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Author Correction: The prognostic impact of Her2 status in early triple negative breast cancer: a Turkish Oncology Group (TOG) study
A solvable model for strongly interacting nonequilibrium excitons
We study the driven-dissipative Bose-Hubbard model with an all-to-all hopping term in the system Hamiltonian, while subject to incoherent pumping and decay from the environment. This system is naturally probed in several recent experiments on excitons in WS 2 /WSe 2 moiré systems, as well as quantum simulators. By positing a particular form of coupling to the environment, we derive the Lindblad jump operators and show that, in certain limits, the system admits a closed-form expression for the steady-state density matrix. Away from the exactly solvable regions, the steady state can be obtained numerically for 100s to 1,000s of sites. We study the nonequilibrium phase diagram and phase transitions, which qualitatively matches the equilibrium phase diagram, agreeing with the intuition that increasing the intensity of the light is equivalent to changing the bosonic chemical potential. However, the steady states are far from thermal states, and the nature of the phase transitions is changed.
Interactive exploration of CNN interpretability via coalitional game theory
Vortex reversal is a precursor of confined bacterial turbulence
Active turbulence, or chaotic self-organized collective motion, is often observed in concentrated suspensions of motile bacteria and other systems of self-propelled interacting agents. To date, there is no fundamental understanding of how geometrical confinement orchestrates active turbulence and alters its physical properties. Here, by combining large-scale experiments, computer modeling, and analytical theory, we have identified a generic sequence of transitions occurring in bacterial suspensions confined in cylindrical wells of varying radii. With increasing the well’s radius, we observed that persistent vortex motion gives way to periodic vortex reversals, four-vortex pulsations, and then well-developed active turbulence. Using computational modeling and analytical theory, we have shown that vortex reversal results from the nonlinear interaction of the first three azimuthal modes that become unstable with the radius increase. The analytical results account for our key experimental findings. To further validate our approach, we reconstructed equations of motion from experimental data. Our findings shed light on the universal properties of confined bacterial active matter and can be applied to various biological and synthetic active systems.
The dietary patterns of water deer recently rediscovered in Northeast China exhibit remarkable similarities to those observed in other regions
Diel partitioning in microbial phosphorus acquisition in the Sargasso Sea
The daily cycle of photosynthetic primary production at the base of marine food webs is often limited by the availability of scarce nutrients. Microbial competition for these scarce resources can be alleviated insofar as the intensity of nutrient uptake and assimilation activities are distributed heterogeneously across organisms over periodic input cycles. Recent analysis of community transcriptional dynamics in the nitrogen-limited subtropical North Pacific gyre revealed evidence of temporal partitioning of nitrogen uptake and assimilation between eukaryotic phytoplankton, cyanobacteria, and heterotrophic bacteria over day-night cycles. Here, we present results from a Lagrangian metatranscriptomic time series survey in the Sargasso Sea and demonstrate temporally partitioned phosphorus uptake in this phosphorus-limited environment. In the Sargasso, heterotrophic bacteria, eukaryotic phytoplankton, and cyanobacteria express genes for phosphorus assimilation during the morning, day, and dusk, respectively. These results support the generality of temporal niche partitioning as an emergent mechanism that can structure uptake of limiting nutrients and facilitate coexistence of diverse microbes in open ocean ecosystems.
Risk factors for postoperative stone formation in pediatric choledochal cysts: a study of 457 cases
Confirmation of the ScanPyramids North Face Corridor in the Great Pyramid of Giza using multi-modal image fusion from three non-destructive testing techniques
Abstract While non-destructive testing (NDT) measurements have been reported individually for archeological surveys of cultural heritage structures, only a few studies to date have attempted to combine NDT images by means of image fusion (IF). In this article, novel multimodal IF results from three different NDT techniques collected at the Chevron located on the Great Pyramid of Giza (aka. as Khufu’s Pyramid) are presented. The Chevron is an assembly of limestone blocks located in front of the recently confirmed ScanPyramids North Face Corridor (SP-NFC), which had been previously hidden for 4500 years. Under the research activities of the ScanPyramids mission, three profiles located on the Chevron were selected to explain multimodal IF in detail and highlight its usefulness in archeology. The NDT techniques employed in this study include ground penetrating radar (GPR), ultrasonic testing (UST), and electrical resistivity tomography (ERT). A discrete wavelet transform (DWT)-based algorithm was employed to merge the reconstructed images from the three techniques for each profile, producing a single composite image. The final fused images contain pertinent information from all modalities, allowing to validate assumptions used to create the individual reconstructed images, and enable a more detailed examination of some of the conclusions reached in the authors’ previous ScanPyramids work.
The reuniens thalamus recruits recurrent excitation in the medial prefrontal cortex
The medial prefrontal cortex (mPFC) and hippocampus are critical for memory retrieval, decision making, and emotional regulation. While ventral CA1 (vCA1) shows direct and reciprocal connections with mPFC, dorsal CA1 (dCA1) forms indirect pathways to mPFC, notably via the thalamic reuniens nucleus (Re). Neuroanatomical tracing has documented structural connectivity of this indirect pathway through Re however, its functional operation is largely unexplored. Here, we used in vivo and in vitro electrophysiology along with optogenetics to address this question. Whole-cell patch-clamp recordings in acute mouse brain slices revealed both monosynaptic excitatory responses and disynaptic feedforward inhibition at Re–mPFC synapses. However, we also identified a prolonged excitation of mPFC by Re. These early monosynaptic and late recurrent components are in marked contrast to the primarily feedforward inhibition characteristic of thalamic inputs to the neocortex. Local field potential recordings in mPFC brain slices revealed prolonged synaptic activity throughout all cortical lamina upon Re activation, with the late excitation enhanced by blockade of parvalbumin neurons and GABA A Rs. In vivo Neuropixels recordings in head-fixed awake mice revealed a similar prolonged excitation of mPFC units by Re activation. In summary, Re output produces recurrent feedforward excitation within mPFC suggesting a potent amplification system in the Re–mPFC network. This may facilitate amplification of dCA1->mPFC signals for which Re acts as the primary conduit, as there is little direct connectivity. In addition, the capacity of mPFC neurons to fire bursts of action potentials in response to Re input suggests that these synapses have a high gain.
Correction for Sibille et al., Efficient mapping of the thalamocortical monosynaptic connectivity in vivo by tangential insertions of high-density electrodes in the cortex
Macroplastic distribution patterns and accumulation in an urbanised Austral subtropical river system
Abstract Plastic products have resulted in enormous pollution in many ecosystem types and regions worldwide. The problem is particularly prominent within aquatic environments, where multiple anthropogenic sources (i.e., agriculture, urbanisation, industries, illegal dumping) are common, exacerbated by interconnectedness between aquatic and terrestrial environments and management challenges. Regional disparities are also common within macroplastic research, with a scarcity of knowledge in African freshwaters. Here, by considering seven riparian sites across four seasons, we determined the abundance and distribution of macroplastic litter along the South African Crocodile River system and its associated tributaries. Macroplastics were sorted and classified into various polymer groups, functional origins, and physical forms for each site and season. We hypothesised that macroplastic abundances would be substantial, with differences among sites and seasons, related to differences in human activities along the river shores, particularly during the summer months when recreational activities was high. We observed significant differences in macroplastic abundances and variation across sites and seasons, with a high macroplastic abundance during autumn (338), while lower total numbers of macroplastics unexpectedly collected during spring and summer (243–263). High proportional abundances of plastic bags and film across all sites and seasons were observed, as well as high abundances of polypropylene polymers. Our study serves as a baseline for understanding seasonal abundance and distribution variations in plastic litter and their driving factors in subtropical river systems, which may help to inform management policies. The study further contributes to resolving knowledge gaps in underrepresented regions, providing novel insights into plastic pollution sources, accumulation, and impacts linked with unique socio-environmental contexts. Thus, it bridges critical data gaps, informing targeted interventions and global comparative analyses in plastic waste management.
Triggering and modulation of a complex behavior by a single peptidergic command neuron in <i>Drosophila</i>
At the end of their growth phase, Drosophila larvae remodel their bodies, glue themselves to a substrate, and harden their cuticle in preparation for metamorphosis. This process—termed pupariation—is triggered by a surge in the hormone ecdysone. Substrate attachment is achieved by a pupariation subprogram called glue expulsion and spreading behavior (GSB). An epidermis-to-CNS Dilp8-Lgr3 relaxin signaling event that occurs downstream of ecdysone is critical for unlocking progression of the pupariation motor program toward GSB, but the factors and circuits acting downstream of Lgr3 signaling remain unknown. Here, using cell-type-specific RNA interference and behavioral monitoring, we identify Myoinhibiting peptide (Mip) as a neuromodulator of multiple GSB action components, such as tetanic contraction, peristaltic contraction alternation, and head-waving. Mip is required in a pair of brain descending neurons, which act temporally downstream of Dilp8-Lgr3 signaling. Mip modulates GSB via ventral nerve cord neurons expressing its conserved receptor, sex peptide receptor (SPR). Silencing of Mip descending neurons by hyperpolarization completely abrogates GSB, while their optogenetic activation at a restricted competence time window triggers GSB-like behavior. Hence, Mip descending neurons have at least two functions: to act as GSB command neurons and to secrete Mip to modulate GSB action components. Our results provide insight into conserved aspects of Mip-SPR signaling in animals, reveal the complexity of GSB control, and contribute to the understanding of how multistep innate behaviors are coordinated in time and with other developmental processes through command neurons and neuropeptidergic signaling.
Synthesis and characterization of antibacterial CMC/AAc/ZnO nanocomposite superabsorbent using gamma radiation
Combining exchangeable <i>P</i> -values
The problem of combining P -values is an old and fundamental one, and the classic assumption of independence is often violated or unverifiable in many applications. There are many well-known rules that can combine a set of arbitrarily dependent P -values (for the same hypothesis) into a single P -value. We show that essentially all these existing rules can be strictly improved when the P -values are exchangeable, or when external randomization is allowed (or both). For example, we derive randomized and/or exchangeable improvements of well-known rules like “twice the median” and “twice the average,” as well as geometric and harmonic means. Exchangeable P -values are often produced one at a time (for example, under repeated tests involving data splitting), and our rules can combine them sequentially as they are produced, stopping when the combined P -values stabilize. Our work also improves rules for combining arbitrarily dependent P -values, since the latter becomes exchangeable if they are presented to the analyst in a random order. The main technical advance is to show that all existing combination rules can be obtained by calibrating the P -values to e-values (using an α -dependent calibrator), averaging those e-values, converting to a level- α test using Markov’s inequality, and finally obtaining P -values by combining this family of tests; the improvements are delivered via recent randomized and exchangeable variants of Markov’s inequality.
Decreased dihydroartemisinin-piperaquine protection against recurrent malaria associated with Plasmodium falciparum plasmepsin 3 copy number variation in Africa
Abstract Dihydroartemisinin-piperaquine (DHA-PPQ) is being recommended in Africa for the management of uncomplicated Plasmodium falciparum malaria and for chemoprevention strategies, based on the ability of piperaquine to delay re-infections. Although therapeutic resistance to piperaquine has been linked to increased copy number in plasmepsin-coding parasite genes ( pfpm ), their effect on the duration of the post-treatment prophylactic period remains unclear. Here, we retrospectively analyzed data from a randomized clinical trial, where patients received either DHA-PPQ or artesunate-amodiaquine for recurrent malaria episodes over two years. We observed an increase in the relative risk of re-infection among patients receiving DHA-PPQ compared to artesunate-amodiaquine after the first malaria season. This was driven by shorter average times to reinfection and coincided with an increased frequency of infections comprising pfpm3 multi-copy parasites. The decline in post-treatment protection of DHA-PPQ upon repeated use in a high transmission setting raises concerns for its wider use for chemopreventive strategies in Africa.
Development of a novel technology for long-term culture and live imaging of excised human tissue
Abstract An integrated understanding of the structure and reactivity of cells, extracellular matrices, and appendages is important for elucidating their functions and mechanisms in our bodies. Three-dimensional imaging using immuno-fluorescent staining with decolorization technology aids in comprehending the internal structure of human organs. However, live imaging of skin dynamics using animal models is highly invasive and unsuitable for humans. The aim of this study was to establish a non-invasive live imaging method for excised human tissue. In this study, to maintain excised human skin tissue in a state similar to a living body, we developed a novel microneedle-based culture technique. This method was evaluated for cytotoxicity detection, inflammatory cytokine release, and tissue morphology. Using microneedles, we cultured excised skin tissue and observed cellular organelles, reactive oxygen species (ROS), and fibrous structures via fluorescent probes and autofluorescence. The microneedle technique prevented cell death and inflammation, enabling long-term culturing. We live-imaged various skin cells, extracellular matrices, and appendage structures, visualizing epidermal cell membranes, mitochondria, and ROS. Collagen and elastin fibers were observed using autofluorescence and second harmonic generation. This approach enabled live imaging for 5 d, providing insights into skin metabolism, regeneration, and responses to stimuli and drugs, ultimately advancing dermatological research.