Fundamental Constituents Research Articles

Human Influence On Global Climate: Legal Protection For Sustenance Of Life On Earth

Changes in solar irradiance may have affected global climate, the importance of the climate change issue stems from the impact of changes in climate on human and natural systems. The two most well-known consequences of climate change are an increase in global-mean temperature and a rise in sea level. The primary components of sea-level rise are thermal expansion and the melting of small glaciers. However, there are other changes in climate could be as important, or even so, than changes in the mean climate state. These include changes in precipitation and climate variability, particularly changes in the intensity and/or severity of extreme events such as droughts, floods, or tropical storms.
 Physics deals with the structure of matter and how the fundamental constituents of the universe interact. The impact of humans on the environment revolves around the need of physical science to understand how human beings change a natural system, an understanding of global warming and the associated climate change. Hence, physicists will approach numerous troubles from more than one direction. Physicists had to constantly keep attentive to changes, to visualize one factor going on in nature, to discover new phenomena and to document it in order that they will describe it later. Thus studying physics strengthens quantitative reasoning and problem solving skills. The environment is the natural world but with toxic chemicals, spacecraft, and nuclear bombs, humans seem to be moving further and further away from what could be called 'natural' every day. As physics strengthens quantitative reasoning and problem-solving skills, it should be dealt transdisciplinary with Law will surely helps in reducing human influence on global climate and render legal protection for sustenance of life on earth. Hence the paper concentrates on the importance of application of physical principles to environmental problems and the proactive role played by judiciary in different countries in protecting life on earth by adopting policies relating to climate change, enhancing ethical principles by setting regulations and standards for operating industries.

Fufang Shenhua tablet inhibits renal fibrosis by inhibiting PI3K/AKT

BackgroundFufang Shenhua tablet (SHT), a traditional Chinese medicine compound, has been utilized in the clinical management of chronic kidney disease (CKD) for a long time. Nevertheless, the fundamental active constituents and potential mechanism of action remain unclear. Thus, the objective of this study was to investigate the renoprotective effect of SHT on residual renal tissue in CKD model rats and to explore its primary efficacious components and their underlying mechanism. MethodsAfter a 12-week period of SHT treatment through gavage in a 5/6 nephrectomized animal model of CKD, we evaluated the body weight, renal function, and renal pathological changes. Furthermore, the expression levels of fibronectin (FN), collagen I (COL-1), α-smooth muscle actin (α-SMA), and vimentin in renal tissues were assessed. In addition, network pharmacology analysis and molecular docking were utilized to predict the primary active components, potential therapeutic targets, and intervention pathways through which SHT could potentially exert its anti-kidney fibrosis effects. Subsequently, these predictions were validated in renal tissues of rats with CKD and in transforming growth factor β1 (TGF-β1)-induced HK-2 cells. ResultsSHT significantly improved renal function and reduced renal pathological damage and fibrosis in CKD model rats. Network pharmacological analysis identified 62 active components in SHT, with quercetin ranked first, and 105 protein targets shared by SHT and CKD. Based on the protein‒protein interaction network (PPI) and the SHT-CKD-pathway network, AKT1, MYC, IL2, and VEGFA were identified as key targets. Furthermore, GO and KEGG pathway enrichment analyses indicated that the renoprotective effect of SHT on CKD was closely associated with the PI3K/AKT signaling pathway. Molecular docking results demonstrated that the main active components of SHT had a strong binding affinity to the hub genes. During experimental validation, SHT hindered the activity of the PI3K/AKT signaling pathway in the renal tissue of CKD model rats. Furthermore, activation of the PI3K/AKT signaling pathway was correlated with a modified fibrotic phenotype in rats with 5/6 nephrectomy-induced CKD and TGF-β1-induced HK-2 cells. Conversely, SHT and quercetin curtailed the activation of the PI3K/AKT signaling pathway and inhibited the formation of renal fibrosis, thus indicating that the PI3K/AKT signaling pathway is the basis of the antifibrotic effects of SHT. Ultimately, administration of the PI3K/AKT agonist 740Y-P counteracted the fibrotic phenotype of TGF-β1-induced HK-2 cells induced by SHT. ConclusionsIn this investigation, we employed a fusion of systems pharmacology and in vivo and in vitro experiments to elucidate the mechanism of SHT's antifibrotic properties via obstruction of the PI3K/AKT signaling pathway. Additionally, we surmised that AKT may be the principal target of SHT for the management of CKD and that quercetin may be its efficacious component. We have thus identified SHT as a promising drug for the amelioration of renal fibrosis and the progression of CKD.

The role of textbooks for supporting instruction with inquiry: the case of Active Calculus

In this case study, we investigate how an inquiry-oriented interactive calculus textbook supported one U.S. college instructor’s classroom teaching. We utilized analytical inquiry-oriented frameworks on observation data from a small classroom to capture textbooks’ influence on the instruction conceptualized by the Teacher-Mathematics-Student face of the socio-didactical tetrahedron [Rezat, S., & Sträßer, R. (2012). From the didactical triangle to the Rezat and Sträßer’s tetrahedron model socio-didactical tetrahedron: Artifacts as fundamental constituents of the didactical situation. ZDM - Mathematics Education, 44(5), 641–651. https://doi.org/10.1007/s11858-012-0448-4]. Operationalizing specific inquiry-oriented processes allowed us to examine the depth of the interactions conceptualized by the tetrahedron. The instructor’s reliance on the textbooks, their activities, and their supplemental materials created opportunities for meaningful classroom interactions about calculus, supporting a shift towards inquiry. We conclude by suggesting further research on the role of textbooks in supporting undergraduate mathematics instruction with inquiry and discussing implications for practice.

A first critical analysis of the European approach to damage caused by artificial intelligence enabled by global navigation satellite systems. A bridge to nowhere or a cloud with a silver lining?

ABSTRACT Global Navigation Satellite Systems (GNSS), such as GPS or Galileo, have become indispensable in various sectors, including road traffic, aviation, and emergency response services. With recent technological advancements, GNSS have been incorporated as a fundamental constituent of artificial intelligence (AI) systems. Self-driving vehicles, autonomous aircraft, and drones rely increasingly on GNSS, as these technologies are currently the sole source of globally consistent, precise positioning and timing. However, GNSS are not entirely risk-free as satellite signals can be susceptible to interference and other technical malfunctions may cause disruptive impacts on the proper functioning of AI systems. In such context, this article aims to explore the legal foundations for ascribing liability in case accidents are caused by AI systems due to a GNSS malfunctions, in the light of the recent European regulatory initiatives, namely the AI Act, the AI Liability Directive and the revised Product Liability Directive.

Higher order dispersions effect on high-order soliton interactions

The object of the research is deleting the interaction of the higher order soliton interaction by introducing the third and fourth order dispersions inside an optical fiber. The results are obtained by the simulation of the nonlinear Schrödinger equation, which models the propagation of solitons in the optical fiber using the method of Fast Fourier Transform. The interaction of two higher order solitons due to the attraction of their electric field can lead to losing the solitons' properties. Hence, this can prevent the use of solitons in high-bit-rate optical fiber communication systems because it increases the bit error rate, significantly limiting the potential of the communication system. To resolve this problem, we should diminish the bit rate error by avoiding the interaction of the co-propagative solitons when they are too close. It is well known that, during higher order soliton propagation in the presence of the third order dispersion, the irregular shape of the higher order soliton disappears, and a splitting towards its fundamental constituents occurs after a considerable propagation. As for the fourth order, dispersion gives rise to two dispersive wave sidebands on the red or blue side. Our results reveal that bringing two higher order solitons together in the presence of the fourth order dispersion, a series of interactions between the components generated after their fission is obtained. In the third-order distribution, besides the fourth-order diffusion, the rare form and the supercontinuum generated by the fission of the higher-order solitons disappear, and we get two fundamental solitons propagating in parallel with a temporal shift and some inconsiderable dispersive waves. The most important aspect is that both higher-order dispersions are able to suppress the interactions of higher-order solitons thanks to the time shift induced by the third-order distribution and the intermittent compression caused by the fourth-order scattering. These results can be obtained in practice inside the dispersion-engineered photonic crystal waveguide (PhC-wg), which allows for manipulating the high order dispersion.

Detailed study of quark-hadron duality in spin structure functions of the proton and neutron

Background: The response of hadrons, the bound states of the strong force (QCD), to external probes can be described in two different, complementary frameworks: as direct interactions with their fundamental constituents, quarks and gluons, or alternatively as elastic or inelastic coherent scattering that leaves the hadrons in their ground state or in one of their excited (resonance) states. The former picture emerges most clearly in hard processes with high momentum transfer, where the hadron response can be described by the perturbative expansion of QCD, while at lower energy and momentum transfers, the resonant excitations of the hadrons dominate the cross section. The overlap region between these two pictures, where both yield similar predictions, is referred to as quark-hadron duality and has been extensively studied in reactions involving unpolarized hadrons. Some limited information on this phenomenon also exists for polarized protons, deuterons, and $^{3}\mathrm{He}$ nuclei, but not yet for neutrons.Purpose: In this paper, we present comprehensive and detailed results on the correspondence between the extrapolated deep inelastic structure function ${g}_{1}$ of both the proton and the neutron with the same quantity measured in the nucleon resonance region. Thanks to the fine binning and high precision of our data, and using a well-controlled perturbative QCD (pQCD) fit for the partonic prediction, we can make quantitative statements about the kinematic range of applicability of both local duality and global duality.Method: We use the most updated QCD global analysis results at high $x$ from the Jefferson Lab Angular Momentum Collaboration to extrapolate the spin structure function ${g}_{1}$ into the nucleon resonance region and then integrate over various intervals in the scaling variable $x$. We compare the results with the large data set collected in the quark-hadron transition region by the CLAS Collaboration, including, for the first time, deconvoluted neutron data, integrated over the same intervals. We present this comparison as a function of the momentum transfer ${Q}^{2}$.Results: We find that, depending on the integration interval and the minimum momentum transfer chosen, a clear transition to quark-hadron duality can be observed in both nucleon species. Furthermore, we show, for the first time, the approach to scaling behavior for ${g}_{1}$ measured in the resonance region at sufficiently high momentum transfer.Conclusions: Our results can be used to quantify the deviations from the applicability of pQCD for data taken at moderate energies and can help with extraction of quark distribution functions from such data.

Multi-copper oxidases SKU5 and SKS1 coordinate cell wall formation using apoplastic redox-based reactions in roots.

The primary cell wall is a fundamental plant constituent that is flexible but sufficiently rigid to support the plant cell shape. Although many studies have demonstrated that reactive oxygen species (ROS) serve as important signaling messengers to modify the cell wall structure and affect cellular growth, the regulatory mechanism underlying the spatial-temporal regulation of ROS activity for cell wall maintenance remains largely unclear. Here, we demonstrate the role of the Arabidopsis (Arabidopsis thaliana) multicopper oxidase-like protein skewed 5 (SKU5) and its homolog SKU5-similar 1 (SKS1) in root cell wall formation through modulating ROS homeostasis. Loss of SKU5 and SKS1 function resulted in aberrant division planes, protruding cell walls, ectopic deposition of iron, and reduced nicotinamide adeninedinucleotide phosphate (NADPH) oxidase-dependent ROS overproduction in the root epidermis-cortex and cortex-endodermis junctions. A decrease in ROS level or inhibition of NADPH oxidase activity rescued the cell wall defects of sku5 sks1 double mutants. SKU5 and SKS1 proteins were activated by iron treatment, and iron over-accumulated in the walls between the root epidermis and cortex cell layers of sku5 sks1. The glycosylphosphatidylinositol-anchored motif was crucial for membrane association and functionality of SKU5 and SKS1. Overall, our results identified SKU5 and SKS1 as regulators of ROS at the cell surface for regulation of cell wall structure and root cell growth.

Vagueness and the Evolution of Consciousness

<i>Vagueness and the Evolution of Consciousness</i>

Human death due to H5N1 amid the COVID-19 pandemic and Mpox outbreak: A call for action.

Human death due to H5N1 amid the COVID-19 pandemic and Mpox outbreak: A call for action.

P350 Endoscopic sedation in IBD patients: a propensity score-matched retrospective study

Abstract Background Colonoscopy plays an essential role in the prevention of colorectal cancer screening and the management of inflammatory bowel disease (IBD). For patients with IBD, colonoscopy is advocated for detection of complications, guiding clinical decisions, and cancer surveillance. In most cases, sedation is a fundamental constituent of the procedure, reducing peri-procedural discomfort and improving examination quality. We aimed to compare the dosing of sedative medications and the duration of procedure for IBD patients compared to non-IBD controls in a large-volume endoscopic center. Methods This was a propensity score–matched retrospective study that took place at a high-volume gastroenterology department between June 2020 and September 2021. Colonoscopy data of patients with established IBD including medications and duration of procedure was collected, compared to a 1:2 propensity-scored matched cohort of non-IBD patients. Patients with polyposis, past abdominal surgery, known or suspected malignancy, suspected IBD, incomplete colonoscopies and colonoscopies with inadequate preparation were excluded. The sedation protocol in our institution includes an induction of Midazolam 1-2 mg and Fentanyl of 0.025-0.05 mg administered five minutes prior to procedure. An initial dose of 10-30 mg Propofol is initiated as well, with subsequent increments of 10-20 mg every 1-2 minutes, depending on sedation depth. Results During the study period, 14502 patients including 996 patients with IBD underwent colonoscopy and 4933 patients were excluded in accordance with the exclusion criteria. Propensity score matching was conducted using four characteristics - patient age, gender, American Society of anaesthesiologists score determined by the endoscopist, and endoscopists’ experience. A total of 2289 patients were included in the final analysis (763 IBD patients, 1526 control patients). The groups were similar in administered Propofol sedation doses [IBD- median dose of 100 mg, interquartile ratio (IQR) 70-150 vs control, 100 mg, IQR 80-150, p=0.2). In addition, total procedure time (considered the time from procedure start and end as recorded by the endoscopy nurse) was significantly longer in the IBD group (23 median minutes, IQR 18-30 vs 20 median minutes, IQR 16-27, p&amp;lt;0.0001). There were no differences in terminal ileum intubation rates between the groups (51% in IBD vs 49.5% in control, p=0.5). Conclusion In a retrospective analysis from a large-scale tertiary center cohort, colonoscopies of patients with IBD were significantly longer despite comparable terminal intubation rates; IBD patients did not require more intensive sedation than controls.

Inhibition of cholesterol transport impairs Cav-1 trafficking and small extracellular vesicles secretion, promoting amphisome formation in melanoma cells.

Caveolin-1 (Cav-1) is a fundamental constituent of caveolae, whose functionality and structure are strictly dependent on cholesterol. In this work the U18666A inhibitor was used to study the role of cholesterol transport in the endosomal degradative-secretory system in a metastatic human melanoma cell line (WM266-4). We found that U18666A induces a shift of Cav-1 from the plasma membrane to the endolysosomal compartment, which is involved, through Multi Vesicular Bodies (MVBs), in the formation and release of small extracellular vesicles (sEVs). Moreover, this inhibitor induces an increase in the production of sEVs with chemical-physical characteristics similar to control sEVs but with a different protein composition (lower expression of Cav-1 and increase of LC3II) and reduced transfer capacity on target cells. Furthermore, we determined that U18666A affects mitochondrial function and also cancer cell aggressive features, such as migration and invasion. Taken together, these results indicate that the blockage of cholesterol transport, determining the internalization of Cav-1, may modify sEVs secretory pathways through an increased fusion between autophagosomes and MVBs to form amphisome, which in turn fuses with the plasma membrane releasing a heterogeneous population of sEVs to maintain homeostasis and ensure correct cellular functionality.

Rational design and engineering of polypeptide/protein vesicles for advanced biological applications.

Synthetic vesicles have gained considerable popularity in recent years for numerous biological and medical applications. Among the various types of synthetic vesicles, the utilization of polypeptides and/or proteins as fundamental constituents has garnered significant interest for vesicle construction owing to the unique bio-functionalities inherent in rationally designed amino acid sequences. Especially the incorporation of functional proteins onto the vesicle surface facilitates a wide range of advanced biological applications that are not easily attainable with traditional building blocks, such as lipids and polymers. The main goal of this review is to provide a comprehensive overview of the latest advancements in polypeptide/protein vesicles. Moreover, this review encompasses the rational design and engineering strategies employed in the creation of polypeptide/protein vesicles, including the synthesis of building blocks, the modulation of their self-assembly, as well as their diverse applications. Furthermore, this work includes an in-depth discussion of the key challenges and opportunities associated with polypeptide/protein vesicles, providing valuable insights for future research. By offering an up-to-date review of this burgeoning field of polypeptide/protein vesicle research, this review will shed light on the potential applications of these biomaterials.

ЛОКАЛЬНА ТА РЕГІОНАЛЬНА ІДЕНТИЧНОСТІ В КУЛЬТУРНОМУ ПРОСТОРІ ПОКУТТЯ

This scientific article delves into the analysis of the intricate relationship between local and regional identity within the cultural milieu of Pokuttia. It sheds light on the processes of differentiation and identification that occur within this particular region. Notably, the understanding of the terms "local" and "regional" is contingent upon the scales of the spatial plane where these phenomena are juxtaposed within the realm of cultural geography. A pioneering interdisciplinary approach in cultural regional studies has brought forth a comprehensive examination of various cultural peculiarities specific to the Pokuttia region. These peculiarities encompass elements such as toponyms and the local language prevalent in the Pokuttian area, and their intricate interplay with other social aspects of the region's vibrant life. Through this multidisciplinary lens, a deeper understanding of the intricate tapestry of the region's cultural landscape has been attained. The essence of the discourse is the pivotal role that place assumes as the spatial foundation of local identity. Place emerges as a significant constituent imbued with its own set of symbolic, historical, and ideological attributes. It serves as a profound backdrop against which the nuances of local identity are shaped and expressed. Consequently, the profound interconnection between place and identity becomes a cornerstone for comprehending the complex dynamics within the Pokuttian cultural space. Moreover, this research affirms the inseparable link between local identity and the individual as the principal agent of spatial social reality. The individual, by infusing meaning into a particular place, distinguishes it as either "one's own" or "foreign." This dichotomy is primarily informed by a profound sense of uniqueness and a conscious choice in self-identification within the overarching global context. The interplay among place, individual, and society emerges as the fundamental constituents representing the fabric of local identity – an intricate construct encompassing both personal and collective consciousness within the broader paradigm of cultural space. The insights provided in this article offer valuable contributions to the understanding of the intricate interplay between local and regional identity within the unique cultural context of Pokuttia. Scholars and researchers in the fields of cultural studies, geography, and related disciplines will find these findings pertinent to their exploration of identity dynamics and cultural diversity in various regional contexts

Shedding light on the building blocks of matter and the early universe at CERN

From its early beginnings, the scientific activities at CERN have been driven by the desire to uncover the fundamental constituents of nature and their interactions, and to understand how they shape the evolution of our universe. This article provides an overview of past and current research at CERN.

Glycosaminoglycan Mimetics Obtained by Microwave-Assisted Sulfation of Marine Bacterium Sourced Infernan Exopolysaccharide.

Sulfated glycosaminoglycans (GAGs) are fundamental constituents of both the cell surface and extracellular matrix. By playing a key role in cell-cell and cell-matrix interactions, GAGs are involved in many physiological and pathological processes. To design GAG mimetics with similar therapeutic potential as the natural ones, the specific structural features, among them sulfate content, sulfation pattern, and chain length, should be considered. In the present study, we describe a sulfation method based on microwave radiation to obtain highly sulfated derivatives as GAG mimetics. The starting low-molecular-weight (LMW) derivative was prepared from the infernan exopolysaccharide, a highly branched naturally slightly sulfated heteropolysaccharide synthesized by the deep-sea hydrothermal vent bacterium Alteromonas infernus. LMW highly sulfated infernan derivatives obtained by conventional heating sulfation have already been shown to display GAG-mimetic properties. Here, the potential of microwave-assisted sulfation versus that of the conventional method to obtain GAG mimetics was explored. Structural analysis by NMR revealed that highly sulfated derivatives from the two methods shared similar structural features, emphasizing that microwave-assisted sulfation with a 12-fold shorter reaction time is as efficient as the classical one.

Recent Advances in Micro-/Nanoplastic (MNPs) Removal by Microalgae and Possible Integrated Routes of Energy Recovery.

Reliance on plastic has resulted in the widespread occurrence of micro-/nanoplastics (MNPs) in aquatic ecosystems, threatening the food web and whole ecosystem functions. There is a tight interaction between MNPs and microalgae, as dominant living organisms and fundamental constituents at the base of the aquatic food web. Therefore, it is crucial to better understand the mechanisms underlying the interactions between plastic particles and microalgae, as well as the role of microalgae in removing MNPs from aquatic ecosystems. In addition, finding a suitable route for further utilization of MNP-contaminated algal biomass is of great importance. The present review article provides an interdisciplinary approach to elucidate microalgae-MNP interactions and subsequent impacts on microalgal physiology. The degradation of plastic in the environment and differences between micro- and nanoplastics are discussed. The possible toxic effects of MNPs on microalgal growth, photosynthetic activity, and morphology, due to physical or chemical interactions, are evaluated. In addition, the potential role of MNPs in microalgae cultivation and/or harvesting, together with further safe routes for biomass utilization in biofuel production, are suggested. Overall, the current article represents a state-of-the-art overview of MNP generation and the consequences of their accumulation in the environment, providing new insights into microalgae integrated routes of plastic removal and bioenergy production.

Elevated TGFβ signaling contributes to cerebral small vessel disease in mouse models of Gould syndrome

Cerebral small vessel disease (CSVD) is a leading cause of stroke and vascular cognitive impairment and dementia. Studying monogenic CSVD can reveal pathways that are dysregulated in common sporadic forms of the disease and may represent therapeutic targets. Mutations in collagen type IV alpha 1 (COL4A1) and alpha 2 (COL4A2) cause highly penetrant CSVD as part of a multisystem disorder referred to as Gould syndrome. COL4A1 and COL4A2 form heterotrimers [a1α1α2(IV)] that are fundamental constituents of basement membranes. However, their functions are poorly understood and the mechanism(s) by which COL4A1 and COL4A2 mutations cause CSVD are unknown. We used histological, molecular, genetic, pharmacological, and in vivo imaging approaches to characterize central nervous system (CNS) vascular pathologies in Col4a1 mutant mouse models of monogenic CSVD to provide insight into underlying pathogenic mechanisms. We describe developmental CNS angiogenesis abnormalities characterized by impaired retinal vascular outgrowth and patterning, increased numbers of mural cells with abnormal morphologies, altered contractile protein expression in vascular smooth muscle cells (VSMCs) and age-related loss of arteriolar VSMCs in Col4a1 mutant mice. Importantly, we identified elevated TGFβ signaling as a pathogenic consequence of Col4a1 mutations and show that genetically suppressing TGFβ signaling ameliorated CNS vascular pathologies, including partial rescue of retinal vascular patterning defects, prevention of VSMC loss, and significant reduction of intracerebral hemorrhages in Col4a1 mutant mice aged up to 8 months. This study identifies a novel biological role for collagen α1α1α2(IV) as a regulator of TGFβ signaling and demonstrates that elevated TGFβ signaling contributes to CNS vascular pathologies caused by Col4a1 mutations. Our findings suggest that pharmacologically suppressing TGFβ signaling could reduce the severity of CSVD, and potentially other manifestations associated with Gould syndrome and have important translational implications that could extend to idiopathic forms of CSVD.

Why Definitional Clarity Matters: Implications for the Operationalization of Emotional Well-Being.

The National Institutes of Health (NIH) is increasingly prioritizing research on health-promoting processes. Park et al. (this issue) respond to a call made by NIH to advance the study of emotional well-being (EWB) and to increase understanding of the fundamental constituents of EWB across the lifespan and among diverse subgroups. They propose a definition of EWB that provides an organizing framework for research on 'psychological aspects of well-being' and health. We commend this important first step and urge consideration of three important issues related to operationalization - the process by which an abstract concept is transformed into variables that can be measured - in future research on EWB. We expect that an iterative process of construct refinement and empirical validation will advance the study of EWB, producing scientific discoveries that can be leveraged to enhance health across the lifespan.

A dual-context sequent calculus for the constructive modal logic S4

AbstractThe proof theory of the constructive modal logic S4 (hereafter $\mathsf{CS4}$ ) has been settled since the beginning of this century by means of either standard natural deduction and sequent calculi or by the reconstruction of modal logic through hypothetical and categorical judgments à la Martin-Löf, an approach carried out by using a special kind of sequents, which keeps two separated contexts representing ordinary and enhanced hypotheses, intuitively interpreted as true and valid assumptions. These so-called dual-context sequents, originated in linear logic, are used to define a natural deduction system handling judgments of validity, truth, and possibility, resulting in a formalism equivalent to an axiomatic system for $\mathsf{CS4}$ . However, this proof-theoretical study of $\mathsf{CS4}$ lacks, to the best of our knowledge, its third fundamental constituent, namely a sequent calculus. In this paper, we define such a dual-context formalism, called ${\bf DG_{CS4}}$ , and provide detailed proofs of the admissibility for the ordinary cut rule as well as the elimination of a second cut rule, which manipulates enhanced hypotheses. Furthermore, we make available a formal verification of the equivalence of this proposal with the previously defined axiomatic and dual-context natural deduction systems for $\mathsf{CS4}$ , using the Coq proof-assistant.

Styrofoam Recycling: Relaxation-Densification of EPS by solar heat

The problem of Styrofoam waste is multifaceted. Not only do we need to properly handle the current and future stream of newly manufactured Styrofoam objects, we also have many decades of inert Styrofoam occupying a large fraction of both our active and full/decommissioned landfills, and floating in our oceans and waterways. Solutions are therefore required for recycling current waste streams as well as mitigating huge volumes of legacy Styrofoam waste, distributed globally wherever human populations, landfills, waterways, terminal lakes, reservoirs, or ocean gyres exist. Simply banning Styrofoam, aside from packing peanuts, has been of limited effect because Styrofoam is simply too useful and inexpensive. It is essentially a super-material that is hard to replace and difficult to do without. Every environmentalist who owns a modern television unpacked it from a Styrofoam shell inside a large cardboard box. &#x0D; Polystyrene, the fundamental constituent of Styrofoam, is a common plastic that recycles well. The problem with recycling Styrofoam is that as a foam it is about 98% air by volume, so it must be densified before transport for recycling: the air has to be removed from the foam to return it to its original form as a solid plastic again. The shipment of un-densified Styrofoam for recycling is not economically viable, it would take about 50 trucks to transport only one truck load of fully densified plastic. This equates to un-densified Styrofoam costing more money for paying the costs of factors such as fuel for the vehicle, more drivers, etc. This means, waste Styrofoam must be densified at or near the point of its end-of-use.&#x0D; The focus of our experiments was to see how well zero-carbon, widely distributable methods of heat exposure could densify different types of expanded polystyrene packing peanuts. We show that this can readily be accomplished using the range of temperatures achievable by a typical solar oven (at or above 300°F) — well below the melting temperature of polystyrene (~ 500°F).&#x0D; &#x0D; Rather than using solar heat for this experiment, the proof of concept was demonstrated in a temperature-controlled laboratory oven to maintain well-controlled and stable temperatures to allow the generation of accurate temperature-time-densification curves.&#x0D; At the highest temperatures (~ 300°F) and the longest exposure time (10 minutes), the densification factor ranged from 50 to 53. This is very close to the theoretical limit. Lower temperatures result in partial densification with higher variability. Larger pieces would need longer heat exposure times.&#x0D; To achieve full densification, we suggest using a temperature of at least 300°F (149°C) for 10 or more minutes, for pieces of Styrofoam about the size of packing peanuts. This is easily achievable in solar ovens&#x0D; This process can be readily done in distributed locations at or near the location of end-of-use for Styrofoam products wherever solar ovens can achieve temperatures of about 300°F, thereby making the recycling and upcycling of Styrofoam economically viable for most inhabited regions of the globe, and especially in equatorial areas where plastic waste is especially troublesome.