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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.
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.
Characterizing the variation in safflower seed viability under different storage conditions through lipidomic and proteomic analyses
The biological soundscape of temperate reefs in the Wadden sea
Increased early complication rates following total hip arthroplasty in rheumatoid arthritis patients based on a Japanese nationwide medical claims database study
CFD comparison of novel [emim][DCA] and [emim][MS] ionic liquids for the separation of CO2 greenhouse gas in the membrane contactor
MB based RT-qPCR increase the clinical application of cfEBV DNA for NPC in non-endemic area of China
The synergistic antitumour effect of Carrimycin combined with 5-fluorouracil on colorectal cancer
Experimental verification of superconducting metamaterial quarter-wavelength transmission line resonators with non-uniform mode spacing
Synergistic effect of AP/KP composite oxidizers prepared by electrostatic spraying and promotion of aluminum combustion performance
Development and validation of a risk prediction model for post-traumatic stress disorder among Chinese breast cancer survivors
Benzydamine rescues ethanol-induced teratogenesis in zebrafish FASD model
Abstract Fetal alcohol spectrum disorders (FASD) are a group of physical, behavioral, and cognitive impairments caused by ethanol exposure during pregnancy. Zebrafish have emerged as a useful model for researching FASD and its variants in recent years. Oxidative stress has been identified as the primary damaging pathway, notwithstanding the possibility of other mechanisms at play. In this regard it’s important to put an effort towards antioxidants which can exhibits and bare a potential to counteract the oxidative stress induced by ethanol during embryos development. Previosuly benzydamine has shown to protect macrophages against ethanol-induced condition by stabilizing redox homeostatis. This study aims to repurpose the Non-Steroidal Anti-Inflammatory Drug (NSAID) benzydamine to mitigate ethanol-induced teratogenesis during the early embryonic stage in Zebrafish. Zebrafish embryos were treated with 1% ethanol at 2 h post fertilization (hpf) and co-exposed with benzydamine (5–20 µM) after 2 h of ethanol treatment for 24 h. Reactive oxygen Species (ROS) and biochemical analysis was carried out at 48hpf. 1% ethanol significantly increased the production of ROS along with increased in lipid peroxidation followed by a decrease in glutathione (GSH) level when compoared to the control group (P < 0.001). These conditions were positively encountered by benzydamine (10, 15 µM) and returned to basal level. Involvement of two ethanol metabolizing enzymes cyp2y3 (Cytochrome P450, family 2, subfamily Y, polypeptide 3) and cyp3a65 Cytochrome P450, family 3, subfamily A, polypeptide 65 ) were also studied at 48hpf. 1% ethanol exposure aggregately elevated the expression of these two enzymes which showed a significant decrease in the benzydamine treated groups. Furthermore, the malformations and cellular damage due to 1% ethanol was studied at 96hpf, where 1% ethanol made severe malformation along with muscle fiber alteration, apoptosis in the brain and eye as manifested. These conditions were successfully reverted by benzydamine. In conclusion, ethanol causes oxidative stress, cellular damage along with severe malformation at early embryonic stage, which were partially prevented by the exposure of benzydamine.