Controllable quantum scars in semiconductor quantum dots

Quantum scars are enhancements of quantum probability density along classical periodic orbits. We study the recently discovered phenomenon of strong, perturbation-induced quantum scarring in the two-dimensional harmonic oscillator exposed to a homogeneous magnetic field. We demonstrate that both the geometry and the orientation of the scars are fully controllable with a magnetic field and a focused perturbative potential, respectively. These properties may open a path into an experimental scheme to manipulate electric currents in nanostructures fabricated in a two-dimensional electron gas.Comment: 5 pages, 4 figure

Relativistic theory of magnetic scattering of x rays: Application to ferromagnetic iron

We present a detailed description of a first-principles formalism for magnetic scattering of circularly polar- ized x rays from solids in the framework of the fully relativistic spin-polarized multiple-scattering theory. The scattering amplitudes are calculated using a standard time-dependent perturbation theory to second order in the electron-photon interaction vertex. Particular attention is paid to understanding the relative importance of the positive- and negative-energy solutions of the Dirac equation to the scattering amplitude. The advantage of the present theory as compared with other recent works on magnetic x-ray scattering is that, being fully relativistic, spin-orbit coupling and spin-polarization effects are treated on an equal footing. Second, the electron Green’s function expressed in terms of the path operators in the multiple-scattering theory allows us to include the contribution of the crystalline environment to the scattering amplitude. To illustrate the use of the method we have done calculations on the anomalous magnetic scattering at the K , L_II , and L_III absorption edges of ferromagnetic iron

Deconvolving Instrumental and Intrinsic Broadening in Excited State X-ray Spectroscopies

Intrinsic and experimental mechanisms frequently lead to broadening of spectral features in excited-state spectroscopies. For example, intrinsic broadening occurs in x-ray absorption spectroscopy (XAS) measurements of heavy elements where the core-hole lifetime is very short. On the other hand, nonresonant x-ray Raman scattering (XRS) and other energy loss measurements are more limited by instrumental resolution. Here, we demonstrate that the Richardson-Lucy (RL) iterative algorithm provides a robust method for deconvolving instrumental and intrinsic resolutions from typical XAS and XRS data. For the K-edge XAS of Ag, we find nearly complete removal of ~9.3 eV FWHM broadening from the combined effects of the short core-hole lifetime and instrumental resolution. We are also able to remove nearly all instrumental broadening in an XRS measurement of diamond, with the resulting improved spectrum comparing favorably with prior soft x-ray XAS measurements. We present a practical methodology for implementing the RL algorithm to these problems, emphasizing the importance of testing for stability of the deconvolution process against noise amplification, perturbations in the initial spectra, and uncertainties in the core-hole lifetime.Comment: 35 pages, 13 figure

Validirane RP-RP-HPLC i TLC metode za simultano određivanje tamsulozin hidroklorida i finasterida u istom dozirnom pripravku

Reversed phase high-performance liquid chromatography (RP-HPLC) and thin-layer chromatography (TLC) methods have been developed and validated for simultaneous estimation of tamsulosin hydrochloride and finasteride in bulk drug and in combined dosage forms. RP-HPLC separation was achieved on a Phenomenex C18 column using methanol/0.02 mol L-1 ammonium acetate buffer/triethylamine (79.9 + 20 + 0.1, V/V/V) (pH 9.2) as mobile phase. The TLC separation was achieved on an aluminium-backed layer of silica gel 60F254 using toluene/methanol/triethylamine (9 + 1.5 + 1, V/V/V) as eluent. Quantification was achieved with photodiode array (PDA) detection at 235 nm over the concentration range 0.5–16 and 150 µg mL1 with mean recovery of 99.8 ± 0.9 and 100.0 ± 0.8 % for tamsulosin hydrochloride and finasteride, respectively, by the RP-HPLC method. Quantification was achieved with UV detection at 270 nm over the concentration range 100–2000 ng per spot and 250–5000 ng per spot with mean recovery of 98.9 ± 0.9 and 99.6 ± 0.7 % for tamsulosin hydrochloride and finasteride, respectively, by the TLC method. Both methods are simple, precise, accurate and sensitive and are applicable to the simultaneous determination of tamsulosin hydrochloride and finasteride in bulk drug and in combined dosage forms.U radu su opisani razvoj i validacija inverzno fazne kromatografije visoke učinkovitosti (RP-HPLC) i tankoslojne kromatografije (TLC) za simultano određivanje tamsulozin hidroklorida i finasterida kao čistih supstancija i u kombiniranim tabletama. Za RP-HPLC odjeljivanje korištena je Phenomenex C18 kolona (250 mm, 4,6 mm, 5 µm) i metanol/0,02 mol L–1 pufer s amonijevim acetatom/trietilamin (79,9+20+0,1, V/V/V) (pH 9,2) kao pokretna faza, pri protoku 1 mL min-1. TLC odjeljivanje rađeno je na silikagelu 60F254 na aluminijskoj podlozi, koristeći toluen/metanol/trietilamin (9+1,5+1, V/V/V) kao eluens. Za detekciju u RP-HPLC metodi korištena je fotodioda (PDA) pri 235 nm te je provedena kvantitacija u koncentracijskom području 0,5–16 µg mL–1 i 1–50 µg mL–1, uz srednji analitički povrat od 99,8 ± 0,9 % za tamsulozin hidroklorid i 100,0 ± 0,8 % za finasterid. Za kvantitaciju u TLC metodi korištena je UV detekcija pri 270 nm u koncentracijskom području 100–2000 ng po točki za tamsulozin hidroklorid i 250–5000 ng po točki za finasterid, uz srednji analitički povrat od 98,9 ± 0,9, odnosno 99,6 ± 0,7 %. Obje metode su jednostavne, precizne, točne i osjetljive i mogu se primijeniti za simultano određivanje tamsulozin hidroklorida i finasterida kao čistih supstancija i u kombiniranim dozirnim oblicima

Electronic structure investigation of CoO by means of soft X-ray scattering

The electronic structure of CoO is studied by resonant inelastic soft X-ray scattering spectroscopy using photon energies across the Co 2p absorption edges. The different spectral contributions from the energy-loss structures are identified as Raman scattering due to d-d and charge-transfer excitations. For excitation energies close to the L3 resonance, the spectral features are dominated by quartet-quartet and quartet-doublet transitions of the 3d7 configuration. At excitation energies corresponding to the satellites in the Co 2p X-ray absorption spectrum of CoO, the emission features are instead dominated by charge-transfer transitions to the 3d8L-1 final state. The spectra are interpreted and discussed with the support of simulations within the single impurity Anderson model with full multiplet effects which are found to yield consistent spectral functions to the experimental data.Comment: 8 pages, 2 figures, 2 tables, http://link.aps.org/doi/10.1103/PhysRevB.65.20510

Relativistic Calculation of two-Electron one-Photon and Hypersatellite Transition Energies for 12≤Z≤3012\leq Z\leq30 Elements

Energies of two-electron one-photon transitions from initial double K-hole states were computed using the Dirac-Fock model. The transition energies of competing processes, the K$\alpha$ hypersatellites, were also computed. The results are compared to experiment and to other theoretical calculations.Comment: accepted versio

Kun tilaa on vähän:tutkielma pienten asuntojen muunneltavuuden ja monikäyttöisyyden lisäämisestä joustavan suunnittelun keinoin esteettömyysohjeita luovasti soveltaen

Tiivistelmä. Tutkin diplomityössäni rakenteilla olevia pieniä kerrostaloasuntoja ja niiden joustavuuden toteutumista. Tutkin aihetta esteettömyysmääräysten ja -ohjeiden luovan soveltamisen sekä joustavan asunnon suunnittelun keinojen ja tilallisten logiikoiden avulla. Diplomityöni jakautuu kahteen osioon, kirjalliseen teoriaosuuteen ja suunnitelmaosuuteen. Kirjallisessa teoriaosassa pohjustan tutkielmani rajaukseen johtaneen idean, joka liittyy tutkimusten sekä arkkitehtijulkaisujen kritiikkiin pienenevästä ja joustamattomasta uudisasuntotuotannosta. Teoriaosuudessa taustoitan syitä pienten asuntojen suunnittelun taustalla, sekä pohdin olemassa olevan uudisasuntokannan tulevaisuuden näkymiä kirjallisuuskatsauksen avulla. Työni rajautuu tutkimaan pieniä asuntoja esteettömyyden ja joustavuuden näkökulmista. Kirjallisessa osuudessa esittelen uudisasuntosuunnitteluun vaikuttavia esteettömyysmääräyksiä ja -ohjeita, sekä käsittelen omassa luvussa joustavuutta yleisesti ja sen roolia suomalaisessa asuntosuunnittelussa. Lukujen avulla pyrin ymmärtämään esteettömyysmääräysten ja -ohjeiden, sekä joustavuuden toteutumisen suhdetta pienten asuintilojen muodostumisessa ja alustamaan teoriapohjaa aiheista suunnitelmaosuutta varten. Työni suunnitelmaosuudessa tutkin rakenteilla olevien pienten kerrostaloasuntojen joustavuuden lisäämisen mahdollisuuksia tutkittuja joustavuuden keinoja ja logiikoita hyödyntämällä, sekä esteettömyysmääräyksiä ja -ohjeita luovasti soveltamalla. Suunnitelmaosuus jakautuu kolmeen osaan. Ensin analysoin kohdekohtaisesti viittä case-asuntoa pohjapiirustusten avulla laadullisin kriteerein. Tarkasteluaineistona olevat case-asuntopohjat valikoin kolmen suurimman rakennusliikkeen Tampereella rakenteilla olevista yksiö- ja kaksiopohjista. Analysoin pohjapiirustuksissa tilakohtaisia mitoitusperiaatteita ja asuntojen joustavuuden mahdollisuuksia. Toisessa ja kolmannessa osassa suunnitelmaosuutta esitän jokaisesta case-asuntopohjasta kaksi vaihtoehtoista pohjaratkaisua, joissa hyödynnän työni teoriaosuudessa esiteltyjä joustavan asunnon tilallisia logiikoita ja muunneltavia suunnitteluratkaisuja, sekä sovellan luovasti esteettömyysmääräyksiä ja -ohjeita. Case-pohjapiirustusten analyyseissä havaitsin, että ne vastasivat suurimmilta osin työni teoriaosuuden alussa kritisoituja, muodonannoltaan ja tilahierarkialtaan monotonisia kerrostaloasuntoja. Asuntopohjien tilajärjestyksestä oli tunnistettavissa esteettömyysmääräysten ja -ohjeiden ehdoin muodostetut ja standardoidut pienen asunnon tilaratkaisut, jotka ehdollistivat kapean tilan järjestäytymisen niiden mukaan. Pienten asuntojen tilaa hallitsi joustavan ja esteettömän käytön mahdollistava avotila, johon suurin osa asunnon toiminnoista sijoittui. Avotilan rajattu koko kuitenkin heikensi useissa case-pohjapiirustuksissa mahdollisuuksia hyödyntää tiloja vaihtelevin tavoin. Vaihtoehtoisten pohjapiirustusten suunnitelmista totesin, että pieniin asuntoihin voitiin luoda joustavuutta eri mittakaavoissa tiloja suhteellisten keveiden ja joustavuutta tuottavien suunnitteluratkaisujen avulla, sekä asuntojen tiloja kokonaan uudelleen järjestämällä. Vaikka pienissä ja haastavan muotoisissa vaihtoehtoisissa pohjapiirustuksissakaan ei synny kaiken kattavaa joustavuutta, vaihtoehtoisia tilaratkaisuja samaan asuntopohjaan esittämällä, asuntojen mitoitusta luovasti tarkastelemalla sekä erilaisia käyttömahdollisuuksia tarjoamalla voidaan lisätä asukkaiden vaikuttamismahdollisuuksia ja näin ollen mahdollisesti lisätä asuntojen houkuttelevuutta myös tulevaisuudessa. Esteettömyysmääräysten ja -ohjeiden luova soveltaminen jäi vaihtoehtoisissa pohjapiirustuksissa vähäiseksi. Määräysten ja -ohjeiden luovan soveltamisen sijaan asunnon esteettömiä tiloja ja toimintoja tulisi suunnitella asunnon muodon ehdoin yhdessä joustavuutta tuottavien suunnitteluratkaisujen kanssa

Effectiveness of a web-based treatment program using intensive therapeutic support for female patients with bulimia nervosa, binge eating disorder and eating disorders not otherwise specified: study protocol of a randomized controlled trial

Background: Disordered eating behavior and body dissatisfaction affect a large proportion of the Dutch population and account for severe psychological, physical and social morbidity. Yet, the threshold for seeking professional care is still high. In the Netherlands, only 7.5% of patients with bulimia nervosa and 33% of patients with anorexia nervosa are treated within the mental health care system. Easily accessible and low-threshold interventions, therefore, are needed urgently. The internet has great potential to offer such interventions. The aim of this study is to determine whether a web-based treatment program for patients with eating disorders can improve eating disorder psychopathology among female patients with bulimia nervosa, binge eating disorder and eating disorders not otherwise specified. Methods/design: This randomized controlled trial will compare the outcomes of an experimental treatment group to a waiting list control group. In the web-based treatment program, participants will communicate personally and asynchronously with their therapists exclusively via the internet. The first part of the program will focus on analyzing eating attitudes and behaviors. In the second part of the program participants will learn how to change their attitudes and behaviors. Participants assigned to the waiting list control group will receive no-reply email messages once every two weeks during the waiting period of 15 weeks, after which they can start the program. The primary outcome measure is an improvement in eating disorder psychopathology as determined by the Eating Disorder Examination Questionnaire. Secondary outcomes include improvements in body image, physical and mental health, body weight, self-esteem, quality of life, and social contacts. In addition, the participants’ motivation for treatment and their acceptability of the program and the therapeutic alliance will be measured. The study will follow the recommendations in the CONSORT statement relating to designing and reporting on RCTs. Discussion: This study protocol presents the design of a RCT for evaluating the effectiveness of a web-based treatment program using intensive therapeutic support for female patients with bulimia nervosa, binge eating disorder and eating disorders not otherwise specified

Faculty Perceptions of the Value of Academic Libraries: A Mixed Method Study

This article details the findings of a year-long study at Indiana University of Pennsylvania (IUP) Libraries which examined IUP faculty members’ perceptions of the value of library resources and services to both their research and teaching. Through a mixed-method study, which included an online survey and follow-up focus groups, the researchers found that faculty were dissatisfied with IUP Libraries’ marketing initiatives but satisfied with its small embedded librarian program. As a result, marketing and growth of the embedded librarian program became the two main focus areas for improvement in the next academic year