Large-scale instabilities in a STOVL upwash fountain

The fountain flow created by two underexpanded axisymmetric, turbulent jets impinging on a ground plane was studied through the use of laser-based experimental techniques. Velocity and turbulence data were acquired in the jet and fountain flow regions using laser doppler velocimetry and particle image velocimetry. Profiles of mean and rms velocities along the jet centreline are presented for nozzle pressure ratios of two, three and four. The unsteady nature of the fountain flow was examined and the presence of large-scale coherent structures identified. A spectral analysis of the fountain flow data was performed using the Welch method. The results have relevance to ongoing studies of the fountain flow using large eddy simulation techniques

Business model of non-governamental organizations for the development of the education sector in Mozambique: A construtivist approach

This research aims to determine the business model of non-governmental development organizations (NGDOs) of the education sector in Mozambique. The work adopts a constructivist methodological approach in two stages: (i) inductive, centered on the construction of a proposal of social business model Canvas from the observation of 15 NGDOs operating in the education sector in the country, based on a theoretical framework solidly supported in the literature; (ii) deductive, testing the proposed model using a panel technique that allowed the refinement and reconstruction of the proposal initially formulated. The paper contributes to the literature on social business models by making a pioneering validation of knowledge built in this area and in a field of application not yet explored. The contribution to international relations lies at the level of the data collected and information produced on international cooperation in Mozambique.info:eu-repo/semantics/publishedVersio

A family of E. coli expression vectors for laboratory scale and high throughput soluble protein production

BACKGROUND: In the past few years, both automated and manual high-throughput protein expression and purification has become an accessible means to rapidly screen and produce soluble proteins for structural and functional studies. However, many of the commercial vectors encoding different solubility tags require different cloning and purification steps for each vector, considerably slowing down expression screening. We have developed a set of E. coli expression vectors with different solubility tags that allow for parallel cloning from a single PCR product and can be purified using the same protocol. RESULTS: The set of E. coli expression vectors, encode for either a hexa-histidine tag or the three most commonly used solubility tags (GST, MBP, NusA) and all with an N-terminal hexa-histidine sequence. The result is two-fold: the His-tag facilitates purification by immobilised metal affinity chromatography, whilst the fusion domains act primarily as solubility aids during expression, in addition to providing an optional purification step. We have also incorporated a TEV recognition sequence following the solubility tag domain, which allows for highly specific cleavage (using TEV protease) of the fusion protein to yield native protein. These vectors are also designed for ligation-independent cloning and they possess a high-level expressing T7 promoter, which is suitable for auto-induction. To validate our vector system, we have cloned four different genes and also one gene into all four vectors and used small-scale expression and purification techniques. We demonstrate that the vectors are capable of high levels of expression and that efficient screening of new proteins can be readily achieved at the laboratory level. CONCLUSION: The result is a set of four rationally designed vectors, which can be used for streamlined cloning, expression and purification of target proteins in the laboratory and have the potential for being adaptable to a high-throughput screening

Thermal restraint and fire resistance of columns

A proposal is made, based on the results of a series of tests and calculations, with the aim of being used as a simple method to correct the value of the critical temperature of steel columns free to elongate, in order to take into account the restraint effect of the structure to which they belong in a practical situation. To better illustrate the possible types of behaviour of heated steel columns with elastic restraint to the thermal elongation, and the reasons why the critical temperature of axially loaded slender steel columns with thermal restraint can sometimes be lower than the critical temperature of the same columns free to elongate, a simple model is presented and used in a qualitative analysis.http://www.sciencedirect.com/science/article/B6V37-46WW50B-1/1/139a30367738460772843d1279c4c32

Semen Cryopreservation in Brazilian Freshwater Fish: Advances and Main Challenges

Studies on semen cryopreservation in Brazilian freshwater fish have been growing in number of publications and investigated species. Despite this apparent increase in research, standardization of cryoprotocols is still missing, making it clear that the grounds on the quality of cryopreserved semen has not yet reached a level that guarantee satisfactory results for its replication. This chapter aims to make a critical and reflective analysis on the ways cryopreservation of freshwater fish semen has been conducted in Brazil. The difficulties in standardizing protocols, broodstock, and selection of genetically superior animals; the barriers in transferring technology from laboratory benches to the field and make feasible the use of cryopreserved semen on a commercial scale; the formation of germplasm banks and the responsible use of cryopreserved material are also discussed. We have no intention to point out the successes and mistakes that may have been committed in pursuing development of cryopreservation protocols, but a reflection on the future directions considering what should be pondered on this subject with objectivity and scientific consolidation

The complexity of porphyrin-like pigments in a marine annelid sheds new light on haem metabolism in aquatic invertebrates

PTDC/MAR-BIO/0113/2014. UID/Multi/04378/2019. UID/QUI/50006/2019. SFRH/BD/120030/2016. SFRH/BD/109462/2015. IF/00265/2015.True green pigments in the animal kingdom are scarce and are almost invariably porphyrinoids. Endogenous porphyrins resulting from the breakdown of haem are usually known as “bile pigments”. The pigmentation of intertidal Polychaeta has long gained attention due to its variety and vivid patterning that often seems incompatible with camouflage, as it occurs with Eulalia viridis, one of the few truly green Polychaeta. The present study combined UV and bright-field microscopy with HPLC to address the presence and distribution of pigments in several organs. The results showed two major types of porphyrin-like pigments, yellowish and greenish in colour, that are chiefly stored as intraplasmatic granules. Whereas the proboscis holds yellow pigments, the skin harbours both types in highly specialised cells. In their turn, oocytes and intestine have mostly green pigments. Despite some inter-individual variation, the pigments tend to be stable after prolonged storage at −20 °C, which has important implications for future studies. The results show that, in a foraging predator of the intertidal where melanins are circumscribed to lining the nervous system, porphyrinoid pigments have a key role in protection against UV light, in sensing and even as chemical defence against foulants and predators, which represents a remarkable adaptive feature.publishersversionpublishe

Different kidney function trajectory patterns before dialysis in elderly patients: clinical implications and outcomes

Background. Identifying trajectories of kidney disease progression in chronic kidney disease (CKD) patients may help to deliver better care. We aimed to identify and characterize trajectories of renal function decline in CKD patients and to investigate their association with mortality after dialysis.Methods. This retrospective cohort study included 378 CKD patients who initiated dialysis (aged 65 years and over) between 2009 and 2016. Were considered mixed models using linear quadratic and cubic models to define the trajectories, and we used probabilistic clustering procedures. Patient characteristics and care practices at and before dialysis were examined by multivariable multinomial logistic regression. The association of these trajectories with mortality after dialysis was examined using Cox models.Results. Four distinct groups of eGFR trajectories decline before dialysis were identified: slower decline (18.3%), gradual decline (18.3%), early rapid decline (41.2%), and rapid decline (22.2%). Patients with rapid eGFR decline were more likely to have diabetes, more cognitive impairment, to have been hospitalized before dialysis, and were less likely to have received pre-dialysis care compared to the patients with a slower decline. They had a higher risk of death within the first and fourth year after dialysis initiation, and after being more than 4 years in dialysis.Conclusions. There are different patterns of eGFR trajectories before dialysis initiation in the elderly, that may help to identify those who are more likely to experience an accelerated decline in kidney function, with impact on pre ESKD care and in the mortality risk after dialysis

Familial pseudoxanthoma elasticum with nephrocalcinosis: a case report

Pseudoxanthoma elasticum (PXE) is an autosomal recessive genetic disorder characterized by progressive calcification and fragmentation of elastic fibres. PXE commonly involves the reticular dermis, the Bruch membrane of the eye, and blood vessels. PXE is caused by mutations in the ABCC6 gene. More than 300 pathogenic ABCC6 mutations are known. Two of these mutations are common: p.R1141X in exon 24, with a prevalence of 30%, and the Alu–mediated deletion of exons 23 to 29 (EX23_29del; p.A999_S1403del) found in 10-20% of patients. Homozygosity is rare. A 40-year-old female with a previous diagnosis of PXE was admitted in Nephrology Outpatient Clinic for nephrocalcinosis. She has two sisters, one of which also has a diagnosis of PXE and nephrocalcinosis. Physical examination revealed the presence of typical skin and ocular abnormalities. Microscopic and gross hematuria was reported in both affected sisters. Abdominal ultrasound confirmed bilateral cortico-medullar nephrocalcinosis. Calcium and phosphorus levels in blood and urine were normal. Hyperparathyroidism, renal tubular acidosis, hypervitaminosis D and hyperoxaluria were excluded. Renal biopsy showed only minor glomerular abnormalities. Medullary sponge kidney was identified by excretory urography. Genomic DNA was used as a template for PCR amplification of the region spanning introns 22 to 29 of ABCC6 [Pfendner et al., J Med Genet 2007;44:621-8]. The oligonucleotide cocktail used generated a 552bp PCR product for the normal sequence, and a 652bp product for the deletion mutation. Both sisters with PXE were homozygous for the EX23_29del mutation. The third sister did not carry this deletion. There are occasional reports of diffuse visceral calcifications (testis, mammary gland) in PXE. PXE-associated nephrocalcinosis was previously noted in four patients belonging to different families. This is the first report of familiar co-occurrence of PXE and nephrocalcinosis with medullary sponge kidney. These sisters’ peculiar phenotype could be due to their unusual genotype, or other shared genetic and environmental factors

Primeiro transplante renal ABO-incompatível realizado em Portuga

Kidney transplantation is the optimal treatment of end-stage renal disease (ESRD) improving survival and quality of life for most recipients. In our country, potential living donors have been refused due to the ABO incompatibility barrier. However, ABO -incompatible living donor kidney transplant is presently common practice in several countries with good outcomes. The authors describe a case of a 49-year-old female patient, with chronic kidney disease due to autosomal dominant polycystic kidney disease, who had started haemodialysis 10 months before and with blood group O. The living donor was a 53-year-old sister with blood group B. The desensitization protocol was based on rituximab and plasmapheresis. The induction protocol used was basiliximab, tacrolimus, mofetil mycophenolate and metilprednisolone. Five days post -transplant she presented a normal graft function that remained during the eight months follow -up. This case reveals the first ABO incompatible living donor kidney transplant performed in Portugal with excellent outcomeO transplante renal é a modalidade de tratamento da doença renal crónica estadio 5 associada a melhores sobrevivência e qualidade de vida. No nosso país muitos potenciais dadores vivos têm sido recusados devido à incompatibilidade ABO. Contudo, o transplante renal de dador vivo ABO incompatível é hoje prática comum em diversos países com resultados positivos. Os autores descrevem o caso de doente do sexo feminino, de 49 anos, com doença renal crónica secundária a doença renal poliquística autossómica dominante, que havia iniciado hemodiálise 10 meses antes e com grupo sanguíneo O. O dador vivo foi uma irmã de 53 anos, grupo sanguíneo B. O protocolo de dessensibilização baseou -se em rituximab e plasmaferese. O protocolo de indução foi com basiliximab, tacrolimus, micofenolato de mofetil e metilprednisolona. Evoluiu com função normal do enxerto 5 dias pós-transplante que se manteve durante o follow-up de 8 meses. Este caso clínico ilustra o primeiro transplante renal de dador vivo ABO incompatível efectuado em Portugal com excelente resultad

Malignancy after renal transplantation: a single-centre experience

Introduction: Malignancy management in renal transplant recipients is becoming a major factor affecting long‑term patient survival. Thus, we intended to evaluate both incidence and prognosis of malignant diseases following renal transplantation at a single centre in Portugal. Methods: We studied retrospectively the 2,358 patients who underwent kidney transplantation (KT) between 1983 and 2014. Apart from descriptive analysis, both demographic and clinical characteristics of cancer and non‑cancer cancer patients were compared. Results: During a median follow‑up of 118 (IQR 57‑179) months, 139 patients (5.8%) developed 158 de novo malignancies, with a median time from KT to diagnosis of 76..5 (IQR 21.0‑132.0) months. When compared to non‑cancer patients, they were older at KT date, had longer graft survival and a lower living donor recipients’ prevalence. As for post-transplant malignancies analysis, the most common were non‑cutaneous non‑lymphomatous cancers (49.4%, n=78), skin cancers (35.4%, n=56) and post‑transplant lymphoproliferative disorders (9.5%, n=15). Considering specific diagnosis, squamous cell carcinoma and basal cell carcinoma with 17.1% and 16.5% respectively, and non‑Hodgkin lymphomas with 7.6%, were the most frequent. Global mortality among cancer patients was 36.0%, with a median time of 9.7 (IQR 1.9‑17.5) months from time of diagnosis to death. As for survival analysis, cancer patient survival was significantly lower while censored graft survival was significantly higher in this group. Conclusion: Incidence and characteristics of malignancy following renal transplantation in our unit are similar to those globally described, despite some traits probably a result of specific ethnic and environmental characteristics.info:eu-repo/semantics/publishedVersio