Scuola ed educazione naturalistica

Abstract

School and naturalistic education. In order that mankind may correctly fit in the balance of nature young people must be given the right scientific preparation during school years. This is why a better training of science teachers would be so important especially in Italy, where they come straight from University having followed various types of scientific degree courses, mainly theoretical, and with no special preparation for teaching.

The main basic requirement for a science teacher is that he has a solid preparation for laboratory but especially for field work. All other kinds of scientific and pedagogic knowledge is of course important but not as indispensable. It is therefore necessary to give science teachers the naturalistic training that University syllabuses do not provide for. At the same time work done inside the school should be supported from the outside by other organizations such as the Field Studies Council in England, or the « keeper-guides » of Israeli natural parks. In the present Italian school system one immediate step could be taken: teachers of « scientific observations » should not confine themselves to lecturing in classrooms but should spend most of their allotted time with their classes in the field or in the laboratory, in the same way as for instance teachers of « technical applications » do their teaching only in the workshop.     

Localized de novo phospholipid synthesis drives autophagosome biogenesis

ABSTRACT

During (macro)autophagy, cells form transient organelles, termed autophagosomes, to target a broad spectrum of substrates for degradation critical to cellular and organismal health. Driven by rapid membrane assembly, an initially small vesicle (phagophore) elongates into a large cup-shaped structure to engulf substrates within a few minutes in a double-membrane autophagosome. In particular, how autophagic membranes expand has been a longstanding question. Here, we summarize our recent work that delineates a pathway that drives phagophore expansion by localized de novo phospholipid synthesis. Specifically, we found that the conserved acyl-CoA synthetase Faa1 localizes to nucleated phagophores to locally activate fatty acids for de novo phospholipid synthesis in the neighboring ER. These newly synthesized phospholipids are then preferentially incorporated into autophagic membranes and drive the expansion of the phagophore into a functional autophagosome. In summary, our work uncovers molecular principles of how cells coordinate phospholipid synthesis and flux with autophagic membrane formation during autophagy.

Abbreviations: ACS: acyl-CoA synthestases; CoA: coenzyme A; ER: endoplasmic reticulum     

Isolating topics of high perceived difficulty school biology

Abstract

A technique devised to isolate topics of high perceived difficulty in a school biology syllabus is described. Results obtained from questioning school pupils, teachers, and university students indicate a large measure of agreement.     

Annapurna expedition game: applying molecular biology tools to learn genetics

ABSTRACT

In this paper, we present an activity called ‘Annapurna Expedition’ through which students should apply basic concepts of genetics to solve a worldwide pandemic disease. Players take the role of scientists, involved in a research to find out which pathogen causes this pandemic and which could be the best way to solve it. Students have the opportunity to use BLAST software as a scientific bioinformatic tool to discover the main game’ enigmas. The activity uses game-based science learning methodology. This methodology incorporates multiple tools and resources, rely on learning by doing, guiding learners through a path of events and into a way of thinking. It provides students to take information from many sources and make decisions, to deduce a game’s obstacles, to understand complex systems and to collaborate with other classmates.

The activity has been developed for a range of audiences, including high school students and pre-service teachers. A case study has been carried out with a group of 80 primary pre-service teachers from the Universitat Rovira i Virgili (URV) in Tarragona (Spain) in order to verify whether this activity was well designed, engage students and it is satisfactorily implemented.     

Influenza a distanza dei metalli sopra lo sviluppo di organismi vegetali inferiori

Summary

The Author relates about two new spontaneous stations of «Salvia Sclarea» in Sardinia, one of them is probably a shelter-station of another one pre-existing in a lower zone being about 200 meters from it. He refers about the actual area of the species; he describes the two stations and their relative plant-communities pointing out the indexes of plentifulness of the consociated species and comparing the biological spectra of them.

Wishing to research the reason why the species is so restive to spread spontaneously, while it is easily fitted for cultivation, the Author carries on a compared chemical-pedological study of the two stations with three other spontaneous stations near Sassari. He concludes that the «Salvia Sclarea» in sub-alkaline ground does not present particular exigences of chemical constitution, while it would meet difficulties to spread spontaneously in not very soft ground.

As the mentioned difficulties depend from particular conditions of aeration, temperature and humidity of the ground, the Author reserves to himself to make a further research in his next study.     

Is mainstream LCA linear?

Purpose

It is frequently mentioned in literature that LCA is linear, without a proof, or even without a clear definition of the criterion for linearity. Here we study the meaning of the term linear, and in relation to that, the question if LCA is indeed linear.

Methods

We explore the different meanings of the term linearity in the context of mathematical models. This leads to a distinction between linear functions, homogeneous functions, homogenous linear functions, bilinear functions, and multilinear functions. Each of them is defined in accessible terms and illustrated with examples.

Results

We analyze traditional, matrix-based, LCA, and conclude that LCA is not linear in any of the senses defined.

Discussion and conclusions

Despite the negative answer to the research question, there are many respects in which LCA can be regarded to be, at least to some extent, linear. We discuss a few of such cases. We also discuss a few practical implications for practitioners of LCA and for developers of new methods for LCI and LCIA.

     

Characteristics of schools with and without Gay-Straight Alliances

Abstract

Research shows that Gay-Straight Alliances (GSAs) are associated with school climate and student well-being, but it is unclear what school characteristics may account for some of these findings. The current study describes characteristics of schools with and without GSAs. Using a population-based sample of 1,360 California public high schools, inferential statistics show that schools with larger enrollment, more experienced teachers, and lower pupil/teacher ratios were more likely to have GSAs. In addition, among schools with GSAs, larger enrollment, more experienced teachers, fewer socioeconomically disadvantaged students, and higher academic achievement are among the factors related to a longer presence of GSAs. Implications for GSA and policy implementation, as well as the importance of accounting for school characteristics in research on GSAs are discussed.     

Genomic duplication problems for unrooted gene trees

Background

Discovering the location of gene duplications and multiple gene duplication episodes is a fundamental issue in evolutionary molecular biology. The problem introduced by Guigó et al. in 1996 is to map gene duplication events from a collection of rooted, binary gene family trees onto theirs corresponding rooted binary species tree in such a way that the total number of multiple gene duplication episodes is minimized. There are several models in the literature that specify how gene duplications from gene families can be interpreted as one duplication episode. However, in all duplication episode problems gene trees are rooted. This restriction limits the applicability, since unrooted gene family trees are frequently inferred by phylogenetic methods.

Results

In this article we show the first solution to the open problem of episode clustering where the input gene family trees are unrooted. In particular, by using theoretical properties of unrooted reconciliation, we show an efficient algorithm that reduces this problem into the episode clustering problems defined for rooted trees. We show theoretical properties of the reduction algorithm and evaluation of empirical datasets.

Conclusions

We provided algorithms and tools that were successfully applied to several empirical datasets. In particular, our comparative study shows that we can improve known results on genomic duplication inference from real datasets.

     

Mining cancer biology through bioinformatic analysis of proteomic data

ABSTRACT

Introduction: Discovery proteomics for cancer research generates complex datasets of diagnostic, prognostic, and therapeutic significance in human cancer. With the advent of high-resolution mass spectrometers, able to identify thousands of proteins in complex biological samples, only the application of bioinformatics can lead to the interpretation of data which can be relevant for cancer research.

Areas covered: Here, we give an overview of the current bioinformatic tools used in cancer proteomics. Moreover, we describe their applications in cancer proteomics studies of cell lines, serum, and tissues, highlighting recent results and critically evaluating their outcomes.

Expert opinion: The use of bioinformatic tools is a fundamental step in order to manage the large amount of proteins (from hundreds to thousands) that can be identified and quantified in a cancer biological samples by proteomics. To handle this challenge and obtain useful data for translational medicine, it is important the combined use of different bioinformatic tools. Moreover, a particular attention to the global experimental design, and the integration of multidisciplinary skills are essential for best setting of tool parameters and best interpretation of bioinformatics output.     

Is 24-hour energy intake greater during night shift compared to non-night shift patterns? A systematic review

ABSTRACT

Introduction: Epidemiological studies show that shift workers are at increased risk of cardiovascular diseases, metabolic dysfunction, diabetes, and obesity. Previous research has shown no difference in energy intake between night and day shifts only; however, it remains unclear whether other non-night shift patterns are different to night shift.

Objectives: We investigated whether energy intake of night-shift workers differed from other shift patterns using calorimetry, food diary or food recall over 24-hour periods.

Methods: A systematic review was conducted searching CINAHL, MEDLINE, Web of Science, Embase and PsycINFO databases for observational and interventional studies measuring energy intake in real or simulated shift work. Energy intake was extracted to compare night, day, afternoon/evening and rotating shift work cases.

Results: After duplicate removal, we screened 1057 abstracts and 68 full-text articles were assessed for eligibility of which 15 studies met the inclusion criteria. All studies were cross-sectional and case–control designs in shift workers. Risk of bias assessment showed a low to moderate risk of bias in the majority of studies. There was no difference in energy intake between night-shift work and non-night shift patterns including early morning, day and afternoon/evening shifts. Night-shift workers did not favor particular macronutrients in comparison to other shift schedules.

Conclusions: Energy and macronutrient intake were not detectably different in night shift compared to other shift patterns. Shift work patterns were heterogeneous which likely impacted on dietary assessment timings and computation of 24-h energy intake. Future studies should examine shift schedules with precise circadian timing of food consumption to determine if differences exist in energy and macronutrient intake between different shift patterns.     

Linking specification to differentiation: From proneural genes to the regulation of ciliogenesis

Much of developmental biology is concerned with the processes by which cells become committed to particular fates in a regulated fashion, whereas cell biology addresses, among other things, the variety of differentiated forms and functions that cells can acquire. One open question is how the regulators of the former process lead to attainment of the latter. “High-level” regulators of cell fate specification include the proneural factors, which drive cells to commit as precursors in the sensory nervous system. Recent research has concentrated on the gene expression events downstream of proneural factor function. Here we summarize this research and describe our own research that has provided clear links between a proneural factor, atonal and the cell biological program of ciliogenesis, which is a central aspect of sensory neuron differentiation.     

Preparedness as a counter-memory. School desegregation,social chances and life chances

ABSTRACT

How should we understand the conundrum of love for the segregated school – a system built to keep you in your place? In Gone Home. Race and Roots through Appalachia, Karida L. Brown looks at African American teacher’s work in segregated schools and shows how desegregation could be felt in both gains and losses in the black community. Those teachers prepared their students for a world of integration without freedom. This essay proposes a counter-memory of segregation, a relational agency of teachers past that remains to this day. Former students’ commemoration of teachers, principals, and schools dating from the time of institutionalized racial exclusion works as a symbolic reminder in a still-racist world, representing not only the need to be prepared, but also to stay prepared.     

A population approach to vegetation structure

Abstract

A synthesis is presented of some research results on the structure and dynamics of populations with respect to the phytocoenosis structure. The first aspects to be considered are concerned with the dynamism, distribution and reproductive strategy of Anemone nemorosa: the vegetation structure either favors or inhibits the various reproductive strategies, thereby influencing the distribution pattern of the species. The second area of the present study is the demography and quantitative structure of Cytisus sessilifolius populations with respect to the problematic of secondary successions: the first results obtained open up interesting prospectives on the relationship between the vegetation dynamics and the frutescent populations structure.     

Evaluating reasons for biased sex ratios in Crustacea

ABSTRACT

While equal ratios of males and females are normal, crustacean sex ratios are frequently biased. Here I review potential reasons for sex ratio biases in animals, and evaluate how likely they apply to crustaceans. I introduce crustacean examples and highlight promising crustacean taxa for future studies where examples are lacking. I conclude that ecological differences between the sexes appear to be the dominant reason for sex ratio bias in crustaceans. Major life history patterns limit the importance of evolutionary drivers to sedentary taxa with limited dispersal. Still largely unresolved is the question whether females can bias their offspring sex ratio, and given the diversity of sex determining systems, answers will vary from case to case.

Abbreviations: LMC: local mate competition; LSC: local sperm competition.     

Fortress Holland? Support for ethnocentric policies among the 1994‐electorate of The Netherlands

Abstract

The Dutch have a long tradition of hospitality towards ethnic immigrants. In the nineties, however, quite dramatic changes have taken place among the Dutch. The central question addressed in this contribution is: to what extent do specific categories within the electorate favour ethnocentric policies? This question is answered by deducing hypotheses that are tested using recent data polled within the framework of the Dutch National Election Studies. Our crucial conclusion is that a rather widespread support for ethnocentric policies is present in contemporary Dutch society, especially among manual labourers, self‐employed and lowly educated people, but also among young cohorts and among modal income categories.     

Chimpanzee included in the genus Homo? How biology teachers from three Latin American countries conceive it

ABSTRACT

Despite scientific evidence suggesting close phylogenetic relationship between chimpanzees and humans, the inclusion of these apes in the genus Homo is controversial. Several tools have been used to analyse this issue such as fossils, molecular clock and genome. This work intended to understand the biology teachers’ conceptions about the humans’ and chimpanzee’s position. It was carried out in three countries with contrasting secularism conditions: Argentina, Brazil and Uruguay. Teachers were asked to answer to the BIOHEAD-CITIZEN project question: ‘The Chimpanzee should be included in the genus Homo, notably because 98.5% of its DNA is identical to that of Homo sapiens’. Results were analysed within the KVP model framework and the Barbour’s four categories of relationship between science knowledge and religion. Most questioned teachers (80%) of the three countries rejected the idea of including the chimpanzee in the genus Homo (86% of Argentinians, 71% of Brazilians and 71% Uruguayans), suggesting the conception of human beings having a special position in relation to other animal species. This study also indicates that the training of biology teachers needs to be analysed in the three countries to understand how teachers-to-be are being trained and evaluate their knowledge regarding molecular biology, phylogeny and evolution.