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Why the Challenger Deep, the deepest point on Earth’s solid surface, is so deep is unclear, but part of the reason must be the age and density of the downgoing plate. Northwest Pacific oceanic crust subducting in the Izu-Bonin-Mariana Trench is Cretaceous and Jurassic, but the age and nature of Pacific oceanic crust subducting in the southernmost Mariana Trench remains unknown. Here we present the first study of seafloor basalts recovered by the full-ocean-depth crewed submersible Fendouzhe from the deepest seafloor around the Challenger Deep, from both the overriding and downgoing plates. 40Ar/39Ar ages indicate that downgo¬ing basalts are Early Cretaceous (ca. 125 Ma), indicating they are part of the Pacific plate rather than the nearby Oligocene Caroline microplate. Downgoing-plate basalts are slightly enriched in incompatible elements but have similar trace element and Hf isotope compositions to other northwest Pacific mid-ocean ridge basalts (MORBs). They also have slightly enriched Sr-Nd-Pb isotope compositions like those of the Indian mantle domain. These features may have formed with contributions from plume-derived components via plume-ridge interac¬tions. One sample from the overriding plate gives an 40Ar/39Ar age of ca. 55 Ma, about the same age as subduction initiation, to form the Izu-Bonin-Mariana convergent margin. Our results suggest that 50%–90% of the Pb budget of Mariana arc magmas is derived from the subducted MORBs with Indian-type isotope affinity. 

A novel additive manufacturing process utilizing the laminated object manufacturing (LOM) technology with woven natural fiber-reinforced biopolymer is investigated in this paper. Traditional synthetic composite materials are products from nonrenewable crude oil with limited end-of-life options, and therefore not environmentally friendly. The continuous woven natural fiber is used to significantly strengthen the mechanical properties of biocomposites and PLA biopolymer as the matrix made the material completely biodegradable. This is one of the promising replacements for synthetic composites in applications such as automotive panels, constructive materials, and sports and musical instruments. A LOM 3D printer prototype has been designed and built by the team using a laser beam in cutting the woven natural fiber reinforcement and molten PLA powder to bind layers together. Tensile and flexural properties of the LOM 3D printed biocomposites were measured using ASTM test standards and then compared with corresponding values measured from pure PLA specimens 3D printed through FDM. Improved mechanical properties from LOM 3D-printed biocomposites were identified by the team. SEM imaging was performed to identify the polymer infusing and fiber-matrix binding situations. This research took advantage of both the material and process’s benefits and combine them into one sustainable practice. 

Ascomycota, the most speciose phylum of fungi, is a complex entity, comprising three diversesubphyla: Pezizomycotina, Saccharomycotina, and Taphrinomycotina. The largest and most diversesubphylum, Pezizomycotina, is a rich tapestry of 16 classes and 171 orders. Saccharomycotina, thesecond largest subphylum, is a diverse collection of seven classes and 12 orders, whileTaphrinomycotina, the smallest, is a unique assembly of six classes and six orders. Over the pastdecade, numerous taxonomic studies have focused on the generic, family, and class classifications ofAscomycota. These efforts, well-documented across various databases, are crucial for acomprehensive understanding of the classification. However, the study of taxonomy at the ordinallevel, a crucial tier in the taxonomic hierarchy, has been largely overlooked. In a global collaborationwith mycologists and lichenologists, this study presents the first comprehensive information on theorders within Pezizomycotina and Taphrinomycotina. The recent taxonomic classification ofSaccharomycotina has led to the exclusion of this subphylum from the present study, as an immediaterevision is not necessary. Each order is thoroughly discussed, highlighting its historical significance,current status, key identification characteristics, evolutionary relationships, ecological and economicroles, future recommendations, and updated family-level classification. Teaching diagrams for thelife cycles of several orders, viz. Asterinales, Helotiales, Hypocreales, Laboulbeniales, Meliolales,Mycosphaerellales, Ophiostomatales, Pezizales, Pleosporales, Phyllachorales, Rhytismatales,Sordariales, Venturiales, Xylariales (Pezizomycotina) and Pneumocystidales,Schizosaccharomycetales and Taphrinales (Taphrinomycotina) are provided. Each diagram is explained with a representative genus/genera of their sexual and asexual cycles of each order. WithinPezizomycotina, Dothideomycetes contains the highest number of orders, with 57, followed bySordariomycetes (52 orders), Lecanoromycetes (21 orders), Eurotiomycetes and Leotiomycetes (12orders each), Laboulbeniomycetes (3 orders), and Arthoniomycetes and Xylonomycetes (2 orderseach). Candelariomycetes, Coniocybomycetes, Geoglossomycetes, Lichinomycetes, Orbiliomycetes,Pezizomycetes, Sareomycetes, and Xylobotryomycetes each contain a single order, whileThelocarpales and Vezdaeales are treated as incertae sedis within Pezizomycotina. Notably, theclasses Candelariomycetes, Coniocybomycetes, Geoglossomycetes, Sareomycetes, andXylonomycetes, all recently grouped under Lichinomycetes, are treated as separate classes based onphylogenetic analysis and current literature. Within Lecanoromycetes, the synonymization ofSporastatiales with Rhizocarpales and Sarrameanales with Schaereriales is not supported in thephylogenetic analysis. These orders are retained separately, and the justifications are provided undereach section as well as in the discussion. Within Leotiomycetes, the order Medeolariales, which wasonce considered part of Helotiales, is treated as a distinct order based on phylogenetic evidence. Theclassification of Medeolariales may change as more data becomes available from different generegions. Lahmiales (Leotiomycetes) is not included in the phylogenetic analysis due to a lack ofmolecular data. Sareomycetes and Xylonomycetes are treated as separate classes. Spathulosporamixed with Lulworthiales and the inclusion of Spathulosporales within Lulworthiomycetidae issupported and extant molecular sampling is important to resolve the phylogenetic boundaries ofmembers of this subclass. The majority of the classes of Pezizomycotina and Taphrinomycotinaformed monophyletic clades in the phylogenetic analysis conducted based on SSU, LSU, 5.8S, TEFand RPB2 sequence data. However, Arthoniomycetes nested with the basal lineage ofDothideomycetes and formed a monophyletic clade also known as the superclass, Dothideomyceta.In Taphrinomycotina, a single order is accepted within each class. 

The ALICE Collaboration reports measurements of the large relative transverse momentum ( $k_T$) component of jet substructure in $pp$and Pb-Pb collisions at center-of-mass energy per nucleon pair $\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$. Enhancement in the yield of such large- $k_{\mathrm{T}}$emissions in head-on Pb-Pb collisions is predicted to arise from partonic scattering with quasiparticles of the quark-gluon plasma. The analysis utilizes charged-particle jets reconstructed by the anti- $k_{\mathrm{T}}$algorithm with resolution parameter $R=0.2$in the transverse-momentum interval $60<p_{\mathrm{T},\mathrm{ch},\mathrm{jet}}<80\mathrm{GeV}/c$. The soft drop and dynamical grooming algorithms are used to identify high transverse momentum splittings in the jet shower. Comparison of measurements in Pb-Pb and $pp$collisions shows medium-induced narrowing, corresponding to yield suppression of high- $k_T$splittings, in contrast to the expectation of yield enhancement due to quasiparticle scattering. The measurements are compared to theoretical model calculations incorporating jet modification due to jet-medium interactions (“jet quenching”), both with and without quasiparticle scattering effects. These measurements provide new insight into the underlying mechanisms and theoretical modeling of jet quenching. 

Abstract This paper presents a study of the inclusive forward J/ψyield as a function of forward charged-particle multiplicity in pp collisions at$$ \sqrt{s} $$ $\sqrt{s}$= 13 TeV using data collected by the ALICE experiment at the CERN LHC. The results are presented in terms of relativeJ/ψyields and relative charged-particle multiplicities with respect to these quantities obtained in inelastic collisions having at least one charged particle in the pseudorapidity range |η|<1. The J/ψmesons are reconstructed via their decay intoμ⁺μ⁻pairs in the forward rapidity region (2.5< y <4). The relative multiplicity is estimated in the forward pseudorapidity range which overlaps with the J/ψrapidity region. The results show a steeper-than-linear increase of the J/ψyields versus the multiplicity. They are compared with previous measurements and theoretical model calculations. 

Abstract Event-by-event fluctuations of the event-wise mean transverse momentum,$$\langle p_{\textrm{T}}\rangle $$ $⟨p_{\text{T}}⟩$, of charged particles produced in proton–proton (pp) collisions at$$\sqrt{s}$$ $\sqrt{s}$= 5.02 TeV, Xe–Xe collisions at$$\sqrt{s_{\textrm{NN}}}$$ $\sqrt{s_{\text{NN}}}$= 5.44 TeV, and Pb–Pb collisions at$$\sqrt{s_{\textrm{NN}}}$$ $\sqrt{s_{\text{NN}}}$= 5.02 TeV are studied using the ALICE detector based on the integral correlator$$\langle \!\langle \Delta p_\textrm{T}\Delta p_\textrm{T}\rangle \!\rangle $$ $⟨⟨\Delta p_{\text{T}}\Delta p_{\text{T}}⟩⟩$. The correlator strength is found to decrease monotonically with increasing produced charged-particle multiplicity measured at midrapidity in all three systems. In Xe–Xe and Pb–Pb collisions, the multiplicity dependence of the correlator deviates significantly from a simple power-law scaling as well as from the predictions of the HIJING and AMPT models. The observed deviation from power-law scaling is expected from transverse radial flow in semicentral to central Xe–Xe and Pb–Pb collisions. In pp collisions, the correlation strength is also studied by classifying the events based on the transverse spherocity,$$S_0$$ $S_0$, of the particle production at midrapidity, used as a proxy for the presence of a pronounced back-to-back jet topology. Low-spherocity (jetty) events feature a larger correlation strength than those with high spherocity (isotropic). The strength and multiplicity dependence of jetty and isotropic events are well reproduced by calculations with the PYTHIA 8 and EPOS LHC models.