A Machine Learning App for Monitoring Physical Therapy at Home.

Shoulder rehabilitation is a process that requires physical therapy sessions to recover the mobility of the affected limbs. However, these sessions are often limited by the availability and cost of specialized technicians, as well as the patient's travel to the session locations. This paper presents a novel smartphone-based approach using a pose estimation algorithm to evaluate the quality of the movements and provide feedback, allowing patients to perform autonomous recovery sessions. This paper reviews the state of the art in wearable devices and camera-based systems for human body detection and rehabilitation support and describes the system developed, which uses MediaPipe to extract the coordinates of 33 key points on the patient's body and compares them with reference videos made by professional physiotherapists using cosine similarity and dynamic time warping. This paper also presents a clinical study that uses QTM, an optoelectronic system for motion capture, to validate the methods used by the smartphone application. The results show that there are statistically significant differences between the three methods for different exercises, highlighting the importance of selecting an appropriate method for specific exercises. This paper discusses the implications and limitations of the findings and suggests directions for future research.

Successful Treatment of Canine Sporotrichosis with Terbinafine: Case Reports and Literature Review.

Sporotrichosis occurs worldwide, and the metropolitan region of Rio de Janeiro, Brazil, is a main endemic area, with a large number of human and animal cases in the last 19 years. This mycosis is more frequently described in cats rather than in dogs. There are a limited number of oral antifungal agents for the treatment of sporotrichosis in animals. In this context, the effectiveness of terbinafine in the treatment of sporotrichosis in humans, as well as the promising results of in vitro susceptibility tests, inspired us to use this drug in the therapy of this mycosis in dogs. We reported for the first time the use of terbinafine in the treatment of two dogs with sporotrichosis caused by Sporothrix brasiliensis. Moreover, we provided an overview of therapeutic features of canine sporotrichosis cases reported since the 1960s. One of the dogs presented the fixed cutaneous form of the disease, while the other patient presented hyperemia of the nasal mucosa and respiratory signs only. Terbinafine showed high antifungal activity in vitro against the canine Sporothrix isolates. The dogs were successfully treated with terbinafine, with remission of all clinical signs initially presented. The current reports indicate that this drug can emerge as a therapeutic option for canine sporotrichosis.

A Randomized Clinical Trial Comparing Itraconazole and a Combination Therapy with Itraconazole and Potassium Iodide for the Treatment of Feline Sporotrichosis.

Feline sporotrichosis is an endemic disease with high occurrence in Brazil. Itraconazole (ITZ) remains the drug of choice for treating this disease in cats, despite the increasing reports of therapeutic failure. A controlled, randomized clinical trial was performed on 166 naive cats with sporotrichosis to assess the effectiveness and safety of the combination therapy with ITZ and potassium iodide (KI) compared with ITZ monotherapy. Cats were randomly allocated into two treatment groups: G1-ITZ 100 mg/cat/day-and G2-ITZ 100 mg/cat/day + KI 2.5-20 mg/kg/day. Cats treated in G2 presented 77% more risk of reaching a clinical cure (a positive effect) than those treated in G1, even when controlled by negative predictors. The survival curves of the two treatment protocols indicate that a clinical cure was achieved faster in G2. An increase in the KI dose was necessary in 28 cats due to the persistence of clinical signs. Adverse reactions were equally frequent in both groups and manageable with a temporary drug suspension and/or a hepatoprotective therapy. The combination therapy was associated with a higher cure rate and a shorter treatment time, suggesting that ITZ+KI arises as a better option for treating feline sporotrichosis and should be considered the first-line treatment, especially in the presence of negative predictors.

Data2MV - A user behaviour dataset for multi-view scenarios.

The Data2MV dataset contains gaze fixation data obtained through experimental procedures from a total of 45 participants using an Intel RealSense F200 camera module and seven different video playlists. Each of the playlists had an approximate duration of 20 minutes and was viewed at least 17 times, with raw tracking data being recorded with a 0.05 second interval. The Data2MV dataset encompasses a total of 1.000.845 gaze fixations, gathered across a total of 128 experiments. It is also composed of 68.393 image frames, extracted from each of the 6 videos selected for these experiments, and an equal quantity of saliency maps, generated from aggregate fixation data. Software tools to obtain saliency maps and generate complementary plots are also provided as an open-source software package. The Data2MV dataset was publicly released to the research community on Mendeley Data and constitutes an important contribution to reduce the current scarcity of such data, particularly in immersive, multi-view streaming scenarios.

Predicted Environmental Risk Assessment of Antimicrobials with Increased Consumption in Portugal during the COVID-19 Pandemic; The Groundwork for the Forthcoming Water Quality Survey.

The environmental release of antimicrobial pharmaceuticals is an imminent threat due to ecological impacts and microbial resistance phenomena. The recent COVID-19 outbreak will likely lead to greater loads of antimicrobials in the environment. Thus, identifying the most used antimicrobials likely to pose environmental risks would be valuable. For that, the ambulatory and hospital consumption patterns of antimicrobials in Portugal during the COVID-19 pandemic (2020-2021) were compared with those of 2019. A predicted risk assessment screening approach based on exposure and hazard in the surface water was conducted, combining consumption, excretion rates, and ecotoxicological/microbiological endpoints in five different regions of Portugal. Among the 22 selected substances, only rifaximin and atovaquone demonstrated predicted potential ecotoxicological risks for aquatic organisms. Flucloxacillin, piperacillin, tazobactam, meropenem, ceftriaxone, fosfomycin, and metronidazole showed the most significant potential for antibiotic resistance in all analysed regions. Regarding the current screening approach and the lack of environmental data, it is advisable to consider rifaximin and atovaquone in subsequent water quality surveys. These results might support the forthcoming monitorisation of surface water quality in a post-pandemic survey.

Improving word embeddings in Portuguese: increasing accuracy while reducing the size of the corpus.

The subjectiveness of multimedia content description has a strong negative impact on tag-based information retrieval. In our work, we propose enhancing available descriptions by adding semantically related tags. To cope with this objective, we use a word embedding technique based on the Word2Vec neural network parameterized and trained using a new dataset built from online newspapers. A large number of news stories was scraped and pre-processed to build a new dataset. Our target language is Portuguese, one of the most spoken languages worldwide. The results achieved significantly outperform similar existing solutions developed in the scope of different languages, including Portuguese. Contributions include also an online application and API available for external use. Although the presented work has been designed to enhance multimedia content annotation, it can be used in several other application areas.

Photo2Video: Semantic-Aware Deep Learning-Based Video Generation from Still Content.

Applying machine learning (ML), and especially deep learning, to understand visual content is becoming common practice in many application areas. However, little attention has been given to its use within the multimedia creative domain. It is true that ML is already popular for content creation, but the progress achieved so far addresses essentially textual content or the identification and selection of specific types of content. A wealth of possibilities are yet to be explored by bringing the use of ML into the multimedia creative process, allowing the knowledge inferred by the former to influence automatically how new multimedia content is created. The work presented in this article provides contributions in three distinct ways towards this goal: firstly, it proposes a methodology to re-train popular neural network models in identifying new thematic concepts in static visual content and attaching meaningful annotations to the detected regions of interest; secondly, it presents varied visual digital effects and corresponding tools that can be automatically called upon to apply such effects in a previously analyzed photo; thirdly, it defines a complete automated creative workflow, from the acquisition of a photograph and corresponding contextual data, through the ML region-based annotation, to the automatic application of digital effects and generation of a semantically aware multimedia story driven by the previously derived situational and visual contextual data. Additionally, it presents a variant of this automated workflow by offering to the user the possibility of manipulating the automatic annotations in an assisted manner. The final aim is to transform a static digital photo into a short video clip, taking into account the information acquired. The final result strongly contrasts with current standard approaches of creating random movements, by implementing an intelligent content- and context-aware video.

Identification of Antibiotics in Surface-Groundwater. A Tool towards the Ecopharmacovigilance Approach: A Portuguese Case-Study.

Environmental monitoring, particularly of water, is crucial to screen and preselect potential hazardous substances for policy guidance and risk minimisation strategies. In Portugal, extensive data are missing. This work aimed to perform a qualitative survey of antibiotics in surface- groundwater, reflecting demographic, spatial, consumption and drug profiles during an observational period of three years. A passive sampling technique (POCIS) and high-resolution chromatographic system were used to monitor and analyse the antibiotics. The most frequently detected antibiotics were enrofloxacin/ciprofloxacin and tetracycline in surface-groundwater, while clarithromycin/erythromycin and sulfamethoxazole were identified only in surface water. The detection of enzyme inhibitors (e.g., tazobactam/cilastatin) used exclusively in hospitals and abacavir, a specific human medicine was also noteworthy. North (Guimarães, Santo Tirso and Porto) and South (Faro, Olhão and Portimão) Portugal were the regions with the most significant frequency of substances in surface water. The relatively higher detection downstream of the effluent discharge points compared with a low detection upstream could be attributed to a low efficiency in urban wastewater treatment plants and an increased agricultural pressure. This screening approach is essential to identify substances in order to perform future quantitative risk assessment and establishing water quality standards. The greatest challenge of this survey data is to promote an ecopharmacovigilance framework, implement measures to avoid misuse/overuse of antibiotics and slow down emission and antibiotic resistance.

Canine sporotrichosis: polyphasic taxonomy and antifungal susceptibility profiles of Sporothrix species in an endemic area in Brazil.

Sporotrichosis, a mycosis caused by pathogenic species of the genus Sporothrix, affects diverse species of mammals. Until 2007, Sporothrix schenckii was considered the unique etiologic agent of sporotrichosis. Canine sporotrichosis is a poorly reported disease, and the majority of cases are from Rio de Janeiro, Brazil. There are scarce studies on the characterization of canine isolates of Sporothrix schenckii complex, as well as few antifungal susceptibility data available. The aim of this study was to characterize the clinical isolates of Sporothrix from dogs from Brazil at species level and evaluate their antifungal susceptibility profile. Polyphasic taxonomy was used to characterization at species level (morphological, phenotypical characteristics, and molecular identification). Antifungal susceptibility profiles (amphotericin B, itraconazole, ketoconazole, posaconazole, and terbinafine) were determined using the Clinical and Laboratory Standards Institute broth microdilution method (M38-A2). According to phenotypic identification and molecular analysis, 46 isolates included in this study were identified as S. brasiliensis and one as S. schenckii. Amphotericin B presented the highest minimum inhibitory concentration values, and the other drugs showed effective in vitro antifungal activity. This is the first report of S. schenckii in dogs from Brazil, since S. brasiliensis is the only species that has been described in canine isolates from Rio de Janeiro to date. Nevertheless, no differences were observed in the antifungal susceptibility profiles between the S. brasiliensis and S. schenckii isolates, and it is important to continuously study new canine clinical isolates from Rio de Janeiro, Brazil.

Association between Single Nucleotide Polymorphisms and Endometriosis in a Brazilian Population.

OBJECTIVE: To investigate the association between genetic polymorphisms in candidate genes or candidate regions and the development of endometriosis in Brazilian women. METHODS: A total of 30 women between 25 and 64 years old with a diagnosis of endometriosis participated in the present study, as well as 30 matched control women from the same age group, asymptomatic and without family history of the disease. The patients genotypic and allelic frequencies of polymorphisms in the GREB1 gene (rs13394619) and in the intergenic region at position 7p15.2 (rs12700667) were analyzed and compared. RESULTS: There was no significant difference in the frequency of genotypes for the A > G polymorphism (rs13394619) in the GREB1 gene between the two groups. However, the distribution frequencies of the genotypes for the A > G polymorphism (rs12700667) in an intergenic region on chromosome 7 were different for control patients and for patients with endometriosis, with higher frequency of the AG genotype compared to the GG between patients with the disease (odds ratio [OR] = 3.49; confidence interval [CI] = 1.47-8.26). CONCLUSION: The present study suggests that the polymorphism in the intergenic region of chromosome 7 is associated with the risk of developing endometriosis in a population of Brazilian women from Juiz de Fora.

Mitochondrial disfunction and ROS production are essential for anti-Trypanosoma cruzi activity of ß-lapachone-derived naphthoimidazoles.

Chagas disease is caused by the hemoflagellate protozoa Trypanosoma cruzi and is one of the most important neglected tropical diseases, especially in Latin American countries, where there is an association between low-income populations and mortality. The nitroderivatives used in current chemotherapy are far from ideal and present severe limitations, justifying the continuous search for alternative drugs. Since the1990s, our group has been investigating the trypanocidal activity of natural naphthoquinones and their derivatives, and three naphthoimidazoles (N1, N2 and N3) derived from ß-lapachone were found to be most effective in vitro. Analysis of their mechanism of action via cellular, molecular and proteomic approaches indicates that the parasite mitochondrion contains one of the primary targets of these compounds, trypanothione synthetase (involved in trypanothione production), which is overexpressed after treatment with these compounds. Here, we further evaluated the participation of the mitochondria and reactive oxygen species (ROS) in the anti-T. cruzi action of naphthoimidazoles. Preincubation of epimastigotes and trypomastigotes with antioxidants (α-tocopherol and urate) strongly protected the parasites from the trypanocidal effect of naphthoimidazoles, decreasing the ROS levels produced and reverting the mitochondrial swelling phenotype. The addition of pro-oxidants (menadione and H2O2) before the treatment induced an increase in parasite lysis. Despite the O2 uptake and mitochondrial complex activity being strongly reduced by N1, N2 and N3, urate partially restored the mitochondrial metabolism only in N1-treated parasites. In parallel, MitoTEMPO, a mitochondrial-targeted antioxidant, protected the functionality of the mitochondria in N2- and N3-treated parasites. In addition, the trypanothione reductase activity was remarkably increased after treatment with N1 and N3, and molecular docking demonstrated that these two compounds were positioned in pockets of this enzyme. Based on our findings, the direct impairment of the mitochondrial electron transport chain by N2 and N3 led to an oxidative misbalance, which exacerbated ROS generation and led to parasite death. Although other mechanisms cannot be discounted, mainly in N1-treated parasites, further investigations are required.

Priority pesticides and their degradation products in river sediments from Portugal.

A multiresidue gas chromatography-mass spectrometry method was developed to determine 28 priority pesticides of different chemical families (organochlorine, organophosphorus, triazines, anilides) together with some of their transformation products in river sediment. Ultrasonic, Soxhlet and pressurized liquid extraction (PLE) methods were compared in spiking experiments using acetone:hexane (1:1) followed by alumina solid phase extraction cartridges or in-cell alumina clean-up for PLE. All extraction techniques produced acceptable recoveries for the pesticides under study, although Soxhlet extraction produced the lowest recoveries for 2,4-DDE, trifluralin, lindane, and hexachlorobenzene (<50%) whereas ultrasonic extraction resulted in low recoveries for hexachlorobenzene and lindane (<50%). However, PLE using in-cell alumina clean-up produced an overestimation of more apolar compounds, given the amount of coextracted compounds. Limits of detection at the low microg L(-1)-ng L(-1) levels were obtained with Soxhlet and ultrasonic extraction, while PLE produced higher variability due to the lack of exhaustive clean-up. Given the simplicity of ultrasonic extraction, this method was further employed to determine target compounds in river sediments collected in Portugal. Lindane was detected in practically all samples, followed by trace levels of the pesticides simazine, diazinon, fenitrothion, and parathion-methyl.

Presence and impact of Stockholm Convention POPs in gull eggs from Spanish and Portuguese natural and national parks.

The aim of the present work was to comparatively assess the occurrence and impact of persistent organic pollutants (POPs) in nine natural and national parks from Spain and Portugal using gull eggs (Larus michahellis and L. audouinii) as bioindicators of environmental contamination. Sampling was performed during the breeding season of 2016. Compounds studied include polychlorinated biphenyls (PCBs), organochlorinated pesticides (OC pesticides), perfluorooctane sulfonic acid (PFOS) and polybrominated diphenyl ethers (PBDEs), and were analyzed using mass spectrometric based techniques. The results showed a high contamination by PCBs in all colonies, with total levels ranging from 59 to 1278ng/g wet weight (ww), despite their use is not currently authorized. OC pesticides were also present in all colonies, with a high incidence of 4,4'-DDE in gull eggs at levels up to 218±50ng/g ww in L. michahellis and 760±412ng/g ww in L. audouinii from the Ebro Delta natural park. PBDEs and PFOS were also detected at levels up to 91.7±21.3ng/g ww, which can be attributed to a more recent use. Except for PBDEs, the POP levels in eggs from L. audouinii were higher than in L. michahellis, presumably associated to the fish-based diet of the former. Finally, the effect of POP levels on eggshell parameters (volume, eggshell thickness and desiccation index) were investigated for each colony and gull species in order to evaluate the egg viability and, therefore, the reproduction success.

Predictors of death among cardiac arrest patients after therapeutic hypothermia: A non-tertiary care center's initial experience.

INTRODUCTION AND OBJECTIVES: Therapeutic hypothermia (TH) is recommended for patients with return of spontaneous circulation (ROSC) after cardiac arrest (CA). There is still uncertainty about management, target temperature and duration of TH. In the present study we aim to describe the initial experience of a non-tertiary care center with TH after CA and to determine predictors of mortality. METHODS: During the period 2011-2014, out of 2279 patients hospitalized in the intensive care unit, 82 had a diagnosis of CA with ROSC. We determined predictors of mortality and neurological outcome in comatose patients with ROSC after CA treated by TH. RESULTS: A total of 15 patients were included, mean age 47.3±14 years, 10 (67.0%) male. CA occurred out-of-hospital (n=11; 73.3%) or in-hospital (n=4; 26.7%), in initial shockable (n=10; 66.7%) or non-shockable (n=5, 33.3%) rhythm. The mean time from CA to ROSC (CA-ROSC) was 44.7±36.5 min. All patients met the 24-hour TH target temperature of 33°C. The mean neuron-specific enolase (NSE) level was 93.7±109.0 µg/l. Seven patients (46.7%) were discharged with good cerebral performance and eight (53.3%) died. Patients who survived had lower median age (p=0.032), shorter CA-ROSC (p=0.048), lower NSE levels (p=0.020) and initial ventricular fibrillation rhythm (p=NS). CONCLUSIONS: The effectiveness of TH appears to be related to younger age, shockable initial rhythm and shorter CA-ROSC time. This results indicates some lines of inquiry that should be developed in appropriate prospective studies. The role of biomarkers as predictors of prognosis is an open question, with NSE potentially playing an important role.

Survey of organotin compounds in rivers and coastal environments in Portugal 1999-2000.

In the period from April 1999 to May 2000, organotin pollution, namely butyl and phenyltins, was investigated in coastal and continental waters (46 stations), estuarine sediments (15 stations) and mussels (Mytilus galloprovincialis) (13 stations) throughout Portugal. Sampling points were chosen in areas of specific industrial, agricultural and harbor activities. Butyltins (BTs) were the only tin species identified of which tributyltin (TBT) was found in the whole area. Concentrations of TBT in river water ranged from 3 to 30 ng L(-1) (as Sn), marine sediment ranged from 4 to 12 microg kg(-1) (as Sn), whereas concentrations in mussel tissue ranged from 2.5 to 490 microg kg(-1) (as Sn). Given that some water samples appeared to be contaminated by higher monobutyltin (MBT) and dibutyltin (DBT) concentrations, the role of biological degradation and direct inputs from agricultural and industrial applications areas are discussed. The study compares depleted butyltin pollution in sediments and mussels of the Portuguese coastline associated with antifouling paints with previously reported levels. Inputs in river waters are more related to (i) PVC leaching and (ii) industrial sources, in some cases discharged by municipal wastewaters.

Detection and evaluation of endocrine-disruption activity in water samples from Portuguese rivers.

Water samples (n = 183) from Portuguese rivers were tested for the presence of endocrine disruptors using the recombinant yeast assay (RYA) combined with chemical identification of compounds having endocrine-disruption properties by liquid chromatography coupled to mass spectrometry. Ten selected locations were sampled monthly for a period of 20 months, from April 2001 to December 2002. More than 90% of samples showed either no detectable or low levels of estrogenicity (<0.1 ng/L of estradiol equivalents). The remaining samples (17 in total, 9.3%) showed estrogenicity values ranging from 0.1 to 1.7 ng/L of estradiol equivalents; only two samples showed values greater than 1 ng/L of estradiol equivalents. Most highly estrogenic samples (13 of 17 samples) originated in five sampling sites clustered in two zones near Porto and Lisbon. Chemical analysis detected alkylphenolic compounds (octyl- and nonylphenol plus nonylphenol ethoxylates) in all samples, albeit at concentrations less than 1 microg/L for each compound in 80% of samples. Total analyte concentration exceeded 10 microg/L in only 10 samples, with all but one of those originating from only two sampling sites. In these two locations, a good correlation was observed between the concentrations of octylphenol, nonylphenol, and to a lesser extent, bisphenol A in the samples and their estrogenicity values as calculated by RYA. We conclude that estrogenic activity can be explained by alkylphenol contamination in only these sites; for the remainder, we propose that pesticides and urban waste may be the main factors responsible for estrogenic contamination.

Association between single nucleotide polymorphisms and endometriosis in a brazilian population / Associação de polimorfismos de único nucleotídeo com a endometriose em uma população brasileira

Abstract Objective To investigate the association between genetic polymorphisms in candidate genes or candidate regions and the development of endometriosis in Brazilian women. Methods A total of 30 women between 25 and 64 years old with a diagnosis of endometriosis participated in the present study, as well as 30 matched control women from the same age group, asymptomatic and without family history of the disease. The patients genotypic and allelic frequencies of polymorphisms in the GREB1 gene (rs13394619) and in the intergenic region at position 7p15.2 (rs12700667) were analyzed and compared. Results There was no significant difference in the frequency of genotypes for the A > G polymorphism (rs13394619) in the GREB1 gene between the two groups. However, the distribution frequencies of the genotypes for the A > G polymorphism (rs12700667) in an intergenic region on chromosome 7 were different for control patients and for patients with endometriosis, with higher frequency of the AG genotype compared to the GG between patients with the disease (odds ratio [OR] = 3.49; confidence interval [CI] = 1.47-8.26). Conclusion The present study suggests that the polymorphism in the intergenic region of chromosome 7 is associated with the risk of developing endometriosis in a population of Brazilian women from Juiz de Fora.

Resumo Objetivo Investigar a associação de polimorfismos genéticos em genes candidatos ou regiões candidatas com o desenvolvimento da endometriose em mulheres brasileiras. Métodos Um total de 30 mulheres com diagnóstico de endometriose, com idade entre 25 e 64 anos, participaram da presente pesquisa, bem como 30 mulheres controle, na mesma faixa etária, assintomáticas e sem história familiar da doença. Foram analisadas e comparadas as frequências genotípicas e alélicas de polimorfismos no gene GREB1 (rs13394619) e na região intergênica na posição 7p15.2 (rs12700667) nessas pacientes. Resultados Não houve diferença significativa na frequência dos genótipos para o polimorfismo A > G (rs13394619) no gene GREB1 entre os dois grupos. No entanto, as frequências de distribuição dos genótipos para o polimorfismo A > G (rs12700667) em uma região intergênica no cromossomo 7 foram diferentes entre as pacientes controle e com endometriose, com frequência mais alta do genótipo AG comparado ao GG entre as pacientes com a doença (odds ratio [OR] = 3,49; intervalo de confiança [IC] 95% = 1,47-8,26). Conclusão O presente estudo sugere que o polimorfismo na região intergênica do cromossomo 7 foi associado com o risco do desenvolvimento de endometriose em uma população de mulheres de Juiz de Fora.

Pressurized liquid extraction followed by liquid chromatography-mass spectrometry for the determination of alkylphenolic compounds in river sediment.

A new methodology based on pressurized liquid extraction (PLE) followed by LC-MS is presented for the simultaneous and unequivocal determination of alkylphenol ethoxylates (APEOs) and their degradation products, alkylphenols (APs) and alkylphenoxy carboxylates (APECs), in sediment samples. The protocol, applicable to a full range of APEO oligomers and degradation products, permits the sensitive and selective determination of APEOs (nEO = 1-15), APECs (nEO = 0-1) and APs at low ppb levels (LODs = 1-5 microg/kg) in sediment samples. Optimization of the operational parameters of PLE clearly demonstrates that significant thermal losses of APs occur during extraction at elevated temperatures. The loss of octylphenol (OP) at 100 degrees C was 61.2% and of nonylphenol (NP) 40.0%, whereas other compounds were completely recovered. Thus, to avoid losses due to the volatility of alkylphenols, a low extraction temperature should be applied. The conditions that gave the best results for all target compounds were as follows: extraction solvent mixture, methanol-acetone (1:1, v/v); temperature, 50 degrees C; pressure, 1500 p.s.i.; two static cycles. Using PLE and a subsequent clean-up with solid-phase extraction (SPE), the simultaneous extraction of APEOs, APs and APECs from sediment samples was achieved yielding recoveries >70% and producing low MS background noise. The developed methodology was applied on a routine basis to the analysis of alkylphenolic compounds in sediment samples. APEOs and their persistent degradation products were detected in significant concentrations in sediments from Portuguese rivers, especially at sites situated in the proximity of industrial plants (mainly the textile industry). The total concentration of alkylphenolic compounds (APEOs+APs+APECs) ranged from 155 to 2400 microg/kg. Of all the alkylphenolic compounds, NP comprised 40 to 50% with concentrations up to 1172 microg/kg.

Multicomponent analysis of volatile organic compounds in water by automated purge and trap coupled to gas chromatography-mass spectrometry.

The performance of an automated purge and trap concentrator coupled to gas chromatography-mass spectrometric detection was evaluated by analyzing 40 volatile organic compounds of different chemical families. Compounds chosen defined as toxic for the environment and for human health were selected according to Directive 76/464/CEE. The present work includes: (i) the optimization of the purge and trap conditions, (ii) the establishment of quality parameters and in last instance (iii) the analysis of surface waters. The analytical method consisted of a modification of the EPA Method 524.2 in which water was pumped, via an automated AquaTek 70 Liquid Autosampler to a 25-ml purging device, where samples were purged and trapped in a Tenax or Tenax-Silica and Charcoal column. Afterwards, helium was used to desorb the trapped analytes that flow directly into the GC column. Mass spectrometric analysis was carried out in selected ion monitoring and scan modes to ensure quantification and confirmation of the results. Parameters optimized were the sample volume analyzed, bubbling flow-rate and time and temperature of desorption. Optimal conditions lead to mean recoveries of 80%, limits of detection between 0.002 and 0.1 microg/l, linearity from 0.01 to 2.5 microg/l and maximum standard deviation of 10%, using a Tenax trap. This protocol permitted a high precision and sample throughput and was used to determine volatile organic compounds in surface river, effluents and coastal waters of Portugal, on a routine basis.

Chemometric modeling of main contamination sources in surface waters of Portugal.

Various chemometric data analysis methods, such as principal components analysis, multivariate curve resolution-alternating least squares, parallel factor analysis, and Tucker3, are proposed and compared for the resolution and modeling of main contamination sources in a large environmental data array obtained in an exhaustive environmental monitoring program that examined the quality of surface waters of Portugal. The study covered the analysis of 19 priority semivolatile organic compounds (SVOCs) frequently found in a total number of 644 surface water samples, including 46 different sites from throughout Portugal and corresponding to a period of 14 months, from April 1999 to May 2000. Main contamination sources of the analyzed SVOCs were identified and interpreted according to their chemical composition and according to their resolved geographical and temporal distribution profiles.