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We present the discovery of three protoclusters at z ∼ 3-4 with spectroscopic confirmation in the Canada-France-Hawaii Telescope Legacy Survey Deep Fields. In these fields, we investigate the large-scale projected sky distribution of z ∼ 3-6 Lyman-break galaxies and identify 21 protocluster candidates from regions that are overdense at more than 4σ overdensity significance. Based on cosmological simulations, it is expected that more than 76% of these candidates will evolve into a galaxy cluster of at least a halo mass of 1014 M o at z = 0. We perform follow-up spectroscopy for eight of the candidates using Subaru/FOCAS, Keck II/DEIMOS, and Gemini-N/GMOS. In total we target 462 dropout candidates and obtain 138 spectroscopic redshifts. We confirm three real protoclusters at z = 3-4 with more than five members spectroscopically identified and find one to be an incidental overdense region by mere chance alignment. The other four candidate regions at z ∼ 5-6 require more spectroscopic follow-up in order to be conclusive. A z = 3.67 protocluster, which has 11 spectroscopically confirmed members, shows a remarkable core-like structure composed of a central small region (

In recent years, millisecond-duration radio signals originating in distant galaxies appear to have been discovered in the so-called fast radio bursts (1-9). These signals are dispersed according to a precise physical law and this dispersion is a key observable quantity, which, in tandem with a redshift measurement, can be used for fundamental physical investigations (10,11). Every fast radio burst has a dispersion measurement, but none before now have had a redshift measurement, because of the difficulty in pinpointing their celestial coordinates. Here we report the discovery of a fast radio burst and the identification of a fading radio transient lasting ~6 days after the event, which we use to identify the host galaxy; we measure the galaxy's redshift to be z = 0.492 ± 0.008. The dispersion measure and redshift, in combination, provide a direct measurement of the cosmic density of ionized baryons in the intergalactic medium of [Ω.sub.IGM] = 4.9 ± 1.3 per cent, in agreement with the expectation from the Wilkinson Microwave Anisotropy Probe (12), and including all of the so-called 'missing baryons'. The ~6-day radio transient is largely consistent with the radio afterglow of a short γ-ray burst (13), and its existence and timescale do not support progenitor models such as giant pulses from pulsars, and supernovae. This contrasts with the interpretation (8) of another recently discovered fast radio burst, suggesting that there are at least two classes of bursts., As part of the SUrvey for Pulsars and Extragalactic Radio Bursts (SUPERB) project at the Parkes radio telescope, we perform real-time searches of the sky at high time resolution (see [...]

The photolysis of diazirines in the presence of C60 is reported.

The current growing demand for Conservation Agriculture (CA) at the national level in the countries of the Asia-Pacific region presents an opportunity to promote its widespread adoption and up-scaling through national policy and institutional support that appears necessary. Despite the obvious benefits of CA, it does not spread automatically unless the constraints that hinder adoption are understood and addressed in specific situations. These can include a combination of intellectual, social, financial, biophysical, technical, infrastructure constraints, or policy related support. Knowing what the bottlenecks are is important in developing strategies to overcome them. This paper presents: (a) some of the generic policy opportunities that exist for the adoption and uptake of CA; (b) a summary proceedings and outcome of the Regional Expert Consultation Workshop held in Beijing and sponsored by FAO Regional Office for Asia-Pacific which describes the status of CA in the Asia-Pacific region; (c) the challenges to CA adoption and uptake in the Asia-Pacific region; and (d) the conditions that need to be taken into account in designing and promoting policy and institutional support strategies for up-scaling CA. [ABSTRACT FROM AUTHOR]

Cytokine receptor-like factor 2 (CRLF2) and interleukin-7 receptor α (IL-7Rα) form a receptor for thymic stromal lymphopoietin (TSLP). A somatic mutation consisting of the substitution of five amino acids (SLLLL) in the transmembrane domain of CRLF2 with three amino acids, including glutamic acid, isoleucine, and methionine (insEIM), which has been identified in acute lymphocytic leukemia, causes the TSLP-independent dimerization with IL-7Rα and activation. However, the dimerization mechanism remains unclear. In this study, we examined the involvement of the amino acids in the transmembrane domains of EIM CRLF2 and IL-7Rα in TSLP-independent activation. HEK293 cells were transfected with vectors encoding CRLF2 and IL-7Rα, or their mutants, in which the amino acid of the transmembrane domain was replaced with alanine. STAT5 phosphorylation was detected using western blotting, and receptor dimerization was analyzed using the NanoBiT assay. The substitution of glutamic acid within the insEIM mutation for alanine failed to cause the STAT5 phosphorylation in the absence of TSLP. Moreover, the alanine substation of the specific leucine residues in the transmembrane domains of both CRLF2 and IL-7Rα abrogated the TSLP-independent signal transduction and dimerization. The mutation of IL-7Rα W264 partially reduced the phosphorylation of STAT5 without affecting receptor dimerization. These results suggest that the amino acids in the transmembrane domains of EIM CRLF2 and IL-7Rα play at least three possible functions: interaction through hydrogen bonds, hydrophobic interaction, and signal transduction. Our findings contribute to a better understanding of the function of the transmembrane domains of cytokine receptors in their dimerization and signal transduction., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Although StayGold is a bright and highly photostable fluorescent protein, its propensity for obligate dimer formation may hinder applications in molecular fusion and membrane targeting. To attain monovalent as well as bright and photostable labeling, we engineered tandem dimers of StayGold to promote dispersibility. On the basis of the crystal structure of this fluorescent protein, we disrupted the dimerization to generate a monomeric variant that offers improved photostability and brightness compared to StayGold. We applied the new monovalent StayGold tools to live-cell imaging experiments using spinning-disk laser-scanning confocal microscopy or structured illumination microscopy. We achieved cell-wide, high-spatiotemporal resolution and sustained imaging of dynamic subcellular events, including the targeting of endogenous condensin I to mitotic chromosomes, the movement of the Golgi apparatus and its membranous derivatives along microtubule networks, the distribution of cortical filamentous actin and the remolding of cristae membranes within mobile mitochondria., (© 2023. The Author(s).)

The segmental organization of the vertebral column is established early in embryogenesis, when pairs of somites are rhythmically produced by the presomitic mesoderm (PSM). The tempo of somite formation is controlled by a molecular oscillator known as the segmentation clock 1,2 . Although this oscillator has been well-characterized in model organisms 1,2 , whether a similar oscillator exists in humans remains unknown. Genetic analyses of patients with severe spine segmentation defects have implicated several human orthologues of cyclic genes that are associated with the mouse segmentation clock, suggesting that this oscillator might be conserved in humans 3 . Here we show that human PSM cells derived in vitro-as well as those of the mouse 4 -recapitulate the oscillations of the segmentation clock. Human PSM cells oscillate with a period two times longer than that of mouse cells (5 h versus 2.5 h), but are similarly regulated by FGF, WNT, Notch and YAP signalling 5 . Single-cell RNA sequencing reveals that mouse and human PSM cells in vitro follow a developmental trajectory similar to that of mouse PSM in vivo. Furthermore, we demonstrate that FGF signalling controls the phase and period of oscillations, expanding the role of this pathway beyond its classical interpretation in 'clock and wavefront' models 1 . Our work identifying the human segmentation clock represents an important milestone in understanding human developmental biology.

Individual cellular activities fluctuate but are constantly coordinated at the population level via cell-cell coupling. A notable example is the somite segmentation clock, in which the expression of clock genes (such as Hes7) oscillates in synchrony between the cells that comprise the presomitic mesoderm (PSM) 1,2 . This synchronization depends on the Notch signalling pathway; inhibiting this pathway desynchronizes oscillations, leading to somite fusion 3-7 . However, how Notch signalling regulates the synchronicity of HES7 oscillations is unknown. Here we establish a live-imaging system using a new fluorescent reporter (Achilles), which we fuse with HES7 to monitor synchronous oscillations in HES7 expression in the mouse PSM at a single-cell resolution. Wild-type cells can rapidly correct for phase fluctuations in HES7 oscillations, whereas the absence of the Notch modulator gene lunatic fringe (Lfng) leads to a loss of synchrony between PSM cells. Furthermore, HES7 oscillations are severely dampened in individual cells of Lfng-null PSM. However, when Lfng-null PSM cells were completely dissociated, the amplitude and periodicity of HES7 oscillations were almost normal, which suggests that LFNG is involved mostly in cell-cell coupling. Mixed cultures of control and Lfng-null PSM cells, and an optogenetic Notch signalling reporter assay, revealed that LFNG delays the signal-sending process of intercellular Notch signalling transmission. These results-together with mathematical modelling-raised the possibility that Lfng-null PSM cells shorten the coupling delay, thereby approaching a condition known as the oscillation or amplitude death of coupled oscillators 8 . Indeed, a small compound that lengthens the coupling delay partially rescues the amplitude and synchrony of HES7 oscillations in Lfng-null PSM cells. Our study reveals a delay control mechanism of the oscillatory networks involved in somite segmentation, and indicates that intercellular coupling with the correct delay is essential for synchronized oscillation.

Presynaptic plasticity is known to modulate the strength of synaptic transmission. However, it remains unknown whether regulation in presynaptic neurons can evoke excitatory and inhibitory postsynaptic responses. We report here that the Caenorhabditis elegans homologs of MAST kinase, Stomatin, and Diacylglycerol kinase act in a thermosensory neuron to elicit in its postsynaptic neuron an excitatory or inhibitory response that correlates with the valence of thermal stimuli. By monitoring neural activity of the valence-coding interneuron in freely behaving animals, we show that the alteration between excitatory and inhibitory responses of the interneuron is mediated by controlling the balance of two opposing signals released from the presynaptic neuron. These alternative transmissions further generate opposing behavioral outputs necessary for the navigation on thermal gradients. Our findings suggest that valence-encoding interneuronal activity is determined by a presynaptic mechanism whereby MAST kinase, Stomatin, and Diacylglycerol kinase influence presynaptic outputs., Competing Interests: The authors declare no competing interest., (Copyright © 2020 the Author(s). Published by PNAS.)

Convergent advances in optical imaging and genetic engineering have fueled the development of new technologies for biological visualization. Those technologies include genetically encoded indicators based on fluorescent proteins (FPs) for imaging ions, molecules, and enzymatic activities "to spy on cells," as phrased by Roger Tsien, by sneaking into specific tissues, cell types, or subcellular compartments, and reporting on specific intracellular activities. Here we review the current range of unimolecular indicators whose working principle is the conversion of a protein conformational change into a fluorescence signal. Many of the indicators have been developed from fluorescence resonance energy transfer- and single-FP-based approaches., (Copyright © 2015 Elsevier Inc. All rights reserved.)

An increasingly powerful approach for studying brain circuits relies on targeting genetically encoded sensors and effectors to specific cell types. However, current approaches for this are still limited in functionality and specificity. Here we utilize several intersectional strategies to generate multiple transgenic mouse lines expressing high levels of novel genetic tools with high specificity. We developed driver and double reporter mouse lines and viral vectors using the Cre/Flp and Cre/Dre double recombinase systems and established a new, retargetable genomic locus, TIGRE, which allowed the generation of a large set of Cre/tTA-dependent reporter lines expressing fluorescent proteins, genetically encoded calcium, voltage, or glutamate indicators, and optogenetic effectors, all at substantially higher levels than before. High functionality was shown in example mouse lines for GCaMP6, YCX2.60, VSFP Butterfly 1.2, and Jaws. These novel transgenic lines greatly expand the ability to monitor and manipulate neuronal activities with increased specificity., (Copyright © 2015 Elsevier Inc. All rights reserved.)

One of the most awaited techniques in modern physiology is the sensitive detection of spatiotemporal electrical activity in a complex network of excitable cells. The use of genetically encoded voltage probes has been expected to enable such analysis. However, in spite of recent progress, existing probes still suffer from low signal amplitude and/or kinetics too slow to detect fast electrical activity. Here, we have developed an improved voltage probe named Mermaid2, which is based on the voltage-sensor domain of the voltage-sensing phosphatase from Ciona intestinalis and Förster energy transfer between a pair of fluorescent proteins. In mammalian cells, Mermaid2 permits ratiometric readouts of fractional changes of more than 50% over a physiologically relevant voltage range with fast kinetics, and it was used to follow a train of action potentials at frequencies of up to 150 Hz. Mermaid2 was also able to detect single action potentials and subthreshold voltage responses in hippocampal neurons in vitro, in addition to cortical electrical activity evoked by sound stimuli in single trials in living mice.

Cesarean sections sometimes save the lives of mothers and babies; however, they are excessively used compared to medical necessity, which is influenced by various factors that are explored in this article. Since, in most cases the risks of cesarean sections are greater than the benefits, particularly in cesareans that are not medically indicated, it is astonishing that cesarean surgery is the most common surgical procedure, taking away resources from medically necessary care. While economic incentive is counted among the reasons for the increasing cesarean trend, the situation is not so simple since many factors interact to cause the trend. Since reversal of the vaginal birth after cesarean (VBAC) trend downward is correlated with revised policy statements by e.g. American College of Obstetricians and Gynecologists (ACOG), which have since been partially moderated, it became much more difficult for medical institutions to provide VBACs due to concerns about liability. Although whether to give birth by cesarean delivery is a matter for informed consent, yet childbearing women are influenced significantly by their health service providers' opinions. Even though the World Health Organization (WHO) recommends the most peripheral level of maternity care for normal pregnancy and childbirth that is safe using midwives, yet the percentage of midwife deliveries is low. Among other things, it has been suggested that more childbirth by midwife delivery and in out-of-hospital settings can reduce medically unnecessary cesareans and the undue risks associated with them, and free up medical resources for those in need.

Cyclic GMP (cGMP) regulates many physiological processes by cooperating with the other signaling molecules such as cyclic AMP (cAMP) and Ca(2+). Genetically encoded sensors for cGMP have been developed based on fluorescence resonance energy transfer (FRET) between fluorescent proteins. However, to analyze the dynamic relationship among these second messengers, combined use of existing sensors in a single cell is inadequate because of the significant spectral overlaps. A single wavelength indicator is an effective alternative to avoid this problem, but color variants of a single fluorescent protein-based biosensor are limited. In this study, to construct a new color fluorescent sensor, we converted the FRET-based sensor into a single wavelength indicator using a dark FRET acceptor. We developed a blue fluorescent cGMP biosensor, which is spectrally compatible with a FRET-based cAMP sensor using cyan and yellow fluorescent proteins (CFP/YFP). We cotransfected them and loaded a red fluorescent probe for Ca(2+) into cells, and accomplished triple-parameter fluorescence imaging of these cyclic nucleotides and Ca(2+), confirming the applicability of this combination to individually monitor their dynamics in a single cell. This blue fluorescent sensor and the approach using this FRET pair would be useful for multiparameter fluorescence imaging to understand complex signal transduction networks.

We report a method for specifically labelling the surface of cells with two kinds of chemical probes (near-infrared (NIR) fluorescent probes and magnetic resonance (MR) imaging probes) via two genetically expressed tags, and demonstrate the application for in vitro and in vivo dual imaging.

Fluorescence resonance energy transfer (FRET) between fluorescent proteins is a powerful tool for visualization of signal transduction in living cells, and recently, some strategies for imaging of dual FRET pairs in a single cell have been reported. However, these necessitate alteration of excitation light between two different wavelengths to avoid the spectral overlap, resulting in sequential detection with a lag time. Thus, to follow fast signal dynamics or signal changes in highly motile cells, a single-excitation dual-FRET method should be required. Here we reported this by using four-color imaging with a single excitation light and subsequent linear unmixing to distinguish fluorescent proteins. We constructed new FRET sensors with Sapphire/RFP to combine with CFP/YFP, and accomplished simultaneous imaging of cAMP and cGMP in single cells. We confirmed that signal amplitude of our dual FRET measurement is comparable to of conventional single FRET measurement. Finally, we demonstrated to monitor both intracellular Ca(2+) and cAMP in highly motile cardiac myocytes. To cancel out artifacts caused by the movement of the cell, this method expands the applicability of the combined use of dual FRET sensors for cell samples with high motility.

Objectives: The present study was conducted to assess current implementation of discharge planning in the care of hospitalized older adults, and to examine the association between implementation and involvement of home care providers at hospitals., Methods: The subjects were 434 hospitals with 100 beds or more for general patients, nationwide. We conducted a questionnaire survey by mail of hospital staff responsible for the discharge planning, and assessed to what extent home care providers were associated with the implementation of discharge planning in the hospitals. The subjects were divided into two groups: an association group (138 hospitals) in which home care providers were associated with implementation in the hospitals, and a not-association group (296 hospitals). We compared the proportions of implementation of discharge planning between the two groups, and calculated odds-ratios. In the analysis, we controlled for affiliated institution and home care services., Results: The association group showed significantly higher proportions of implementation for 13 items in a total 24 items for discharge planning than the not-association group (range of odds-ratio: 2.430-5.497). The three highest odds ratios were observed for "Arrangement and guidance for home care by outreach prior to discharge" [OR= 5.497, 95% confidence interval (CI): 2.604-11.602], "Adjusting relationship between patient and family" (OR=4.871, 95%CI: 1.323-17.930) and "Refining medical and nursing care so as to be sustainable at home" (OR = 4.740, 95%CI: 1.825-12.311)., Conclusions: The present study showed that hospitals with involvement of home care providers had higher proportions of implementation of discharge planning for hospitalized older adults concerning "Arrangement and guidance for home care by outreach prior to discharge", "Adjusting relationship between patient and family", "Refining medical and nursing care so as to be sustainable at home" and so on. Further study should examine the effect of discharge planning on length of stay, rate of readmission, patient and family member's satisfaction controlling for patient characteristics and hospital's role in the community.

In physiological and pathological events, extracellular ATP plays an important role by controlling several types of purinergic receptors and changing cytoskeleton dynamics. To know the process of ATP-dependent cytoskeleton remodeling, we focused on cofilin, a key regulator of actin cytoskeleton, and investigated the dynamics of cofilin in PC12 cells through fluorescent protein-labeled cofilin and actin, Ca(2+) imaging, and fluorescence resonance energy transfer (FRET) techniques. As a result, ATP induced intracellular Ca(2+) increase, following cofilin rods' formation. ATP-induced cofilin rods' formation was not observed in cells expressing unphosphorylatable variant of cofilin. A P2X receptor agonist, but not P2Y, induced the formation of cofilin rods, whereas calmodulin and calcineurin inhibitors suppressed it. These results indicate that Ca(2+) influx through P2X receptors induces the formation of cofilin rods via calcineurin-dependent dephosphorylation of cofilin. This pathway might be one candidate to explain the effects of ATP on neuronal development and injury.