The intersection of the spectra of operator completions

AbstractLet A∈B(H), B∈B(K), C∈B(K,H), X∈B(H,K) and MX=ACXB be an operator completion of the partial operator matrix Q=AC?B. In this note, we consider the intersection of the spectra of MX when X runs over B(H,K). Denote by ∑(A,B,C) the set of scalar λ∈C such that either (A−λ,C) or (B∗−λ̄,C∗) is not right invertible. We prove that⋂X∈B(H,K)σ(MX)=∑(A,B,C)ifdimR(C)=∞,∑(A,B,C)∪Δ(A,B,C)ifdimR(C)<∞,where Δ(A,B,C) is the set of scalars λ∈C such that R((A−λ,C))=H, R((B∗−λ̄,C∗))=K, and ind(A−λ)+ind(B−λ)≠0. We also prove that the intersection is empty if and only if (A,C) and (B∗,C∗) are controllable

catena-Poly[[(2-amino-1,3-benzothia­zole-6-carboxyl­ato-κ2 O,O′)(2,2′-bipyridyl-κ2 N,N′)cadmium]-μ-2-amino-1,3-benzothia­zole-6-carboxyl­ato-κ3 N 1:O,O′]

In the title coordination polymer, [Cd(C8H5N2O2S)2(C10H8N2)]n, the CdII ion is coordinated by a bidentate 2,2-bipyridyl ligand, two O,O′-chelating 2-amino-1,3-benzothia­zole-6-carboxyl­ate (ABTC) ligands and one N-bonded ABTC ligand. The resulting CdN3O4 coordination polyhedron approximates to a very distorted penta­gonal bipramid with one O and one N atom in axial positions. One of the ABTC ligands is bridging to an adjacent metal atom, generating an infinite chain propagating in [100]. A three-dimensional network is constructed from N—H⋯O and N—H⋯N hydrogen bonds and aromatic π–π stacking inter­actions [centroid–centroid separations = 3.641 (2) and 3.682 (3) Å]

catena-Poly[lead(II)-bis­(μ-2-amino-1,3-benzothia­zole-6-carboxyl­ato)]

The title complex, [Pb(C8H5N2O2S)2]n, consists of one PbII ion located on a crystallographic twofold axis and two symmetry-related 2-amino-1,3-benzothia­zole-6-carboxyl­ate (ABTC) ligands. The central PbII ion has a (4 + 2) coordination by four O atoms of the two ABTC ligands and two weaker Pb—S bonding inter­actions (Pb—S secondary bonds) from S atoms of other two neighbouring ABTC ligands. These bonds link the metal ions into zigzag chains along the c axis, which, in turn, aggregate through π–π inter­actions [centroid–centroid distance = 3.7436 Å] between ABTC rings and N—H⋯O and N—H⋯N hydrogen bonds

1-Methyl-5-phen­oxy-3-trifluoro­methyl-1H-pyrazole-4-carbaldehyde oxime

In the title compound, C12H10F3N3O2, the dihedral angle between the phenyl and pyrazole rings is 96.6 (3)°. In the crystal, pairs of O—H⋯N hydrogen bonds link the mol­ecules, forming inversion dimers. Weak inter­molecular C—H⋯F hydrogen bonds are also observed

Visual perceptual learning modulates decision network in the human brain: the evidence from psychophysics, modeling, and functional magnetic resonance imaging

Perceptual learning refers to improved perceptual performance after intensive training and was initially suggested to reflect long-term plasticity in early visual cortex. Recent behavioral and neurophysiological evidence further suggested that the plasticity in brain regions related to decision making could also contribute to the observed training effects. However, how perceptual learning modulates the responses of decision-related regions in the human brain remains largely unknown. In the present study, we combined psychophysics and functional magnetic resonance imaging (fMRI), and adopted a model-based approach to investigate this issue. We trained participants on a motion direction discrimination task and fitted their behavioral data using the linear ballistic accumulator model. The results from model fitting showed that behavioral improvement could be well explained by a specific improvement in sensory information accumulation. A critical model parameter, the drift rate of the information accumulation, was correlated with the fMRI responses derived from three spatial independent components: ventral premotor cortex (PMv), supplementary eye field (SEF), and the fronto-parietal network, including intraparietal sulcus (IPS) and frontal eye field (FEF). In this decision network, we found that the behavioral training effects were accompanied by signal enhancement specific to trained direction in PMv and FEF. Further, we also found direction-specific signal reduction in sensory areas (V3A and MT+), as well as the strengthened effective connectivity from V3A to PMv and from IPS to FEF. These findings provide evidence for the learning-induced decision refinement after perceptual learning and the brain regions that are involved in this process

Surgical techniques in radiation induced temporal lobe necrosis in nasopharyngeal carcinoma patients

Background Radiation induced brain injury ranges from acute reversible edema to late, irreversible radiation necrosis. Radiation induced temporal lobe necrosis is associated with permanent neurological deficits and occasionally progresses to death. Objective We present our experience with surgery on radiation induced temporal lobe necrosis (RTLN) in nasopharyngeal carcinoma (NPC) patients with special consideration of clinical presentation, surgical technique, and outcomes. Method This retrospective study includes 12 patients with RTLN treated by the senior author between January 2010 and December 2014. Patients initially sought medical treatment due to headache; other symptoms were hearing loss, visual deterioration, seizure, hemiparesis, vertigo, memory loss and agnosia. A temporal approach through a linear incision was performed for all cases. RTLN was found in one side in 7 patients, and bilaterally in 5. 4 patients underwent resection of necrotic tissue bilaterally and 8 patients on one side. Results No death occurred in this series of cases. There were no post-operative complications, except 1 patient who developed aseptic meningitis. All 12 patients were free from headache. No seizure occurred in patients with preoperative epilepsy. Other symptoms such as hemiparesis and vertigo improved in all patients. Memory loss, agnosia and hearing loss did not change post-operatively in all cases. The follow-up MR images demonstrated no recurrence of necrotic lesions in all 12 patients. Conclusion Neurosurgical intervention through a temporal approach with linear incision is warranted in patients with radiation induced temporal lobe necrosis with significant symptoms and signs of increased intracranial pressure, minimum space occupying effect on imaging, or neurological deterioration despite conservative management

A Novel Paclitaxel Microemulsion Containing a Reduced Amount of Cremophor EL: Pharmacokinetics, Biodistribution, and In Vivo

The purpose of this study was to prepare a novel paclitaxel (PTX) microemulsion containing a reduced amount of Cremophor EL (CrEL) which had similar pharmacokinetics and antitumor efficacy as the commercially available PTX injection, but a significantly reduced allergic effect due to the CrEL. The pharmacokinetics, biodistribution, in vivo antitumor activity and safety of PTX microemulsion was evaluated. The results of pharmacokinetic and distribution properties of PTX in the microemulsion were similar to those of the PTX injection. The antitumor efficacy of the PTX microemulsion in OVCRA-3 and A 549 tumor-bearing animals was similar to that of PTX injection. The PTX microemulsion did not cause haemolysis, erythrocyte agglutination or simulative reaction. The incidence and degree of allergic reactions exhibited by the PTX microemulsion group, with or without premedication, were significantly lower than those in the PTX injection group (P < .01). In conclusion, the PTX microemulsion had similar pharmacokinetics and anti-tumor efficacy to the PTX injection, but a significantly reduced allergic effect due to CrEL, indicating that the PTX microemulsion overcomes the disadvantages of the conventional PTX injection and is one way of avoiding the limitations of current injection product while providing suitable therapeutic efficacy

Improving mobility of silicon metal-oxide-semiconductor devices for quantum dots by high vacuum activation annealing

To improve mobility of fabricated silicon metal-oxide-semiconductor (MOS) quantum devices, forming gas annealing is a common method used to mitigate the effects of disorder at the Si/SiO2 interface. However, the importance of activation annealing is usually ignored. Here, we show that a high vacuum environment for implantation activation is beneficial for improving mobility compared to nitrogen atmosphere. Low-temperature transport measurements of Hall bars show that peak mobility can be improved by a factor of two, reaching 1.5 m^2/(Vs) using high vacuum annealing during implantation activation. Moreover, the charge stability diagram of a single quantum dot is mapped, with no visible disturbance caused by disorder, suggesting possibility of fabricating high-quality quantum dots on commercial wafers. Our results may provide valuable insights into device optimization in silicon-based quantum computing.Comment: 13 pages, 4 figure

Factors associated with recurrence of postoperative meningioma: A clinical study of 138 patients

Background and purpose: As the postoperative recurrence of meningioma can have devastating effects, it is important to identify factors that can be used to predict this type of tumor recurrence.Material and methods: We have performed a retrospective study involving 138 patients who were surgically treated for intracranial meningioma between 2005 and 2010. The patient population consisted of 80 females and 58 males, with an age range of 23 to 77 years old (mean age = 52 years). We measured associations between meningioma recurrence and clinical features (age, sex, extent of resection, histological type), or radiological features (tumor size, location, shape, calcification, bone changes, brain tumor interface, tumor necrosis, and MRI enhancement).Results: We found statistically higher levels of postoperative meningioma recurrence in patients with high Simpson grade resections, high histological types, tumor diameters &gt; 5 cm, tumors located in the base of the skull or the parasagittal sinus, tumors with unclear border, irregular enhancements on MRI, edema around the tumor, bleeding and necrosis within the tumor, and irregularly shaped tumors (e.g., lobulated or mushroom-shaped). In addition, calcification, age, sex, bone change, and dural tail sign provided no predictive value.Conclusions: We have shown that histological type, degree of resection, bleeding, necrosis, edema, irregular enhancement, location, shape, size, and margin serve as strong predictors for the postoperative recurrence of meningioma tumors