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As we reach the end of 2024, we celebrate an amazing year of science for PLOS Biology and the life sciences more broadly, and thank everyone who continues to support the journal. As we reach the end of 2024, our Editorial celebrates an amazing year of science for PLOS Biology and the life sciences more broadly, and thanks everyone who supports the journal. [ABSTRACT FROM AUTHOR]

Students possess many misconceptions about the nature of science and science practices that hinder robust understanding of science content, diminish interest in science learning, make science appear as an uninteresting career option, and exacerbate distrust of science. With National Science Foundation funding, freely and easily accessible historically accurate short stories have been created that bring science and scientists to life; accurately illustrating the work of scientists and how scientific knowledge is developed and becomes well established. This article presents the project's biology stories, and focuses on the classroom implementation of one story to illustrate mediation strategies that draw students' attention to targeted nature of science and science practices. Research supporting the efficacy of this approach is summarized. [ABSTRACT FROM AUTHOR]

The path from life's origin to the emergence of the eukaryotic cell was long and complex, and as such it is rarely treated in one publication. Here, we offer a sketch of this path, recognizing that there are points of disagreement and that many transitions are still shrouded in mystery. We assume life developed within microchambers of an alkaline hydrothermal vent system. Initial simple reactions were built into more sophisticated reflexively autocatalytic food-generated networks (RAFs), laying the foundation for life's anastomosing metabolism, and eventually for the origin of RNA, which functioned as a genetic repository and as a catalyst (ribozymes). Eventually, protein synthesis developed, leading to life's biology becoming dominated by enzymes and not ribozymes. Subsequent enzymatic innovation included ATP synthase, which generates ATP, fueled by the proton gradient between the alkaline vent flux and the acidic sea. This gradient was later internalized via the evolution of the electron transport chain, a preadaptation for the subsequent emergence of the vent creatures from their microchamber cradles. Differences between bacteria and archaea suggests cellularization evolved at least twice. Later, the bacterial development of oxidative phosphorylation and the archaeal development of proteins to stabilize its DNA laid the foundation for the merger that led to the formation of eukaryotic cells. [ABSTRACT FROM AUTHOR]

Research on the origin of life investigates the transition from abiotic chemistry to the emergence of biology, with the 'RNA world hypothesis' as the leading theory. RNA's dual role in storage and catalysis suggests its importance in this narrative. The discovery of natural ribozymes emphasizes RNA's catalytic capabilities in prebiotic environments, supporting the plausibility of an RNA world and prompting exploration of precellular evolution. Collective autocatalytic sets (CASs) mark a crucial milestone in this transition, fostering complexity through autocatalysis. While modern biology emphasizes sequence-specific polymerases, remnants of CASs persist in primary metabolism highlighting their significance. Autocatalysis, driven by CASs, promotes complexity through mutually interdependent catalytic sets. Yet, the transition from ribonucleotides to complex RNA oligomers remains puzzling. Questions persist about the genesis of the first self-replicating RNA molecule, RNA's stability in prebiotic conditions, and the shift to complex molecular reproduction. This review delves into diverse facets of the RNA world's emergence, addressing critical bottlenecks and scientific advances. Integrating insights from simulation and in vitro evolution research, we illuminate the multistep biogenesis of catalytic RNA from the abiotic world. Through this exploration, we aim to elucidate the journey from the primordial soup to the dawn of life, emphasizing the interplay between chemistry and biology in understanding life's origins. [ABSTRACT FROM AUTHOR]

In the second book of his Ideas for a Phenomenology, Husserl introduces for the first time the notion of Lebenswelt to describe what until then was the original ground of the genesis of sense. In his Logical Investigations, when describing language games, Wittgenstein works with the idea that these are forms of life (Lebensformen). By no means exhaustive, this note seeks to briefly discuss what is meant by the term life in both cases, to show that the strict correlation of bios with logos does not exactly include a biological understanding of the concept. The first part will discuss the problem in the second Wittgenstein; the second will be devoted to Husserl's fundamental ontology. [ABSTRACT FROM AUTHOR]

Menopause is the cessation of ovarian function, with loss of reproductive hormone production and irreversible loss of fertility. It is a natural part of reproductive aging. The physiology of the menopause is complex and incompletely understood. Globally, menopause occurs around the age of 49 years, with geographic and ethnic variation. The hormonal changes of the menopause transition may result in both symptoms and long-term systemic effects, predominantly adverse effects on cardiometabolic and musculoskeletal health. The most effective treatment for bothersome menopausal symptoms is evidence-based, menopausal hormone therapy (MHT), which reduces bone loss and may have cardiometabolic benefits. Evidence-based non-hormonal interventions are also available for symptom relief. Treatment should be individualized with shared decision-making. Most MHT regimens are not regulator approved for perimenopausal women. Studies that include perimenopausal women are needed to determine the efficacy and safety of treatment options. Further research is crucial to improve menopause care, along with research to guide policy and clinical practice. Menopause is a natural part of reproductive aging affecting roughly half the world's population. This review summarizes the biology and life consequences of menopause, the role of supportive care, menopause-specific therapeutic options, and future research directions that are needed to achieve better menopause care. [ABSTRACT FROM AUTHOR]

This review examines the potential of Project-Based Learning (PjBL) to enhance students' life skills in the field of biology, and analyzes the challenges that may hinder its implementation. Using a Systematic Literature Network Analysis (SLNA), which combines Bibliometrics Analysis (BA) and Systematic Literature Review (SLR), this study analyzed articles from SCOPUS that met specific criteria. The findings reveal that PjBL is associated with e-learning and blended learning, and that the majority of articles on PjBL were published in 2020, particularly in the Journal of Microbiology & Biology Education. Additionally, this SLNA highlights the contributions of these articles to the developing of various life skills in biology learning. By identifying key trends and insights from existing literature, this study sheds light on the potential of PjBL to enhance students' biology education and their ability to apply it in their daily lives. [ABSTRACT FROM AUTHOR]

One of life's most striking characteristics is its mental dimension, one whose very existence within a material system has long been a deep scientific mystery. Given the current scientific view that life emerged from non-life, how was it possible for 'dead' matter to have taken on mental capabilities? In this Perspective we describe the existence of a recently discovered non-equilibrium state of matter, an energized dynamic kinetic state, and demonstrate how particular chemical systems once activated into that kinetic state could manifest rudimentary cognitive behavior. Thus, contrary to a common view that biology is not reducible to physics and chemistry, recent findings in both chemistry and biology suggest that life's mental state is an outcome of its physical state, and therefore may be explicable in physical/chemical terms. Such understanding offers added insight into the physico-chemical process by which life was able to emerge from non-life and the perennial 'what is life?' question. Most remarkably, it appears that Darwin, through his deep understanding of the evolutionary process, already sensed the existence of a connection between life's physical and mental states. [ABSTRACT FROM AUTHOR]

Modernfish represent over 400 million years of evolutionary processes that, in many cases, resulted in selection for phenotypes with particular performance advantages. While this certainly occurred without a trajectory for optimization, it cannot be denied that some morphologies allow organisms to be more effective than others at tasks like evading predation, securing food, and ultimately passing on their genes. In this way, evolution generates a series of iterative prototypes with varying but measurable success in accomplishing objectives. Therefore, careful analysis of fundamental properties underlying biological phenomena allows us to fast-track the development of bioinspired technologies aiming to accomplish similar objectives. At the same time, bioinspired designs can be a way to explore evolutionary processes, by better understanding the performance space within which a given morphology operates. Through strong interdisciplinary collaborations, we can develop novel bioinspired technologies that not only excel as robotic devices but also teach us something about biology and the rules of life in the process. [ABSTRACT FROM AUTHOR]

Developmental times, reproduction rate and life table parameters of Tetranychus urticae Koch of two ornaments plants Marshmallow and Salvia treated with four doses of gamma radiation 15, 25, 35 and 45 Kilo rad was studied under laboratory conditions at 25 ± 2°C, 65% RH. The results indicate that applied of gamma radiation had a significant effect on the duration of male and female feeding on salvia and Marshmallow leaves irrigated. The life cycle and generation period of irradiated females increased with increasing doses of gamma radiation and were significantly higher than the control. The female oviposition and longevity periods of T. urticae significantly increased with an increased dose of gamma radiation. The mean fecundity and daily rate significantly decreased with increasing doses of gamma radiation on salvia and marshmallows. A significant positive correlation was found between all immature stages, generation, and oviposition periods and the dose of gamma radiation. The Intrinsic rate of increase (rm) and net reproductive rate (R0) of T. urticae was the lowest at 45 Kilo rad (0.148 female/female/day and 20.59 female/female) and the highest value was found at control (0.256 female/female/day and 44.70 female/female), respectively on salvia leaves. The radiation of salvia and Marshmallow seeds reduced the fecundity of T. urticae females and prolonged the generation time than in control. [ABSTRACT FROM AUTHOR]

The mango red spider mite, Oligonychus mangiferus, is a dangerous pest of mango that causes an indirect reduction in the production and quality of mango fruits. Since there is an urgent need to control O. mangiferus, searching for native phytoseiids that can prey on O. mangiferus may provide promising results in the biological control of this mite pest. In this study, biological and life table parameters of the predatory mites Cydnoseius negevi, Neoseiulus barkeri, Paraseiulus talbii, and Typhlodromus athiasae were determined when fed on O. mangiferus under laboratory conditions. Cydnoseius negevi, N. barkeri, and T. athiasae were successfully fed and developed on O. mangiferus, while P. talbii failed to develop on O. mangiferus. The pre-adult duration did not differ significantly among the three phytoseiids. The longest female longevity was 40.28 days for N. barkeri, while the shortest was 26.04 days for C. negevi. The lowest daily fecundity was observed in N. barkeri females, whereas the highest was oviposited by C. negevi and T. athiasae. Statistically, Typhlodromus athiasae had the maximum intrinsic rate of increase (r) and finite rate of increase (λ), followed by N. barkeri and C. negevi. The shortest mean generation time (T) and the lowest net reproductive rate (R0) were reported for C. negevi. In conclusion, C. negevi, N. barkeri, and T. athiasae successfully fed, developed and sustained oviposition on O. mangiferus. Therefore, they could be considered as important biological control agents of O. mangiferus. [ABSTRACT FROM AUTHOR]

The seeds of most medicinal plants have a variety of dormancy. Therefore, it is necessary to know the effective methods of breaking the seed dormancy for their production and cultivation. In this study, to determine the best method of breaking dormancy and increasing the germination percentage of tattoo seeds, various factors have been investigated. Different treatments, scratching with sandpaper, embryo culture, GA treatment (100, 150 and 200 PPM) and sulfuric acid treatment (50, 75 and 100%) with filter paper or on MS medium containing BAP (0.5, 1 and 1.5 mg/l) was applied with untreated samples (control). Embryo culture was performed only on MS medium containing BAP hormone. The analysis of variance showed that all interactions with the studied treatments were significantly different in terms of germination percentage, fresh and dry weight of roots and stems (P <0.01). It was observed that the use of benzyl aminopurine (1.5 mg/l) with gibberellic acid (200 ppm) increased the seed germination percentage compared to the control. The use of benzylaminopurine (1.5 mg/l) and sulfuric acid (50%) significantly increased seed germination compared to the control. It was concluded that the effect of GA with BAP on seed germination was greater than sulfuric acid with BAP. [ABSTRACT FROM AUTHOR]

The genus Porphyra sensu lato (Bangiaceae, Rhodophyta), an important seaweed grown in aquaculture, is the most genetically diverse group of the Class Bangiophyceae, but has poorly understood genetic variability linked to complex evolutionary processes. Genetic studies in the last decades have largely focused on resolving gene phylogenies; however, there is little information on historical population biogeography, structure and gene flow in the Bangiaceae, probably due to their cryptic nature, chimerism and polyploidy, which render analyses challenging. This study aims to understand biogeographic population structure in the two abundant Porphyra species in the Northeast Atlantic: Porphyra dioica (a dioecious annual) and Porphyra linearis (protandrous hermaphroditic winter annual), occupying distinct niches (seasonality and position on the shore). Here, we present a large-scale biogeographic genetic analysis across their distribution in the Northeast Atlantic, using 10 microsatellites and cpDNA as genetic markers and integrating chimerism and polyploidy, including simulations considering alleles derived from different ploidy levels and/or from different genotypes within the chimeric blade. For P. linearis , both markers revealed strong genetic differentiation of north-central eastern Atlantic populations (from Iceland to the Basque region of Northeast Iberia) vs. southern populations (Galicia in Northwest Iberia, and Portugal), with higher genetic diversity in the south vs. a northern homogenous low diversity. For. P. dioica , microsatellite analyses also revealed two genetic regions, but with weaker differentiation, and cpDNA revealed little structure with all the haplotypes mixed across its distribution. The southern cluster in P. linearis also included introgressed individuals with cpDNA from P. dioica and a winter form of P. dioica occurred spatially intermixed with P. linearis. This third entity had a similar morphology and seasonality as P. linearis but genomes (either nuclear or chloroplast) from P. dioica. We hypothesize a northward colonization from southern Europe (where the ancestral populations reside and host most of the gene pool of these species). In P. linearis recently established populations colonized the north resulting in homogeneous low diversity, whereas for P. dioica the signature of this colonization is not as obvious due to hypothetical higher gene flow among populations, possibly linked to its reproductive biology and annual life history. [ABSTRACT FROM AUTHOR]

The proper development and patterning of organs rely on concerted signaling events emanating from intracellular and extracellular molecular and biophysical cues. The ability to model and understand how these microenvironmental factors contribute to cell fate decisions and physiological processes is crucial for uncovering the biology and mechanisms of life. Recent advances in microfluidic systems have provided novel tools and strategies for studying aspects of human tissue and organ development in ways that have previously been challenging to explore ex vivo. Here, we discuss how microfluidic systems and organs-on-chips provide new ways to understand how extracellular signals affect cell differentiation, how cells interact with each other, and how different tissues and organs are formed for specialized functions.We also highlight key advancements in the field that are contributing to a broad understanding of human embryogenesis, organogenesis and physiology. We conclude by summarizing the key advantages of using dynamic microfluidic or microphysiological platforms to study intricate developmental processes that cannot be accurately modeled by using traditional tissue culture vessels. We also suggest some exciting prospects and potential future applications of these emerging technologies. [ABSTRACT FROM AUTHOR]

Clarina syriaca (Lederer, 1855) was known from Cyprus by a single adult specimen collected in 1950. Recently, an adult and larva have been found, proving the existence of a breeding population. Clarina syriaca is thus confirmed as resident in Cyprus, as a relict population inhabiting riparian gallery forests, which act as isolated refugia surrounded by drier pine woodland or cultivated land. Information is provided on the early life history stages of C. syriaca, with further notes on its taxonomic status, biology, ecology, and host plants. [ABSTRACT FROM AUTHOR]

The predatory mite Proprioseiopsis lindquisti completed its development and reproduced successfully on three eriophyid mites, Aculops lycopersici, Aceria mangiferae, and Aculus fockeui, under laboratory conditions. Feeding on A. mangiferae and A. fockeui resulted in short developmental and long oviposition periods and was a suitable food for predator oviposition as it resulted in high fecundity, gross and net reproductive rates. Feeding on A. lycopersici elongated the developmental period and was less favorable for the predator as it gave the lowest rate of oviposition and net reproductive rates. Higher intrinsic rates of increase, and finite rates of increase for P. lindquisti were recorded on A. mangiferae while A. lycopersici and A. fockeui produced lower values. [ABSTRACT FROM AUTHOR]

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Breathing Life into Biology is a brave attempt to do science while wearing its values on its sleeves. It is written under the commitment that life is intrinsically valuable, and its value has to be taken seriously in doing biology. Stewart defends a conception of life in which every living organism has a subjective point of view from which it makes sense of the world. Under this conception and the commitment that life is valuable in itself, the book presents the story of life from its origin and our history as humankind. However, the book is more successful in presenting the former than the latter. Yet Stewart's conception of enaction opens the possibility for cognitive science and his conception of what makes us human enables us to embrace the histories and the forms of life of those who have been systematically silenced. [ABSTRACT FROM AUTHOR]

This study reports and problematizes three findings from multiple texts on the science-technology-society triad that refer to the knowledge and practices of biotechnology and synthetic biology, two fields that aim to optimize what is alive and life. Said findings reveal the modes of operation of biology and biotechnology as life technologies. For that purpose, this paper used the methodological notions of government and counter-conducts taken from Foucault's toolbox because they focus on finding solutions that maximize human performance by accepting practices related to the transformation of vitality. The first finding questions the applications of biotechnology; the second one reveals the positioning of synthetic biology in the industrial sector; and the third one, related to bioart, problematizes the implications of the government of that what is alive and life from an economic perspective. Therefore, this article stimulates a reflection on biotechnology and synthetic biology as part of our daily life, which encourages us to be concerned about the acceptance of well-established practices regarding human and environmental wellbeing, question the truths that constitute us, and express ourselves based on personal choices that reveal our ethical position. [ABSTRACT FROM AUTHOR]

Arachnida evolved different reproductive strategies in the terrestrial habitats. Knowledge of the morphology of reproductive systems varies depending on the group, and for Opiliones only a few studies exists addressing this topic. Here, we describe the morphology of the male reproductive tract and the spermatozoon of the harvestman Mischonyx cuspidatus (Roewer, 1913). In this species, males have a single testis, a pair of deferent ducts, a seminal vesicle, a propelling organ and a penis. The lumen of the folded seminal vesicle and testis follicles are filled with spermatozoa, suggesting a storage of sperm related to a possible reproductive strategy involving multiple matings. The spermatozoa are aflagellate and ca. 6.5 µm in length. This study sheds light on the knowledge of the harvestman's reproductive biology and life strategy, which can be used in future studies involving Opiliones behavior and systematics. [ABSTRACT FROM AUTHOR]

The document titled "The First Eleven (2013-2023) of Life: The Excitement of Biology" is an editorial by Jorge A. Santiago-Blay, the Editor-in-Chief of the journal. The editorial discusses the major developments of the journal, highlighting the challenges faced due to the COVID-19 pandemic and professional demands. Santiago-Blay expresses gratitude to authors, reviewers, guest editors, and supporters who have contributed to the success of the journal. The editorial emphasizes the mission of fostering innovation and accessibility in scientific research, while also acknowledging the support received from various individuals and organizations. [Extracted from the article]

We study the problem of visualizing phylogenetic networks, which are extensions of the Tree of Life in biology. We use a space filling visualization method, called DAGmaps, in order to obtain clear visualizations using limited space. In this paper, we first show that the general problem of drawing galled networks as DAGmaps is NP-complete. Next, we restrict our attention to galled trees and planar galled networks and present linear time algorithms for visualizing them as DAGmaps. Finally, we explore whether these graphs can be visualized using One-Dimensional DAGmaps. [ABSTRACT FROM AUTHOR]

One of the central aims of synthetic biology (SB) is to better understand the mechanisms of life by trying to develop and synthesize new forms and perhaps modes of life. While the question of what is life has occupied mankind for centuries, there is a lack of empirical research examining the basic concepts of life scientists within SB themselves refer to and build on. In order to gain insights into these fundamental concepts, we conducted a qualitative interview study with scientists working in the field of SB. The aim was to gain a better understanding of the underlying understandings, principles, and characteristics of (synthetic) life on the one hand, and the entangled consequences for the conducted experiments and studies as well as the pursued scientific approaches. We identified four primarily underlying basic concepts of life which serve as a fundamental framework for current and further scientific research within SB and have implications for research questions, approaches and aims as well as for the evaluation of scientific results. [ABSTRACT FROM AUTHOR]

The quality of the important host plants affects the survival, development, and reproduction of the tospotd spider mite, Tetranychus urticae Koch. The biology and life table parameters of T. urticae, on four cultivars of common Regular and Sweet pea and Polesta & G6 bean, were examined under laboratory conditions of 27 ± 1 °C, 60-80% R.H. and photoperiod 16L: 8D h. Both males and females of T. urticae successfully developed from egg to adult on different host plants. Results revealed that the survival rate varied from 53% on Regular pea to 99% on G6 bean cultivars. The developmental time from egg to adult was significantly influenced among the tested host plant cultivars and ranged from 9.75 days on G6 bean to 20.42 days on Regular pea (p = 0.00). Female longevity was significantly longer on Regular and Sweet pea than on Polesta and G6 bean. The highest fecundity per female was recorded on G6 bean, but the lowest was on Regular pea cultivars. Consequently, population growth parameters were also significantly influenced by different host plants. The net reproductive rate (R0), the intrinsic rate of natural increase (r), and the finite rate of increase (λ) of T. urticae were significantly higher on G6 bean than the other three cultivars. Also, the longest mean generation time (T) and doubling time (DT) were noted on Regular pea, but the shortest value on G6 and Polesta bean cultivars. Obtained results based on the intrinsic rate of natural increase revealed that G6 and Polesta bean were more suitable than the two pea cultivars as hosts for T. urticae. Therefore, the lower population growth rate of the T. urticae could be the result of antibiotic resistance in the cultivars Regular and Sweet pea. [ABSTRACT FROM AUTHOR]

Cricotopus lebetis Sublette (Diptera: Chironomidae) is an aquatic insect adventive in Florida. Evidence from previous studies suggest the insect may have value as an augmentative biological control agent for hydrilla, Hydrilla verticillata (L.f.) Royle (Hydrocharitaceae), but there are gaps in knowledge of the biology and life history traits. To increase understanding of this insect, this study was comprised of 3 experiments. In the first experiment, we investigated the productivity and survival rate of C. lebetis across 6 generations by analyzing our colony data. Then the effect of intraspecific competition on the rates of pupal and adult eclosion was studied by monitoring hydrilla tips in test tubes with varying numbers of larvae. Finally, the level of hydrilla stem tip damage caused by a C. lebetis larva was determined by monitoring tip damage following feeding of a known number of larvae on a standardized number of hydrilla tips. The first experiment revealed the average survival rate of C. lebetis from egg to adult was 16.4%. Approximately a third of the females (30.2%) oviposited. The egg masses had an average of 154.5 eggs per egg mass and an 83.7% fertility rate. Investigation of intraspecific competition revealed pupation and adult eclosion was highest with 1 C. lebetis larva per hydrilla stem tip. Evaluation of the impact of C. lebetis larvae feeding on hydrilla showed stem tips in treatments with C. lebetis larvae experienced 38% higher damage compared to stem tips in control treatments. Overall, this study provided valuable information useful in improving the mass rearing of C. lebetis and predicting the damage caused by C. lebetis. For example, for efficient mass rearing, an average of 1 larva per hydrilla tip should be maintained with the remainder of eggs being used for augmentative releases. [ABSTRACT FROM AUTHOR]

The guava cottony scale, Capulinia linarosae (Hemiptera: Eriococcidae) is an important pest of guava, Psidium guajava, in Venezuela and northern Colombia. Metaphycus marensis (Hymenoptera: Encyrtidae) is a new primary parasitoid species recently described associated with this pest. Studies were conducted on oogenesis, life cycle, survival, daily fecundity and life table parameters of Metaphycus marensis Chirinos & Kondo (Hymenoptera: Encyrtidae): intrinsic rate of natural increase (rm), generation time (T) and net reproductive rate (Ro). Females of M. marensis are synovigenic and this parasitoid goes through four larval instars and completes its life cycle in about 12.7 days. Survival was of type I, where mortality was initially detected by encapsulation of eggs and larvae. Metaphycus marensis was able to multiply its population 28.7 times (Ro) with rm of 0.242 in 13.9 days (T). The short generation time of the parasitoid in relation to its eriococcid host could represent a desirable attribute as a natural enemy. However, the low fecundity and the encapsulation by the host must be analyzed through field experiments in order to evaluate its effectiveness as a biological control agent for C. linarosae. [ABSTRACT FROM AUTHOR]

The black inch looper, Hyposidra talaca is considered as a major pest in tea in northern part of West Bengal and North East India. Among the natural enemy reported, Cotesia ruficrus is considered as one of the most gregarious endo-parasitoid wasps. In order to assess the potential of this natural enemy, a study on the biological parameters of C. ruficrus was evaluated on the different developmental stages (second, third and fourth instars) of the host larvae, H. talaca. The results indicated that, the mean duration of larval development was 12.0 ± 0.32, 11.0 ± 0.45 and 9.2±0.37 days in second, third and fourth instar host larvae respectively. The pupal period of C. ruficrus was found to be significantly different among the different larval stages of H. talaca. The successful parasitism of C. ruficrus and the number of cocoon formation of the parasitic wasp was reliant on the stage, body size and the physiological conditions of host larvae that it parasitizes. A maximum of 65.2±1.85 cocoons were formed when the fourth instar host larvae parasitized, followed by 27.2±3.04 in the third instar and 4.6±0.68 in the second instar host larvae. The number of females and males hatched out from each clutch was compared to the different host stages. [ABSTRACT FROM AUTHOR]

This study examines the initial integration of engineering design in an introductory preservice elementary biology content course using a life science design task focused on composting. The task, informed by a three-dimensional learning approach, required preservice teachers to research and model the process and use of composting to help the citizens of Puerto Rico recover after the destruction caused by Hurricanes Irma and Maria. Data were gathered using concept assessments, design task assignments, and critical course reflections. Findings indicated that students made significant science learning gains, demonstrated knowledge about modeling, and exhibited an informed perspective of the design task as personally relevant. By exploring the initial implementation of the compost design experience, the authors aim to make visible the potential benefits of introducing an engineering design task informed by a three-dimensional learning approach on student science learning and relevancy. [ABSTRACT FROM AUTHOR]

A definitive endodermal cell lineage is a prerequisite for the efficient generation of mature endoderm derivatives that give rise to organs, such as the pancreas and liver. We previously reported that the induction of mesenchymal definitive endoderm cells depends on autocrine TGF-β signaling and that pharmacological blockage of TGF-β signaling by Repsox disrupts endoderm specification. The definitive endoderm arises from a primitive streak, which depends largely on TGF-β signaling. If the TGF-β pathway is blocked by Repsox, cell fate after the primitive streak induction is so-far unknown. We report here, that an induced primitive streak cell-population contained many T/SOX2 co-expressing cells, and subsequent inhibition of TGF-β signaling by Repsox promoted neuroectodermal cell fate, which was characterized using single-cell qPCR analysis and immunostaining. The process of epithelial-to-mesenchymal transition, which is inherent to the process of definitive endoderm differentiation, was also disrupted upon Repsox treatment. Our findings may provide a new approach to produce neural progenitors. [ABSTRACT FROM AUTHOR]