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The newly reclaimed soil is an important reserve land resource, while it faces challenges such as poor water retention and low fertility. Therefore, it requires improvement through the use of soil amendments. Attapulgite (ATP) is abundant in northwest China with excellent properties and can be used as an amendment for newly reclaimed soil. The effects of ATP and its addition rate on infiltration and evaporation characteristics in newly reclaimed soil were studied by experiments and model simulation. Three addition gradients (2%, 4%, and 6%) were set in this study, and no ATP addition was used as a control (CK). The results show that ATP treatment prolonged the infiltration duration, reduced the wetting front migration distance, and reduced the accumulated evaporation. Both the Philip model and the Kostiakov model can accurately describe the infiltration process of newly reclaimed soil with ATP addition; the soil evaporation process can be fitted well with the Rose model. In this study, ATP addition affected both sorptivity and the stable infiltration rate of the reclaimed soil. During the evaporation, the soil evaporation effect was inversely proportional to the addition rates of ATP, and the ATP addition rate at 2% had the best effect on reducing soil evaporation. In summary, the ATP addition was beneficial top soil infiltration and evaporation, thus improving the poor water retention of newly reclaimed land and is a reasonable choice for efficient construction of new reclaimed land.

Rationale and objectives: Radiomic models based on normal-resolution (NR) computed tomography angiography (CTA) images can fail to distinguish between symptomatic and asymptomatic carotid atherosclerotic plaques. This study aimed to explore the effectiveness of a deep learning-based three-dimensional super-resolution (SR) CTA radiomic model for improved identification of symptomatic carotid atherosclerotic plaques. Materials and methods: A total of 193 patients with carotid atherosclerotic plaques were retrospectively enrolled and allocated into either a symptomatic (n = 123) or an asymptomatic (n = 70) groups. SR CTA images were derived from NR CTA images using deep learning-based three-dimensional SR technology. Handcrafted radiomic features were extracted from both the SR and NR CTA images and three risk models were developed based on manually measured quantitative CTA characteristics and NR and SR radiomic features. Model performances were assessed via receiver operating characteristic, calibration, and decision curve analyses. Results: The SR model exhibited the optimal performance (area under the curve [AUC] 0.820, accuracy 0.802, sensitivity 0.854, F1 score 0.847) in the testing cohort, outperforming the other two models. The calibration curve analyses and Hosmer–Lemeshow test demonstrated that the SR model exhibited the best goodness of fit, and decision curve analysis revealed that SR model had the highest clinical value and potential patient benefits. Conclusions: Deep learning-based three-dimensional SR technology could improve the CTA-based radiomic models in identifying symptomatic carotid plaques, potentially providing more accurate and valuable information to guide clinical decision-making to reduce the risk of ischemic stroke.

An actively Q-switched all-solid-state YVO4 Raman laser, which used a 885-nm side-pumped Nd:YAG laser as the fundamental wavelength and delivered yellow output, is demonstrated. An in-band pump scheme is adopted to mitigate the thermal effects in the laser crystal and a Z-shaped laser cavity is used to compensate thermal lensing further. By intracavity frequency doubling of the Stokes wave with KTP crystal, 13.7-W yellow output at a wavelength of 588 nm, with a pulse repletion frequency of 10 kHz, was obtained under a diode pump power of 233 W. Additionally, single-pulse energy was 1.37 mJ with the pulse-width of 12.5 ns, corresponding to a peak power of 110 kW.

The linear demodulation range and background noise of the Michelson interferometer system are investigated with a laser phase noise measurement system. We have theoretically and experimentally analyzed the performance of the interferometer system by changing the frequency modulation amplitude of the laser and the optical path difference (OPD) of the interferometer, respectively. It is shown that the linear demodulation range of the Michelson interferometer system is finite, which depends on the parameters of the system, such as the sample frequency, the delay time between two interferometer arms, and the system bandwidth. Furthermore, the experimental results indicate that the background noise of the interferometer system can be reduced by using a sufficiently long OPD so that the smaller true phase information can be detected with the demodulation system. The parameters of the measurement system could be optimized to satisfy the demand of the phase demodulation with different levels, which is of great significance for the phase monitoring interrogator, such as fiber-optical interferometer sensors and distributed acoustic sensors.

Ureteral reconstruction with autologous tissue grafts is often limited by tissue availability and donor site morbidity. This study investigates the performance of acellular, bi-layer silk fibroin (BLSF) scaffolds in a porcine model of ureteroplasty. Tubular ureteroplasty with BLSF grafts in combination with transient stenting for 8 weeks was performed in adult female, Yucatan, mini-swine (N = 5). Animals were maintained for 12 weeks post-op with imaging of neoconduits using ultrasonography and retrograde ureteropyelography carried out at 2 and 4 weeks intervals. End-point analyses of ureteral neotissues and unoperated controls included histological, immunohistochemical (IHC), histomorphometric evaluations as well as ex vivo functional assessments of contraction/relaxation. All animals survived until scheduled euthanasia and displayed mild hydronephrosis (Grades 1-2) in reconstructed collecting systems during the 8 weeks stenting period with one animal presenting with a persistent subcutaneous fistula at 2 weeks post-op. By 12 weeks of scaffold implantation, unstented neoconduits led to severe hydronephrosis (Grade 4) and stricture formation in the interior of graft sites in 80% of swine. Bulk scaffold extrusion into the distal ureter was also apparent in 60% of swine contributing to ureteral obstruction. However, histological and IHC analyses revealed the formation of innervated, vascularized neotissues with a-smooth muscle actin+ and SM22α+ smooth muscle bundles as well as uroplakin 3A+ and pan-cytokeratin + urothelium. Ex vivo contractility and relaxation responses of neotissues were similar to unoperated control segments. BLSF biomaterials represent emerging platforms for tubular ureteroplasty, however further optimization is needed to improve in vivo degradation kinetics and mitigate stricture formation.

Previous studies have shown that amnestic mild cognitive impairment (aMCI) involves in the morphological abnormalities of multiple regions, including cortical thickness, sulcus depth, surface area, gray matter volume, jacobian metric and average curvature. All the measures have unique neuropathological and genetic meanings. However, most existing methods simply average or concatenate these measures when constructing the classifiers, which may include redundant information and ignore the relationships among them. In this study, we treat each measure as a task in our multitask learning framework. Considering the actual situation that we do not know the correlation between tasks in advance, we use a robust multitask feature learning (rMTFL) method to select a group of features among correlated measures and provide additional information by identifying outlier tasks at the same time. Then, we train several SVM classifiers and for each measure, we input the selected features into the corresponding SVM classifier. Finally, we use an ensemble classification strategy to combine the results of these classifiers based on the accuracy to make the final prediction. We use the leave-one-out cross-validation to evaluate our proposed method with 46 amnestic mild cognitive impairment (aMCI) and 52 normal controls (NC). The results show that rMTFL algorithm is superior to the group lasso method and average curvature is the outlier task based on multidimensional surface measures.

Here, we present a thermal load model of a Nd:YVO4 laser under dual-wavelength pumping. Pumping the gain medium with both traditional and in-band pump light in adjustable proportion, the design takes full advantage of high efficiency and low heat of the two pump schemes, and the thermal load can be controlled actively, thus being capable of achieving optimal laser performance allowed under certain restrictions. The range of optimal proportion under different restrictions is discussed. Experimental results of a Nd:YVO4 laser under 808-nm and 880-nm dual-wavelength pumping validated the theoretical analysis.

In order to release the capability restriction of the North–South transmission channels in the 500 kV power grid of Fujian Province, this article studies the application of unified power flow controller (UPFC) to improve the transmission capability under steady-state security restriction with N−1 principle. On the basis of analysis of principle and structure of UPFC, a simplified equivalent model of UPFC is constructed and used in BPA simulation software. The optimal installation scheme and the minimal capacity required of UPFC are determined by comparing the results of power flow calculation in various schemes. The research result shows that the application of UPFC can effectively reduce the N−1 overload problem of the North–South transmission channels, and has a great economic advantage over the traditional solution. Finally, based on the technical and economic analysis, this study puts forward suggestions on the construction of UPFC in the Fujian 500 kV power grid.

An analytical model for analyzing multi-channel intracavity spectroscopy technology (ICST) is established based on rate equations of Er-doped fiber laser. With the consideration of the amplified spontaneous emission, how the mode competition influences the iterative process for a stable output is analyzed. From the perspective of iterative times, the sensitivity-enhanced mechanism of the ICST is explained. Moreover, the theoretical modeling is employed to analyze the role that the mode-competition effect plays in switching the sensing channel automatically. It is demonstrated that, owing to the mode-competition effect in the laser cavity, the modulation of the cavity loss can be used to tune the sensing channel automatically. Furthermore, our proposed theoretical modeling is verified using a multi-channel ICST sensing system. It is indicated that the calculated estimates agree well with those data from the experimental absorption spectra. The principle will play a significant role in realizing the multiplexing of ICST.

An efficient Q-switched eye-safe Nd:YVO4 self-Raman laser, which we believe to be the first one in-band pumped at 914 nm, is presented, and 2.58 W of 1525-nm Stokes output was generated under the absorbed pump power of 10.2 W with a high repetition rate of 100 kHz, corresponding to a conversion efficiency of 25.3%. The optical efficiency with respect to incident pump also reached 16.4%. Influences of crystal temperature and dopant concentration on the performance of the eye-safe self-Raman laser were experimentally investigated.

With this stringent definition, it is sobering to realize that even in the best of hands, 25% to 42% of patients will have postoperative stone remnants resulting in reintervention within 2 years in nearly a third of patients. Radiographs may miss stones in 30% to 40% of patients while ultrasonography misses up to 27% of stone remnants. Thirty-eight patients were identified during that period who reported active use of PPS, the 6 patients constituting 16% of this group. [Extracted from the article]

CO2 reforming of CH4 was studied over a magnetoplumbite-type hexaaluminate La0.8Pr0.2NiAl11O19 catalyst, which showed very high activity for over 300 h without deactivation at 1023 K. This catalyst showed good resistance to carbon deposition, which in this reaction and in CH4 decomposition was investigated by means of XPS and TEM. It is suggested that nano-tube-like carbon is an intermediate in this reaction and a spillover of carbon from crystalline Ni onto the hexaaluminate oxide occurred during the reaction. [ABSTRACT FROM AUTHOR]

We proposed and experimentally demonstrated the generation of high-power 1176 nm Stokes wave by frequency shifting of a 885 nm diode-side-pumped Nd:YAG laser using a YVO4 crystal in a Z-shaped cavity configuration. Employing the 885 nm diode-side-pumped scheme and the Z-shaped cavity, for the first time to our knowledge, we realized the thermal management effectively, achieving excellent 1176 nm Stokes wave consequently. With an incident pump power of ~190.0 W, a maximum average output power of 16.7 W was obtained at the pulse repetition frequency of 10 kHz. The pulse duration and spectrum linewidth of the Stokes wave at the maximum output power were 20.3 ns and ~0.08 nm, respectively. [ABSTRACT FROM AUTHOR]

A frequency-doubled Nd:YVO4 self-Raman laser in-band pumped by an 878.7 nm wavelength-locked laser diode (LD) is demonstrated, with the purpose of improving the pump absorption of in-band pumping and thus enhancing optical efficiency. 2.64 W average output power at 588 nm is obtained under incident LD power of 9.7 W, corresponding to an optical efficiency of 27.2%. The results of control experiments show that in-band pumping leads to higher conversion efficiency of a self-Raman laser than does traditional pumping. Moreover, the application of a wavelength-locked LD further improves optical efficiency significantly. [ABSTRACT FROM AUTHOR]