A descriptive study of two small peer-directed mathematics groups in an elementary classroom.

The purpose of this study was to describe the behavior of children engaged in two different Peer Work Group (PWG) tasks and to search for patterns of behavior that relate to learning. The study was exploratory in nature and was designed to investigate the processes children use under different PWG task-structure conditions. Two groups of children in a 1st-2nd grade classroom were studied; each group worked for one week on each task and all interaction was videotaped. Detailed information about requests and responses was recorded onto a checklist. Pretests and posttests were administered for each task to assess gains and to search for relationships among tasks, behaviors, and learning. Results include identification of eleven task-related behaviors with differences across tasks in level of engagement for the following: Independent Seatwork, Group Discussion, Time Off-Task, Waiting for Peers, Cooperative Problem Solving, Approaching the Teacher, and Requesting Help. Patterns in the data for request-response behaviors agree with sociolinguistic theory regarding effective speakers . Significant differences were not found within or between groups and tasks on achievement measures. Implications are drawn regarding the influence of task structure on group process and children\u27s use of requesting behavior for obtaining elaborated responses from peers

Possible Interventions to Modify Aging

The programmed aging paradigm interprets aging as a function favored by natural selection at a supra-individual level. This function is implemented, according to the telomere theory, through mechanisms that operate through the subtelomere-telomere-telomerase system. After reviewing some necessary technical and ethical reservations and providing a concise description of aging mechanisms, this work considers interventions that could lead to the control of some highly disabling characteristics of aging, such as Alzheimer's and Parkinson's syndromes and age-related macular degeneration, and afterwards to a full control of aging up to a condition equivalent to that of the species defined as "with negligible senescence". The various steps needed for the development of such interventions are described along general lines

Aging of perennial cells and organ parts according to the programmed aging paradigm

If aging is a physiological phenomenon-as maintained by the programmed aging paradigm-it must be caused by specific genetically determined and regulated mechanisms, which must be confirmed by evidence. Within the programmed aging paradigm, a complete proposal starts from the observation that cells, tissues, and organs show continuous turnover: As telomere shortening determines both limits to cell replication and a progressive impairment of cellular functions, a progressive decline in age-related fitness decline (i.e., aging) is a clear consequence. Against this hypothesis, a critic might argue that there are cells (most types of neurons) and organ parts (crystalline core and tooth enamel) that have no turnover and are subject to wear or manifest alterations similar to those of cells with turnover. In this review, it is shown how cell types without turnover appear to be strictly dependent on cells subjected to turnover. The loss or weakening of the functions fulfilled by these cells with turnover, due to telomere shortening and turnover slowing, compromises the vitality of the served cells without turnover. This determines well-known clinical manifestations, which in their early forms are described as distinct diseases (e.g., Alzheimer's disease, Parkinson's disease, age-related macular degeneration, etc.). Moreover, for the two organ parts (crystalline core and tooth enamel) without viable cells or any cell turnover, it is discussed how this is entirely compatible with the programmed aging paradigm

Effect of Geospatial Uncertainty Borderization on Users' Heuristic Reasoning

Abstract. A set of mental strategies called "heuristics" – logical shortcuts that we use to make decisions under uncertainty – has become the subject of a growing number of studies. However, the process of heuristic reasoning about uncertain geospatial data remains relatively under-researched. With this study, we explored the relation between heuristics-driven decision-making and the visualization of geospatial data in states of uncertainty, with a specific focus on the visualization of borders, here termed "borderization". Therefore, we tested a set of cartographic techniques to visualize the boundaries of two types of natural hazards across a series of maps through a user survey. Respondents were asked to assess the safety and desirability of several housing locations potentially affected by air pollution or avalanches. Maps in the survey varied by "borderization" method, background color and type of information about uncertain data (e.g., extrinsic vs. intrinsic). Survey results, analyzed using a mixed quantitative-qualitative approach, confirmed previous suggestions that heuristics play a significant role in affecting users' map experience, and subsequent decision-making

Importance and Meaning of TERRA Sequences for Aging Mechanisms

Abstract: Any theory suggesting an adaptive meaning for aging implicitly postulates the existence of specific mechanisms, genetically determined and modulated, causing progressive decline of an organism. According to the subtelomere–telomere theory, each telomere is covered by a hood formed in the first cell of an organism having a size preserved at each subsequent duplication. Telomere shortening, which is quantitatively different for each cell type according to the telomerase regulation, causes the hood to slide on the subtelomere repressing it by the telomeric position effect. At this point, the theory postulates existence of subtelomeric regulatory sequences, whose progressive transcriptional repression by the hood should cause cellular alterations that would be the likely determinant of aging manifestations. However, sequences with characteristics of these hypothetical sequences have already been described and documented. They are the [sub]TElomeric Repeat-containing RNA (TERRA) sequences. The repression of TERRA sequences causes progressively: (i) down- or up-regulation of many other regulatory sequences; (ii) increase in the probability of activation of cell senescence program (blockage of the ability to replicate and very significant alterations of the cellular functions). When cell senescence program has not been triggered and the repression is partial, there is a partial alteration of the cellular functions that is easily reversible by telomerase activation. Location of the extremely important sequences in chromosomal parts that are most vulnerable to repression by the telomeric hood is evolutionarily unjustifiable if aging is not considered adaptive: this location must be necessarily adaptive with the specific function of determining aging of the cell and consequently of the whole organism

Provisión de equipamiento didáctico. Fichas de trabajo

El Ministerio de Educación de la Nación, en el marco del Plan Nacional de Educación Obligatoria y Formación Docente (Res 188/12) provee a todas las escuelas públicas de Educación Primaria un equipamiento didáctico para la enseñanza de las Ciencias Naturales. Dicho equipamiento consiste en: Material de laboratorio, Un carro para transportar dicho material dentro de la escuela, Una biblioteca de Ciencias Naturales. La llegada de este equipamiento junto con otras acciones que se llevan a cabo en las escuelas destinadas a mejorar la enseñanza, genera condiciones propicias para que el área de Ciencias Naturales recupere un lugar de relevancia dentro de la educación obligatoria desde los primeros años de la escuela primaria.Fichas técnicas para el uso de material de laboratori

Evolutionary Explanations of the “Actuarial Senescence in the Wild” and of the “State of Senility”

A large set of data suggests that progressive reduction of fitness and senile decay in vertebrates are in correlation with the decline of cell replication capacities. However, the limits in such capacities are hardly explained in evolutionarily terms by current gerontological theories that rule out fitness decline as something genetically determined and regulated, and therefore somehow favored by natural selection.Four theories are tested as possible explanations of the “increasing mortality with increasing chronological age in populations in the wild” (“IMICAW”[1]), alias “actuarial senescence in the wild”[2], and of the observed negative correlation between extrinsic mortality and the ratio between deaths due to intrinsic mortality and deaths due to extrinsic mortality. Only the theory attributing an adaptive value to IMICAW allows an evolutionary explanation for it and for the aforesaid inverse correlation, while the other three theories (“mutation accumulation”, “antagonistic pleiotropy”, and “disposable soma” th.) even predict a positive correlation.Afterwards, the same theories are tested as possible explanations for the “state of senility”[3], namely the deteriorated state of individuals in artificially protected conditions (captivity, civilization, etc.) at ages rarely or never observable in the wild. With the distinction between “damage resulting from intrinsic living processes”[4], alias “age changes”[5], and “age-associated diseases”[4,5], the same theory explaining IMICAW allows a rational interpretation of the first category of phenomena while another theory, the “mutation accumulation” hypothesis, gives an immediate interpretation for the second category.The current gerontological paradigm explaining the increasing mortality with increasing chronological age as consequence of insufficient selection should be restricted to the “age-associated diseases”. For IMICAW, it should be substituted with the concept of a physiologic phenomenon genetically determined by a balance of opposite selective pressures — strictly in terms of kin selection — and, for “age changes”, with the action of the same IMICAW-causing mechanisms at ages when selection becomes ineffective

Evolutionary explanations of the “actuarial senescence in the wild” and of the “state of senility

A large set of data suggests that progressive reduction of fitness and senile decay in vertebrates are in correlation with the decline of cell replication capacities. However, the limits in such capacities are hardly explained in evolutionarily terms by current gerontological theories that rule out fitness decline as something genetically determined and regulated, and therefore somehow favored by natural selection. Four theories are tested as possible explanations of the "increasing mortality with increasing chronological age in populations in the wild" ("IMICAW"[1]), alias "actuarial senescence in the wild"[2], and of the observed negative correlation between extrinsic mortality and the ratio between deaths due to intrinsic mortality and deaths due to extrinsic mortality. Only the theory attributing an adaptive value to IMICAW allows an evolutionary explanation for it and for the aforesaid inverse correlation, while the other three theories ("mutation accumulation", "antagonistic pleiotropy", and "disposable soma" th.) even predict a positive correlation. Afterwards, the same theories are tested as possible explanations for the "state of senility"[3], namely the deteriorated state of individuals in artificially protected conditions (captivity, civilization, etc.) at ages rarely or never observable in the wild. With the distinction between "damage resulting from intrinsic living processes"[4], alias "age changes"[5], and "age-associated diseases"[4,5], the same theory explaining IMICAW allows a rational interpretation of the first category of phenomena while another theory, the "mutation accumulation" hypothesis, gives an immediate interpretation for the second category. The current gerontological paradigm explaining the increasing mortality with increasing chronological age as consequence of insufficient selection should be restricted to the "age-associated diseases". For IMICAW, it should be substituted with the concept of a physiologic phenomenon genetically determined by a balance of opposite selective pressures -strictly in terms of kin selection -and, for "age changes", with the action of the same IMICAW-causing mechanisms at ages when selection becomes ineffective

\u3a0\u2011Stacking Signature in NMR Solution Spectra of Thiophene-Based Conjugated Polymers

Studies on conjugated polymers seldom report on their NMR characterization in solution. This paper shows how NMR experiments, both 1H NMR and routine 2D NMR spectra, can help in gaining a further insight into the aggregation behavior of conjugated polymers and could be used to flank the more employed solid-state NMR and other spectroscopy and microscopy techniques in the understanding of the aggregation processes. NMR spectroscopy allows distinguishing, within the class of poorly solvatochromic conjugated polymers, those highly prone to form \u3c0-stacked aggregates from the ones that have a low tendency toward \u3c0-stacking

Crimes involved in Russias Invasion of Ukraine

The current war in Ukraine began with Russia's invasion on February 24th, 2022. This act is widely regarded as violating the Ukrainian people's right to self-determination. It has also been regarded as an attempt to re-colonise Ukraine and to re-establish a Russian empire in Eastern Europe.This report will focus on Russia's alleged crimes in the war in Ukraine for the purposes of cohesion and to illustrate the multifaceted nature of the alleged war crimes and crimes against humanity committed by Russian forces. The invasion has already culminated in one of the harsher humanitarian crises of the century, where massive violations of human rights and international humanitarian law are at the core of the conflict. There have, however, also been reports of Ukraine's military violating the terms of the third Geneva Convention. Notably, a video emerged in which a Ukrainian soldier appears to kill a Russian soldier who had surrendered. The report will examine tactics reportedly used by Russia's military forces in its assault which violate Ukrainians' rights and are used to exert fear and submission. These include the targeting of civilian areas and infrastructure, the use of torture, rape, and the potential use of chemical weapons.