Bacterial septicemia and herpesvirus infection in Antarctic fur seals (Arctocephalus gazella) stranded in the São Paulo coast, Brazil.

In August 2021, two juvenile male Antarctic fur seals (Arctocephalus gazella) stranded in the southeastern Brazilian coast and were referred to rehabilitation centers. The animals presented increased body temperature, prostration, respiratory distress and despite treatment died. A necropsy following a standardized protocol was performed, and formalin-fixed tissues were processed for microscopic examination. Samples were screened for morbillivirus, herpesvirus, and Brucella spp. by molecular analyses (PCR, RT-PCR). Bacteriological culture was performed in samples collected from the lungs, trachea, and lymph nodes of both cases. The main histopathologic findings were of infectious nature, including multifocal necrotizing and fibrinous mixed interstitial pneumonia, bronchiolitis, and bronchitis, with intralesional myriad bacteria associated with vascular fibrinoid necrosis. Pseudomonas aeruginosa was isolated from tracheal and lung swabs of Case 1, and Klebsiella oxytoca was found in nostril swabs, tracheobronchial lymph nodes, and lung of Case 2. Gammaherpesvirus infection was detected in both cases, and the sequences retrieved were classified into the genus Percavirus. All tested samples were PCR-negative for Brucella spp. and morbillivirus. We hypothesize that the deficient immunological status in association with starvation predisposed the reactivation of herpesvirus and secondary bacterial co-infections. To the authors' knowledge, this is the first molecular detection of herpesvirus in an Antarctic pinniped. These findings reinforce that Otariid gammaherpesvirus circulating in the Southern Hemisphere are likely endemic in the Arctocephalus genus. This report contributes to the current knowledge of health aspects affecting wild pinnipeds, especially in the poorly studied Antarctic species.

Análisis de los parámetros ecográficos descritos en el estudio del síndrome del túnel del carpo. Una revisión sistemática / Analysis of the echographic parameters described in the study of carpal tunnel syndrome: A systematic review

El síndrome del túnel del carpo (STC) es la mononeuropatía por atrapamiento más frecuente; el diagnóstico se establece mediante pruebas electrodiagnósticas con un número sustancial de falsos positivos/negativos. Presentamos la siguiente revisión sistemática, cuyo objetivo es analizar la literatura más reciente en relación con los parámetros ecográficos descritos para estudiar el STC. Seleccionamos estudios que evaluasen parámetros ecográficos en pacientes con sospecha clínica, siguiendo las recomendaciones del manual Cochrane; incluimos revisiones sistemáticas, metaanálisis, estudios caso-control y de pruebas diagnósticas, valorando estudios retrospectivos y revisiones bibliográficas con buena calidad metodológica. La revisión se hizo de artículos publicados entre 2005-2019. Incluimos 8 artículos (2 revisiones sistemáticas/metaanálisis, 2 estudios caso-control, un estudio de pruebas diagnósticas, 2 revisiones literarias y un estudio retrospectivo). Los parámetros analizados fueron el área de sección transversa del nervio mediano, el índice muñeca-antebrazo, el índice entrada-salida, el rango de adelgazamiento del nervio mediano, el abombamiento del retináculo flexor y la vascularización/movilidad. La evidencia actual permite afirmar que la ecografía tiene utilidad en el cribado del STC.(AU)

Carpal tunnel syndrome (CTS) is the most common entrapment mononeuropathy; the diagnosis is established by electrodiagnostic tests with until 34% of false positives/negatives. We present the following systematic review which objective is to analyze the most recent literature related to the ultrasound parameters described to study CTS. We selected studies that evaluated ultrasound parameters in patients with clinical suspicion following the Cochrane manual's recommendations. We include systematic reviews, meta-analyses, case–control studies and diagnostic tests, evaluating retrospective studies and bibliographic reviews with proper methodological quality. Articles published between 2005 and 2019. We included eight articles (two systematic reviews/meta-analyses, two case–control studies, one diagnostic test study, two literature reviews, and one retrospective). The parameters analyzed were cross-sectional area, wrist–forearm index, entry–exit index, thinning range, palmar bowing of the flexor retinaculum, and vascularity/mobility. Current evidence allows us to affirm that ultrasound is useful in screening for CTS.(AU)

[Analysis of the echographic parameters described in the study of carpal tunnel syndrome: A systematic review]. / Análisis de los parámetros ecográficos descritos en el estudio del síndrome del túnel del carpo. Una revisión sistemática.

Carpal tunnel syndrome (CTS) is the most common entrapment mononeuropathy; the diagnosis is established by electrodiagnostic tests with until 34% of false positives/negatives. We present the following systematic review which objective is to analyze the most recent literature related to the ultrasound parameters described to study CTS. We selected studies that evaluated ultrasound parameters in patients with clinical suspicion following the Cochrane manual's recommendations. We include systematic reviews, meta-analyses, case-control studies and diagnostic tests, evaluating retrospective studies and bibliographic reviews with proper methodological quality. Articles published between 2005 and 2019. We included eight articles (two systematic reviews/meta-analyses, two case-control studies, one diagnostic test study, two literature reviews, and one retrospective). The parameters analyzed were cross-sectional area, wrist-forearm index, entry-exit index, thinning range, palmar bowing of the flexor retinaculum, and vascularity/mobility. Current evidence allows us to affirm that ultrasound is useful in screening for CTS.

Analysis of the effects of different surgical approaches on corporotomy localization in inflatable penile implant surgery performed by expert implant surgeons.

Inflatable penile prostheses may be a solution for patients with erectile dysfunction. To our knowledge, no data exist regarding the effect of different surgical approaches used during implantation on the site of the corporotomy. The main purpose of this multicentre study was to investigate the influence of different surgical approaches on the corporotomy site.Data were collected from six expert implant surgeons. Surgical notes were searched for the incision site, proximal, distal and total corporal length measurement, total cylinder length, length of rear tip extenders, surgery time, type of implant, and reservoir placement. The association between the proximal/distal corporal length and the recorded covariates was examined using a linear mixed model.A total of 1757 patients who underwent virgin prosthesis implantation were included in the analysis. Analysis of proximal/distal measurements was performed on 1709 patients. The proximal/distal ratio had a mean of 0.8 ± 0.3 in penoscrotal incisions (n = 391), 0.7 ± 0.2 in infrapubic incisions (n = 832) and 0.7 ± 0.2 in subcoronal (n = 486) incisions. We observed no significant differences in proximal/distal measurements between the highest-volume surgeons.We could not draw a firm conclusion about the difference in corporotomy site between different surgical approaches, but we found no significant difference between the highest-volume surgeons using different techniques.

Estimation of the post-mortem interval of human skeletal remains using Raman spectroscopy and chemometrics.

An important demand exists in the field of forensic analysis to objectively determine the post-mortem interval (PMI) when human skeletal remains are discovered. It is widely known that bones undergo different chemical and physical processes after death, mainly due to their interaction with the environment in which they are found, although it is not known exactly what these processes consist of. Multiple techniques have been used so far to follow up these and other post-mortem changes and thus establish the time elapsed since the individual's death, but they present important drawbacks in terms of reliability and accuracy. The aim of this research was to propose an analytical methodology capable of determining the PMI by using non-destructive Raman spectroscopy measurements of human skeletal remains. The recorded Raman spectra provided valuable and potentially useful information from which a multivariate study was performed by means of orthogonal partial least squares regression (OPLSR) in order to correlate the PMI with the detected spectral modifications. A collection of 53 real human skeletal remains with known PMI (15 years ≤ PMI ≤ 87 years) was analysed and used for building and validating the OPLS model. The PMI of 10 out of 14 validation samples could be determined with an accuracy error of less than 30%, demonstrating the adequate predictive performance of the OPLS model even in spite of the large inter-individual variability it handled. This opens up the possibility of applying the OPLS model in combination with non-destructive techniques to the determination of the PMI of human skeletal remains that have been buried in conditions similar or equal to those of cemetery niches and in a geographic location with a Mediterranean climate, which is an important achievement for forensic medicine and anthropology.

Critically ill COVID-19 patients attended by anesthesiologists in northwestern Spain: a multicenter prospective observational study. / Pacientes críticos COVID-19 atendidos por anestesiólogos en el Noroeste de España: estudio multicéntrico, prospectivo, observacional.

BACKGROUND AND OBJECTIVES: There are limited information on outcome, complications and treatments of critically ill COVID-19 patients requiring admission to an intensive care unit (ICU). The aim of this study is to describe the clinical ICU course, treatments used, complications and outcomes, of critically ill COVID-19 patients admitted in seven ICU in Galicia region during the 2020 March-April pandemic peak. METHODS: Between March 21 and April 19, 2020, we evaluated critically ill COVID-19 patients admitted to the ICU of Anesthesia of seven hospitals in Galicia, northwestern Spain. Outcome, complications, and treatments were monitored until May 6, 2020, the final date of follow-up. RESULTS: A total of 97 critically ill COVID-19 patients were included. During ICU stay, mechanical ventilation became necessary in 80 (82.5%) patients, and tracheostomy in 22 (22.7%) patients. Prone position was used frequently in both intubated (67.5%) and awake (27.8%) patients. Medications consisted of antivirals agents (92.7%), corticosteroids (93.8%), tocilizumab (57.7%), and intermediate or high doses of anticoagulants (83.5%). The most frequent complications were ICU-acquired infection (52.6%), thrombosis events (16.5%), and reintubation (9.3%). After a median follow-up of 42 (34-45) days, 15 patients (15.5%) deceased, 73 patients (75.2%) had been discharged from ICU, and nine patients (9.3%) were still in the ICU. CONCLUSIONS: A high proportion of our critically ill COVID-19 patients required mechanical ventilation, prone positioning, antiviral medication, corticosteroids, and anticoagulants. ICU complications were frequent, mainly infections and thrombotic events. We had a relatively low mortality of 15,5%.

Facial Squamous Cell Carcinoma and Abdominal Peripheral Nerve Sheath Tumour with Rhabdomyoblastic Differentiation in a Rough-toothed Dolphin (Steno bredanensis).

We report the pathological features of a facial squamous cell carcinoma (SCC) and an abdominal peripheral nerve sheath tumour (PNST) with rhabdomyoblastic differentiation in an aged free-ranging rough-toothed dolphin (Steno bredanensis). The animal was found stranded dead in poor body condition. On external examination, there was a 25 × 7 × 3 cm extensively ulcerated area on the right maxillary region of the rostrum, involving the oral mucocutaneous junction with prominent nodular edges, severe soft tissue loss and extensive maxillary and premaxillary bone lysis. On abdominal dissection, a 5 × 4 × 3.5 cm pale tan to red, raised mass expanded the inner aspect of the right transverse abdominis muscle. Microscopically, the aggressive facial lesion was an acantholytic SCC with extensive osteolysis; there was no evidence of metastasis in the tissues examined. The abdominal mass had cytohistomorphological features compatible with a localized PNST, including whorling, Antoni A and Antoni B areas and Verocay bodies intermixed with rhabdomyoblastic components, as suggested by phosphotungstic acid haematoxylin stain. This neoplasm was locally infiltrative, yet no metastases were observed in the tissues examined. No immunohistochemical investigations could be performed due to lack of tissue availability. Total DNA from the formalin-fixed and paraffin wax-embedded SCC was extracted and tested by polymerase chain reaction for herpesvirus and papillomavirus genetic material. There was no amplification for either of these genera. Other pathological findings observed in this animal were related to the 'live-stranding stress response'. The severity and extent of the facial SCC likely related to anorexia and poor body condition and might have played a role in the stranding and death of this dolphin. These two tumour subtypes add to the relatively uncommon reports of neoplasia in cetaceans. Specifically, these appear to be the first neoplasia records for rough-toothed dolphins, including the first documentation of a PNST with features compatible with rhabdomyoblastic differentiation in a marine mammal.

Development of a loop-mediated isothermal amplification assay for specific detection of all known subspecies of Clavibacter michiganensis.

AIMS: Clavibacter michiganensis is an important bacterial plant pathogen that causes vast destruction to agriculturally important crops worldwide. Early detection is critical to evaluate disease progression and to implement efficient control measures to avoid serious epidemics. In this study, we developed a sensitive, specific and robust loop-mediated isothermal amplification (LAMP) assay for detection of all known subspecies of C. michiganensis. METHODS AND RESULTS: Whole genome comparative genomics approach was taken to identify a unique and conserved region within all known subspecies of C. michiganensis. Primer specificity was evaluated in silico and with 64 bacterial strains included in inclusivity and exclusivity panels; no false positives or false negatives were detected. Both the sensitivity and spiked assay of the developed LAMP assay was 1 fg of the pathogen DNA per reaction. A 100% accuracy was observed when tested with infected plant samples. CONCLUSIONS: The developed LAMP assay is simple, sensitive, robust and easy to perform using different detection platforms and chemistries. SIGNIFICANCE AND IMPACT OF THE STUDY: The developed LAMP assay can detect all known subspecies of C. michiganensis. The LAMP process can be performed isothermally at 65°C and results can be visually assessed, which makes this technology a promising tool for monitoring the disease progression and for accurate pathogen detection at point-of-care.

The Negro River (Ancash-Peru): A unique case of water pollution, three environmental scenarios and an unresolved issue.

This paper is focused on the hydrogeochemical characterization of the Negro River along its course, as well as in the proposal of a functioning model for the contamination processes in order to establish potential cause-effect relationships between water quality, geology (ARD), mining activities (AMD) and the tectonic framework as transmission vector of acidity, metals and sulphates. The scenario shows a heavily-contaminated river compared to the unaffected regional background. By graphical and statistical treatments of physico-chemical data of Negro River and the unaffected values of regional background and other AMD/ARD representative rivers' it is possible to conclude that Antamina Mine, is not the cause of the Negro River contamination, without the need of isotopic tracers, but just through the inexistent concentrations of Cu, Bi and Mo found in the waters. In the proposed contamination model, climatic factors (glacial retreat) activate geological (ARD) processes. The tectonic scenario (faults) intervenes as a transport medium of the contamination flux from the sulphide oxidation surface in upper altitudes until the spring in lower altitudes. At the end, it is concluded that this contamination comes from the recent glacial retreat in areas near the Cordillera Blanca that has left massive amounts of sulphide materials exposed to weathering conditions, oxidizing naturally (ARD processes) and finally contributing to the contamination of the Negro River through faults. In this case, we would face an ARD process in the strict sense, which is the direct oxidation of sulphides outcropping in the upper part of the mountain with the generation of sulphates, the release of hydrogen ions and the consequent generation of acid and the dissolution of the metals. This ARD process would come from the glacial retreat, which, through the faults, transports contaminated water until the spring.

Application of fuzzy logic tools for the biogeochemical characterisation of (un)contaminated waters from Aljustrel mining area (South Portugal).

Aljustrel mining area (South Portugal) belongs to the Iberian Pyrite Belt (IPB). It is classified of high environmental risk due to its large tailings and to the Acid Mine Drainage (AMD) affected waters, generated by sulphides' oxidation. Integrating biological parameters (for the first time) in the input data matrix of the software PreFuRGe, allowed a better discrimination of the diatoms' responses to the stimuli caused by the hydrochemical changes imposed by the processes affecting water quality. Each hydrochemical scenario, was modeled by imposing maximum and minimum limits for each antecedent, according to the conditions imposed by the consequent, which in this case were the number of diatom species and pH. Thus, PreFuRGe evidenced some qualitative aspects that could not be achieved by classic statistics. pH appeared as the main discriminator of diversity and diatom species composition, nevertheless and due to the complex environment under study other chemical interactions must be considered: (a) AMD waters, with extremely low pH values, but also with extremely high hydrogeochemical complexity, represented by a mixture of metals, do not allow to associate, unequivocally, the reduction in diatom diversity to pH, but also to high metal (loid)s concentrations; (b) in the most alkaline waters, with higher abundance of diatom species, average to high concentrations of Na and Cl (due to Cenozoic sediments) do not seem to affect diatom diversity. This methodology proved to be an efficient tool to establish, for the first time, cause-effect relationships, improving the comprehension between biological (diatoms) and hydrochemical parameters.

Esquizofrenia paranoide y peritación psiquiátrica forense. Presentación de un caso / Paranoid schizophrenia and forensic-psychiatric expert assessment. Case presentation

La Medicina Legal y la Psiquiatría son ciencias estrechamente relacionadas, y es habitual que los peritos médicos asesoren a los tribunales y jueces en materias de carácter psiquiátrico, para ayudar a esclarecer hechos delictivos. Establecer el estado mental de una persona que comete un delito, analizar de forma retrospectiva a qué nivel funcionaba el sujeto cuando lo cometió, y a su vez, establecer su facultad para comprender el alcance de su acción y dirigir su conducta en dicho momento, es una de las tareas más difíciles que se le presenta a la Psiquiatría Forense. En este artículo, se aborda de manera conjunta, por un equipo multidisciplinario, la presentación de un caso que se llevó a la comisión de peritación mental de la ciudad de Matanzas, en Cuba, ya que se acusaba a un joven con antecedentes de esquizofrenia paranoide del delito de homicidio en grado de tentativa, y era imperativo para el tribunal poder dilucidar si el sujeto en cuestión, en el momento de agredir a su víctima, conservaba o no la facultad para comprender el alcance de su acción y dirigir su conducta

Legal Medicine and Psychiatry are tightly related sciences, being usual that medical experts advise our courts and judges in the subjects of psychiatric character for helping in clarifying criminal acts. To establish the mental status of a person committing a criminal offence, to analyze retrospectively the level the subject functioned at when he committed it, and at the same time, to establish his faculty to understand the reach of his actions and to direct his behaviour at that moment, are the most difficult tasks that Forensic Psychiatry could afford. In this article, a multidiscipline team works in the presentation of a case that was taken to the mental assessment commission of Matanzas, Cuba, because a young man, with antecedents of paranoid schizophrenia, was accused in attempted murder, and it was imperative for the court to elucidate if, at the moment of assaulting his victim, the judged kept or not the faculty of understanding the reach of his action and directing his behavior

Síndrome de bazex: acroqueratosis paraneoplásica secundaria a cáncer de próstata / Bazex syndrome: paraneoplasic acroqueratosis secondary to prostatic cancer

La piel puede ofrecer el primer síntoma guía en el 1% de los pacientes con neoplasias internas. Las manifestaciones cutáneas de malignidades internas se pueden producir por invasión directa de la piel por el tumor y por diseminación metastásica, pero existen mecanismos indirectos que inducen la aparición de signos y síntomas cutáneos no relacionados con el tumor primitivo. El Síndrome de Bazex es una rara dermatosis descrita por Bazex y colaboradores en 1965. Se caracteriza por la presencia de placas eritematosas, psoriasiformes, que típicamente afectan a las manos, los pies, la nariz y los pabellones auriculares. La inexperiencia puede motivar retrasos en el diagnóstico, haciendo que la neoplasia asociada se encuentre en estadios avanzados en el momento del diagnóstico. Se discute un caso clínico de un paciente masculino de 53 años de edad, hipertenso, quien acude por presentar lesiones cutáneas tipo placas hipertróficas, hiperpigmentadas, descamativas y dolorosas con fondo eritematoso acompañados de secreción hialina amarillenta en regiones acrales y cuero cabelludo. La biopsia cutánea reportó granulocitosis y aumento del espesor de la capa córnea; en los cultivos bacteriano y micológico de tejido dérmico creció flora habitual. La biopsia prostática diagnosticó adenocarcinoma prostático Gleason 4/5, Se inició hormonoterapia y se realizó prostatectomía total, con mejoría clínica significativa posterior al inicio del tratamiento. La acroqueratosis de Bazex es un proceso muy infrecuente, con pocos casos descritos en la literatura. Su reconocimiento temprano podría permitir el diagnóstico de la neoplasia asociada en estadios más precoces y conducentes a un tratamiento más temprano(AU)

The skin can show the first symptom in 1% of patients with internal neoplasias. Cutaneous manifestations of internal malignancies can be caused by direct invasion of the skin by the tumor and by metastatic dissemination, but there are indirect mechanisms that induce the appearance of cutaneous signs and symptoms unrelated to the primitive tumor. Bazex Syndrome is a rare dermatosis described by Bazex et al. in 1965. It is characterized by the presence of erythematous, psoriasiform plaques, which typically affect the hands, feet, nose, and ear-lobes. The lack of experience may carry diagnostic delays and the associated neoplasia could be at advanced stages when diagnosed. We describe here the case of a 53-year-old male patient, who consulted for cutaneous lesions.These were hypertrophic, hyperpigmented, scaly and painful plaques with an erythematous background accompanied by a yellowish hyaline secretion in the hands, feet and scalp. A skin biopsy was done that reported granulocytosis and increased thickness of the corneal layer; in addition, bacterial and mycological culture of dermal tissue were negative. The prostate biopsy diagnosed a prostate adenocarcinoma, Gleason 4/5. Hormone therapy was started and total prostatectomy was performed, with significant clinical improvement .Bazex acroqueratosis is a very rare process, with few cases described in the literature. Its early recognition could allow the diagnosis of the associated neoplasia in earlier stages, leading to earlier treatment(AU)

Automatic CDR Estimation for Early Glaucoma Diagnosis.

Glaucoma is a degenerative disease that constitutes the second cause of blindness in developed countries. Although it cannot be cured, its progression can be prevented through early diagnosis. In this paper, we propose a new algorithm for automatic glaucoma diagnosis based on retinal colour images. We focus on capturing the inherent colour changes of optic disc (OD) and cup borders by computing several colour derivatives in CIE L∗a∗b∗ colour space with CIE94 colour distance. In addition, we consider spatial information retaining these colour derivatives and the original CIE L∗a∗b∗ values of the pixel and adding other characteristics such as its distance to the OD centre. The proposed strategy is robust due to a simple structure that does not need neither initial segmentation nor removal of the vascular tree or detection of vessel bends. The method has been extensively validated with two datasets (one public and one private), each one comprising 60 images of high variability of appearances. Achieved class-wise-averaged accuracy of 95.02% and 81.19% demonstrates that this automated approach could support physicians in the diagnosis of glaucoma in its early stage, and therefore, it could be seen as an opportunity for developing low-cost solutions for mass screening programs.

Rare earth elements mobility processes in an AMD-affected estuary: Huelva Estuary (SW Spain).

Huelva Estuary is a transition zone where REE-rich acidic waters interact with saline-alkaline seawater. This mixing process influences the geochemical and mineralogical characteristics of particulate and dissolved fractions. The Tinto River has >11,000µgL-1 dissolved REE (pH=1.66), whereas seawater only reaches 8.75·10-2µgL-1 dissolved REE (pH=7.87). REE-normalized patterns in "pH<6 solutions" are parallel and show similarities, diminishing their concentration as pH increases. Sequential extraction performed on the generated precipitates of mixed solutions indicates that most REE are associated to the residual phase. In a second order, REE are associated with soluble salts at pH3 and 3.5 whereas in sediments generated at pH4 and 5, they are distributed in salts (1° extraction), poorly crystallized Fe-bearing minerals (schwertmannite, 3° extraction) and well crystallized Fe-bearing minerals (goethite - hematite, 4° extraction). Finally, precipitated REE are highest at pH6 newly formed minerals with a release to solution in higher pH.

Geochemical behavior of an acid drainage system: the case of the Amarillo River, Famatina (La Rioja, Argentina).

The Amarillo River (Famatina range, Argentina, ~29° S and ~67° W) is unusual because acid mine drainage (AMD) is superimposed on the previously existing acid rock drainage (ARD) scenario, as a Holocene paleolake sedimentary sequence shows. In a markedly oxidizing environment, its water is currently ferrous and of the sulfate-magnesium type with high electrical conductivity (>10 mS cm-1 in uppermost catchments). At the time of sampling, the interaction of the mineralized zone with the remnants of mining labors determined an increase in some elements (e.g., Cu ~3 to ~45 mg L-1; As ~0.2 to ~0.5 mg L-1). Dissolved concentrations were controlled by pH, decreasing significantly by precipitation of neoformed minerals (jarosite and schwertmannite) and subsequent metal sorption (~700 mg kg-1 As, 320 mg kg-1 Zn). Dilution also played a significant role (i.e., by the mixing with circumneutral waters which reduces the dissolved concentration and also enhances mineral precipitation). Downstream, most metals exhibited a significant attenuation (As 100 %, Fe 100 %, Zn 99 %). PHREEQC-calculated saturation indices (SI) indicated that Fe-bearing minerals, especially schwertmannite, were supersaturated throughout the basin. All positive SI increased through the input of circumneutral water. PHREEQC inverse geochemical models showed throughout the upper and middle basin, that about 1.5 mmol L-1 of Fe-bearing minerals were precipitated. The modeling exercise of mixing different waters yielded results with a >99 % of correlation between observed and modeled data.

O - "não"- lugar do reflexo no modo causal de seleção pelas consequências de Skinner / The - "no"- place of the reflex in the causal mode selection by consequences of Skinner

Skinner em 1 981 propôs um modo causal geral para explicar o comportamento envolvendo doisprocessos básicos e complementares: variação e seleção. Algumas vezes o selecionismo é apresentadocomo um substituto do mecanicismo dentro e fora do âmbito comportamental. Contudo, há um ponto detensão nessa interpretação: o comportamento/condicionamento reflexo. Esse tipo de comportamento e deaprendizagem seria explicado através de leis compatíveis com o mecanicismo, as leis do reflexo, nãoenvolvendo variação e seleção. Em que medida, então, a seleção pelas consequências seria um modoexplicativo geral se nem mesmo seria aplicável a todos os casos de comportamento? Uma interpretaçãoalternativa é oferecida sobre a natureza e o alcance do selecionismo skinneriano(AU)

O - "não"- lugar do reflexo no modo causal de seleção pelas consequências de Skinner / The - "no"- place of the reflex in the causal mode selection by consequences of Skinner

Skinner em 1 981 propôs um modo causal geral para explicar o comportamento envolvendo dois processos básicos e complementares: variação e seleção. Algumas vezes o selecionismo é apresentado como um substituto do mecanicismo dentro e fora do âmbito comportamental. Contudo, há um ponto de tensão nessa interpretação: o comportamento/condicionamento reflexo. Esse tipo de comportamento e de aprendizagem seria explicado através de leis compatíveis com o mecanicismo, as leis do reflexo, não envolvendo variação e seleção. Em que medida, então, a seleção pelas consequências seria um modo explicativo geral se nem mesmo seria aplicável a todos os casos de comportamento? Uma interpretação alternativa é oferecida sobre a natureza e o alcance do selecionismo skinneriano

Assessment of metal contamination, bioavailability, toxicity and bioaccumulation in extreme metallic environments (Iberian Pyrite Belt) using Corbicula fluminea.

The Iberian Pyrite Belt (SW Iberian Peninsula) has intense mining activity. Currently, its fluvial networks receive extremely acid lixiviate residue discharges that are rich in sulphates and metals in solution (acid mine drainage, AMD) from abandoned mines. In the current study, the sediment and water quality were analysed in three different areas of the Odiel River to assess the risk associated with the metal content and its speciation and bioavailability. Furthermore, sediment contact bioassays were performed using the freshwater clam Corbicula fluminea to determine its adequacy as a biomonitoring tool in relation to theoretical risk indexes and regulatory thresholds. Reburial activity and mortality were used as the toxic responses of clams when exposed to contaminated sediment. The results showed coherence between the water and sediment chemical contamination for most of the metals. The reburial activity was correlated with the metal toxicity, but no clam mortality was registered. The bioaccumulation of the studied metals in the clam did not have a significant correlation with the bioavailable fraction of the metal content in the environment, which could be related to a potential different speciation in this singular environment. The bioaccumulation responses were negative for As, Cd and Zn in highly contaminated environments and were characterized as severe, considerable and low potential environmental risks, respectively. The results show that C. fluminea is a good biomonitor of Cu and Pb.