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Spin-polarization effects of an ultrarelativistic electron beam head-on colliding with an ultraintense two-color laser pulse are investigated comprehensively in the quantum radiation-dominated regime. We employ a Monte Carlo method, derived from the recent work of [Phys. Rev. Lett. {\bf 122}, 154801 (2019)], to calculate the spin-resolved electron dynamics and photon emissions in the local constant field approximation. We find that electron radiation probabilities in adjacent half cycles of a two-color laser field are substantially asymmetric due to the asymmetric field strengths, and consequently, after interaction the electron beam can obtain a total polarization of about 11\% and a partial polarization of up to about 63\% because of radiative spin effects, with currently achievable laser facilities, which may be utilized in high-energy physics and nuclear physics. Moreover, the considered effects are shown to be crucially determined by the relative phase of the two-color laser field and robust with respect to other laser and electron beam parameters., 7 pages, 7 figures

The impact of the carrier-envelope phase (CEP) of a long relativistic tightly focused laser pulse on the dynamics of a counterpropagating electron beam has been investigated theoretically in the, so-called, electron reflection regime. Our semiclassical Monte Carlo simulations show that the electrons are reflected at the rising edge of the laser pulse due to the ponderomotive force of the focused laser beam, and an asymmetric electron-momentum distribution emerges along the laser polarization direction, which sensitively depends on the CEP of the driving laser pulse for weak radiative stochasticity effects. The CEP signatures can be determined in the electron-momentum distribution at laser intensities of the order or larger than ${10}^{19}\phantom{\rule{0.16em}{0ex}}\mathrm{W}/{\mathrm{cm}}^{2}$ and for the pulse lengths up to 10 cycles. The CEP detection resolution is proportional to the electron beam density and can achieve approximately $0.{1}^{\ensuremath{\circ}}$ at an electron density of about ${10}^{15}\phantom{\rule{4pt}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$. The method is applicable for currently available ultraintense laser facilities with the laser peak power ranging from tens of terawatt to multipetawatt.

The impact of stochasticity effects (SEs) in photon emissions on the proton energy spectra during laser-plasma interaction is theoretically investigated in the quantum radiation-dominated regime, which may facilitate SEs experimental observation. We calculate the photon emissions quantum mechanically and the plasma dynamics semiclassically via two-dimensional particle-in-cell simulations. An ultrarelativistic plasma generated and driven by an ultraintense laser pulse head-on collides with another strong laser pulse, which decelerates the electrons due to radiation-reaction effect and results in a significant compression of the proton energy spectra because of the charge separation force. In the considered regime the SEs are demonstrated in the shift of the mean energy of the protons up to hundreds of MeV. This effect is robust with respect to the laser and target parameters and measurable in soon available strong laser facilities.

Dynamics of an electron beam head-on colliding with an ultraintense focused ultrashort circularly polarized laser pulse are investigated in the quantum radiation-dominated regime. Generally, the ponderomotive force of the laser fields may deflect the electrons transversely, to form a ring structure in the cross section of the electron beam. However, we find that when the Lorentz factor of the electron $\ensuremath{\gamma}$ is approximately one order of magnitude larger than the invariant laser field parameter $\ensuremath{\xi}$, the stochastic nature of the photon emission leads to electron aggregation abnormally inwards to the propagation axis of the laser pulse. Consequently, the electron angular distribution after the interaction exhibits a peak structure in the beam propagation direction, which is noticeably distinguished from the ``ring'' structure of the distribution in the classical regime and, therefore, can be recognized as a proof of the fundamental quantum stochastic nature of radiation. The stochasticity signature is robust with respect to the laser and electron parameters and observable with current experimental techniques.

The motion of two interactional solitons is investigated in nonlinear media with an exponential nonlocal response. A differential equation describing the motion trajectories of soliton center is proposed. Some numerical simulations are performed to illustrate the characteristics of the motion trajectories. The results show that the trajectories always oscillate periodically. However, if the two solitons are launched with a relative inclined angle which is larger than a critical value, they do not collide any more but diverge from each other. The critical angle is also given.

The generation of highly polarized high-energy brilliant γ-rays via laser–plasma interaction is investigated in the quantum radiation-reaction regime. We employ a quantum electrodynamics particle-in-cell code to describe spin-resolved electron dynamics semiclassically and photon emission and polarization quantum mechanically in the local constant field approximation. As an ultrastrong linearly polarized (LP) laser pulse irradiates a near-critical-density (NCD) plasma followed by an ultrathin planar aluminum target, the electrons in the NCD plasma are first accelerated by the driving laser to ultrarelativistic energies and then collide head-on with the laser pulse reflected by the aluminum target, emitting brilliant LP γ-rays via nonlinear Compton scattering with an average polarization of about 70% and energy up to hundreds of MeV. Such γ-rays can be produced with currently achievable laser facilities and will find various applications in high-energy physics and laboratory astrophysics.

Generation of high-flux vortex γ -ray pulses is investigated in the interaction of ultraintense Bessel–Bessel laser bullets colliding head-on with ultrarelativistic electron bunches in the quantum radiation-dominated regime. In the simulations, a semiclassical Monte–Carlo method is used, based on the radiation probabilities in the local constant field approximation, to describe the electron motion and emission of radiation. Characteristics of the driving laser pulse (orbital angular momentum and nondiffracting spatial and temporal structures) are transferred to the emitted γ rays by nonlinear Compton scattering.

Gamma-ray beams with a large angular momentum may affect astrophysical phenomena, which calls for appropriate earth-based experimental investigations. For this purpose, we investigate the generation of well-collimated γ-ray beams with a very large orbital angular momentum using nonlinear Compton scattering of a strong laser pulse of twisted photons at ultrarelativistic electrons. Angular momentum conservation among absorbed laser photons, quantum radiation, and electrons is numerically demonstrated in the quantum radiation-dominated regime. We point out that the angular momentum of the absorbed laser photons is not solely transferred to the emitted γ photons, but due to radiation reaction shared between the γ photons and interacting electrons. The efficiency of the angular momentum transfer is optimized with respect to the laser and electron beam parameters. The accompanying process of electron-positron pair production is furthermore shown to enhance the orbital angular momentum gained by the γ-ray beam.

Sensory navigation device is an important trend in the field of machine learning and data science. Nowadays, more and more sensory navigation devices are built for blind people. The core of such sensory navigation devices for blind people usually is implemented by an Image Recognition Method. To build an image recognition model, many tools and online machine learning platforms are proposed. However, these tools or platforms are not able to completely satisfy the requirements for sensory navigation device. To build a sensory navigation device with satisfying requirements for blind people, an ability of reducing the cost of model training and a capability of user-centric image recognition are the two main issues. Therefore, to address the above issues, we propose a novel approach, namely, DLSNF (Deep-Learning-based Sensory Navigation Framework). Our proposed DLSNF is built based on the YOLO architecture to deal with the reducing cost of model training and NVIDIA Jetson TX2 to take the user-centric image recognition into account. Based on our proposed DLSNF, the real-time image recognition can be trained well and conduct a sensory navigation to help blind people. At the same time, the train model is embedded in NVIDIA Jetson TX2 which is the fastest, most power-efficient embedded AI computing device. For the experiments, we evaluated our proposed DLSNF with a real-world dataset consisting of 4,570 images collected by part-time workers. The extensive experimental results show that our proposed DLSNF more effectively and efficiently beyond the existing baselines.

Signatures of stochastic effects in the radiation of a relativistic electron beam interacting with a counterpropagating superstrong short focused laser pulse are investigated in a quantum regime when the electron’s radiation dominates its dynamics. We consider the electron-laser interaction at near-reflection conditions when pronounced high-energy gamma-ray bursts arise in the backward-emission direction with respect to the initial motion of the electrons. The quantum stochastic nature of the gamma-photon emission is exhibited in the angular distributions of the radiation and explained in an intuitive picture. Although, the visibility of the stochasticity signatures depends on the laser and electron beam parameters, the signatures are of a qualitative nature and robust. The stochasticity, a fundamental quantum property of photon emission, should thus be measurable rather straightforwardly with laser technology available in near future.

We demonstrate the feasibility of generation of bright ultrashort gamma-ray pulses and the signatures of stochastic photon emission via the interaction of a relativistic electron bunch with a counterpropagating tightly-focused superstrong laser beam in the quantum-radiation-dominated regime. We consider the electron-laser interaction at near-reflection conditions when pronounced high-energy gamma-ray bursts arise in the backward-emission direction with respect to the initial motion of the electrons. The Compton scattering spectra of gamma-radiation are investigated using a semiclassical description for the electron dynamics in the laser field and a quantum electrodynamical description for the photon emission. We demonstrate the feasibility of ultrashort gamma-ray bursts of hundreds of attoseconds and of dozens of megaelectronvolt photon energies in the near-backwards direction of the initial electron motion. The tightly focused laser field structure and radiation reaction are shown to be responsible for such short gamma-ray bursts, which are independent of the durations of the electron bunch and of the laser pulse. Moreover, the quantum stochastic nature of the gamma-photon emission is exhibited in the angular distributions of the radiation and explained in an intuitive picture. Although, the visibility of the stochasticity signatures depends on the laser and electron beam parameters, the signatures are of a qualitative nature and robust. The stochasticity, a fundamental quantum property of photon emission, should thus be measurable rather straightforwardly with laser technology available in near future.

The impact of stochasticity effects (SEs) in photon emissions on the proton energy spectra during laser-plasma interaction is theoretically investigated in the quantum radiation-dominated regime. We calculate the photon emissions quantum mechanically and the plasma dynamics semiclassically via two-dimensional particle-in-cell simulations. An ultrarelativistic plasma generated and driven by an ultraintense laser pulse head-on collides with another strong laser pulse, which decelerates the electrons due to radiation-reaction effect and results in a significant compression of the proton energy spectra because of the charge separation force. In the considered regime the SEs are demonstrated in the shift of the mean energy of the protons up to hundreds of MeV. This effect is robust with respect to the laser and target parameters and measurable in soon available strong laser facilities.

In this study, we sequenced plastid DNA to investigate the interspecific relationships of Stemona species . In total, 34 individuals from 23 populations were studied, covering the geographical range of Stemona in China plus eight individuals from Indonesia. Our results show that seven Stemona species cluster into three major clades; S. parviflora is closest to S. javanica of the species studied; it is reasonable to treat S. shandongensis as a synonym of S. sessilifolia , whereas S. japonica is close to S. sessilifolia ; the geographically widespread species S. tuberosa possesses a high degree of differentiation and contains three subgroups.

The real-time monitoring technologies of smart civil structure based on detecting picometer-scale wavelength shift of fiber Bragg grating (FBG), including the wavelength demodulation technology of FBG, are researched extensively at home and abroad. In the paper, using the technologies of wavelength division multiplex (WDM) and time division multiplex (TDM), fiber Bragg grating (FBG) sensor network was built for monitoring smart structure health condition. Based on SOPC (System on Programmable Chip) technology and fiber comb filter, a high-speed and high-precision wavelength demodulation scheme of FBG sensor network was proposed. The optical system and hardware circuit for demodulation system were designed specifically. To improve the accuracy of demodulation system of FBG, a constant temperature channel of the demodulation system connected with a fiber comb filter, which offered reference points to calibrate the Bragg grating center wavelength. Based on 32-bit soft-core processor NoisⅡ, the embedded system collected and processed the photoelectric signal voltage transformed to rectangular voltage pulse. The upper computer displayed dynamically the FBG wavelength demodulation process and calibrated the Bragg grating center wavelength. The experiments of FBG wavelength demodulation and health monitoring of smart structural embedded fiber Bragg gratings were done. Experimental results show that, the FBG wavelength demodulation method can be used to demodulate the FBG wavelength with high speed and high precision (± 2 pm), which can be used extensively in large-scale multipoint monitor engineering, and the strains of the smart structure can be measured accurately.

In this paper, the interactional behaviors of anomalous vortex beams in highly nonlocal media are investigated. An analytical expression describing the interaction is given, and some numerical simulations are carried out to illustrate the interactional characteristics. It is found that two interactional anomalous vortex beams always attract each other, and their evolution is periodical. The influence of different relative phases between two anomalous vortex beams on their interaction is presented in details. Keywords: Interaction, Anomalous vortex beam, Nonlocal media

The sequence of aeolian red clay and loess deposited in northern China since late Neogene is an ideal palaeoclimate recorder. A profile consisting of loess, lacustrine deposits and red clay was found at Wuqi County in the northern Chinese Loess Plateau. Preliminary investigations were carried out on the typical Tufosi section in order to provide the age constraints of the lacustrine deposits (namely the Wuqi paleolake). Rock magnetic results demonstrate that the magnetic carriers of the characteristic remanent magnetization of lacustrine deposits are mainly magnetite and hematite. The correlation between the magnetic polarity sequence of the Tufosi section and geomagnetic polarity time scale is very well. The age of the bottom of the section is 4.28 Ma B. P. approximately. The Wuqi paleolake formed at about 3.0 Ma B. P. and died out around 1.2 Ma B. P. The regional environment became colder and drier during this period as implied by the variations of lithology, magnetic susceptibility, grain size and sedimentation rates. The evolution history of the Wuqi paleolake can be divided into three stages: the paleolake was formed during the period of 3.0~2.5 Ma B. P. and the water body was relatively deep; the lake became shallow markedly as the result of paleoclimate change during 2.50~2.05 Ma B. P.; during 2.05~1.20 Ma B. P., reduction of the water body led to the extinction of the lake. Climatic deterioration in this region around 1.2 Ma B. P. was the main reason for the end of the Wuqi paleolake. Besides, the headward erosion of the North Luo River caused by regional tectonism was probably a factor, too.

Background We investigated the difference between left ventricular (LV) hypertrophy caused by primary hypertension and physiological LV hypertrophy in athletes as seen in left atrial (LA) function by real-time tri-plane strain rate imaging. Hypothesis A real-time tri-plane imaging technique using the same phase of the same cardiac circle was used to synchronously demonstrate the section of apical 4-chamber, 2-chamber, and apical left ventricle long axis. Methods We measured standard Doppler echocardiographic quantitative analysis and the strain rate peak values of each LA wall in the systolic phase, in the early stage of diastole, and in the advanced stage of diastole and made a comparison of these values. Results The alteration of configuration and function of the left atrium in hypertensive patients is an early sign of the myocardial damage caused by hypertension. Strain rate imaging could sensitively reflect LA function changes in the early stages of hypertension. While physiological, myocardial hypertrophy is a benign reaction, LA function is significantly different from that of hypertension. Conclusions Real-time tri-plane strain rate imaging techniques could simultaneously analyze 3 sections, which shortens scanning time and depletes the influence of variations of different cardiac cycles on quantitative analysis of local myocardial segments of the left atrium. This would improve the comparability of myocardial movement of different segments so that we could more comprehensively and accurately evaluate the systolic and diastolic function of the left atrium in primary hypertension and physiological LV hypertrophy in athletes. Copyright © 2009 Wiley Periodicals, Inc.

Objectives: To analyze the risk factors for systemic inflammatory response syndrome (SIRS) after percutaneous nephrolithotomy (PCNL) and to quantitatively predict the probability of SIRS after PCNL. Methods: Medical records on 209 patients who underwent PCNL were retrospectively analyzed. The χ2 test, the t-test and a logistic regression model were used to identify key risk factors of SIRS after PCNL. A predictive equation was then formulated to assess the risk of SIRS according to the results from the logistic model. Subsequently, the accuracy of the equation by calculating sensitivity, specificity, overall correct percentage, and positive and negative predictive values was tested. Results: The incidence of SIRS after PCNL was 23.4%. The key risk factors for SIRS following PCNL were: the number of tracts, receipt of a blood transfusion, stone size, and presence of pyelocaliectasis. Other factors added no independent risk to the development of SIRS. The calculated values for sensitivity, specificity, overall percentage correct, positive predictive value and negative predictive value were 44.9%, 95.0%, 83.3%, 73.3%, and 84.9%, respectively. Conclusions: Number of tracts, receipt of a blood transfusion, stone size and presence of pyelocaliectasis are identified as the key risk factors for SIRS after PCNL. The predictive equation allows for an individualized and quantitative assessment of the probability of SIRS after PCNL.

To compare the efficacy and safety of tubeless percutaneous nephrolithotomy (tubeless-PCNL) and ureteroscopic lithotripsy (URL) in treatment of impacted upper-ureteral calculi ≥ 1.5 cm in size.Patients with ureteral stones sized ≥ 1.5 cm and lodged above the fourth lumbar vertebra who were treated between September 2009 and July 2013 in Peking University People's Hospital were retrospectively analyzed. In the study, 182 patients underwent tubeless-PCNL or URL treatment respectively, and the operation success rates were compared. The duration of operation, intraoperative blood loss(average hemoglobin decrease), complications, mean hospital stay and residual stone rates were also compared.Fifty-four patients underwent tubeless-PCNL treatment,the average stone size was (1.9 ± 0.4) cm,nephrostomy tubes were placed in two patients,and the operation success rate was 96.3%(52/54). In the rest of the 52 patients,and the mean operation time was (30.1 ± 14.8) minutes with an average postoperative hemoglobin decrease of (10.2 ± 6.1) g/L, and the mean hospital stay was (3.0 ± 1.4) days. Only one of the patients had residual fragments (2%). The main complications included minor perirenal hematoma in 1 patient, fever in 2 patients,elevated blood WBC in 11 patients,and analgesics requirement in 3 patients. In the study, 128 patients were treated with URL,the average stone size was (1.7 ± 0.3) cm. 19 procedures failed,and 10 patients were converted to PCNL,extracorporeal shock wave lithotripsy was executed subsequently after double-J stent placement in 5 patients,and migration of calculi or stone fragments happened in 4 patients. The mean operative time was (51.3 ± 25.5) minutes for the remaining 109 patients with a hemoglobin reduction of (5.2 ± 7.2) g/L. The mean hospital stay was (2.9 ± 1.3) days, and residual stones were found in 13 of the 109 patients (11.9%). The main complications included fever in 3 patients, elevated blood WBC in 42 patients, analgesics requirement in 13 patients because of pain in the urethra or flank. The size of the stones between the two group didn't show significant difference,but the success rate of the tubeless-PCNL procedure was significantly higher. Except that hemoglobin decrease was slightly higher in the tubeless-PCNL group,the mean operative time, the rate of residual stones and rate of complications of the tubeless-PCNL group were lower significantly.Treating stones above 4th lumbar vertebra larger than 1.5 cm were challenging. It is difficult to treat these stones with URL because of a high probability to fail, but on the contrary, tubeless-PCNL was more likely to be performed successfully. For surgeons experienced with the PCNL technology, treating stones ≥ 1.5 cm with tubeless-PCNL procedure may turn out to be more efficient and with a higher operation success rate, and the risk of complications was lower without lengthening the postoperative hospital stay.

A vacuum auto-resonance accelerator scheme for electrons, which employs terahertz radiation and currently available magnetic fields, is suggested. Based on numerical simulations, parameter values, which could make the scheme experimentally feasible, are identified and discussed.

In this paper, we focus on the on-axis intensity evolutions of hollow beams in nonlinear media with a high nonlocality. It is found that, the evolutions of on-axis intensity with different beam powers are always periodic during propagation, whereas, depending on different beam powers, the evolution curves of on-axis intensity in each period may exhibit themselves as three different types, namely, a concave, a platform, or a convex shape. The critical power, the extreme values of on-axis intensity and their corresponding positions are all given analytically. Keywords: Nonlocal nonlinearity, Beam propagation, Hollow beams, On-axis intensity

To find the causes of retrograde intrarenal surgery (RIRS) failure in renal calculi treatment and evaluate the efficacy and morbidity of remedial measures.All the patients with renal stone who had undergone RIRS in the last two years were reviewed and the failure cases screened out according to operating records.Within the 132 patients, 19 RIRS procedures failed. The causes of failure included ureteral (42.1%), intrarenal (36.8%), stone (10.5%) and operating reason (5.3%).The caculi of 11 patients were cleaned by remedial percutaneous nephrolithotomy (PCNL), seven patients had secondary RIRS one week later, and only one patient left the renal stone for observation and dietary regulation. Sixteen patients were stone-free after remedial treatment and the complications included ureteral perforation in one case and high fever in 4 cases.The main causes of RIRS failure are ureteral incompatibility and intrarenal disadvantageous anatomy. PCNL and secondary RIRS are the effective remedial measure after RIRS failure.

To investigate the bacteriology and drug sensitivity of upper urinary tract calculi patients, and to provide information for choosing suitable antibiotics.In the study, 21 patients who suffered from lithiasis in upper urinary tract and required an emergency drainage for acute obstruction and infection were the "acute group"; 64 patients with calculi in upper urinary tract and accompanied with no infectious symptoms were the "common group". The bacteriology and drug sensitivity of the two groups were investigated.Gram-negative bacteria infected the most common of upper urinary tract calculi patients with infection, accounting for 71.4% in the acute group and 65.7% in the common group, among which Escherichia coli were the predominant ones (35.7% in the acute group and 32.9% in the common group). No difference was found between these two groups in bacterial distribution (P0.05). Although the average drug resistance rate of Gram-negative bacteria in the acute group was higher than that in the common group, it revealed no significant difference (P0.05). The drug resistance rate to semisynthetic penicillin, cefuroxime and ceftriaxone were more than 50%, 60%, and 50%, respectively. Quinolones, such as ciprofloxacin and levofloxacin, got a 45% drug resistance. Aminoglycoside, carbapenema were sensitive to Gram-negative bacteria. Cefoperazone/sulbactam and piperacillin/tazobactam were more effective than ceftriaxone and piperacillin, respectively.There was no significant difference between upper urinary tract calculi patients with acute infection and common infection in bacteriology and drug sensitivity. Semisynthetic penicillin, the second generation of cephalosporin and quinolone were no longer the good choices of empirical use. Antibiotics combined with β-lactamase inhibitors would be an ideal empirical therapeutic choice.

To investigate the risk factors of systemic inflammatory response syndrome (SIRS) after one-phase treatment for apyrexic calculous pyonephrosis by percutaneous nephrolithotomy (PCNL).Clinical data of consecutive apyrexic calculous pyonephrosis patients who underwent one-stage PCNL from January 2008 to December 2013 were analyzed retrospectively. The data collected included white blood cells in urine analysis before surgery, midstream urine culture, preoperative renal function, using antibiotics time before surgery, operative time, the number of tracts, intraoperative irrigation peak flow, blood transfusion, and stone composition. Chi-square, t test and Logistic regression methods were used for analysis of each factor and SIRS.A total of 182 patients were enrolled in this study and 38 patients developed SIRS (20.88%). There were no statistically significant differences among white blood cells in urine analysis (P = 0.483), urine culture positive (P = 0.136), and struvite (P = 0.324) in terms of the incidence of postoperative SIRS. Multivariate Logistic regression model indicated that risk factors of SIRS for apyrexic calculous pyonephrosis after one-phase PCNL were renal insufficiency (OR = 5.41, 95% CI 1.84 to 22.64, P = 0.014), operative time (OR = 1.01, 95% CI 1.00 to 1.02, P = 0.024), operative tracts (OR = 3.37, 95% CI -1.92 to 32.55, P = 0.077), intraoperative irrigation peak flow ≥500 mL/min (OR = 45.87,95% CI 4.39 to 231.68, P = 0.007), and blood transfusion (OR = 5.98, 95% CI 1.12 to 46.66, P = 0.043). The protective factor was antibiotics use for more than 3 days (OR = 0.34, 95% CI -3.92 to 12.55, P = 0.047).The incidence of SIRS after one-phase PCNL treatment for apyrexic calculous pyonephrosis was similar to that of other patients. It is relatively safe and reliable to do this. Preoperative antibiotics should be used for more than 3 days before surgery. Careful manipulation is needed to avoid blood transfusion. It is better to shorten the operative time and to reduce multiple tracts operation. Particularly, irrigation peak flow ≥500 mL/min should be avoided in the circumstance of bleeding or turbid urine.

To investigate the diagnosis and treatment of renal pelvic tumor combined with renal urinary calculi and hydronephrosis.Five patients with renal pelvic tumor who underwent relief of the upper urinary obstruction were reviewed.One of the cases lost the opportunity of surgical therapy when pelvic tumor was detected at the advanced stage, and the other 4 cases had received surgery and were followed up.As pelvic tumor progresses rapidly after the renal blood flow is improved, and renal urinary calculi with hydronephrosis relieved; the patients with renal pelvic tumor need early diagnosis, aggressive treatment and close follow-up.

We have studied the electron acceleration by a tightly focused cylindrical vector Gaussian beam. Different from the Lax series field, cylindrical vector Gaussian beams are vector-beam solutions of Maxwell's equations and its focusing property can be numerically analyzed by the Richards–Wolf vectorial diffraction theory. Field differences exist between the cylindrical vector Gaussian beam and the Lax series field. The cylindrical vector Gaussian beam increases the asymmetry of the electromagnetic fields, which is more beneficial to the electron acceleration. When the beam waist falls down to the order of the wavelength, the high laser intensity zone is more proper to define the reflection, capture and transmission conditions of the electrons. The injection energy and the injected angle of the electron and the initial phase of the laser beam play important roles for the electron to enter and be trapped by the high laser intensity zone.

Taking bare land as the control, this paper studied the effects of different planting modes on the soil permeability of sloping farmlands in purple soil area. For the test six planting modes, the soil permeability was in the order of Eriobotrya japonicaCitrus limonVetiveria zizanioides hedgerows +cornLeucaena leucocephala hedgerows + cornHemerocallis fulvacornbare land, and decreased with increasing depth. The eigenvalues of soil infiltration were in the order of initial infiltration rateaverage infiltration ratestable infiltration rate. The soil permeability had significant positive linear correlations with soil total porosity, non-capillary porosity, initial moisture content, water holding capacity, and organic matter content, and significant negative linear correlation with soil bulk density. The common empirical infiltration model could well fit the soil moisture infiltration processes under the six planting modes, while the Kostiakov equation could not.

To evaluate the safety and efficacy of a new intracorporeal pneumatic and ultrasonic lithotriptor (CQS-01) in percutaneous nephrolithotomy (PNL).In the study, 408 patients with renal or upper ureteral stones suitable for PNL treatment were treated with CQS-01 ultrasonic and pneumatic lithotripter. Their stone position: Single side 368 patients and bilaterial 40 patients. Simple kidney stones: 312 patients, combined ureteral and kidney 42 patients, and simple ureteral stones 54 patients. Stone burden: staghorn stone: 95 patients. All the patients were followed up for 1 week post-operation. The data were collected and analyzed with regard to stone burden, postoperative stone clearance rate, operation time, occurrence rate of adverse events.The postoperative stone-free rate was 91.2% and the residual stone rate 8.8%; The mean operation time was (90.5±68.0) min; There were 6 patients (1.5%) who received selective renal artery embolism because of bleeding after operation. One patient had severe urinary infection and no other severe complications happened.CQS-01 ultrasonic and pneumatic lithotriptor is safe and effective in PNL, and suitable for clinical application.

Results from theoretical investigations are presented which show that protons can be accelerated from rest to a few hundred MeV by a 1-PW chirped radially polarized laser pulse of several hundred femtosecond duration and focused to a waist radius comparable to the radiation wavelength. Single-particle calculations are supported by many-particle and particle-in-cell simulations. Compared with laser acceleration by a similar linearly polarized pulse, the gained energies are less, but have better beam quality. For a suitable initial phase, a particle bunch gets accelerated by the axial component Ez of the laser pulse and, initially focused by the transverse electric field component Er. Beam diffraction finally sets in due to the particle-particle Coulomb repulsion, after interaction with the pulse ceases to exist.

To evaluate the safety and efficacy of a new intracorporeal pneumatic and ultrasonic lithotriptor (CQS-01).Eighty-six patients with renal or upper ureteral stones suitable for percutaneous nephrolithotomy (PNL) treatment were randomly divided into trial group (treated with CQS-01 device) and control group (treated with EMS-III device), with 43 patients in either group respectively. All the patients were followed up for 7 ± 3 days post-operation. The data were collected and analyzed with regard to stone burden, postoperative stone clearance rate, operation time, stone fragmentation and extraction time, volume of extracted stones, changes of red blood cells (RBC) and hemoglobin (Hb), occurrence rate of transfusion, changes of blood urea nitrogen (BUN) and creatinine (Cr), serum electrolytes, white blood cells (WBC), as well as body temperature and adverse events rate at 24 hours and 7 ± 3 days post PNL operation.No significant differences were found between the trial group and the control group (P0.05), in terms of patients demography, renal characteristics and stone characteristics. In the trial group and the control group, respectively: the postoperative stone-free rate was 76.74% and 79.07% (P=0.796) and the partial stone clearance rate was 23.26% and 20.93% (P=0.796), the operation time was (92.49 ± 76.59) min and (87.28 ± 50.01) min (P=0.485), the stone fragmentation and extraction time was (50.16 ± 57.11) min and (40.59 ± 31.01) min (P=0.976), the volume of extracted stones was (10.85 ± 20.08) mL and (5.05 ± 6.00) mL (P=0.041). There were also no significant differences in postoperative RBC and Hb drops, occurrence rate of transfusion, post-operative BUN and Cr, body temperature changes, postoperative systemic inflammatory response and adverse events rate at 24 hours and 7 ± 3 days post-operation between the trial and control groups (P0.05).There is no significant difference in clinical safety, efficacy, and the stone clearance capability between CQS-01 device and EMS-III device.

Using numerical simulation, we have studied in detail vacuum electron acceleration induced by an Airy beam. The phase of the field varies slowly, and the intensity of the field is independent of the decaying parameter of the beam in the asymmetric field channel [(AFC) Opt. Express 18, 7300 (2010)] formed by the Airy beam. Results show that an electron entering into the AFC may be captured and gain high energy. Meanwhile, the decaying parameter, injection energy, and injection angle of the electron play important roles in the electron energy gain.

To evaluate the efficacy and morbidity of 24F-tract percutaneous nephrolithotomy (PNL) accessed by two-step dilation.A total of 3052 patients with 3 366 kidneys or upper ureter calculi underwent 24F-tract PNL accessed by two-step dilation between Aug., 2003 and Jan., 2008, including 108 patients with solitary kidney, 68 with kidney cysts, 44 with horseshoe kidney, 26 with vertebral column deformity, 24 with medullary sponge kidney and 1 transplanted kidney. Stone burdens were (47.2+/-35.6) mm in length.99.4% of 3740 operations were successful in one-session access,in which 3348 PNLs were accessed by single tract (89.5%), 366 by double tracts (9.7%) and 26 by triple tracts (0.7%). The mean operating time was (68.4+/-30.9) min, the mean first accessing time were (17.6+/-11.1) min. and the mean calculi-dealing time were (35.0+/-55.3) min. The stone-free rate after one session operation was 100% for single calculus and 72.3% for multiple or staghorn calculi. of all the kidneys, 374 (11.1%) accepted another PNL to remove the residual calculi, and the last stone-free rate of PNL was 88.6%. During and after operation, 52 cases (1.4%) needed transfusion, 12 (0.3%) underwent selective embolization of renal artery and 1 (0.03%) accepted nephrectomy for bleeding control. No injury of organs occurred except for 3 cases with pneumatothorax and 19 (0.5%) with urinary extravazation. No septic shock occurred.24F-tract PNL accessed by two-step dilation wtih ultrasound-guided puncture is effective and safe.

To establish nephrolithiasis rat model induced by nanobacteria and to determine the relationship of nanobacteria with nephrolithiasis.Thirty adult male SD rats were randomized into 3 groups (n=10 each): group A, given an intravenous injection of nanobacteria; group B, given an intravenous injection of nanobacteria and taken tetracycline; group C, as normal control. Eight weeks later, all rats were sacrificed and the kidneys were examined for pathology and the 24-h urine N-acetyl-beta-D-aminoglycoside enzyme (NAG) and lactate dehydrogenase (LDH) were detected.Histopathological studies revealed nanobacteria induced renal tubular crystallization, which was significantly different among the 3 groups (P=0.033). The crystallization was higher in group A than that in group B. The urinary NAG and LDH excretion were significantly different among the 3 groups (P0.001).Nanobacteria may be involved in the pathogenesis of nephrolithiasis. Tetracycline may inhibit stone formation.

To investigate the characteristics of severe renal hemorrhage after percutaneous nephrolithotomy (PNL) and timing of selective transarterial embolization(TAE) .Between May 2005 and March 2010, superselective renal angiography was used to control severe bleeding in 15 of 1418 cases (1520 PNL procedures, 1.06%). In the 15 cases, superselective renal angioembolization was used to control severe bleeding in 13 (0.92%) . The medical records of all the patients who underwent renal angiography and angioembolization were reviewed.Severe bleeding cases after PNL were divided into 3 types according to the clinical characteristics: type I (urgency type), type II (intermittence type) and type III (persistent slow type). There were 3 patients in type I, 6 in type II and 6 in type III. All the patients had a normal coagulation profile before surgery. A total of 11 patients (84.6%) underwent the first-time successful embolization and 2 (15.4%) the second-time successful embolization. The longer time between angioembolization and bleeding was, the more blood loss and transfusion volume were, except for 1 patient in type II . Temporality serum creatinine abnormality was found in 2 patients, one with a solitary kidney patient and the other with angioembolization for both renal bleeding.TAE is a minimally invasive, safe, simple, and highly effective modality for the management of post PNL renal bleeding. This option should be considered early in the management of these cases,especially for Urgency type bleeding.

To detect, culture, and characterize the nanobacteria (NB) from sera of patients with kidney calculi in our department.Blood samples of 24 patients with kidney calculi and of 3 healthy volunteers in our department were collected for NB culture in this study. We used immunohistochemistry, von kossa staining, scanning electron microscopy (SEM), transmission electron microscopy (TEM) to investigate the appearance and components of cultural NB.Twenty-two blood samples out of 24 (91.67%) showed growth of NB, while no NB were detected in volunteers' blood samples. The infection rate of stone group was obviously higher than that of healthy volunteers. After a 4-week culture period, the light microscope revealed coccoid-shaped NB with a diameter of 100-500 nm, which could be identified by immunohistochemistry and von kossa staining. SEM and TEM (negative staining) revealed NB with a hollow interior coated in needle-like apatite crystals. Such nanoparticles could bud-off new ones and therefore appeared like living organisms.NB can be identified from sera of most patients involved in kidney calculi. It may have intimate relation to the formation of kidney calculi because the infection rate of NB blood samples of stone patients was significantly higher than that of healthy volunteers. Immunohistochemistry, von kossa staining, SEM and TEM are special methods for identifying NB from different aspects. The appearance and character are important points to distinguish NB from other nano-sized particles.

Pretreatment of thickened waste activated sludge (TWAS) can facilitate the hydrolysis step of mesophilic anaerobic digestion (MAD) and improves the digestibility. This study examined the effects of microwave/alkali pretreatment on TWAS disintegration and its subsequent batch and semi-continuous MAD. The maximum solubilization ratio of volatile suspended solids, 77%, achieved at 210°C with 0.15 g-NaOH/g-TSS and 10 min holding time. In the biochemical methane potential tests, the vials fed with pretreated TWAS produced 18-46% higher biogas compared to the control. The semi-continuous reacter fed with the pretreated TWAS without neutralization was stable, and the VS reductions and methane yield were 21% and 14% higher than those of the control, respectively.

In order to optimize target temperature, holding time and NaOH dose on solubilization degree of thickened waste activated sludge, a combined NaOH-microwave pretreatment process was studied on the basis of uniform design method. The results indicated that the variables markedly affected the solubilization degree of chemical oxygen demand (COD). The optimal conditions were determined and two-dimensional and tri-dimensional response surfaces were plotted according to the mathematical models. Within the design boundaries, the predicted maximum solubilization ratio of COD (80%) occurred at target temperature of 210°C, holding time of 51min, and NaOH dose of 0.23g-NaOH/g-TSS. Under the optimal conditions, the experimental solubilization ratio of COD (82%) was in agreement with predicted value with 2.5% deviation.

The possibility of enhancing the energy gain in vacuum electron acceleration by Airy beams is examined. The characteristics of transverse acceleration and non-diffraction of Airy beam can lead to the formation of a long “asymmetric field channel” along the propagation axis, where the intense asymmetric field can accelerate the injected electron to higher energy. Meanwhile, the injection energy of electron plays an important role in determining the final energy gain.

To analyze the pathogenic bacterial's distribution and the drug resistance in the upper urinary tract stones, and to provide the information for choosing suitable antibiotics.Stone samples were taken for culture and for drug sensitivity test in 146 patients undergoing percutaneous nephrolithotomy between April 2007 and October 2008, and the results were analyzed.Pathogens presented in 72 (49.3%) patients. There were 70 (86.4%) Gram-negative bacteria strains. Escherichia coli, Pseudomonas aeruginosa and Enterobacter cloacae were the predominant bacteria, accounted for 30.9%(25 strains), 23.5% (19 strains) and 12.3% (10 strains), respectively. There were 10 (12.3%) Gram-positive bacteria strains, the predominant bacteria was Staphylococcus epidermidis (6 strains), accounting for 7.4%. And there was 1 fungi strain (1.2%). Resistance to ampicillin/sulbactam (88.7%), ceftriaxone (81.3%) and ciprofloxacin (67.5%) was most commonly found in pathogen, and the rate of resistance to amikacin, imipenem and piperacillin/tazobactam were 8.6%, 10.0%, 10.0%, respectively. Erythromycylamine, teicoplanin, SMZ-TMP, nitrofurantoin were sensitive to Gram-positive bacteria.Bacterial's distribution of upper urinary tract stones are multiple, and the majority pathogen is Gram-negative bacteria. A big variant resistance is found among different bacterium. The suitable antibiotics should be chosen according to the different bacterium in the patients who underwent percutaneous nephrolithotomy.

To evaluate the correlation between stone culture and SIRS, ascertain the clinical implication of stone culture in PCNL.Clinical data of 66 patients who underwent PCNL in our department were analyzed retrospectively. Eight risk factors including stone culture + drug sensitivity, urine culture + drug sensitivity, age, gender, prophylactic antibiotics, stone volume, operative time and the number of tract. Multiple statistics methods were used for analysis to evaluate the impact of SIRS, and compare the difference between stone culture and urine culture.Univariate analysis and Multivariate logistic regression model showed that positive stone culture was the risk factor of SIRS (P0.05). Positive stone culture was found in 48.48% patients, which was higher than that of urine culture (30.30%). Fourteen patients (66.67%) of 21 postoperative SIRS patients were prescribed antibiotics according to the stone culture result. And all of them recovered unevenly without developing septic shock or MODS.Positive stone culture is the important risk factor of post-PCNL SIRS. Stone culture is better than urine culture in directing postoperative antibiotics prescripsion and should be routinely used.

The recent proposal to use Weinger transformation field (WTF) [Opt. Express 17, 4959-4969 (2009)] for describing tightly focused laser beams is investigated here in detail. In order to validate the accuracy of WTF, we derive the numerical field (NF) from the plane wave spectrum method. WTF is compared with NF and Lax series field (LSF). Results show that LSF is accurate close to the beam axis and divergent far from the beam axis, and WTF is always accurate. Moreover, electron dynamics in a tightly focused intense laser beam are simulated by LSF, WTF and NF, respectively. The results obtained by WTF are shown to be accurate.

To analyze the risk factors for systemic inflammatory response syndrome (SIRS) after percutaneous nephrolithotomy (PCNL) and to quantitatively predict the probability of SIRS after PCNL.Medical records on 209 patients who underwent PCNL were retrospectively analyzed. The chi2 test, the t-test and a logistic regression model were used to identify key risk factors of SIRS after PCNL. A predictive equation was then formulated to assess the risk of SIRS according to the results from the logistic model. Subsequently, the accuracy of the equation by calculating sensitivity, specificity, overall correct percentage, and positive and negative predictive values was tested.The incidence of SIRS after PCNL was 23.4%. The key risk factors for SIRS following PCNL were: the number of tracts, receipt of a blood transfusion, stone size, and presence of pyelocaliectasis. Other factors added no independent risk to the development of SIRS. The calculated values for sensitivity, specificity, overall percentage correct, positive predictive value and negative predictive value were 44.9%, 95.0%, 83.3%, 73.3%, and 84.9%, respectively.Number of tracts, receipt of a blood transfusion, stone size and presence of pyelocaliectasis are identified as the key risk factors for SIRS after PCNL. The predictive equation allows for an individualized and quantitative assessment of the probability of SIRS after PCNL.

To investigate the clinical efficacy and safety of combining pneumatic and ultrasonic power during PCNL.From Sep 2003 to Aug 2005, we treated 486 patients (509 kidneys) by combining pneumatic and ultrasonic power during percutaneous nephrolithotomy. Clinical data were analyzed retrospectively.The percutaneous renal access was successfully established in 478 patients under ultrasound guidance and immediate phase I lithotripsy was performed, and delayed phase II lithotripsy was performed for 6 patients. Average time required for entire procedure is 73 mins, and average time for stone management is 41 mins. No severe complications occurred. No Residual stone fragment in 438 kidneys, stone free rate was 86.1%. Residual stone fragment was found in 71 kidneys by postoperative KUB and received second PCNL or adjuvant ESWL.The combined application of pneumatic and ultrasonic power in PCNL appears to be efficacious and safe for disintegrating and removing renal calculi.

To evaluate the efficacy and safety of management of renal stone in non-dilated collecting system by percutaneous nephrolithotripsy (PCNL) under ultrasound guidance.From September 2003 to April 2005, 132 cases of renal stone in non-dilated collecting system were performed by percutaneous nephrolithotripsy. A stent was first inserted into the pelvis through cystoscope, and saline was instilled to dilate collecting system. Antegrade percutaneous access was obtained by B-type ultrasound guidance. A combination pneumatic and ultrasonic lithotrite were used to disintegrate and remove stone under direct vision. Clinical data including operation time, complications and stone free rate were analyzed retrospectively.The percutaneous renal access was successfully established under B-type ultrasound guidance in all patients, immediate phase I lithotripsy was performed in 129 cases and delayed phase II lithotripsy in 3 cases. Operation time ranged from 70 to 130 minutes, average time was (89 +/- 11) minutes, 3 cases were supported by blood transfusion, severe complications did not occur during nephrolithotripsy. Stones were cleared in 114 out of 132 cases (86.4%) during immediate phase I lithotripsy, residual stone fragment was found in 18 cases who received second PCNL or adjuvant extracorporeal shock wave lithotripsy.The management of renal stone in non-dilated collecting system using PCNL appears to be efficacious and safe under B-type ultrasound guidance.

Electron acceleration in vacuum driven by a tightly focused radially polarized Gaussian beam has been studied in detail. Weniger transformation method is used to eliminate the divergence of the radially polarized electromagnetic field derived from the Lax series approach. And, electron dynamics in an intense radially polarized Gaussian beam is analyzed by using the Weniger transformation field. The roles of the initial phase of the electromagnetic field and the injection angle, position and energy of electron in energy gain of electron have been studied in detail.