How to observe dipolar effects in spinor Bose-Einstein condensates

We study a spinor condensate of alkali atoms in F = 1 hyperfine state under the presence of an oscillating magnetic field. We find resonances which, due to the dipolar interactions, magnify the transfer of atoms from mF = 1 to mF = 0 Zeeman sublevel. These resonances occur at magnetic fields of the order of milligaus and are broad enough to enable observation of the famous Einstein-de Haas effect, which is solely a dipolar effect, in systems of cold alkali gases.Comment: 4 pages, 3 figure

Coherence properties of spinor condensates at finite temperatures

We consider a spinor condensate of 87Rb atoms in its F=1 hyperfine state at finite temperatures. Putting initially all atoms in m_F=0 component we find that the system evolves into the state of thermal equilibrium. This state is approached in a step-like process and when established it manifests itself in distinguishable ways. The atoms in states m_F=+1 and m_F=-1 start to rotate in opposite directions breaking the chiral symmetry and showing highly regular spin textures. Also the coherence properties of the system changes dramatically. Depending on the strength of spin-changing collisions the system first enters the stage where the m_F=+1 and m_F=-1 spinor condensate components periodically loose and recover their mutual coherence whereas their thermal counterparts get completely dephased. For stronger spin changing collisions the system enters the regime where also the strong coherence between other components is built up.Comment: 5 pages, 4 figure

Alterations of High-Energy Brain Metabolites Across Multiple Neurodegenerative Disorders

Brain energy metabolism is vital for many cellular processes including homeostasis and thus disturbances to metabolism can be the cause or consequence of neurodegeneration. Metabolic discrepancies have been hypothesized to be involved but less frequently demonstrated to be manipulated by acute and chronic neurodegenerative disorders such as stroke, traumatic brain injury, and epilepsy. I hypothesized that cerebral energy levels are decreased in my model systems for Alzheimer\u27s disease, Autism, Down syndrome, and HIV-1 dementia and that dietary treatments could enhance energy reserves and protect against neurodegenerative disease. For rodent studies, I utlilized a high-energy head focused microwave irradiation system to kill animals but most importantly to snap-inactivate all cerebral enzymes, including those that contribute to the rapid degradation of high-energy phosphate compounds. I found that energy levels are diminished in a high-cholesterol diet model for Alzheimer\u27s disease in rabbit, a trisomic mouse model for Down syndrome (Ts65Dn), and following administration of Tat to primary mouse cortical cultures as a model for HIV-1 dementia. My experiments also examined the extent to which protection is provided by creatine supplementation and the ketogenic diet in models of HIV-1 dementia and epilepsy, respectively. Creatine bioenergetically protected against Tat-induced decreases in cellular levels of ATP, Tat-induced mitochondrial hypopolarization, and Tat-induced mitochondrial permeability transition pore opening. My calorie restricted ketogenic diet studies demonstrated this diet\u27s ability to protect against chemically induced seizures. As well, I observed a coordinated upregulation of all differentially regulated transcripts encoding energy metabolism enzymes, increased numbers of mitochondrial profiles, and ultimately augmented high-energy phosphate levels in seizure naïve rats. My studies demonstrate compromised brain energy levels in the aforementioned neurodegenerative disorders and that dietary treatments such as creatine supplementation for HIV-1 dementia and the ketogenic diet for epilepsy, may protect cerebral function by enhancing neuroenergetics

Case report : Williams-Campbell syndrome

Background: Williams-Campbell syndrome is a rare type of bronchiectasis that is due to deficiency or absence of cartilage in the fourth- to sixth-order bronchi. Case Report: The paper presents the case of a patient with large, bilateral bronchiectasis caused by defect of cartilage in the fourth- to sixth-order bronchi referred to as Williams-Campbell syndrome. Conclusions: Williams-Campbell syndrome should be taken into consideration in differential diagnosis of bronchiectasis. Both inspiratory and expiratory high-resolution computed tomography should be performed to establish the diagnosis

Resonant Einstein-de Haas effect in a rubidium condensate

We numerically investigate a condensate of $^{87}$Rb atoms in an F=1 hyperfine state confined in an optical dipole trap. Assuming the magnetic moments of all atoms are initially aligned along the magnetic field we observe, after the field's direction is reversed, a transfer of atoms to other Zeeman states. Such transfer is allowed by the dipolar interaction which couples the spin and the orbital degrees of freedom. Therefore, the atoms in $m_F=0,-1$ states acquire an orbital angular momentum and start to circulate around the center of the trap. This is a realization of the Einstein-de Haas effect in systems of cold gases. We find resonances which amplify this phenomenon making it observable even in very weak dipolar systems. The resonances occur when the Zeeman energy on transfer of atoms to $m_F=0$ state is fully converted to the rotational kinetic energy.Comment: 4 pages, 5 figure

Doping effects of Co, Ni, and Cu in FeTe0.65Se0.35 single crystals

The resistivity, magnetoresistance, and magnetic susceptibility are measured in single crystals of FeTe0.65Se0.35 with Cu, Ni, and Co substitutions for Fe. The crystals are grown by Bridgman's method. The resistivity measurements show that superconductivity disappears with the rate which correlates with the nominal valence of the impurity. From magnetoresistance we evaluate doping effect on the basic superconducting parameters, such as upper critical field and coherence length. We find indications that doping leads to two component superconducting behavior, possibly because of local charge depression around impurities.Comment: 4 pages, 4 figures, 1 table, Proceedings of the XV-th National School "Hundred Years of Superconductivity", Kazimierz Dolny, October 9-13, 201

Bialystok (Poland) - Green city. Historical Greenways in a Contemporary City

In contemporary theories of city design the issue of green corridors appears more and more frequently. They concern the development of greenways of communicative, ecological and recreational functions. Their purpose is to change the modern city landscape. Routes network dominant in the city space is to be replaced by ecological structures, improving the quality of life and introducing the green into the city. This issue is discussed by a number of research teams and relates to the cities of different scale. Conducted works tend to indicate the direction for transformation of the existing urban structures. This process is to be accomplished by adapting the existing space or formation of new - greenways. Specific solutions for individual cities which create their own green corridors are based on local conditions and include defined cultural values of the place. This attitude is presented by a team from Bialystok who searches for a new shape of the city in relation to the history. The authors in their works refer to the spatial composition formed in the eighteenth century on the initiative of Hetman Jan Klemens Branicki, in the valley of the Biała River, which became the nucleus of the city of Bialystok (Jan Klemens Branicki - lived from 1689 to 1771, he was one of the biggest Polish magnates in the eighteenth century, the owner of 12 towns, including Bialystok, 257 villages and 17 palaces (Dobroński, 2012). The spatial arrangement of Branicki’s premises during its founding was multi-elemental and the area equaled the size of a modern city. The individual elements of the composition (villages, architectural and natural objects) were connected by roads, which may be the prototype of today\u27s system of the town green corridors (Turecki, 1996). The essence of the presented works is an attempt to make the elements of eighteenth-century composition readable in the structure of the modern city (Il. 1), and the green corridors reproducing the old communication links can make the tool for its realization