorção de parcial de radiação pelo analito no comprimento de onda de excitação) e de supressão estática (proveniente da ligação e troca de energia entre analito e QDs). A abordagem foi usada na determinação seletiva de RUT em formulação farmacêutica e em amostras simuladas contendo RUT e QUE ou em saliva fortificada com RUT, nesses dois últimos casos foi associando um método a uma separação prévia de componentes por cromatografia de camada fina. A seletividade em relação a outros flavonóides também foi avaliada. A sonda de 3MPA-CdTe QDs foi usada para a determinação de QUE tanto na dispersão original quanto na dispersão organizada por surfactente (brometo de cetiltrimetilamônio ou CTAB). A QUE foi quantificada em meio não organizado e o método aplicado na análise de suplemento contendo QUE e ácido ascórbico e na análise de extratos de cebolas roxa e amarela. A técnica de cromatografia de camada fina foi utilizada com o intuito de separar a QUE de interferentes presentes na cebola. O modelo de Stern-Volmer foi utilizado para estabelecer uma relação linear entre a fotoluminescência medida na dispersão dos QDs e a quantidade de QUE adicioanda na dispersão. A curva analítica cobriu a faixa de concentrações de QUE entre 0,5 a 6,0 x 10-5 mol L-1 com LD de 0,5 x 10-5 mol L-1. Estudos realizados indicaram que a natureza do quenching formado é estático. Finalmente, um estudo sistemático da interação entre diversos flavonóides e o QDs de 3MPA-CdTe foi estudado de modo a se estabelecer a função do surfactante CTAB no processo de interação entre sonda e supressor. Verificou-se maior estabilidade de sinal da sonda neste meio, e interaçōes analito-QDs distintas daquelas obtidas na ausência do surfactante. The semiconductor nanoparticles (quantum dots or QDs), in the form of aqueous colloidal dispersions, were used as probes for the indirect determination of flavonoids. The special characteristics of these materials, due to the quantum confinement effect achieved in structures whose dimensions are of the order of a few nm, in diameter, result in unique photophysical properties that can be changed by adjusting the size and/or by surface modification of these nanocrystals. Since flavonoids do not present natural fluorescence, CdS nanoparticles modified with 2-mercaptopropionic acid (2MPA-CdS QDs probe) and CdTe modified with 3-mercaptopropionic acid (3MPA-CdTe QDs probe) have been synthesized in colloidal aqueous phase and used for indirect determination of rutin (RUT) and quercetin (QUE) by measuring the photoluminescence decreasing from the probes. The use of QDs as probes for the quantification of these compounds has allowed the quick and simple photoluminescence measurements without the need for complex chemical derivatization procedures, usually indicated in these cases. It was found, through the Stern-Volmer model, that the photoluminescence of the 2MPA-CdS QDs is attenuated by the presence of RUT, and such a signal suppression was proportional to the concentration of analyte in colloidal dispersion (linear response range between 0,5 to 4.0 x 10-5 mol L-1), with limit of detection (LOD) of 1.2 x 10-6 mol L-1. It was also observed that photoluminescence suppression was a combination of the contribution of inner filter effect (due to partial radiation absorption by the analyte at the wavelength of excitation) and static supression (from the binding and energy exchange between analyte and QDs). The method was used to the selective determination of RUT in pharmaceutical formulation and in simulated samples containing QUE/RUT and/or saliva fortified with RUT. For these former two samples, thin layer chromatography was used to establish prior separation of components. The selectivity towards other flavonoids was also evaluated. The 3MPA-CdTe QDs probe was used to determine QUE in original dispersion and in dispersion containing surfactant (cetyltrimethylammonium bromide or CTAB). QUE was quantified in a non-organized environment (without surfactant) and the method was applied for the analysis in supplement containing QUE and ascorbic acid and for the analysis of purple and yellow onions. Thin layer chromatography was used in order to separate interfering present in onions. The Stern-Volmer model was used to establish a linear relationship between the photoluminescence measurement of the QDs dispersion and the amount of QUE added into the dispersion. The analytical curve covered the range of concentrations between 0.5 to 6.0 x 10-5 mol L-1 of QUE with LD 0.5 x 10-5 mol L-1. Studies indicate that the nature of formed quenching is static. Finally, a systematic study of the interaction between various flavonoids and CdTe-3MPA QDs was studied in order to establish the CTAB surfactant function in the interaction between probe and quencher. It was observed more signal stability of the probe in this medium, and interactions distinct analyte-QDs from those obtained in the absence of surfactant.

PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTITUIÇÕES COMUNITÁRIAS DE ENSINO PARTICULARES O objetivo do trabalho foi desenvolver métodos analíticos capazes de especiar mercúrio, determinando metilmercúrio (CH3Hg), etilmercúrio (CH3CH2Hg), mercúrio inorgânico (Hg2+, Hg0), em água de produção (AP), e tiomersal (C9H9HgNaO2S), em urina e em efluente de uma indústria farmacêutica. Apesar de existir muitos métodos para quantificar espécies de mercúrio, poucos estudos abordam a especiação em AP, amostras conhecidas por ter altos teores de óleo e sal. Além disso, o uso de nanomateriais, como pontos quânticos de grafeno (GQDs), sozinho ou dopados de nanopartículas de dióxido de titânio (GQDs-TiO2 NPs), foram usados como agentes fotocatalíticos para produzir o mercúrio elementar detectado. As técnicas analíticas utilizadas para a detecção de mercúrio total e para especiação por mercúrio foram espectrometria de absorção atômica com vapor frio em cela multipasso (multipath-CV-AAS) e espectrometria de fluorescência atômica com vapor frio acoplado ao sistema de cromatografia gasosa (GC-CV-AFS). No primeiro trabalho, a foto-degradação do tiomerosal foi alcançada utilizando luz visível e GQDs, obtidos a partir da hidroexfoliação de ácido cítrico e glutationa, como foto-catalisador. O Hg0 gerado (usando condições experimentais ajustadas) foi detectado por multipath-CV-AAS, permitindo a quantificação de tiomersal em concentrações equivalentes a 20 ng L-1, mesmo em amostras complexas como efluentes aquosos da indústria farmacêutica e em urina. A cinética de reação (pseudo-primeira ordem com k = 0,11 min-1) foi determinada. O segundo trabalho relata o método de especiação de mercúrio em AP usando o sistema CV-AAS. Sob condições ajustadas de concentrações de sal e óleo (por diluição e centrifugação), uma alíquota de amostra foi tratada com SnCl2, levando ao Hg0 quantificado como mercúrio inorgânico original. Uma segunda alíquota de amostra foi exposta a UV (sob condições otimizadas) que promoveu a oxidação de CH3Hg a Hg2+, formando Hg2+ que foi posteriormente reduzido, com SnCl2, produzindo o Hg0 referente ao teor total de mercúrio na amostra. O teor de CH3Hg foi obtido pela diferença nos resultados alcançados para as duas alíquotas. O efeito matriz imposto por óleo e sal foram estudados e, apesar de afetar a intensidade do perfil do tempo de mercúrio, a quantificação foi alcançada com sucesso com padrões ajustados (assemelhamento de matriz) combinando quantidades de NaCl e óleo mineral. As medições de condutividade (estimativa de teor de sal) e turbidimétrica (estimativa de teor de óleo) foram feitas para as amostras de PW, a fim de permitir o ajuste adequado da amostra aos padrões correspondentes (contendo óleo mineral a 5 mg L-1 e NaCl a 5 g L-1). O método de adição de analito também foi utilizada e o limite de quantificação foi de 12 ng L-1. The aim of the present work was to develop analytical methods capable of determining mercury species such as methylmercury (CH3Hg), ethylmercury (CH3CH2Hg), inorganic mercury (Hg2+, Hg0), in produced water (PW) and urine, as well as thiomersal C9H9HgNaO2S) in effluent from a pharmaceutical industry and in urine. Despite many methods for quantifying mercury species are reported, few studies address speciation in PW, sample known to have high oil and salt contents. Besides, the use of nanomaterials such as graphene quantum dots (GQDs) alone or decorating titanium dioxide nanoparticles (GQDs-TiO2 NPs) were used as photocatalytic agents to produce the detected elemental mercury. The analytical techniques used for total mercury detection and mercury speciation were multipath cold vapor atomic absorption spectrometry (multipath˗CV˗AAS) and gas chromatography cold vapor atomic fluorescence spectrometry (GC˗CV˗AFS). In the first work, the photo-degradation of thiomersal has been achieved using visible light and GQDs, obtained from hydro-exfoliation of citric acid and glutathione, as catalysts. The generated Hg0 (using adjusted experimental conditions) was detected by multipath-CV-AAS, enabling quantification of thiomersal at values as low as 20 ng L-1 even in complex samples as aqueous effluents from the pharmaceutical industry and in the urine. The reaction kinetic (pseudo-first-order with k = 0.11 min-1 ) was determined. The second work provided a speciation method for mercury in PW using multipath-CV-AAS. Under adjusted salt and oil contents (by dilution and centrifuging), a sample aliquot was treated with SnCl2, leading to the Hg0 quantified as the original inorganic mercury. A second sample aliquot was exposed to UV (under optimized conditions) that promoted oxidation of CH3Hg to Hg2+, which was then reduced, with SnCl2, producing the Hg0 relative to the total mercury content in the sample. The CH3Hg content was obtained by the difference in results achieved for both aliquots. Matrix effects imposed by oil and salt were studied, and although affecting the intensity of the mercury time profile, quantification was successfully achieved by matrix-matched standards containing NaCl and mineral oil.

PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO BOLSA NOTA 10 O presente trabalho teve como objetivo o desenvolvimento de métodos espectroanalíticos capazes de determinar indiretamente analitos de interesse biológico e farmacológico que possuem fraca atividade óptica no UV-vis (no caso, captopril, histamina e sulfato de canamicina). Embora muitos métodos para quantificar esses analitos estejam reportados, muitos dependem da derivatização química do analito, procedimento considerado complexo e trabalhoso para fazer tais analitos absorverem e emitirem no UV-vis. Por isso, a proposta de uso de pontos quânticos fotoluminescentes é interessante, pois permitem, em condições ajustadas, respostas analíticas que proporcionam a determinação indireta dos analitos de interesse em concentrações da ordem de até 10-8 mol L-1. A determinação do captopril foi proposta utilizando pontos quânticos de grafeno aminofuncionalizados com uso de glutationa (GQDs-amino). O captopril induziu a supressão e o deslocamento espectral (para o vermelho) da fotoluminescência da dispersão aquosa dos GQDs-amino. Por outro lado, quando Fe3+ foi usado como um mediador que gera uma supressão da fotoluminescência da dispersão de GQDs-amino, a adição de captopril restabelece a fotoluminescência original dos pontos quânticos. Em condições experimentais ajustadas, a magnitude da supressão ou de deslocamento espectral da fotoluminescência dos GQDs-amino pode ser relacionada com a concentração de captopril. Em ambos os casos, a resposta linearizada abrangeu três ordens de grandeza (10-6 a 10-4 mol L-1). Em contrapartida, a abordagem de restauração do sinal da sonda, previamente suprimida com Fe3+, também se mostrou útil do ponto de vista analítico. As abordagens propostas foram testadas com a determinação de captopril em amostras simuladas e em formulações farmacêuticas comerciais. O deslocamento 10 espectral a partir da sonda GQDs-amino e ativação/desativação da fotoluminescência utilizando GQDs-amino-Fe3+ resultou em recuperações satisfatórias, mostrando o potencial de detecção quantitativo do método. No estudo com a histamina, avaliou-se o comportamento fotoluminescente da dispersão aquosa de GQDs-amino na presença de histamina com interação mediada por diferentes íons metálicos. Os resultados revelaram que uma interação mais forte e seletiva existia na presença de Eu3+, Fe3+ e Cu2+. A sensibilidade das curvas de supressão de fotoluminescência normalizada (Ks) indicou uma interação dez vezes mais forte da histamina com a superfície dos GQDs na presença de Fe3+. A resposta linear observada nos GQDs-amino-Fe3+ (luminescência medida a 345/435 nm) abrangeu a concentração de histamina de 4,3 × 10-7 mol L-1 (limite de quantificação) até 3,2 × 10-5 mol L-1. A dispersão de GQDs-amino-Fe3+ foi usada como sonda na análise de amostras de atum após extração do analito em cartucho fase sólida catiônica. Os resultados analíticos foram estatisticamente semelhantes aos obtidos com um método baseado na cromatografia líquida com detecção fluorimétrica (após derivatização química da histamina). A determinação do sulfato de canamicina foi feita medindoo efeito que ela exerce sobre a fotoluminescência dos GQDs-amino associados às nanopartículas de ouro (AuNPs), que foram produzidas pela redução de AuCl4 com NaBH4 em uma dispersão aquosa de GQDs-amino (obtido pela pirólise de ácido cítrico e glutationa) contendo também o agente tensoativo catiônico CTAB. O sistema AuNPs-GQDs-amino-CTAB apresentou fotoluminescência suprimida, que foi amplificada na presença de canamicina. Sob condições experimentais ajustadas, a ampliação da fotoluminescência do nanomaterial em função da concentração de analito se mostrou linear e abrangeu três ordens de grandeza (10-7 a 10-5 mol L-1). O uso de extração em fase sólida com um cartucho empacotado com um polímero molecularmente impresso (seletivo para aminoglicosídeos) assegurou a seletividade nas determinações de sulfato de canamicina feitas em vacina da febre amarela e em formulações farmacêuticas veterinárias. Os resultados analíticos foram estatisticamente semelhantes aos obtidos com um método baseado em HPLC com detecção fluorimétrica (após derivatização química da canamicina). Os métodos propostos para a quantificação apresentaram procedimento simples, são muito sensíveis e seletivos, não envolvendo uso de reagentes tóxicos empregados para derivatização química. The objective of the present work was the development of spectroanalytical methods capable of indirectly determining analytes of biological and pharmacological interest that present inherent weak optical activity in UV-vis (in this case, captopril, histamine and kanamycin sulfate). Although many methods to quantify these analytes are reported, many of these depend on chemical derivatization, a procedure considered complex and laborious to promote UV-vis absorption and luminescence. Therefore, the proposed use of photoluminescent quantum dots is interesting since they allow, under adjusted conditions, analytical responses that allow the indirect determination of the analytes of interest in concentrations of the order of down to 10-8 mol L-1. The determination of captopril was proposed using graphene quantum dots aminofunctionalized using glutathione as a precursor (GQDs-amino). Captopril induced photoluminescence suppression and spectral red-shift from the aqueous dispersion of GQDs-amino. In contrast, when Fe3+ is used as a mediator, it generates a suppression of the photoluminescence of the GQD-amino dispersion and the addition of captopril restored the original photoluminescence of the quantum dots. In adjusted experimental conditions, photoluminescence suppression of the GQDs-amino, as a function of the captopril concentration, can be related both to the magnitude of the suppression and to the spectral shift. In both cases, the linearized response covered three orders of magnitude (10-6 to 10-4 mol L-1). In contrast, the probe signal restoration of the previously Fe3+ suppressed photoluminescent GQDs, also proved to be analytically useful. The proposed approaches were tested by the determination of captopril in simulated samples and in commercial pharmaceutical formulations. Spectral shift from the GQDs-amino probe and the photoluminescence on/off approach (using GQDs-amino-Fe3+ probe) resulted in satisfactory recoveries, showing the quantitative capability of the method. In the work concerning histamine, the photoluminescent behavior of the aqueous dispersion of GQDs-amino in the presence of this amino acid was studied in function of different interaction mediators (metal ions). The results revealed that strong and selective interaction existed in the presence of Eu3+, Fe3+ and Cu2+. The sensitivity of normalized photoluminescence (Ks) suppression curves indicated a ten-fold stronger interaction of histamine with the surface of GQDs in the presence of Fe3+. The linear response observed in the GQDs-amino-Fe3+ (luminescence measured at 345/435 nm) covered the histamine concentration of 4.3 × 10-7 mol L-1 (quantification limit) to 3.2 × 10-5 mol L-1. The GQDs-amino-Fe3+ was applied as a probe in the analysis of tuna fish samples after solid phase extraction (SPE) of the analyte using a cationic solid phase. The analytical results were statistically similar to those obtained with a method based on liquid chromatography with fluorimetric detection (after chemical derivatization of histamine). The determination of kanamycin sulfate was made by measuring the effect it exerts on the photoluminescence of gold nanoparticles (AuNPs) associated GQDs, that were produced by the reduction of AuCl4 with NaBH4 in an aqueous dispersion of GQDs-amino (obtained by pyrolysis of citric acid and glutathione) also containing the cationic surfactant CTAB. The AuNPs-GQDs-amino-CTAB system showed a suppressed photoluminescence, which was amplified in the presence of kanamycin. Under adjusted experimental conditions, the magnification of the photoluminescence of the nanomaterial as a function of the analyte concentration was linear and covered three orders of magnitude (10-7 to 10-5 mol L-1). The use of solid phase extraction with a cartridge packed with a molecularly imprinted polymer (selective for aminoglycosides) ensured selectivity in the determinations made in yellow fever vaccine and in veterinary pharmaceutical formulations. The analytical results were statistically similar to those obtained with an HPLC based method with fluorimetric detection (after chemical derivatization of kanamycin). The proposed methods for quantification present simple procedure, are very sensitive and selective, not involving the use of toxic reagents used for chemical derivatization.