156 research outputs found
O outplacement : caracterização e novas tendências
Mestrado em Gestão de Recursos HumanosO outplacement é uma técnica de gestão de recursos humanos que tem como intuito auxiliar o colaborador em transição na carreira a ultrapassar o trauma do despedimento e a encontrar uma nova colocação. O presente estudo tem como objectivo caracterizar o outplacement, descrever as suas novas tendências, e também comparar as suas práticas entre Portugal e o Reino Unido através de estudos de caso. Optou-se pela pesquisa qualitativa, devido ao seu carácter descritivo e exploratório. Os resultados evidenciam semelhanças e diferenças no que concerne as práticas do outplacement nos dois paÃses. A composição dos programas de outplacement e uso de indicadores para a medição da sua eficácia, a abordagem directa ao cliente enquanto estratégia de marketing, a complexidade do perfil do consultor de outplacement e a relação de proximidade que se estabelece entre o mesmo e o candidato, bem como o incentivo a comunicação contÃnua, são práticas de outplacement comuns a Portugal e ao Reino Unido. Foi ainda possÃvel constatar que as principais diferenças entre os dois paÃses se relacionam com a duração dos programas, uso exclusivo da tecnologia, existência de um mercado mais competitivo no Reino Unido e consequente maior necessidade de diferenciação por parte das empresas britânicas. Por fim, concluiu-se que o principal desafio que as empresas de outplacement enfrentam nos dias de hoje consiste na necessidade de educar o mercado acerca do real valor desta prática, articulada à s vantagens da consultoria one-to-one.Outplacement is a human resource management practice which intends to assist employees in career transition to overcome the trauma of redundancy and find a new job. The present study aims to characterize outplacement, describe it?s new trends, and compare it?s practices between Portugal and the United Kingdom. Given the lack of in-depth knowledge on this subject in Portugal, it was resorted to qualitative research, due to its descriptive and exploratory nature. The method of investigation chosen was conducting case studies, related to companies analyzed in both countries. The results show similarities and differences concerning outplacement practices in both countries. The composition of outplacement programs and use of indicators to measure its effectiveness, the direct approach to customers as a marketing strategy, the outplacement consultant profile complexity and the close relationship established between consultant and candidate as well as encouraging continuous communication are common outplacement practices in Portugal and the United Kingdom. It was further established that the main differences between the two countries relate to program duration, exclusive use of the technology, the existence of a competitive market in the UK and consequently a greater need for differentiation by British companies. Finally, it is concluded that the main challenges that outplacement companies face nowadays is the need of educating the market about the real value of this practice, articulated to the benefits of one-to-one consulting
Reabilitação sustentável de edifÃcios de habitação
Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade
Nova de Lisboa para obtenção do grau de Mestre em Engenharia Civil – perfil de ConstruçãoO parque habitacional edificado é no momento actual um dos elementos que contribui
grandemente para a degradação do ambiente.
O nÃvel de eficiência dos edifÃcios de habitação, no que respeita ao consumo de
recursos naturais e ao conforto ambiental, leva a que hoje se possa considerar que o mesmo parque construÃdo é insustentável.
Deste modo, importa que se conheçam e determinem os problemas concretos do
parque habitacional edificado de modo a se poder contribuir para a resolução desta situação.
Conhecidos os principais problemas dos edifÃcios de habitação, bem como as suas
causas, compreende-se que para a sua resolução existe a necessidade de adaptar o processo de reabilitação tradicional ao conceito de construção sustentável, a qual pode ser conseguida com base nos sistemas de avaliação e certificação da sustentabilidade na construção.
A presente dissertação pretende então contribuir para que o processo de reabilitação de edifÃcios seja realizado de forma sustentável, com base na problemática referida
A simple method for detection of phosgene based on the infiltration of a colorimetric probe in nanostructure TiO2 films
A new sensor for detection of phosgene has been developed by incorporating an indicator to nanocrystalline TiO2 thin films.Nanocrystalline films were used to detect phosgene by measuring the variation of their absorbance spectra. In presence of phosgene, a new band at ~450 nm appears in the spectrum. The response intensity (absorbance at 450 nm) has been found to be concentration-dependent.Currently we are working in the detection limits and others parameters of his sensor.Motivation: The motivation in this work is because it had been a very lethal gas in World War II and is currently being used in numerous production processes as frequent as the manufacture of pesticides, dyes or herbicides. It is for this reason that an early detection is required since the lethality of said gas is very high.Methods: The method used is screen printing. In this method a reagent has been deposited in a nanocrystalline film which is then impregnated with the reagent solution and subsequently exposed to the analyte.Results: The results obtained are very satisfactory. The tolerance limit for humans is very significantly lowered.Conclusions: To the best of our knowledge, the sensor described, is one of the best optical and solid sensors in phosgene´s detection, reaching concentrations below the parts per million
Study of the stability and persistence of commercial perfumes under different thermal and UV-Vis light conditions.
Motivation: Nowadays, the perfume industries need to be more and more competitive due to the broad offer existing in the market; For this reason they try to create quality products with optimisted compositions in order to reduce the fabrication costs.In particular, the persistence of the fragrance and stability of the color are the main challanges in the quality of perfumes fabricated by Saphir Laboratories .In this work, we have studied these two propierties in several perfums from this company, stored under diferent agresive conditions of light and temperature. These experiments have been done with different proportions of protective additives in order to optimized the current formulae.Methods: The chemical stability against external factors such as UV light and temperature in terms of the quality and behavior of the samples was study for several perfumes provided by the company (Saphir Laboratories). For these experiencies we have used a UV-Vis lamp( (LOT-Oriel) and a Cary 100 UV-VIs spectrophotometer (Agilent). Additionally, the study of the temperature was carried out by introducing the samples in a lab oven for different periods of time at different temperatures. Different proportions in the perfume composition (Natural essence,water, ethanol,antioxidant BHT,colorants and the UV filters Neosorb and Uvasorb) were used in the above experiments. Finally, the long lasting of the different perfums was analyzed by both human tasting and an electronic nose equipment (SACMI Imola).Results and conclusions: Each perfume has a different behavior,maintaining its identity from 4 to 15 hours exposed to UV depending on the perfum. Regarding the temperature, it can be concluded that at temperatures above 50 ° C the chemical stability of the sample is lost. Additionally, these conditions and even lower temperatures (40ºC) lead to an oxidation of the essential oils, producing rancidity of the essence, which is summarized in more intense olfactory notes with respect to the original perfumes
Influence of light and temperature on the stability of commercial perfumes
Motivation: The industrial sector of perfumes lives many moments of fierce competition among related companies. Survival in this world requires of make technological advances in order to develop products that eliminate unwanted effects, include novelty, and satisfy the customer.The way to achieve this is to do research in order to achieve added value with respect to competitors, such as image, color and design; persistence and anti-aging by oxidation of perfumes due to solar or thermal exposure.In our case, we have perfumes from Saphir Laboratories that present problems with degradation by color, oxidation by redox processes, and low persistence. Whereby, we need to look for optimization ways in order to improve the elaboration recipe at a reduced cost.Methods: Methods used are UV-Vis spectrophotometry using a cary 100 ( Agilent) as colorimeter for colour photodegradation and photoxidation of perfums irradiated with a LOT-Oriel UV-vis lamp. For the persistence studies we compare results of human tastings by non-expert people and measures of intensity by changes in resistance (conductimetric) in a electronic nose powered by an electronic olfactory system software.Results: We have studied four perfumes with color photodegradation problems with promising results. We have found the best proportion of the additives used in their composition . On the other hand, the electronic nose measurements indicate an increase of intensity of odor for samples strored at high temperatures (40ºC) that has been confirmed by human tasting tests . This behaviour has been attributed to a maceration process in pefumes after thermal treatment, simulating our warm climate, given that temperature conditions do not reach 50ºC at which a phase separation takes place.Conclusions: The studies carried out have confirmed that the essential oils of perfumes are the main cause of the loss in the effectiveness of the added UV filters, producing a photodegradation of its own color; we have also achieved favorable results in possible modifications in the proportions of additives to improve the stability. On the other hand, the measures resulting from the electonic nose indicate that thermal treatment of a reconstructed perfume with the addition of ambroxane as fixative reduce the loss of volatile compounds resulting in a greater signal to that of the commercial perfume without ambroxane
Pseudomonas aeruginosa-Candida albicans polymicrobial biofilms in ventilator-associated infections (VAP): evaluating the post-antimicrobial effect of amphotericin B/polymyxin B combined activity
Introduction: Mixed bacterial-fungal colonization of the endotracheal tubes is now evident, with
microbial interplay withstanding common antimicrobial therapy and paying for persistent and severe
VAP infections. While alternative therapeutic strategies effectively targeting inter-kingdom biofilms are
required, the role of each microorganism need to be appraised to deliver effective treatments.
Hypothesis and aims: We earlier reported the combination therapy involving polymyxin B (PMB) and
amphotericin B (AMB) as holding an attractive therapeutic option to treat dual-species biofilms. This
study aimed to determine the post-antimicrobial phenomenon of PMB/AMB combined action in P.
aeruginosa (PA) +Candida albicans (CA) biofilms, and to ascertain the events underlying biofilm growth
restoration.
Methodology: Post-antimicrobial effect of PMB combined with AMB was assessed in 24-h dual-species
biofilms. Cell culturability and viability were evaluated by CFU and Live/Dead staining, respectively. The
gene expression profile was assessed by qPCR.
Results: Results showed that PA+CA biofilms lost their culturability straightaway being exposed to
PMB/AMB combined solution. However, 24h was enough to both species recover their growth onto agar
medium, with microbial counts approximating those observed for pre-treated biofilms. Following the
subsequent treatment cycle, CFU estimation was only slightly disturbed. L/D results revealed that PA
and CA populations displayed a compromised status at the end of the first PMB/AMB treatment cycle.
Finishing the 24-h-regrowth cycle, most biofilm-encased species exhibited viability, which endured after
the second treatment period. Transcriptional analysis of dual-species biofilms exposed to PMB/AMB
combined action showed a high expression level in all PA resistance-encoded genes anrB, galU, mexA
and algD and in ERG3 and ALS2 CA genes.
Conclusion: Our finsings showed that PA+CA biofilms were able to escape to the combined action of
PMB/AMB, and both species had a preeminent role while retaining adaptive resistance mechanisms that
likely contributed for their recovery and adaptation on the ensuing treatments.info:eu-repo/semantics/publishedVersio
Glutathione detection using a fluorescence prove based on porphyrin-Hg complex
Glutathione (GSH) is an abundant tripeptide found in the almost all cells. GSH is relevant as antioxidant and in regulation of some carcinogenic mechanims. It's well known that disturbances in GSH homeostasis could unleash a cancer disease. Therefore, its necessary GSH effective proves to prevent future physiological alterations due to a decrease or increase of the tripectide concentrations. Herein, we report a turn-on fluorecence sensor based on a highly fluoresncence porphyrin derivated (chlorin) complexed with Hg (II).Methods: To study the formation of Hg(II)-Chlorine complex, a different concentrations of a mercury cloride (II) solution was added to a fixed concentration of chlorine and fitting to the Stern-Volmer ecuation. To study the response to glutathione, a certain ratio of Hg(II):Chlorine was exposed to increasing amounts of GSH. To determain the limit of detection (LOD), a quarter of the maximun slope of the curve is calculated for each sample.Results: Chlorine coordinates adequately to mercury producing a quenching according to the Stern-Volmer equation. For the determination of glutathione in water, a pH of 7.4 (physiological pH) was maintained and increasing amounts of glutathione were introduced for a fixed ratio of mercury-chlorine complex. At increasing amounts of glutathione, it is coordinated with mercury and releasing chlorine, resulting in an increase in fluorescence due to free chlorine. The response curve is sigmoidal in shape as glutathione first complexes with free mercury, and once this is depleted, GSH captures the mercury complexed to chlorine, producing the increase in fluorescence mentioned above.This experiment was repeated for different mercury:chlorine ratios (2:1, 5:1 and 10:1) with the 2:1 ratio having a lower detection limit of 0.01 uM. It is now intended to transfer this system to a titanium dioxide based film
ZIF-8 MOF used as optic sensor for toxic gases
Metal-Organic frameworks (MOFs) are crystalline organic-inorganic porous materials comprised of metal atoms or clusters coordinated by organic ligands. ZIF-8 (zeolitic imidazole framework), due to the abscense of an intricsic fluorescenc, has never been used as optical sensor. In this works, ZIF-8 has been dopped with Cd (II) atoms (2.5%), showing an huge enhacement of the fluorescent compared with the non-dopped ZIF-8. This new material is suitable for optical sensing, being sensitive to hydrogen sulfice gas, which causes quenching of the luminescence proportionally to its concentration.Methods: ZIF-8 was synthesized at room temperature mixing a methanol solution of Zn(NO3)2·6H2O with a methanol solution of 2-methyllimidazole (Hmim), with Zn (II), Hmim, methanol ratio of 1:8:700 [1].ZIF-8 was dopped with Cadmium by four different methods; the dopped samples was named ZIF-8-A1, ZIF-8-B, ZIF-8-A2 and ZIF-8-B2. The methodology followed was described by H. Fei et al. in [2], with some modifications. The difference among the varieties was the solvent and the post-treatment after mixing the compounds.The dopping method was accomplished by dissolving 0.4 mmol of Cd(NO3)2 and 20mg of ZIF-8 in DMF (3mL) (for ZIF-8-B and ZIF-8-B2) or methanol (3mL) (for ZIF-8-A2). ZIF-8-B was obtained by gentenly heating at 60ºC for 48h; ZIF-8-A2 was obtained by stirring for 48 at room temperature; ZIF-8-B2 was obtained by stirring for 48h at room temperature.For sensing measurements, the samples was exposured to saturated gases of H2S and the fluorescence changed was monitored
Enhancement of the intrinsic fluorescence of ZIF-8 via post-synthetic cation exchange with Cd2+ and its incorporation into PDMS films for selective sulfide optical sensing
In this study, ZIF-8 MOF nanocrystals were synthesized and post-synthetically modified by applying different cation exchange strategies. Addition of cadmium nitrate in either methanol or DMF followed by either magnetic stirring or gentle heating led to the incorporation of a small amount of Cd (II) ions into the crystal structure in most cases, as clearly demonstrated by several characterization techniques including PXRD, SEM-EDS and FT-IR. This novel doped material exhibits a high fluorescence with the maximum emission wavelength at 444 nm upon excitation at 380 nm, which allows its use as an effective optical sensor. The sensing capability of the Cd-doped ZIF-8 material was demonstrated by its exposure to sulfide ions in aqueous solution. The fluorescence of the doped material was gradually quenched as the concentration of S2− was increased. Sensing devices based on mixed-matrix membranes (MMMs) were fabricated by using poly (dimethyl siloxane) (PDMS) as a hosting matrix for the Cd-doped ZIF-8 crystals, giving rise to fluorescent sensing films with fast and selective responses against a broad number of potential interferents
Insights into Pseudomonas aeruginosa and Candida albicans consortia challenged by antimicrobials
Ventilator associated pneumonia (VAP), an usual nosocomial infection in
the intensive care units and the most common in mechanically ventilated
patients, is a serious problem due to high mortality and morbidity rates
associated. The presence of the endotracheal tube is the principal risk
factor for developing VAP because its surface is prone to microbial
adhesion and the formation of biofilms, deserving thus high attention in
clinical settings. Cell-to-cell communication is an important mechanism of
interaction between VAP microorganisms, being involved in the process
known as quorum-sensing (QS) that regulate the expression of virulence.
To evaluate bacteria fungi cross-talk in co-infection, the biofilm-forming
ability of Pseudomonas aeruginosa and Candida albicans, individually or
jointly, before and after antibiotic and antifungal co-treatment was tested.
Biofilms were characterized in terms of total mass and cell viability.
Results showed that no antimicrobial combination was successful in the
binary biofilms eradication. In some cases, the tolerance of the
polymicrobial consortia was higher than that of single biofilms,
highlighting that P. aeruginosa and C. albicans established synergistic
relationships. To gain knowledge helping to explain those interactions, a
quantitative real-time PCR approach was followed to inspect the
expression profiles of some cell-cell communication genes involved in
biofilm resistance. To overcome the tolerance issues, new antimicrobial
combinatorial approaches using QS-inhibitors are being tested. Some
combinations involving chlorogenic acid and ciprofloxacin displayed
promising anti-biofilm potential
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