Anomalous Josephson current through a topological noncoplanar ferromagnetic trilayer.

We present an anomalous Josephson effect in a TI-based Josephson junction with a ferromagnetic insulator (FI) trilayer which has noncoplanar magnetizations. It is shown that there exist equal fractional spin-singlet and -triplet correlations due to the magnetism-tuning chiral Dirac energy band structure. The consequent anomalous Josephson supercurrent is exhibited, in which a 0-πor similar 0-πstate transition through phase shift is induced only by exchange field strength of the first FI region, while theϕ0supercurrent and the maximum one gradually drop with the increase of exchange field strengths of the second and third FI regions without relative state transitions. With the increase of the FI region length, theϕ0supercurrent and the maximum one are also both decreased, are found, which is different from the situation for increasing the exchange filed strength. In addition, the corresponding free energies are presented and discussed.

[Management strategy of burn and wound care ward during coronavirus disease 2019 pandemic].

The prevention and control of coronavirus disease 2019 (COVID-19) has already entered a key period. The patients treated in the burn and wound care ward are susceptible to viral infection because of disease, age and other factors, so it is very important to manage the burn and wound care ward during the prevention and control of COVID-19 pandemic. In this paper, combining with the key clinical problems of prevention and control in hospital during the epidemic period of COVID-19 infection, medical evidence, and clinical and management experience, the authors formulate prevention and control management strategy of the author's unit in order to provide reference for prevention and control of burn and wound care ward.

Spin-current-mediated rapid magnon localisation and coalescence after ultrafast optical pumping of ferrimagnetic alloys.

Sub-picosecond magnetisation manipulation via femtosecond optical pumping has attracted wide attention ever since its original discovery in 1996. However, the spatial evolution of the magnetisation is not yet well understood, in part due to the difficulty in experimentally probing such rapid dynamics. Here, we find evidence of a universal rapid magnetic order recovery in ferrimagnets with perpendicular magnetic anisotropy via nonlinear magnon processes. We identify magnon localisation and coalescence processes, whereby localised magnetic textures nucleate and subsequently interact and grow in accordance with a power law formalism. A hydrodynamic representation of the numerical simulations indicates that the appearance of noncollinear magnetisation via optical pumping establishes exchange-mediated spin currents with an equivalent 100% spin polarised charge current density of 107 A cm-2. Such large spin currents precipitate rapid recovery of magnetic order after optical pumping. The magnon processes discussed here provide new insights for the stabilization of desired meta-stable states.

Microneedle fractional radiofrequency treatment of facial photoageing as assessed in a split-face model.

BACKGROUND: A new therapeutic device passes radiofrequency energy through microneedles to targeted tissue. Three-dimensional photography may be useful for evaluating the clinical efficacy of microneedle fractional radiofrequency (MFR) used on the appearance of rhytids and to improve facial laxity. AIM: To evaluate the efficacy and safety of MFR in the treatment of facial photoageing. METHODS: In total, participants with facial photoageing were enrolled in the study. All volunteers were randomized to receive split-face treatments with MFR 2 months apart. The participants self-evaluated at baseline, Days 1-7, and Months 1 and 3 after the final treatment. Objective evaluation was provided by a three-dimensional in vivo imaging system. In addition, skin melanin index, erythema index, immediate reactions, healing times and other adverse effects were evaluated. RESULTS: Compared with the untreated side, the treated side of most participants improved, based on clinical assessments at the 1- and 3-month follow-up visits after treatment. Both objective and participative assessments were satisfactory. The participants demonstrated a decrease of roughness parameter (Sa) value at each follow-up visit. Compared with pretreatment value, Sa decreased significantly at Months 1 and 3 on the treated side (P < 0.05). Minimal and reversible adverse effects and rapid healing were recorded. CONCLUSIONS: MFR appears to be an excellent treatment for photodamaged facial skin in Chinese patients.

Magnetic cooling for microkelvin nanoelectronics on a cryofree platform.

We present a parallel network of 16 demagnetization refrigerators mounted on a cryofree dilution refrigerator aimed to cool nanoelectronic devices to sub-millikelvin temperatures. To measure the refrigerator temperature, the thermal motion of electrons in a Ag wire-thermalized by a spot-weld to one of the Cu nuclear refrigerators-is inductively picked-up by a superconducting gradiometer and amplified by a SQUID mounted at 4 K. The noise thermometer as well as other thermometers are used to characterize the performance of the system, finding magnetic field independent heat-leaks of a few nW/mol, cold times of several days below 1 mK, and a lowest temperature of 150 µK of one of the nuclear stages in a final field of 80 mT, close to the intrinsic SQUID noise of about 100 µK. A simple thermal model of the system capturing the nuclear refrigerator, heat leaks, and thermal and Korringa links describes the main features very well, including rather high refrigerator efficiencies typically above 80%.

Elevated mean platelet volume is associated with silent cerebral infarction.

BACKGROUND: The presence of silent cerebral infarction (SCI) increases the risk of transient ischaemia attack, symptomatic stroke, cardiovascular disease and dementia. Mean platelet volume (MPV) is a surrogate marker of activated platelets and is considered a link between inflammation and thrombosis. In addition, MPV is a risk predictor for cardiovascular disease, stroke and overall vascular mortality. AIMS: The purpose of the study was to assess the MPV levels in SCI patients. METHODS: A cross-sectional study was conducted to evaluate the association between MPV and SCI in 2215 subjects (1385 men and 830 women). RESULTS: The participants with SCI had higher MPV levels than those without SCI (10.4 ± 1.3 fL vs. 9.2 ± 1.2 fL; P < 0.001). Moreover, the subjects with a high MPV had a higher prevalence of SCI. Multivariate logistic regression analyses revealed that the odds ratios and 95% confidence intervals for SCI according to MPV quartiles were 1.000, 2.131 (1.319-3.444), 3.015 (1.896-4.794), 7.822 (4.874-12.554) respectively (P < 0.001). CONCLUSION: MPV is a novel index for SCI regardless of classical cardiovascular risk factors.

Possible evidence for helical nuclear spin order in GaAs quantum wires.

We present transport measurements of cleaved edge overgrowth GaAs quantum wires. The conductance of the first mode reaches 2e(2)/h at high temperatures T≳10 K, as expected. As T is lowered, the conductance is gradually reduced to 1e(2)/h, becoming T independent at T≲0.1 K, while the device cools far below 0.1 K. This behavior is seen in several wires, is independent of density, and not altered by moderate magnetic fields B. The conductance reduction by a factor of 2 suggests lifting of the electron spin degeneracy in the absence of B. Our results are consistent with theoretical predictions for helical nuclear magnetism in the Luttinger liquid regime.

Lack of an association between the XRCC1 Arg399Gln polymorphism and gastric cancer based on a meta-analysis.

Association between the XRCC1 Arg399Gln polymorphism and susceptibility to gastric cancer has been investigated; overall, the results have been inconclusive. We made a meta-analysis of 13 case-control studies, including 3278 cases and 6243 controls. Crude odds ratios (OR) with 95% confidence intervals (95%CI) were used to assess this possible association. We found no evidence of a significant association between the XRCC1 Arg399Gln polymorphism and gastric cancer risk (in the additive inheritance model, OR = 0.986, 95%CI = 0.831-1.156, in the dominant inheritance model, OR = 1.044, 95%CI = 0.890-1.224 and in the recessive inheritance model, OR = 0.975, 95%CI = 0.894-1.063). We conclude that the XRCC1 Arg399Gln polymorphism is not a risk factor for developing gastric cancer.

Amitriptyline induces nuclear transcription factor-kappaB-dependent glutamate transporter upregulation in chronic morphine-infused rats.

We previously showed that intrathecal co-administration of amitriptyline with morphine upregulates the expression of the glial glutamate transporters glutamate-aspartate transporter (GLAST) and glutamate transporter-1 (GLT-1) and restores neuronal glutamate transporter excitatory amino acid carrier 1 (EAAC1) expression in chronically morphine-infused rats. The present study examined the role of nuclear transcription factor-kappaB (NF-kappaB) in the regulation of the expression of GLAST, GLT-1, and EAAC1 following long-term amitriptyline/morphine co-infusion. Male Wistar rats were implanted with two intrathecal catheters with or without a microdialysis probe; one of the catheters was used for continuous infusion of saline (control), morphine (15 microg/h), or morphine plus amitriptyline (both 15 microg/h) for 5 days, while the other was used for a single daily intrathecal injection of the NF-kappaB inhibitor Ro106-9920 (10 microl of 10 microM) for 5 days. We found that amitriptyline co-infusion restored the antinociceptive effect of morphine (4.5-fold right-shift in the morphine dose-response curve compared with a 65-fold right-shift in its absence) and this effect was inhibited by Ro106-9920 administration (48-fold right-shift). Moreover, amitriptyline/morphine co-infusion increased IkappaBalpha phosphorylation and the translocation of NF-kappaB p65 from the cytosol to the nucleus. Daily intrathecal injection of Ro106-9920 prevented the amitriptyline/morphine-induced NF-kappaB p65 translocation and reversed the amitriptyline/morphine-induced GLAST and GLT-1 upregulation and inhibited the restoration of EAAC1 expression. The Ro106-9920 injections abolished the inhibitory effect of amitriptyline on the morphine-evoked release of excitatory amino acids into the spinal cerebrospinal fluid (CSF) dialysates. In conclusion, amitriptyline/morphine co-infusion restores the antinociceptive effect of morphine and upregulates GLAST and GLT-1 expression and restores EAAC1 expression to baseline levels, thus reducing excitatory amino acid levels in the spinal CSF dialysates. The mechanism involves activation of the NF-kappaB pathway, but may also involve other pathways.

Protective effect of intrathecal ketorolac in spinal cord ischemia in rats: a microdialysis study.

BACKGROUND: The prevention of ischemic paraplegia after thoracoabdominal aortic surgery is challenging for both anesthesiologists and surgeons. In a previous study, we showed that intrathecal ketorolac pre-treatment protects rats against ischemic spinal cord injury. In the present study, using a microdialysis method, we investigated whether this neuroprotective effect was related to changes in the spinal cord release of nitric oxide (NO) or the excitatory amino acids (EAAs) aspartate and glutamate. METHODS: Rats were randomized to receive either intrathecal saline or ketorolac 60 microg (10 rats per group), 1 h before spinal cord ischemic injury induced by balloon inflation of a 2F Fogarty catheter in the thoracic aorta with maintenance of the proximal arterial blood pressure at 40 mmHg for 11 min, followed by reperfusion. Another 10 animals were used as the sham-operated control group. Ischemic injury was assessed by hind limb motor function. Cerebrospinal fluid dialysates were collected at baseline (before ischemia) and at 1, 2, 3, 4, 6, 12 and 24 h after the start of reperfusion, and were analyzed for EAAs using high-performance liquid chromatography and for NO metabolites using an NO analyzer. RESULTS: The results showed that intrathecal ketorolac attenuated spinal cord ischemic injury. Dialysate concentrations of NO and EAAs were increased after spinal cord ischemia, and this effect was inhibited by intrathecal administration of ketorolac. CONCLUSIONS: The results of this study suggest that the neuroprotective effect of intrathecal ketorolac in spinal cord ischemia in rats may be caused by a decrease in the spinal cord release of NO and EAAs.

Nonlinear bio-photonic crystal effects revealed with multimodal nonlinear microscopy.

Highly optically active nonlinear bio-photonic crystalline and semicrystalline structures in living cells were studied by a novel multimodal nonlinear microscopy. Numerous biological structures, including stacked membranes and aligned protein structures are highly organized on a nanoscale and have been found to exhibit strong optical activities through second-harmonic generation (SHG) interactions, behaving similarly to man-made nonlinear photonic crystals. The microscopic technology used in this study is based on a combination of different imaging modes including SHG, third-harmonic generation, and multiphoton-induced fluorescence. With no energy release during harmonic generation processes, the nonlinear-photonic-crystal-like SHG activity is useful for investigating the dynamics of structure-function relationships at subcellular levels and is ideal for studying living cells, as minimal or no preparation is required.

Multiphoton confocal microscopy using a femtosecond Cr:forsterite laser.

With its output wavelength covering the infrared penetrating window of most biological tissues at 1,200-1,250 nm, the femtosecond Cr:forsterite laser shows high potential to serve as an excellent excitation source for the multiphoton fluorescence microscope. Its high output power, short optical pulse width, high stability, and low dispersion in fibers make it a perfect replacement for the currently widely used Ti:sapphire laser. In this paper, we study the capability of using a femtosecond Cr:forsterite laser in multiphoton scanning microscopy. We have performed the multiphoton excited photoluminescence spectrum measurement on several commonly used bioprobes using the 1,230 nm femtosecond pulses from a Cr:forsterite laser. Efficient fluorescence can be easily observed in these bioprobes through two-photon or three-photon excitation processes. These results will assist in the selection of dichroic beam splitter and band pass filters in a multiphoton microscopic system. We have also performed the autofluorescence spectrum measurement from chlorophylls in live leaves of the plant Arabidopsis thaliana excited by 1,230 nm femtosecond pulses from the Cr:forsterite laser. Bright luminescence from chlorophyll, centered at 673 and 728 nm, respectively, can be easily observed. Taking advantage of the bright two-photon photoluminescence from chlorophyll, we demonstrated the two-photon scanning paradermal and cross-sectional images of palisade mesophyll cells in live leaves of Arabidopsis thaliana.

Recurrent fuzzy neural network control for piezoelectric ceramic linear ultrasonic motor drive.

In this study, a recurrent fuzzy neural network (RFNN) controller is proposed to control a piezoelectric ceramic linear ultrasonic motor (LUSM) drive system to track periodic reference trajectories with robust control performance. First, the structure and operating principle of the LUSM are described in detail. Second, because the dynamic characteristics of the LUSM are nonlinear and the precise dynamic model is difficult to obtain, a RFNN is proposed to control the position of the moving table of the LUSM to achieve high precision position control with robustness. The back propagation algorithm is used to train the RFNN on-line. Moreover, to guarantee the convergence of tracking error for periodic commands tracking, analytical methods based on a discrete-type Lyapunov function are proposed to determine the varied learning rates of the RFNN. Then, the RFNN is implemented in a PC-based computer control system, and the LUSM is driven by a unipolar switching full bridge voltage source inverter using LC resonant technique. Finally, the effectiveness of the RFNN-controlled LUSM drive system is demonstrated by some experimental results. Accurate tracking response and superior dynamic performance can be obtained because of the powerful on-line learning capability of the RFNN controller. Furthermore, the RFNN control system is robust with regard to parameter variations and external disturbances.

Intracavity frequency-doubled femtosecond cr(4+):forsterite laser.

The generation of femtosecond optical pulses centered at ~620 nm directly from an all-solid-state laser oscillator is reported. Red pulses with pulse widths of the order of 170 fs were obtained with 24-mW average power at an 81-MHz repetition rate. They were achieved by intracavity frequency doubling of a mode-locked Cr(4+):forsterite laser with a 1-mm-thick beta-BaB(2)O(4) crystal. The process of laser mode locking was modified by surface coating the doubling crystal.

Simultaneous multiwavelength generation from a mode-locked all-solid-state Cr:forsterite laser.

We demonstrate a multiple-channel, mode-locked, all-solid-state Cr:forsterite laser. By inserting an etalon into the laser cavity, we have generated 12 phase-locked channels with 9-19-ps pulse width near 1230 nm with 280-mW average output power from a single laser oscillator. By tuning the etalon bandwidth we can shorten the pulse width in a specific channel to 1.8 ps.

Multimodal nonlinear spectral microscopy based on a femtosecond Cr:forsterite laser.

We demonstrate a novel multimodal nonlinear spectral microscopy based on a femtosecond Cr:forsterite laser at 1230 nm. By acquiring the whole nonlinear spectrum in the visible and near-NIR region, this novel technique allows a combination of different imaging modalities, including second-harmonic generation, third-harmonic generation, and multiple-photon fluorescence. Combined with the selected excitation wavelength, which is located in the IR transparency window, this microscopic technique can provide high penetration depth with reduced damage and is ideal for studying living cells.

Striatal glutamate release during novelty exposure-induced hyperactivity in olfactory bulbectomized rats.

Striatal glutamate release during novelty exposure-induced hyperactivity was studied by microdialysis in freely-moving olfactory bulbectomized (OBX) rats. After collecting three 10 min basal striatal dialysate samples, the animals were transferred to an open-field apparatus (novelty) and locomotor activity recorded for 60 min. OBX rats showed significantly more locomotor activity (1210+/-270 cm) than sham-operated rats (420+/-70 cm), but only in the first 10 min after exposure to the novel environment. During the same period, striatal glutamate levels increased to 163+/-21% of the basal value in OBX rats, while no changes were seen in the striatum of sham-operated controls. These findings suggest that olfactory bulbectomy results in an increased response of the striatal glutamatergic system to novelty stress, and may consequently cause hyperactivity.

Conformational studies of the (+)-trans, (-)-trans, (+)-cis, and (-)-cis adducts of anti-benzo[a]pyrene diolepoxide to N2-dG in duplex oligonucleotides using polyacrylamide gel electrophoresis and low-temperature fluorescence spectroscopy.

Using polyacrylamide gel electrophoresis (PAGE) and low-temperature, laser-induced fluorescence line narrowing (FLN) and non-line narrowing (NLN) spectroscopic methods, the conformational characteristics of stereochemically defined and site-specific adducts derived from the binding of 7 beta,8 alpha-dihydroxy-9 alpha,10 alpha-epoxy-7,8,9,10- tetrahydrobenzo[a]pyrene (anti-BPDE, a metabolite of the environmental carcinogen benzo[a]pyrene), to DNA were studied. The focus of these studies was on the four stereochemically distinct anti-BPDE modified duplexes 5'-d(CCATCGCTACC).(GGTAGCGATGG), where G denotes the lesion site derived from trans or cis addition of the exocyclic amino group of guanine to the C10 position of either (+) or (-)-anti-BPDE. PAGE experiments under non-denaturing conditions showed that the (+)-trans adduct causes a significantly greater retardation in the electrophoretic mobility than the other three adducts, probably the result of important adduct-induced distortions of the duplex structure. Low-temperature fluorescence studies in frozen aqueous buffer matrices showed that the (+)-trans adduct adopts primarily an external conformation with only minor interactions with the helix, but a smaller fraction (approximately 25%) appears to exists in a partially base-stacked conformation. The (-)-trans adduct exists almost exclusively (approximately 97%) in an external conformation. Both cis adducts were found to be intercalated; strong electron-phonon coupling observed in their FLN spectra provided additional evidence for significant pi-pi stacking interactions between the pyrenyl residues and the bases. FLN spectroscopy is shown to be suitable for distinguishing between trans and cis adducts, but lesions with either (+)- or (-)-trans, or (+)- or (-)-cis stereochemical characteristics showed very similar vibrational patterns.(ABSTRACT TRUNCATED AT 250 WORDS)

Interaction of the UvrABC nuclease system with a DNA duplex containing a single stereoisomer of dG-(+)- or dG-(-)-anti-BPDE.

Oligonucleotides containing site-specifically-modified N2-guanine (+)-trans-, (-)-trans-, (+)-cis-, and (-)-cis-BPDE adducts were ligated into 50-base-pair DNA fragments. These substrates were used in reactions with the Escherichia coli UvrABC nuclease system. The interaction of the UvrA2 and UvrA2B complexes with these four stereoisomers was probed using DNase I footprinting and gel mobility shift assays. DNase I digestion of substrates containing each stereoisomer of BPDE displayed a unique pattern which was consistent with the known structure of these DNA adducts. UvrA and UvrA2B appeared to interact very similarly with all four substrates. Binding of UvrA2 to these substrates produced a 33-bp footprint, and the UvrB--DNA complex resulted in footprint of 24 bp. The UvrABC nuclease system produced bimodal incisions at the eighth phosphate 5' and the fifth, sixth, or seventh phosphate 3' to the modified guanine. The variation of the 3' incision site was linked to the stereochemistry and orientation of the BPDE adduct. For example, the 3' incision of the 50-bp duplex containing (-)-trans-BPDE-N2-guanine was inhibited at the fifth phosphate. UvrABC nuclease incision kinetics revealed a hierarchy of specificity. The intercalative cis isomers were incised more efficiently than the corresponding trans isomers which lie in the minor groove. The (+) enantiomers were incised more efficiently than the (-) form for both cis and trans isomers. These observations reveal that UvrABC nuclease recognition and incision are directly influenced by the conformation of the DNA adduct.

Determination of stereospecificity of benzo[a]pyrene diolepoxide-DNA antisera with site-specifically modified oligonucleotides.

Antisera developed against benzo[a]pyrene diolepoxide (BPDE)-DNA adducts are sensitive tools for detection of DNA adducts in human samples. All antisera currently used for biomonitoring studies were produced against DNA or guanosine modified with racemic anti-BPDE. Using a non-competitive enzyme-linked immunosorbent assay (ELISA), Venkatachalam and Wani (Carcinogenesis, 15, 565-572, 1994) recently tested polyclonal and monoclonal (5D2) antisera for cross-reactivity against oligonucleotides containing (+)-and (-)-trans-anti-BPDE-N2-guanine or N6-adenine adducts and showed different stereospecificity for the two antisera. Because of the importance of antiserum specificity in human biomonitoring studies, we have tested several monoclonal (Mab 5D11 and 5D2) and polyclonal (Pab #29) antisera developed against racemic anti-BPDE-DNA adducts, and Mab 8E11 developed against anti-BPDE-guanosine adducts. Stereoisomeric anti-BPDE-modified oligonucleotide adducts in the sequence 5'-d(CC-AT-CG*CTACC)-3' where G* = anti-BPDE-N2-dG with (+)-trans, (-)-trans, (+)-cis and (-)-cis adduct stereochemistry at the C10 position of anti-BPDE were tested by competitive ELISA. Two structurally related 5-methylchrysene diolepoxide adducts with G* = (+)- and (-)-trans-anti-5-MeCDE-N2-dG in the same oligonucleotide were also tested. While Mab5D2 had the highest affinity for the (-)-trans-anti-BPDE-modified oligomer, Mab 5D11 and 8E11 and Pab #29 recognized the (+)-trans-anti-BPDE-modified oligomer better than the (-)-trans-anti-BPDE modified oligomer. Mab 5D11 and Pab #29 recognized racemic anti-BPDE-modified DNA adducts better than trans-anti-BPDE-modified oligonucleotides; however, Mab 8E11 showed similar sensitivity to racemic anti-BPDE-DNA adducts and (+)- and (-)-trans-anti-BPDE-modified oligomers. All antisera exhibited lower reactivities with both 5-MeCDE modified oligomers. Because of their sensitive detection of (+)-trans-anti-BPDE-dG adducts, the primary adduct produced in vivo, Mab 8E11 and 5D11 and Pab #29 are appropriate for measurement of most adducts formed in humans.