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Tree growth and longevity trade-offs fundamentally shape the terrestrial carbon balance. Yet, we lack a unified understanding of how such trade-offs vary across the world's forests. By mapping life history traits for a wide range of species across the Americas, we reveal considerable variation in life expectancies from 10 centimeters in diameter (ranging from 1.3 to 3195 years) and show that the pace of life for trees can be accurately classified into four demographic functional types. We found emergent patterns in the strength of trade-offs between growth and longevity across a temperature gradient. Furthermore, we show that the diversity of life history traits varies predictably across forest biomes, giving rise to a positive relationship between trait diversity and productivity. Our pan-latitudinal assessment provides new insights into the demographic mechanisms that govern the carbon turnover rate across forest biomes.

There has been a policy push in K-12 educational settings towards personalized learning in the last decade. Commercial platforms and learning designers have responded, offering learning tools to support teaching and learning through data-driven insights and recommendations. Trending towards the augmentation or replacing human teachers with non-human technology, this paper argues that personalized learning with human teachers is an entirely different process from personalization with digital twins. Drawing on new materialist thinking, it explores the impacts and implications for discourse concerning teacher quality and disadvantages within educational systems. It clarifies the conflation of the terms "personalized learning" and "personalization" to illuminate the power, positionality, and privilege enabled for some, in conflating terms in Australian educational policy.

In this article we present our findings regarding of providing online educational activities, delivered by six adults, during 13 weeks (first semester 2020) to 15 children aging from 5 to 7 (the Beaver scouts), on a non-formal education context. The activities combined guided play and problem-based learning activities. Our research objective was to analyzed the method followed, uncovering the dynamics the drove the activities and the consequences. We followed an action research approach in order to understand the feedback loops present in the delivery of online educational activities. The data was collected from the minutes of the meetings, the activities' plans and the notes taken from observations of the online activities and notes taken during the debriefing activities. We analyzed the data by means of a systemic analysis. Our findings are: 1) The diversification of activities (physical, artistic, and social) provided by the leaders and the parent´s support and participation fostered the children engagement and motivation to learn. 2) The continuous improvement of the teach and learning techniques and the right use of IT tools, facilitated the communication and the delivery of meaningful online activities.

This article presents the findings related to an exploratory study of the systemic impacts of the COVID-19 pandemic on the studies of graduate students of Brazil. It was sent a survey to 38 students who attended a University of São Paulo graduate course during the first semester of 2021. An exploratory sequential mixed method approach was followed. Quantitative and qualitative data was collected using questionnaires. The quantitative data was analyzed through descriptive statistics. The qualitative data was examined following a language processing method. The insights gained from both kinds of data were connected using a causal loop diagram. It was found that home confinement was the factor that created the main barriers to learning. In addition, digital fatigue, inadequate teaching strategies and the limitation of video conferencing tools also impacted negatively on learning. On the other hand, the pandemic also brought learning opportunities: the students took advantage of courses, webinars and conferences offered during the pandemic. In addition, the students developed new IT and communication skills.

CRISPR-Cas12a is a powerful RNA-guided genome-editing system that generates double-strand DNA breaks using its single RuvC nuclease domain by a sequential mechanism in which initial cleavage of the non-target strand is followed by target strand cleavage. How the spatially distant DNA target strand traverses toward the RuvC catalytic core is presently not understood. Here, continuous tens of microsecond-long molecular dynamics and free-energy simulations reveal that an α-helical lid, located within the RuvC domain, plays a pivotal role in the traversal of the DNA target strand by anchoring the crRNA:target strand duplex and guiding the target strand toward the RuvC core, as also corroborated by DNA cleavage experiments. In this mechanism, the REC2 domain pushes the crRNA:target strand duplex toward the core of the enzyme, while the Nuc domain aids the bending and accommodation of the target strand within the RuvC core by bending inward. Understanding of this critical process underlying Cas12a activity will enrich fundamental knowledge and facilitate further engineering strategies for genome editing.

This study investigated the effects of recurrent water deficit on drought tolerance traits in black pepper (Piper nigrum L.) ʻBragantinaʼ. Plants were subjected to three cycles of water deficit followed by recovery periods. Water deficit reduced stomatal conductance, photosynthesis, transpiration, and water potential while increasing water-use efficiency. In addition, intercellular CO2 concentration, leaf temperature, root starch, and adaptive morphological characteristics in leaves and roots increased. Despite these adaptations, plants did not recover vegetative growth after rehydration. The primary tolerance mechanisms observed included increased abaxial epidermis thickness, stomatal density, fine roots, periderm thickness, and starch accumulation in roots. Although gas exchange and leaf water potential were restored, vegetative growth did not fully recover. This study highlights the response of black pepper to recurrent water stress and the underlying mechanisms of its drought tolerance.

In this article, we presented our findings regarding an online project-based learning course, delivered to 64 students from the Federal University of Sao Paulo, Brazil, during the COVID-19 pandemic, in the second semester of 2021. The course had the goal of teaching Project Management by means of a competition (the Data Science Olympics). Our goal was to investigate the systemic impacts of the competition on learning. Data was collected by means of a questionnaire and from comments posted on the teams' websites. We followed a convergent parallel mixed methods approach. We analyzed the data using a causal loop diagram to connect the insights gained with quantitative and qualitative results. Our findings were as follows: (1) The use of competition in a project-based learning centered course helped the students to develop project management and data science skills, and fostered metacognition and knowledge sharing opportunities. (2) The Data Science Olympics increased the students' intrinsic motivation to learn. (3) The project-based teaching practices (scaffolding the students' learning, giving meaningful feedback to the students, and managing the activities) facilitated the students' learning. (4) The problems the students faced throughout the Project (dropouts, communication problems, lack of commitment, difficulty scheduling online team meetings) impacted negatively on the students' motivation.

In this case study, we present our findings regarding a massive open online Scratch programming course. The course, which followed a project-based learning approach, was delivered from July 4 to 30, 2022 to 186 students in Brazil. The students were challenged to develop individual coding projects. Our research goal was to investigate teaching and learning course dynamics. We followed a convergent parallel mixed-method approach. We collected quantitative and qualitative data by means of questionnaires. We were able to identify five intertwined feedback loops that drove the educational process. Our main findings are as follows: 1) The development of coding skills was driven by the effort of watching video-lectures, remixing of peers' codes, and by sharing knowledge between the students. 2) The project-based learning approach created opportunities for the students to collaborate and exchange ideas.

Cas13a is a recent addition to the CRISPR-Cas toolkit that exclusively targets RNA, which makes it a promising tool for RNA detection. It utilizes a CRISPR RNA (crRNA) to target RNA sequences and trigger a composite active site formed by two Higher Eukaryotes and Prokaryotes Nucleotide (HEPN) domains, cleaving any solvent-exposed RNA. In this system, an intriguing form of allosteric communication controls the RNA cleavage activity, yet its molecular details are unknown. Here, multiple-microsecond molecular dynamics simulations are combined with graph theory to decipher this intricate activation mechanism. We show that the binding of a target RNA acts as an allosteric effector, by amplifying the communication signals over the dynamical noise through interactions of the crRNA at the buried HEPN1-2 interface. By introducing a novel Signal-to-Noise Ratio (SNR) of communication efficiency, we reveal critical allosteric residues-R377, N378, and R973-that rearrange their interactions upon target RNA binding. Alanine mutation of these residues is shown to select target RNA over an extended complementary sequence beyond guide-target duplex for RNA cleavage, establishing the functional significance of these hotspots. Collectively our findings offer a fundamental understanding of the Cas13a mechanism of action and pave new avenues for the development of highly selective RNA-based cleavage and detection tools.

Bartonella spp. are opportunistic, vectorborne bacteria that can cause disease in both animals and humans. We investigated the molecular occurrence of Bartonella spp. in 634 phlebotomine sand fly specimens, belonging to 44 different sand fly species, sampled during 2017–2021 in north and northeastern Brazil. We detected Bartonella sp. DNA in 8.7% (55/634) of the specimens by using a quantitative real-time PCR targeting the 16S-23S internal transcribed spacer intergenic region. Phylogenetic analysis positioned the Lutzomyia longipalpis sand fly–associated Bartonella gltA gene sequence in the same subclade as Bartonella ancashensis sequences and revealed a Bartonella sp. sequence in a Dampfomyia beltrani sand fly from Mexico. We amplified a bat-associated Bartonella nuoG sequence from a specimen of Nyssomyia antunesi sand fly. Our findings document the presence of Bartonella DNA in sand flies from Brazil, suggesting possible involvement of these insects in the epidemiologic cycle of Bartonella species.

Abstract Human-based modelling and simulation offer an ideal testbed for novel medical therapies to guide experimental and clinical studies. Myocardial infarction (MI) is a common cause of heart failure and mortality, for which novel therapies are urgently needed. Although cell therapy offers promise, electrophysiological heterogeneity raises pro-arrhythmic safety concerns, where underlying complex spatio-temporal dynamics cannot be investigated experimentally. Here, after demonstrating credibility of the modelling and simulation framework, we investigate cell therapy in acute versus chronic MI and the role of cell heterogeneity, scar size and the Purkinje system. Simulations agreed with experimental and clinical recordings from ionic to ECG dynamics in acute and chronic infarction. Following cell delivery, spontaneous beats were facilitated by heterogeneity in cell populations, chronic MI due to tissue depolarisation and slow sinus rhythm. Subsequent re-entrant arrhythmias occurred, in some instances with Purkinje involvement and their susceptibility was enhanced by impaired Purkinje-myocardium coupling, large scars and acute infarction. We conclude that homogeneity in injected ventricular-like cell populations minimises their spontaneous beating, which is enhanced by chronic MI, whereas a healthy Purkinje-myocardium coupling is key to prevent subsequent re-entrant arrhythmias, particularly for large scars.

In this article we present our findings regarding the challenges of offering a massive university's free-of-charge online course. The online course "Introduction to data science (with R)" was offered by one professor at the Federal University of Sao Paulo, Osasco Campus, Brazil, from 11 to 28 of January of 2022, to 680 students from all over the country. This course had the goal of providing educational opportunities for those who otherwise would not be able to afford one. The course followed a problem-based learning approach. In addition to delivering the course content on data science, we wanted to investigate the challenges involved in structuring and delivering the course. Data was collected by means of questionnaires and from the professor's notes. Our findings were as follows: 1) the process of creating an online extension courses can be complex, time-consuming and laborious; 2) handling multiple social media applications and communication tools in order to publicize the extension courses is challenging; 3) the drop-out rate can be high and the completion rate can be low; 4) obtaining the participation of students living in disadvantaged conditions is challenging; and 5) the use of problem-based learning approach facilitated the learning.

As a result of the growing commercial marketplace for teachers' digital data, a new organization that includes educational data brokers has evolved. Educational data brokerage is relatively intangible due to the ease of de-identified data being collected and sold via educational technology. There is an urgent need to expose how the brokerage of educational data relates to the commercial mediation of consent and privacy in educational settings. It is difficult due to a lack of consistent terminology about organizations that buy and sell data. This paper offers an extensive analysis of the social learning platform Edmodo and provides evidence that justifies the term 'educational data broker'. The results aim to provide new terminology to a largely obfuscated process in educational settings and bring to light a concrete example of brokerage activity focusing on teachers' online activity.

This paper focuses on our experiences as higher education workers and the changing work culture that has resulted in the move to online digital labour. The shift to online and remote teaching has had disastrous impacts on academics' ability to both pursue research, and maintain a work-life balance. Examined in this paper is an understanding of how online digital labour has created an ontological shift that has inexorably blurred the boundaries between home and work. We theorize how forms of psychosocial risk in the academy has been normalized in both an intensification of digital labour and in part, an entire sector transformation away from physical campuses. Through a nomenclature of "postdigital presence" we discuss how there has been a fundamental change in how we experience academic work, and narrate how it has (re)formed our working worlds. As future projections, we situate notions of the Slow University and Quiet Quitting as counter hegemonic tactics for policy makers to consider, by reflecting on three "interruptions" around Remote and Isolated work, Job Demands, and Digital Fatigue. We conclude that there is a need to engage in critical questioning around digital labour as an emergent social, anthropological and technological phenomena, not only for improved academic well-being, but also due to the financial risk to institutions of academics being always 'on standby'.