Novel perfluorocarbon-based oxygenation therapy alleviates Post-SAH hypoxic brain injury by inhibiting HIF-1α.

In comparison to other stroke types, subarachnoid hemorrhage (SAH) is characterized by an early age of onset and often results in poor prognosis. The inadequate blood flow at the site of the lesion leads to localized oxygen deprivation, increased level of hypoxia-inducible factor-1α (HIF-1α), and triggers inflammatory responses and oxidative stress, ultimately causing hypoxic brain damage. Despite the potential benefits of oxygen (O2) administration, there is currently a lack of efficient focal site O2 delivery following SAH. Conventional clinical O2 supply methods, such as transnasal oxygenation and hyperbaric oxygen therapy, do not show the ideal therapeutic effect in severe SAH patients. The perfluorocarbon oxygen carrier (PFOC) demonstrates efficacy in transporting O2 and responding to elevated levels of CO2 at the lesion site. Through cellular experiments, we determined that PFOC oxygenation serves as an effective therapeutic approach in inhibiting hypoxia. Furthermore, our animal experiments showed that PFOC oxygenation outperforms O2 breathing, leading to microglia phenotypic switching and the suppression of inflammatory response via the inhibition of HIF-1α. Therefore, as a new type of O2 therapy after SAH, PFOC oxygenation can effectively reduce hypoxic brain injury and improve neurological function.

Theoretical Exploration of Flexible Transmitter Model.

Neural network models generally involve two important components, i.e., network architecture and neuron model. Although there are abundant studies about network architectures, only a few neuron models have been developed, such as the MP neuron model developed in 1943 and the spiking neuron model developed in the 1950s. Recently, a new bio-plausible neuron model, flexible transmitter (FT) model (Zhang and Zhou, 2021), has been proposed. It exhibits promising behaviors, particularly on temporal-spatial signals, even when simply embedded into the common feedforward network architecture. This article attempts to understand the properties of the FT network (FTNet) theoretically. Under mild assumptions, we show that: 1) FTNet is a universal approximator; 2) the approximation complexity of FTNet can be exponentially smaller than those of commonly used real-valued neural networks with feedforward/recurrent architectures and is of the same order in the worst case; and 3) any local minimum of FTNet is the global minimum, implying that it is possible to identify global minima by local search algorithms.

Biphoton generation enhanced by nonlocal nonlinearity via Rydberg interactions.

Strongly correlated Stokes and anti-Stokes photon pairs (biphotons) exhibiting very large generation rates and spectral brightnesses could be attained at extremely low pump powers and optical depths. This is realized via spontaneous four-wave mixing in cold atoms with enhanced nonlocal (Rydberg) optical nonlinearities and prepared into a dark state with a large population imbalance. The scheme works with all light fields on resonance yet with negligible linear absorption and Raman gain.

Tough and antibacterial poly(l-lactic acid) composites prepared via blending with the bifunctional macromolecular ionomer.

In order to expand the application of PLLA in the packaging field, improving its toughness and antibacterial activity has been widely concerned. However, seldom researches can simultaneously efficiently improve the toughness and antibacterial activity of PLLA by adding one kind of additions. To address above problems, the bifunctional branched poly(butylene adipate) ionomer additive (b-PBAUi) was synthesized. For b-PBAUi, its branched structure not only increased the plasticizing effect of additive, but also acted as reaction sites to introduce more antibacterial ionic salt. Due to the special structure of b-PBAUi, PLLA/b-PBAUi blends achieved excellent toughness and antibacterial efficiency. The elongation of blend reached 125 % even by adding 5 wt% b-PBAUi, which was 10 times higher than that of PLLA. From the analysis of phase morphology, it could be found that the microvoids promoting tensile yielding was the main tensile toughening mechanism for PLLA/b-PBAUi blends. In addition, the antibacterial activity of PLLA was significantly improved by adding b-PBAUi. For PLLA/b-PBAUi10 and PLLA/b-PBAUi15, the antibacterial efficiency against E. coli and S. aureus bacteria exceeded 99.0 %. By comprehensive consideration, the optimal blend ratio was achieved by PLLA/b-PBAUi10 due to its excellent toughness and antibacterial efficiency.

Effect of China's long-term care insurance on health outcomes of older disabled people: role of institutional care.

Since the public long-term care insurance (LTCI) system was piloted in Chengdu, China, in October 2017, there has been considerable growth of LTC institutions in China. This study aimed to evaluate the health value effect of LTCI in older patients with severe disabilities in an LTC institution. This prospective study was based on data from 985 severe disability patients with or without LTCI from October 2017 to May 2021 in the Eighth People's Hospital, Chengdu, China. The Cox proportional hazard model estimated LTCI's health value, including survival probability and risk of pneumonia/pressure ulcers. Subgroup analysis was performed for sex, age, Charlson Comorbidity Index (CCI), and the number of drugs. In the analysis, 519 and 466 patients in LTCI and non-LTCI groups were included, respectively. In adjusted Cox analyses, the LTCI group had a significantly elevated survival rate compared with the non-LTCI groups at 12 months (P < .001, hazard ratio (HR) = 1.758, 95% confidence interval (CI) 1.300-2.376). At 40 months, the adjusted survival rate was 62.6% in the LTCI group, which was significantly higher (53.7%; P = .003, HR = 1.438, 95% CI 1.131-1.831). The subgroups of patients aged 60 to 79 years (interaction P = .007) and with CCI ≥ 3 (interaction P = .026) were more significantly associated with survival improvement than those aged >80 years and with CCI< 3. The LTCI group was also at lower risk for hospital-acquired pneumonia (P = .016, HR 0.622, 95% CI 0.422-0.917) and pressure ulcers (P = .008, HR 0.695, 95% CI 0.376-0.862). The improved survival of LTCI remained stable in sensitivity analyses. For older patients with severe disabilities, in a LTC institution, LTCI significantly improved their health profile and longevity after a year, suggesting the large role and development potentiality of institution care in the LTCI system of China.

Tailored diffractions of asymmetric columns and symmetric rows in two-dimensional multi-element phase gratings.

Two-dimensional multi-element phase gratings can be engineered to show an even symmetry along one direction while an odd symmetry along the other direction in terms of offset refractive indices in each unit cell. The interplay of such even and odd symmetries has been explored to tailor diffraction columns and rows on demand by making offset refractive indices to satisfy specific requirements and hence attain different types of destructive interference. The resultant tailoring effects include the directional column elimination, the grouped column elimination, and the directional column selection as well as the natural row absence, the grouped row elimination, and the central row selection.

Light transfer transitions beyond higher-order exceptional points in parity-time and anti-parity-time symmetric waveguide arrays.

We propose two non-Hermitian arrays consisting of N = 2l + 1 waveguides and exhibiting parity-time (P T) or anti-P T symmetry for investigating light transfer dynamics based on Nth-order exceptional points (EPs). The P T-symmetric array supports two Nth-order EPs separating an unbroken and a broken phase with real and imaginary eignvalues, respectively. Light transfer dynamics in this array exhibits radically different behaviors, i.e. a unidirectional oscillation behavior in the unbroken phase, an edge-towards localization behavior in the broken phase, and a center-towards localization behavior just at Nth-order EPs. The anti-P T-symmetric array supports also two Nth-order EPs separating an unbroken and a broken phase, which refer however to imaginary and real eigenvalues, respectively. Accordingly, light transfer dynamics in this array exhibits a center-towards localization behavior in the unbroken phase and an origin-centered oscillation behavior in the broken phase. These nontrivial light transfer behaviors and their controlled transitions are not viable for otherwise split lower-order EPs and depend on the underlying SU(2) symmetry of spin-l matrices.

Giant Atoms in a Synthetic Frequency Dimension.

Giant atoms that interact with real-space waveguides at multiple spatial points have attracted extensive attention due to their unique interference effects. Here we propose a feasible scheme for constructing giant atoms in a synthetic frequency dimension with, e.g., a dynamically modulated superconducting resonator and a tailored three-level artificial atom. Both analytical and numerical calculations show good agreement between our scheme and real-space two-level giant atoms. In particular, the symmetry of the model in momentum space can be broken by tuning the phase of the external field applied on the atom, enabling chiral interactions between the atom and the frequency lattice. We further demonstrate the possibility of simulating cascaded interaction and directional excitation transfer in the frequency dimension by directly extending our model to involve more such effective giant atoms.

Topological edge states controlled by next-nearest-neighbor coupling and Peierls phase in a P T-symmetric trimerized lattice.

We study the topological features in a trimerized lattice of parity-time symmetry with comparable nearest-neighbor (NN) and next-nearest-neighbor (NNN) couplings as well as a Peierls phase. Eigen energies of four edge states in two bandgaps, of topological origin verified by the quantized total Zak phase, are surprisingly independent of the NNN coupling and the Peierls phase. Topological regions with respect to the intercell NN coupling, as the intracell NN coupling is fixed, can be extended with reinforced localization strengths for one pair of edge states but reduced with weakened localization strengths for the other pair of edge states, by increasing the NNN coupling. The partial overlapping between extended and reduced topological regions promises then a two-step phase transition of 'zero - two - four' edge states, viable to be periodically modulated by the Peierls phase.

Controlled unidirectional reflection in cold atoms via the spatial Kramers-Kronig relation.

It is known that the Kramers-Kronig (KK) relation between real and imaginary parts of the optical susceptibility in the frequency domain can also be realized in the space domain, as first proposed in [Nat. Photonics9(7), 436 (2015)10.1038/nphoton.2015.106]. We here study a mechanism to implement spatial KK relations in a cold atomic sample and use it to control unidirectional reflectionless for probe light incident from either the left or right side of the sample at will. In our model, the complex frequency dependent atomic susceptibility is mapped into a spatially dependent one, employing a far-detuned driving field of intensity linearly varied in space. The reflection of an incident light from one side of the sample can then be set to vanish over a specific frequency band directly by changing the driving field parameters, such as its intensity and frequency. Also, by incorporating the Bragg scattering into the spatial KK relation, the reflectivity from the opposite side of the sample, though typically small for realistic atomic densities, can be made to increase to improve the reflectivity contrast. The present scheme bears potentials for all-optical network applications that require controllable unidirectional light propagation.

In-phase and anti-phase entanglement dynamics of Rydberg atomic pairs.

We study the correlated evolutions of two far-spaced Rydberg atomic pairs with different resonant frequencies, interacting via van der Waals (vdW) potentials and driven by a common laser field. They are found to exhibit in-phase (anti-phase) beating dynamics characterized by identical (complementary) intra-pair entanglements under a specific condition in regard of inter-pair vdW potentials and driving field detunings. This occurs when each atomic pair just oscillates between its ground state and symmetric entangled state because its doubly excited state and asymmetric entangled state are forbidden due to rigid dipole blockade and perfect destructive interference, respectively. More importantly, optimal inter-pair overall entanglement can be attained at each beating node corresponding to semi-optimal intra-pair entanglements, and inevitable dissipation processes just result in a slow decay of intra-pair and inter-pair entanglements yet without destroying in-phase and anti-phase beating dynamics.

Efficient generation of heralded narrowband color-entangled states.

We show that narrowband two-color entangled single Stokes photons can be generated in a ultra-cold atoms sample via selective excitation of two spontaneous four-wave mixing (SFWM) processes. Under certain circumstances, the generation, heralded by the respective common anti-Stokes photon, is robust against losses and phase-mismatching and is remarkably efficient owing to balanced resonant enhancement of the two four-wave mixing processes in a regime of combined induced transparency. Maximally color-entangled states can be easily attained by adjusting the detunings of the external couplings and driving fields, even when these are quite weak.

Nonreciprocal interference and coherent photon routing in a three-port optomechanical system.

We study the interference between different weak signals in a three-port optomechanical system, which is achieved by coupling three cavity modes to the same mechanical mode. If one cavity serves as a control port and is perturbed continuously by a control signal, nonreciprocal interference can be observed when another signal is injected upon different target ports. In particular, we exhibit frequency-independent perfect blockade induced by the completely destructive interference over the full frequency domain. Moreover, coherent photon routing can be realized by perturbing all ports simultaneously, with which the synthetic signal only outputs from the desired port. We also reveal that the routing scheme can be extended to more-port optomechanical systems. The results in this paper may have potential applications for controlling light transport and quantum information processing.

Effect of intraocular anti-VEGF on cystoid macular edema associated with Henoch-Schonlein purpura-a case report.

BACKGROUND: To report a bilateral cystoid macular edema associated with Henoch-Schonleinpurpura. CASE PRESENTATION: A 21-year-old man presented a bilateral, painless, and bilateral blurred vision for 5 weeks with visual acuity (VA) of 6/12 on the right eye and 6/48 on the left. FA and OCT showed bilateral cystoid macular edema, and the fundus photograph showed retinal hemorrhages. Using intravenous dexamethasone could reduce macular edema, but it reoccurred shortly after switching to oral prednisone. Repeated intraocular injection of anti-VEGF in both eyes was performed and VA improved to 6/6 on the right eye and 6/7.5 on the left with the regression of edema after 6 months follow-up. CONCLUSIONS: Intraocular anti-VEGF might be an alternative choice to glucocorticoid in cases of bilateral cystoid macular edema associated with Henoch-Schonlein purpura.

Controllable unidirectional transport and light trapping using a one-dimensional lattice with non-Hermitian coupling.

We propose a one-dimensional tight-binding lattice with special non-Hermitian coupling, the imaginary part of which is modulated by an effective Peierls phase arising from the synthetic magnetic field. Such a non-Hermitian lattice supports robust unidirectional transport that is reflectionless and immune to defects; it thus can serve as a frequency-selectable light filter. To achieve more applications, we further construct two well-designed structures involving this lattice, namely a heterostructure and a sandwich structure. An optical diode can be realized using the heterostructure, while tunable light trapping and reversal can be realized through phase modulations on the sandwich structure. The results in this paper may not only open up a new path for unconventional light transport but also have potential applications for optical communication.

Controllable optical response in a three-mode optomechanical system by driving the cavities on different sidebands.

We study the controllable optical response in a three-mode optomechanical system comprised of two indirectly coupled cavity modes and an intermediate mechanical mode. The two cavity modes are assumed to have different frequencies and driven by two control fields on the red and blue sidebands, respectively. When the system is perturbed by two probe fields satisfying the specific matching condition, a series of intriguing phenomena can be observed by adjusting phases and amplitudes of the control fields, such as absorption-amplification switching, ultra-narrow response windows, frequency-independent perfect reflection, and ultralong optical group delay. We also compare our system with conventional optomechanical systems to highlight its distinct features. Our results may have potential applications in optical communication and quantum information processing.

Entanglement optimization of filtered output fields in cavity optomechanics.

Output entanglement is a key element in quantum information processing. Here, we show how to obtain optimal entanglement between two filtered output fields in a three-mode optomechanical system. First, we obtain the key analytical expression of optimal time delay between the two filtered output fields, from which we can obtain the optimal coupling for output entanglement without time delay. In this case, our linearized analysis predicts that the entanglement saturates to an optimal value as the optomechanical coupling is increased. Furthermore, we obtain the optimal output entanglement with time delay. These results should be very helpful in conceiving new optomechanical schemes of quantum information processing with their efficiency depending critically on the degree of output entanglement.

Which Combination Treatment Is Better for Spinal Metastasis: Percutaneous Vertebroplasty With Radiofrequency Ablation, 125I Seed, Zoledronic Acid, or Radiotherapy?

BACKGROUND: Percutaneous vertebroplasty (PVP) can not only alleviate pain but also restore mechanical stability with injection of bone cement, whereas it exhibits a poor effect on antitumor activity. But through combinations with other therapies, it may be possible to achieve the maximum effect in clinical treatment. Thus, this study is designed to assess the clinical efficacy of PVP separately combined with 4 ways for spinal metastasis (SM) treatment. STUDY QUESTION: Which combination treatment is better for spinal metastasis, percutaneous vertebroplasty with radiofrequency ablation, I seed, zoledronic acid or radiotherapy? STUDY DESIGN: A total of 169 patients with SM were retrospectively recruited and randomly assigned to 4 groups to receive 4 different ways separately: 49 patients (group A) received PVP plus I seed, 51 (group B) received PVP plus radiofrequency ablation (RFA), 38 (group C) underwent PVP plus zoledronic acid (ZA), and 31 (group D) underwent PVP plus radiotherapy (RT). MEASURES AND OUTCOMES: All of them underwent routine examinations before operation. Visual analog scale (VAS), World Health Organization (WHO) Pain Relief, and ODI were applied to evaluate pain relief and motor function. RESULTS: PVP plus RT achieved the best efficacy in relieving pains, with the highest WHO Pain Relief (P < 0.05). The PVP plus RFA exhibited lowest ODI, suggesting the best outcome after treatment (P < 0.05). The PVP plus I showed the lowest VAS score, but it was the worst to improve the routine exercise ability and relieve pains from patients. The PVP plus ZA presented higher VAS and ODI (P < 0.05). CONCLUSIONS: PVP combined with I seed exhibited the best clinical efficacy in terms of VAS, PVP combined with RT was the best choice in terms of WHO Pain Relief, and PVP combined with RFA showed the best effect in terms of ODI for the treatment of SM.

Sodium tanshinone IIA sulfonate attenuates cardiac dysfunction and improves survival of rats with cecal ligation and puncture-induced sepsis.

Cardiac dysfunction, a common consequence of sepsis, is the major contribution to morbidity and mortality in patients. Sodium tanshinone IIA sulfonate (STS) is a water-soluble derivative of Tanshinone IIA (TA), a main active component of Salvia miltiorrhiza Bunge, which has been widely used in China for the treatment of cardiovascular and cerebral system diseases. In the present study, the effect of STS on sepsis-induced cardiac dysfunction was investigated and its effect on survival rate of rats with sepsis was also evaluated. STS treatment could significantly decrease the serum levels of C-reactive protein (CRP), procalcitonin (PCT), cardiac troponin I (cTn-I), cardiac troponin T (cTn-T), and brain natriuretic peptide (BNP) in cecal ligation and puncture (CLP)-induced) septic rats and improve left ventricular function, particularly at 48 and 72 h after CLP. As the pathogenesis of septic myocardial dysfunction is attributable to dysregulated systemic inflammatory responses, several key cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-10 (IL-10) and high mobility group protein B1 (HMGB1), were detected to reveal the possible mechanism of attenuation of septic myocardial dysfunction after being treated by STS. Our study showed that STS, especially at a high dose (15 mg·kg-1), could efficiently suppress inflammatory responses in myocardium and reduce myocardial necrosis through markedly reducing production of myocardial TNF-α, IL-6 and HMGB1. STS significantly improved the 18-day survival rate of rats with sepsis from 0% to 30% (P < 0.05). Therefore, STS could suppress inflammatory responses and improve left ventricular function in rats with sepsis, suggesting that it may be developed for the treatment of sepsis.

Optically Tunable Gratings Based on Coherent Population Oscillation.

We theoretically study the optically tunable gratings based on a L-type atomic medium using coherent population oscillations from the angle of reflection and transmission of the probe field. Adopting a standing-wave driving field, the refractive index of the medium as well as the absorption are periodically modified. Consequently, the Bragg scattering causes the effective reflection. We show that different intensities of the control field lead to three types of reflection profile which actually correspond to different absorption/amplification features of the medium. We present a detailed analyses about the influence of amplification on the reflection profile as well. The coherent population oscillation is robust to the dephasing effect, and such induced gratings could have promising applications in nonlinear optics and all-optical information processing.