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Considering the randomness of the fire location and the high probability of tunnel fires occurring near the tunnel portal, a series of experiments were conducted using a 1:15 tunnel model. In the event of double fires with an extra external fire source except for the internal fire source, the characteristics of smoke spread and smoke stratification are influenced by asymmetric flow fields. The distribution and decay of the smoke temperature beneath the tunnel ceiling, the smoke layer thickness, and the smoke layer stratification were measured and analyzed. The findings indicate that despite a considerable dimensionless fire spacing, the maximum temperature remains longitudinally positioned between the two fire sources. The characteristics of temperature attenuation showed the variation with the dimensionless fire spacing, particularly when the fire spacing was minimal. Furthermore, a model of the pre-exponential factor was built. There was a stable area of smoke layer thickness upstream of the internal fire, showing no sensitivity to variations in dimensionless fire spacing or pool size. Additionally, an obvious smoke interface drop was found between two fire sources. [ABSTRACT FROM AUTHOR]

Multiscale processes from synoptic disturbances to diurnal cycles during the record-breaking heavy rainfall in summer 2020 were examined in this study. The heavy rainfall consisted of eight episodes, each lasting about 5 days, and were associated with two types of synoptic disturbances. The type-1 episodes featured a northwestward extending western Pacific subtropical high (WPSH), while the type-2 episodes had approaching midlatitude troughs with southward retreat in the WPSH. Each heavy rainfall episode had 2–3 occurrences of nocturnal low-level jets (NLLJs), in close association with intense rainfall in the early morning. The NLLJs formed partly due to the geostrophic wind by increased pressure gradients under both types of synoptic disturbances. The NLLJs were also driven by the ageostrophic wind that veered to maximum southerlies at late night due to the boundary layer inertial oscillation. The diurnal amplitudes of low-level southerlies increased remarkably after the onset of type-1 episodes, in which the extending WPSH provided strong daytime heating from solar radiation. By contrast, the wind diurnal amplitudes were less changed after the onset of type-2 episodes. The NLLJs strengthened the mesoscale low-level ascent, net moisture flux convergence, and convective instability in elevated warm moist air, which led to the upscale growth of MCSs at the northern terminus of the LLJ after midnight. The MCSs-induced mei-yu rainband was reestablished in Central China during the type-1 episodes with the increased diurnal variations. The findings highlight that the regional diurnal cycles of low-level winds in response to synoptic disturbances can strongly regulate mesoscale convective activities in a downscaling manner, and thus produce heavy rainfall. [ABSTRACT FROM AUTHOR]

The small intestinal (SI) microbiota plays an important role in human health and disease. Current methods based on fecal analysis do not provide an accurate representation of the SI microbiome. This article introduces an ingestible sensor for the quantification of Escherichia coli (E. coli) in the SI by developing the fluorescent thread‐based ingestible pill analytical device (TPAD) using fluorescent gold nanoclusters (AuNCs) coupled with molecularly imprinted polymers (MIPs). Quantitative detection lies in the change in fluorescence signal on thread as proportional to target bacteria concentrations using a smartphone. Utilizing a pH‐sensitive enteric coating, this device facilitates localized sampling of the SI microbiome. Hydrophilic beads are employed to autonomously seal the device after sampling, offering a self‐locking mechanism. The sensor demonstrates a linear range for E. coli detection between 2.0 × 103 and 14.0 × 103 CFU mL−1 with an R2 of 0.9975 and a detection limit (LOD) of 400.0 × 102 CFU mL−1. The sensor also shows remarkable precision and acceptable accuracy for monitoring E. coli levels in in vivo animal studies compared to commercially available test kits. The developed TPAD, therefore, offers a novel, low‐cost, and non‐invasive method for rapidly diagnosing gastrointestinal (GI)‐related medical conditions and studying host–microbiome interactions. [ABSTRACT FROM AUTHOR]

Background: Gliomas account for the major part of primary brain tumors. Based on their histology and molecular alternations, adult gliomas have been classified into four grades, each with distinct biology and outcome. Previous studies have focused on cell-line-based models and patient-derived xenografts (PDXs) from patient-derived glioma cultures for grade IV glioblastoma. However, the PDX of lower grade diffuse gliomas, particularly those harboring the endogenous IDH mutation, are scarce due to the difficulty growing glioma cells in vitro and in vivo. The purpose of this study was to develop a panel of patient-derived subcutaneous xenografts of different grade gliomas that represented the heterogeneous histopathologic and genetic features of human gliomas. Methods: Tumor pieces from surgical specimens were subcutaneously implanted into flanks of NOD-Prkdcscid ll2rgnull mice. Then, we analyzed the association between the success rate of implantation with clinical parameters using the Chi square test and resemblance to the patient's original tumor using immunohistochemistry, immunofluorescence, short tandem repeat analysis, quantitative real-time polymerase chain reaction, and whole-exome sequencing. Results: A total of 11 subcutaneous xenografts were successfully established from 16 surgical specimens. An increased success rate of implantation in gliomas with wild type isocitrate dehydrogenase (IDH) and high Ki67 expression was observed compared to gliomas with mutant IDH and low Ki67 expression. Recurrent and distant aggressive xenografts were present near the primary implanted tumor fragments from WHO grades II to IV. The xenografts histologically represented the corresponding patient tumor and reconstituted the heterogeneity of different grade gliomas. However, increased Ki67 expression was found in propagated xenografts. Endothelial cells from mice in patient-derived xenografts over several generations replaced the corresponding human tumor blood vessels. Short tandem repeat and whole-exome sequencing analyses indicated that the glioma PDX tumors maintained their genomic features during engraftments over several generations. Conclusions: The panel of patient-derived glioma xenografts in this study reproduced the diverse heterogeneity of different grade gliomas, thereby allowing the study of the growth characteristics of various glioma types and the identification of tumor-specific molecular markers, which has applications in drug discovery and patient-tailored therapy. [ABSTRACT FROM AUTHOR]

A succession of MCSs developed during the last week of October 2016 and produced extreme heavy rainfall in central China. The event underwent an evident shift from a mei-yu-like warm scenario to an autumn cold scenario. Diurnal cycles of rainfall and low-level winds may be modulated by the shifting of large-scale atmospheric conditions. We conducted observational analyses and numerical experiments to examine how large-scale circulations influenced rainfall systems through diurnally varying processes. The results show that, in the first half (warm) period of the event, intense rainfall mostly occurred in eastern-central China with an early morning peak. It was closely related to a nocturnal southwesterly low-level jet (NLLJ) on the flank of the western Pacific subtropical high. The NLLJ formed near midnight in southern China where ageostrophic wind rotated clockwise due to Blackadar's inertial oscillation. The NLLJ extended downstream to central China during the predawn hours due to the horizontal advection of momentum. Both the formation and extension of the NLLJ were supported by an enhanced subtropical high that provided relatively warm conditions with surface heating for boundary layer inertial oscillation and strong background southwesterly winds for momentum transport. The NLLJ induced MCSs at its northern terminus where the low-level ascent, moisture flux convergence, and convective instability were enhanced during the predawn hours. In the second half period with an intrusion of cold air, the diurnal amplitude of low-level winds became small under relatively cold and cloudy conditions. Moderate rainfall tended to occur in western-central China with a peak after midnight, most likely due to frontogenetic processes, upslope lifting, and nighttime cloud-top cooling. [ABSTRACT FROM AUTHOR]

Animal‐borne biologging technology allows researchers to understand the physiological responses of wild animals, especially songbirds, to environmental changes. Songbirds are of interest in studying these responses because of their visibility and relatively small body size yet high energetic demand of their various life‐history stages (e.g., molt, migration, breeding). Previous methods for monitoring responses, such as heart rate activity, have relied on surgical implantation of electrodes connected to bulky electronic devices which affect the well‐being of birds, indirectly influence bird behavior and create stress artifacts. A non‐invasive, lightweight solution is needed. This study introduces eutectogels, a long‐lasting gel made from deep eutectic solvents, combined with conductive threads and a wireless device to monitor the heart rate of house sparrows noninvasively through skin contact. In this work, heart rate and respiration rate measurements are validated on birds under anesthesia. These tests are repeated on birds that are awake but restrained. The eutectogel outperforms commercial electrodes and gels, yielding high signal‐to‐noise ratio measurements on restrained birds. The respiration rate is extracted and processed electronically from motion artifacts in the recorded signals without the need for a separate dedicated sensor. The system shows promise for future field studies on free‐living species. [ABSTRACT FROM AUTHOR]

The smoke back-layering length and the critical ventilation velocity in double fire scenarios where the fire sources were both inside and outside the tunnel were studied by small-scale tests and theoretical analysis. Results showed that the smoke back-layering length increased with an increase of the fire separating distance when the dimensionless fire separating distance was less than 3, and the values were larger than the results of a single internal fire at each fire separating distance. The dimensionless critical ventilation velocity segmentally increased with the increase of the dimensionless fire separating distance when the dimensionless fire separating distance was less than 10, and then remained constant. Moreover, the constant value was found to be close to that in the case of a single tunnel fire. In addition, an empirical model of dimensionless critical ventilation velocity was established for the double tunnel fire scenario both inside and outside a tunnel. • Tunnel fire scenarios occurring both inside and outside a tunnel were studied. • Critical velocity increased first and then remained stable with increasing spacing. • An empirical model of dimensionless critical ventilation velocity was established. [ABSTRACT FROM AUTHOR]

There is a need to develop low-cost and compact frequency reconfigurable antennas with continuous frequency tuning capability. Existing approaches rely on dedicated electrical, mechanical, or MEMS-based approaches to reconfigure the antenna, which requires extra components and fabrication steps. In this paper, we propose a physics-based approach to realize tunable helical antennas based on a shape memory alloy (SMA). By utilizing the temperature-induced irreversible mechanical deformation of the SMA, the temperature-controlled antenna can continuously change its resonant frequency and lock the state when the desired frequency response is achieved. The height of the helical antenna changes in response to applied temperatures. No additional circuitry or mechanical modules are required for the reconfiguration of the antenna geometry. The fabricated helical antenna can shift resonant frequency between 150 and 195 MHz with a tuning sensitivity of 284 kHz/°C. [ABSTRACT FROM AUTHOR]

Microneedles offer a convenient transdermal delivery route with potential for long term sustained release of drugs. However current microneedle technologies may not have the mechanical properties for reliable and stable penetration (e.g. hydrogel microneedles). Moreover, it is also challenging to realize microneedle arrays with large size and high flexibility. There is also an inherent upper limit to the amount and kind of drugs that can be loaded in the microneedles. In this paper, we present a new class of polymeric porous microneedles made from biocompatible and photo-curable resin that address these challenges. The microneedles are unique in their ability to load solid drug formulation in concentrated form. We demonstrate the loading and release of solid formulation of anesthetic and non-steroidal anti-inflammatory drugs, namely Lidocaine and Ibuprofen. Paper also demonstrates realization of large area (6 × 20 cm2) flexible and stretchable microneedle patches capable of drug delivery on any body part. Penetration studies were performed in an ex vivo porcine model supplemented through rigorous compression tests to ensure the robustness and rigidity of the microneedles. Detailed release profiles of the microneedle patches were shown in an in vitro skin model. Results show promise for large area transdermal delivery of solid drug formulations using these porous microneedles. [ABSTRACT FROM AUTHOR]

This paper proposes a low-noise readout circuit with a noise floor of 11 fA rms / sq (Hz) and a bandwidth of 1.3 MHz. The novel electrostatic discharge (ESD) leakage current cancellation stage allows the circuit to detect sub-pA range current input. A total trans-impedance gain of 160 dB is obtained by a current preamplification stage with a 100 × current gain followed by a transimpedance amplifier (TIA) with a 1 Mohm feedback resistive gain. The reader is designed in a 0.18 μ m CMOS process and consumes 5.6 mW from a 1.8 V supply. [ABSTRACT FROM AUTHOR]

• A surface-enhanced Raman scattering quantitative detection method was developed. • Centrifugal treatment significantly increased the hot spot density. • The quantitative linear range was decreased to nanomolar level (R2 > 0.992). • The method exhibited high repeatability on a portable Raman spectrometer (RSD < 2%). Quantitative detection for nanomolar analytes is a challenge for surface-enhanced Raman scattering (SERS). In this report, a SERS method which combined with an internal standard method and a two-step centrifugation method was established for trace analysis of two drugs using a portable Raman spectrometer. Metformin hydrochloride was used as an internal standard for phenformin hydrochloride to increase the linearity of SERS detection, while, streptomycin sulfate was used for tigecycline. The two-step centrifugation method for sample preparation increased the density of hot spots and the concentration of analyte by accumulating silver nanoparticles. Therefore, the detection sensitivity was significantly improved. Furthermore, the repeatability of SERS signals was increased by adding 200 µL of the sample solution into a slit-type quartz cuvette to make the excitation light transmit through a heavy thickness sample solution. The RSDs of SERS signal intensity ratio of phenformin hydrochloride and tigecycline to internal standard were 1% and 1.6%, respectively. Finally, phenformin hydrochloride and tigecycline exhibited a good linearity in the range of 1–500 nM (R2 = 0.9976) and 10–750 nM (R2 = 0.9926), respectively. In a word, this method greatly improved the lower limit of quantitation of SERS, and laid foundation for rapid and convenient quantitative detection of low concentration drug in biological samples. [ABSTRACT FROM AUTHOR]

Microneedles offer a convenient transdermal delivery route with potential for long term sustained release of drugs. However current microneedle technologies may not have the mechanical properties for reliable and stable penetration (e.g. hydrogel microneedles). Moreover, it is also challenging to realize microneedle arrays with large size and high flexibility. There is also an inherent upper limit to the amount and kind of drugs that can be loaded in the microneedles. In this paper, we present a new class of polymeric porous microneedles made from biocompatible and photo-curable resin that address these challenges. The microneedles are unique in their ability to load solid drug formulation in concentrated form. We demonstrate the loading and release of solid formulation of anesthetic and non-steroidal anti-inflammatory drugs, namely Lidocaine and Ibuprofen. Paper also demonstrates realization of large area (6 × 20 cm2) flexible and stretchable microneedle patches capable of drug delivery on any body part. Penetration studies were performed in an ex vivo porcine model supplemented through rigorous compression tests to ensure the robustness and rigidity of the microneedles. Detailed release profiles of the microneedle patches were shown in an in vitro skin model. Results show promise for large area transdermal delivery of solid drug formulations using these porous microneedles. [ABSTRACT FROM AUTHOR]

Monsoon southerlies can be particularly active for days and produce substantial rainfall over East Asia. These multiday episodes of southerly monsoon surge may exhibit distinct diurnal variations due to regional forcings under given large-scale conditions. This study categorizes the southerly surges into two types with different wind diurnal variations to clarify their influence on rainfall over East Asia. In the summers of 1998–2019, there are 63 episodes of southerly surges with large wind diurnal cycles and 55 episodes with small diurnal cycles. The first type of southerly surges usually occurs with anomalous low-level warming over southeastern China related to the westward extension of the western Pacific subtropical high. The second type of southerly surges instead occurs with anomalous cooling due to the deepened midlatitude trough. They thus represent the different mechanisms downscaling from large-scale conditions to regional diurnal forcings. After the onset of the first type, the intensified monsoon southerlies at night lead to the northward displacement of large-scale ascent and northward water vapor transport with warm moist energy. The monsoon rainband tends to move to the north of 35°N with a robust response in precipitation systems, especially in the meso-α-scale rain events from midnight to morning. As a comparison, the rainband stays at 30°–35°N after the onset of the second type when the strengthened large-scale ascent and water vapor convergence are located relatively south. These differences between the two types of southerly monsoon surges highlight that the multiday large-scale conditions interact with subdaily regional forcings and greatly regulate the detailed evolution of summer rainband over East Asia. [ABSTRACT FROM AUTHOR]

Successive mesoscale convective systems may develop for several days during the mei-yu season (June–July) over eastern China. They can yield excessive rainfall in a narrow latitudinal band (called a corridor), causing severe floods. The climatology of rainfall corridors and related environmental factors are examined using 20 yr of satellite rainfall and atmospheric data. A total of 93 corridors are observed over eastern China, with maximum occurrence at 27°–31°N. They typically last 2–3 days, but some persist ≥4 days, with an extreme event lasting 11 days. These multiday convective episodes exhibit primary and secondary peaks in the morning and afternoon, respectively, with a diurnal cycle that is in contrast to other afternoon-peak rain events. On average, the corridors occur in ~23% days of the mei-yu season, but they can contribute ~51% of the total rainfall. They also vary with years and explain ~70% of the interannual variance of mei-yu-season rainfall. Composite analyses show that most corridors develop along zonally oriented quasi-stationary mei-yu fronts over central China where monsoon southwesterlies converge with northerly anomalies from the midlatitudes. The monsoon flow accelerates at ~0200 LST and forms a regional wind maximum or low-level jet over South China, which induces moisture flux convergence in morning-peak corridors. The nocturnal acceleration is less evident for afternoon-peak corridors. The mei-yu front and monsoon southwesterlies also influence the corridor's duration, which is regulated by a dipole of geopotential anomalies, with positive in the tropics and negative in the midlatitudes. The dipole expresses a joint influence of the blocking patterns in midlatitudes and the El Niño–related anomalous high over the western Pacific Ocean, and the dipole's intensity explains well the interannual variations of the corridors. [ABSTRACT FROM AUTHOR]

The complex features of rainfall diurnal cycles at the south China coast are examined using hourly rain gauge data and satellite products (CMORPH and TRMM 3B42) during 1998-2014. It is shown that morning rainfall is pronounced near the coasts and windward mountains, with high rainfall in the summer monsoon season, while afternoon rainfall is dominant on land, and nocturnal rainfall occurs at northern inland sites. Both satellite products report less morning rainfall and more afternoon rainfall than the rain gauge data, and they also miss the midnight rainfall minimum. These errors are mainly attributable to an underestimation of morning moderate and intense rains at coasts and an overestimation of afternoon-evening light rains on land. With a correction of the systematic bias, satellite products faithfully resolve the spatial patterns of normalized rainfall diurnal cycles related to land-sea contrast and terrains, suggesting an improved data application for regional climate studies. In particular, they are comparable to the rain gauge data in showing the linear reduction of morning rainfall from coasts to inland regions. TRMM is marginally better than CMORPH in revealing the overall features of diurnal cycles, while higher-resolution CMORPH captures more local details. All three datasets also present that morning rainfall decreases from May-June to July-August, especially on land; it exhibits pronounced interannual variations and a decadal increase in 1998-2008 at coasts. Such long-term variations of morning rainfall are induced by the coastal convergence and mountain liftings of monsoon shear flow interacting with land breeze, which is mainly regulated by monsoon southwesterly winds in the northern part of the South China Sea. [ABSTRACT FROM AUTHOR]

Breathing is a singularly robust behavior, yet this motor pattern is continuously modulated at slow and fast timescales to maintain blood-gas homeostasis, while intercalating orofacial behaviors. This functional multiplexing goes beyond the rhythmogenic function that is typically ascribed to medullary respiration-modulated networks and may explain lack of progress in identifying the mechanism and constituents of the respiratory rhythm generator. By recording optically along the ventral respiratory column in medulla, we found convergent evidence that rhythmogenic function is distributed over a dispersed and heterogeneous network that is synchronized by electrotonic coupling across a neuronal syncytium. First, high-speed recordings revealed that inspiratory onset occurred synchronously along the column and did not emanate from a rhythmogenic core. Second, following synaptic isolation, synchronized stationary rhythmic activity was detected along the column. This activity was attenuated following gap junction blockade and was silenced by tetrodotoxin. The layering of syncytial and synaptic coupling complicates identification of rhythmogenic mechanism, while enabling functional multiplexing. [ABSTRACT FROM AUTHOR]

Breathing is a singularly robust behavior, yet this motor pattern is continuously modulated at slow and fast timescales to maintain blood-gas homeostasis, while intercalating orofacial behaviors. This functional multiplexing goes beyond the rhythmogenic function that is typically ascribed to medullary respiration-modulated networks and may explain lack of progress in identifying the mechanism and constituents of the respiratory rhythm generator. By recording optically along the ventral respiratory column in medulla, we found convergent evidence that rhythmogenic function is distributed over a dispersed and heterogeneous network that is synchronized by electrotonic coupling across a neuronal syncytium. First, high-speed recordings revealed that inspiratory onset occurred synchronously along the column and did not emanate from a rhythmogenic core. Second, following synaptic isolation, synchronized stationary rhythmic activity was detected along the column. This activity was attenuated following gap junction blockade and was silenced by tetrodotoxin. The layering of syncytial and synaptic coupling complicates identification of rhythmogenic mechanism, while enabling functional multiplexing. [ABSTRACT FROM AUTHOR]

Synchronization of inspiratory burst onset along the ventral respiratory column in the neonate mouse is mediated by electrotonic coupling. B Correction: BMC Biol 21, 83 (2023) b B https://doi.org/10.1186/s12915-023-01575-5 b Following publication of the original article [[1]], the authors identified errors in the affiliations of Boris Gourévitch which are corrected as follows: 1) Institut Pasteur, Université Paris Cité, Inserm, Institut de l'Audition, F-75012 Paris, France 2) CNRS, Paris, France The authors also omitted two funding sources which they would like to state ahead: Fondation pour l'Audition FPA-IDA03 (BG). [Extracted from the article]

Background: Silk fibroin hydrogel, derived from Bombyx mori cocoons, has been shown to have potential effects on wound healing due to its excellent biocompatibility and less immunogenic and biodegradable properties. Many studies suggest silk fibroin as a promising material of wound dressing and it can support the adhesion and proliferation of a variety of human cells in vitro. However, lack of translational evidence has hampered its clinical applications for skin repair. Herein, a heparin-immobilized fibroin hydrogel was fabricated to deliver FGF1 (human acidic fibroblast growth factor 1) on top of wound in rats with full-thickness skin excision by performing comprehensive preclinical studies to fully evaluate its safety and effectiveness. The wound-healing efficiency of developed fibroin hydrogels was evaluated in full-thickness wound model of rats, compared with the chitosan used clinically.Results: The water absorption, swelling ratio, accumulative FGF1 releasing rate and biodegradation ratio of fabricated hydrogels were measured. The regenerated fibroin hydrogels with good water uptake properties rapidly swelled to a 17.3-fold maximum swelling behavior over 12 h and a total amount of 40.48 ± 1.28% hydrogels was lost within 15 days. Furthermore, accumulative releasing data suggested that heparinized hydrogels possessed effective release behavior of FGF1. Then full-thickness skin excision was created in rats and left untreated or covered with heparinized fibroin hydrogels-immobilized recombinant human FGF1. The histological evaluation using hematoxylin and eosin (HE) and Masson's trichrome (MT) staining was performed to observe the dermic formation and collagen deposition on the wound-healing site. To evaluate the wound-healing mechanisms induced by fibroin hydrogel treatment, wound-healing scratch and cell proliferation assay were performed. it was found that both fibroin hydrogels and FGF1 can facilitate the migration of fibroblast L929 cells proliferation and migration.Conclusion: This study provides systematic preclinical evidence that the silk fibroin promotes wound healing as a wound-healing dressing, thereby establishing a foundation toward its further application for new treatment options of wound repair and regeneration. [ABSTRACT FROM AUTHOR]