Evaluation of novel beta-lactam antibiotics in comparison to cefotaxime on plant regeneration of <Emphasis Type="Italic">Citrus sinensis</Emphasis> L. Osb.

Identification of beta-lactam antibiotics that have negligible effects on plant regeneration is a critical step towards the establishment of a reliable Agrobacterium-mediated transformation protocol for perennial trees. In the present report, we have evaluated the effects of the novel beta-lactam antibiotics meropenem and timentin on plant regeneration of a perennial woody fruit plant, Citrus sinensis, in comparison with the commonly used beta-lactam cefotaxime. It was observed that, in contrast to cefotaxime, meropenem and timentin had a positive or no detrimental effect on the shoot regeneration from epicotyl explants. Residual effects of the beta-lactams from shoot regeneration medium also affected the subsequent ability of the roots to elongate. The addition of meropenem and/or timentin in the rooting medium mostly improved or did not affect the rooting ability of the adventitious shoots. These data indicated that meropenem and timentin can positively replace cefotaxime in Agrobacterium-mediated transformation of C. sinensis.     

Short‐Term Responses of Birds to Forest Gaps and Understory: An Assessment of Reduced‐Impact Logging in a Lowland Amazon Forest1

We studied physiognomy‐specific (i.e., gaps vs. understory) responses of birds to low harvest (18.7 m³/ha), reduced‐impact logging by comparing 3500 mist net captures in control and cut blocks of an Amazonian terra firme forest in Brazil at 20–42 mo postharvest. Species richness did not differ significantly between control (92 species) and cut (85) forest based on rarefaction to 1200 captures. Fifty‐six percent of all species were shared between control and cut forest, compared to the 64 percent shared between control blocks. Higher captures of nectarivores and frugivores in cut forest likely occurred as a consequence of postharvest resource blooms. Higher captures of some insectivores in cut as compared to control forest were unexpected, attributable to increased wandering or shifts from association with midstory to understory as a consequence of habitat alteration. Logging influenced capture rates for 21 species, either consistently, or via positive interaction with physiognomy or time (13 species higher in cut forest and 8 species higher in control forest). Cut understory sites had lower diversity (H′) and scaled dominance than understory and gap sites in control forest. Temporal changes in captures may have resulted from successional dynamics in cut forest: two guilds and three species increased in abundance. Increases in abundances of guilds and particular species were more prevalent in control than in cut forest, suggesting that logging displaced birds to control forest. In general, the effects of logging were relatively minor; low harvest rates and reduced‐impact methods may help to retain aspects of avian biodiversity in Amazon forest understories.     

Physiological Aspects of Melon (Cucumis melo L.) as a Function of Salinity

Journal of Plant Growth Regulation - This study evaluated the effect of saline water irrigation (4.5 dS m−1) on growth, gas exchange and mineral nutrient content in eight melon accessions and...     

Trypanocidal activity of a new pterocarpan and other secondary metabolites of plants from Northeastern Brazil flora

Two hundred fifteen compounds isolated from plants of Northeastern Brazil flora have been assayed against epimastigote forms of Trypanosoma cruzi, using the tetrazolium salt MTT as an alternative method. Eight compounds belonging to four different species: Harpalyce brasiliana (Fabaceae), Acnistus arborescens and Physalis angulata (Solanaceae), and Cordia globosa (Boraginaceae) showed significant activity. Among them, a novel and a known pterocarpan, a chalcone, four withasteroids, and a meroterpene benzoquinone were the represented chemical classes.     

Work ability of health care shift workers: What matters?

This paper aims at identifying variables associated with inadequate work ability among nursing personnel at a public hospital, considering factors related to socio-demographic, lifestyles, working conditions, and health outcomes. A cross-sectional study was conducted in a university hospital in S?o Paulo, Brazil, as part of a larger research study on tolerance to 12 h night work. Nursing staff included registered nurses, nurse technicians, and nurse aides; in total, there were 996 healthcare workers (878 female; 118 male) at the time of the study. Some 696 workers (69.9%) of the population agreed to participate. Data collection (October 2004-July 2005) was based on a comprehensive questionnaire about living and working conditions (including incivility at work, work demands, work control, and support), mental and physical health symptoms (fatigue and sleep problems), and work ability. This report presents analyses of the adapted Brazilian version of the Work Ability Index (WAI) and associated variables. The study population worked one of the following shift schedules at this hospital: 12 h nights followed by 36 h off or 9 h or 6 h day (morning or afternoon) shifts. The mean age of the respondents was 34.9 (S.D.+/-10.4) years of age; 31.5% of the participants held two jobs. Statistical analyses using a hierarchical multiple logistic regression model were performed to evaluate the factors associated with inadequate (moderate and low scores) of the WAI. The significantly associated factors were socio-demographic (income responsibility, sole breadwinner, raising kids, age group), working conditions (thermal discomfort, organization of the workplace, and verbal abuse), and health outcomes (high body mass index, obesity, sleep problems, and fatigue). In spite of limitations of the study design, results indicate that the nursing profession is associated with stressful working conditions, contributing to inadequate WAI. This is in addition to bad living conditions and precarious work. Intervention measures, either at the workplace or at individual levels, are necessary to prevent a decrease in work ability, even in this quite young working population.     

TP53 codon 72 polymorphism and type 2 diabetes: a case–control study in South Indian population

Molecular Biology Reports - TP53 functions primarily as a tumor suppressor, controlling a myriad of signalling pathways that prevent a cell from undergoing malignant transformation. This tumor...     

Punish and Voice: Punishment Enhances Cooperation when Combined with Norm-Signalling

Material punishment has been suggested to play a key role in sustaining human cooperation. Experimental findings, however, show that inflicting mere material costs does not always increase cooperation and may even have detrimental effects. Indeed, ethnographic evidence suggests that the most typical punishing strategies in human ecologies (e.g., gossip, derision, blame and criticism) naturally combine normative information with material punishment. Using laboratory experiments with humans, we show that the interaction of norm communication and material punishment leads to higher and more stable cooperation at a lower cost for the group than when used separately. In this work, we argue and provide experimental evidence that successful human cooperation is the outcome of the interaction between instrumental decision-making and the norm psychology humans are provided with. Norm psychology is a cognitive machinery to detect and reason upon norms that is characterized by a salience mechanism devoted to track how much a norm is prominent within a group. We test our hypothesis both in the laboratory and with an agent-based model. The agent-based model incorporates fundamental aspects of norm psychology absent from previous work. The combination of these methods allows us to provide an explanation for the proximate mechanisms behind the observed cooperative behaviour. The consistency between the two sources of data supports our hypothesis that cooperation is a product of norm psychology solicited by norm-signalling and coercive devices.     

Improvement in the bleaching of kraft pulp with xylanase from Penicillium crustosum FP 11 isolated from the Atlantic forest

Xylanase produced from the newly isolated Penicillium crustosum FP 11 and its potential in the prebleaching of kraft pulp were evaluated using a statistical approach. A Plackett–Burman design (PBD) was carried out to select the significant variables of the medium, these being NaNO₃, KH₂PO₄, MgSO₄, KCl, Fe₂(SO₄)₃, yeast extract, corn stover, and initial pH, in a liquid culture under static conditions for 6 d at 28?°C. Statistical analysis with a central composite design and response surface methodology showed that 0.15% (w/v) KH₂PO₄, 2% (w/v) corn stover, and an initial pH of 6.0 provided the best conditions for xylanase production. Furthermore, xylanase from P. crustosum FP 11 was effective in the bleaching of Eucalyptus kraft pulp, with a significant kappa efficiency of 35.04%. Therefore, the newly isolated P. crustosum FP 11 from the Atlantic Forest biome in Brazil showed two advantages: xylanase production with agricultural residue (corn stover) as a carbon source and an improvement in the bleaching of kraft pulp. Environmental pollution could thus be minimized because of a reduction in the use of chlorine as a bleaching agent.