False confidence: are we ignoring significant sources of uncertainty?

The International Journal of Life Cycle Assessment - With the increasing use of stochastic simulation, also known as Monte Carlo simulation, to perform uncertainty analysis in life cycle...     

Abnormal cervical smears: are we in for an epidemic?

A retrospective study was conducted to examine the pattern of a disturbing increase in abnormal cervical smears in one health district. Past records over fifteen years (1965-79) were analysed to produce pick up rates according to age, screening state, severity of lesion, and area of residence. Main findings included an increased pick up rate in unscreened (5.8 to 12.9/1000 smears) and screened (0.9 to 3.6/1000 smears) women. The order of increase was proportionately much higher in women under 40 years. The only significant epidemiological variable in the catchment area was a substantial population increase, overweighted by the younger age groups. The principal conclusion of the study was that the increased pick up rates of abnormal cervical smears in the district reflected a true increase in the incidence of premalignant lesions of the cervix. Screening efforts aided by computerisation should be examined nationwide in order to reach high risk groups and thus try to prevent an increase in carcinoma of the cervix.     

Why are there more arboreal ant species in primary than in secondary tropical forests?

1.?Species diversity of arboreal arthropods tends to increase during rainforest succession so that primary forest communities comprise more species than those from secondary vegetation, but it is not well understood why. Primary forests differ from secondary forests in a wide array of factors whose relative impacts on arthropod diversity have not yet been quantified. 2.?We assessed the effects of succession-related determinants on a keystone ecological group, arboreal ants, by conducting a complete census of 1332 ant nests from all trees with diameter at breast height?≥?5?cm occurring within two (unreplicated) 0·32-ha plots, one in primary and one in secondary lowland forest in New Guinea. Specifically, we used a novel rarefaction-based approach to match number, size distribution and taxonomic structure of trees in primary forest communities to those in secondary forest and compared the resulting numbers of ant species. 3.?In total, we recorded 80 nesting ant species from 389 trees in primary forest but only 42 species from 295 trees in secondary forest. The two habitats did not differ in the mean number of ant species per tree or in the relationship between ant diversity and tree size. However, the between-tree similarity of ant communities was higher in secondary forest than in primary forest, as was the between-tree nest site similarity, suggesting that secondary trees were more uniform in providing nesting microhabitats. 4.?Using our rarefaction method, the difference in ant species richness between two forest types was partitioned according to the effects of higher tree density (22·6%), larger tree size (15·5%) and higher taxonomic diversity of trees (14·3%) in primary than in secondary forest. The remaining difference (47·6%) was because of higher beta diversity of ant communities between primary forest trees. In contrast, difference in nest density was explained solely by difference in tree density. 5.?Our study shows that reduction in plant taxonomic diversity in secondary forests is not the main driver of the reduction in canopy ant species richness. We suggest that the majority of arboreal species losses in secondary tropical forests are attributable to simpler vegetation structure, combined with lower turnover of nesting microhabitats between trees.     

Phenology of fleshy fruits in a wet sclerophyll forest in southeastern Australia: are birds an important influence?

Summary The hypothesis that seasonality in the production of fleshy fruits in temperate regions is the result of selection by avian seed dispersal agents or avian seed predators was tested in a temperate wet sclerophyll forest in south-eastern Australia. I determined whether ten common fleshy-fruited species produced fruits when potential avian seed dispersers were most abundant or avian seed predators were least abundant. The season of fruit production was not correlated with avian disperser abundance nor with seasonal changes in avian seed predators. Peak fruiting occurred during autumn but fruit-eating birds were equally abundant from spring through to autumn. Avian seed predators (parrots) did not show any seasonal variation in abundance. If dispersers are influencing fruiting seasonality in wet sclerophyll forest, it is likely that changes in social behaviour and feeding patterns of dispersers during autumn, rather than increases in abundance, will be an important influence on fruiting patterns in wet sclerophyll forest. However, environmental and life history factors may also influence phenology.     

How important are terrestrial organic carbon inputs for secondary production in freshwater ecosystems?

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Detail in network models of epidemiology: are we there yet?

Network models of infectious disease epidemiology can potentially provide insight into how to tailor control strategies for specific regions, but only if the network adequately reflects the structure of the region's contact network. Typically, the network is produced by models that incorporate details about human interactions. Each detail added renders the models more complicated and more difficult to calibrate, but also more faithful to the actual contact network structure. We propose a statistical test to determine when sufficient detail has been added to the models and demonstrate its application to the models used to create a synthetic population and contact network for the USA.     

Macrophytes in tropical shallow lakes: An important food item to benthic entomofauna or an underused resource?

Although macrophytes are known to increase benthic diversity in lakes, the importance of this resource as food for the insects living at the bottom of these ecosystems are still poorly understood. This study assessed the diets of benthic Chironomidae and Campsurus (Ephemeroptera) in two environments: a lake with macrophytes (M+) and another without macrophytes (M?). We expected a differential use of food resources in M+, where plant tissue is particularly important for the aquatic insects’ diet. The diet of 734 individuals from 16 taxa were analyzed. Contrary to expectations, benthic insects consumed low amounts of plant tissue. This finding led us to investigate whether the presence of macrophytes in lakes would indirectly contribute to the benthic insects’ feeding, as more food resources were explored in M+ and a spatial variation of resources intake was observed in this lake, in contrast to the homogeneous feeding in M?. We highlight that macrophytes were responsible for the organic matter build‐up in the sediment, especially at the lake region dominated by these plants, and contributed to increase the deposition of high‐quality amorphous organic matter, which favored taxa in M+ that fed exclusively on this item. The lower diversity of food items exploited in M?, and the Tanypus alga‐based diet in this lake, indicates the low quality of organic resources in its sediment. Although macrophytes were indirectly beneficial for benthic insects’ feeding, we found that this is not an attractive resource for prompt ingestion by most benthic taxa.     

The evolution of conspicuous facultative mimicry in octopuses: an example of secondary adaptation?

The ‘Mimic Octopus’Thaumoctopus mimicus Norman & Hochberg, 2005 exhibits a conspicuous primary defence mechanism (high‐contrast colour pattern during ‘flatfish swimming’) that may involve facultative imperfect mimicry of conspicuous and/or inconspicuous models, both toxic and non‐toxic (Soleidae and Bothidae). Here, we examine relationships between behavioural and morphological elements of conspicuous flatfish swimming in extant octopodids (Cephalopoda: Octopodidae), and reconstructed ancestral states, to examine potential influences on the evolution of this rare defence mechanism. We address the order of trait distribution to explore whether conspicuous flatfish swimming may be an exaptation that usurps a previously evolved form of locomotion for a new purpose. Contrary to our predictions, based on the relationships we examined, flatfish swimming appears to have evolved concurrently with extremely long arms, in a clade of sand‐dwelling species. The conspicuous body colour pattern displayed by swimming T. mimicus may represent a secondary adaptation potentially allowing for mimicry of a toxic sole, improved disruptive coloration, and/or aposematic coloration. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 68–77.     

How short are we on the goal line of estimating insect-plant interaction in a hyperdiverse tropical environment?

Journal of Insect Conservation - In ecology, dealing with sample design is a constant challenge, especially in interaction networks, where most studies suffer from undersampling. Different sampling...     

Two Decades of Molecular Ecology: where are we and where are we heading?

The twentieth anniversary of the journal Molecular Ecology was celebrated with a symposium on the current state and the future directions of the field. The event, organized by Tim Vines and Loren Rieseberg, took place on the opening day of the First Joint Congress on Evolutionary Biology organized by the American Society of Naturalists (ASN), the Canadian Society for Ecology and Evolution (CSEE), the European Society for Evolutionary Biology (ESEB), the Society for the Study of Evolution (SSE) and the Society of Systematic Biologists (SSB) in Ottawa (Canada) from 6–10 July 2012. The get together of these five societies created a truly international and exciting “Evolution conference” and the ideal framework for the Molecular Ecology symposium. Its thirteen talks were grouped into the five different subject areas of the journal: Speciation and Hybridization; Landscape Genetics, Phylogeography and Conservation; Ecological Genomics and Molecular Adaptation; Kinship, Parentage and Behaviour; Ecological Interactions. Each session was followed by a panel discussion on the future direction of the subfield. That more than 300 colleagues registered for this special symposium illustrates the broad interest in, and appreciation of, molecular ecology – both the field and the journal.     

Ultrasonographic soft markers of aneuploidy in second trimester: are we lost?

Chromosomal abnormalities occur in 0.1% to 0.2% of live births, and the most common clinically significant aneuploidy among live-born infants is Down syndrome (trisomy 21). Other sonographically detectable aneuploidies include trisomy 13, 18, monosomy X, and triploidy. Second-trimester ultrasound scan detects 2 types of sonographic markers suggestive of aneuploidy. Markers for major fetal structural abnormalities comprise the first type; the second type of markers are known as "soft markers" of aneuploidy. These latter markers are nonspecific, often transient, and can be readily detected during the second-trimester ultrasound. The most commonly studied soft markers of aneuploidy include a thickened nuchal fold, rhizomelic limb shortening, mild fetal pyelectasis, echogenic bowel, and echogenic intracardiac focus and choroid plexus cyst. There is a great deal of interest in the ultrasound detection of aneuploidy, as evidenced by the large number of publications in the literature on this topic. Unfortunately, studies evaluating the significance of the soft markers of aneuploidy vary widely and show contradictory results. In this article, we review the most common ultrasonographic soft markers used to screen aneuploidy and discuss ultrasonographic technique and measurement criteria for the detection of soft markers. We also review the clinical relevance of soft markers to aneuploidy risk assessment and evidence-based strategies for the management of affected pregnancies with each of these markers in light of current literature.     

Clinical applications of mass spectrometry-based proteomics in cancer: Where are we?

Tumor tissue processing methodologies in combination with data-independent acquisition mass spectrometry (DIA-MS) have emerged that can comprehensively analyze the proteome of multiple tumor samples accurately and reproducibly. Increasing recognition and adoption of these technologies has resulted in a tranche of studies providing novel insights into cancer classification systems, functional tumor biology, cancer biomarkers, treatment response and drug targets. Despite this, with some limited exceptions, MS-based proteomics has not yet been implemented in routine cancer clinical practice. Here, we summarize the use of DIA-MS in studies that may pave the way for future clinical cancer applications, and highlight the role of alternative MS technologies and multi-omic strategies. We discuss limitations and challenges of studies in this field to date and propose steps for integrating proteomic data into the cancer clinic.     

50 Years of Women in Cell Biology: Where have we been? Where are we going?

It’s been 50 years since Women in Cell Biology (WICB) was founded by junior women cell biologists who found themselves neither represented at the American Society for Cell Biology (ASCB) presentations nor receiving the information, mentoring, and sponsorship they needed to advance their careers. Since then, gender parity at ASCB has made significant strides: WICB has become a standing ASCB committee, women are regularly elected president of the ASCB, and half the symposia speakers are women. Many of WICB’s pioneering initiatives for professional development, including career panels, workshops, awards for accomplishments in science and mentoring, and career mentoring roundtables, have been incorporated and adapted into broader “professional development” that benefits all members of ASCB. The time has passed when we can assume that all women benefit equally from progress. By strategically, thoughtfully, and honestly recognizing the challenges to women of the past and today, we may anticipate those new challenges that will arise in the next 50 years. WICB, in collaboration with the ASCB, can lead in data collection and access and can promote diversity, equity, and inclusion. This work will be a fitting homage to the women who, half a century ago, posted bathroom stall invitations to the first Women in Cell Biology meetup.     

Ecological integrity assessment as a metric of biodiversity: are we measuring what we say we are?

As the recognition of the importance of biological diversity in biological conservation grows, an ongoing challenge is to develop metrics that can be used for effective conservation and management. The ecological integrity assessment has been proposed as such a metric. It is held by some to measure species composition, diversity, and habitat quality, as well as ecosystem structure, composition, and function. The methodology relies on proxy variables that include data on landscape characteristics such as patch size, abiotic factors such as hydrology, and some features of vegetation structure and composition. We suggest that the measure is flawed on four levels. First, its putative representation of general ecological form and function, and its lack of specific detail about how it actually represents those attributes, leaves the metric without the focus needed to be useful for measuring ecological features on the ground and testing associated hypotheses and predictions. Second, the proxy variables used to represent biological diversity, such as habitat (vegetation) metrics and vascular plant species diversity, are not empirically correlated with diversity of a range of taxa or of other components of the biota. Third, like other ecological indices that integrate many distinct features, the ecological integrity index is subject to the loss of information in its condensation of multi-dimensional variability into a one-dimensional index, and it may be subject to systematic bias from the conversion of raw data into categorical scores. Fourth, the sampling protocols are at risk of sampling bias, observer bias, and measurement error, any of which can confound the estimation of conservation value. In terms of biological diversity, the methodology produces an unreliable estimate of the number of vascular plant species and their relative percentages of occurrence, and an absence of any protocols for taxa other than plants. For these reasons we believe that ecological integrity assessment is currently of limited value as a measure of site-specific biological diversity and its change over time. A considerable amount of investigation is needed in order to have confidence in the results of an ecological integrity assessment, especially if it is to be used for regulatory purposes. We suggest further refinements and discuss alternative measures of biological diversity that provide reliable metrics for assessing change. A thoughtful choice among measures can help to identify the most appropriate assessment for conservation decisions.     

Pim kinases in hematological malignancies: where are we now and where are we going?

The proviral insertion in murine (PIM) lymphoma proteins are a serine/threonine kinase family composed of three isoformes: Pim-1, Pim-2 and Pim-3. They play a critical role in the control of cell proliferation, survival, homing and migration. Recently, overexpression of Pim kinases has been reported in human tumors, mainly in hematologic malignancies. In vitro and in vivo studies have confirmed their oncogenic potential. Indeed, PIM kinases have shown to be involved in tumorgenesis, to enhance tumor growth and to induce chemo-resistance, which is why they have become an attractive therapeutic target for cancer therapy. Novel molecules inhibiting Pim kinases have been evaluated in preclinical studies, demonstrating to be effective and with a favorable toxicity profile. Given the promising results, some of these compounds are currently under investigation in clinical trials. Herein, we provide an overview of the biological activity of PIM-kinases, their role in hematologic malignancies and future therapeutic opportunities.