Skeletopic analysis of the gonadal veins in human foetuses

During ontogenesis an imbalance is observable in the development of the skeletal and vascular systems. By means of anatomical and radiological methods the gonadal veins were studied in relation to the vertebral column in 60 human foetuses of both sexes aged from 4 to 6 months of prenatal life. In male foetuses aged 4–5 months the origin of the gonadal veins projected onto the sacral apex (r1 = 0.95, r3 = 0.85), and in 6th month they extended below the vertebral column (r1’ = 0.80, r3’ = 0.90). In female foetuses the origin of the gonadal veins in the 4th month projected symmetrically onto S1 (r5 = 0.70, r7 = 0.70). In the 5th month of intrauterine life the origin of the left ovarian vein was found at S2 (r7’ = 0.80) and the origin of the right one at S1–S2 (r5’ = 0.80). In the 6th month the origin of the left ovarian vein was located at S3 (r7’ = 0.80) and the right one at S2–S3 (r5’’ = 0.90). The skeletopic analysis of the origin of the gonadal veins demonstrated gender (the origin was higher in females) and syntopic (the origin was higher on the right side) differences (p ≤ 0.05). In foetuses of both sexes aged 4 months of prenatal life the termination of the left gonadal veins projected onto Th12–L1 (r4 = 0.85, r8 = 0.80) and in foetuses aged 5–6 months it projected onto L1–L2 (r4’ = 0.90, r8’ = 0.95). In both sexes the termination of the gonadal veins on the right side projected constantly onto L2 (r2 = 0.90, r6 = 0.95) from the 4th to the 6th month of intrauterine life. The skeletopic analysis of the termination of the gonadal veins showed syntopic dimorphism (p ≤ 0.05) without gender differences (p > 0.05). On the right side the termination of the gonadal (testicular and ovarian) veins projected constantly onto L2. On the left side the termination of the left gonadal (testicular and ovarian) veins apparently descended by one vertebra (pseudodescensus)

The retroperitoneal anastomoses of the gonadal veins in human foetuses

In the retroperitoneal space the gonadal veins form a collateral circulation that has a great clinical impact on sclerotherapy or surgical ligation of varicoceles. The aim of this study was to examine the communications of the gonadal veins (according to classification, frequency of appearance, gender and syntopic differences) in human foetuses of both sexes (71 males and 59 females) aged 4–6 months of intrauterine life. On the right side the most frequently were found the gonadal-periureteral anastomosis (23%) and the gonadal-perirenal anastomosis (22%). A gonadal-lumbar anastomosis on the right side appeared in 7% of cases. On the left side the most frequent (37%) was the gonadalperirenal anastomosis, more frequently occurring as an ovarian-perirenal anastomosis (48%) than as a testicular-perirenal anastomosis (29%). Gonadal-periureteral anastomoses were found in a quarter of cases. Gonadal-lumbar anastomoses were observed in 7% of individuals. On the left side the gonadal-mesenteric inferior anastomosis was specifically observed (21%) as an ovarian-mesenteric inferior anastomosis (24%) and a testicular-mesenteric inferior anastomosis (19%). The cross-communications between the right and left gonadal veins (7%) were more frequently as the bilateral testicular (9.7%) than as the bilateral ovarian one (3%). In female foetuses gonadal-perirenal anastomoses occurred with statistically greater frequency than gonadal-periureteral anastomoses (p ≤ 0.05). The frequency of cross-communications of the gonadal veins was three times greater in male foetuses (p ≤ 0.01). Statistical analysis revealed a significantly greater frequency of left-sided anastomoses: the gonadal-perirenal in both sexes (p ≤ 0.05), the gonadal-periureteral in males (P ≤ 0.05) and the gonadalmesenteric inferior in both sexes (p ≤ 0.01)

Depth concentrations of deuterium ions implanted into some pure metals and alloys

Pure metals (Cu, Ti, Zr, V, Pd) and diluted Pd-alloys (Pd-Ag, Pd-Pt, Pd-Ru, Pd-Rh) were implanted by 25 keV deuterium ions at fluences in the range (1.2{\div}2.3)x1022 D+/m2. The post-treatment depth distributions of deuterium ions were measured 10 days and three months after the implantation using Elastic Recoil Detection Analysis (ERDA) and Rutherford Backscattering (RBS). Comparison of the obtained results allowed to make conclusions about relative stability of deuterium and hydrogen gases in pure metals and diluted Pd alloys. Very high diffusion rates of implanted deuterium ions from V and Pd pure metals and Pd alloys were observed. Small-angle X-ray scattering revealed formation of nanosized defects in implanted corundum and titanium.Comment: 12 pages, 9 figure

CO 2 - reinforced nanoporous carbon potential energy field during CO 2 /CH 4 mixture adsorption. A comprehensive volumetric, in-situ IR, and thermodynamic insight

CO2/CH4 mixture adsorption is very important in different fields like, for example, a biogas purification. Using a comprehensive experimental approach based on volumetric and in-situ FTIR measurements the new results of CO2/CH4 mixture separation on a carbon film are reported. The application of this experimental approach makes it possible to elaborate the effect of enhanced CH4 adsorption at low CO2 concentrations in the adsorbed phase. The presence of this effect is proved experimentally for the first time. This effect is responsible for the deviation of Ideal Adsorption Solution model from the experimental data. To discuss separation mechanism the activity coefficients at constant spreading pressure values are calculated. At low spreading pressure, CO2 activity coefficient is strongly disturbed by the presence of CH4 molecules in the surface mixture. In contrast, the CH4 activity coefficients are remarkably influenced by adsorbed CO2 only at higher CO2 surface concentrations. The obtained activity coefficients are successfully described by a new modification of the Redlich-Kister equation. This modification takes into account the interaction between binary mixture components and an adsorbent. Finally we show that the studied carbon possesses very good CO2/CH4 mixture separation properties, comparable to those reported for other adsorbents

Digital-image analysis of the left common carotid artery in human foetuses

The rate of growth of the left common carotid artery during gestation has not been sufficiently evaluated. The present study was performed on 128 spontaneously aborted human foetuses aged 15&#8211;34 weeks to compile normative data for the dimensions of the left common carotid artery at varying gestational ages. Using anatomical dissection, digital image analysis (system of Leica Q Win Pro 16) and statistical analysis (ANOVA, regression analysis), a range of measurements (length, original external diameter and volume) for the left common carotid artery during gestation was examined. No significant gender differences were found (p > 0.05). The growth curves of the best fit for the plot of each morphometric parameter against gestational age were generated. The lengths ranged from 14.82 &#177; 2.22 to 42.84 &#177; 4.32 mm, according to the linear model y = -9.6918 + 1.5963 x &#177; 3.1706 (r = 0.95; p < 0.001). The original external diameter increased from 0.72 &#177; 0.18 to 3.28 &#177; 0.40 mm, according to the linear function y = &#8211;1.5228 + 0.1428 x &#177; 0.2749 (r = 0.95; p < 0.001). The left common carotid artery-to-aortic root diameter ratio increased from 0.356 &#177; 0.062 to 0.480 &#177; 0.101. The left common carotid artery-to-aortic arch diameter ratio increased from 0.447 &#177; 0.079 to 0.535 &#177; &#177; 0.113. The volume ranged from 6.73 &#177; 4.06 to 369.30 &#177; 107.42 mm3 in accordance with the quadratic function y = 344.8 &#8211; 41.001 x + 1.254 x2 &#177; &#177; 46.955 (R2 = 0.87). The parameters examined have clinical application in the early recognition of arterial abnormalities, especially aortic coarctation

Stability of coordination polymers in water: state of the art and towards a methodology for nonporous materials

A mini review on the study concerning water stability of coordination polymers (CPs) is presented. Next, following the procedure proposed recently by Gelfand and Shimizu (Dalton Trans 45:3668-3678, 2016) the stability of three cysteine (Cys)containing CPs is investigated. The stability of studied CPs decreases in the order: Zn(Cys)(2)>Mg(Cys)(2)>Ca(Cys)(2) H2O. For the latternever reported before, the structure is additionally determined and it is proved that water is located in the first coordination sphere. It is shown that for nonporous CPs, in contrast to the porous ones, the immersion in water at 20 degrees C is more drastic for studied solids than the harsh humid conditions (80 degrees C at 90% R.H.). Finally all materials are assigned to the hydrolytic stability groups and it is concluded that the stability of studied CPs correlates well with the standard reduction potentials. This leads to the conclusion that the application of more inert metal as a node causes larger stability of studied CPs

Superexchange Interaction in Insulating EuZn2_{2}P2_{2}

We report magnetic and transport properties of single-crystalline EuZn$_{2}$P$_{2}$, which has trigonal CaAl$_2$Si$_2$-type crystal structure and orders antiferromagnetically at $\approx$23~K. Easy $ab$-plane magneto-crystalline anisotropy was confirmed from the magnetization isotherms, measured with a magnetic field applied along different crystallographic directions ($ab$-plane and $c$-axis). Positive Curie-Weiss temperature indicates dominating ferromagnetic correlations. Electrical resistivity displays insulating behavior with a band-gap of $\approx\,$0.177~eV, which decreases to $\approx\,$0.13~eV upon application of a high magnetic field. We explained the intriguing presence of magnetic interactions in an intermetallic insulator by the mechanism of extended superexchange, with phosphorus as an anion mediator, which is further supported by our analysis of the charge and spin density distributions. We constructed the effective Heisenberg model, with exchange parameters derived from the \textit{ab initio} DFT calculations, and employed it in Monte-Carlo simulations, which correctly reproduced the experimental value of N\'eel temperature

Curious Variables Experiment (CURVE). CCD photometry of active dwarf nova DI UMa

We report an analysis of photometric behaviour of DI UMa, an extremely active dwarf nova. The observational campaign (completed in 2007) covers five superoutbursts and four normal outbursts. We examined principal parameters of the system to understand peculiarities of DI UMa, and other active cataclysmic variables. Based on precise photometric measurements, temporal light curve behaviour, O-C analysis, and power spectrum analysis, we investigated physical parameters of the system. We found that the period of the supercycle now equals 31.45 +/-0.3 days. Observations during superoutbursts infer that the period of superhumps equals P_sh = 0.055318(11) days (79.66 +/- 0.02 min). During quiescence, the light curve reveals a modulation of period P_orb = 0.054579(6) days (78.59 +/- 0.01 min), which we interpret as the orbital period of the binary system. The values obtained allowed us to determine a fractional period excess of 1.35% +/- 0.02%, which is surprisingly small compared to the usual value for dwarf novae (2%-5%). A detailed O-C analysis was performed for two superoutbursts with the most comprehensive coverage. In both cases, we detected an increase in the superhump period with a mean rate of dot_P/P_sh = 4.4(1.0)*10^{-5}. Based on these measurements, we confirm that DI UMa is probably a period bouncer, an old system that reached its period minimum a long time ago, has a secondary that became a degenerate brown dwarf, the entire system evolving now toward longer periods. DI UMa is an extremely interesting object because we know only one more active ER UMa star with similar characteristics (IX Dra).Comment: Accepted for publication in Astronomy & Astrophysic