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Currently one of the main tools for the large scale studies of schools is statistical analysis. Although it is the most common method and it offers greatest opportunities for analysis, there are other quantitative methods for studying schools, such as network analysis. We discuss the potential advantages that network analysis has for educational research. [This article was translated by Kenneth Cargill.]

Using a laboratory micro-autoclave (of ~ 20 cm3 volume), the effects of transition metal additives (MoO3, Fe2O3 and commercial AlCoMo catalyst) on the thermal transformations of tile-like Barzas coals (sapromixites) in a hydrogen medium at T ~ 475°C and P ~ 6.0-7.5 MPa have been studied. It has been shown that catalytic additives under investigation somewhat suppress gas formation processes, facilitating the increase in H/C atomic ratios and in the amount of alkyl-containing structures in resin-like solid products of Barzas coal hydro-liquefaction. Maximal yields of “coal liquids” (maltenes + asphaltenes) (~ 35 wt.%, daf basis) were obtained during the heat treatment of sapromixites in the presence of bb1 wt.% MoO3.

Using FTIR spectroscopy, elemental analysis and gas chromatography methods, the temperature effects on the thermal transformations of low-metamorphosed Barzas coal (sapromixite) in carbon dioxide media have been studied. According to the IR spectroscopic data, an increase in the relative content of alkyl groups (-CH3 and >CH2) in the solid residue of sapromixite with a rise in the process temperature up to ~ 475°C was observed, followed by a rapid decrease in their concentration at higher heat treatment temperatures. Such behavior may be associated with an initial accumulation of alkyl fragments, formedfrom the coal matter, and their subsequent transition into the gaseous phase. A close relationship (an antibate dependence) has been discovered between H/C atomic ratios in resin-containing solid products of thermally treated Barzas coal and the yields of gases formed during its pyrolysis. Chromatographic analysis of liquid products formed after Barzas coal heat treatment at 475°C showed that the main organic constituents of liquid phase (about 3-5% by weight) were phenol and its methyl-and dimethyl derivatives (their total content in methylene chloride extract was of > 77% by weight).

The experimental setup for studying operation effectiveness of the closed two-phase thermosyphon s aimed at the development of heat exchangers without disturbing the process of air circulation inside the module of control system, which can maintain the required temperature that provides effective heat removal from the zone of module equipment are elaborated. The primary results of experimental researches are presented.

Non-parasitic splenic cysts account for 0.5-10% of diseases of this organ. Incidence of splenic cysts has increased in recent years that may be associated with widespread use of abdominal imaging. Symptoms are absent in most cases. Splenic cysts > 5 cm are prone to complications such as bleeding, rupture or infection. These patients require surgical treatment. The authors present multilocular splenic cyst in a 15-year-old patient. The girl was followed-up for 2 previous years due to asymptomatic small cyst. However, cyst enlargement required surgical treatment. Examination revealed multilocular cyst 7×10 cm in the upper pole of the spleen. Enzyme immunoassay did not reveal antibodies to echinococcus. Laparoscopic partial resection of spleen was performed. This case is an example of modern surgical approach for nonparasitic splenic cysts characterized by minimally invasive organ-sparing technologies.

The inner ear is a complex structure responsible for hearing and balance, and organ pathology is associated with deafness and balance disorders. To evaluate the role of epigenomic dynamics, we performed whole genome bisulfite sequencing at key time points during the development and maturation of the mouse inner ear sensory epithelium (SE). Our single-nucleotide resolution maps revealed variations in both general characteristics and dynamics of DNA methylation over time. This allowed us to predict the location of non-coding regulatory regions and to identify several novel candidate regulatory factors, such as Bach2, that connect stage-specific regulatory elements to molecular features that drive the development and maturation of the SE. Constructing in silico regulatory networks around sites of differential methylation enabled us to link key inner ear regulators, such as Atoh1 and Stat3, to pathways responsible for cell lineage determination and maturation, such as the Notch pathway. We also discovered that a putative enhancer, defined as a low methylated region (LMR), can upregulate the GJB6 gene and a neighboring non-coding RNA. The study of inner ear SE methylomes revealed novel regulatory regions in the hearing organ, which may improve diagnostic capabilities, and has the potential to guide the development of therapeutics for hearing loss by providing multiple intervention points for manipulation of the auditory system.

The peripheral deafness gene Mir96 is expressed in both the cochlea and central auditory circuits. To investigate whether it plays a role in the auditory system beyond the cochlea, we characterized homozygous Dmdo/Dmdo mice with a point mutation in miR-96. Anatomical analysis demonstrated a significant decrease in volume of auditory nuclei in Dmdo/Dmdo mice. This decrease resulted from decreased cell size. Non-auditory structures in the brainstem of Dmdo/Dmdo mice or auditory nuclei of the congenital deaf Cldn14-/- mice revealed no such differences. Electrophysiological analysis in the medial nucleus of the trapezoid body (MNTB) showed that principal neurons fired preferentially multiple action potentials upon depolarization, in contrast to the single firing pattern prevalent in controls and Cldn14-/- mice. Immunohistochemistry identified significantly reduced expression of two predicted targets of the mutated miR-96, Kv1.6 and BK channel proteins, possibly contributing to the electrophysiological phenotype. Microscopic analysis of the Dmdo/Dmdo calyx of Held revealed a largely absent compartmentalized morphology, as judged by SV2-labeling. Furthermore, MNTB neurons from Dmdo/Dmdo mice displayed larger synaptic short-term depression, slower AMPA-receptor decay kinetics and a larger NMDA-receptor component, reflecting a less matured stage. Again, these synaptic differences were not present between controls and Cldn14-/- mice. Thus, deafness genes differentially affect the auditory brainstem. Furthermore, our study identifies miR-96 as an essential gene regulatory network element of the auditory system which is required for functional maturation in the peripheral and central auditory system alike.

Mammalian genomes encode multiple layers of regulation, including a class of RNA molecules known as long non-coding RNAs (lncRNAs). These are >200 nucleotides in length and similar to mRNAs, they are capped, polyadenylated, and spliced. In contrast to mRNAs, lncRNAs are less abundant and have higher tissue specificity, and have been linked to development, epigenetic processes, and disease. However, little is known about lncRNA function in the auditory and vestibular systems, or how they play a role in deafness and vestibular dysfunction. To help address this need, we performed a whole-genome identification of lncRNAs using RNA-seq at two developmental stages of the mouse inner ear sensory epithelium of the cochlea and vestibule. We identified 3,239 lncRNA genes, most of which were intergenic (lincRNAs) and 721 are novel. We examined temporal and tissue specificity by analyzing the developmental profiles on embryonic day 16.5 and at birth. The spatial and temporal patterns of three lncRNAs, two of which are in proximity to genes associated with hearing and deafness, were explored further. Our findings indicate that lncRNAs are prevalent in the sensory epithelium of the mouse inner ear and are likely to play key roles in regulating critical pathways for hearing and balance.

Background: The quantitative relations between RNA and protein are fundamental to biology and are still not fully understood. Across taxa, it was demonstrated that the protein-to-mRNA ratio in steady state varies in a direction that lessens the change in protein levels as a result of changes in the transcript abundance. Evidence for this behavior in tissues is sparse. We tested this phenomenon in new data that we produced for the mouse auditory system, and in previously published tissue datasets. A joint analysis of the transcriptome and proteome was performed across four datasets: inner-ear mouse tissues, mouse organ tissues, lymphoblastoid primate samples and human cancer cell lines., Results: We show that the protein levels are more conserved than the mRNA levels in all datasets, and that changes in transcription are associated with translational changes that exert opposite effects on the final protein level, in all tissues except cancer. Finally, we observe that some functions are enriched in the inner ear on the mRNA level but not in protein., Conclusions: We suggest that partial buffering between transcription and translation ensures that proteins can be made rapidly in response to a stimulus. Accounting for the buffering can improve the prediction of protein levels from mRNA levels.

The planar cell polarity (PCP) pathway is responsible for polarizing and orienting cochlear hair cells during development through movement of a primary cilium, the kinocilium. GPSM2/LGN, a mitotic spindle-orienting protein associated with deafness in humans, is a PCP effector involved in kinocilium migration. Here, we link human and mouse truncating mutations in the GPSM2/LGN gene, both leading to hearing loss. The human variant, p.(Trp326*), was identified by targeted genomic enrichment of genes associated with deafness, followed by massively parallel sequencing. Lgn (ΔC) mice, with a targeted deletion truncating the C-terminal GoLoco motifs, are profoundly deaf and show misorientation of the hair bundle and severe malformations in stereocilia shape that deteriorates over time. Full-length protein levels are greatly reduced in mutant mice, with upregulated mRNA levels. The truncated Lgn (ΔC) allele is translated in vitro, suggesting that mutant mice may have partially functioning Lgn. Gαi and aPKC, known to function in the same pathway as Lgn, are dependent on Lgn for proper localization. The polarization of core PCP proteins is not affected in Lgn mutants; however, Lgn and Gαi are misoriented in a PCP mutant, supporting the role of Lgn as a PCP effector. The kinocilium, previously shown to be dependent on Lgn for robust localization, is essential for proper localization of Lgn, as well as Gαi and aPKC, suggesting that cilium function plays a role in positioning of apical proteins. Taken together, our data provide a mechanism for the loss of hearing found in human patients with GPSM2/LGN variants.