Detection of earth faults in electric power cables by analyzing changes in the short-circuit resistance

Paper presents method of earth faults detection in electric power cables based on measurement and analysis of the short circuit resistance value in transient under mechanical bumps exerted on the faulty cable line during detection procedure. Discussed investigated results and formulates conclusions for use in practice.Предложен метод обнаружения дефектов заземления в электрических силовых кабелях, основанный на измерении и анализе сопротивления короткого замыкания при кратковременных механических ударах (толчках), прикладываемых к дефектному кабелю в процессе испытаний. Обсуждаются полученные результаты и формулируются практические рекомендации.Запропоновано метод виявлення дефектів заземлення в електричних силових кабелях, заснований на вимірюванні та аналізі опору короткого замикання при короткочасних механічних ударах (поштовхах), що прикладаються до дефектного кабелю в процесі випробувань. Обговорюються отримані результати і формулюються практичні рекомендації

Design and analysis of fractional factorial experiments from the viewpoint of computational algebraic statistics

We give an expository review of applications of computational algebraic statistics to design and analysis of fractional factorial experiments based on our recent works. For the purpose of design, the techniques of Gr\"obner bases and indicator functions allow us to treat fractional factorial designs without distinction between regular designs and non-regular designs. For the purpose of analysis of data from fractional factorial designs, the techniques of Markov bases allow us to handle discrete observations. Thus the approach of computational algebraic statistics greatly enlarges the scope of fractional factorial designs.Comment: 16 page

Switching discharge phenomena when use composite materials Сu—Сr under low voltage DC inductive load a small power

Paper presents and discusses investigated results of composite materials Cu—Cr used in electric contacts operating under DC low voltage loads of a small power. Formulates conclusions of possibility of the use of just such material to control the arc to glow transformation for practical use in electric auxiliary switching devices.Предложены результаты исследований композиционных материалов Cu—Cr, используемых в качестве электрических контактов при коммутации в цепях постоянного тока низкого напряжения малой мощности. Сделан вывод о возможности использования именно этого материала для контроля изменения свечения дуги при практическом использовании в электрических вспомогательных коммутационных устройствах.Представлено результати досліджень композиційних матеріалів Cu—Cr, що використовують в якості електричних контактів при комутації в ланцюгах постійного струму низької напруги малої потужності. Зроблено висновок про можливість використання саме цього матеріалу для контролю зміни світіння дуги при практичному використанні в електричних допоміжних комутаційних пристроях

Performance of laminated contact material Cu—Mo in open air AC low voltage contactors

In the paper performance of laminated contact material Cu—Mo when use in open air ac low voltage contactors is presented and discussed. On the basis of the investigated results conclusions on effective application of such material to replace silver based compositions are formulated.Представлены и обсуждаются эксплуатационные качества слоистого контактного материала Cu—Mo, используемого в низковольтных контакторах на открытом воздухе. По результатам исследований сформулированы рекомендации по эффективному применению такого материала взамен серебросодержащего.Представлено і обговорюються експлуатаційні властивості шаруватого контактного матеріалу Cu—Mo, який використовується в низьковольтних контакторах на відкритому повітрі. За результатами досліджень сформульо-вано рекомендації щодо ефективного застосування такого матеріалу замість срібловміщуючого

Prosaposin is a regulator of progranulin levels and oligomerization

Progranulin (GRN) loss-of-function mutations leading to progranulin protein (PGRN) haploinsufficiency are prevalent genetic causes of frontotemporal dementia. Reports also indicated PGRN-mediated neuroprotection in models of Alzheimer’s and Parkinson’s disease; thus, increasing PGRN levels is a promising therapeutic for multiple disorders. To uncover novel PGRN regulators, we linked whole-genome sequence data from 920 individuals with plasma PGRN levels and identified the prosaposin (PSAP) locus as a new locus significantly associated with plasma PGRN levels. Here we show that both PSAP reduction and overexpression lead to significantly elevated extracellular PGRN levels. Intriguingly, PSAP knockdown increases PGRN monomers, whereas PSAP overexpression increases PGRN oligomers, partly through a protein–protein interaction. PSAP-induced changes in PGRN levels and oligomerization replicate in human-derived fibroblasts obtained from a GRN mutation carrier, further supporting PSAP as a potential PGRN-related therapeutic target. Future studies should focus on addressing the relevance and cellular mechanism by which PGRN oligomeric species provide neuroprotection

Networked T Cell Death following Macrophage Infection by Mycobacterium tuberculosis

<div><h3>Background</h3><p>Depletion of T cells following infection by <em>Mycobacterium tuberculosis</em> (Mtb) impairs disease resolution, and interferes with clinical test performance that relies on cell-mediated immunity. A number of mechanisms contribute to this T cell suppression, such as activation-induced death and trafficking of T cells out of the peripheral circulation and into the diseased lungs. The extent to which Mtb infection of human macrophages affects T cell viability however, is not well characterised.</p> <h3>Methodology/Principal Findings</h3><p>We found that lymphopenia (<1.5×10⁹ cells/l) was prevalent among culture-positive tuberculosis patients, and lymphocyte counts significantly improved post-therapy. We previously reported that Mtb-infected human macrophages resulted in death of infected and uninfected bystander macrophages. In the current study, we sought to examine the influence of infected human alveolar macrophages on T cells. We infected primary human alveolar macrophages (the primary host cell for Mtb) or PMA-differentiated THP-1 cells with Mtb H37Ra, then prepared cell-free supernatants. The supernatants of Mtb-infected macrophages caused dose-dependent, caspase-dependent, T cell apoptosis. This toxic effect of infected macrophage secreted factors did not require TNF-α or Fas. The supernatant cytotoxic signal(s) were heat-labile and greater than 50 kDa in molecular size. Although ESAT-6 was toxic to T cells, other Mtb-secreted factors tested did not influence T cell viability; nor did macrophage-free Mtb bacilli or broth from Mtb cultures. Furthermore, supernatants from <em>Mycobacterium bovis</em> Bacille de Calmette et Guerin (BCG)- infected macrophages also elicited T cell death suggesting that ESAT-6 itself, although cytotoxic, was not the principal mediator of T cell death in our system.</p> <h3>Conclusions</h3><p>Mtb-Infected macrophages secrete heat-labile factors that are toxic to T cells, and may contribute to the immunosuppression seen in tuberculosis as well as interfere with microbial eradication in the granuloma.</p> </div

Prion-like domain mutations in hnRNPs cause multisystem proteinopathy and ALS

Summary Algorithms designed to identify canonical yeast prions predict that ~250 human proteins, including several RNA-binding proteins associated with neurodegenerative disease, harbor a distinctive prion-like domain (PrLD) enriched in uncharged polar amino acids and glycine. PrLDs in RNA-binding proteins are essential for the assembly of ribonucleoprotein granules. However, the interplay between human PrLD function and disease is not understood. Here, we define pathogenic mutations in PrLDs of hnRNPA2/B1 and hnRNPA1 in families with inherited degeneration affecting muscle, brain, motor neuron and bone, and a case of familial ALS. Wild-type hnRNPA2 and hnRNPA1 display an intrinsic tendency to assemble into self-seeding fibrils, which is exacerbated by the disease mutations. Indeed, the pathogenic mutations strengthen a ‘steric zipper’ motif in the PrLD, which accelerates formation of self-seeding fibrils that cross-seed polymerization of wild-type hnRNP. Importantly, the disease mutations promote excess incorporation of hnRNPA2 and hnRNPA1 into stress granules and drive the formation of cytoplasmic inclusions in animal models that recapitulate the human pathology. Thus, dysregulated polymerization caused by a potent mutant ‘steric zipper’ motif in a PrLD can initiate degenerative disease. Related proteins with PrLDs must be considered candidates for initiating and perhaps propagating proteinopathies of muscle, brain, motor neuron and bone

Laser spectroscopy for breath analysis : towards clinical implementation

Detection and analysis of volatile compounds in exhaled breath represents an attractive tool for monitoring the metabolic status of a patient and disease diagnosis, since it is non-invasive and fast. Numerous studies have already demonstrated the benefit of breath analysis in clinical settings/applications and encouraged multidisciplinary research to reveal new insights regarding the origins, pathways, and pathophysiological roles of breath components. Many breath analysis methods are currently available to help explore these directions, ranging from mass spectrometry to laser-based spectroscopy and sensor arrays. This review presents an update of the current status of optical methods, using near and mid-infrared sources, for clinical breath gas analysis over the last decade and describes recent technological developments and their applications. The review includes: tunable diode laser absorption spectroscopy, cavity ring-down spectroscopy, integrated cavity output spectroscopy, cavity-enhanced absorption spectroscopy, photoacoustic spectroscopy, quartz-enhanced photoacoustic spectroscopy, and optical frequency comb spectroscopy. A SWOT analysis (strengths, weaknesses, opportunities, and threats) is presented that describes the laser-based techniques within the clinical framework of breath research and their appealing features for clinical use.Peer reviewe

Preservation of microvascular barrier function requires CD31 receptor-induced metabolic reprogramming

Endothelial barrier (EB) breaching is a frequent event during inflammation, and it is followed by the rapid recovery of microvascular integrity. The molecular mechanisms of EB recovery are poorly understood. Triggering of MHC molecules by migrating T-cells is a minimal signal capable of inducing endothelial contraction and transient microvascular leakage. Using this model, we show that EB recovery requires a CD31 receptor-induced, robust glycolytic response sustaining junction re-annealing. Mechanistically, this response involves src-homology phosphatase activation leading to Akt-mediated nuclear exclusion of FoxO1 and concomitant \u3b2-catenin translocation to the nucleus, collectively leading to cMyc transcription. CD31 signals also sustain mitochondrial respiration, however this pathway does not contribute to junction remodeling. We further show that pathologic microvascular leakage in CD31-deficient mice can be corrected by enhancing the glycolytic flux via pharmacological Akt or AMPK activation, thus providing a molecular platform for the therapeutic control of EB response