Perception of pain as a result of orthodontic treatment with fixed appliances

The aims of this study were to investigate the intensity, location and duration of patients' discomfort following insertion of orthodontic appliances, and to examine for interactions between patient age, gender, appliance type and the perception of pain. After insertion of orthodontic appliances, 170 patients received eight questionnaires, one they completed and returned after 4 h, then one daily for 7 days. The respondents' ages ranged from 8-53 years (median age 13 years 7 months); 45 per cent were male and 55 per cent female. Of the patients, 65 per cent reported pain after 4 h and 95 per cent after 24 h. After 7 days, 25 per cent of the patients still reported discomfort. Patients' pain intensity scores were significantly higher for the anterior than for the posterior teeth. On day 1, 16 per cent took analgesics and 18 per cent reported being awakened the first night. Comparing a 2 × 4 appliance, a full appliance in one arch and in both arches, no statistical differences were found for reported pain frequency, general intensity of pain, pain at the teeth, discomfort when biting and chewing and analgesic consumption. The perception of general pain intensity, analgesic consumption, pain when eating and the influence of discomfort on daily life were all significantly greater in girls than in boys. Patients younger than 13 years reported pain significantly less frequently than the older patients. The highest frequency of pain was found in the group of 13-16 year olds. The pain intensity did not differ among the age group

Electronic structure study by means of X-ray spectroscopy and theoretical calculations of the "ferric star" single molecule magnet

The electronic structure of the single molecule magnet system M[Fe(L)2]3*4CHCl3 (M=Fe,Cr; L=CH3N(CH2CH2O)2) has been studied using X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, soft X-ray emission spectroscopy, and density functional calculations. There is good agreement between theoretical calculations and experimental data. The valence band mainly consists of three bands between 2 eV and 30 eV. Both theory and experiments show that the top of the valence band is dominated by the hybridization between Fe 3d and O 2p bands. From the shape of the Fe 2p spectra it is argued that Fe in the molecule is most likely in the 2+ charge state. Its neighboring atoms (O,N) exhibit a magnetic polarisation yielding effective spin S=5/2 per iron atom, giving a high spin state molecule with a total S=5 effective spin for the case of M = Fe.Comment: Fig.2 replaced as it will appear in J. Chem. Phy

Electron irradiation effects on superconductivity in PdTe2_2: an application of a generalized Anderson theorem

Low temperature ($\sim$ 20~K) electron irradiation with 2.5 MeV relativistic electrons was used to study the effect of controlled non-magnetic disorder on the normal and superconducting properties of the type-II Dirac semimetal PdTe$_2$. We report measurements of longitudinal and Hall resistivity, thermal conductivity and London penetration depth using tunnel-diode resonator technique for various irradiation doses. The normal state electrical resistivity follows Matthiessen rule with an increase of the residual resistivity at a rate of $\sim$0.77$\mu \Omega$cm/$(\textrm{C}/\textrm{cm}^2)$. London penetration depth and thermal conductivity results show that the superconducting state remains fully gapped. The superconducting transition temperature is suppressed at a non-zero rate that is about sixteen times slower than described by the Abrikosov-Gor'kov dependence, applicable to magnetic impurity scattering in isotropic, single-band $s$-wave superconductors. To gain information about the gap structure and symmetry of the pairing state, we perform a detailed analysis of these experimental results based on insight from a generalized Anderson theorem for multi-band superconductors. This imposes quantitative constraints on the gap anisotropies for each of the possible pairing candidate states. We conclude that the most likely pairing candidate is an unconventional $A_{1g}^{+-}$ state. While we cannot exclude the conventional $A_{1g}^{++}$ and the triplet $A_{1u}$, we demonstrate that these states require additional assumptions about the orbital structure of the disorder potential to be consistent with our experimental results, e.g., a ratio of inter- to intra-band scattering for the singlet state significantly larger than one. Due to the generality of our theoretical framework, we think that it will also be useful for irradiation studies in other spin-orbit-coupled multi-orbital systems.Comment: 22 pages, 12 figure

Sum-over-states vs quasiparticle pictures of coherent correlation spectroscopy of excitons in semiconductors; femtosecond analogues of multidimensional NMR

Two-dimensional correlation spectroscopy (2DCS) based on the nonlinear optical response of excitons to sequences of ultrafast pulses, has the potential to provide some unique insights into carrier dynamics in semiconductors. The most prominent feature of 2DCS, cross peaks, can best be understood using a sum-over-states picture involving the many-body eigenstates. However, the optical response of semiconductors is usually calculated by solving truncated equations of motion for dynamical variables, which result in a quasiparticle picture. In this work we derive Green's function expressions for the four wave mixing signals generated in various phase-matching directions and use them to establish the connection between the two pictures. The formal connection with Frenkel excitons (hard-core bosons) and vibrational excitons (soft-core bosons) is pointed out.Comment: Accepted to Phys. Rev.

Low energy measurement of the 7Be(p,gamma)8B cross section

We have measured the cross section of the 7Be(p,gamma)8B reaction for E_cm = 185.8 keV, 134.7 keV and 111.7 keV using a radioactive 7Be target (132 mCi). Single and coincidence spectra of beta^+ and alpha particles from 8B and 8Be^* decay, respectively, were measured using a large acceptance spectrometer. The zero energy S factor inferred from these data is 18.5 +/- 2.4 eV b and a weighted mean value of 18.8 +/- 1.7 eV b (theoretical uncertainty included) is deduced when combining this value with our previous results at higher energies.Comment: Accepted for publication in Phys. Rev. Let

Future orientation and planning in forestry: a comparison of forest managers' planning horizons in Germany and the Netherlands

Long range (or strategic) planning is an important tool for forest management to deal with the complex and unpredictable future. However, it is the ability to make meaningful predictions about the rapidly changing future that is questioned. What appears to be particularly neglected is the question of the length of time horizons and the limits (if any) to these horizons, despite being considered one of the most critical factors in strategic planning. As the future creation of values lies within individual responsibility, this research empirically explored the limits (if any) of individual foresters¿ time horizons. To draw comparisons between countries with different traditions in forest management planning, data were collected through telephone surveys of forest managers in the state/national forest services of the Netherlands and Germany. In order to minimize other cultural differences, the research in Germany concentrated on the federal state of Nordrhein-Westfalen, which has considerable similarities with the Netherlands, e.g. in topography, forest types and forest functions. The results show that, in practice, 15 years appears to be the most distant horizon that foresters can identify with. This is in sharp contrast to the time horizons spanning decades and even generations that are always said to exist in forestry. The ¿doctrine of the long run¿¿the faith in the capacity of foresters to overcome the barriers of the uncertain future and look ahead and plan for long-range goals¿which in many countries still underlies traditional forest management, can therefore be rejected

Are Courts Phoning It in? Resolving Problematic Reasoning in the Debate over Warrantless Searches of Cell Phones Incident to Arrest

In 1973, the United States Supreme Court in United States v. Robinson granted police broad authority to search arrestees’ personal property. Robinson’s broad rule has not been significantly limited and appears increasingly anachronistic in an age of rapidly advancing mobile technologies. Whether upholding or invalidating such searches, courts have relied on reasoning that ignores or conflicts with Robinson. This Article illustrates four problematic contrivances used by state and federal courts: (1) the comparison of mobile devices to “containers; (2) the misinterpretation of United States v. Chadwick’s concept of “property not immediately associated with the person;” (3) the unjustifiable application of Arizona v. Gant’s “reason to believe” rationale; and (4) the baseless categorical exclusion of cell phones from the search incident doctrine. In light of the public’s apparently high expectation of privacy for information stored on mobile devices, this Article recommends two possible solutions for restricting police authority: (1) return to an exigency-based rationale following Chimel v. California or (2) look to state legislatures to curb police powers through law making