Arachnoid Cyst Presenting With Sudden Hearing Loss

Arachnoid cysts can occur at different intracranial sites, including the cerebellopontine angle (CPA). They often occur in childhood, in the posterior fossa. They may present with symptoms such as dizziness, tinnitus and hearing loss, or they may be asymptomatic. Presentation with sudden deafness is very rare. We report the unusual presentation of a 67-year-old male with CPA arachnoid cyst and the complaint of sudden-onset deafness. In this case, the cystic lesion at the CPA was found by magnetic resonance imaging of the brain. Pathology after retromastoid suboccipital craniotomy confirmed an arachnoid cyst. The treatment of this patient is discussed and the possible causes of CPA arachnoid cyst are briefly reviewed

Block of Tetrodotoxin-resistant Na+ Channel Pore by Multivalent Cations: Gating Modification and Na+ Flow Dependence

Tetrodotoxin-resistant (TTX-R) Na+ channels are much less susceptible to external TTX but more susceptible to external Cd2+ block than tetrodotoxin-sensitive (TTX-S) Na+ channels. Both TTX and Cd2+ seem to block the channel near the “DEKA” ring, which is probably part of a multi-ion single-file region adjacent to the external pore mouth and is involved in the selectivity filter of the channel. In this study we demonstrate that other multivalent transitional metal ions such as La3+, Zn2+, Ni2+, Co2+, and Mn2+ also block the TTX-R channels in dorsal root ganglion neurons. Just like Cd2+, the blocking effect has little intrinsic voltage dependence, but is profoundly influenced by Na+ flow. The apparent dissociation constants of the blocking ions are always significantly smaller in inward Na+ currents than those in outward Na+ current, signaling exit of the blocker along with the Na+ flow and a high internal energy barrier for “permeation” of these multivalent blocking ions through the pore. Most interestingly, the activation and especially the inactivation kinetics are slowed by the blocking ions. Moreover, the gating changes induced by the same concentration of a blocking ion are evidently different in different directions of Na+ current flow, but can always be correlated with the extent of pore block. Further quantitative analyses indicate that the apparent slowing of channel activation is chiefly ascribable to Na+ flow–dependent unblocking of the bound La3+ from the open Na+ channel, whereas channel inactivation cannot happen with any discernible speed in the La3+-blocked channel. Thus, the selectivity filter of Na+ channel is probably contiguous to a single-file multi-ion region at the external pore mouth, a region itself being nonselective in terms of significant binding of different multivalent cations. This region is “open” to the external solution even if the channel is “closed” (“deactivated”), but undergoes imperative conformational changes during the gating (especially the inactivation) process of the channel

Water Volume and Salinity Forecasts of the Small Aral Sea for the Years 2025

The Aral Sea is a saline endorheic basin in Central Asia. From 1960 onwards the lake started to shrink because of the utilization of rivers water for irrigation purposes. Since the irrigation began, massive amounts water has been used. Therefore, the lake divided into two parts in 1987: the Small Aral Sea in the north and the Large Aral Sea in the south. In the Small Aral Sea, the average water salinity increased from 25-130 g/l from 1987 to 2011. From 1999-2011, the water volume of the Small Aral Sea increased from 12.6 to 22.0 km3. Holt's linear trend forecast method was used to predict the water volume and salinity of the Small Aral Sea from 2010 to 2025. The prediction results indicate that the water volume of the Small Aral Sea will increase to around 22.8 km3, and salinity of the Small Aral Sea will rise to approximately 190 g/l by 2025

(Quantum) complexity of testing signed graph clusterability

This study examines clusterability testing for a signed graph in the bounded-degree model. Our contributions are two-fold. First, we provide a quantum algorithm with query complexity $\tilde{O}(N^{1/3})$ for testing clusterability, which yields a polynomial speedup over the best classical clusterability tester known [arXiv:2102.07587]. Second, we prove an $\tilde{\Omega}(\sqrt{N})$ classical query lower bound for testing clusterability, which nearly matches the upper bound from [arXiv:2102.07587]. This settles the classical query complexity of clusterability testing, and it shows that our quantum algorithm has an advantage over any classical algorithm

Description of local dilatancy and local rotation of granular assemblies by microstretch modeling

AbstractThis study investigates the microstretch continuum modeling of granular assemblies while accounting for both the dilatant and rotational degrees of freedom of a macroelement. By introducing the solid volume fraction and the gyration radius of a granular system, the balance equations of the microstretch continuum are transformed into a new formulation of evolution equations comprising six variables: the solid volume fraction, the gyration radius, the velocity field, the averaged angular velocity, the rate of gyration radius, and the internal energy. The bulk microinertia density, the averaged angular velocity, and the microgyration tensor at a macroscopic point are obtained in terms of discrete physical quantities. The bulk part and the rotational part of the microgyration tensor are proposed as the two indices to measure the local dilatancy and local rotation of granular assemblies. It is demonstrated in the numerical simulation that the two indices can be used to identify the shear band evolution in a granular system under a biaxial compression

Low Polarization Voltage and High Sensitivity CMOS Condenser Microphone Using Stress Relaxation Design

AbstractIn this paper, a CMOS condenser microphone with high sensitivity and low polarization voltage was designed, simulated and fabricated. Due to CMOS process temperature variant and lattice defects, the poly-membrane would be invoked normal stress and gradient stress. These two residual stresses would deform the membrane and increase the membrane's rigidity. For these concerns, an interlace slots design is utilized to reduce the normal stress up to 90%, and the annealing process is applied to decrease the gradient stress. The acoustical sensitivity was increased considerably to -45dBV at 2.7V bias voltage, and, the noise level is -85dBV at 1KHz

Tissue-engineered constructs for urethral regeneration

AbstractThose who have urethral injury, long-distance urethral stricture, hypospadias, or epispadias need tissue for urethral repair. Tissue engineering is one of the solutions for urethroplasty. Three components essential for tissue engineering are cells, scaffolds, and bioactive factors. Several animal studies of tissue-engineered urethras have been conducted and progressed to human clinical trials by 1999. These studies have shown that the maximum distance for normal tissue regeneration in tubularized urethral replacement with unseeded matrices is 0.5cm. Although autologous tissue-engineered tabularized urethras have been successful in clinical trials, this method could be an alternative treatment for urethral reconstruction

The Antecedents and Consequences of Word of Mouth: A Meta-Analysis

Abstract. Word of Mouth (WOM) has been an important issue in Marketing research. This paper adopted Meta-analysis method to make quantitative review for the antecedents and consequences of WOM. The results facilitate scholarship in this academic area by clarify the cause-effect linkages when researching on WOM. Theoretical and practical implications were discussed.Keywords. Word of mouth, Meta-analysis, Cause-effect clarification.JEL. M10, L33, L52

Boosting Factual Consistency and High Coverage in Unsupervised Abstractive Summarization

Abstractive summarization has gained attention because of the positive performance of large-scale, pretrained language models. However, models may generate a summary that contains information different from the original document. This phenomenon is particularly critical under the abstractive methods and is known as factual inconsistency. This study proposes an unsupervised abstractive method for improving factual consistency and coverage by adopting reinforcement learning. The proposed framework includes (1) a novel design to maintain factual consistency with an automatic question-answering process between the generated summary and original document, and (2) a novel method of ranking keywords based on word dependency, where keywords are used to examine the coverage of the key information preserved in the summary. The experimental results show that the proposed method outperforms the reinforcement learning baseline on both the evaluations for factual consistency and coverage