Band gaps in pseudopotential self-consistent GW calculations

For materials which are incorrectly predicted by density functional theory to be metallic, an iterative procedure must be adopted in order to perform GW calculations. In this paper we test two iterative schemes based on the quasi-particle and pseudopotential approximations for a number of inorganic semiconductors whose electronic structures are well known from experiment. Iterating just the quasi-particle energies yields a systematic, but modest overestimate of the band gaps, confirming conclusions drawn earlier for CaB_6 and YH_3. Iterating the quasi-particle wave functions as well gives rise to an imbalance between the Hartree and Fock potentials and results in bandgaps in far poorer agreement with experiment.Comment: 5 pages, 2 figures, 2 table

Fixed-Point Results on Complete G-Metric Spaces for Mappings Satisfying an Implicit relation of New Type

We prove general fixed-point theorems (generalizing some recent results) in a complete G-metric space.Доведено загальні теореми про нерухому точку у повних G-метричних просторах, що узагальнюють дєякі результати, отримані нещодавно

Obtaining lignin nanoparticles by sonication

Lignin, the main natural aromatic polymer was always aroused researchers interest. Currently around 90% of this biomaterial is burned for energy. It has a very complex and complicated structure which depends on the separation method and plant species, what determine difficulties to use as a raw material widely. This research presents a physical method to modify lignin by ultrasonic irradiation in order to obtain nanoparticles. The nanoparticles synthesized were dimensionally and morphologically characterized. At the same time the preoccupations were to determine the structural and compositional changes that occurred after sonication. To achieve this, two types of commercial lignins (wheat straw and Sarkanda grass) were used and the modifications were analyzed by FTIR-spectroscopy, GPC-chromatography, (31)P-NMR-spectroscopy and HSQC0. The results confirm that the compositional and structural changes of nanoparticles obtained are not significantly modified at the intensity applied but depend on the nature of lignin

Unbiased bases (Hadamards) for 6-level systems: Four ways from Fourier

In quantum mechanics some properties are maximally incompatible, such as the position and momentum of a particle or the vertical and horizontal projections of a 2-level spin. Given any definite state of one property the other property is completely random, or unbiased. For N-level systems, the 6-level ones are the smallest for which a tomographically efficient set of N+1 mutually unbiased bases (MUBs) has not been found. To facilitate the search, we numerically extend the classification of unbiased bases, or Hadamards, by incrementally adjusting relative phases in a standard basis. We consider the non-unitarity caused by small adjustments with a second order Taylor expansion, and choose incremental steps within the 4-dimensional nullspace of the curvature. In this way we prescribe a numerical integration of a 4-parameter set of Hadamards of order 6.Comment: 5 pages, 2 figure

Do Search for Dibaryonic De - Excitations in Relativistic Nuclear Reactions

Some odd characteristics are observed in the single particle distributions obtained from $He + Li$ interactions at $4.5 AGeV/c$ momenta which are explained as the manifestation of a new mechanism of strangeness production via dibaryonic de-excitations. A signature of the formation of hadronic and baryonic clusters is also reported. The di-pionic signals of the dibaryonic orbital de-excitations are analyzed in the frame of the MIT - bag Model and a Monte Carlo simulation.The role played by the dibaryonic resonances in relativistic nuclear collisions could be a significant one. Key words: Relativistic nuclear interactions negative pions, negative kaons, di-pions , streamer chamber, dibaryons, MIT - bag model PACS codes: 25.75.+r,14.40.Aq,14.20.Pt,12.40.AsComment: 17 pages,LATEX, preprint ICTP -243 1993,figures available by reques

Time-space evolution and volcanological features of the Late Miocene-Quaternary Calimani-Gurghiu-Harghita Volcanic Range, East Carpathians, Romania. A Review.

The Carpathian-Pannonian Region (CPR) hosts one of the major Cainozoic volcanic provinces of Europe extending in space over 6 eastern European countries.The lithospheric evolution of this large area governed by large-scale asthenospheric processes is recorded by products of volcanic activity occurred during a time interval of more than 21 million years. According to their surface occurrence areas, ages and composition the Neogene volcanics of CPR were systematized in three main groups: 1) mostly explosive products of felsic magmas generated at the beginning of volcanism in the whole CPR and in their particular occurrence areas (21-12 Ma) developed in the actual intra-Carpathian Pannonian Basin, 2) mostly intermediate calc-alkaline rocks emplaced in both the intra-Carpathian areas and along the arcuate Carpathian fold-and-thrust belt, and 3) Na- and K- alkaline and ultra-alkaline products clustered in a number of monogenetic volcanic fields across the whole intra-Carpathian realm developed in the final stages of volcanic activity of the CPR as a whole and of their particular occurrence areas. The ca. 160 km long Călimani-Gurghiu-Harghita volcanic range (CGH) developed as part of the intermediate calc-alkaline volcanism closely related in space with the fold-and-thrust belt of the Carpathians, representing the south-eastern segment of the CPR. Although its map view and general petrochemical and volcanological characteristics are quite similar with those of other segments of the orogene belt- tied calc-alkaline volcanic segments, at a closer look CGH displays a number of unique features. The time-space evolution of CGH is particular not only in that it is the youngest (10.5 to < 0.05 Ma) dominantly calc-alkaline segment in CPR but also it shows a transient character. Unlike other segments along which volcanism occurred simultaneously forming true subduction-related 400 to 800 km long volcanic fronts which were stable in time for millions of year, in CGH volcanic activity migrated continuously along the range from NW to SE. So, during any given 1 Ma time interval active volcanism was restricted to very limited areas and to just a few active volcanic centers. The along-range shift of volcanic foci was concurrent with progressively lower volumes of magma erupted and decreasing magma output rates. As a result, gradually lower-volume and less complex volcanic edifices were built up. Moreover, at the range-ending and youngest South Harghita sub-segment, magma compositions gradually changed from normal calc-alkaline to high-K calc-alkaline and shoshonitic, and adakitic features emerged at the end of volcanic activity, after a time gap of 0.5 Ma. This marks a major geodynamic event in the development of the East Carpathians themselves. During the transient volcanism of CGH, edifices of varying volume and complexity were built up forming a row of tightly- packed adjoining stratovolcanoes/composite volcanoes whose peripheral volcaniclastic aprons complexly juxtaposed, overlapped and merged with each other. The largest ones (Călimani caldera, and Fâncel-Lăpuşna) developed until caldera stage. Some of them (Rusca-Tihu in the Călimani Mts., Vârghiş in the North Harghita Mts.) became unstable during their growth and collapsed, generating widespread large-volume debris avalanche deposits. Edifice instability was solved by volcano-basement interaction processes, such as volcano spreading, at some large-volume volcanoes (in particular those in the Gurghiu Mts.). Volcano typology changed at the smaller-volume constructs toward the southeastern terminus of the range in the South Harghita Mts. from typical large stratovolcanoes to smaller composite volcanoes, dome clusters and isolated domes and simpler internal structures. As a whole, CGH displays an extremely particular evolutionary pattern strongly suggesting a transient character and decreasing to extinguishing volcanic activity along its length from NW to SE

Nanostructuring induced enhancement of radiation hardness in GaN epilayers

The radiation hardness of as-grown and electrochemically nanostructured GaN epilayers against heavy ion irradiation was studied by means of photoluminescence(PL) and resonant Raman scattering (RRS) spectroscopy. A nanostructuring induced enhancement of the GaN radiation hardness by more than one order of magnitude was derived from the PL and RRS analyses. These findings show that electrochemical nanostructuring of GaN layers is a potentially attractive technology for the development of radiation hard devices

Treatment of anaerobic infection after caesarean section (case report)

Catedra chirurgie generală, USMF “Nicolae Testemiţanu”, Spitalul Clinic Municipal nr.1, Chişinău, Republica Moldova, Al XII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova cu participare internațională 23-25 septembrie 2015Introducere: Femeile care au suportat operaţia cezariană prezintă un risc de la 5 la 20 ori mai mare pentru complicaţii infecţioase, faţă de cele care nasc pe cale naturală. Complicaţiile includ endometritele (20-85% din cazuri), infecţia plăgii (25%), bacteriemia, abcesele pelviene, şocul septic, fasciitele necrotizante şi tromboflebitele venelor pelviene. Principalele microorganisme responsabile pentru endometrite sunt bacilii aerobi gram-negativi (E.coli); bacilii anaerobi gram-negativi (Bacteroides sp. şi Gardnerella vaginalis); cocii aerobi gram-pozitivi (streptococii din Grupul B şi Grupul D); şi cocii anaerobi gram-pozitivi (Peptococcus sp. şi Peptostreptococcus sp). Pe parcursul travaliului şi a naşterii abdominale endometriumul şi cavitatea peritoneală sunt invariabil contaminate cu un număr mare de bacterii patogene aerobe şi anaerobe care prolifere ază în lichidul peritoneal postoperator sero-sangvin. Caz clinic: Este raportat cazul unei femei obeze (IMC=40) cu vârsta de 39 ani, care a fost supusă operaţiei cezariene la a 13-a naştere. În pofida indicaţiilor nu au fost administrate antibiotice în scop profilactic nici până, nici după intervenţie. Peste 2 zile bolnava a fost transferată în secţia de chirurgie datorită dehiscenţei şi infecţiei plăgii. S-a recurs la histerectomie totală. Analiza bacteriologică a pus în evidenţă prezenţa Enterobacter aerogenus, Enterococcus sp. şi a Staphylococcus aureus. Pe parcursul a 28 de zile au fost administrate antibiotice în conformitate cu sensibilitatea patogenilor, concomitent cu tratamentul local al plăgii. Vindecarea completa a fost atestată în ziua a 56-a. Concluzie: În grupul de risc este strict indicată antibiotico-profilaxia peri-cezariană.Introduction: Women who undergo caesarean section have a 5 to 20-fold greater risk of infectious complications than those after normal vaginal delivery. The complications include endometritis (20-85% of cases), wound infection (25%), bacteremia, pelvic abscess, septic shock, necrotizing fasciitis, and septic pelvic vein thrombophlebitis. The main microorganisms responsible for endometritis are aerobic gram-negative bacilli (E.coli); anaerobic gram-negative bacilli (Bacteroides sp. and Gardnerella vaginalis); aerobic gram-positive cocci (Group B and Group D streptococci); and anaerobic gram-positive cocci (Peptococcus sp. and Peptostreptococcus sp). During labor and abdominal delivery, the endometrium and peritoneal cavity invariably are contaminated with large numbers of highly pathogenic aerobic and anaerobic bacteria which are proliferating in the serosanguineous postoperative peritoneal fluid. Clinical case: We report a case of an obese (BMI=40) 39 years old woman who suffered a caesarean section at 13th delivery. In spite of indications, no prophylactic antibiotics where administrated nor before neither after intervention. After 2 days she was transferred to the Surgical Department due to wound dehiscence and infection. Total hysterectomy was performed. Bacteriological analysis identified presence of Enterobacter aerogenus, Enterococcus sp. and Staphylococcus aureus. There were administrated antibiotics according to sensibility of the pathogens for 28 days, along with local debridement of the wound. After 56 days of hospitalization complete healing was reported. Conclusion: It is strictly indicated to use prophylactic antibiotic administration peri-caesarean section in the risk group