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Cânhamo Industrial: Cultivo, Produção e Valorização de Coprodutos
Publication . Saragoça, Andreia de Fátima Pires; Cordeiro, Ana Isabel; Póvoa, Orlanda Viamonte
O presente trabalho foca-se no estudo do cânhamo industrial (Cannabis sativa L.), uma
cultura de elevada versatilidade, sustentabilidade e interesse económico. Nesta cultura
destaca-se o seu valor agronómico, ambiental e industrial, bem como a sua adaptação a
diversas condições edafoclimáticas. O estudo teve como objetivo principal avaliar o
comportamento agronómico de diferentes variedades em Elvas, incluindo parâmetros
como desenvolvimento fenológico, produtividade, germinação, teor de THC e potencial
fitotóxico. Os ensaios de germinação revelaram elevadas taxas de germinação em todas
as variedades, variando entre 75,0% e 94,0%, sendo apenas observada uma redução
significativa na variedade Santhica 27 entre os dois anos de avaliação. Os ensaios de
profundidade de sementeira demonstraram que a profundidade de 3 cm proporcionou
as melhores condições para a emergência e desenvolvimento inicial das plântulas. A
análise dos teores de canabinóides por cromatografia líquida de alta eficiência (HPLC)
demonstrou que todas as variedades apresentaram teores de THC inferiores ao limite
legal de 0,2%, variando entre valores residuais (<0,01%) e 0,10%. A variedade Futura 75
apresentou o maior teor de THC (0,03%), enquanto a Mona 16 registou o valor mais
elevado (0,10%). Os ensaios de fitotoxicidade demonstraram que os diferentes extratos
de cânhamo não afetaram significativamente a percentagem de germinação das sementes
de alface, que variou entre 82,0% e 92,5%. Contudo, observaram-se efeitos significativos
ao nível do crescimento radicular, particularmente nos extratos obtidos por decocção
e em concentrações mais elevadas, evidenciando a presença de compostos com
potencial alelopático. O comportamento agronómico do cânhamo industrial foi
fortemente influenciado pelas condições edafoclimáticas e pelas práticas culturais,
nomeadamente a data de sementeira, confirmando a importância do fotoperíodo e dos
fatores ambientais na regulação do desenvolvimento e produtividade da cultura. Este
estudo reforça o potencial do cânhamo industrial como cultura sustentável e
multifuncional nas condições do Alentejo.
Influence of non-financial rewards on multiple commitments in the Portuguese Armed Forces
Publication . Martins, Mónica Solange de Jesus Pereira Martins; Nascimento, José Luís
Faced with recruitment difficulties and the continuous outflow of personnel from their
ranks, military institutions are challenged to develop human resources policies that enhance
motivation and personnel retention.
This study analysed the influence of Non-Financial Rewards (NFR) on the multiple
commitments of Portuguese Armed Forces personnel – specifically commitment to the
supervisor, the military profession, and the organization – while considering the mediating role
of organizational trust. The objective is to provide evidence that allows the Armed Forces to
adjust their human resources policies in alignment with their strategic goals.
To this end, an electronic questionnaire was administered to 24,058 personnel from the three
branches of the Armed Forces, resulting in a final sample of 545 valid responses (a response
rate of approximately 2.27%).
The results confirm that NFR positively influence the different types of commitment, especially
in their affective dimension, and that this influence is partially mediated by organizational trust.
The tested structural model showed good fit indices and statistical stability; the calculative
dimension of commitment was eliminated due to its weak statistical explanation and theoretical
inadequacy within the military context.
Desafios da comunicação na era da Inteligência Artificial (IA)
Publication . Leandro, Alexandra; Campos Sobreira, Rosa Maria; Ferreira, Gil
Integrated micro-computed tomography and computational fluid dynamics analysis of stepwise enlargement in mesial root canals of mandibular molars
Publication . Furtado, Sofia Moura; Martins, Jorge N. R.; Silva, Emmanuel João Nogueira Leal; Pereira, Mário Rito; Versiani, Marco Aurélio; Ginjeira, António
Introduction: To evaluate how stepwise enlargement in the mesial root canals of mandibular first molars affect shaping outcomes and irrigant dynamics.
Methods: The shaping ability and irrigant flow patterns in mesial canals of mandibular first molars enlarged with ProTaper Next instruments (25/.06v, 30/.07v, 40/.06v) were evaluated using micro-computed tomography (micro-CT) and computational fluid dynamics (CFD). Instrument design and metallurgical properties were assessed by 3D scanning, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and differential scanning calorimetry to ensure manufacturing consistency. An extracted mandibular molar with two curved mesial root canals was selected and scanned by micro-CT to generate 3D models for CFD simulation. Root canals were prepared stepwise with the ProTaper Next. Digital canal and needle geometries were reconstructed from micro-CT and scanning electron microscopy data. CFD simulations were conducted in ANSYS Fluent to calculate irrigant velocity, wall shear stress, and apical pressure. For shaping analysis, ten mesial canals from 5 mandibular molars were scanned before and after each preparation step. Canal volume, surface area, unprepared surfaces, and pericervical dentine thickness were quantified. Data were analyzed using repeated measures ANOVA with Bonferroni correction (P < .05).
Results: Excluding for dimensions, all instruments shared similar metallurgical features and design characteristics, with minor surface imperfections. The open-ended needle consistently delivered irrigant to the working length, unlike the side-vented needle. Enlargement slightly increased apical velocity and irrigant density, particularly with the open-ended needle, which also generated higher wall shear stress and apical pressure. Canal volume and surface area increased significantly with larger files (P < .05), while unprepared areas decreased. Progressive canal enlargement significantly reduced minimal dentine thickness at the distal aspect of the mesial canals (most at 1–2 mm below the furcation), dropping from preoperative means of ∼1 mm to 0.60 mm after the 40/.06v instrument (P < .05), with the proportion of sections with dentine <0.5 mm increasing from 0% to 26%, while those >1 mm decreased markedly.
Conclusions: Progressive apical enlargement improved shaping and irrigant dynamics, but additional increases offered limited benefits. Irrigant effectiveness was more influenced by needle design than by size alone, suggesting that optimizing delivery systems may enhance cleaning efficiency while minimizing unnecessary dentine removal.
Impact of Sarcopenia on prognosis, treatment toxicity and surgical complications in locally advanced gastric cancer
Publication . Dias, David da Silva; Luz, Paulo; Fortuna, Ana; Águas, Ana; Machado, Mafalda; Gosálbez, Beatriz; Farate, Rosa; Pinho, Rita Clemente; Valente, Ana Carmo; Mendes, José Leão; Seladas, Marta Maria; Trabulo, Carolina; Ravasco, Paula
Background: Weight loss and skeletal muscle wasting are frequent in cancer and may influence treatment tolerance and outcomes. Computed tomography (CT) based body composition analysis at the third lumbar vertebra (L3) is an accurate method to quantify skeletal muscle in routine oncology care.
Methods: We performed a multicenter retrospective cohort study including 202 adults with locally advanced (stage IB–III) gastric cancer treated in four Portuguese hospitals (January 2020–December 2022). Skeletal muscle area (SMA) was assessed on baseline CT at the L3 vertebral level, using Data Analysis Facilitation Suite (DAFS) software v3.11.2, and skeletal muscle index (SMI) was subsequently calculated. Patients with low muscle quantity were classified as sarcopenic (below sex-specific SMI mean). We evaluated associations with relapse-free survival (RFS), overall survival (OS), FLOT chemotherapy dose-limiting toxicities (DLTs), and postoperative complications after gastrectomy.
Results: Mean age was 69 years, 65% had ECOG PS 0, 53% received FLOT chemotherapy protocol. Mean SMI was 49.6 cm2/m2 in males and 40.9 cm2/m2 in females and correlated positively, though moderately, with BMI (p < 0.01; r = 0.424). Sarcopenia was not significantly associated with RFS (p = 0.186) or OS (p = 0.168) at 30-month follow-up. Although numerical differences were observed (64% vs. 56% of patients did not relapse and 74% vs. 63% were alive, for non-sarcopenic vs. sarcopenic patients). Sarcopenia was associated with a higher risk of DLTs (p = 0.021; OR 2.56, 95% CI 1.15–5.73) and postoperative complications (p = 0.024; OR 2.16, 95% CI 1.11–4.21).
Conclusions: Sarcopenia significantly increases the risk of chemotherapy toxicity and postoperative complications in locally advanced gastric cancer. However, its effect on OS and RFS was not statistically significant at 30-month follow-up. Standardization of CT-based sarcopenia cut-offs remains a major barrier to clinical implementation.