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An effective crop yield prediction is critical for making precise nitrogen (N) management decisions. A multi-site-year study was conducted across eastern Canada with the objectives to (1) construct machine-learning random forest regression (RFR) models for canola yield prediction; and (2) develop site-specific N recommendations using the RFR modelling approach. Soil characteristics, weather, plant growth and spectral index data collected from 2013 to 2015 were used to train the RFR models and the 2016 data for model validation in terms of making N decisions. Results showed that canola yields responded positively to N application rates in 16 out of the 18 site-year environments, with sometimes higher yields and an average of 8% higher N use efficiency for the split-N strategy than for the same amount of N applied only at preplant. Heat stress and precipitation distribution were identified as of critical importance in total yield variation. The RFR model by combining weather, soil and plant growth features with the spectral indices displayed highly improved prediction reliability, up to 85%, with 53–57% lower root mean square errors, compared with the model based only on leaf chlorophyll or normalized difference vegetation index. Based on the RFR algorithm, an average economic optimum N rate of 150 kg N ha−1 was recommended for most canola production scenarios in the test year. This study demonstrated that the machine learning-based RFR modelling approach can be used to implement optimal nutrient management strategies for sustainable crop production, which is sensitive and better adapted to environment-induced abiotic stresses.

In this study, we present a wavelength sensor that is capable of distinguishing the spectrum in the range from ultraviolet (UV) to near-infrared (NIR) light. The filterless device is composed of two horizontally stacking PdSe2/20 μm Si/PdSe2 heterojunction photodetectors with a photovoltaic (PV) behavior, which makes it possible for the device to work at 0 bias voltage. Due to the relatively small thickness of Si and the wavelength-dependent absorption coefficient, the two PdSe2/20 μm Si/PdSe2 photodetectors according to theoretical simulation display a sharp contrast in distribution of the photoabsorption rate. As a result, the photocurrents of both photodetectors evolve in completely different ways with increasing wavelengths, leading to a monotonic decrease in the photocurrent ratio from 6800 to 22 when the wavelength gradually increases from 265 to 1050 nm. The corresponding relationship between both the photocurrent ratio and wavelength can be easily described by the monotonic function, which can help to precisely determine the wavelength in the range from 265 to 1050 nm, with an average relative error less than ±1.6%. It is also revealed that by slightly revising the monotonic function, the wavelength in other different temperatures can also be estimated.

Palladium diselenide (PdSe2), a noble transition metal dichalcogenide has attracted increasing attention in recent years due to its outstanding semiconductor properties. In this study, 2D PdSe2 nanofilms with thicknesses ranging from 2 to 28 nm and their heterostructures with Si substrates (PdSe2/Si heterostructures) were synthesized via a simple selenization method. Electrical transport characterizations based on field-effect transistor devices indicate that the few-layer PdSe2 nanofilms exhibit a p-type semiconducting behavior. The optimal sensing performance of the PdSe2/Si-8 sensor (8 nm-thick PdSe2) exhibits a comparable response toward NO2 gas (ΔR/Ra = ∼7.2% to 100 ppb and ∼18% to 1 ppm) at room temperature (RT). This response may result from the heterostructure effect and maze-type surface. Additionally, the PdSe2/Si-8 sensor has selectivity toward NO2 compared with other gases including NO, H2, CO, NH3, and C2H5OH. Furthermore, density functional theory (DFT) calculations reveal the largest adsorption energy and charge transfer between NO2 and the PdSe2 surface, which coincides well with the experimental results. Moreover, the PdSe2/Si-8 sensor also exhibits repeatability and long-term stability during about 4 months at RT. These results indicate that the PdSe2/Si heterostructures may be a promising nanomaterial for room-temperature NO2 gas-sensing devices.

In this letter, we demonstrate the fabrication of a conformal CuO/Si microholes array heterojunction through the DC reactive magnetron sputtering from a high-purity Cu target. By using the monolayer graphene as the top electrode, the device served well as a self-powered vis -NIR photodetector, showing a high responsivity of 301.5 mA W−1, specific detectivity of $7.96\times 10^{12}$ Jones and a fast response speed (rise time $9.9~\mu $ s and fall time $10~\mu \text{s}$ ) upon 530 nm illumination. Compared to its planar counterpart, the responsivity was remarkably enhanced over the broadband region. The underlying reason should be ascribed to the improved light trapping in the microholes via the longitudinal Fabry-Perot (F-P) cavity resonance, according to theoretical simulation by finite-difference time-domain (FDTD) solution. Such an effect gave rise to an enhanced light-matter interaction, leading to the improved photoresponse. This work also opens up an effective way for the on-chip high performance photodetection due to the well compatibility with the current complementary metal-oxide-semiconductor (CMOS) technology.

Severe extracranial carotid stenosis (SECS) patients may present with nonspecific neurological symptoms that require intracranial magnetic resonance imaging (MRI) and time-of-flight (TOF)-MR angiography (MRA) to exclude intracranial pathology. Recognition of SECS on intracranial TOF-MRA findings is beneficial to provide a prompt carotid imaging study and aggressive stroke prevention. Patients with SECS (January 2016 to May 2019) undergoing percutaneous transluminal angioplasty and stenting (PTAS) were included. Differences in normalized signal intensities (SRICA) and diameters (DICA) between bilateral petrous internal carotid arteries (ICAs) were calculated 1 cm from the orifice. A hypothesized criterion describing the opacification grades (GOPH) of bilateral ophthalmic arteries was proposed. We correlated SRICA (p = 0.041), DICA (p = 0.001) and GOPH (p = 0.012), with the severity of extracranial carotid stenosis on digital subtractive angiography (DSA) in the examined group (n = 113), and all showed statistical significance in predicting percentages of ICA stenosis. The results were further validated in another patient group with SECS after radiation therapy (n = 20; p = 0.704 between the actual and predicted stenosis grades). Our findings support the evaluation of the signal ratio and diameter of intracranial ICA on TOF-MRA to achieve early diagnosis and provide appropriate management of SECS.

Solar-blind deep-ultraviolet (DUV) photodetectors based on Ga2O3 have attracted great attention due to their potential applications for many military and civil purposes. However, the development of device integration for optoelectronic system applications remains a huge challenge. Herein, we report a facile method for patterned-growth of high-quality β-Ga2O3 thin films, which are assembled into a photodetectors array comprising 8 × 8 device units. A representative detector exhibits outstanding photoresponse performance, in terms of an ultra-low dark current of ∼0.62 pA, a large Ilight/Idark ratio exceeding 104, a high responsivity of ∼0.72 A W−1 and a decent specific detectivity of ∼4.18 × 1011 Jones, upon 265 nm DUV illumination. What is more, the DUV/visible (250/400 nm) rejection ratio is as high as 103 with a sharp response cut-off wavelength at ∼280 nm. Further optoelectronic analysis reveals that the photodetectors array has good uniformity and repeatability, endowing it the capability to serve as a reliable DUV light image sensor with a decent spatial resolution. These results suggest that the proposed technique offers an effective avenue for patterned growth of β-Ga2O3 thin films for multifunctional DUV optoelectronic applications.

Highly ordered perovskite nanowire (PNW) arrays are important building blocks for potential application in integrated optoelectronic devices due to their unique properties. Herein, a recordable digital versatile disk-assisted nanochannel-confined growth (NCG) strategy was developed for large-scale growth of different kinds of PNW arrays with preferentially crystallographic orientation on various substrates. Photodetector constructed from MAPbI3 NW arrays exhibits prominent photoresponse properties with a responsivity of 20.56 A W−1 and specific detectivity of 4.73 × 1012 Jones, respectively. What is more, the photodetector can function as a polarization-sensitive photodetector due to the crystallographic orientation of the one-dimensional PNW arrays, with a polarization ratio of 2.2. The proposed NCG strategy provides a cost-efficient and effective method for the fabrication of high-quality PNW arrays with potential applications in future integrated devices and systems.

Patterned growth of periodic perovskite film arrays is essential for application in sensing devices and integrated optoelectronic systems. Herein, we report on patterned growth of addressable perovskite photodetector arrays through an uncured polydimethylsiloxane (PDMS) oligomer-assisted solution-processed approach, in which a periodic hydrophilic/hydrophobic substrate replicating the predesigned patterns of the PDMS stamp was formed due to the migration of uncured siloxane oligomers in the PDMS stamp to the intimately contacted substrate. By using this technique, MAPbI3 film photodetector arrays with neglectable pixel-to-pixel variation, a responsivity of 2.83 A W-1, specific detectivity of 5.4 × 1012 Jones, and fast response speed of 52.7/57.1 μs (response/recovery time) were achieved. An 8 × 8 addressable photodetector array was further fabricated, which functioned well as a real-time image sensor with reasonable spatial resolution. It is believed that the proposed strategy will find potential application in large-scale fabrication of other photodetector arrays, which might be potentially important for future integrated optoelectronic devices.

BACKGROUND Aortic dissection is a rare but severe complication of percutaneous transluminal angioplasty and stenting (PTAS) for stenosis of the subclavian artery (SA). This retrospective study was designed to evaluate the risk factors and outcomes of patients with severe stenosis of the SA who underwent PTAS complicated by aortic dissection. METHODS Between 1999 and 2018, 169 cases of severe symptomatic stenosis of the SA underwent PTAS at our institute. Of them, six cases complicated by aortic dissection were included in this study. We evaluated the demographic features, technical factors of PTAS, and clinical outcomes in these six patients. RESULTS Aortic dissection occurred in 5.3% (6/113) of all left SA stenting cases but in none of the right SA stenting cases. All patients had hypertension and a high severity of SA stenosis (85.0 ± 13.0%, 60%-95%). Five of the six patients received balloon-expandable stents (83.3%). All patients had spontaneous resolution of the aortic dissection with conservative treatment. In a 63.33 ± 33.07 (7-118) month follow-up, five of the six patients (83.3%) had long-term symptom relief and stent patency. CONCLUSION Aortic dissection occurred in patients who underwent PTAS for severe stenosis of the left SA, mainly with balloon-expandable stents. We suggest using self-expandable stents and angioplasty with an undersized balloon during PTAS for severe stenosis of the left proximal SA to prevent aortic dissection.

Two-dimensional layered (2D) materials are currently attracting intensive research interest for high-performance photodetection and other optoelectronic applications. However, the study of device integration for multifunctional optoelectronic applications is still at a nascent stage. Here, the assembly of a multilayered PtSe2/pyramid-Si heterostructure-based photodetector array consisting of 8 × 8 device units is demonstrated. Owing to the pronounced light confinement effect of the heterostructures, the devices present an prominent photovoltaic effect, which enables efficient self-driven photodetection in a broadband wavelength spectrum. The Ilight/Idark ratio, responsivity, external quantum efficiency (EQE) and specific detectivity can attain values as high as 5.51 × 106, 567 mA W−1, 87% and 1.26 × 1013 jones, respectively, upon 810 nm near-infrared (NIR) light illumination. What is more, benefiting from the large-scale homogeneous material growth technique, the photodetector array exhibits excellent uniformity and repeatability in photoresponse performance with negligible unit-to-unit variation. The above characteristics provide the photodetector array with the capability of recording a simple image produced by NIR illumination and monitoring a moving photonic signal, showing the great possibility for NIR image sensing and light trajectory tracking applications.

A wavelength sensor as a representative optoelectronic device plays an important role in many fields including visible light communication, medical diagnosis, and image recognition. In this study, a wavelength-sensitive detector with a new operation mechanism was reported. The as-proposed wavelength sensor which is composed of two parallel PtSe2/thin Si Schottky junction photodetectors is capable of distinguishing wavelength in the range from ultraviolet to near infrared (UV-NIR) light (265 to 1050 nm), in that the relationship between the photocurrent ratio of both photodetectors and incident wavelength can be numerically described by a monotonic function. The unique operation mechanism of the thin Si based wavelength sensor was unveiled by theoretical simulation based on Synopsys Sentaurus Technology Computer Aided Design (TCAD). Remarkably, the wavelength sensor has an average absolute error of ±4.05 nm and an average relative error less than ±0.56%, which are much better than previously reported devices. What is more, extensive analysis was performed to reveal how and to what extent the working temperature and incident light intensity, and the thickness of the PtSe2 layer will influence the performance of the wavelength sensor.

Spoken multiple-choice question answering (SMCQA) requires machines to select the correct choice to answer the question by referring to the passage, where the passage, the question, and multiple choices are all in the form of speech. While the audio could contain useful cues for SMCQA, usually only the auto-transcribed text is utilized in model development. Thanks to the large-scaled pre-trained language representation models, such as the bidirectional encoder representations from Transformers (BERT), systems with only auto-transcribed text can still achieve a certain level of performance. However, previous studies have evidenced that acoustic-level statistics can offset text inaccuracies caused by the automatic speech recognition systems or representation inadequacy lurking in word embedding generators, thereby making the SMCQA system robust. Along the line of research, in this study, an audio-aware SMCQA framework is proposed. Two different mechanisms are introduced to distill the useful cues from speech, and then a BERT-based SMCQA framework is presented. In other words, the proposed SMCQA framework not only inherits the advantages of contextualized language representations learned by BERT but integrates the complementary acoustic-level information distilled from audio with the text-level information. A series of experiments demonstrates remarkable improvements in accuracy over selected baselines and SOTA systems on a published Chinese SMCQA dataset.

In this work, we present the construction of a multilayered PtSe2/Ge heterostructure-based photodetector array comprising 1 × 10 device units operating in the short-wavelength infrared (SWIR) spectrum region. The as-fabricated heterostructures show an obvious photovoltaic effect, providing the devices with the ability to work as self-driven photodetectors. Upon 1550 nm illumination, a typical photodetector exhibits prominent photoresponse performance with the current on/off ratio, responsivity, external quantum efficiency and specific detectivity reaching 1.08 × 103, 766 mA W−1, 61.3% and 1.1 × 1011 Jones, respectively. The device also has a fast response speed with rise/fall times of 54.9 μs/56.6 μs. Thanks to the respectable homogeneity in device performance, the photodetector array can reliably record an image of a “diode symbol” produced by SWIR irradiation. What is more, the photodetector is successfully integrated into a SWIR optical communication system serving as an optical receiver to transmit a text signal. The above results imply a huge possibility of the present heterostructure-based photodetector array for some optoelectronic purposes such as SWIR image sensing and optical communication applications.

Multispectral photodetection has garnered enormous research interest and has always been challenging to date. Here, we present the realization of an electrically adjusted single-band/dual-band photodetector based on an inorganic lead-free halide Cs3Cu2I5/two-dimensional (2D) PdTe2 multilayer/Ge multiheterostructure. Owing to its unique optical property and distinct carrier transport behaviour, the device can be easily converted from a single-band photodetector operating in the near-infrared (NIR) region to a dual-band photodetector working in both deep-ultraviolet (DUV) and NIR regimes, upon applying a reverse bias voltage. Significantly, the device shows a peak responsivity of ∼694.1 mA W−1 at 1550 nm at zero bias, and maximum responsivity values of ∼744.2 mA W−1 and ∼712.5 mA W−1 at 265 nm and 1550 nm, respectively, at a small reverse bias. This characteristic also endows the photodetector with an excellent DUV/NIR dual-band optical imaging capability. This work will offer a new opportunity for designing high-performance photodetectors with multiple functionalities operating in complicated circumstances.

We present the first report of a water-regulated method for obtaining a cubic-phase CsPbBr3 single crystal that could be frozen at low temperature with a CsBr/PbBr2 ratio of 1 : 1. The cubic CsPbBr3 single-crystal photodetector exhibits a superior responsivity of 278 A W−1, an EQE of 6.63 × 104%, and an ultrahigh detectivity of 4.36 × 1013 Jones under low-power 520 nm irradiation at 3 V.

In this study, we have developed a high-sensitivity, near-infrared photodetector based on PdSe2/GaAs heterojunction, which was made by transferring a multilayered PdSe2 film onto a planar GaAs. The as-fabricated PdSe2/GaAs heterojunction device exhibited obvious photovoltaic behavior to 808 nm illumination, indicating that the near-infrared photodetector can be used as a self-driven device without external power supply. Further device analysis showed that the hybrid heterojunction exhibited a high on/off ratio of 1.16×105 measured at 808 nm under zero bias voltage. The responsivity and specific detectivity of photodetector were estimated to be 171.34 mA/W and 2.36×1011 Jones, respectively. Moreover, the device showed excellent stability and reliable repeatability. After 2 months, the photoelectric characteristics of the near-infrared photodetector hardly degrade in air, attributable to the good stability of the PdSe2. Finally, the PdSe2/GaAs-based heterojunction device can also function as a near-infrared light sensor.

Platinum telluride (PtTe2) has garnered significant research enthusiasm owing to its unique characteristics. However, large-scale synthesis of PtTe2 toward potential photoelectric and photovoltaic application has not been explored yet. Herein, we report direct tellurization of Pt nanofilms to synthesize large-area PtTe2 films and the influence of growth conditions on the morphology of PtTe2. Electrical analysis reveals that the as-grown PtTe2 films exhibit typical semimetallic behavior, which is in agreement with the results of first-principles density functional theory (DFT) simulation. Moreover, the combination of multilayered PtTe2 and Si results in the formation of a PtTe2/Si heterojunction, exhibiting an obvious rectifying effect. Moreover, the PtTe2-based photodetector displays a broadband photoresponse to incident radiation in the range of 200-1650 nm, with the maximum photoresponse at a wavelength of ∼980 nm. The R and D* of the PtTe2-based photodetector are found to be 0.406 A W-1 and 3.62 × 1012 Jones, respectively. In addition, the external quantum efficiency is as high as 32.1%. On the other hand, the response time of τrise and τfall is estimated to be 7.51 and 36.7 μs, respectively. Finally, an image sensor composed of a 8 × 8 PtTe2-based photodetector array was fabricated, which can record five near-infrared (NIR) images under 980 nm with a satisfying resolution. The result demonstrates that the as-prepared PtTe2 material will be useful for application in NIR optoelectronics.

BACKGROUND Stent patency after carotid angioplasty and stenting (CAS) correlates not only with stroke prevention but also with improvements in cognition and quality of life by positively influencing cerebral perfusion. The long-term outcomes of CAS after more than 5 years have still not been well described. This retrospective study was designed to evaluate the stent patency and significant restenosis (SR) after CAS with more than 5 years of follow-up. METHODS Between 2006 and 2012, 118 patients with carotid stenosis who underwent 131 CAS procedures with regular annual imaging follow-up for more than 5 years were enrolled. We evaluated their demographic characteristics and the risk factors related to stent restenosis. Patients with SR (restenosis ≥ 50%) were compared with those with no significant restenosis (NSR, patency or restenosis < 50%) to identify the restenosis predictors and restenosis-free survival. RESULTS Of the 131 CAS procedures, 16.0% (21/131) had SR. A history of head and neck radiotherapy (HNRT) was a predictor for SR (HR, 6.352; 95% CI, 2.504-16.112; p < 0.001) and was associated with shorter restenosis-free survival (log-rank test p value < 0.001, median time of restenosis-free survival was 38 months). Left-sided stenting was an associated factor for SR (HR, 3.007; 95% CI, 1.068-8.467; p = 0.037) with a trend of less restenosis-free survival (log-rank test p value 0.067). CONCLUSION Both HNRT and left-sided carotid stenosis were predictors of SR after CAS in more than 5 years of long-term follow-up. Restenosis-free survival was significantly shorter in patients with prior HNRT than in patients without previous irradiation treatment. We suggest close follow-up and aggressive medical treatment for patients with prior HNRT and left-sided carotid stenosis undergoing CAS.

Photodetection at a wavelength of about 1060 nm is very important for applications including medical imaging, optical communication, and light detection and ranging. In this article, a self-powered near-infrared light detector with a narrowband at around 1060 nm is realized based on a simple Si Schottky structure, in which the Ohmic and Schottky electrodes are configured on the front and rear surfaces of the Si substrate, respectively. The as-assembled device exhibits a tunable peak response near 1060 nm with a full width at half maximum of 107 nm, which could be due to the combined effect of the narrow photo-current generation and the self-filtering effect of the silicon substrate. At zero bias, a specific detectivity of $\sim 1\times 10^{11}$ Jones and linear dynamic range about 101 dB are achieved, in spite of the weak absorption of Si at this wavelength. The external quantum efficiency can be improved to 135% under a low bias of −1 V, indicating the existence of gain mechanism during photodetection. Finally, it is also found that the as-assembled near-infrared device shows excellent antiinterference capability during the photodetection process. These results corroborate that the present Si photodetector may find promising application in future near-infrared optoelectronic devices and systems.

Lead halide perovskites have received much attention in the field of optoelectronic devices. However, the environment-unfriendly nature and intrinsic instability of these perovskites hamper their commercial applications. In this work, one novel one-dimensional lead-free halide perovskite with high stability, CsCu2I3, was prepared via an antisolvent-assisted crystallization method. The prepared CsCu2I3 bears a high exciton binding energy of ∼105 meV and a high photoluminescence quantum yield of 12.3%. We fabricated a deep ultraviolet photodetector based on a CsCu2I3 film that is nearly blind to 405 nm visible light but is sensitive to 265 and 365 nm illumination. The device exhibits excellent reproducibility and a high Ilight/Idark ratio of 22 under 265 nm illumination. Furthermore, the responsivity, specific detectivity, and external quantum efficiency are as high as 22.1 mA/W, 1.2 × 1011 Jones, and 10.3% under a light density of 0.305 mW/cm2, respectively. These findings demonstrate that CsCu2I3 perovskites should have great potential for future optoelectronics.

OBJECTIVEAssessments of hemorrhage risk based on angioarchitecture have yielded inconsistent results, and quantitative hemodynamic studies have been limited to small numbers of patients. The authors examined whether cerebral hemodynamic analysis using quantitative digital subtraction angiography (QDSA) can outperform conventional DSA angioarchitecture analysis in evaluating the risk of hemorrhage associated with supratentorial arteriovenous malformations (AVMs).METHODSA cross-sectional study was performed by retrospectively reviewing adult supratentorial AVM patients who had undergone both DSA and MRI studies between 2011 and 2017. Angioarchitecture characteristics, DSA parameters, age, sex, and nidus volume were analyzed using univariate and multivariate logistic regression, and QDSA software analysis was performed on DSA images. Based on the QDSA analysis, a stasis index, defined as the inflow gradient divided by the absolute value of the outflow gradient, was determined. The receiver operating characteristic (ROC) curve was used to compare diagnostic performances of conventional DSA angioarchitecture analysis and analysis using hemodynamic parameters based on QDSA.RESULTSA total of 119 supratentorial AVM patients were included. After adjustment for age at diagnosis, sex, and nidus volume, the exclusive deep venous drainage (p < 0.01), observed through conventional angioarchitecture examination using DSA, and the stasis index of the most dominant drainage vein (p = 0.02), measured with QDSA hemodynamic analysis, were independent risk factors for hemorrhage. The areas under the ROC curves for the conventional DSA method (0.75) and QDSA hemodynamics analysis (0.73) were similar. A venous stasis index greater than 2.18 discriminated the hemorrhage group with a sensitivity of 52.6% and a specificity of 81.5%.CONCLUSIONSIn QDSA, a higher stasis index of the most dominant drainage vein is an objective warning sign associated with supratentorial AVM rupture. Risk assessments of AVMs using QDSA and conventional DSA angioarchitecture were equivalent. Because QDSA is a complementary noninvasive approach without extra radiation or contrast media, comprehensive hemorrhagic risk assessment of cerebral AVMs should include both DSA angioarchitecture and QDSA analyses.

Photonic detection with narrow spectrum selectivity is very important to eliminate the signal from obtrusive light, which can improve the anti-interference ability of the infrared imaging system. While the self-driving effect inherent to the p-n junction is very attractive in optic-electronic integration, the application of the p-n junction in narrow-band photodetectors is limited by the usual broad absorption range. In this work, a self-powered filterless narrowband near-infrared photodetector based on CuGaTe2/silicon p-n junction was reported. The as-fabricated photodetector exhibited typical narrow-band response which shall be ascribed to the slightly smaller band gap of Si than CuGaTe2 and the restricted photocurrent generation region in the p-n heterojunction by optimizing CuGaTe2 thickness. It is observed that when the thickness of CuGaTe2 film is 143 nm, the device exhibits a response peak centered around 1050 nm with a full-width at half-maximum of ∼118 nm. Further device analysis reveals a specific detectivity of ∼1012 Jones and a responsivity of 114 mA/W under 1064 nm illumination at zero bias. It was also found that an image system based on the narrowband CuGaTe2/Si photodetector showed high noise immunity for its spectral selective characteristics.

Endovascular coil embolization is an important method for managing intracranial aneurysms. However, aneurysm coiling may fail or be insufficient in geographically difficult aneurysms. A flow-diverter stent (FDS) is an alternative in these difficult coiling aneurysms. Thus, this study reports the experience and outcome of FDS management of intracranial aneurysms.Over 29 months, FDS treated 125 patients with 163 intracranial unruptured aneurysms. This study enrolled 31 men and 94 women, ranging from 17 to 81 years (mean, 58 years). Clinical data, aneurysm characteristics, and angiographic and clinical outcomes of patients treated by FDS were retrospectively assessed.The current study found 151 (93%) aneurysms in the internal carotid artery. Most aneurysms (n = 118; 72%) were small (7 mm). The mean aneurysm size was 6.2 mm (range, 2-38 mm). Follow-up angiography was available in 53 patients with 74 aneurysms (mean, 13 months). Successful FDS deployment in an ideal position was found in 125 of 130 patients (96%). Complete obliteration (CO) was achieved in 58 aneurysms (78%) in the mean 13-month angiographic follow-up. Smaller aneurysms (7 mm) had a CO tendency than larger aneurysms (p0.01) in midterm follow-up. Seven patients (5.6%) had intraprocedural complications (in-stent thrombosis, three patients; distal embolic, two patients; iatrogenic carotid-cavernous fistula, and subarachnoid hemorrhage, one patient). Two patients (1.6%) suffered from permanent procedure-related morbidity (n = 1) or mortality (n = 1). No late hemorrhagic events or stent displacement occurred during the follow-up period.Despite few procedural complications and some pieces of evidence of insufficient aneurismal treatment in a midterm angiographic follow-up, FDS was effective and safe in managing intracranial unruptured aneurysms, particularly in smaller aneurysms, which had better CO than larger ones.

Ultraviolet photodetectors (UVPDs) based on wide band gap semiconductors (WBSs) are important for various civil and military applications. However, the relatively harsh preparation conditions and the high cost are unfavorable for commercialization. In this work, we proposed a non-WBS UVPD by using a silicon nanowire (SiNW) array with a diameter of 45 nm as building blocks. Device analysis revealed that the small diameter SiNW array covered with monolayer graphene was sensitive to UV light but insensitive to both visible and infrared light illumination, with a typical rejection ratio of 25. Specifically, the responsivity, specific detectivity, and external quantum efficiency under 365 nm illumination were estimated to be 0.151 A/W, 1.37 × 1012 Jones, and 62%, respectively, which are comparable to or even better than other WBS UVPDs. Such an abnormal photoelectrical characteristic is related to the HE1m leaky mode resonance (LMR), which is able to shift the peak absorption spectrum from near-infrared to UV regions. It is also revealed that this LMR is highly dependent on the diameter and the period of the SiNW array. These results show narrow band gap semiconductor nanostructures as promising building blocks for the assembly of sensitive UV photodetectors, which are very important for various optoelectronic devices and systems.

GaSe microbelts were successfully synthesized using Ga/Ga2Se3 as the precursor mixture, where excess Ga was required to serve as the metal catalyst. Meanwhile, a spontaneously oxidized surface amorphous oxide (GaOx) layer formed, which induced a built-in electric field perpendicular to the surface. Benefiting from this effect, a GaSe microbelt-based photodetector attained a high responsivity of ∼3866 A W−1 and a photoconductive gain of up to ∼1.06 × 104. This study sheds light on the controlled synthesis of microstructures and provides a device design concept for high-performance micro/nano optoelectronics.

OBJECTIVEGamma Knife surgery (GKS) obliterates 65%–87% of cavernous sinus dural arteriovenous fistulas (CSDAVFs). However, the hemodynamic effect on GKS outcomes is relatively unknown. The authors thus used the classification scheme developed by Suh et al. to explore this effect.METHODSThe authors retrospectively (1993–2016) included 123 patients with CSDAVFs who received GKS alone at the institute and classified them as proliferative type (PT; n = 23), restrictive type (RT; n = 61), or late restrictive type (LRT; n = 39) after analyzing their pre-GKS angiography images. Treatment parameters, the presence of numerous arterial feeders, and venous drainage numbers were compared across the CSDAVF types. Patients’ follow-up MR images were evaluated for the presence of complete obliteration. A Kaplan-Meier analysis was conducted to determine the correlation between CSDAVF types and outcomes.RESULTSThe 36-month probability of complete obliteration was 74.3% for all patients, with no significant differences across types (p = 0.56). PT had the largest radiation volume (6.5 cm3, p < 0.001), the most isocenters (5, p = 0.015) and venous drainage routes (3, p < 0.001), and the lowest peripheral dose (16.6 Gy, p = 0.011) and isodose level coverage (64.3%, p = 0.006). CSDAVFs presenting with ocular patterns were less likely to be completely obliterated (hazard ratio 0.531, p = 0.009). After adjustment for age, CSDAVFs with more venous drainage routes were less likely to be completely obliterated (hazard ratio 0.784, p = 0.039).CONCLUSIONSGKS is an equally effective treatment option for all 3 CSDAVF types. Furthermore, the number of venous drainage routes may help in predicting treatment outcomes and making therapeutic decisions.

In this work, we present the assembly of a γ-In2Se3/GaAs heterostructure-based photodetector linear array composed of 1 × 10 device units. The layered γ-In2Se3 films with a well-defined pattern are deposited directly onto a planar GaAs substrate via radio-frequency (RF) magnetron sputtering deposition assisted by a pre-photolithography process. The as-fabricated heterojunction exhibits an apparent photovoltaic effect, which endows the device with a function to operate as a self-driven photodetector. The critical photoresponse performance parameters in terms of the Ilight/Idark ratio, responsivity (R), specific detectivity (D*) and response speed can reach 1.29 × 104, 0.25 A W−1, 7.34 × 1012 Jones and 23.6/146.7 μs (rise/fall times), respectively, upon 660 nm light irradiation at 0 V. What is more, further device evaluation reveals that the photodetector array shows good uniformity with a minor unit-to-unit variation. The above merits endow the photodetector array with the ability to monitor a moving optical signal and to record an “E” image produced by visible illumination. It is believed that the present photodetector array is very promising for some optoelectronic purposes such as real-time light trajectory tracking and visible light image sensing applications.

Most cavernous sinus dural arteriovenous fistulas (CSDAVF) are unilateral; however, simultaneous bilateral CSDAVFs occasionally may be found. This article reports on 141 patients and compares the angioarchitecture and outcomes of embolization of bilateral CSDAVFs with those of unilateral CSDAVFs, with reference to limited demographics (sex and age) of the patients. From January 2010 to February 2018 a total of 141 consecutive patients with CSDAVFs were referred for transvenous embolization. Bilateral CSDAVFs were found in 20 patients (14.2%, with a mean age of 62.2 years). The angioarchitecture of the 141 patients with CSDAVFs were evaluated by conventional cerebral angiography. We compared the angioarchitecture and treatment outcomes of 20 bilateral and 121 unilateral CSDAVFs, and in relation to the patients’ sex and age. Female patients significantly dominated the bilateral CSDAVFs (90%, p = 0.043). Bilateral eye symptoms were significantly more common in bilateral CSDAVFs (p = 0.011), with dominant orbital and cavernous symptoms, and showed statistical significance (p = 0.049 and 0.011, respectively). Occlusion of one CSDAVF may significantly decrease the fistula flow of the other untreated side (n = 13, 65%), leading to less coil utilization for embolization in bilateral CSDAVFs (p

Background Gamma Knife radiosurgery (GKRS) obliterates 65% to 82% of brain arteriovenous malformations (BAVMs). Objective To explore the impact of hemodynamics on GKRS outcomes. Methods We retrospectively (2011-2017) included 98 patients with BAVMs who had received GKRS alone. Two evaluators, blinded to the outcomes, analyzed the pre-GKRS angiography and magnetic resonance images to obtain the morphological characteristics and quantitative digital subtraction angiography (QDSA) parameters. The venous stasis index was defined as the inflow gradient divided by the absolute value of the outflow gradient. Patients' follow-up magnetic resonance or digital subtraction angiography images were evaluated for the presence of complete obliteration (CO). Cox regression and Kaplan-Meier analyses were conducted to determine the correlations between the parameters and outcomes. Results Among the 98 patients, 63 (63.4%) achieved CO after GKRS at a median latency period of 31 mo. In multivariable analyses with adjustments for age and sex, increased BAVM volume (hazard ratio (HR) 0.949, P = .022) was an independent characteristic predictor, and venous stenosis (HR 2.595, P = .009), venous rerouting (HR 0.375, P = .022), and larger stasis index (HR 1.227, P = .025) were independent angiographic predictors of CO. BAVMs with a stasis index of >1.71 had a higher 36-mo probability of CO than those with a stasis index of ≤1.71 (61.1% vs 26.7%, P Conclusion BAVMs with a larger stasis index, indicating more stagnant venous outflow, may predict obliteration after GKRS. QDSA analysis may help in predicting BAVM treatment outcomes and making therapeutic decisions.

Solar-blind deep ultraviolet photodetectors (DUVPDs) based on conventional inorganic ultrawide bandgap semiconductors (UWBS) have shown promising application in various civil and military fields and yet they can hardly be used in wearable optoelectronic devices and systems for lack of mechanical flexibility. In this study, we report a non-UWBS solar-blind DUVPD by designing ultrathin polymer nanofibrils with a virtual ultrawide bandgap, which was obtained by grafting P3HT with PHA via a polymerization process. Optoelectronic analysis reveals that the P3HT-b-PHA nanofibrils are sensitive to DUV light with a wavelength of 254 nm but are virtually blind to both 365 nm and other visible light illuminations. The responsivity is 120 A/W with an external quantum efficiency of up to 49700%, implying a large photoconductive gain in the photoresponse process. The observed solar-blind DUV photoresponse is associated with the resonant mode due to the leakage mode of the ultrathin polymer nanofibrils. Moreover, a flexible image sensor composed of 10 × 10 pixels can also be fabricated to illustrate their capability for image sensing application. These results signify that the present ultrathin P3HT-b-PHA nanofibrils are promising building blocks for assembly of low-cost, flexible, and high-performance solar-blind DUVPDs.

In this work, a sensitive deep ultraviolet (DUV) light photodetector based on inorganic and lead-free Cs3Cu2I5 crystalline film derived by a solution method was reported. Optoelectronic characterization revealed that the perovskite device exhibited nearly no sensitivity to visible illumination with wavelength of 405 nm but exhibited pronounced sensitivity to both DUV and UV light illumination with response speeds of 26.2/49.9 ms for rise/fall time. The Ilight/Idark ratio could reach 127. What is more, the responsivity and specific detectivity were calculated to be 64.9 mA W-1 and 6.9 × 1011 Jones, respectively. In addition, the device could keep its photoresponsivity after storage in air environment for a month. It is also found that the capability of Cs3Cu2I5 crystalline film device can readily record still DUV image with acceptable resolution. The above results confirm that the DUV photodetector may hold great potential for future DUV optoelectronic device and systems.

To compare the therapeutic efficacy between warm needling moxibustion and electroacupuncture (EA) in the treatment of simple obesity due to yang deficiency of the spleen and kidney. Seventy patients with simple obesity due to yang deficiency of the spleen and kidney were randomly divided into a warm needling moxibustion group and an EA group, with 35 subjects in each group. Same major acupoints were selected for the two groups, including Shuifen (CV 9), Guanyuan (CV 4), Daheng (SP 15), Shuidao (ST 28), Shousanli (LI 10), Zusanli (ST 36), Sanyinjiao (SP 6) and Taixi (KI 3). The warm needling moxibustion group received warm needling moxibustion, while the EA group received EA treatment. The interventions were performed once every other day, with 15 treatments as one course. The therapeutic efficacy, body weight and body mass index (BMI) were then observed and compared. The total effective rate in the warm needling moxibustion group was 85.7% versus 77.1% in the EA group, and the between-group difference was statistically significant (P

BACKGROUND Quantitative digital subtraction angiography (DSA) facilitates in-room assessment of flow changes in various cerebrovascular diseases and improves patient safety. The purpose of this study was to compare the diagnostic accuracy of quantitative fluoroscopic angiography (FA) and DSA. METHODS Twenty-two patients with >70% carotid stenosis according to NASCET criteria were prospectively included in the study. All patients received DSA and FA (ArtisZee, Siemens Healthcare, Forchheim, Germany) before and after carotid stenting in the same angiosuite. The regions of interest (ROIs) included the extracranial internal carotid artery (eICA), first segment of the middle cerebral artery (MCA1), and sigmoid sinus in the anterior-posterior view; cavernous portion of the ICA (cICA), parietal vein, and jugular vein in the lateral views. The time-to-peak (TTP) for all ROIs and cerebral circulation time (CCT) were measured from FA and DSA scans. TTP, CCT, and radiation doses from DSA were compared with those from FA. RESULTS The mean age of the patients were 69 ± 9.5 years old. The average stenosis was 89.7% ± 7.8% before stenting and 31% ± 3.6% after stenting. No patient suffered from periprocedural stroke. The intermethod correlation for TTP for all ROIs except the eICA and cICA ranged from 0.46 to 0.65 before stenting and 0.57 to 0.73 after stenting, and that for CCT was 0.65 before stenting and 0.57 after stenting. The radiation doses were significantly lower for FA than for DSA regardless of views or periprocedural timing (p < 0.001). CONCLUSION Stenosis facilitated the creation of a bolus by manual injection and therefore increased the accuracy of cerebral flow quantification in FA. Cerebral hemodynamic assessment by FA is quicker and associated with less radiation.

OBJECTIVE The aim of the study was to evaluate cerebral hemorrhage (CH) and contrast media leakage (CML or commonly synonymous with "contrast staining") differentiation on flat-panel volume computed tomography (FPVCT) after intra-arterial mechanical thrombectomy. METHODS We evaluated patients with hyperattenuation on FPVCT after intra-arterial mechanical thrombectomy between 2018 and 2021 by multiple parameters on CT angiography, FPVCT, CT, and/or magnetic resonance imaging. RESULTS The CH (n = 43) versus CML (n = 24) groups revealed: (1) regional anatomical characteristics (preserved and distorted): 7 of 43 (9.6%) and 36 of 43 (83.7%) versus 22 of 24 (91.7%) and 2 of 24 (8.3%, P < 0.001); (2) thrombus in proximal two-thirds versus distal one-thirds M1 segment of middle cerebral artery (preserved and distorted): 17 of 21 (81.0%) and 4 of 21 (19.0%) versus 5 of 11 (45.5%) and 6 of 11 (54.5%, P = 0.040); and (3) average density ratio: 1.83 ± 0.65 versus 1.35 ± 0.13 (P = 0.004). CONCLUSIONS Contrast media leakage can be differentiated from CH by preserved regional anatomical characteristics and relatively low average density ratio on FPVCT. Patients with CML who have embolism in proximal two thirds of M1 segment are more likely to develop hyperattenuation with preserved regional anatomy.

BACKGROUND Carotid blowout syndrome (CBS) is a catastrophic complication after aggressive head and neck cancer treatment. Endovascular embolization is an effective modality to manage CBS. However, some CBS may have recurrent CBS (rCBS) after endovascular management. This study aims to report the potential rCBS risk and endovascular management strategy. METHODS Of the 225 patients with CBS referred for embolization in 13 years, 31 men and one woman (mean age, 55 years) with 35 rCBS with pseudoaneurysms formation were identified after endovascular management. Moreover, the rCBS preembolization angioarchitecture, rCBS cause, rCBS time interval, embolic materials selection, and final embolization clinical/angiographic outcomes were retrospectively analyzed. RESULTS rCBS with pseudoaneurysm due to disease progression (DP) occurred in 17 patients, while 15 patients had insufficient embolization (IE) with 18 rCBS. The mean rCBS timing interval was 76 days with 129 and 12 days due to DP or IE. The most common rCBS locations were the carotid bulb and the main trunk of the external carotid artery (n = 20, 57%), followed by internal carotid artery (n = 8, 23%), distal branch of the external carotid artery (n = 4, 11%), and common carotid artery (n = 3, 9%). Endovascular management was technically successful in all patients by reconstruction (n = 7, 20%) or destruction (n = 28, 80%) techniques. Three patients (9%) had procedure-related complications. No rCBS was observed in all affected arteries after the last embolization in a mean 11-month clinical follow-up. CONCLUSION rCBS may result from DP or IE. The common location of IE-related rCBS usually occurred in the carotid branches. It occurred within two weeks of CBS largely because of the underestimation of the extension of the affected carotid artery. In addition, DP is natural in head and neck cancer after aggressive treatment. Thus, endovascular management remained an effective method to manage rCBS.

This work reports the design of a wavelength sensor composed of two identical perovskite (FA0.85 Cs0.15 PbI3 ) photodetectors (PDs) that are capable of discriminating incident wavelength in a quantitative way. Due to strong wavelength-dependent absorption coefficient, the penetration depth of the photons in the FA0.85 Cs0.15 PbI3 nanofilms increases with the increasing wavelength, leading to a gradual decrease of photo-generated current for PD1, but an increase of photocurrent in PD2, according to the theoretical simulation of Technology Computer Aided Design. This special evolution of photo-generated current as a function of wavelength facilitates the quantitative determination of the wavelength since the current ratio of both PDs monotonously decreases with the increase of wavelength from 265 to 810 nm. The average absolute error and the average relative error are estimated to be 7.6 nm and 1.68%, respectively, which are much better than other semiconductors materials-based wavelength sensors previously reported. It is believed that the present perovskite film-based wavelength sensor will have potential application in the future color/spectrum optoelectronic devices.

Background/purpose The therapeutic efficacy of percutaneous transluminal angioplasty and stenting (PTAS) of post-irradiated stenosis of subclavian artery (PISSA) was not well clarified. This retrospective study was designed to evaluate the technical safety and outcome of the patients of severe symptomatic PISSA accepted PTAS. Methods Between 2000 and 2019, 16 cases with 17 lesions of symptomatic and medically refractory PISSA accepted PTAS were included. We evaluated their technical success, peri-procedural complications and diffusion-weight imaging (DWI) of brain magnetic resonance imaging (MRI), results of symptom relief, and long-term stent patency. Results The stenosis of the 17 stenotic lesions were 81.2 ± 11.1%. The most common symptom of the 16 patients was dizziness (14/16, 87.5%). All successfully accepted PTAS without neurological complication and had symptom relief after PTAS (17/17, 100%). Of the 12 patients accepted pre-procedural and early post-procedural MRI follow-up, 2 patients had an asymptomatic tiny acute embolic infarct in the territory of vertebrobasilar system. In a 51.9 ± 54.9 months follow-up, all patients had no severe restenosis and no recurrent vertebrobasilar ischemic symptoms. Conclusion For patients with PISSA and medically refractory ischemic symptoms, PTAS can be an effective alternative management.

A γ-In2Se3/Si heterostructure phototransistor with a broadened photoresponse has been developed, presenting a responsivity, specific detectivity and response speed of 10.24 A W−1, 8.63 × 1012 Jones and 0.76/0.85 ms (rise time/fall time) at 450 nm, respectively. The high responsivity could be attributed to the depressed dark current of the γ-In2Se3 nanofilm and the high gain arising from the gating effect of the phototransistor. Further analysis reveals that the relatively high responsivity and fast response speed facilitate the application of the device in real-time and accurate health monitoring, such as heart rate detection.

In this work, we have developed a wavelength sensor that is capable of distinguishing illumination with wavelengths ranging from ultraviolet (UV) to near infrared (NIR). The as-proposed wavelength sensor is geometrically composed of two parallelly stacking graphene (Gr)/thin Si/Gr heterojunction devices, which are identical in device structures, but can display completely different optical properties in terms of distribution of photo-absorption and photo-generation rates under various light illuminations, according to theoretical simulation. Such a discrepancy in optical properties due to a wavelength dependent absorption coefficient and the relatively thin Si wafer gives rise to completely different photocurrent evolution for varied wavelengths of illumination. The relationship between the photocurrent ratio of devices, the wavelength and intensity of incident light can be numerically described by an equation, through which the wavelength in the range from 265 to 1050 nm can be accurately determined. Notably, the average root-mean-square error of this wavelength sensor is about 2.30 nm, with a relative error as low as ±1.5%, which is much better than other wavelength detectors previously reported. These results suggest that the present wavelength sensor may find potential application for future optoelectronic systems.

BACKGROUND Endovascular management is used to treat Takayasu arteritis (TA) involving the supra-aortic branches. However, the long-term outcome of this treatment remains unclear. Here, technical safety, outcomes, and restenosis management of supra-aortic arteries in TA patients receiving endovascular treatment were evaluated. METHODS TA patients with symptomatic supra-aortic stenosis who underwent percutaneous angioplasty and stenting between 2008 and 2018 at our institute were enrolled in this study. Pre- and post-procedural magnetic resonance imaging (MRI) evaluations, including high-resolution vessel wall imaging (HR-VWI), were performed. Technical efficacy, peri-procedural complications, early post-procedural MRI results, and stent patency were examined. RESULTS All six patients successfully received stent placement or percutaneous transluminal angioplasty in a total of 22 treated arteries without neurologic complications. During follow-up (mean, 56.3 ± 41.1 months), no recurrent stroke occurred, yet significant restenosis developed in 12 of 22 (54.5%) of the treated arteries. Three of the patients underwent HR-VWI before surgery. Concentric wall thickening and enhancement of the left common carotid artery was detected in one patient, indicating acute inflammation. Angioplasty with drug-eluting balloon (DEB) successfully treated a case of refractory restenosis. Among 10 early post-procedure MRI performed, only two asymptomatic new lesions were detected with diffusion-weighted imaging. CONCLUSION Endovascular treatment of supra-aortic arteries of TA patients was safe and effective, yet was associated with a high restenosis rate. Thus, close follow-up is needed. HR-VWI is helpful for pre-procedural selection of patients for percutaneous angioplasty and stenting and drug-eluting balloon angioplasty appears to be a promising treatment for refractory in-stent restenosis.

In a spoken multiple-choice question answering (SMCQA) task, given a passage, a question, and multiple choices all in the form of speech, the machine needs to pick the correct choice to answer the question. While the audio could contain useful cues for SMCQA, usually only the auto-transcribed text is utilized in system development. Thanks to the large-scaled pre-trained language representation models, such as the bidirectional encoder representations from transformers (BERT), systems with only auto-transcribed text can still achieve a certain level of performance. However, previous studies have evidenced that acoustic-level statistics can offset text inaccuracies caused by the automatic speech recognition systems or representation inadequacy lurking in word embedding generators, thereby making the SMCQA system robust. Along the line of research, this study concentrates on designing a BERT-based SMCQA framework, which not only inherits the advantages of contextualized language representations learned by BERT, but integrates the complementary acoustic-level information distilled from audio with the text-level information. Consequently, an audio-enriched BERT-based SMCQA framework is proposed. A series of experiments demonstrates remarkable improvements in accuracy over selected baselines and SOTA systems on a published Chinese SMCQA dataset.

BACKGROUND Clinical and radiological outcomes of endovascular thrombectomy (EVT) are related to etiologies of large vessel occlusion (LVO) in acute stroke. However, preprocedural computed tomography angiography (CTA) or CT perfusion imaging can hardly distinguish embolic occlusion from atherosclerotic occlusion. We hypothesized that quantitative multiphase CTA (mCTA) of LVO may predict occlusion types and thrombectomy outcome. METHODS We retrospectively evaluated the consecutive stroke patients who had undergone mCTA and EVT

BACKGROUND Endovascular thrombectomy (EVT) has become the standard treatment for acute ischemic stroke with large vessel occlusion. Atrial fibrillation (AF) is one of the major causes. However, the impact of AF on the treatment has not yet been clearly discussed. This study is to evaluate the influence of AF on the outcomes of EVT in patients with acute ischemic stroke. METHODS Data from our Stroke Registry Database from April 2015 to July 2018 were reviewed. Technical efficacy, functional, and safety outcomes were reported and compared between patients with and without AF. A multivariate logistic regression model was performed to identify the predictors of the good functional outcome. RESULTS We reviewed 83 eligible patients receiving EVT. Patients (51.8%) were eventually found to have AF. The substantial reperfusion rate (modified thrombolysis in cerebral infarction 2b-3) was 72.1% and 55.0% in patients with and without AF, respectively, inclusive of a learning curve (p = 0.12). The good functional outcome (90-day modified Rankin scale: 0 to 2) rate was 55.8% and 17.5% in patients with and without AF, respectively (p < 0.01). A multivariable logistic regression analysis showed that age

Remote sensing has been recognized as a cost-effective way to detect the spatial and temporal variability of crop growth and productivity. In this study, multispectral RapidEye images were used to delineate homogeneous zones of soil and crop development in two fields in Ontario, Canada, one planted with canola (Brassica napus L.) and the other with spring wheat (Triticum aestivum L.). The two fields received different levels of nitrogen (N) treatments during the pre-planting land preparation phase. Soil textures, mineral nitrogen content and crop yield were used to interpret the results of zone delineation. The analysis of variance (ANOVA) tests revealed that the high-resolution RapidEye data, particularly the imagery acquired at peak crop growth stages (i.e. when leaf area index (LAI) is high), provided valuable information for delineating within-field variability of crop growth and yield. Further analysis showed that for both crops, the spatial patterns of crop growth condition varied throughout the growth cycle, revealing different impacts of soil properties and N fertilization on the crops. In particular, during peak growth stage, the within-field variability was most strongly affected by the pre-planting N application and had the strongest correlation with crop yield. These results suggest that high-resolution satellite data (e.g., RapidEye) could assist in making decisions on optimal N fertilization for enhanced crop productivity.

We present the first report of a new suspension method for obtaining cubic MAPbBr3 single crystal with a concave surface. The cubic MAPbBr3 crystal with microconcavity possesses good crystallinity and carrier lifetime. Excellent photoelectric performance was provided by the concavity-based MAPbBr3 photodetectors because of the good light trapping and shortened carrier pathway. As a result, the concavity-based photodetector exhibits superior responsivity of 62.9 and 5.43 A W–1 and EQE of 1.50 × 104% and 1.30 × 103% under low-power and high-power 520 nm irradiation of 3.67 μW cm–2 and 35.4 mW cm–2 at 3 V, respectively, which are more than 500% higher than those of the plane-based photodetector. In particular, the concavity-based photodetector has an ultrahigh detectivity of 6.5 × 1012 Jones at ultralow power of 3.67 μW cm–2, which is 6.5 times higher than that of the planar device.

Background Certain types of pediatric intracranial germ cell tumors (PIGCTs) are prone to intratumoral hemorrhaging (TH) and associated with poor survival outcome. However, the impact of TH on the functional prognosis of patients with PIGCTs has not been well studied. This study aimed to evaluate the clinical and MR findings in PIGCT patients with TH to identify the factors related to patient survival and functional outcome. Methods This study included 17 patients diagnosed with PIGCT and TH between 2002 and 2016 and evaluated TH-associated clinical and MR findings. The modified Rankin scale (mRS) was used to evaluate functional outcome, which was poor when mRS ≧ 3. The volumes of hematomas and tumors were manually tracked within each brain magnetic resonance imaging slice. Results Among the 17 patients, 6 (35.3%) died and 9 (52.9%) had poor functional outcome. Regarding the functional outcome, the mean hematoma volume to tumor volume ratio (HTVR) was 8.5 ± 3.9% in the favorable outcome group and 42.3 ± 27.8% in the poor outcome group (p = 0.001). For the survival outcome, the mean HTVR was 15.7 ± 16.1% in the living group and 46.0 ± 31.5% in the deceased group (p = 0.016). The cutoff point of the receiver operating characteristics curve for HTVR to predict death and poor functional outcome was 19.27% and 16.8%, respectively. Conclusion Our study demonstrated that patients with larger HTVR had significantly worse functional and survival outcomes than those with smaller HTVR. We suggest that early and aggressive treatment for PIGCTs in patients with large HTVR can improve their long-term prognosis.

Light detection in the near-infrared (NIR) region is of particular importance due to its wide application for both military and civil purposes. In this study, we fabricated high-performance NIR photodetectors by simply transferring a multilayered PtSe2 film onto a Ge wafer to form vertical hybrid heterojunctions. These heterojunctions exhibit an apparent photovoltaic effect under NIR illumination, offering our devices the opportunity to operate without an external power supply. Based on further optoelectronic analysis, it was found that the devices were highly sensitive to the 1300, 1550, 1650 and even 2200 nm NIR illumination with good reproducibility and long-term air stability. Under the 1550 nm irradiation, the NIR photodetectors attained the high responsivity and specific detectivity of 602 mA W−1 and 6.3 × 1011 Jones, respectively, along with fast response speed of 7.4/16.7 μs at zero bias. Due to the excellent photoresponse performance and the simple device geometry, the present self-driven NIR photodetectors are very promising for application in future optoelectronic devices and systems.

In this study, we report on the synthesis of layered γ-In2Se3 for broadband photodetector and near infrared light image sensing applications. The layered γ-In2Se3 nanofilm with a thickness of around 74 nm was deposited onto a n-Si wafer through radio frequency magnetron sputtering. It is found that the as-assembled γ-In2Se3/n-Si shows an obvious photovoltaic behavior and can work properly as a self-powered broadband photodetector over a wide range of wavelengths (200–2200 nm). Such a unique spectral response beyond the absorption limit of both intrinsic γ-In2Se3 and n-Si can be ascribed to the existence of defect energy levels between the valence band and the conduction band, as a result of Se substitution of In atoms according to theoretical simulation based on first-principles calculations. Specifically, the γ-In2Se3/n-Si photodetector has a responsivity of 0.57 A W−1, a specific detectivity of 2.6 × 1012 Jones and a fast response speed (35/115 μs for τr/τf) under 808 nm light illumination, respectively, which are slightly better or comparable to other devices with similar geometries. Lastly, it was revealed that the γ-In2Se3/n-Si heterojunction photodetector can function as an effective near infrared (NIR) light image sensor with a decent spatial resolution, which suggests the great potential of the current device in future NIR optoelectronic systems.