Assessing multi slot versus single slot pool-type fishways suitability for potamodromous cyprinids: An experimental approach using numerical modelling and fish

Developing new fishway designs that provide suitable hydrodynamic conditions for multiple native freshwater fish species is paramount to mitigate the negative effects of anthropogenic barriers in rivers. This poses an increased challenge in Mediterranean regions, where water availability is limited and issue of conflicting demands. Vertical slot fishways (VSF) are considered one of the best types of technical fishways for potamodromous fish species. However, they generally require a greater amount of water to operate relatively to other type of facilities. The present study used 3D numerical modelling to compare the hydrodynamics and assess the hydraulic suitability for multiple fish species, of a widely used VSF and of two multi slot fishway (MSF) configurations. The MSF configuration requires a lower discharge to operate (\u3e 20% less discharge) than the VSF, while keeping similar flow depths. With the reduction in discharge, the velocity, turbulent kinetic energy and Reynolds shear stress values for MSF are also much lower than the values for VSF (c. 20 – 40% less). Hence, besides requiring smaller discharges than similar VSF design, the MSF seems to be less selective for fish species, particularly smaller-sized individuals, and individuals with weaker swimming capacities. Passage performance of the Iberian barbel, Luciobarbus bocagei (Steindachner, 1864) was subsequently assessed when negotiating a VSF and a MSF in an indoor full scale experimental model. Results showed that the Iberian barbel performed a significantly higher number of movements in the MSF when compared to the VSF. On the other hand, no differences were found in the entrance time, entry efficiency and overall fish performance between configurations. This study shows that numerical modelling complemented with laboratory fish experiments can be an important tool to develop cost-effective fishways

Session D7: Is CFD an Efficient Tool ao Develop Pool Type Fishways?

Abstract: Rivers longitudinal connectivity is compromised by man-made obstacles, such as dams and weirs, which affect fish movements, leading to populations decrease and genetic deterioration. Properly designed fishways re-establish connectivity, allowing for fish migration. The aim of our work is to contribute to a more fast and efficient development of pool-type fishways using hydrodynamic modelling, based on fish behaviour experiments. Modelling free surface flows in hydraulic structures with complex geometry, like pooltype fishways, with aerated and complex flow patterns, represents a significant research challenge. Knowledge already acquired in an experimental full scale indoor pool-type fishway in previous studies is used. A 1:2.5 scaled fishway of this facility was built and used to characterize velocity and turbulence in a pool-type fishway with cross-walls equipped with bottom orifices. An offset orifice configuration was used with consecutive orifices positioned on opposite sides of the cross-walls, creating a sinusoidal flow path. The measurements of velocity fields were made using Particle Image Velocimetry (PIV) and Acoustic Doppler Velocimetry (ADV). Velocity maps were obtained at several positions, for planes parallel to the bottom and parallel to the sidewalls. Parameters that influence fishways efficiency like velocity fields, turbulent kinetic energy and Reynolds shear stresses were determined. A 3D computational fluid dynamics (CFD) model of the fishway was developed using a commercial software FLOW-3D. Velocity fields, turbulent kinetic energy and Reynolds shear stresses were compared with the ones determined from PIV measurements and ADV measurements and results deviations between experimental and numerical data were analyzed. The use of FLOW 3D to simulate mean velocity patterns and flow turbulence in pooltype fishways and its use as design tool for new fishway geometries are discussed

Assessment of oil contamination in the bay of Porto Grande (Cape Verde) using the mullet Chelon bispinosus

Polycyclic aromatic hydrocarbons (PAHs) are a group of persistent organic pollutants, some of which are mutagenic and carcinogenic so PAH concentrations in fish used for human consumption are crucial to assess impact to human health. Total PAH concentrations in muscle and liver of mullets Chelon bispinosus from the Bay of Porto Grande (Cape Verde) (four sites in the bay and a control) ranged from 112.7 to 779.5 and 291.5 to 7548.7 ng/g d. w., respectively. Two and three ring PAHs were the most frequent (72.8 to 90.8% in the muscle and 75.9 to 98.3% in the liver), but levels of carcinogenic PAHs (mainly Dibenzo (a,h) antracene) in certain sites (CN and PG) are of concern. Results reflect a chronic PAH pollution in the bay and sources are a mixture of anthropogenic (petrogenic and pyrolytic) and natural sources, making their identification extremely complex. Although, BaP levels were below the threshold established by Cape Verde and the European Union, BaPEs levels in muscle ranged from 0.28 to 3.66 ng/g w. w. and BAPEs and TPAHs exposure for the average adult was 0.02 to 0.26 and 1.6 to 11.2 μg/day, respectively. Further knowledge of PAH concentrations in other species are necessary for a proper environmental risk assessment policy.Key words: Bay of Porto Grande, Cape Verde, Chelon bispinosus, mullets, PAHs, BaPEs, daily intake

Management of Iatrogenic Urorectal Fistulae in Men with Pelvic Cancer

INTRODUCTION: Urorectal fistula (URF) is a devastating complication of pelvic cancer treatments and a surgical challenge for the reconstructive surgeon. We report a series of male patients with URF resulting from pelvic cancer treatments, specifically prostate (PCa), bladder (BCa), and rectal cancer (RCa), and explore the differences and impact on outcomes between purely surgical and non-surgical treatment modalities. METHODS: Between October 2008 and June 2015, 15 male patients, aged 59-78 years (mean 67), with URF induced by pelvic cancer treatments were identified in our institutions. Patients with a history of diverticulitis, inflammatory bowel disease, or other benign conditions were excluded. We reviewed the patients' medical records for symptoms, diagnostic tests performed, type and etiology of the fistula, type of surgical reconstruction, followup, and outcomes. RESULTS: Fourteen patients underwent surgical reconstruction. One patient developed metastatic disease before URF repair and, therefore, was excluded from this study. Mean followup (FU) was 32.7 months (14-79). All patients received diverting colostomy and temporary urinary diversion. An exclusively transperineal approach was used in nine (64.3%) patients and a combined abdominoperineal in five (35.7%). Overall successful URF closure was achieved in 12 (85.7%) patients, nine (64.3%) of whom at the first reconstructive attempt, two (14.3%) after two attempts (in our institution), and one (7.1%) after three attempts (two of which elsewhere). An interposition flap was used in seven (50%) patients. Surgical reconstruction failed ultimately in two (14.3%) patients who still have a colostomy and do not wish any further reconstruction. CONCLUSIONS: Our study has several limitations, including its retrospective nature and the heterogeneity of our small patient cohort. Nonetheless, although surgical reconstruction of URF may be extremely difficult and complex in the non-surgical/energy ablation patients, its successful reconstruction is possible in most through a transperineal, or a more aggressive abdominoperineal, approach with tissue interposition in selected patients.info:eu-repo/semantics/publishedVersio

Different hydrogen-bonded chains in the crystal structures of three alkyl N-[(E )-1-(2-benzylidene-1-methylhydrazinyl)-3- hydroxy-1-oxopropan-2-yl]carbamates

Peer reviewedPublisher PD

Estudo preliminar aos níveis de eliminação em ovinos das raças merina branca e merina preta por estrongilídeos gastrointestinais .

As raças Merina Branca e Merina Preta apresentam um potencial de produção de carne assinalável, aliado a características de rusticidade, longevidade e resistência a doenças. Animais explorados em regimes extensivos, muitas vezes associados ao ecossistema montado, poderão ter um papel importante no âmbito dos novos modos de produção sustentada (Programa de conservação / Melhoramento Genético, 2007). As estrongiloses nos ovinos são responsáveis por importantes perdas económicas ao nível dos sistemas de produção. Estas perdas reflectem as alterações dos índices produtivos e reprodutivos, assim como no bem-estar e saúde animal. No controlo das estrongiloses gastrointestinais é necessário uma abordagem integrada que contribua para uma produção animal sustentável. Foi objectivo avaliar os níveis de eliminação de ovos/g de EGI (OPG) em ovinos das raças Merina Branca e Merina Preta e determinar a abundancia proporcional média dos diferentes géneros presentes. Procedeu-se à colheita de amostras coprológicas individuais directamente da ampola rectal a 40 fêmeas jovens e a 40 fêmeas adultas. Foram determinados os níveis de eliminação de OPG através da técnica modificada de Mackmaster (Hammond & Sewel, 1978). A abundancia proporcional média foi calculada após estudo morfométrico das L3 obtidas em coprocultura. No tratamento dos dados recorreu-se à análise de variância e análise descritiva. Nos níveis de eliminação de OPG verificaram-se diferenças significativas entre raças. Nas fêmeas jovens os valores obtidos revelaram uma diferença altamente significativa (p <0,01) entre as raças. Nas fêmeas adultas as diferenças verificadas foram apenas significativas (p <0,05). Após obtenção das L3 em coprocultura, foram identificados 3 géneros de EGI: Trichostrongylus sp.; Teledorsagia sp. e Oesophagostomum sp.. Na determinação da abundancia proporcional média dos géneros presentes, observou-se que a Teledorsagia sp. foi o género mais abundante nas fêmeas jovens enquanto que, Trichostriongylus sp. revelou-se como o mais abundante nas fêmeas adultas. Os resultados obtidos parecem expressar uma diferente capacidade de resistência à infecção por EGI nas duas raças. Sendo a resistência aos EGI um processo multifactorial, deverão ter-se em consideração factores não abordados neste estudo

Parasitofauna de Hoplias malabaricus Bloch, 1794 (Erythrinidae) do Estado do Amapá, Amazônia oriental, Norte do Brasil.

ENBRAPOA