High power self-Q-switched Tm:YAP laser.

To the best of our knowledge, the output performance of a self-Q-switched Tm:YAP laser has been controlled by adjusting the cavity length for the first time. By using a concise concave-flat cavity, a pulsed laser emitting at 1993 nm is produced without any additional modulation device. Under a stable self-Q-switched mode, the maximum average output power of 9.76 W is achieved from the laser when the incident pump power is 28.78 W, corresponding to a slope efficiency of 36.9% and an optical-to-optical conversion efficacy of 33.9%. Also, the narrowest pulse width of 485 ns at 48.97 kHz is obtained from the laser with a single pulse energy of 199.3 µJ. As far as we know, this laser has the highest average power and narrowest pulse width compared to other self-Q-switched Tm:YAP lasers.

Waveguide-Integrated Light-Emitting Metal-Insulator-Graphene Tunnel Junctions.

Ultrafast interfacing of electrical and optical signals at the nanoscale is highly desired for on-chip applications including optical interconnects and data processing devices. Here, we report electrically driven nanoscale optical sources based on metal-insulator-graphene tunnel junctions (MIG-TJs), featuring waveguided output with broadband spectral characteristics. Electrically driven inelastic tunneling in a MIG-TJ, realized by integrating a silver nanowire with graphene, provides broadband excitation of plasmonic modes in the junction with propagation lengths of several micrometers (∼10 times larger than that for metal-insulator-metal junctions), which therefore propagate toward the junction edge with low loss and couple to the nanowire waveguide with an efficiency of ∼70% (∼1000 times higher than that for metal-insulator-metal junctions). Alternatively, lateral coupling of the MIG-TJ to a semiconductor nanowire provides a platform for efficient outcoupling of electrically driven plasmonic signals to low-loss photonic waveguides, showing potential for applications at various integration levels.

Highly sensitive fiber-optic temperature sensor with compact hybrid interferometers enhanced by the harmonic Vernier effect.

A compact fiber-optic temperature sensor with hybrid interferometers enhanced by the harmonic Vernier effect was proposed, which realized 36.9 times sensitization of the sensing Fabry-Perot interferometer (FPI). The hybrid interferometers configuration of the sensor consists of a FPI and a Michelson interferometer. The proposed sensor is fabricated by splicing the hole-assisted suspended-core fiber (HASCF) to the multi-mode fiber fused with the single-mode fiber, and filling polydimethylsiloxane (PDMS) into the air hole of HASCF. The high thermal expansion coefficient of PDMS improves the temperature sensitivity of the FPI. The harmonic Vernier effect eliminates the limitation of the free spectral range on the magnification factor by detecting the intersection response of internal envelopes, and realizes the secondary sensitization of the traditional Vernier effect. Combing the characteristics of HASCF, PDMS, and first-order harmonic Vernier effect, the sensor exhibits a high detection sensitivity of -19.22 nm/°C. The proposed sensor provides not only a design scheme for compact fiber-optic sensors, but also a new strategy to enhance the optical Vernier effect.

Impact of delayed veno-venous extracorporeal membrane oxygenation weaning on postoperative rehabilitation of lung transplantation: a single-center comparative study.

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is a reliable and effective extracorporeal life support during lung transplantation (LTx). However, the clinical benefit of delayed VV-ECMO weaning remains unclear. The current study aims to investigate whether delayed weaning of VV-ECMO is more beneficial to the rehabilitation for lung transplant patients. Patients who underwent LTx with VV-ECMO between January 2017 and January 2019 were included. Enrollment of patients was suitable for weaning off ECMO immediately after surgery. Randomization was performed in the operating room. Postoperative outcomes were compared between the two groups. Besides, univariate and multivariable logistic regressions were performed to estimate risk of postoperative complications. Compared to VV-ECMO weaning immediately after LTx, delayed weaning was associated with shorter hospital length of stay (days, 31 vs. 46; P < 0.05), lower incidence of noninvasive ventilation (4.3% vs. 24.4%; P < 0.05), primary graft dysfunction (PGD) (6.4% vs. 29.3%; P < 0.05), atrial fibrillation (AF) (4.3% vs. 22%, P < 0.05), and respiratory failure (4.3% vs. 19.5%; P < 0.05). Multivariable logistic regressions revealed that VV-ECMO weaning after LTx was independently correlated with increased risk of developing PGD [odds ratio (OR), 5.97, 95% CI 1.16-30.74], AF (OR, 6.87, 95% CI 1.66-28.47) and respiratory failure (OR, 6.02, 95% CI 1.12-32.49) by comparison of delayed VV-ECMO weaning. Patients with delayed VV-ECMO weaning are associated with lower complications and short hospital length of stay, while it relates to longer mechanical ventilation. These findings suggest that delayed VV-ECMO after LTx can facilitate rehabilitation.

Neoadjuvant camrelizumab plus chemotherapy in locally advanced oesophageal squamous cell carcinoma: a retrospective cohort study.

BACKGROUND: Neoadjuvant therapy is recommended to improve the prognosis of oesophageal squamous cell carcinoma (ESCC). As a PD-1 inhibitor developed in China, camrelizumab is more accessible and available for Chinese ESCC patients. Camrelizumab plus neoadjuvant chemotherapy has shown promising efficacy with acceptable toxicity for resectable ESCC in the NIC-ESCC2019 trial. However, this was a single-arm trial, so we conducted a retrospective cohort study to compare neoadjuvant camrelizumab plus chemotherapy with neoadjuvant chemotherapy alone in terms of the safety and efficacy in patients with locally advanced ESCC. METHODS: Between January 2017 and December 2021, patients with stage II-IVa ESCC who received neoadjuvant therapy at the First Affiliated Hospital of Chongqing Medical University and underwent radical oesophagectomy were enrolled in our study. These included 19 patients who received neoadjuvant chemotherapy plus camrelizumab (group 1) and 40 patients who only received neoadjuvant chemotherapy (group 2). RESULTS: The baseline characteristics of the patients were comparable between the two groups. The pathological complete response (pCR) rate in group 1 was significantly higher than that in group 2 (26.3% vs. 2.5%, P = 0.018). All patients in group 1 achieved complete resection (R0), compared with 39 (97.5%) patients in group 2. Adverse events occurred in 16 (84%) patients in group 1 versus 35 (87.5%) patients in group 2. No grade ≥ 4 adverse events occurred in either group. No significant difference was found in surgical outcomes or postoperative complications. The 90-day mortality rate was comparable between the two groups (1 patient died in group 1 versus 2 patients in group 2). CONCLUSIONS: Neoadjuvant camrelizumab plus chemotherapy followed by surgery was associated with a promising pCR rate and a manageable safety profile for patients with locally advanced ESCC.

Atomically Smooth Single-Crystalline Platform for Low-Loss Plasmonic Nanocavities.

Nanoparticle-on-mirror plasmonic nanocavities, capable of extreme optical confinement and enhancement, have triggered state-of-the-art progress in nanophotonics and development of applications in enhanced spectroscopies. However, the optical quality factor and thus performance of these nanoconstructs are undermined by the granular polycrystalline metal films (especially when they are optically thin) used as a mirror. Here, we report an atomically smooth single-crystalline platform for low-loss nanocavities using chemically synthesized gold microflakes as a mirror. Nanocavities constructed using gold nanorods on such microflakes exhibit a rich structure of plasmonic modes, which are highly sensitive to the thickness of optically thin (down to ∼15 nm) microflakes. The microflakes endow nanocavities with significantly improved quality factor (∼2 times) and scattering intensity (∼3 times) compared with their counterparts based on deposited films. The developed low-loss nanocavities further allow for the integration with a mature platform of fiber optics, opening opportunities for realizing nanocavity-based miniaturized photonic devices for practical applications.

New insight into scale inhibition during tea brewing: Ca2+/Mg2+ complexing and alkalinity consumption.

Scale not only affects the taste and color of water, but also increases the risks of osteoporosis and cardiovascular diseases associated with drinking it. As a popular beverage, tea is rich many substances that have considerable potential for scale inhibition, including protein, tea polyphenols and organic acids. In this study, the effect of tea brewing on scale formation was explored. It was found that the proteins, catechins and organic acids in tea leaves could be released when the green tea was brewed in water with sufficient hardness and alkalinity. The tea-released protein was able to provide carboxyl groups to chelate with calcium ions (Ca2+), preventing the Ca2+ from reacting with the carbonate ions (CO32-). The B rings of catechins were another important structure in the complexation of Ca2+ and magnesium ions (Mg2+). The carboxyl and hydroxyl groups on the organic acids was able to form five-membered chelating rings with Ca2+ and Mg2+, resulting in a significant decrease in Ca2+ from 100.0 to 60.0 mg/L. Additionally, the hydrogen ions (H+) provided by the organic acids consumed and decreased the alkalinity of the water from 250.0 to 131.4 mg/L, leading to a remarkable reduction in pH from 8.93 to 7.73. It further prevented the bicarbonate (HCO3-) from producing CO32- when the water was heated. The reaction of the tea constituents with the hardness and alkalinity inhibited the formation of scale, leading to a significant decrease in turbidity from 10.6 to 1.4 NTU. Overall, this study provides information to help build towards an understanding of the scale inhibition properties of tea and the prospects of tea for anti-scaling in industrial applications.

Passively Q-switched Tm:YAP laser with a tantalum aluminum carbide saturable absorber.

Tantalum aluminum carbide (Ta4AlC3) phase ceramic (MAX) material has attracted much attention because of its high conductivity, high strength, corrosion resistance, and good optical properties. However, there are too few reports on lasers with Ta4AlC3-based saturable absorbers (SAs). We prepared and characterized a Ta4AlC3-based SA whose nonlinear absorption performances were achieved at a 2 µm waveband range and which was used in a passively Q-switched (PQS) Tm:YAP laser. In the PQS mode, a maximum average output power of 0.78 W was achieved with the central output wavelength of 1991.86 nm from a PQS Tm:YAP laser, corresponding to a pulse duration of 926 ns at 143.8 kHz.

Individualized model for predicting COVID-19 deterioration in patients with cancer: A multicenter retrospective study.

The 2019 novel coronavirus has spread rapidly around the world. Cancer patients seem to be more susceptible to infection and disease deterioration, but the factors affecting the deterioration remain unclear. We aimed to develop an individualized model for prediction of coronavirus disease (COVID-19) deterioration in cancer patients. The clinical data of 276 cancer patients diagnosed with COVID-19 in 33 designated hospitals of Hubei, China from December 21, 2019 to March 18, 2020, were collected and randomly divided into a training and a validation cohort by a ratio of 2:1. Cox stepwise regression analysis was carried out to select prognostic factors. The prediction model was developed in the training cohort. The predictive accuracy of the model was quantified by C-index and time-dependent area under the receiver operating characteristic curve (t-AUC). Internal validation was assessed by the validation cohort. Risk stratification based on the model was carried out. Decision curve analysis (DCA) were used to evaluate the clinical usefulness of the model. We found age, cancer type, computed tomography baseline image features (ground glass opacity and consolidation), laboratory findings (lymphocyte count, serum levels of C-reactive protein, aspartate aminotransferase, direct bilirubin, urea, and d-dimer) were significantly associated with symptomatic deterioration. The C-index of the model was 0.755 in the training cohort and 0.779 in the validation cohort. The t-AUC values were above 0.7 within 8 weeks both in the training and validation cohorts. Patients were divided into two risk groups based on the nomogram: low-risk (total points ≤ 9.98) and high-risk (total points > 9.98) group. The Kaplan-Meier deterioration-free survival of COVID-19 curves presented significant discrimination between the two risk groups in both training and validation cohorts. The model indicated good clinical applicability by DCA curves. This study presents an individualized nomogram model to individually predict the possibility of symptomatic deterioration of COVID-19 in patients with cancer.

Association between recent oncologic treatment and mortality among patients with carcinoma who are hospitalized with COVID-19: A multicenter study.

BACKGROUND: To the authors' knowledge, little is known regarding the association between recent oncologic treatment and mortality in patients with cancer who are infected with coronavirus disease 2019 (COVID-19). The objective of the current study was to determine whether recent oncologic treatment is associated with a higher risk of death among patients with carcinoma who are hospitalized with COVID-19. METHODS: Data regarding 248 consecutive patients with carcinoma who were hospitalized with COVID-19 were collected retrospectively from 33 hospitals in Hubei Province, China, from January 1, 2020, to March 25, 2020. The follow-up cutoff date was July 22, 2020. Univariable and multivariable logistic regression analyses were performed to identify variables associated with a higher risk of death. RESULTS: Of the 248 patients enrolled, the median age was 63 years and 128 patients (52%) were male. On admission, 147 patients (59%) did not undergo recent oncologic treatment, whereas 32 patients (13%), 25 patients (10%), 12 patients (5%), and 10 patients (4%), respectively, underwent chemotherapy, surgery, targeted therapy, and radiotherapy. At the time of last follow-up, 51 patients (21%) were critically ill during hospitalization, 40 of whom had died. Compared with patients without receipt of recent oncologic treatment, the mortality rate of patients who recently received oncologic treatment was significantly higher (24.8% vs 10.2%; hazard ratio, 2.010 [95% CI, 1.079-3.747; P = .027]). After controlling for confounders, recent receipt of chemotherapy (odds ratio [OR], 7.495; 95% CI, 1.398-34.187 [P = .015]), surgery (OR, 8.239; 95% CI, 1.637-41.955 [P = .012]), and radiotherapy (OR, 15.213; 95% CI, 2.091-110.691 [P = .007]) were identified as independently associated with a higher risk of death. CONCLUSIONS: The results of the current study demonstrated a possible association between recent receipt of oncologic treatment and a higher risk of death among patients with carcinoma who are hospitalized with COVID-19.

Passively Q-switched Tm:YAP laser with a lead zirconate titanate saturable absorber.

In the paper, we prepare a lead zirconate titanate saturable absorber, which is used to demonstrate a passively Q-switched (PQS) Tm:YAP laser. In the PQS mode, an average output power of 0.81 W and pulse width of 1.69 µs at 175 kHz are obtained at 1991.9 nm with a pump power of 12.76 W, corresponding to an optical-optical conversion efficiency of 6.35%. In addition, the beam quality factors M2 of the PQS Tm:YAP laser in the x and y directions are 1.17 and 1.15, respectively.

A Review of Coating Materials Used to Improve the Performance of Optical Fiber Sensors.

In order to improve the performance of fiber sensors and fully tap the potential of optical fiber sensors, various optical materials have been selectively coated on optical fiber sensors under the background of the rapid development of various optical materials. On the basis of retaining the original characteristics of the optical fiber sensors, the coated sensors are endowed with new characteristics, such as high sensitivity, strong structure, and specific recognition. Many materials with a large thermal optical coefficient and thermal expansion coefficients are applied to optical fibers, and the temperature sensitivities are improved several times after coating. At the same time, fiber sensors have more intelligent sensing capabilities when coated with specific recognition materials. The same/different kinds of materials combined with the same/different fiber structures can produce different measurements, which is interesting. This paper summarizes and compares the fiber sensors treated by different coating materials.

Modulating Charge Density Wave Order in a 1T-TaS2/Black Phosphorus Heterostructure.

Controllability of collective electron states has been a long-sought scientific and technological goal and promises development of new devices. Herein, we investigate the tuning of charge density wave (CDW) in 1T-TaS2 via a two-dimensional (2D) van der Waals heterostructure of 1T-TaS2/BP. Unusual gate-dependent conductance oscillations were observed in 1T-TaS2 nanoflake supported on BP in transport measurements. Scanning tunneling microscopy study shows that the nearly commensurate (NC) CDW phase survived to 4.5 K in this system, which is substantially lower than the NC to commensurate CDW phase transition temperature of 180 K. A Coulomb blockade model was invoked to explain the conductance oscillations, where the domain walls and domains in NC phase serve as series of quantum dot arrays and tunnelling barriers, respectively. Density functional theory calculations show that a range of interfacial interactions, including strain and charge transfer, influences the CDW stabilities. Our work sheds light on tuning CDW orders via 2D heterostructure stacking and provides new insights on the CDW phase transition and sliding mechanism.

Anomalous Quantum Metal in a 2D Crystalline Superconductor with Electronic Phase Nonuniformity.

The details of the superconducting to quantum metal transition (SQMT) at T = 0 are an open problem that invokes great interest in the nature of this exotic and unexpected ground state (Ephron et al., 1996; Mason and Kapitulnik, 1999; Chervenak and Valles, 2000). However, the SQMT was not yet investigated in a crystalline 2D superconductor with coexisting and fluctuating quantum orders. Here, we report the observation of a SQMT in 2D ion-gel-gated 1T-TiSe2 (Li et al., 2016) driven by a magnetic field. A field-induced crossover between Bose quantum metal and vortex quantum creeping with an increasing field is observed. We discuss the interplay between superconducting and CDW fluctuations (discommensurations) and their relation to the anomalous quantum metal (AQM) phase. From our findings, gate-tunable 1T-TiSe2 emerges as a privileged platform to scrutinize, in a controlled way, the details of the SQMT, the role of coexisting fluctuating orders and, ultimately, to obtain a deeper understanding of the fate of superconductivity in strictly two-dimensional crystals near zero temperature.

Efficient Ho:(Sc0.5Y0.5)2SiO5 laser at 2.1 µm in-band pumped by Tm fiber laser.

In this paper, we demonstrate a new 2.1-µm Ho:(Sc0.5Y0.5)2SiO5 (Ho:SYSO) laser at room temperature. The absorption and emission spectra of Ho:SYSO crystal were studied at temperature of 300 K. The strongest absorption peak of 5I7 level of Ho ions in SYSO crystal is located at 1943 nm with cross section of 0.79 × 10-20 cm2. The maximum emission cross section of 1.74 × 10-20 cm2 is located at 2032 nm. A 1940.3-nm narrow-linewidth Tm fiber was used to pump the Ho:SYSO crystal. At absorbed pump power of 20.4 W, the continuous wave Ho:SYSO laser yielded 10.3 W maximum output power at 2097.67 nm and 54.7% slope efficiency respect with absorbed pump power. In addition, we have estimated the beam quality factor (M2) of Ho:SYSO laser to be 1.7 near maximum output level.

Active Q-switching operation of slab Ho:SYSO laser wing-pumped by fiber coupled laser diodes.

In this paper, we demonstrate the continuous-wave and acousto-optical Q-switched performance of diode-pumped slab Ho:(Sc0.5Y0.5)2SiO5 (Ho:SYSO) laser at 2.1 µm for the first time. Two 1.91-µm laser diodes were used to pump the Ho:SYSO crystal. With a wing-pumping structure, at absorbed pump power of 44.7 W, the continuous wave slab Ho:SYSO laser produced 20.7 W maximum output power at 2097.9 nm, resulting in a slope efficiency of 53.1% with respect to the absorbed pump power. In the Q-switched regime, the slab Ho:SYSO laser produced up to 3.4 mJ pulse energy with 20 ns minimum pulse width at pulse repetition frequency of 5 kHz, corresponding to a peak power of 170 kW.

Resonantly pumped high efficiency Ho:GdTaO4 laser.

We demonstrate a continuous-wave 2.1-µm laser with a new Ho:GdTaO4 crystal pumped by a 1940.3-nm Tm fiber laser at room temperature. The maximum output power of 11.2 W at 2068.39 nm was achieved, corresponding to a slope efficiency of 72.9%. Moreover, the beam quality factor was measured to be about 1.4 at the maximum output level.

Resonantly pumped high efficiency Ho:GdTaO4 laser: erratum.

An erratum is presented to correct the wrong picture in our paper.

High-beam-quality operation of a 2 µm passively Q-switched solid-state laser based on a boron nitride saturable absorber.

Boron nitride (BN) nanosheets were used as the material sources which were coated on a calcium fluoride mirror to achieve a saturable absorber (SA). A passively Q-switched solid-state laser at 2000.5 nm was demonstrated with a Tm,Ho:YAlO3 (Tm,Ho:YAP) crystal and a SA based on BN. An average output power of 650 mW was obtained with a minimum pulse width of 6.3 µs at the pulsed repetition frequency of 41.7 kHz, corresponding to a per pulse energy of 13 µJ. The beam quality factor was measured to be Mx2=1.06 and My2=1.07 at the maximum output power.

Quantitative assessment of enterprise environmental risk mitigation in the context of Na-tech disasters.

As an important causative factor of environmental accidents, natural disasters have recently received much attention for environmental risk assessment. Typhoons are one of the most frequent natural disasters in the northern Pacific Ocean and South China Sea and cause enormous damage to agriculture, daily livelihood, and industry. In this study, an environmental risk assessment for industrial enterprises is conducted when considering typhoon disasters. First, a Na-tech (natural hazard triggering technological disasters) environmental risk assessment index system with the aid of an analytic hierarchy process and fuzzy evaluation model (ERA-FAM) is developed to explore the major determinants related to risk level. The impact of typhoon disasters on environmental risk from chemical enterprises is discussed using a comparative analysis of risk levels with and without typhoon disaster scenarios. A chemical plant located in Zhejiang, China, is selected as a case study using this methodology. Three hypothetical scenarios are assumed, based on actual situations, to explore the impact of various factors on environmental risk. The results demonstrate that production factors and surrounding environmental conditions are the most sensitive factors for typhoon disasters, while emergency preparation is most important for reducing environmental risk. The influence of typhoons on environmental risk values is much higher for enterprises with imperfect management and vulnerable water risk receptors. Incorporating disaster management into environmental risk management will aid in developing strategies and policies for environmental risk mitigation and risk reduction practices.