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ABSTRACT To understand the cosmic accretion history of supermassive black holes, separating the radiation from active galactic nuclei (AGNs) and star-forming galaxies (SFGs) is critical. However, a reliable solution on photometrically recognizing AGNs still remains unsolved. In this work, we present a novel AGN recognition method based on Deep Neural Network (Neural Net; NN). The main goals of this work are (i) to test if the AGN recognition problem in the North Ecliptic Pole Wide (NEPW) field could be solved by NN; (ii) to show that NN exhibits an improvement in the performance compared with the traditional, standard spectral energy distribution (SED) fitting method in our testing samples; and (iii) to publicly release a reliable AGN/SFG catalogue to the astronomical community using the best available NEPW data, and propose a better method that helps future researchers plan an advanced NEPW data base. Finally, according to our experimental result, the NN recognition accuracy is around 80.29 per cent–85.15 per cent, with AGN completeness around 85.42 per cent–88.53 per cent and SFG completeness around 81.17 per cent–85.09 per cent.

Lately, carbazole‐based self‐assembled monolayers (SAMs) are widely employed as effective hole‐selective layers (HSLs) in inverted perovskite solar cells (PSCs). Nevertheless, these SAMs tend to aggregate in solvents due to their amphiphilic nature, hindering the formation of a monolayer on the ITO substrate and impeding effective passivation of deep defects in the perovskites. In this study, a series of new SAMs including DPA‐B‐PY, CBZ‐B‐PY, POZ‐B‐PY, POZ‐PY, POZ‐T‐PY, and POZ‐BT‐PY are synthesized, which are employed as interfacial repairers and coated atop CNph SAM to form a robust CNph SAM@pseudo‐planar monolayer as HSL in efficient inverted PSCs. The CNph SAM@pseudo‐planar monolayer strategy enables a well‐aligned interface with perovskites, synergistically promoting perovskite crystal growth, improving charge extraction/transport, and minimizing nonradiative interfacial recombination loss. As a result, the POZ‐BT‐PY‐modified PSC realizes an impressively enhanced solar efficiency of up to 24.45% together with a fill factor of 82.63%. Furthermore, a wide bandgap PSC achieving over 19% efficiency. Upon treatment with the CNph SAM@pseudo‐planar monolayer, also demonstrates a non‐fullerene organic photovoltaics (OPVs) based on the PM6:BTP‐eC9 blend, which achieves an efficiency of 17.07%. Importantly, these modified PSCs and OPVs all show remarkably improved stability under various testing conditions compared to their control counterparts. [ABSTRACT FROM AUTHOR]

Foreign bodies in the kidney have rarely been reported. However, they can be a clinical problem for urologists. We report on a patient with a residual segment of guidewire coating embedded in the renal parenchyma following computed tomography (CT)-guided percutaneous nephrostomy drainage (PCND), and our successful minimally invasive management with retrograde intrarenal surgery (RIRS).

The current bottleneck in the development of efficient photocatalysts for hydrogen evolution is the limited availability of high‐performance acceptor units. Over the past nine years, dibenzo[b,d]thiophene sulfone (DBS) has been the preferred choice for the acceptor unit. Despite extensive exploration of alternative structures as potential replacements for DBS, a superior substitute remains elusive. In this study, a symmetry‐breaking strategy was employed on DBS to develop a novel acceptor unit, BBTT‐1SO. The asymmetric structure of BBTT‐1SO proved beneficial for increasing multiple moment and polarizability. BBTT‐1SO‐containing polymers showed higher efficiencies for hydrogen evolution than their DBS‐containing counterparts by up to 166 %. PBBTT‐1SO exhibited an excellent hydrogen evolution rate (HER) of 222.03 mmol g−1 h−1 and an apparent quantum yield of 27.5 % at 500 nm. Transient spectroscopic studies indicated that the BBTT‐1SO‐based polymers facilitated electron polaron formation, which explains their superior HERs. PBBTT‐1SO also showed 14 % higher HER in natural seawater splitting than that in deionized water splitting. Molecular dynamics simulations highlighted the enhanced water‐PBBTT‐1SO polymer interactions in salt‐containing solutions. This study presents a pioneering example of a substitute acceptor unit for DBS in the construction of high‐performance photocatalysts for hydrogen evolution. [ABSTRACT FROM AUTHOR]

14,14′‐Bidibenzo[a,j]anthracenes (BDBAs) were prepared by iridium‐catalyzed annulation of 5,5′‐biterphenylene with alkynes. The molecular geometries of overcrowded BDBAs were verified by X‐ray crystallography. The two dibenzo[a,j]anthryl moieties are connected through the sterically hindered 14 positions, resulting in highly distorted molecular halves. The conformation with a small twist angle between two molecular halves can minimize steric conflicts between the substituents at 1 and 13 positions and the carbon atoms of the central axis, as well as steric clashes between those substituents. One such example is octafluoro‐substituted BDBA, where the interplanar angle between two anthryl moieties is approximately 31° (currently the lowest reported value, cf. 81° in 9,9′‐bianthracene). The intramolecular interactions and electronic couplings between two molecular halves resulted in upfield 1H NMR signals, redshifted absorption and emission bands, and a reduced HOMO–LUMO gap. Photodynamic investigations on BDBAs indicated that the formation of the conventional symmetry‐breaking charge transfer (SBCT) state was suspended by restricted rocking around the central C−C bond. Such a mechanism associated with this highly constrained conformation was examined for the first time. [ABSTRACT FROM AUTHOR]

Singlet fission (SF) holds great promise for current photovoltaic technologies, where tetracenes, with their relatively high triplet energies, play a major role for application in silicon‐based solar cells. However, the SF efficiencies in tetracene dimers are low due to the unfavorable energetics of their singlet and triplet energy levels. In the solid state, tetracene exhibits high yields of triplet formation through SF, raising great interest about the underlying mechanisms. To address this discrepancy, we designed and prepared a novel molecular system based on a hexaphenylbenzene core decorated with 2 to 6 tetracene chromophores. The spatial arrangement of tetracene units, induced by steric hindrance in the central part, dictates through‐space coupling, making it a relevant model for solid‐state chromophore organization. We then revealed a remarkable increase in SF quantum yield with the number of tetracenes, reaching quantitative (196 %) triplet pair formation in hexamer. We observed a short‐lived correlated triplet pair and limited magnetic effects, indicating ineffective triplet dissociation in these through‐space coupled systems. These findings emphasize the crucial role of the number of chromophores involved and the interchromophore arrangement for the SF efficiency. The insights gained from this study will aid designing more efficient and technology‐compatible SF systems for applications in photovoltaics. [ABSTRACT FROM AUTHOR]

Salmonella, a prevalent foodborne pathogen that causes zoonoses worldwide, comprises 2 species, Salmonella enterica and S. bongori, and [approximately equal to]2,600 serovars (1). In Taiwan, salmonellosis has been primarily caused [...]

A three-degrees-of-freedom model, including surge, sway and yaw motion, with differential thrusters is proposed to describe unmanned surface vehicle (USV) dynamics in this study. The experiment is carried out in the Qing Huai River and the data obtained from different zigzag trajectories are filtered by a Gaussian filtering method. A physics-informed neural network (PINN) is proposed to identify the dynamic models of the USV. PINNs combine the advantages of data-driven machine learning and physical models. They can also embed the speed and steering models into the loss function, which can significantly retain all types of information. Compared with traditional neural networks, the results show that the PINN has better generalization ability in predicting the surge and sway velocities and rotation speed with only limited training data.

Cholera, an acute diarrheal disease caused by the toxigenic Vibrio cholerae serogroup O1 and its derivative serogroup O139, remains a severe public health threat in some regions of the world [...]

A new series of biaryls, bi‐linear‐terphenylenes (BLTPs), were prepared using the tert‐butyllithium‐mediated cyclization as the key synthetic step. The three‐dimensional structures of the studied compounds were verified using X‐ray crystallography and DFT calculations. Tetraaryl(ethynyl)‐substituted BLTPs are highly crowded molecules, and the internal rotation around the central C−C bond is restricted due to a high barrier (>50 kcal/mol). These structures contain several aryl/terphenylenyl/aryl sandwiches, where the through‐space π‐π (TSPP) interactions are strongly reflected in the shielding of 1H NMR chemical shifts, reduction of oxidation potentials, increasing aromaticity of the central six‐membered ring and decreasing antiaromaticity of the four‐membered rings in a terphenylenyl moiety based on NICS(0) and iso‐chemical shielding surfaces. Despite the restricted C−C bond associated intramolecular TSPP interactions for BLTPs in the ground state, to our surprise, the electronic coupling between two linear terphenylenes (LTPs) in BLTPs in the excited state is weak, so that the excited‐state behavior is dominated by the corresponding monomeric LTPs. In other words, all BLTPs undergo ultrafast relaxation dynamics via strong exciton‐vibration coupling, acting as a blue‐light absorber with essentially no emission. [ABSTRACT FROM AUTHOR]

The intractable brittleness and opacity of the crystalline semiconductor restrict the prospect of developing low‐cost imaging systems. Here, infrared visualization technologies are established with large‐area, semi‐transparent organic upconversion devices that bring high‐resolution invisible images into sight without photolithography. To exploit all photoinduced charge carriers, a monolithic device structure is proposed built on the infrared‐selective, single‐component charge generation layer of chloroaluminum phthalocyanine (ClAlPc) coupled to two visible light‐emitting layers manipulated with unipolar charges. Transient pump‐probe spectroscopy reveals that the ClAlPc‐based device exhibits an efficient charge dissociation process under forward bias. This process is indicated by the prompt and strong features of electroabsorption screening. Furthermore, by imposing the electric field, the ultrafast excited state dynamic suggests a prolonged charge carrier lifetime from the ClAlPc, which facilitates the charge utilization for upconversion luminance. For the first time, >30% of the infrared photons are utilized without photomultiplication strategies owing to the trivial spectrum overlap between ClAlPc and the emitter. In addition, the device can broadcast the acoustic signal by synchronizing the device frequency with the light source, which enables to operate it in dual audio‐visual mode. The work demonstrates the potential of upconversion devices for affordable infrared imaging in wearable electronics. [ABSTRACT FROM AUTHOR]

Self‐assembled monolayers (SAMs) offer the advantage of facile interfacial modification, leading to significant improvements in device performance. In this study, we report the design and synthesis of a new series of carboxylic acid‐functionalized porphyrin derivatives, namely AC‐1, AC‐3, and AC‐5, and present, for the first time, a strategy to exploit the large π‐moiety of porphyrins as a backbone for interfacing the indium tin oxide (ITO) electrode and perovskite active layer in an inverted perovskite solar cell (PSC) configuration. The electron‐rich nature of porphyrins facilitates hole transfer and the formation of SAMs, resulting in a dense surface that minimizes defects. Comprehensive spectroscopic and dynamic studies demonstrate that the double‐anchored AC‐3 and AC‐5 enhance SAMs on ITO, passivate the perovskite layer, and function as conduits to facilitate hole transfer, thus significantly boosting the performance of PSCs. The champion inverted PSC employing AC‐5 SAM achieves an impressive solar efficiency of 23.19 % with a high fill factor of 84.05 %. This work presents a novel molecular engineering strategy for functionalizing SAMs to tune the energy levels, molecular dipoles, packing orientations to achieve stable and efficient solar performance. Importantly, our comprehensive investigation has unraveled the associated mechanisms, offering valuable insights for future advancements in PSCs. [ABSTRACT FROM AUTHOR]

Fast radio bursts (FRBs) are mysterious bursts in the millisecond time-scale at radio wavelengths. Currently, there is little understanding about the classification of repeating FRBs, based on difference in physics, which is of great importance in understanding their origin. Recent works from the literature focus on using specific parameters to classify FRBs to draw inferences on the possible physical mechanisms or properties of these FRB subtypes. In this study, we use publicly available 1652 repeating FRBs from FRB 121102 detected with the Five-hundred-metre Aperture Spherical Telescope (FAST), and studied them with an unsupervised machine learning model. By fine-tuning the hyperparameters of the model, we found that there is an indication for four clusters from the bursts of FRB 121102 instead of the two clusters ('Classical' and 'Atypical') suggested in the literature. Wherein, the 'Atypical' cluster can be further classified into three sub-clusters with distinct characteristics. Our findings show that the clustering result we obtained is more comprehensive not only because our study produced results which are consistent with those in the literature but also because our work uses more physical parameters to create these clusters. Overall, our methods and analyses produced a more holistic approach in clustering the repeating FRBs of FRB 121102. [ABSTRACT FROM AUTHOR]

Fast radio bursts (FRBs) are astronomical transients with millisecond time-scales. Although most of the FRBs are not observed to repeat, a few of them are detected to repeat more than hundreds of times. There exist a large variety of physical properties among these bursts, suggesting heterogeneous mechanisms of FRBs. In this paper, we conduct a categorization on the extremely frequently repeating FRB 20201124A with the assistance of machine learning, as such techniques have the potential to use subtle differences and correlations that humans are unaware of to better classify bursts. The research is carried out by applying the unsupervised Uniform Manifold Approximation and Projection (umap) model on the FRB 20201124A data provided by Five-hundred-meter Aperture Spherical radio Telescope. The algorithm eventually categorizes the bursts into three clusters. In addition to the two categories in previous work based on waiting time, a new way for categorization has been found. The three clusters are either high energy, high frequency, or low frequency, reflecting the distribution of FRB energy and frequency. Importantly, a similar machine learning result is found in another frequently repeating FRB 20121102A, implying a common mechanism among this kind of FRB. This work is one of the first steps towards the systematical categorization of the extremely frequently repeating FRBs. [ABSTRACT FROM AUTHOR]

We report a surprisingly infrared (MIR) pulse generation in simultaneous interplay of intra-pulse self-phase-modulation and dispersion. broadband and efficient middle-LiGaS2 (LGS) by invoking a difference frequency generation,

The exploration of deactivation mechanisms for near‐infrared(NIR)‐emissive organic molecules has been a key issue in chemistry, materials science and molecular biology. In this study, based on transient absorption spectroscopy and transient grating photoluminescence spectroscopy, we demonstrate that the aggregated PtII complex 4H (efficient NIR emitter) exhibits collective out‐of‐plane motions with a frequency of 32 cm−1 (0.96 THz) in the excited states. Importantly, similar THz characteristics were also observed in analogous PtII complexes with prominent NIR emission efficiency. The conservation of THz motions enables excited‐state deactivation to proceed along low‐frequency vibrational coordinates, contributing to the suppression of nonradiative decay and remarkable NIR emission. These novel results highlight the significance of excited‐state vibrations in nonradiative processes, which serve as a benchmark for improving device performance. [ABSTRACT FROM AUTHOR]

Although vacuum‐deposited metal halide perovskite light‐emitting diodes (PeLEDs) have great promise for use in large‐area high‐color‐gamut displays, the efficiency of vacuum‐sublimed PeLEDs currently lags that of solution‐processed counterparts. In this study, highly efficient vacuum‐deposited PeLEDs are prepared through a process of optimizing the stoichiometric ratio of the sublimed precursors under high vacuum and incorporating ultrathin under‐ and upper‐layers for the perovskite emission layer (EML). In contrast to the situation in most vacuum‐deposited organic light‐emitting devices, the properties of these perovskite EMLs are highly influenced by the presence and nature of the upper‐ and presublimed materials, thereby allowing us to enhance the performance of the resulting devices. By eliminating Pb° formation and passivating defects in the perovskite EMLs, the PeLEDs achieve an outstanding external quantum efficiency (EQE) of 10.9% when applying a very smooth and flat geometry; it reaches an extraordinarily high value of 21.1% when integrating a light out‐coupling structure, breaking through the 10% EQE milestone of vacuum‐deposited PeLEDs. [ABSTRACT FROM AUTHOR]

The Hubble constant (H 0) is a measurement to describe the expansion rate of the Universe in the current era. However, there is a 4.4σ discrepancy between the measurements from the early Universe and the late Universe. In this research, we propose a model-free and distance-free method to constrain H 0. Combining Friedman–Lemaître–Robertson–Walker cosmology with geometrical relation of the proper motion of extragalactic jets, the lower limit (H 0,min) of H 0 can be determined using only three cosmology-free observables: the redshifts of the host galaxies, and the approaching and receding angular velocities of radio jets. Using these, we propose to use the Kolmogorov–Smirnov test (K–S test) between cumulative distribution functions of H 0,min to differentiate cosmology. We simulate 100, 200, and 500 extragalactic jets with three levels of accuracy of the proper motion (μa and μr), at 10, 5, and 1 per cent, corresponding to the accuracies of the current and future radio interferometers. We perform K–S tests between the simulated samples as theoretical distributions with different H 0 and power-law index of velocity distribution of jets and mock observational data. Our result suggests increasing sample sizes leads to tighter constraints on both power-law index and the Hubble constant at moderate accuracy (i.e. |$10$| and |$5{{\ \rm per\ cent}}$|⁠), while at |$1{{\ \rm per\ cent}}$| accuracy, increasing sample sizes leads to tighter constraints on power-law index more. Improving accuracy results in better constraints in the Hubble constant compared with the power-law index in all cases, but it alleviates the degeneracy. [ABSTRACT FROM AUTHOR]

Ultrashort light pulses are ubiquitous in modern research but the electromagnetic field of the optical cycles is usually not easy to obtain as a function of time. Field‐resolved pulse characterization requires either a nonlinear‐optical process or auxiliary sampling pulses that are shorter than the waveform under investigation and pulse metrology without at least one of these two prerequisites is often thought to be impossible. Here is reported how the optical field cycles of laser pulses can be characterized with field‐linear sensitivity and no ultrashort probe events. A free‐space electron beam is let to cross with the waveform of interest. Randomly arriving electrons interact by means of their elementary charge with the optical waveform in a linear‐optical way and reveal the optical cycles as the turning points in a time‐integrated deflection histogram. The sensitivity is only limited by the electron‐beam emittance and can reach the level of thermal radiation and vacuum fluctuations. Besides overturning a common belief in optical pulse metrology, the idea also provides practical perspectives for in situ characterization and optimization of optical waveforms in higher‐harmonics experiments, ultrafast transmission electron microscopes, laser‐driven particle accelerators, free‐electron lasers, or generally any experiments with waveform‐controlled laser pulses in a vacuum environment. [ABSTRACT FROM AUTHOR]

Objective: There is a great interest in determining whether the expression of the programmed cell death ligand 1 is correlated with the efficacy of immune checkpoint inhibitors in patients with clear cell renal cell carcinoma; however, primary tumor biopsies can only provide limited information. Therefore, we explored the expression of programmed cell death ligand 1 on circulating tumor cells, which is a potential predictor of therapeutic response. Methods: Circulating tumor cells were isolated from 20 clear cell renal cell carcinoma patients based on cell surface markers targeting clear cell renal cell carcinoma using IsoFlux device, followed by identification according to cell morphology and immunofluorescence studies. Programmed cell death ligand 1 expression status and clinical correlations were also analyzed. Results: Before treatment with programmed cell death protein 1 inhibitors, circulating tumor cells were detected in all patients, ranging from 1 to 22 (median 7), with 75% (15/20) of the patients having programmed cell death ligand 1 + circulating tumor cells. Circulating tumor cell programmed cell death ligand 1 expression did not correlate with the immunohistochemical staining of programmed cell death ligand 1 in primary tumors. During treatment with programmed cell death protein 1 inhibitors, the disease control rate was much higher in the patients harboring programmed cell death ligand 1 + circulating tumor cells (73%, 11/15) than others (20%, 1/5). We also found that changes in total circulating tumor cell numbers and programmed cell death ligand 1 + circulating tumor cell counts correlated well with the disease outcome. Conclusion: We showed that the presence of programmed cell death ligand 1 + circulating tumor cells before programmed cell death protein 1 inhibition treatment could be a prognosis predictive factor and that the dynamic changes in circulating tumor cell numbers may be used to monitor the therapeutic response. Our study confirms the possibility of programmed cell death ligand 1 + circulating tumor cell detection in clear cell renal cell carcinoma patients' blood samples, which can potentially be used as an individualized immunotherapy molecular biomarker for real‐time exploration. [ABSTRACT FROM AUTHOR]

Hem-o-lok clips are widely used in robotic-assisted radical prostatectomy (RARP). However, clips-related complications have been reported, including intravesical migration. Here, we share a 60-year-old male case with newly diagnosed prostatic adenocarcinoma. With an unfavorable intermediate risk, he was admitted for RARP. He was discharged from hospital without any immediate complications. However, he reported progressive dysuria and slow urine stream 6 months after surgery. Cystoscopy showed severe bladder neck contracture (BNC), and 2 Hem-o-lok clips were found intravesically and removed during bladder neck incision. Subsequently, fiberocystoscopy revealed another 2 clips near the bladder neck with mild BNC after another 6 months. These 2 clips were also removed during bladder neck dilatation. His urination status then improved without further obstruction. Clip migration after RARP is uncommon; however, clinicians must keep this in mind when patients present with new complaints such as lower urinary tract symptoms, hematuria, and recurrent urinary tract infections. [ABSTRACT FROM AUTHOR]