Einstein Finsler Metrics and Killing Vector Fields on Riemannian Manifolds

In this paper, we use a Killing form on a Riemannian manifold to construct a class of Finsler metrics. We find equations that characterize Einstein metrics among this class. In particular, we construct a family of Einstein metrics on $S^3$ with ${\rm Ric} = 2 F^2$, ${\rm Ric}=0$ and ${\rm Ric}=- 2 F^2$, respectively. This family of metrics provide an important class of Finsler metrics in dimension three, whose Ricci curvature is a constant, but the flag curvature is not

Instance by Instance: An Iterative Framework for Multi-instance 3D Registration

Multi-instance registration is a challenging problem in computer vision and robotics, where multiple instances of an object need to be registered in a standard coordinate system. In this work, we propose the first iterative framework called instance-by-instance (IBI) for multi-instance 3D registration (MI-3DReg). It successively registers all instances in a given scenario, starting from the easiest and progressing to more challenging ones. Throughout the iterative process, outliers are eliminated continuously, leading to an increasing inlier rate for the remaining and more challenging instances. Under the IBI framework, we further propose a sparse-to-dense-correspondence-based multi-instance registration method (IBI-S2DC) to achieve robust MI-3DReg. Experiments on the synthetic and real datasets have demonstrated the effectiveness of IBI and suggested the new state-of-the-art performance of IBI-S2DC, e.g., our MHF1 is 12.02%/12.35% higher than the existing state-of-the-art method ECC on the synthetic/real datasets.Comment: 14 pages, 12 figures, 10 table

Current Progress in CAR-T Cell Therapy for Solid Tumors

Cancer immunotherapy by chimeric antigen receptor-modified T (CAR-T) cells has shown exhilarative clinical efficacy for hematological malignancies. Recently two CAR-T cell based therapeutics, Kymriah (Tisagenlecleucel) and Yescarta (Axicabtagene ciloleucel) approved by US FDA (US Food and Drug Administration) are now used for treatment of B cell acute lymphoblastic leukemia (B-ALL) and diffuse large B-cell lymphoma (DLBCL) respectively in the US. Despite the progresses made in treating hematological malignancies, challenges still remain for use of CAR-T cell therapy to treat solid tumors. In this landscape, most studies have primarily focused on improving CAR-T cells and overcoming the unfavorable effects of tumor microenvironment on solid tumors. To further understand the current status and trend for developing CAR-T cell based therapies for various solid tumors, this review emphasizes on CAR-T techniques, current obstacles, and strategies for application, as well as necessary companion diagnostics for treatment of solid tumors with CAR-T cells

Clinical study on high-risk factors for contralateral lymph node metastasis in unilateral papillary thyroid carcinoma

Background and purpose: The occurrence of lymph node metastasis in papillary thyroid cancer (PTC) can have adverse effects on the prognosis of patients. This study aimed to investigate risk factors related to the occurrence of contralateral central lymph node metastases (CLNM) and contralateral lateral lymph node metastases (LLNM) when imaging suspected ipsilateral LLNM in unilateral PTC. Methods: We retrospectively analyzed the clinical data of 526 patients who received surgical treatment in the same treatment group of Jiangsu Cancer Hospital Head and Neck Surgery Department from January 2011 to December 2021. They were initially treated with total thyroidectomy and bilateral central lymph node dissection (CLND) ± lateral lymph node dissection, and their postoperative pathology was uni-PTC. This study analyzed the relevant high-risk factors of contralateral lymph node metastasis. Results: Among the 526 patients, 295 had CLNM, including 272 ipsilateral CLNM, 129 contralateral CLNM and 106 of both sides CLNM; 165 patients had LLNM including 129 ipsilateral LLNM, 18 contralateral LLNM, and 18 of both ipsilateral and contralateral LLNM. Contralateral CLNM occurred in 65 (17.8%) of 365 patients who underwent preventive CLND, and contralateral CLNM was found in 68 (42.2%) of 161 patients with therapeutic CLND. Univariate and multivariate regression analyses showed that contralateral CLNM was associated with maximum diameter of tumor ≥2 cm, multiple foci, no Hashimoto's thyroiditis, tumor invasion, number of CLNM≥6 and age <55 years (P<0.05). Maximum diameter of tumor ≥2 cm was related to contralateral LLNM (P<0.05), while lymph extracapsular extension and lymph node metastasis at tumor side were independent risk factors for contralateral CLNM and contralateral LLNM (P<0.05). Follow-up showed that 5-year overall survival (OS) rate was 97.9% and 5-year disease-free survival (DFS) rate was 97.5%. Conclusion: Contralateral CLNM is more likely to occur in patients with maximum diameter of tumor ≥2 cm, multiple foci, no Hashimoto's thyroiditis, number of CLNM ≥6, age <55 years, tumor and lymph extracapsular extension and lymph node metastasis at the cancer side. In clinical practice, bilateral CLND should be considered for patients with high-risk factors to reduce the residual recurrence of the tumor. Since metastatic rate of contralateral LLNM is relatively low, preventive contralateral lateral lymph node dissection should not be performed routinely when there are no high-risk factors mentioned above

Multifrequency Wireless Channel Measurements and Characterization in Large Indoor Office Environments

This article performs extensive channel measurements and characteristics analysis to investigate large-scale fading (LSF) and small-scale fading (SSF) of wireless local area network (WLAN) channels in large indoor office environments. Multifrequency single-input-single-output (SISO) channel measurements are conducted at 3, 5.5, and 6.5 GHz under the same conditions to explore the frequency dependence of LSF, delay spread (DS), and $K$ -factor (KF). Then, SISO channel measurements with different half-power beamwidths (HPBWs) of antennas are performed at 5.5 GHz in access point (AP) to user equipment (UE) and AP-to-AP scenarios. The effects of antenna HPBW on LSF, DS, and KF are investigated, thereby inspiring the AP deployment in high-density (HD) scenarios. Finally, $32 \times 64$ multiple-input-multiple-output (MIMO) channel measurements at 5.5 GHz are conducted to study the SSF of the time nonstationarity and multilink correlation. The time nonstationarity, including the parameters' drifting and cluster evolution caused by the movement of the UE, is verified by the measurement results. Multilink correlations are illustrated from the perspectives of the angular power spectral density (APSD) and correlation matrix collinearity (CMC). The results show that the distance between users and separation angle can affect the multilink correlation.</p