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This paper presents a novel approach to counterbalance free-carrier-absorption (FCA) in electro-optic (E-O) Mach-Zehnder interferometer (MZI) cells by harnessing self-heating effect. We show insights on crosstalk limitations in MZIs with direct carrier-injection and provide a detailed design methodology on a differential phase shifter pair. Leveraging both free-carrier dispersion (FCD) and self-heating effects, our design enables arbitrary phase tuning with balanced FCA loss in the pair of arms, eliminating the need for additional phase corrections and creating ultralow crosstalk MZI elements. This neat design disengages from the commonly used nested structure and thus provides an opportunity of embedding tunable couplers for correcting imperfect splitting ratios given that only two of which are needed. We show that with the use of tunable direction couplers (DCs), a standard ±10 nm process variation is tolerated, whilst achieving below -40dB crosstalk ratio. By direct carrier injection in both arms, the proposed device operates at nanosecond scales and can bring about a breakthrough in the scalability of E-O switch fabrics, as well as other silicon integrated circuits that have stringent requirements on crosstalk leakage.

In this paper, to the best of our knowledge, we propose the first multi-rate Nyquist-subcarriers modulation (SCM) for C-band 100Gbit/s signal transmission over 50km dispersion-uncompensated link. Chromatic dispersion (CD) introduces severe spectral nulls on optical double-sideband signal, which greatly degrades the performance of intensity-modulation and direct-detection systems. Based on the prior knowledge of the dispersive channel, Nyquist-SCM with multi-rate subcarriers is proposed to keep away from the CD-caused spectral nulls flexibly. Signal on each subcarrier can be individually recovered by a digital signal processing, including the feed-forward equalizer with no more than 31 taps, a two-tap post filter, and maximum likelihood sequence estimation with one memory length. Combining with entropy loading based on probabilistic constellation shaping to maximize the capacity-reach, the C-band 100Gbit/s multi-rate Nyquist-SCM signal over 50km dispersion-uncompensated link can achieve 7% hard-decision forward error correction limit and average normalized generalized mutual information of 0.967 at received optical power of -4dBm and optical signal-to-noise ratio of 47.67dB. In conclusion, the multi-rate Nyquist-SCM shows great potentials in solving the CD-caused spectral distortions., Comment: This paper has been accepted by Journal of Lightwave Techonlogy

We synthesized a PbO2-coated electrode consisting of three layers, with Pb–0.6%Sb alloy as the substrate, α-PbO2 as the intermediate layer, and the outermost β-PbO2-Co3O4@C as the active layer for boosting OER activity.

In this paper, we are concerned with regularity of nonlocal stochastic partial differential equations of parabolic type. By using Campanato estimates and Sobolev embedding theorem, we first show the Hölder continuity (locally in the whole state space \begin{document}$ \mathbb{R}^d $\end{document}) for mild solutions of stochastic nonlocal diffusion equations in the sense that the solutions belong to the space \begin{document}$ C^{\gamma}(D_T;L^p(\Omega)) $\end{document} with the optimal Hölder continuity index \begin{document}$ \gamma $\end{document} (which is given explicitly), where \begin{document}$ D_T: = [0, T]\times D $\end{document} for \begin{document}$ T>0 $\end{document}, and \begin{document}$ D\subset\mathbb{R}^d $\end{document} being a bounded domain. Then, by utilising tail estimates, we are able to obtain the estimates of mild solutions in \begin{document}$ L^p(\Omega;C^{\gamma^*}(D_T)) $\end{document}. What's more, we give an explicit formula between the two indexes \begin{document}$ \gamma $\end{document} and \begin{document}$ \gamma^* $\end{document}. Moreover, we prove Hölder continuity for mild solutions on bounded domains. Finally, we present a new criterion to justify Hölder continuity for the solutions on bounded domains. The novelty of this paper is that our method is suitable to the case of space-time white noise.

α-Fe2O3/Bi2O3 nanocomposites with a p–n heterojunction were synthesized via an anodization strategy and the hydrothermal method for photocatalytic applications.

In this short paper, we focus on the blowup phenomenon of stochastic parabolic equations. We first discuss the probability of the event that the solutions keep positive. Then, the blowup phenomenon in the whole space is considered. The probability of the event that the solutions blow up in finite time is given. Lastly, we obtain the probability of the event that blowup time of stochastic parabolic equations larger than or less than the deterministic case.

In this paper, we consider the existence of multiple periodic solutions for a class of second-order difference equations with quadratic–supquadratic growth condition at infinity. Moreover, we give three examples to illustrate our main result.

In addition to complex preparation and low-yield syntheses, attaining high energy density while maintaining high power density remains a significant challenge for supercapacitor applications in the field of energy storage. Herein, two-dimensional (2D) nickel-based metal-organic framework (NiMOF) nanosheets are grown around carbon nanotubes (CNTs) to form NiMOF/CNTs composite, which is synthesized

This study aimed to examine the efficacy of sulforaphane (SFN) in preventing radiation-induced muscle fibrosis (RIMF) and the potential role in nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated antioxidant stress.The RIMF model was established by a single irradiation of the left thigh of C57BL/6 J mice, and the mice were then randomly divided into control, SFN, irradiation (IR), and IR + SFN (IR/SFN) groups. The serum and skeletal muscle were collected eight weeks after irradiation, and changes in oxidative stress and muscle fibrosis were detected.The IR group showed a more obvious skeletal muscle fiber atrophy, significantly higher number of collagen fibers, and higher inflammatory cell infiltration compared to control group. Compared to the IR group, the IR/SFN group had orderly arranged muscle fibers, decreased collagen fibers, and infiltration of inflammatory cells. In addition, compared with the control group, the expression of oxidative stress-related indexes was significantly increased, accompanied by activation of the transforming growth factor (TGF-β)/Smad pathway and its downstream fibrogenic molecules in the skeletal muscle of the IR group. After SFN intervention, the above indices were significantly restored. Furthermore, SFN induced the upregulation of Nrf2, activation of AKT, and inhibition of GSK-3β and Fyn accumulation.These results revealed that Nrf2 plays a central role in protecting against RIMF. Furthermore, SFN prevents RIMF by activating Nrf2 via the AKT/GSK-3β/Fyn pathway.

Radiotherapy (RT) is an effective treatment for head and neck cancer (HNC). Radiation-induced temporal lobe injury (TLI) is a serious complication of RT. Late symptoms of radiation-induced TLI are irreversible and manifest as memory loss, cognitive impairment, and even temporal lobe necrosis (TLN). It is currently believed that the mechanism of radiation-induced TLI involves microvascular injury, neuron and neural stem cell injury, glial cell damage, inflammation, and the production of free radicals. Significant RT-related structural changes and dose-dependent changes in gray matter (GM) and white matter (WM) volume and morphology were observed through computed tomography (CT) and magnetic resonance imaging (MRI) which were common imaging assessment tools. Diffusion tensor imaging (DTI), dispersion kurtosis imaging (DKI), susceptibility-weighted imaging (SWI), resting-state functional magnetic resonance (rs-fMRI), magnetic resonance spectroscopy (MRS), and positron emission tomography (PET) can be used for early diagnosis and prognosis evaluation according to functional, molecular, and cellular processes of TLI. Early diagnosis of TLI is helpful to reduce the incidence of TLN and its related complications. This review summarizes the clinical features, mechanisms, and imaging of radiation-induced TLI in HNC patients. KEY POINTS: • Radiation-induced temporal lobe injury (TLI) is a clinical complication and its symptoms mainly include memory impairment, headache, and cognitive impairment. • The mechanisms of TLI include microvascular injury, cell injury, and inflammatory and free radical injury. Significant RT-related structural changes and dose-dependent changes in TL volume and morphology were observed through CT and MRI. • SWI, MRS, DTI, and DKI and other imaging examinations can detect anatomical and functional, molecular, and cellular changes of TLI.

Metastatic unresectable malignant melanoma (MM) owing to its intrinsic biological invasion potential and low sensitivity to radiochemotherapy has a poor prognosis and a high rate of mortality; the mean survival period is only 6-8 months, and the 5-year survival rate is less than 10%. The progression of patients with brain and liver metastases is worse than those with other distant or visceral metastases. With the advent of immunotherapy, especially immune-checkpoint inhibitors, long-term remission of stage IV disease may be achieved in some patients. Despite recent advances, not all patients benefit or can afford immunotherapy. Here, we report the case of a 44-year-old man whose initial diagnosis was MM with liver and multiple brain metastases. A high expression of F-box/WD repeat-containing protein 7 (FBXW7) inactivating mutation was observed, and the patient was treated with a combination of everolimus and temozolomide (TMZ) following palliative radiotherapy. The patient was stable for approximately 17 months, and eventually showed an overall survival (OS) of about 19 months. This case is novel and instructional, which highlights that the combination of everolimus and TMZ might be effective, with manageable toxicity, for advanced MM patients with FBXW7 mutation. And it may provide a reference for the treatment of analogous patients.

This work is devoted to examine the uniqueness and existence of kinetic solutions for a class of scalar conservation laws involving a nonlocal super-critical diffusion operator and a multiplicative noise. Our proof for uniqueness is based upon the analysis on double variables method and the existence is enabled by a parabolic approximation., arXiv admin note: substantial text overlap with arXiv:1001.5415, arXiv:1611.00984 by other authors

Intensity modulation and direct detection (IM/DD) with pulse amplitude modulation (PAM) is a cost-effective option for intra- and inter-data center (DC) applications. Due to current demand on DC data traffic, transmission rates beyond 200 Gbit/s/ $\lambda $ are desirable. However, employing commercially available lower bandwidth components introduces severe inter-symbol interference (ISI). In addition, to achieving high-speed data rates, digital signal processing (DSP) schemes like Tomlinson-Harashima precoding (THP) and decision feedback equalizer (DFE) can increase tolerance against ISI. In this letter, we show an experimental comparison of PAM-4, PAM-6 and PAM-8 modulation formats with and without THP on the transmitter-side and Volterra nonlinear equalizer (VNLE) on the receiver-side. We provide also results with and without duobinary (DB) encoding on the transmitter side and DFE on the receiver side. The experiment is conducted using an O-band electro-absorption modulated laser over transmission distances up to 20 km.

We generalize the Kolmogorov continuity theorem and prove the continuity of a class of stochastic fields with the parameter. As an application, we derive the continuity of solutions for nonlocal st...

Intensity modulation and direct detection (IM/DD) together with pulse amplitude modulation (PAM) is a cost-efficient solution for intra-datacenter links. However, sophisticated digital signal processing (DSP) is inevitable to reach the demanded high data rates for these short-reach applications. In this article, we compare different DSP schemes that enable rates of 200 Gb/s/λ and beyond. Those schemes include Tomlinson–Harashima precoding, partial response signaling, Viterbi equalization and post-filtering together with Volterra nonlinear equalization. Extensive experimental measurements are shown in which the DSP approaches are compared at gross rates between 180 Gb/s and 300 Gb/s. The experiments are done in C-band for fiber links of up to 2 km length. As modulation formats, PAM4, PAM6, and PAM8 are considered. Net bit rates well over 200 Gb/s are shown for all formats at a range of 1 km single mode fiber using a transmission system consisting of currently available commercial components. The optimum DSP configuration as well as the best modulation format varies along the investigated data rates. The best solution is shown to change from partial response PAM4 for lower rates to PAM6 and PAM8 at high bit rates.

The rise of timing-critical applications such as virtual reality and connected car fleets, combined with the rapid growth of the number of user devices, creates new challenges for the latency and reliability of user-cloud data communications. Currently user-cloud communications rely on time-scheduled data frames through tree-topology fibre networks, incapable of assuring guaranteed connections with low or stable latency, which is necessary for, e.g. remote surgeries and safe operations of self-driven cars. Besides, their scalability to a larger user count is limited. Here we show that clock and optical frequency synchronisation, enabled by burgeoning frequency comb and signal processing techniques, can provide each user with dedicated optical bandwidth to enable scalable user-cloud communications that guarantee simultaneously high per-user data rate and low latency. Our approach provides accurate clock and optical frequency synchronisation over deployed optical fibre links, which will be beneficial for many applications including accurate navigation, quantum communications, and astronomy.

In this paper, we consider the long time behavior of stochastic evolution equations. The exponential, polynomial and logarithmic decay for stochastic equations are considered. Sufficient conditions are given to obtain these exponents. All the results show the noise (time diffusion) will prevent the solutions to decay in $p$-th moment, which coincides with the fact that the noise is a diffusion process but it will be different in the sense of almost surely, and the partial diffusion operator (spatial diffusion) will accelerate the decay of solutions.

Consider the following stochastic differential equation (SDE): $$ X_{t}=x+ \int _{0}^{t}b(s,X_{s})\,ds+ \int _{0}^{t}\sigma (s,X_{s}) \,dB_{s}, \quad 0\leq t\leq T, x\in \mathbb{R}, $$ X t = x + ∫ 0 t b ( s , X s ) d s + ∫ 0 t σ ( s , X s ) d B s , 0 ≤ t ≤ T , x ∈ R , where $\{B_{s}\}_{0\leq s\leq T}$ { B s } 0 ≤ s ≤ T is a 1-dimensional standard Brownian motion on $[0,T]$ [ 0 , T ] . Suppose that $q\in (1,\infty ]$ q ∈ ( 1 , ∞ ] , $p\in (1,\infty )$ p ∈ ( 1 , ∞ ) , $b=b_{1}+b_{2}$ b = b 1 + b 2 , $b_{1}\in L^{q}(0,T;L^{p}(\mathbb{R}))$ b 1 ∈ L q ( 0 , T ; L p ( R ) ) such that $1/p+2/q 1 / p + 2 / q < 1 and $b_{2}$ b 2 is bounded measurable, with $\sigma \in L^{\infty }(0,T;{\mathcal{C}}_{u}(\mathbb{R}))$ σ ∈ L ∞ ( 0 , T ; C u ( R ) ) there being a real number $\delta >0$ δ > 0 such that $\sigma ^{2}\geq \delta $ σ 2 ≥ δ . Then there exists a weak solution to the above equation. Moreover, (i) if $\sigma \in \mathcal{C}([0,T];\mathcal{C}_{u}(\mathbb{R}))$ σ ∈ C ( [ 0 , T ] ; C u ( R ) ) , all weak solutions have the same probability law on 1-dimensional classical Wiener space on $[0,T]$ [ 0 , T ] and there is a density associated with the above SDE; (ii) if $b_{2}=0$ b 2 = 0 , $p\in [2,\infty )$ p ∈ [ 2 , ∞ ) and $\sigma \in L^{2}(0,T;{\mathcal{C}}_{b}^{1/2}({\mathbb{R}}))$ σ ∈ L 2 ( 0 , T ; C b 1 / 2 ( R ) ) , the pathwise uniqueness holds.

To evaluate the quality of planning target volume (PTV) and organs at risk (OAR) generated by the manual Pinnacle planning (manP) and Auto-Planning (AP) modules and discuss the feasibility of AP in the application of radiotherapy for patients with breast cancer. Thirty patients who underwent breast-conserving therapy were randomly selected. The Philips Pinnacle 9.10 treatment planning system was used to design the manP and AP modules for PTV and OAR distribution on the same computed tomography. A physician compared the plans in terms of dosimetric parameters and monitor units (MUs) using blind qualitative scoring. Statistical differences were evaluated using paired two-sided Wilcoxon’s signed-rank test. On comparing the plans of AP and manP modules, the conformal index (P 50 (P = 0.04) of PTV in the AP group was lower than those in the manP group, while D1 was higher (P = 0.03). In terms of dosimetry of OAR, ipsilateral lung V20 Gy (P 10 Gy (P 5 Gy (P mean (P 40 Gy and Dmean of all patients with breast cancer in the AP group were lower than those in the manP group (P P P = 0.32), although there was no statistical significance. The AP module almost had an equal quality of PTV and dose distribution as the manP module, and its OAR was less irradiated.

Radiation‐induced myocardial fibrosis (RIMF) is a potentially lethal clinical complication of chest radiotherapy (RT) and a final stage of radiation‐induced heart disease (RIHD). RIMF is characterized by decreased ventricular elasticity and distensibility, which can result in decreased ejection fraction, heart failure and even sudden cardiac death. Together, these conditions impair the long‐term health of post‐RT survivors and limit the dose and intensity of RT required to effectively kill tumour cells. Although the exact mechanisms involving in RIMF are unclear, increasing evidence indicates that the occurrence of RIMF is related to various cells, regulatory molecules and cytokines. However, accurately diagnosing and identifying patients who may progress to RIMF has been challenging. Despite the urgent need for an effective treatment, there is currently no medical therapy for RIMF approved for routine clinical application. In this review, we investigated the underlying pathophysiology involved in the initiation and progression of RIMF before outlining potential preventative and therapeutic strategies to counter this toxicity.

The goal of this paper is to establish the Lipschitz and W2,∞ estimates for a second-order parabolic PDE ∂tu(t,x)=12Δu(t,x)+f(t,x) on Rd with zero initial data and f satisfying a Ladyzhenskaya–Prod...

We investigate a stochastic transport equation driven by a multiplicative noise. For drift coefficients in $$L^q(0,T;{\mathcal {C}}^\alpha _b({\mathbb {R}}^d))$$ ( $$\alpha >2/q$$ ) and initial data in $$W^{1,r}({\mathbb {R}}^d)$$ , we show the existence and uniqueness of stochastic strong solutions. Opposite to the deterministic case where the same assumptions on drift coefficients and initial data induce nonexistence of strong solutions, we prove that a multiplicative stochastic perturbation of Brownian type is enough to render the equation well-posed. However, for $$\alpha +1

Radiotherapy (RT) is an effective method for treating head and neck cancer (HNC). However, RT may cause side effects during and after treatment. Radiation-induced brainstem injury (BSI) is often neglected due to its low incidence and short survival time and because it is indistinguishable from intracranial tumor progression. It is currently believed that the possible mechanism of radiation-induced BSI includes increased expression of vascular endothelial growth factor and damage of vascular endothelial cells, neurons, and glial cells as well as an inflammatory response and oxidative stress. At present, it is still difficult to avoid BSI even with several advanced RT techniques. Intensity-modulated radiotherapy (IMRT) is the most commonly used therapeutic technique in the field of RT. Compared with early conformal therapy, it has greatly reduced the injury to normal tissues. Proton beam radiotherapy (PBT) and heavy ion radiotherapy (HIT) have good dose distribution due to the presence of a Bragg peak, which not only results in better control of the tumor but also minimizes the dose to the surrounding normal tissues. There are many clinical studies on BSI caused by IMRT, PBT, and HIT. In this paper, we review the mechanism, dosimetry, and other aspects of BSI caused by IMRT, PBT, and HIT.Key Points• Enhanced MRI imaging can better detect radiation-induced BSI early.• This article summarized the dose constraints of brainstem toxicity in clinical studies using different techniques including IMRT, PBT, and HIT and recommended better dose constraints pattern to clinicians.• The latest pathological mechanism of radiation-induced BSI and the corresponding advanced treatment methods will be discussed.

We obtain new existence of multiple nontrivial M-periodic solutions for a class of second-order discrete Hamiltonian system with the force F(t, x) being neither supquadratic nor subquadratic growth in x. Moreover, we exhibit four instructive examples to illustrate our results.