Ant colony development and transfer of juvenile hormone by trophallaxis

Trabalho de projeto do mestrado em Economia (Economia Financeira), apresentado à Faculdade de Economia da Universidade de Coimbra, sob a orientação de António Portugal Duarte.A hipótese Export-led-Growth defende que a promoção das exportações é fundamental para o reforço do crescimento económico. Contudo, nenhum consenso foi alcançado sobre a causalidade entre as duas variáveis. Este trabalho tem como objetivo reexaminar a hipótese Export-led-Growth em Portugal para o período 1970-2012, aplicando técnicas econométricas usuais para o estudo de séries temporais, como a análise de estacionaridade e cointegração das variáveis, bem como a estimação de um modelo de vetores de correção dos erros. O estudo revela a existência de uma relação de equilíbrio de longo- prazo entre as exportações e o PIB, e valida a hipótese Export-led-Growth para o caso Português. Com o objetivo de obter resultados mais detalhados, procurou-se ainda avaliar o impacto das exportações de produtos da indústria transformadora e não-transformadora no crescimento económico, utilizando dois modelos de vetores auto-regressivos bivariados. A estimação dos modelos revela um impacto positivo das exportações de produtos da indústria transformadora no PIB e um efeito “limitador” das exportações de produtos não transformados

Standard methods for Apis mellifera anatomy and dissection

An understanding of the anatomy and functions of internal and external structures is fundamental to many studies on the honey bee Apis mellifera. Similarly, proficiency in dissection techniques is vital for many more complex procedures. In this paper, which is a prelude to the other papers of the COLOSS BEEBOOK, we outline basic honey bee anatomy and basic dissection techniques

Oral transfer of chemical cues, growth proteins and hormones in social insects.

Social insects frequently engage in oral fluid exchange - trophallaxis - between adults, and between adults and larvae. Although trophallaxis is widely considered a food-sharing mechanism, we hypothesized that endogenous components of this fluid might underlie a novel means of chemical communication between colony members. Through protein and small-molecule mass spectrometry and RNA sequencing, we found that trophallactic fluid in the ant Camponotus floridanus contains a set of specific digestion- and non-digestion related proteins, as well as hydrocarbons, microRNAs, and a key developmental regulator, juvenile hormone. When C. floridanus workers' food was supplemented with this hormone, the larvae they reared via trophallaxis were twice as likely to complete metamorphosis and became larger workers. Comparison of trophallactic fluid proteins across social insect species revealed that many are regulators of growth, development and behavioral maturation. These results suggest that trophallaxis plays previously unsuspected roles in communication and enables communal control of colony phenotypes

Stage-Specific Effects of Population Density on the Development and Fertility of the Western Tarnished Plant Bug, Lygus hesperus

The western tarnished plant bug Lygus hesperus Knight (Heteroptera: Miridae), a major pest of cotton and other key economic crops, was tested for its sensitivity to population density during nymph and adult stages. Nymphs reared to adulthood under increasing densities in laboratory conditions exhibited incremental delays in maturation, heightened mortality rates, and reductions in body mass and various size parameters. In contrast, gonadal activity in both males and females rose with initial density increases. Supplemental nutrients provided to the nymphs failed to offset the negative effects of high density, suggesting that contact frequency, rather than resource partitioning, may be the primary stress. Unlike nymphs, newly eclosed adults exposed to increasing population densities did not suffer negative physiological effects; body mass, mortality rates and patterns of ovipositional activity were unchanged. Collectively, these results indicate that population density can dramatically influence Lygus development, but the specific effects are stage-dependent

Incidence, risk factors and outcomes of checkpoint inhibitor-induced liver injury: a 10-year real-world retrospective cohort study

AbstractsBackground and Aims: Checkpoint inhibitors (CPI) are accounting for increasing number of drug-induced liver injury (DILI) cases. We aimed to determine the incidence rate and risk factors associated with checkpoint inhibitor-induced liver injury (ChILI).Method: Prescription event monitoring was performed on all melanoma and renal cancer patients who received CPI at a tertiary centre between 2011 and 2021. ChILI cases were identified using the definitions, grading and causality assessment methods validated for DILI. We assessed risk factors associated with ChILI in CPInaïve patients using multivariable logistic regression model. Consecutive patients with suspected ChILI from two other tertiary centres were adjudicated and combined for case characterization and outcomes of ChILI.Results: Out of 432 patients received CPI over 10 years, ChILI occurred in 38 (8.8%) with an overall incidence rate of 11.5 per 1,000 patient-months (95% CI 8.2-15.8). Probability of ChILI was highest in combination therapy (32%) with no new events occurred beyond 135 days of treatment. Risk factor analysis showed that combination therapy, female sex, higher baseline alanine transferase level and lower baseline alkaline phosphatase level were independently associated with higher risk of ChILI. In total, 99 patients were adjudicated to have ChILI from three centres.Although Common Terminology Criteria for Adverse Events (CTCAE) classified 20 patients (20.2%) to have ‘life-threatening’ grade 4 hepatitis, ChILI severity was graded as mild in 45 (45.5%) and moderate in the remaining 54 (54.5%) cases.Conclusion: The risk of ChILI in real-world is higher than previously reported. Among patients receiving dual CPI, this risk falls markedly after four and half 7 months. As CTCAE overestimates its clinical severity, case-definition, evaluation and management of ChILI should be revised to harmonise care

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

Molecular traces of alternative social organization in a termite genome

Although eusociality evolved independently within several orders of insects, research into the molecular underpinnings of the transition towards social complexity has been confined primarily to Hymenoptera (for example, ants and bees). Here we sequence the genome and stage-specific transcriptomes of the dampwood termite Zootermopsis nevadensis (Blattodea) and compare them with similar data for eusocial Hymenoptera, to better identify commonalities and differences in achieving this significant transition. We show an expansion of genes related to male fertility, with upregulated gene expression in male reproductive individuals reflecting the profound differences in mating biology relative to the Hymenoptera. For several chemoreceptor families, we show divergent numbers of genes, which may correspond to the more claustral lifestyle of these termites. We also show similarities in the number and expression of genes related to caste determination mechanisms. Finally, patterns of DNAmethylation and alternative splicing support