Multilevel certification system for engineers

Multilevel certification system was proposed, which is based on existing procedures in the world and in Europe. The system covers all the period of possessor’s carrier: from the school till own engineering projects and honorable titles. New levels are included to the system, e.g. for school and university students. Engineering certificates and personal data of applicants should be saved in e-register. This register is built similar to so called labor book for Soviet Union employees.На основі аналізу існуючих процедур атестації інженерів у Європі та світі й власного досвіду запропонована багаторівнева система сертифікації, яка охоплює весь період професійної кар’єри майбутнього апліката: від шкільних технічних гуртків до створення власних інженерних проектів та одержання почесних титулів. До системи включено нові рівні сертифікації, зокрема для школярів і студентів. Інформація щодо персональних досягнень має зберігатися в електронному реєстрі, який вибудуваний подібно до відповідних розділів трудової книжки.На основе анализа существующих процедур аттестации инженеров в Европе и мире была предложена многоуровневая система сертификации, охватывающая весь период профессиональной карьеры будущего соискателя: от школьных технических кружков до реализации собственных инженерных проектов и награждения почетными титулами. В систему включены новые уровни сертификации, в частности, для школьников и студентов. Информация о персональных достижениях должна сохраняться в электронном реестре, который создан по принципам, подобным соответствующим разделам в трудовой книжке

Amplicon metagenomics of dung beetles (Coleoptera, Scarabaeidae, Scarabaeinae) as a proxy for lemur (Primates, Lemuroidea) studies in Madagascar

Dung beetles (Scarabaeidae, Scarabaeinae) are among the most cost-effective and informative biodiversity indicator groups, conveying rich information about the status of habitats and faunas of an area. Yet their use for monitoring the mammal species, that are the main providers of the food for the dung beetles, has only recently been recognized. In the present work, we studied the diet of four endemic Madagascan dung beetles (Helictopleurus fissicollis (Fairmaire), H. giganteus (Harold), Nanos agaboides (Boucomont), and Epilissus splendidus Fairmaire) using high-throughput sequencing and amplicon metagenomics. For all beetle species, the ⅔–¾ of reads belonged to humans, suggesting that human feces are the main source of food for the beetles in the examined areas. The second most abundant were the reads of the cattle (Bos taurus Linnaeus). We also found lower but significant number of reads of six lemur species belonging to three genera. Our sampling localities agree well with the known ranges of these lemur species. The amplicon metagenomics method proved a promising tool for the lemur inventories in Madagascar

Two-enzyme systems for glycolipid and polyglycerolphosphate lipoteichoic acid synthesis in Listeria monocytogenes

Lipoteichoic acid (LTA) is an important cell wall polymer in Gram-positive bacteria and often consists a polyglycerolphosphate backbone chain that is linked to the membrane by a glycolipid. In Listeria monocytogenes this glycolipid is Gal-Glc-DAG or Gal-Ptd-6Glc-DAG. Using a bioinformatics approach, we have identified L. monocytogenes genes predicted to be involved in glycolipid (lmo2555 and lmo2554) and LTA backbone (lmo0644 and lmo0927) synthesis. LTA and glycolipid analysis of wild-type and mutant strains confirmed the function of Lmo2555 and Lmo2554 as glycosyltransferases required for the formation of Glc-DAG and Gal-Glc-DAG. Deletion of a third gene, lmo2553, located in the same operon resulted in the production of LTA with an altered structure. lmo0927 and lmo0644 encode proteins with high similarity to the staphylococcal LTA synthase LtaS, which is responsible for polyglycerolphosphate backbone synthesis. We show that both proteins are involved in LTA synthesis. Our data support a model whereby Lmo0644 acts as an LTA primase LtaP and transfers the initial glycerolphosphate onto the glycolipid anchor, and Lmo0927 functions as LTA synthase LtaS, which extends the glycerolphosphate backbone chain. Inactivation of LtaS leads to severe growth and cell division defects, underscoring the pivotal role of LTA in this Gram-positive pathogen

Location, synthesis and function of glycolipids and polyglycerolphosphate lipoteichoic acid in Gram-positive bacteria of the phylum Firmicutes.

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Role of electrostatic interactions in the retention of pharmaceutically active contaminants by a loose nanofiltration membrane

The role of electrostatic interactions in the separation of pharmaceuticals by a loose nanofiltration (NF) membrane was examined. While retention of the non-ionizable pharmaceutical carbamazepine was relatively independent of the solution chemistry, retention of the ionizable pharmaceuticals, sulfamethoxazole and ibuprofen, was strongly influenced by the solution pH and ionic strength. This finding is consistent with previous results investigating the effects of solution pH and ionic strength on the retention of proteins and organic acids. Pharmaceutical retention increases dramatically as the compound transforms from a neutral to a negatively charged species when the solution pH increases above its pKa value. In contrast, solution ionic strength suppresses the double layer or the Debye screening length and therefore reduces the effectiveness of electrostatic interaction as a major retention mechanism by the loose NF membranes. However, because of the formation of a hydrated layer around the charged functional groups of the pharmaceuticals and the fact that at a sufficiently high ionic strength the Debye length approaches a relatively constant value, this reduction in retention is relatively small. As a result, even at comparatively elevated ionic strengths, retention of the negatively charged sulfamethoxazole and ibuprofen by the loose NF membrane is considerably high

Mode-Selective Control of the Crystal Lattice

Driving phase changes by selective optical excitation of specific vibrational modes in molecular and condensed phase systems has long been a grand goal for laser science. However, phase control has to date primarily been achieved by using coherent light fields generated by femtosecond pulsed lasers at near-infrared or visible wavelengths. This field is now being advanced by progress in generating intense femtosecond pulses in the mid-infrared, which can be tuned into resonance with infrared-active crystal lattice modes of a solid. Selective vibrational excitation is particularly interesting in complex oxides with strong electronic correlations, where even subtle modulations of the crystallographic structure can lead to colossal changes of the electronic and magnetic properties. In this Account, we summarize recent efforts to control the collective phase state in solids through mode-selective lattice excitation. The key aspect of the underlying physics is the nonlinear coupling of the resonantly driven phonon to other (Raman-active) modes due to lattice anharmonicities, theoretically discussed as ionic Raman scattering in the 1970s. Such nonlinear phononic excitation leads to rectification of a directly excited infrared-active mode and to a net displacement of the crystal along the coordinate of all anharmonically coupled modes. We present the theoretical basis and the experimental demonstration of this phenomenon, using femtosecond optical spectroscopy and ultrafast X-ray diffraction at a free electron laser. The observed nonlinear lattice dynamics is shown to drive electronic and magnetic phase transitions in many complex oxides, including insulator–metal transitions, charge/orbital order melting and magnetic switching in manganites. Furthermore, we show that the selective vibrational excitation can drive high-T_C cuprates into a transient structure with enhanced superconductivity. The combination of nonlinear phononics with ultrafast crystallography at X-ray free electron lasers may provide new design rules for the development of materials that exhibit these exotic behaviors also at equilibrium

Accruals Quality and Firm Value

I examine the importance of the properties of accounting information to equity investors by estimating the implicit prices of accruals quality and operating volatility revealed from observed stock prices. I measure accruals quality parameters based on the model in Nikolaev [2016], which separates the volatility of accounting error from the volatility of the performance component of accruals. I use the hedonic regression approach, which relies on rational expectations (Bajari et al. [2012]) to identify the effect of accruals quality on firm value. This approach isolates time-varying unobservable factors correlated with accruals quality. My findings indicate that investors have preferences for higher accruals quality. At the margin, a 1% increase in the volatility of accounting error results in a 0.50% decrease in the firm value. At the same time, my findings indicate that investors have preferences for lower operating risk, which statistically and economically dominates preferences for accruals quality. At the margin, a 1% increase in the operating volatility results in a 1.43% decrease in the firm value. Overall, my findings suggest that the effect of accruals quality on firm value is largely driven by the operating risk. This result is robust to the choice of the model of time-varying unobservable firm characteristics and to different sets of control variables