Metabolism And The Rise Of Fungus Cultivation By Ants

Most ant colonies are comprised of workers that cooperate to harvest resources and feed developing larvae. Around 50 million years ago (MYA), ants of the attine lineage adopted an alternative strategy, harvesting resources used as compost to produce fungal gardens. While fungus cultivation is considered a major breakthrough in ant evolution, the associated ecological consequences remain poorly understood. Here, we compare the energetics of attine colony-farms and ancestral hunter-gatherer colonies using metabolic scaling principles within a phylogenetic context. We find two major energetic transitions. First, the earliest lower-attine farmers transitioned to lower mass-specific metabolic rates while shifting significant fractions of biomass from ant tissue to fungus gardens. Second, a transition 20 MYA to specialized cultivars in the higher-attine clade was associated with increased colony metabolism (without changes in garden fungal content) and with metabolic scaling nearly identical to hypometry observed in hunter-gatherer ants, although only the hunter-gatherer slope was distinguishable from isometry. Based on these evolutionary transitions, we propose that shifting living-tissue storage from ants to fungal mutualists provided energetic storage advantages contributing to attine diversification and outline critical assumptions that, when tested, will help link metabolism, farming efficiency, and colony fitness.Integrative Biolog

CRL1-FBXO11 Promotes Cdt2 Ubiquitylation and Degradation and Regulates Pr-Set7/Set8-Mediated Cellular Migration

The Cul4-Cdt2 (CRL4(Cdt2)) E3 ubiquitin ligase is a master regulator of cell-cycle progression and genome stability. Despite its central role in the degradation of many cell-cycle regulators, e.g., Cdt1, p21, and Pr-Set7/Set8, little is known about the regulation of its activity. We report that Cdt2 is autoubiquitylated by the CRL4A E3 ubiquitin ligase. Cdt2 is additionally polyubiquitylated and degraded by Cul1-FBXO11 (CRL1(FBXO11)). CRL1(FBXO11)-mediated degradation of Cdt2 stabilizes p21 and Set8, and this is important during the response to TGF-β, with the Set8 induction being important for turning off the activation of Smad2. The migration of epithelial cells is also stimulated by CRL1(FBXO11)-mediated downregulation of Cdt2 and the consequent stabilization of Set8. This is an interesting example of cross-regulation between specific Cullin 4 and Cullin 1 E3 ubiquitin ligases and highlights the role of ubiquitylation in regulating cellular responses to TGF-β and the migration of epithelial cells.Fil: Abbas, Tarek. University of Virginia; Estados UnidosFil: Mueller, Adam C.. University of Virginia; Estados UnidosFil: Shibata, Etsuko. University of Virginia; Estados UnidosFil: Keaton, Mignon. University of Virginia; Estados UnidosFil: Rossi, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires; ArgentinaFil: Dutta, Anindya. University of Virginia; Estados Unido

Evaluation of a Terrain Attribute Model for Locating Areas Suitable for Grassed Waterways in Agricultural Settings

Grassed waterways placed in high water flow zones substantially reduce erosion in agricultural fields. A recent study proposed a statistical model for waterway planning for a farm in the Outer Bluegrass physiographic region of Kentucky. The logistic regression model identified where channel erosion was likely to occur based on elevation-derived terrain attributes. The objective of this study was to test their model in fields located in the Western Coal Fields physiographic region where soils differ substantially. Model predictions corresponded well with known areas of concentrated flow (i.e., maps of existing waterways, surface drains, and observations of erosion). The geographic inference space of the waterway planning model was large. Overall, the results indicated that the geographic inference space of the waterway planning model was larger than expected. This analysis suggested that the proposed modeling procedure was robust and has the potential to be an effective tool to help conservationists identify areas where waterways should be located on some Kentucky landscapes

Reactive Laser Synthesis of Ultra-high-temperature Ceramics HfC, ZrC, TiC, HfN, ZrN, and TiN for Additive Manufacturing

Ultra-high-temperature ceramics (UHTCs) are optimal structural materials for applications that require extreme temperature resilience, resistance to chemically aggressive environments, wear, and mechanical stress. Processing UHTCs with laser-based additive manufacturing (AM) has not been fully realized due to a variety of obstacles. In this work, selective laser reaction sintering (SLRS) techniques were investigated for the production of near net-shape UHTC ceramics such as HfC, ZrC, TiC, HfN, ZrN, and TiN. Group IV transition metal and metal oxide precursor materials were chemically converted and reaction-bonded into layers of UHTCs using single-step selective laser processing in CH4 or NH3 gas that might be compatible with prevailing powder bed fusion techniques. Conversion of either metals (Hf, Zr and Ti) or metal oxides (HfO2, ZrO2, and TiO2) particles was first investigated to examine reaction mechanisms and volume changes associated with SLRS of single-component precursor systems. SLRS processing of metal or metal oxide alone produced near stoichiometric UHTC phases with yields up to 100 wt% total for carbides and nitrides. However, for single component precursors, gas-solid reactivity induced volumetric changes resulted in residual stresses and cracking in the product layer. To mitigate conversion-induced stresses, composite metal/metal oxide precursors were employed to compensate for the volume changes of either the metal (which expands during conversion) or the metal oxide precursor (which contracts).Comment: 58 pages, 17 figure

Fluctuating selection models and Mcdonald-Kreitman type analyses

It is likely that the strength of selection acting upon a mutation varies through time due to changes in the environment. However, most population genetic theory assumes that the strength of selection remains constant. Here we investigate the consequences of fluctuating selection pressures on the quantification of adaptive evolution using McDonald-Kreitman (MK) style approaches. In agreement with previous work, we show that fluctuating selection can generate evidence of adaptive evolution even when the expected strength of selection on a mutation is zero. However, we also find that the mutations, which contribute to both polymorphism and divergence tend, on average, to be positively selected during their lifetime, under fluctuating selection models. This is because mutations that fluctuate, by chance, to positive selected values, tend to reach higher frequencies in the population than those that fluctuate towards negative values. Hence the evidence of positive adaptive evolution detected under a fluctuating selection model by MK type approaches is genuine since fixed mutations tend to be advantageous on average during their lifetime. Never-the-less we show that methods tend to underestimate the rate of adaptive evolution when selection fluctuates

WiSer: A Highly Available HTAP DBMS for IoT Applications

In a classic transactional distributed database management system (DBMS), write transactions invariably synchronize with a coordinator before final commitment. While enforcing serializability, this model has long been criticized for not satisfying the applications' availability requirements. When entering the era of Internet of Things (IoT), this problem has become more severe, as an increasing number of applications call for the capability of hybrid transactional and analytical processing (HTAP), where aggregation constraints need to be enforced as part of transactions. Current systems work around this by creating escrows, allowing occasional overshoots of constraints, which are handled via compensating application logic. The WiSer DBMS targets consistency with availability, by splitting the database commit into two steps. First, a PROMISE step that corresponds to what humans are used to as commitment, and runs without talking to a coordinator. Second, a SERIALIZE step, that fixes transactions' positions in the serializable order, via a consensus procedure. We achieve this split via a novel data representation that embeds read-sets into transaction deltas, and serialization sequence numbers into table rows. WiSer does no sharding (all nodes can run transactions that modify the entire database), and yet enforces aggregation constraints. Both readwrite conflicts and aggregation constraint violations are resolved lazily in the serialized data. WiSer also covers node joins and departures as database tables, thus simplifying correctness and failure handling. We present the design of WiSer as well as experiments suggesting this approach has promise

Mirror Position Determination for the Alignment of Cherenkov Telescopes

Imaging Atmospheric Cherenkov Telescopes (IACTs) need imaging optics with large apertures to map the faint Cherenkov light emitted in extensive air showers onto their image sensors. Segmented reflectors fulfill these needs using mass produced and light weight mirror facets. However, as the overall image is the sum of the individual mirror facet images, alignment is important. Here we present a method to determine the mirror facet positions on a segmented reflector in a very direct way. Our method reconstructs the mirror facet positions from photographs and a laser distance meter measurement which goes from the center of the image sensor plane to the center of each mirror facet. We use our method to both align the mirror facet positions and to feed the measured positions into our IACT simulation. We demonstrate our implementation on the 4 m First Geiger-mode Avalanche Cherenkov Telescope (FACT).Comment: 11 figures, small ray tracing performance simulation, and implementation demonstratio

16th Annual Pancreatic Cancer and Related Diseases Patient Symposium

On November 13, 2021, Charles J. Yeo, MD, FACS, and the multidisciplinary team of clinicians and scientists hosted the 16th Annual Pancreatic Cancer & Related Diseases Symposium. The video of the event is available here: vimeo.com/646517712/36786afe68. View our Pancreatic Cancer Program 2021 Update to learn more about Dr. Yeo and the team’s great work! PROGRAM Welcome and Program OverviewCharles J. Yeo, MD, FACSSamuel D. Gross Professor and Chair of Surgery Advances in FT in Treating Pancreatic CancerAdam Mueller, MD, PhDInstructor, Radiation Oncology KRAS Mutation Allele Frequency Impacts Prognosis in Pancreatic Ductal Adenocarcinoma Using Next-Generation SequencingHarish Lavu, MD, FACSProfessor of Surgery COVID-19 Pandemic and the JPTR: Results of the 2022-2021 Annual SurveyTheresa P. Yeo, PhD, AOCHP, ACNP-BC, FAANPProfessor, Jefferson College of Nursing Jefferson Pancreatic Cancer Research Institute UpdateAvinoam Nevler, MDAssistant Professor Pancreatic Cancer: Progress in Systemic TherapiesDaniel Lin, MD, MScAssistant Professor of Medical Oncology Pancreatic Neuroendocrine Tumors (PNETs): Overview and TreatmentWilbur B. Bowne, MDProfessor of Biochemistry and Molecular Biology Questions & Answers Survivor Tribute Photo & Survivor Testimonia

Children’s first experience of taking anabolic-androgenic steroids can occur before their 10th birthday: a systematic review identifying 9 factors that predict doping among young people

Taking performance-enhancing drugs (PEDs) can cause serious and irreversible health consequences, which can ultimately lead to premature death. Some young people may take PEDs without fully understanding the ramifications of their actions or based on the advice from others. The purpose of this systematic review was to identify the main factors that predicted doping among young people. The literature was systematically reviewed using search engines, manually searching specialist journals, and pearl growing. Fifty-two studies, which included 187,288 young people aged between 10 and 21 years of age, 883 parents of adolescent athletes, and 11 adult coaches, who were interviewed regarding young athletes, were included in this review. Nine factors predicted doping among young people: gender; age; sports participation; sport type; psychological variables; entourage; ethnicity; nutritional supplements’ and health harming behaviors. In regards to psychological variables, 22 different constructs were associated with doping among young people. Some psychological constructs were negatively associated with doping (e.g., self-esteem, resisting social pressure, and perfectionist strivings), whereas other were positively associated with doping (e.g., suicide risk, anticipated regret, and aggression). Policy makers and National Anti-Doping Organisations could use these findings to help identify athletes who are more at risk of doping and then expose these individuals to anti-doping education. Based on the current findings, it also appears that education programs should commence at the onset of adolescence or even late childhood, due to the young age in which some individuals start doping