Physiological responses of two tropical weeds to shade: I. Growth and biomass allocation Respostas fisiológicas de duas plantas invasoras tropicais ao sombreamento: I. Crescimento e alocação de biomassa

Ipomoea asarifolia (Desr.) Roem. & Schultz (Convolvulaceae) and Stachytarpheta cayennensis (Rich) Vahl. (Verbenaceae), two weeds found in pastures and crop areas in Brazilian Amazonia, were grown in controlled environment cabinets under high (800-1000 µmol m-² s-¹) and low (200-350 µmol m-² s-¹) light regimes during a 40-day period. For both species leaf dry mass and leaf area per total plant dry mass, and leaf area per leaf dry mass were higher for low-light plants, whereas root mass per total plant dry mass was higher for high-light plants. High-light S. cayennensis allocated significantly more biomass to reproductive tissue than low-light plants, suggesting a probably lower ability of this species to maintain itself under shaded conditions. Relative growth rate (RGR) in I. asarifolia was initially higher for high-light grown plants and after 20 days started decreasing, becoming similar to low-light plants at the last two harvests (at 30 and 40 days). In S. cayennensis, RGR was also higher for high-light plants; however, this trend was not significant at the first and last harvest dates (10 and 40 days). These results are discussed in relation to their ecological and weed management implications.<br>Ipomoea asarifolia (Desr.) Roem. & Schultz (Convolvulaceae) e Stachytarpheta cayennensis (Rich) Vahl. (Verbenaceae), duas plantas invasoras encontradas em pastagens e áreas agrícolas da Amazônia brasileira, foram cultivadas durante 40 dias, em câmaras de crescimento sob alto (800-1000 µmol m-² s-¹, "sol") e baixo (200-350 µmol m-² s-¹, "sombra") regime de luz. Em ambas as espécies a razão de massa e de área foliar por unidade de massa total da planta, e a área foliar por unidade de massa foliar foram maiores na sombra, enquanto a proporção de biomassa alocada para as raízes foi maior nas plantas ao sol. Em S. cayennensis a alocação de biomassa para tecido reprodutivo foi maior nas plantas ao sol, sugerindo uma provável menor habilidade dessa espécie de se manter sob condições de sombreamento. A taxa de crescimento relativo (TCR) em I. asarifolia foi, inicialmente, maior nas plantas ao sol, e após 20 dias passou a decrescer, tornando-se semelhante entre tratamentos nas últimas duas avaliações (aos 30 e 40 dias). Em S. cayennensis, a TCR foi também maior em plantas ao sol, porém esta tendência não foi significativa na primeira e última avaliação (10 e 40 dias). Esses resultados são discutidos com relação às suas importâncias ecológica e de manejo

Review of family-based approaches to improve postoperative outcomes among bariatric surgery patients

Bariatric surgery must be partnered with postoperative lifestyle modifications for enduring weight loss and related health effects to be fully appreciated. Little is known about how these lifestyle modifications may be affected by the involvement of other family members living in the household; therefore, this review describes current family-based approaches to improving postoperative outcomes in bariatric surgery patients and their families. A MEDLINE search of publications from 1999 to 2014 was conducted in January 2014. Retrieved titles and abstracts were assessed by 2 authors to determine relevance to the topic surrounding family-based approaches to improve postbariatric surgery outcomes. All study designs except case studies were considered if they included some aspect of family as a predictor in relation to improved health outcomes after surgery. Initial searches yielded 650 publications (bariatric surgery+family, n = 193; bariatric surgery+child, n = 338; bariatric surgery+spouse, n = 4; bariatric surgery+social support, n = 115). Two studies met criteria for a family-based approach to improving metabolic outcomes in bariatric patients. Seven studies discussed the impact of bariatric surgery on families. All other studies were excluded for not discussing family-based approaches. Despite limited documentation of family-based approaches on improving health outcomes in patients who underwent bariatric surgery, evidence suggests that such an approach may be advantageous if planned a priori to occur before, during, and after bariatric surgery. Future studies could test the combination of bariatric surgery and a family-based approach for improved metabolic outcomes in both the patient and involved family member(s)