The Evolution of Function in the Rab family of Small GTPases

Dissertation presented to obtain the PhD degree in Computational Biology.

Development of a satellite based PM10 concentration product for urban areas

Dissertação para obtenção do Grau de Doutor em Engenharia do Ambiente

Molecular regulation of secondary gorwth: searching for SHORT-ROOT function in cork formation

The analysis of molecular regulators involved in controlling the maintenance and function of plant meristems has been the subject of many studies. Some master regulators of these processes have been identified in Arabidopsis benefiting from the array of tools available for genetic and molecular analysis in this model plant. However, aspects such as secondary growth that are more extensively observed in woody plants, have been less studied. Secondary growth is responsible for the enlargement of the plant stems and roots and results from the activity of the lateral (secondary) meristems, vascular cambium and cork cambium (phellogen), which produce two important renewable natural resources, wood and cork, respectively.(...)

Assembly and function of a protein cross-linking enzyme during bacterial spore morphogenesis

Sporulation in Bacillus subtilis culminates with the formation of a dormant endospore. The endospore (or spore) is one of the most resilient cell types known and can remain viable in the environment for extended periods of time. Contributing to the spore’s resistance and its ability to interact with and monitor its immediate environment is the coat, the outermost layer of B. subtilis spores. The coat is composed by over 70 different proteins, which are produced at different stages in sporulation and orderly assembled around the developing spore.(...)

Evaluation of uv spectrophotometry for estimation of nitrite and nitrate in nitrified urine

Water is a limited resource for which demand is growing. Contaminated water from inadequate wastewater treatment provides one of the greatest health challenges as it restricts development and increases poverty in emerging and developing countries. Therefore, the connection between wastewater and human health is linked to access to sanitation and to human waste disposal. Adequate sanitation is expected to create a barrier between disposed human excreta and sources of drinking water. Different approaches to wastewater management are required for different geographical regions and different stages of economic governance depending on the capacity to manage wastewater. Effective wastewater management can contribute to overcome the challenges of water scarcity. Separate collection of human urine at its source is one promising approach that strongly reduces the economic and load demands on wastewater treatment plants (WWTP). Treatment of source-separated urine appears as a sanitation system that is affordable, produces a valuable fertiliser, reduces pollution of water resources and promotes health. However, the technical realisation of urine separation still faces challenges. Biological hydrolysis of urea causes a strong increase of ammonia and pH. Under these conditions ammonia volatilises which can cause odour problems and significant nitrogen losses. The above problems can be avoided by urine stabilisation. Biological nitrification is a suitable process for stabilisation of urine. Urine is a highly concentrated nutrient solution which can lead to strong inhibition effects during bacterial nitrification. This can further lead to process instabilities. The major cause of instability is accumulation of the inhibitory intermediate compound nitrite, which could lead to process breakdown. Enhanced on-line nitrite monitoring can be applied in biological source-separated urine nitrification reactors as a sustainable and efficient way to improve the reactor performance, avoiding reactor failures and eventual loss of biological activity. Spectrophotometry appears as a promising candidate for the development and application of on-line nitrite monitoring. Spectroscopic methods together with chemometrics are presented in this work as a powerful tool for estimation of nitrite concentrations. Principal component regression (PCR) is applied for the estimation of nitrite concentrations using an immersible UV sensor and off-line spectra acquisition. The effect of particles and the effect of saturation, respectively, on the UV absorbance spectra are investigated. The analysis allows to conclude that (i) saturation has a substantial effect on nitrite estimation; (ii) particles appear to have less impact on nitrite estimation. In addition, improper mixing together with instabilities in the urine nitrification process appears to significantly reduce the performance of the estimation model.

Electromyography function, disability degree, and pain in leprosy patients undergoing neural mobilization treatment

INTRODUCTION: This study aimed to evaluate the effect of the neural mobilization technique on electromyography function, disability degree, and pain in patients with leprosy. METHODS: A sample of 56 individuals with leprosy was randomized into an experimental group, composed of 29 individuals undergoing treatment with neural mobilization, and a control group of 27 individuals who underwent conventional treatment. In both groups, the lesions in the lower limbs were treated. In the treatment with neural mobilization, the procedure used was mobilization of the lumbosacral roots and sciatic nerve biased to the peroneal nerve that innervates the anterior tibial muscle, which was evaluated in the electromyography. RESULTS: Analysis of the electromyography function showed a significant increase (p<0.05) in the experimental group in both the right (Δ%=22.1, p=0.013) and the left anterior tibial muscles (Δ%=27.7, p=0.009), compared with the control group pre- and post-test. Analysis of the strength both in the movement of horizontal extension (Δ%right=11.7, p=0.003/Δ%left=27.4, p=0.002) and in the movement of back flexion (Δ%right=31.1; p=0.000/Δ%left=34.7, p=0.000) showed a significant increase (p<0.05) in both the right and the left segments when comparing the experimental group pre- and post-test. The experimental group showed a significant reduction (p=0.000) in pain perception and disability degree when the pre- and post-test were compared and when compared with the control group in the post-test. CONCLUSIONS: Leprosy patients undergoing the technique of neural mobilization had an improvement in electromyography function and muscle strength, reducing disability degree and pain.

Mental health and the crisis: Evidence from share

Mental health constitutes a significant share of the global burden of disease. It is shaped to a great extent by socioeconomic factors and is vulnerable to external shocks. The recent financial crisis brought about stressors prone to trigger and aggravate mental illnesses. This project presents a micro analysis of the effect of the economic crisis on mental health in eleven European countries, through the estimation of individual health production functions accounting for socioeconomic controls and macroeconomic indicators. We find that mental health has deteriorated since 2007, even though the development of depression episodes is unchanged. Additionally, his variation can be partially attributed to economic recession and budgetary cuts in health spending.

Degree of disability, pain levels, muscle strength, and electromyographic function in patients with Hansen's disease with common peroneal nerve damage

INTRODUCTION: This study evaluated the degree of disability, pain levels, muscle strength, and electromyographic function (RMS) in individuals with leprosy. METHODS: We assessed 29 individuals with leprosy showing common peroneal nerve damage and grade 1 or 2 disability who were referred for physiotherapeutic treatment, as well as a control group of 19 healthy participants without leprosy. All subjects underwent analyses of degree of disability, electromyographic tests, voluntary muscle force, and the Visual Analog Pain Scale. RESULTS: McNemar's test found higher levels of grade 2 of disability (Δ = 75.9%; p = 0.0001) among individuals with leprosy. The Mann-Whitney test showed greater pain levels (Δ = 5.0; p = 0.0001) in patients with leprosy who had less extension strength in the right and left extensor hallucis longus muscles (Δ = 1.28, p = 0.0001; Δ = 1.55, p = 0.0001, respectively) and dorsiflexion of the right and left feet (Δ = 1.24, p = 0.0001; Δ = 1.45, p = 0.0001, respectively) than control subjects. The Kruskal-Wallis test showed that the RMS score for dorsiflexion of the right (Δ = 181.66 m·s-2, p = 0.001) and left (Δ = 102.57m·s-2, p = 0.002) feet was lower in patients with leprosy than in control subjects, but intragroup comparisons showed no difference. CONCLUSIONS: Leprosy had a negative influence on all of the study variables, indicating the need for immediate physiotherapeutic intervention in individuals with leprosy. This investigation opens perspectives for future studies that analyze leprosy treatment with physical therapeutic intervention.

Trust, alliance management capability and the alliance management function: A comparative analysis of Portuguese SMEs

Strategic alliances represent a key driver for internationalization and growth, being the purpose of this work project to better understand the intertwined relationship between trust and the existence of an alliance management position. Previous research supports the positive impact of such position in stock market returns. However, little attention has been given to the impact of such position on the level of trust in the collaborative arrangement, which is deemed to be a key driver for alliance success. A qualitative comparative case-study of three Portuguese SMEs is used to draw conclusions from the literature to real life business cases and it demonstrates the positive impact of an alliance management position on trust.

Is autonomic function associated with left ventricular systolic function in Chagas heart disease patients undergoing treatment for heart failure?

Introduction The association between cardiac autonomic and left ventricular (LV) dysfunction in Chagas disease (ChD) is controversial. Methods A standardized protocol that includes the Valsalva maneuver, a respiratory sinus arrhythmia (RSA) test, and an echocardiographic examination was used. Spearman correlation coefficients (rho) were used to investigate associations. Results The study population consisted of 118 ChD patients undergoing current medical treatment, with an average LV ejection fraction of 51.4±2.6%. The LV ejection fraction and diastolic dimension were correlated with the Valsalva index (rho=0.358, p<0.001 and rho=-0.266, p=0.004, respectively) and the RSA (rho=0.391, p<0.001 and rho=-0.311, p<0.001, respectively). Conclusions The impairment of LV function is directly associated with a reduction of cardiac autonomic modulation in ChD.

EDP - A new estimation algorithm

The aim of this work project is to analyze the current algorithm used by EDP to estimate their clients’ electrical energy consumptions, create a new algorithm and compare the advantages and disadvantages of both. This new algorithm is different from the current one as it incorporates some effects from temperature variations. The results of the comparison show that this new algorithm with temperature variables performed better than the same algorithm without temperature variables, although there is still potential for further improvements of the current algorithm, if the prediction model is estimated using a sample of daily data, which is the case of the current EDP algorithm.

Liver synthesis function in chronic asymptomatic or oligosymptomatic alcoholics: correlation with other liver tests

Liver function and its correlation with bilirubin and hepatic enzymes were evaluated in 30 male chronic asymptomatic or oligosymptomatic alcoholics admitted into the psychiatric hospital for detoxification and treatment of alcoholism. Hypoalbuminemia, lowered prothrombin activity, hypotransferrinemia and hypofibrinogenemia were detected in 32 %, 32 %, 28 %, and 24 % of patients, respectively. Transferrin was elevated in 8 %. Greater prevalence of hyperbilirubinemia was found in patients with lowered prothrombin activity, hypofibrinogenemia, or hypotransferrinemia. No correlation was found between serum bilirubin or aminotransferase levels and normal or elevated albumin levels, time or activity of prothrombin, and fibrinogen levels. Serum alkaline phosphatase was elevated in normoalbuminemics and gamma-glutamyltransferase in patients with lowered prothrombin activity. Hypoalbuminemia was associated with hypofibrinogenemia, hypotransferrinemia with elevated aspartate aminotransferase or gamma-glutamyltransferase, and hypertransferrinemia with elevation of alanine aminotransferase. These data indicated the occurrence of hepatic dysfunction due to liver damage caused directly by alcohol or by alcoholism-associated nutritional deficiencies.

The importance of the ligation of the inferior thyroid artery in parathyroid function after subtotal thyroidectomy

We prospectively studied the effects of the ligation of the inferior thyroid artery (ITA) on postoperative hypoparathyroidism in 48 patients who underwent functional subtotal thyroidectomy. Patients were randomized into two groups: A, with bilateral ligation of the ITA and B, without ligation of the ITA. Parathyroid function was checked preoperatively and after surgery by clinical examination and measurement of total calcium, intact PTH, urinary calcium, and AMPc. RESULTS: A significant incidence of postoperative hypocalcemia occurred: 17% in group A and 13% in B on the 4th postoperative day. Six months later, the incidence was 5% in Group A and 0% in Group B. These differences were not statistically significant between the two groups, and neither were any of the other clinical and laboratory observations. CONCLUSION: The ligation of the ITA was not an important causal factor for the occurrence of postoperative hypocalcemia after subtotal thyroidectomy.

Kidney function after left renal vein ligation in the dog

The ligature of the left renal vein is an alternative whenever this vessel is injured. The purpose of this study was to evaluate the capacity of the affluents of the left renal vein, proximal to the ligature, to maintain tissue vitality and function of the left kidney. Fifteen mongrel male dogs were divided in 3 groups of 5 dogs: Group I (control) - a laparotomy was performed, and the abdominal structures were only identified; Group II - the left renal vein was tied, close to vena cava; Group III - the same procedure as for Group II and a right nephrectomy. Blood urea nitrogen and serum creatinine levels were measured before the procedure, and every 3 days during 4 weeks in the postoperative period. Renal arteriography and an excretory urogram were performed on the animals that survived 60 days. Thereafter, or immediately after precocious death, the kidneys were removed for histological examination. All the animals of Group III died before two months (mean = 10.5 +-3.2 days), while the animals of Group II survived during that period. There was a complete exclusion of the left kidney in all dogs that underwent renal vein ligature. In the animals of Group II, the renal cortico-medullary limits could not be identified. At microscopy, the aspect was suggestive of nephrosclerosis. In the animals of Group III, the left kidney was enlarged, and a great amount of intravascular and intrapelvic blood clots were observed. At microscopy, extensive areas of necrosis, inflammatory infiltration, and hemorrhage were identified. In conclusion, the tributaries of the renal vein were not sufficient to maintain the tissue vitality and function of the left kidney after ligature of its main vein.

On the function of the floccular complex of the vertebrate cerebellum: implications in paleoneuroanatomy

The cerebellum floccular complex lobes (FCLs) are housed in the FCL fossa of the periotic complex. There is experimental evidence indicating that the FCLs integrate visual and vestibular information, responsible for the vestibulo-ocular reflex, vestibulo-collic reflex, smooth pursuit and gaze holding. Thus, the behavior of extinct animals has been correlated with FCLs dimension in multiple paleoneuroanatomy studies. Here I analyzed braincase endocasts of a representative sample of Mammalia (48 species) and Aves (59 species) rendered using tomography and image segmentation and tested statistical correlations between the floccular complex volume, ecological and behavioral traits to assess various previously formulated paleobiological speculations. My results demonstrate: 1) there is no significant correlation between relative FCL volume and body mass; 2) there is no significant correlation between relative FCL and optic lobes size in birds; 3) average relative FCL size is larger in diurnal than in nocturnal birds but there is no statistically significant difference in mammals; 4) feeding strategies are related with different FCL size patterns in birds, but not in mammals; 5) locomotion type is not related with relative FCL size in mammals; 6) agility is not significantly correlated with FCL size in mammals. I conclude that, despite the apparent relation between FCL size and ecology in birds, the cerebellum of tetrapods is a highly plastic structure and may be adapted to control different functions across different taxonomic levels. For example, the european mole (Talpa europaea) which is fossorial and practically blind, has a FCL fossae relative size larger than those of bats, which are highly maneuverable. Therefore, variation in FCL size may be better explained by a combination of multiple factors with relation to anatomical and phylogenetic evolutionary constraints.