Collective Charge Excitations below the Metal-to-Insulator Transition in BaVS3

The charge response in the barium vanadium sulfide (BaVS3) single crystals is characterized by dc resistivity and low frequency dielectric spectroscopy. A broad relaxation mode in MHz range with huge dielectric constant ~= 10^6 emerges at the metal-to-insulator phase transition TMI ~= 67 K, weakens with lowering temperature and eventually levels off below the magnetic transition Tchi ~= 30 K. The mean relaxation time is thermally activated in a manner similar to the dc resistivity. These features are interpreted as signatures of the collective charge excitations characteristic for the orbital ordering that gradually develops below TMI and stabilizes at long-range scale below Tchi.Comment: 6 pages, 3 figures, submitted to PR

Strictly nonclassical behavior of a mesoscopic system

We experimentally demonstrate the strictly nonclassical behavior in a many-atom system using a recently derived criterion [E. Kot et al., Phys. Rev. Lett. 108, 233601 (2012)] that explicitly does not make use of quantum mechanics. We thereby show that the magnetic moment distribution measured by McConnell et al. [R. McConnell et al., Nature 519, 439 (2015)] in a system with a total mass of $2.6\times 10^5$ atomic mass units is inconsistent with classical physics. Notably, the strictly nonclassical behavior affects an area in phase space $10^3$ times larger than the Planck quantum $\hbar$.Comment: 5 page

Geographical Distribution of Elderly People in Croatia

The authors outlined the geographical distribution of individuals displaying longevity in the Republic of Croatia. Elderly people, aged 80 years and older, have been the subject of this study and were viewed in several aspects including the number of elderly people and age-specific mortality rate by districts. Data for the years 1981 and 1991 were reviewed. In 1981 there were 73,052 (1.6%) persons aged 80 or older. Ten years later in 1991 their number had increased to 107,256, which was 2.2% of the whole population. Most of the elderly people live on the islands, in the district of Dubrovnik and in Lika, which is in the continental part of Croatia. There are more women than men among those aged 80 years and older. Age-specific mortality rate in 1981 in Croatia was 170 and in 1991 151 per 1,000 elderly people. In women the rate was 162 in 1981 and 141 in 1991, per 1,000 elderly people. The death rate was higher in men; in 1981 it was 201 and in 1991, 172 per 1,000 elderly people. We can see that the specific mortality rate had fallen in 1991 compared to 1981. The age specific mortality rate varies from district to district. In 1991 the lowest, 110 per 1,000, was in Lika, and the highest in the districts of Vara`din (182 per 1,000), Bjelovar (178 per 1,000) and Zagorje (175 per 1,000). The death rate was higher amongst elderly men (172.31 per 1,000) than elderly women (141.65 per 1,000). The smallest number of those aged 80 years and older with a high death rate is found in Slavonia. The opposite – a high number of elderly people and a low specific mortality rate – can be seen in the district of Lika. On the islands the number of elderly people is high, especially women, and surprisingly, the specific mortality rate is relatively high as well

Significance of leptin receptor expression in cell proliferation, neoangiogenesis and organization of elastic fibers in squamocellular carcinoma of the skin

Adipokin leptin ostvaruje funkcije preko svojih transmembranskih receptora (LEPR). U brojnim malignim tumorima stimuliše rast, migraciju i invazivnost malignih ćelija. Cilj našeg rada je utvrditi značaj ekspresije receptora za leptin u ćelijskoj proliferaciji, neoangiogenezi i organizaciji elastičnih vlakana u skvamocelularnom karcinomu kože (cSCC). Korišćen je biopsijski materijal dobijen ekscizijom skvamocelularnog karcinoma kože. Ispitivanu grupu su činile ekscizione biopsije skvamocelularnog karcinoma kože (n=62), a kontrolnu grupu (n=62) su činile ekscizione biopsije netumorskog tkiva kože (iz okoline tumora). Nakon rutinske obrade i kalupljenja u parafin, na presecima debljine 4 µm su primenjene histohemijske Hematoxylin-Eosin, Verhoeff – Van Gieson i imunohistohemijska ABC metoda sa anti LEPR, Ki67, p53, CD34 i Cytokeratin AE1/AE3 antitelima. Za analizu dobijenih rezultata korišćen je statistički programski paket SPSS za Windows (26.0). LEPR ekspresija je značajno povezana sa indeksom proliferacije i mikrovaskularne gustine, histološkim gradusom tumora i količinom i karakteristikama elastičnih vlakana u peritumorskom tkivu. Izražena LEPR ekspresija je u 50% tumora udružena sa većom količinom isprekidanih i zadebljalih elastičnih vlakana, u 66,7% sa visokim indeksom proliferacije, 70% sa visokim indeksom mikrovaskularne gustine, i u 94,4% slučajeva sa loše diferentovanim cSCC. Multivarijantna regresiona analiza je pokazala da su cSCC sa izraženom LEPR ekspresijom sedam puta češće loše diferentovani od tumora sa umerenom ili LEPR ekspresijom u tragu. Naši rezultati ukazuju da je LEPR ekspresija prediktor malignog potencijala cSCC, pa je na osnovu LEPR ekspresije moguće identifikovati agresivan fenotip ovih tumora, što pruža mogućnost individualizacije antitumorskog tretmana primenom antagonista LEPR.Adipokin leptin performs functions through its transmembrane receptors (LEPR). In numerous malignant tumors, it stimulates the growth, migration and invasiveness of malignant cells. The aim of our study was to determine the significance of leptin receptor expression in cellular proliferation, neoangiogenesis, and elastic fiber organization in squamous cell carcinoma of the skin (cSCC). Biopsy material obtained by excision of squamous cell carcinoma of the skin was used. The study group consisted of excisional biopsies of squamous cell skin cancer (n = 62), and the control group (n = 62) consisted of excisional biopsies of non-tumor skin tissue (from the tumor environment). After routine processing and molding into paraffin, histochemical HematoxylinEosin, Verhoeff - Van Gieson and immunohistochemical ABC methods with anti-LEPR, Ki67, p53, CD34 and Cytokeratin AE1 / AE3 antibodies were applied on 4 µm thick sections. The statistical software package SPSS for Windows (26.0) was used to analyze the obtained results LEPR expression is significantly associated with proliferation index and microvascular density, tumor histological grade, and the amount and characteristics of elastic fibers in peritumoral tissue. Significant LEPR expression is associated in 50% of tumors with higher amounts of ruptured and thickened elastic fibers, in 66.7% with high proliferation index, 70% with high microvascular density index, and in 94.4% of cases with poorly differentiated cSCC. Multivariate regression analysis showed that cSCCs with pronounced LEPR expression were seven times more often poorly differentiated than tumors with moderate or trace LEPR expression. Our results indicate that LEPR expression is a predictor of malignant cSCC potential, so based on LEPR expression it is possible to identify the aggressive phenotype of these tumors, which provides the possibility of individualization of antitumor treatment using LEPR antagonists

Anisotropic Charge Modulation in Ladder Planes of Sr_14-xCa_xCu_24O_41

The charge response of the ladders in Sr_14-xCa_xCu_24O_41 is characterized by dc resistivity, low frequency dielectric and optical spectroscopy in all three crystallographic directions. The collective charge-density wave screened mode is observed in the direction of the rungs for x=0, 3 and 6, in addition to the mode along the legs. For x=8 and 9, the charge-density-wave response along the rungs fully vanishes, while the one along the legs persists. The transport perpendicular to the planes is always dominated by hopping.Comment: 4 pages, 3 figures, submitted to PRB R

Ultracold molecules: vehicles to scalable quantum information processing

We describe a novel scheme to implement scalable quantum information processing using Li-Cs molecular state to entangle $^{6}$Li and $^{133}$Cs ultracold atoms held in independent optical lattices. The $^{6}$Li atoms will act as quantum bits to store information, and $^{133}$Cs atoms will serve as messenger bits that aid in quantum gate operations and mediate entanglement between distant qubit atoms. Each atomic species is held in a separate optical lattice and the atoms can be overlapped by translating the lattices with respect to each other. When the messenger and qubit atoms are overlapped, targeted single spin operations and entangling operations can be performed by coupling the atomic states to a molecular state with radio-frequency pulses. By controlling the frequency and duration of the radio-frequency pulses, entanglement can either be created or swapped between a qubit messenger pair. We estimate operation fidelities for entangling two distant qubits and discuss scalability of this scheme and constraints on the optical lattice lasers

The Effect of a Compulsory Curriculum on Ethical Attitudes of Medical Students

The purpose of the present study was to assess the influence of a compulsory curriculum on first-year medical students. The ethical attitude study was performed at the School of Medicine, University of Rijeka, Croatia. The samples consisted of 171 medical students (68 males and 103 females) interviewed at the beginning of the first year of studies. Some of them, namely 143 (56 males and 87 females) were interviewed again at the end of the same academic year. Data were analysed by applying factor analysis under principal component model and varimax criterion as the rotation model. The results clearly show that the current compulsory curriculum without formal ethical education has a limited influence on first-year medical students. That points to the obvious necessity to implement the medical ethics in the course of medical education

Suppression of the charge-density-wave state in Sr_14Cu_24O_41 by calcium doping

The charge response in the spin chain/ladder compound Sr_14-xCa_xCu_24O_41 is characterized by DC resistivity, low-frequency dielectric spectroscopy and optical spectroscopy. We identify a phase transition below which a charge-density wave (CDW) develops in the ladder arrays. Calcium doping suppresses this phase with the transition temperature decreasing from 210 K for x=0 to 10 K for x=9, and the CDW gap from 130 meV down to 3 meV, respectively. This suppression is due to the worsened nesting originating from the increase of the inter-ladder tight-binding hopping integrals, as well as from disorder introduced at the Sr sites. These results altogether speak in favor of two-dimensional superconductivity under pressure.Comment: 4 pages, 4 figures, accepted for publication in PR