Mechanosensitive calcium signaling promotes epithelial tight junction remodeling by activating RhoA

Epithelia maintain an effective barrier by remodeling cell-cell junctions in response to mechanical stimuli. Cells often respond to mechanical stress through activating RhoA and remodeling actomyosin. Previously, we found that local leaks in the barrier are rapidly repaired by localized, transient activation of RhoA – ″Rho flares″ – but how Rho flares are initiated remains unknown. Here, we discovered that intracellular calcium flashes occur in Xenopus laevis epithelial cells undergoing Rho flare-mediated remodeling of tight junctions. Calcium flashes originate at the site of barrier leaks and propagate into the cell. Depletion of intracellular calcium or inhibition of mechanosensitive calcium channels (MSC) reduced the amplitude of calcium flashes and diminished the activation of Rho flares. Furthermore, MSC-dependent calcium influx was necessary to maintain global barrier function by regulating local repair of tight junctions through efficient junction contraction. We propose that MSC-dependent calcium flashes are an important mechanism allowing epithelial cells to sense and respond to local leaks induced by mechanical stimuli.

Strategic Approach to Massive Chylous Leakage after Neck Dissection

(1) Background: A high volume of chylous leakage (>1 L/day) is a potentially lethal complication after neck dissection. However, a strategic treatment for when the leakage progresses from high to massive (>4 L/day) is lacking. (2) Methods: The PubMed database was searched for articles on neck dissection–associated chylous leakage. Nine articles that included 14 cases with >1 L/day chylous leakage (CL) were analyzed. (3) Results: Of the nine patients with 1–4 L/day CL, three were successfully managed with conservative treatment, two with thoracic ductal ligation, three with ductal embolization, and one with local repair with a strap muscle flap. Of the remaining five cases with >4 L/day chylous leakage, three were successfully treated with the pectoralis major myocutaneous flap (PMMF) and one was successfully treated with thoracic ductal ligation and one case died. (4) Conclusions: In this review, when leakage was >4 L/day, the aforementioned interventions were ineffective, but applying the PMMF could rescue the intractable complication. We propose a strategic treatment for high (1–4 L/day) and massive (>4 L/day) chylous leakage.

Local Repair of Parts from Polymer Composite Material with the Use of Portable Hot Bonder Control Systems

The object of research is the repair processes of parts made of polymer composite materials using a local heating element. The goal is the development of technology, the selection of equipment for repair of parts and assemblies from polymer composite materials using a local heating element and a vacuum source outside the production area, as part of the aircraft. In the process of performing the work, an analysis and review of the existing equipment for local repair of parts from polymer composite materials was carried out. Equipment for local repair of own and imported production was tested. Based on the results of testing and market analysis, equipment was selected that meets the requirements of ND for the manufacture of parts from polymer composite materials. A technical process for repairing parts using a local heating element and a device for hot gluing has been developed.

Constructions of (r,t)-LRC Based on Totally Isotropic Subspaces in Symplectic Space Over Finite Fields

Linear code with locality [Formula: see text] and availability [Formula: see text] is that the value at each coordinate [Formula: see text] can be recovered from [Formula: see text] disjoint repairable sets each containing at most [Formula: see text] other coordinates. This property is particularly useful for codes in distributed storage systems because it permits local repair of failed nodes and parallel access of hot data. In this paper, two constructions of [Formula: see text]-locally repairable linear codes based on totally isotropic subspaces in symplectic space [Formula: see text] over finite fields [Formula: see text] are presented. Meanwhile, comparisons are made among the [Formula: see text]-locally repairable codes we construct, the direct product code in Refs. [8], [11] and the codes in Ref. [9] about the information rate [Formula: see text] and relative distance [Formula: see text].

DOMESTIC PROBLEMS OF RESIDENTS OF THE REAR REGIONS OF RUSSIA DURING WORLD WAR II

To create an objective picture of the achievement of Victory over the Axis powers, it is necessary to analyse the numerous everyday problems faced by workers of the rear regions of Russia. Preferring the analysis of certain aspects of everyday life (fi rewood harvesting, industrial goods production, public utilities, urban improvement), the authors briefl y considered the historiography of the problem. They showed that researchers began to pay attention to this question only from the beginning of the 1970s. Based on archival materials and the recollections of eyewitnesses, it is shown that the war sharply aggravated the already poorly developed sphere of life. Centralised market funds, local repair and construction facilities were reduced, and there was a shortage of qualifi ed personnel, fuel, transport, etc. On the other hand, the attention of the local leadership, especially in 1941-1942, was focused primarily on the mobilisation of all forces to repel the enemy. In 1943-1945, after increasing state allocations for social needs and fi nding ways out of the current critical situation, domestic problems eased somewhat. The authors come to the conclusion that not only the physical and psychological state of workers depended on solving everyday problems, but the main thing in war conditions was their desire to work for the sake of Victory. Throughout the war, living conditions remained extremely diffi cult. There were objective and subjective reasons for this. In general, the solution of everyday problems depended on the initiative of the workers themselves, their creativity and resourcefulness.

Repair of Block Masonry Panels with CFRP Sheets

In the 1980s, block masonry started to be widely used for new constructions in Italy’s earthquake prone areas. However, recent seismic events demonstrated that block masonry buildings may need to be repaired after earthquakes due to cracking. Construction defects are the main cause for cracking of block work masonry. Carbon fiber reinforced polymer (CFRP) sheets have been used as a local repair method for non-defective and defective wall panels. An experimental program was formulated to investigate the shear behavior of block masonry walls repaired with CFRP sheets. A total of six wall panels were constructed in the laboratory and tested in shear (in-plane lateral loading). It was found that, although the control (non-defective) wall panels had a high ultimate load capacity, the use of CFRPs reduces the effects of construction defects and restores the lateral load capacity in non-defective walls. Overall, this research suggests that the use of epoxy-bonded CFRP sheets could be used for local repair of cracked wall panels.