High-Mobility, Ultrathin Organic Semiconducting Films Realized by Surface-Mediated Crystallization.

The functionality of common organic semiconductor materials is determined by their chemical structure and crystal modification. While the former can be fine-tuned via synthesis, a priori control over the crystal structure has remained elusive. We show that the surface tension is the main driver for the plate-like crystallization of a novel small organic molecule n-type semiconductor at the liquid-air interface. This interface provides an ideal environment for the growth of millimeter-sized semiconductor platelets that are only few nanometers thick and thus highly attractive for application in transistors. On the basis of the novel high-performance perylene diimide, we show in as-grown, only 3 nm thin crystals electron mobilities of above 4 cm2/(V s) and excellent bias stress stability. We suggest that the established systematics on solvent parameters can provide the basis of a general framework for a more deterministic crystallization of other small molecules.

[Opine biosynthesis and catabolism genes of Agrobacterium tumefaciens and Agrobacterium rhizogenes].

Agrobacterium is a genus of soil bacteria with the ability to transform plant cells by a T-DNA-sequence located on the pTi/pRi- plasmid containing a set of genes expressed in plant cells. Expression of these genes leads to a proliferation of transformed cells, with the subsequent formation of tumors or growths of roots and the synthesis of opines--products of the condensation of amino acids with ketoacids or sugars used by Agrobacteria as a source of carbon and nitrogen. In this review, we systematized the information about most common opines in plant--Agrobacterium systems and their biosynthesis and catabolism genes, as well as the role of opines in the interaction of pathogenic Agrobacterium with plants and with other Agrobacterium strains, including the genetic consequences of such interactions.

[Genetics of anthocyaninless rye].

Six nonallelic genes have been discovered in rye, the recessive mutations of which lead to a lack of anthocyanin. Crosses with these mutants showed that 13 new anthocyaninless lines carry mutations in the gene vi1, whereas vi2/6 mutations were identified only in single cases. Inheritance of the vi1/6 mutations in the progeny of hybrids with the wild type (Line 7, L7) corresponds to a monohybrid segregation. Segregation for three of these mutations (vi2, vi4, and vi5) in hybrids with line 2 is characterized by anthocyaninless deficiency in plants. We discuss the reasons for such deviations and the previously published data for the identification of the six anthocyanin pigmentation genes in the rye using trisomic analysis.

[First live birth in Bulgaria after in vitro maturation (IVM) procedure (case report)].

The objective is to report the first healthy live birth in Bulgaria from immature oocytes retrieved in a natural menstrual cycle, followed by in vitro maturation (IVM). In vitro maturation protocol was performed in a case with male factor of infertility. Twentyone immature oocytes were retrieved by transvaginal ultrasound guided follicle aspiration on day 10 of a 28-year-old woman and matured in vitro. 28 hours late, 14 of them were in metaphase II. After insemination 13 were fertilizated. Three embryos were transfered at day two. The woman went on to deliver a single healthy live baby at term. We provide proof-of-principle evidence that the novel strategy of infertility treatment by IVM protocol can lead to successful pregnancy and healthy live birth.

Energy barriers at grain boundaries dominate charge carrier transport in an electron-conductive organic semiconductor.

Semiconducting organic films that are at the heart of light-emitting diodes, solar cells and transistors frequently contain a large number of morphological defects, most prominently at the interconnects between crystalline regions. These grain boundaries can dominate the overall (opto-)electronic properties of the entire device and their exact morphological and energetic nature is still under current debate. Here, we explore in detail the energetics at the grain boundaries of a novel electron conductive perylene diimide thin film. Via a combination of temperature dependent charge transport measurements and ab-initio simulations at atomistic resolution, we identify that energetic barriers at grain boundaries dominate charge transport in our system. This novel aspect of physics at the grain boundary is distinct from previously identified grain-boundary defects that had been explained by trapping of charges. We furthermore derive molecular design criteria to suppress such energetic barriers at grain boundaries in future, more efficient organic semiconductors.

Anesthesia, surgical aid and resuscitation in manned space missions.

When discussing problems related to medical service in space flight, particular attention should be given to the specific living conditions and changes associated with space flight. In disease and injury, surgery can be provided only after conservative therapy has failed. In this context gnotobiological chambers allowing surgery in aseptic conditions seem promising. A portable set of interchangeable surgical tools should be made of light-weight alloys that can be readily sterilized. Electroanalgesia in combination with auriculoacupuncture as well as peridureal anesthesia may be used as they allow normal operations in autonomous space flight conditions. Changes in the sympatho-adrenal and kallikrein-kinin systems, as well as water-electrolyte balance, should be taken into account in developing methods and means of medical service in critical situations. Special attention should be given to the prevention and treatment of brain edema in view of weightlessness-induced cephalad fluid shifts.

[Problems of anesthesia, surgical care and resuscitation during manned space flights]. / Problemy obezbolivaniia, khirurgicheskoi pomoshchi i reanimatsii vo vormia piolotiruemykh kosicheskikh poletov.

When exploring the problems of medical aid to be rendered in manned space flights, it is necessary to take into consideration the specific features of the environment as well as the changes in the human body induced by space flight effects. In space flight anesthesia can be applied using such advanced methods as multi-component balanced anesthesia and peridural anesthesia. Surgery and resuscitation can be performed, employing the procedures and methods that allow operations in an abacterial environment, correction of vital dysfunctions with the aid of artificial pulmonary ventilation, cardiac electrotherapy, and sorptive purification of body fluids. Various aspects of infusion treatment and first medical aid are discussed.