Generation of Ultrabrilliant Polarized Attosecond Electron Bunches via Dual-Wake Injection.

Laser wakefield acceleration is paving the way for the next generation of electron accelerators, for their own sake and as radiation sources. A controllable dual-wake injection scheme is put forward here to generate an ultrashort triplet electron bunch with high brightness and high polarization, employing a radially polarized laser as a driver. We find that the dual wakes can be driven by both transverse and longitudinal components of the laser field in the quasiblowout regime, sustaining the laser-modulated wakefield which facilitates the subcycle and transversely split injection of the triplet bunch. Polarization of the triplet bunch can be highly preserved due to the laser-assisted collective spin precession and the noncanceled transverse spins. In our three-dimensional particle-in-cell simulations, the triplet electron bunch, with duration about 500 as, six-dimensional brightness exceeding 10^{14} A/m^{2}/0.1% and polarization over 80%, can be generated using a few-terawatt laser. Such an electron bunch could play an essential role in many applications, such as ultrafast imaging, nuclear structure and high-energy physics studies, and the operation of coherent radiation sources.

Generation of High-Density High-Polarization Positrons via Single-Shot Strong Laser-Foil Interaction.

We put forward a novel method for producing ultrarelativistic high-density high-polarization positrons through a single-shot interaction of a strong laser with a tilted solid foil. In our method, the driving laser ionizes the target, and the emitted electrons are accelerated and subsequently generate abundant γ photons via the nonlinear Compton scattering, dominated by the laser. These γ photons then generate polarized positrons via the nonlinear Breit-Wheeler process, dominated by a strong self-generated quasistatic magnetic field B^{S}. We find that placing the foil at an appropriate angle can result in a directional orientation of B^{S}, thereby polarizing positrons. Manipulating the laser polarization direction can control the angle between the γ photon polarization and B^{S}, significantly enhancing the positron polarization degree. Our spin-resolved quantum electrodynamics particle-in-cell simulations demonstrate that employing a laser with a peak intensity of about 10^{23} W/cm^{2} can obtain dense (≳10^{18} cm^{-3}) polarized positrons with an average polarization degree of about 70% and a yield of above 0.1 nC per shot. Moreover, our method is feasible using currently available or upcoming laser facilities and robust with respect to the laser and target parameters. Such high-density high-polarization positrons hold great significance in laboratory astrophysics, high-energy physics, and new physics beyond the standard model.

Manipulation of Giant Multipole Resonances via Vortex γ Photons.

Traditional photonuclear reactions primarily excite giant dipole resonances, making the measurement of isovector giant resonances with higher multipolarities a great challenge. In this Letter, the manipulation of collective excitations of different multipole transitions in even-even nuclei via vortex γ photons is investigated. We develop the calculation method for photonuclear cross sections induced by the vortex γ photon beam using the fully self-consistent random-phase approximation plus particle-vibration coupling (RPA+PVC) model based on Skyrme density functional. We find that the electromagnetic transitions with multipolarity J<|m_{γ}| are forbidden for vortex γ photons due to the angular momentum conservation, with m_{γ} being the projection of total angular momentum of γ photon on its propagation direction. For instance, this allows for probing the isovector giant quadrupole resonance without interference from dipole transitions using vortex γ photons with m_{γ}=2. Furthermore, the electromagnetic transition with J=|m_{γ}|+1 vanishes at a specific polar angle. Therefore, the giant resonances with specific multipolarity can be extracted via vortex γ photons. Moreover, the vortex properties of γ photons can be meticulously diagnosed by measuring the nuclear photon-absorption cross section. Our method opens new avenues for photonuclear excitations, generation of coherent γ photon laser and precise detection of vortex particles, and consequently, has significant impact on nuclear physics, nuclear astrophysics and strong laser physics.

Lindenane-Type Sesquiterpene Dimers Mitigate Lipopolysaccharide-Induced Inflammation by Inhibiting Toll-Like Receptor Signaling.

Toll-like receptors (TLRs) recognize pathogen-associated molecular patterns and trigger an inflammatory response via the myeloid differential factor 88 (MyD88)-dependent and toll-interleukin-1 receptor domain-containing adapter-inducing interferon-ß (TRIF)-dependent pathways. Lindenane type sesquiterpene dimers (LSDs) are characteristic metabolites of plants belonging to the genus Sarcandra (Chloranthaceae). The aim of this study was to evaluate the potential anti-inflammatory effects of the LSDs shizukaol D (1) and sarcandrolide E (2) on lipopolysaccharides (LPS)-stimulated RAW264.7 macrophages in vitro, and explore the underlying mechanisms. Both LSDs neutralized the LPS-induced morphological changes and production of nitric oxide (NO), as determined by CCK-8 assay and Griess assay, respectively. Furthermore, shizukaol D (1) and sarcandrolide E (2) downregulated interferon ß (IFNß), tumor necrosis factor α (TNFα) and interleukin-1ß (IL-1ß) mRNA levels as measured by reverse transcription polymerase chain reaction (RT-PCR), and inhibited the phosphorylation of nuclear factor kappa B p65 (p65), nuclear factor kappa-Bα (IκBα), Jun N-terminal kinase (JNK), extracellular regulated kinase (ERK), mitogen-activated protein kinase p38 (p38), MyD88, IL-1RI-associated protein kinase 1 (IRAK1), and transforming growth factor-ß-activated kinase 1 (TAK1) proteins in the Western blotting assay. In conclusion, LSDs can alleviate the inflammatory response by inhibiting the TLR/MyD88 signalling pathway.

Brilliant circularly polarized γ-ray sources via single-shot laser plasma interaction.

Circularly polarized (CP) γ-ray sources are versatile for broad applications in nuclear physics, high-energy physics, and astrophysics. The laser-plasma based particle accelerators provide accessibility for much higher flux γ-ray sources than conventional approaches, in which, however, the circular polarization properties of the emitted γ-photons are usually neglected. In this Letter, we show that brilliant CP γ-ray beams can be generated via the combination of laser plasma wakefield acceleration and plasma mirror techniques. In a weakly nonlinear Compton scattering scheme with moderate laser intensities, the helicity of the driving laser can be transferred to the emitted γ-photons, and their average polarization degree can reach ∼61% (20%) with a peak brilliance of ≳1021 photons/(s · mm2 · mrad2 · 0.1% BW) around 1 MeV (100 MeV). Moreover, our proposed method is easily feasible and robust with respect to the laser and plasma parameters.

Rhodomollosides A and B, glycosides of methyl everninate from the aerial parts of Rhododendron molle.

Two new glycosides of methyl everninate, rhodomollosides A (1) and B (2), were isolated from the aerial parts of a medicinal plant Rhododendron molle. The structures of 1 and 2 were elucidated on the basis of detailed spectroscopic analyses as well as HPLC analyses for thiazolidine derivatives of their sugar moieties. The sugar moiety of rhodomolloside A (1) was elucidated to be a rare monosaccharide, D-allose, while rhodomolloside B (2) was assigned as a D-glucoside of methyl everninate. Furthermore, they were evaluated for their cytotoxicity against RAW264.7 cells, and for their inhibitory effects with a lipopolysaccharide (LPS)-stimulated murine macrophages RAW 264.7 cells model.

Polarized Ultrashort Brilliant Multi-GeV γ Rays via Single-Shot Laser-Electron Interaction.

Generation of circularly polarized (CP) and linearly polarized (LP) γ rays via the single-shot interaction of an ultraintense laser pulse with a spin-polarized counterpropagating ultrarelativistic electron beam has been investigated in nonlinear Compton scattering in the quantum radiation-dominated regime. For the process simulation, a Monte Carlo method is developed which employs the electron-spin-resolved probabilities for polarized photon emissions. We show efficient ways for the transfer of the electron polarization to the high-energy photon polarization. In particular, multi-GeV CP (LP) γ rays with polarization of up to about 95% can be generated by a longitudinally (transversely) spin-polarized electron beam, with a photon flux meeting the requirements of recent proposals for the vacuum birefringence measurement in ultrastrong laser fields. Such high-energy, high-brilliance, high-polarization γ rays are also beneficial for other applications in high-energy physics, and laboratory astrophysics.

Ultrarelativistic Electron-Beam Polarization in Single-Shot Interaction with an Ultraintense Laser Pulse.

Spin polarization of an ultrarelativistic electron beam head-on colliding with an ultraintense laser pulse is investigated in the quantum radiation-dominated regime. We develop a Monte Carlo method to model electron radiative spin effects in arbitrary electromagnetic fields by employing spin-resolved radiation probabilities in the local constant field approximation. Because of spin-dependent radiation reaction, the applied elliptically polarized laser pulse polarizes the initially unpolarized electron beam and splits it along the propagation direction into two oppositely transversely polarized parts with a splitting angle of about tens of milliradians. Thus, a dense electron beam with above 70% polarization can be generated in tensof femtoseconds with realistic laser pulses. The proposed method demonstrates a way for relativistic electron beam polarization with currently achievable laser facilities.

γ-Ray Beams with Large Orbital Angular Momentum via Nonlinear Compton Scattering with Radiation Reaction.

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.

Single-Shot Carrier-Envelope Phase Determination of Long Superintense Laser Pulses.

The impact of the carrier-envelope phase (CEP) of an intense multicycle laser pulse on the radiation of an electron beam during nonlinear Compton scattering is investigated. We have identified a CEP effect specific to the ultrarelativistic regime. When the electron beam counterpropagates with the laser pulse, pronounced high-energy x-ray double peaks emerge near the backward direction relative to the initial electron motion. This is achieved in the relativistic interaction domain, where both the electron energy is required to be lower than for the electron reflection condition at the laser peak and the stochasticity effects in the photon emission need to be weak. The asymmetry parameter of the double peaks in the angular radiation distribution is shown to serve as a sensitive measure for the CEP of up to 10-cycle long laser pulses and can be applied for the characterization of extremely strong laser pulses in present and near future laser facilities.

Feasibility of electron cyclotron autoresonance acceleration by a short terahertz pulse.

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.

Attosecond Gamma-Ray Pulses via Nonlinear Compton Scattering in the Radiation-Dominated Regime.

The feasibility of the generation of bright ultrashort gamma-ray pulses is demonstrated in the interaction of a relativistic electron bunch with a counterpropagating tightly focused superstrong laser beam in the radiation-dominated regime. 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 the 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. The results are measurable with the laser technology available in the near future.

[Comparison of tubeless-percutaneous nephrolithotomy and ureteroscopic lithotripsy in treatment of upper-ureteral calculi sized ≥ 1.5 cm].

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Robust signatures of quantum radiation reaction in focused ultrashort laser pulses.

Radiation-reaction effects in the interaction of an electron bunch with a superstrong focused ultrashort laser pulse are investigated in the quantum radiation-dominated regime. The angle-resolved Compton scattering spectra are calculated in laser pulses of variable duration using a semiclassical description for the radiation-dominated dynamics and a full quantum treatment for the emitted radiation. In dependence of the laser-pulse duration we find signatures of quantum radiation reaction in the radiation spectra, which are characteristic for the focused laser beam and visible in the qualitative behavior of both the angular spread and the spectral bandwidth of the radiation spectra. The signatures are robust with respect to the variation of the electron and laser-beam parameters in a large range. Qualitatively, they differ fully from those in the classical radiation-reaction regime and are measurable with presently available laser technology.

[Analysis for risk factors of systemic inflammatory response syndrome after one-phase treatment for apyrexic calculous pyonephrosis by percutaneous nephrolithotomy].

OBJECTIVE: To investigate the risk factors of systemic inflammatory response syndrome (SIRS) after one-phase treatment for apyrexic calculous pyonephrosis by percutaneous nephrolithotomy (PCNL). METHODS: 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. RESULTS: 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). CONCLUSION: 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.

[Causes and remediations of retrograde intrarenal surgery failure in renal calculi treatment].

OBJECTIVE: To find the causes of retrograde intrarenal surgery (RIRS) failure in renal calculi treatment and evaluate the efficacy and morbidity of remedial measures. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

[Bacterial culture and drug sensitivity analysis of upper urinary tract calculi complicating with infection].

OBJECTIVE: To investigate the bacteriology and drug sensitivity of upper urinary tract calculi patients, and to provide information for choosing suitable antibiotics. METHODS: 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. RESULTS: 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 (P>0.05). 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 (P>0.05). 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. CONCLUSION: 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 ß-lactamase inhibitors would be an ideal empirical therapeutic choice.

[Diagnosis and treatment of hydrocephalus-accompanied renal calculi complicated with renal tumor: 5 case reports].

OBJECTIVE: To investigate the diagnosis and treatment of renal pelvic tumor combined with renal urinary calculi and hydronephrosis. METHODS: Five patients with renal pelvic tumor who underwent relief of the upper urinary obstruction were reviewed. RESULTS: 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. CONCLUSION: 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.

Jackstone in the renal calyx: A rare case report.

BACKGROUND: Jackstone is a rare entity of calculi in urinary tracts and has the characteristic appearance resembling toy jacks. They are nearly always reported to occur in the urinary bladder, we first report a rare case of jackstone located in the obstructed renal calyx. CASE SUMMARY: We report a 46-year-old man presenting with intermittent, painless gross hematuria and left flank pain. Urinary computed tomography revealed staghorn stones and secondary hydronephrosis. A jackstone with radiating branches was found in one of the dilated renal calyx. Percutaneous nephrolithotomy was performed and endoscopic images were recorded during the operation. Postoperative stone composition analysis revealed it as calcium oxalate monohydrate stones. CONCLUSION: Jackstones can occur in the renal collecting system besides the bladder. The unique appearance and imaging manifestations are the most important factors in the diagnosis of jackstones, and further exploration of the formation mechanism is required.

[Application of a novel intracorporeal combined pneumatic and ultrasonic lithotriptor (CQS-01) in percutaneous nephrolithotomy].

OBJECTIVE: To evaluate the safety and efficacy of a new intracorporeal pneumatic and ultrasonic lithotriptor (CQS-01) in percutaneous nephrolithotomy (PNL). METHODS: 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. RESULTS: 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. CONCLUSION: CQS-01 ultrasonic and pneumatic lithotriptor is safe and effective in PNL, and suitable for clinical application.