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• The translabyrinthine approach (TLA) is used for complex VII/VIII schwannomas removal. • TLA is effective for one-stage resection of VII/VIII schwannomas and facial nerve repair. • TLA avoids repeat surgeries in cases of hearing loss and poor facial nerve function. This retrospective study evaluated the outcomes of patients undergoing one-stage resection of VII/VIII schwannomas and hemihypoglossal-facial neurorrhaphy via the translabyrinthine approach (TLA). The study encompassed ten consecutive patients with unilateral hearing loss (six women, four men, mean age: 49.5 ± 12.1 years) who underwent surgery. The cohort included two patients with vestibular schwannomas (VSs), four with facial nerve schwannomas (FNSs) (two originating from the geniculate ganglion of the facial nerve and two from the cerebellopontine angle), one with VS regrowth, and three with residual VSs. Preoperative facial nerve function, assessed using the House–Brackmann (HB) scale, was Grade V in one and Grade VI in nine patients. The mean preoperative duration of facial paralysis was 7.5 ± 6.9 months. All patients underwent gross total resection. Postoperatively, one patient experienced cerebrospinal fluid leaks, which were successfully managed with lumbar drains and surgical revisions. At follow-up, facial nerve function improved in all patients: HB Grade V to III in one, HB Grade VI to III in one, HB Grade VI to IV in seven, and Grade VI to V in one. No tumor recurrence was observed during the follow-up period (mean duration: 16.6 ± 9.3 months), and no patient had hemilingual atrophy. The TLA for one-stage resection of VII/VIII schwannomas and facial nerve reconstruction is effective in treating both regrowth and residual VSs and FNSs in the cerebellopontine angle or petrosal bone in patients with severe preoperative facial palsy. This technique facilitates simultaneous tumor removal and nerve anastomosis, thereby reducing the need for multiple surgical interventions in patients with hearing loss and compromised facial nerve function. [ABSTRACT FROM AUTHOR]

We investigate rings where every full element is fine. In particular, we show that the endomorphism ring of any vector space has this property, so such rings are as fine as possible. Consequently, we are able to construct new examples of fine rings. [ABSTRACT FROM AUTHOR]

An increasing number of heavy pollution enterprises are enthusiastically involved in green merger and acquisition (GMA), but the impact on green technology innovation (eco-innovation) has yet to be explored. Does it stimulate the quantity or quality of eco-innovation? By manually collecting GMA engagements of China's heavy pollution enterprises from 2010 to 2020, this study employed the staggered DID method to explore this issue. The empirical results show that: (1) GMA significantly improves the quantity rather than the quality of eco-innovation. After a battery of robustness checks, such as the parallel trend test, placebo test, substitution variables, and an adjusted sample interval, the conclusion remains valid. (2) Through analyzing the motivation of GMA, we find that the desire to obtain government green innovation subsidies and enjoy tax preferences prevails, which results in the scale and quality of GMA tending to be smaller and worse, respectively. (3) Moreover, the decline in the quality of environmental disclosure and CSR provides further evidence that the quality of eco-innovation did not improve. Briefly, this study enriches theoretical grounding regarding strategies of GMA in heavy pollution enterprises and provides implications for governments in emerging economies to guide enterprises to sincerely promote both the quantity and quality of eco-innovation via GMA deals. • Green mergers and acquisitions (GMA) stimulate the quantity rather than the quality of green technology innovation. • The real motivation for GMA is to obtain government green innovation subsidies and enjoy more tax preferences. • The scale of GMA tends to be smaller, and the quality of transactions is prone to be worse. • Following GMA, both the quality of environmental information disclosure and CSR exhibit a significant downward trend. [ABSTRACT FROM AUTHOR]

It was proved in [4] that every group ring of a torsion abelian group over a commutative local ring is a semi-clean ring. It was asked in [4] whether every group ring of a torsion abelian group over a commutative clean ring is a semi-clean ring and whether every group ring of a torsion abelian group over a commutative semi-clean ring is a semi-clean ring. In this paper, we give a positive answer to question 1 and a negative answer to question 2. [ABSTRACT FROM AUTHOR]

Facial nerve schwannomas (FNS) are rare benign tumors that can develop in any segment of the facial nerve. Patients often experience facial palsy and hearing loss after FNS removal or even before surgery. 1-3 Double-stage treatment is usually necessary for tumor resection and reconstruction of facial nerve function. 4,5 Video 1 describes the translabyrinthine approach for resection of the middle-posterior cranial fossa dumbbell FNS and end-to-side hypoglossal-facial nerve anastomosis in 1 stage. The case presented is of a 28-year-old female patient who suffered from right-side hearing loss for 1.5 years, right facial paralysis for 2 months (House-Brackmann grade V), and a right middle-posterior fossa dumbbell FNS extending from the right cerebellopontine angle area and internal auditory canal. Gross total resection of the tumor and hypoglossal-facial nerve end-to-side anastomosis were performed during the same procedure. Postoperative facial nerve function was House-Brackmann grade III at the 6-month follow-up. The patient experienced no postoperative complications. This case demonstrates the advantages of the translabyrinthine approach for middle-posterior fossa dumbbell FNS. This approach helps in achieving tumor resection and nerve anastomosis in 1 stage by avoiding multiple surgical intervention s for patients with hearing loss and impaired facial nerve function. The patient consented to surgery and the publication of her images. [ABSTRACT FROM AUTHOR]

Abstract: Platelet-derived growth factor-B (PDGF-B) is a growth factor that regulates cell migration, proliferation, and differentiation, and is involved in several physical and pathological processes. The overexpression of PDGF-B in glioma surgical samples revealed its effect on tumorigenesis. In this study, we determined that the expression of PDGF-B in 54 glioma samples varied among different grades and was correlated with the cell proliferation marker, Ki-67. Using pyrosequencing, we quantitatively assessed PDGF-B gene methylation levels and determined that hypomethylation promotes increased expression of PDGF-B in higher grade gliomas. Furthermore, we treated two glioma cell lines with a demethylating agent (5-aza-2׳-deoxycitidine, 5-aza-dC) or a remethylating agent (folate) to alter the methylation status of PDGF-B. The epigenetic regulation of the PDGF-B gene not only modulated the expression levels of PDGF-B but also affected the cellular proliferation induced by TGFβ-Smad activity and the PDGF-B peptide itself. Our work showed the importance of the methylation status of the PDGF-B gene promoter, and suggests that the epigenetic regulation of the PDGF-B gene may serve as a potential therapeutic target for the inhibition of glioma proliferation. [Copyright &y& Elsevier]

Abstract: A well-known result of Wolfson [7] and Zelinsky [8] says that every linear transformation of a vector space V over a division ring D is a sum of two invertible linear transformations except when and . Indeed, many of these linear transformations satisfy a stronger property that they are sums of two commuting invertible linear transformations. The goal of this note is to prove that every linear transformation of a vector space V over a division ring D is a sum of two commuting invertible ones if and only if and . As a consequence, a sufficient and necessary condition is obtained for a semisimple module to have the property that every endomorphism is a sum of two commuting automorphisms. [Copyright &y& Elsevier]

Abstract: This paper concerns the formal matrix ring over a ring R defined by a central element s in R. Various basic properties of these rings are established; the isomorphism problem between these rings is addressed; some known results on the usual matrix rings are extended to the formal matrix rings; and the Cayley–Hamilton Theorem is proved for matrices in a formal matrix ring. [Copyright &y& Elsevier]

Abstract: Let K s(R) be the generalized matrix ring over a ring R with multiplier s. For a general local ring R and a central element s in the Jacobson radical of R, necessary and sufficient conditions are obtained for K s(R) to be a strongly clean ring. For a commutative local ring R and an arbitrary element s in R, criteria are obtained for a single element of K s(R) to be strongly clean and, respectively, for the ring K s(R) to be strongly clean. Specializing to s =1 yields some known results. New families of strongly clean rings are presented. [Copyright &y& Elsevier]

Abstract: A ring is called a left p.p. ring if every principal left ideal is projective. The objective here is to completely determine the left structural matrix rings over a von Neumann regular ring. [Copyright &y& Elsevier]

Abstract: A new characterization of von Neumann regular rings is obtained, in terms of simple 0-multiplication of matrices, and is used to establish the natural connections between von Neumann regular rings and feebly Baer modules and rings. [Copyright &y& Elsevier]

Abstract: Let be a -algebra acting densely on , where is a commutative ring with unity and is a right vector space over a division -algebra . Let be an arbitrary and fixed polynomial over in noncommuting indeterminates with constant term such that for some occurring in the coefficients of . It is proved that a right ideal of is generated by an idempotent of finite rank if and only if the rank of is bounded above by a same natural number for all . In this case, the rank of the idempotent that generates is also explicitly given. The results are then applied to considering the triangularization of and the irreducibility of , where denotes the additive subgroup of generated by the elements for . [Copyright &y& Elsevier]

Abstract: We prove a Wedderburn–Artin type theorem for algebraic prime subalgebras in simple Artinian algebras, giving a generalized version of Yahaghi’s theorem [B.R. Yahaghi, On F-algebras of algebraic matrices over a subfield F of the center of a division ring, Linear Algebra Appl. 418 (2006) 599–613]. We also show that every semiprime left algebraic subring in a semiprime right Goldie ring must be a semiprime Artinian ring. [Copyright &y& Elsevier]

Abstract: A ring R with identity is called strongly clean if every element of R is the sum of an idempotent and a unit that commute with each other. For a commutative local ring R and for an arbitrary integer , the paper deals with the question whether the strongly clean property of , , and follows from the strongly clean property of . This is ‘Yes’ if by a known result. [Copyright &y& Elsevier]

For a semisimple module M over a ring R with R / J ( R ) Boolean, every endomorphism of M is a sum of an idempotent endomorphism and a locally nilpotent endomorphism. As a consequence, it is proved that, for a vector space V over a division ring D , every linear transformation of V is a sum of an idempotent linear transformation and a locally nilpotent linear transformation if and only if D ≅ F 2 . This can be seen as an answer to the “local” version of a question raised by Breaz et al. in [1] on nil-cleanness of the ring of linear transformations of an infinite dimensional vector space. [ABSTRACT FROM AUTHOR]

Abstract: Let D be a division algebra finite-dimensional over its center C, , the matrix algebra over D, and V be a vector space over C. We characterize all n-linear forms on Ω in terms of reduced traces and elementary operators. For , it is proved that a bilinear form vanishes on zero products of xy and yx if and only if there exist linear maps such that for all . As an application, a bilinear form B is completely characterized if whenever satisfy , where ξ is a fixed nonzero element in C. [Copyright &y& Elsevier]

Abstract: A ring is called nil-clean if each of its elements is a sum of an idempotent and a nilpotent. In response to a question of S. Breaz et al. in [1], we prove that the matrix ring over a division ring D is a nil-clean ring if and only if . As consequences, it is shown that the matrix ring over a strongly regular ring R is a nil-clean ring if and only if R is a Boolean ring, and that a semilocal ring R is nil-clean if and only if its Jacobson radical is nil and is a direct product of matrix rings over . [Copyright &y& Elsevier]

Abstract: Let be a -algebra acting densely on , where is a commutative ring with unity and is a right vector space over a division -algebra . Let be a nonzero right ideal of and let be a nonzero polynomial over with constant term 0 such that for some coefficient of . Suppose that is a nonzero derivation. It is proved that if for all and for some positive integer , then either is generated by an idempotent of finite rank or for some of finite rank. In addition, if is multilinear, then can be chosen such that . [Copyright &y& Elsevier]

Hypoxia is common in Glioblastoma (GBM). By regulating the ‘hypoxia signaling cascade’, hypoxia affects several processes including cell proliferation, invasion, and angiogenesis. Some studies have revealed that signal transducer and activator of transcription (STAT), including STAT1, is abnormal under hypoxia in several cancers. Here, we investigated the role of STAT1 under hypoxia in glioma progression. We found that STAT1 was downregulated under a hypoxic condition in U251 and U373. STAT1 overexpression can not only decrease proliferation, migration and invasion in U251 and U373 but also inhibit tube formation of HBMECs. Moreover, overexpression of STAT1 decreased tumor growth and prolonged the overall survival of xenograft mice. We also showed that STAT1 overexpression inhibited the expression of HIF-1α and VEGF-A. Our work suggests that STAT1 plays a pivotal role as a tumor suppressor in glioma under hypoxia, and it could be a potential new therapeutic target in glioma. [ABSTRACT FROM AUTHOR]