Importance of In-Plane Anisotropy in the Quasi Two-Dimensional Antiferromagnet BaNi2_{2}V2_{2}O8_{8}

The phase diagram of the quasi two-dimensional antiferromagnet BaNi$_{2}$V$_{2}$O$_{8}$ is studied by specific heat, thermal expansion, magnetostriction, and magnetization for magnetic fields applied perpendicular to $\mathbf{c}$. At $\mu_0H^{*}\simeq1.5$ T, a crossover to a high-field state, where $T_N(H)$ increases linearly, arises from a competition of intrinsic and field-induced in-plane anisotropies. The pressure dependences of $T_N$ and $H^{*}$ are interpreted using the picture of a pressure-induced in-plane anisotropy. Even at zero field and ambient pressure, in-plane anisotropy cannot be neglected, which implies deviations from pure Berezinskii-Kosterlitz-Thouless behavior.Comment: 4 pages, 4 figure

Double superconducting transition in the filled skutterudite PrOs4Sb12 and sample characterizations

A thorough characterization of many samples of the filled skutterudite compound PrOs4Sb12 is provided. We find that the double superconducting transition in the specific heat Tc1~1.89K and Tc2~1.72K tends to appear in samples with a large residual resistivity ratio, large specific heat jump at the superconducting transition and with the highest absolute value of the specific heat above Tc1. However, we present evidence which casts doubt on the intrinsic nature of the double superconducting transition. The ratio of the two specific heat jumps \Delta C(Tc1)/\Delta C(Tc2) shows a wide range of values on crystals from different batches but also within the same batch. This ratio was strongly reduced by polishing a sample down to 120um. Remarkably, three samples exhibit a single sharp transition of ~15mK in width at Tc~1.7K. The normalized specific heat jump (C-Cnormal)/Cnormal at Tc of two of them is higher than ~32% so larger than the sum of the two specific heat jumps when a double transition exists. As an evidence of better quality, the slope in the transition is at least two time steeper. We discuss the origins of the double transition; in particular we consider, based on X-ray diffraction results, a scenario involving Pr-vacancies. The superconducting phase diagram under magnetic field of a sample with a single transition is fitted with a two-band model taking into account the good values for the gap as deduced from thermal conductivity measurements.Comment: 10 pages, 9 figures, 2 tables, submitted to Physical review

Corporate networks in Poland: interlocking directorates and business systems

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and EconomicsAiming at filling a gap in the literature, which has been concentrated on USA and Western-European Countries, this paper analyzes the Polish corporate network based on interlocking directorates among 125 top companies in the country. To determine the characteristics of the network and its implications for the business system the exploratory Social Network Analysis is conducted. It is found that the Polish network is fragmented and the interlocks appear mainly along companies from financial and chemical sectors. Basing on comparison with Germany it is suggested that the Polish network will be growing in size and density in the future

How the Grateful Dead Turned Alternative Business and Legal Strategies Into A Great American Success Story

That the Grateful Dead were different undoubtedly is true on a broad social level. But it is not so easy to ascertain how they were different in the business and legal aspects of their enterprise. The ephemeral nature of their approach stems from the fact that they conducted their affairs within and alongside the world of statutes and contracts and yet provided themselves with a great degree of independence from that world. This Note will comment on the Dead\u27s perspective on and their ultimate rejection of many of the business and legal strategies traditionally ascribed to in the industry. After a brief introduction to the ethos of the Grateful Dead--essential as a frame of reference into their collective character--this Note will provide summaries of common music industry practices involved in signing onto a recording label and getting one\u27s material marketed, distributed, and sold. It will then examine the law that protects exposure of artists and their work. The reader should keep in mind that the law views songwriters and recording artists as separate entities. In practice, this distinction applies in most instances. This Note, however, will assume that these parties are one and the same, partly because the Dead both wrote and recorded their material, and partly to avoid the inconvenience and redundancy of having to draw out this distinction in passim

Galanin modulates oxytocin release from rat hypothalamo-neurohypophysial explant in vitro — the role of acute or prolonged osmotic stimulus

Wstęp: Galanina (Gal) jako neuromodulator różnych procesów w ośrodkowym układzie nerwowym może być zaangażowana w regulacji funkcji części nerwowej przysadki. Celem obecnych doświadczeń było zbadanie wpływu Gal na uwalnianie oksytocyny (OT) in vitro: zastosowano ostry lub przewlekły bodziec osmotyczny jako czynnik pobudzający. Materiał i metody: Badania zostały przeprowadzone na 3-miesięcznych szczurach samcach, od których pobierano podwzgórze (Hth), część nerwową przysadki (NH) lub układ podwzgórzowo-przysadkowy (Hth-NH). Wpływ Gal na uwalnianie OT był badany w warunkach braku pobudzenia osmotycznego — stymulacja jonami K+ (seria 1), podczas ostrego pobudzenia osmotycznego wywołanego jonami Na+ zawartymi w płynie inkubacyjnym (seria 2) lub w trakcie stymulacji osmotycznej o charakterze pośrednim, kiedy tkanki nerwowe pobierano od zwierząt otrzymujących do picia 2% roztwór NaCl (stan przewodnienia hipertonicznego) (seria 3). Zawartość OT oznaczano metodą radioimmunologiczną. Wyniki: Seria 1: Galanina obecna w medium inkubacyjnym hamowała podstawowe uwalnianie OT z NH i układu Hth-NH, natomiast pobudzała podstawowe i stymulowane jonami K+ uwalnianie OT z Hth. Seria 2: Gal nie wywierała żadnego wpływu na sekrecję OT indukowaną jonami Na+ zawartymi w płynie inkubacyjnym. Seria 3: Gal była przyczyną wzrostu podstawowego uwalniania OT z NH oraz stymulowanego jonami potasu uwalniania OT z Hth oraz układu Hth-NH pobranych od szczurów w stanie przewodnienia hipertonicznego. Wnioski: Na podstawie obecnych badań in vitro można przyjąć, że: 1. Gal pełni funkcję neuromodulatora hamującego uwalnianie OT z części nerwowej przysadki, natomiast wywiera efekt przeciwny na poziomie podwzgórza. 2. Gal działa jako neuromodulator pobudzający uwalnianie OT w odpowiedzi na stan przewlekłego pobudzenia osmotycznego; ostry bodziec osmotyczny blokuje wrażliwość neuronów OT-ergicznych na działanie galaniny. (Endokrynol Pol 2013; 64 (2): 139–148)Introduction: Galanin (Gal) may be involved as the neuromodulator of different processes in the central nervous system in the regulation of neurohypophysial function. The aim of the present study was to examine the influence of Gal on oxytocin (OT) release in vitro: an acute or prolonged osmotic stimulus was used as the stimulatory agent. Material and methods: Experiments were carried out on three-month old male rats which acted as donors of isolated rat hypothalamus (Hth), neurohypophysis (NH) or hypothalamo-neurohypophysial explants (Hth-NH). The effect of Gal on OT secretion was studied under conditions of non-osmotic (i.e. K+-evoked) (series 1), direct osmotic (i.e. Na+-evoked) (series 2) or indirect osmotic stimulation (series 3; neural tissues were obtained from animals drinking 2% NaCl). OT content was determined by radioimmunoassay. Results: Galanin added into incubative media caused the inhibition of basal OT release from NH and Hth-NH explants prepared from euhydrated rats but stimulated basal and K+-stimulated OT release from the Hth tissue. Gal did not exert any influence on Na+-evoked OT secretion. We observed increased basal OT secretion from NH and K+-evoked respective OT release from Hth and Hth-NH explants taken from osmotically challenged rats under the influence of Gal. Conclusions: Present experiments in vitro show that: 1. Galanin plays the role of an inhibitory neuromodulator of OT release from the neurohypophysis; its effect is opposite at the hypothalamic level. 2. Galanin acts as the stimulatory neuromodulator of OT release in response to prolonged osmotic stimulus; an acute osmotic stimulus blocks OT-ergic neurons susceptible to Gal. (Endokrynol Pol 2013; 64 (2): 139–148

Space Law and Space Mining, Exploring New Horizons Amid COVID-19 Pandemic

This study analyses the current scenario with COVID-19 affecting the international and Thai space law, and its impacts and corresponding repercussions upon the Thai economy, ASEAN region and then at international level. The methodology adopted for this study is a mixed method with qualitative research tools collected from key informant interviews and focus group discussions. The data analysis involves the Strength, Weakness, Opportunity, and Threat (SWOT) analysis, which has been integrated with Hierarchical Thematic areas to provide the supporting model for wholesome recommendations through analyzing the findings from the research. The key respondents involved several government officials associated with Thai space agencies and departments, along with judges, lawyers, researchers, academicians, non-government organizations (NGO) officials, and law students. The findings provided the need for adoption of Treaty leading to the creation of a space organization which would be accountable towards setting up a legal framework for commencement of space mining operations. The international space tribunal is to be created under this international space organization to resolve any disputes arising out of space mining. The overall implications of this research would lead to the sharing of the benefits of space mining with both developed and developing countries to enhance sustainable development for all mankind. Doi: 10.28991/ESJ-2023-SPER-09 Full Text: PD

Association between the ACE I/D polymorphism and physical activity in Polish women

Angiotensin converting enzyme gene (ACE) is the most frequently investigated genetic marker in the context of genetic conditioning of athletic predispositions. However, the knowledge of ACE\u2019s potential modifying effect on changes in selected body traits achieved through a training programme is still limited. Therefore, we have decided to check whether selected body mass, body composition variables, oxygen uptake parameters as well as strength/speed parameters observed in physically active participants will be modulated by the ACE I/D polymorphism. The genotype distribution was examined in a group of 201 young healthy women measured for chosen traits before and after the completion of a 12-week moderate-intensive aerobic training programme. Our results revealed the significant genotype 7 training interactions for VEmax and power of countermovement jump, whereas training improvements were demonstrated for almost all parameters. In addition, main effects of the ACE I/D genotype on TGL, HDL, glucose and 10 m run were observed. A significant increase in VEmax was demonstrated for II and DD genotypes, but not for ID heterozygotes. The greatest gain in power of countermovement jump was observed in II homozygotes, although DD and ID were associated with a significant increase as well. Our study indicated that the polymorphism was associated with changes in VEmax and power of countermovement jump in response to a 12-week aerobic training programme in Caucasian women. However, more experimental studies are needed to establish the ACE gene 7 physical activity interaction