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The photoionization branching ratios of spin–orbit doublets are studied both experimentally and theoretically at energies several keV above threshold. The results show significant relativistic effects for Ar 2p in the autoionizing region below the 1s threshold, and large many-body effects for Xe 3d and 4d in the vicinity of the L-shell thresholds. The branching ratios in Xe are also found to vary significantly over very broad multi-keV energy regions both above and below the inner-shell thresholds. In addition, the Ar 2p study confirms experimentally the decades-old theoretical prediction that the nonresonant branching ratio does not approach the statistical (nonrelativistic) value, and, in fact, progressively diverges from statistical with increasing photon energy.

In the present scenario, the whole world struggling with COVID-19 which affects highly transmittable and pathogenic viral infection that rose by a newly discovered coronavirus and believed to be or...

Palmar midcarpal instability is an uncommon condition diagnosed clinically with a painful pathognomonic clunk on terminal ulnar deviation of the wrist. Various causes have been described, but congenital laxity of the carpal ligaments is thought to be a key contributor. Treatment commences with conservative measures. This includes proprioceptive training based on more recent concepts on the sensorimotor function of the wrist. When these measures plateau, surgery is considered. The lack of high-level evidence and consensus on its cause continue to hamper our understanding and knowledge of this condition. The purpose of this review is to examine the current evidence to conceptualize this mysterious, yet infrequent phenomenon, and to provide an algorithm on its management.

Data for the poster presented in the conferenceQuantum simulation and computation, Spain, 14-18/10/2019 https://zenodo.org/record/3733498#.XoSaAy-w3PA &nbsp

Single atoms or solid-state emitters are very promising candidates for building quantum network nodes as they provide for a spin-photon interface that also has quantum information processing capabilities. Among solid-state materials, rare earth ion-doped crystals constitute a promising platform for quantum information processing and networking. They feature exceptional spin coherence time to store information, narrow optical transitions to act as an interface to optical photons (including at telecom wavelength for erbium ions), and possibilities to realize quantum gates between single ion qubits. Coupling quantum emitters to optical cavities enables channelling the emission from the emitters into the cavity mode while decreasing their emission lifetime. This allows the realization of an efficient and high-rate spin-photon interface, while also increasing the indistinguishability of the emitted photons in the presence of dephasing. However, a reduction in the excited state lifetime also reduces the time available to realize quantum gates that rely on a dipole-blockade mechanism achieved by driving the emitter to the excited state. Dynamic control of the Purcell factor would hence enable decoupling the emitter from the cavity when performing gates, and coupling it back at a desired time to emit a single-photon with a tunable waveshape. In this work [1], by utilizing erbium-doped nanoparticles coupled to a fully tunable high-finesse fiber-based optical cryogenic microcavity, we demonstrate a Purcell factor of 31 that can be controlled on a timescale of 100 microseconds, which is more than 100 times faster than the spontaneous emission lifetime of the erbium ions. This is achieved by tuning the length of the cavity, and hence its resonance frequency, via a piezoelectric device with sub-nanometre precision. Additionally, we demonstrate that this technique can be operated with a bandwidth high enough to shape deterministically the spontaneous emission of the erbium ions. With some improvements, this technique has the potential to reach switching times of a few microseconds. Combined with single-ion addressing, this ability will enable the generation of fully tunable narrowband single photons at telecom wavelengths, and quantum processing using single rare-earth-ions. Our approach therefore opens the door to a solid-state quantum node with the potential of exhibiting quantum computing and communication capabilities all in a single device. [1] Bernardo Casabone, Chetan Deshmukh, Shuping Liu, Diana Serrano, Alban Ferrier, Thomas Hümmer, Philippe Goldner, David Hunger, and Hugues de Riedmatten, “Dynamic control of Purcell enhanced emission of erbium ions in nanoparticles”, arXiv:2001.08532 (2020)

Essentials Cancer patients receiving anticoagulants for venous thromboembolism have an elevated bleeding risk. This secondary analysis of CATCH assessed characteristics of clinically relevant bleeding (CRB). CRB occurs in 15% of cancer patients with thrombosis using therapeutic doses of anticoagulation. After multivariate analysis, risk factors for CRB were age >75 years and intracranial malignancy. Summary Background Cancer patients with acute venous thromboembolism (VTE) receiving anticoagulant treatment have an increased bleeding risk. Objectives We performed a prespecified secondary analysis of the randomized, open-label, Phase III CATCH trial (NCT01130025) to assess the rate and sites of and the risk factors for clinically relevant bleeding (CRB). Patients/Methods Patients with active cancer and acute, symptomatic VTE received either tinzaparin 175 IU kg-1 once daily or warfarin (target International Normalized Ratio [INR] of 2.0-3.0) for 6 months. Fisher's exact test was used to screen prespecified clinical risk factors; those identified as being significantly associated with an increased risk of CRB then underwent competing risk regression analysis of time to first CRB. Results Among 900 randomized patients, 138 (15.3%) had 180 CRB events. CRB occurred in 60 patients (81 events) in the tinzaparin group and in 78 patients (99 events) in the warfarin group (hazard ratio [HR] 0.64; 95% confidence interval [CI] 0.45-0.89). Common bleeding sites were gastrointestinal (36.7%; n = 66), genitourinary (22.8%; n = 41), and nasal (10.0%; n = 18). In multivariate analysis, the risk of CRB increased with age > 75 years (HR 1.83, 95% CI 1.14-2.94) and intracranial malignancy (HR 1.97, 95% CI 1.07-3.62). In the warfarin group, 40.4% of CRB events occurred in patients with with an INR of 75 years and intracranial malignancy.

The majority of orthopaedic screws are designed, tested and manufactured by existing orthopaedics companies and are predominantly developed with healthy bone in mind. The timescales and costs involved in the development of a new screw design, for example, for osteoporotic bone, are high. In this study, standard wood screws were used to analyse the concept of using three-dimensional printing, or rapid prototyping, as a viable stage of development in the design of a new bone screw. Six wood screws were reverse engineered and printed in polymeric material using stereolithography. Three of the designs were also printed in Ti6Al4V using direct metal laser sintering; however, these were not of sufficient quality to test further. Both the original metal screws (metal) and polymeric rapid prototyping screws were then tested using standard pull-out tests from low-density polyurethane blocks (Sawbones). Results showed the highest pull-out strengths for screws with the longest thread length and the smallest inner diameter. Of the six screw designs tested, five showed no more than a 17% variance between the metal and rapid prototyping results. A similar pattern of results was shown between the screw designs for both the metal and rapid prototyping screws in five of the six cases. While not producing fully comparable pull-out results to orthopaedic screws, the results from this study do provide evidence of the potential usefulness and cost-effectiveness of rapid prototyping in the early stages of design and testing of orthopaedic screws.

The photovoltaic (PV) system that is based on sub module-integrated converters (subMICs) is capable of maximizing solar energy harvest by eradicating power losses due to intrapanel mismatch. Modeling and simulation of subMIC-based systems are important to study the effect of PV partial shading, prove new control strategies, analyze distributed system dynamics, optimize system configurations, and determine system parameters, etc. However, the simulation of such systems can be very challenging due to the large number of switching-mode power units, nonlinear nature of PV generators, and complication of the coordinating control. This project provides an effective solution to simulate and control single-phase grid-tied PV systems that are based on a practical subMICs configuration by sliding mode control. The approach includes the simplified PV cell model and averaged model for power converters, which consider all dynamic interactions among the maximum power point tracking (MPPT). https://journalnx.com/journal-article/20150264

Microsatellite markers are useful in fingerprinting, for assessing variation within parental lines and testing the genetic purityof hybrid seed in rice. In this paper we report the identification of pure rice hybrids using microsatellite polymorphisms.Thirty simple sequence repeat microsatellite (SSR) markers were employed for fingerprinting 18 rice hybrids and theirparental lines. Twelve SSR markers were found polymorphic across the parents and produced unique fingerprint for theparents. Among the markers RM-17 and RM-84 precisely distinguished between pure hybrids and mixture/off type. Clusteranalysis based on Simple matching (SM) similarity coefficient using UPGMA grouped the hybrids into three clusters. Thegenetic similarity between the hybrids ranged from 0.43 to 0.81 with an average similarity index of 0.63.

A.S.K. acknowledges the support of the ARC Discovery grant DP120101805. V.K.D. acknowledges the support of the NSF under Grant No. PHY-1305085. P.C.D. acknowledges the support of a grant from the Department of Science and Technology, Government of India. S.T.M. was supported by the Division of Chemical Sciences, Basic Energy Science, Office of Science, US Department of Energy.

In this paper the temperature distribution is determined through a hollow cylinder under an arbitrary time dependent heat flux at the outer surface and zero heat flux at the internal boundary due to internal heat generation within it. To develop the analysis of the temperature field, we introduce the method of integral transform. The results are obtained in a series form in-terms of Bessel?s functions.

Time delay of photoemission from valence ns, np3/2, and np1/2 subshells of noble-gas atoms is theoretically scrutinized within the framework of the dipole relativistic random phase approximation. The focus is on the variation of time delay in the vicinity of the Cooper minima in photoionization of the outer subshells of neon, argon, krypton, and xenon, where the corresponding dipole matrix element changes its sign while passing through a node. It is revealed that the presence of the Cooper minimum in one photoionization channel has a strong effect on time delay in other channels. This is shown to be due to interchannel coupling. � 2014 American Physical Society.

The photoionization/photodetachment of atoms/ions of the Ar (Z = 18) isoelectronic sequence is investigated using three levels of calculation: the relativistic random phase approximation (RRPA) at various levels of truncation, RRPA with relaxation (RRPA-R) and the Tamm-Dancoff approximation (TD). The evolution of correlation and relaxation effects along the isoelectronic sequence members (Cl-, Ar, K+, Sc3+, Mn7+, Cu11+, Kr18+, Mo24+ and Cd30+) is investigated. � 2011 IOP Publishing Ltd.

The whole theoretical framework of physics rests only on a few but profound principles. Wigner enlightened us by elucidating that "It is now natural for us to try to derive the laws of nature and to test their validity by means of the laws of invariance, rather than to derive the laws of invariance from what we believe to be the laws of nature." Issues pertaining to symmetry, invariance principles and fundamental laws challenge the most gifted minds today. These topics require a deep and extensive understanding of both 'quantum mechanics' and the 'theory of relativity'. We attempt in this pedagogical article to present a heuristic understanding of these fascinating relationships based only on rather elementary considerations in classical and quantum mechanics. An introduction to some fundamental considerations regarding continuous symmetries, dynamical symmetries (Part 1), and discrete symmetries (Part 2) (parity, charge conjugation and time-reversal), and their applications in atomic, nuclear and particle physics, will be presented. � 2010 Indian Academy of Sciences.

This article is the second part of our review of the important role that symmetry plays in atomic and subatomic physics. We will concentrate on the discrete symmetries - parity, charge conjugation, and time reversal - that have played a significant part in the development of the 'standard model' of particle physics during the latter part of the 20th century. The importance of experimental tests of these symmetries, in both atomic and particle physics, and their sensitivity to new phenomena is also discussed. To conclude, we describe how 'symmetry breaking' in the standard model leads to the generation of mass via the Higgs mechanism and how the search for evidence of this symmetry violation is one of the principal goals of the Large Hadron Collider, which began operating at CERN, Switzerland in 2009. � 2010 Indian Academy of Sciences.

The dipole angular distribution asymmetry parameter, ?, for photoelectrons resulting from 2p photoionization of Ar, Ar6+, and Ar8+ and Ca, Ca2+, and Ca8+ of the Ar (Z=18) and Ca (Z=20) isonuclear sequences, respectively, have been studied using the relativistic random-phase approximation over a broad range of photon energy. In the absence of relaxation, it is known that inner-shell cross sections are essentially unchanged, as a function of photon energy, upon the removal of outer-shell electrons. The present results show that this is not true for the photoelectron angular distribution asymmetry parameters, particularly near the ionization thresholds. � 2010 The American Physical Society.

The effect of an endohedral confinement on the quadrupole photoionization of atomic Xe is studied using the relativistic random phase approximation (RRPA). The atom's confinement is modelled by placing atomic Xe at the centre of a C60 cage represented by an annular potential around it. A new confinement resonance is reported in the 4p quadrupole cross-section along with 'correlation confinement resonances' in 4d, 5s and 5p photoionizations at about 185 eV. The effect of the confinement on the non-dipole photoelectron angular distribution parameter ? is also reported. � 2009 IOP Publishing Ltd.

Stable silver nanoparticles were generated in aqueous medium by amine, hydroxy and carboxylate terminated poly(amidoamine) (PAMAM) dendrimers in the absence of conventional reducing agents and light irradiation. Mechanistic studies suggest that, in spite of their lower pKa values, tertiary amines present in the dendritic structures act as the reducing agent. Dynamic light scattering and electron microscopic studies reveal that PAMAM dendrimers aggregate in presence of silver ions and the aggregation propensity plays a pivotal role in altering the size and shape of the nanoparticles generated in the dendritic milieu. The formation of metal nanoparticles with uniform size and shape by amine terminated PAMAM dendrimer is attributed to the unique aggregation propensity of amine terminated PAMAM. �2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nondipole photodetachment parameters for the 3p subshell of Cl- are calculated using relativistic random-phase approximation (RRPA). Interchannel-coupling effects on nondipole photodetachment parameters for the 3p subshell are studied with different degrees of truncation of the RRPA. It is inferred from the present investigations that the shape resonance in the photodetachment cross-section profile and the positions of the Cooper minima are sensitive to interchannel coupling. An analysis of the angular distribution of the photoelectrons reveals how the Cooper minima in the dipole and the quadrupole channels introduce a complex energy dependence, with peaks and zeroes, of the nondipole asymmetry parameter ?. � 2009 The American Physical Society.

Calculations and measurements of the Xe 5s and 5p nondipole photoelectron asymmetry parameters are obtained, which present clear evidence of the existence of quadrupole Cooper minima, i.e., minima in quadrupole matrix elements as a function of energy, in the photoionization process. This verifies earlier predictions of quadrupole Cooper minima. � 2008 IOP Publishing Ltd.

Copper nanoclusters have been formed in fused silica glasses under 100�keV and 200�keV Cu + ion implantations. UV-Vis spectroscopy measurements have revealed prominent linear absorption bands at characteristic surface plasmon resonance (SPR) frequency signifying the appreciable formation of copper colloids in glass matrices even without thermal treatments. Ion-induced colloid formation in glasses without thermal treatments is probably the first time observation in the present study. Subsequent annealing of the implanted samples has resulted in the further enhancement of the absorption bands. Formation of copper nanoclusters without thermal annealing can be attributed to the relatively high mobility of copper atoms even at ambient conditions. The transmittance measurements made by Z-scan technique have revealed saturable absorption signifying the nonlinear optical responses of the metal nanocluster-glass composites. � 2007 Elsevier B.V. All rights reserved.

Zeeman splitting in the D2 line of rubidium atoms ( 87Rb and 85Rb) has been studied using 'Doppler broadened' as well as 'saturation absorption spectroscopy'. While a linearly polarized beam was used for the former experiment, in the latter case a (?, ?�) polarization configuration was employed for both pump and probe beams. Zeeman lines have been observed by applying a field up to 5 mT. The field variation of relative line intensities in Doppler-broadened spectrum was determined following Tremblay et al and Nakayama's four-level model. For the saturation spectrum, a four-level model was used. Because the enhancement of absorption at the field is as low as 1 mT, the Fg ? 2 to Fe ? 3 transition for 87Rb can be used as the reference for laser locking. Level crossing is observed in 85Rb at fields less than 5 mT. � 2007 IOP Publishing Ltd.

A theoretical study of dipole and quadrupole Cooper minima, along with dipole and nondipole photoelectron angular distribution parameters, in Hg 6s has been performed using the relativistic-random-phase approximation methodology. It is found that the Cooper minima affect the angular distribution parameters dramatically. In addition, the results show that the angular distribution parameters are extremely sensitive to both relativistic and correlation effects (interchannel coupling). � 2007 The American Physical Society.

A study of the combined effects of correlation, confinement and relativistic effects on the photoionization of the outer ns subshells of the alkaline-earth-metal atoms, Mg, Ca, Sr and Ba has been performed with particular emphasis on the Cooper minima using the relativistic-random-phase approximation (RRPA) methodology. It is found that the response of the Cooper minima to these various effects can be rather different behavior for the various atoms considered. On the other hand, relativistic effects were found to be essentially obliterated by confinement, in all cases. The situations are analyzed in detail and qualitative understanding of most of the phenomenology is presented. � 2007 The American Physical Society.

Accurate {\it ab initio} calculations have been carried out to study the valence electron removal energies and oscillator strengths of astrophysically important electromagnetic transitions of quadruply ionized vanadium, $V^{4+}$. Many important electron correlations are considered to all-orders using the relativistic coupled-cluster theory. Calculated ionization potentials and fine structure splittings are compared with the experimental values, wherever available. To our knowledge, oscillator strengths of electric dipole transitions are predicted for the first time for most of the transitions. The transitions span in the range of ultraviolet, visible and near infrared regions and are important for astrophysical observations., Submitted in Astrophysical J

The purpose of this study was to evaluate the changes in alignment during the course of treatment for extra-articular distal radius fracture and the relationship of initial and intermediate radiographs, with the final radiograph taken at fracture union. A cohort of 96 consecutive patients who were conservatively managed for extra-articular distal radius fracture in an 18-month period was undertaken. The radiographs analysed were taken at prereduction, postreduction, a week later and at fracture union. The radiological parameters analysed were radial tilt, radial length, radial inclination, dorsal comminution and ulnar styloid fracture. There was a significant change in radiographic alignment between initial and immediate postreduction radiographs, and between postreduction 1 week later radiographs (p 0.05). All patients with poor radiological outcome had ulnar styloid fractures. This was also associated with dorsal comminution in 86% of patients. Patients with satisfactory radiological outcome had ulnar styloid fracture and comminution in 34% and 43% of patients respectively. The final radiological outcome was not found to be influenced by initial unsatisfactory alignment of radial tilt, radial length and radial inclination individually or in combination. We suggest that two clinic visits after initial reduction of the fracture should be sufficient to manage such injuries; the first visit 1 week after manipulation to detect unacceptable displacement and if found satisfactory, the last visit at fracture union for final review, advice and referral to physiotherapy.

The aim of this study was to assess whether surgical decompression for carpal-tunnel syndrome (CTS) in the presence of primary or secondary osteoarthritis of the wrist is associated with poorer patient satisfaction. We did a retrospective matched cohort study. Twenty-four patients who underwent surgical decompression for CTS secondary to osteoarthritis were identified by reviewing the notes and the radiographs. A control group consisted of 24 patients without osteoarthritis of the wrist who underwent carpal-tunnel decompression. The control group was matched for age, sex, side, and neuro-physiological severity of the nerve compression. In the group with osteoarthritis of the wrist, 17 (71%) patients reported their symptom relief as satisfactory, and 7 (29%) reported the results as unsatisfactory. In the control group, 23 (96%) patients reported their symptom relief as satisfactory, and 1 (4%) reported the results as unsatisfactory (P=0.0325). In conclusion, patient satisfaction following surgical decompression in patients with secondary CTS due to osteoarthritis was significantly lower compared to patients without osteoarthritis of the wrist.

Interchannel coupling effects involving non-dipole matrix elements on photoelectron angular distribution have been recently found to be of significant importance even at energies not so high above ionization thresholds. Studies have been reported on the angular distribution of photoelectrons from some inert gas atoms: Ne, Ar, Kr and Xe. In the present work, we report further studies on atomic xenon, and also results on atomic mercury, using the relativistic random phase approximation. Also, we report the angular distribution asymmetry parameters with the inclusion of non-dipole terms for a confined atom; @ Ca is considered as a model system for this study. � 2005 Elsevier Ltd. All rights reserved.

A modified semiclassical exchange potential (MSCEP) has been used in the distorted wave Born approximation (DWBA) to calculate the triple differential cross section of Xe(4d) in the coplanar asymmetric geometry at intermediate energy. The scattered and ejected electron energies are fixed at 1000 eV and 100 eV, respectively. Calculations have been carried out for the ejected electron angles of 2� and 8�. Agreement between the present calculations and experiment is better compared to that of earlier calculations using the corrected form of the local exchange potential of Furness and McCarthy (1973 J. Phys. B: At. Mol. Opt. Phys. 6 2280). � 2006 IOP Publishing Ltd.

Properties of the plasma containing Cl2, HBr, and O2 species used for polysilicon etching change when the chamber wall is coated with organic polymer, causing the etch performance to drift. In this work, the plasma instability due to surface polymerization has been characterized through the comparison of free radical densities in an etch chamber coated with fluorocarbon polymer and other materials such as silicon oxide and anodized aluminum. The results of plasma diagnostics show that chlorine, bromine, and oxygen densities decrease after a polymer film is deposited onto the chamber wall. The root cause for the decrease in halogen radical densities has been attributed to the higher surface recombination rate of these free radicals on polymer surface, while the decrease in oxygen radical density is mainly caused by the consumption of oxygen in the cleaning of the polymer deposition. The impact of the plasma property change on etch performance has also been analyzed through etch rate and critical dimension (CD) evaluation. The lower free radical density in polymer-coated chamber generally lowers the etch rate and generates CD gain but the sensitivity of the process drift to the plasma property variation depends on process conditions. Approaches to reduce the effect of surface polymerization have been discussed.

Photoionization cross sections and asymmetry $(\ensuremath{\beta})$ parameters for Kr $3s,$ $3p,$ and $3d$ subshells have been measured and calculated in the 300--1300-eV photon energy range. Good agreement between experiment and theory is found for both cross-section branching ratios and $\ensuremath{\beta}$ parameters. Interchannel coupling among the channels arising from $3s,$ $3p,$ and $3d$ subshells is found to be necessary for quantitative accuracy of the theory. This shows that the interchannel coupling phenomenology far above threshold, found previously for outer shells of Ne and Ar, is also operative for inner atomic shells.

A new scale of electronegativity based on X-ray spectroscopic data was earlier presented by Mande and others for the elements3Li to54Xe. The present paper reports an extension of this scale carried out for most of the heavier elements lying between55Cs and92U. The present approach is based on the physical interpretation of electronegativity of an atom as the attractive electrostatic force it exerts at a distance equal to its covalent radius. To estimate this force, experimental spectroscopic data have been employed. The merits of such an approach have been pointed out recently by Mullay and may be of interest in the context of the intimate relation found between electronegativity and superconducting transition temperature. ? 1990 Indian Academy of Sciences.

We present a combined theoretical and experimental investigation of photoionization along the Ne isoelectronic sequence and show that the near-threshold behavior of the cross section for Si 41 differs radically from the nearby ions in the sequence. We demonstrate that the general nature of the underlying physics implies that dramatic changes in near-threshold behavior may be expected for many other ions. PACS numbers: 32.80.Fb, 32.80.Hd, 52.25.Qt The response of positive ions to ionizing radiation, the fundamental process of photoionization, is a dominant process in the universe. However, it is largely unexplored experimentally due to the difficulty of producing and maintaining appropriate densities of multiply charged ions, along with the requirement for high-flux sources in the extreme UV and x-ray ranges [1,2]. Photoionization is particularly attractive for theoretical interpretation due to (i) selectivity, owing to dipole selection rules, (ii) the fact that the photon disappears, thereby simplifying the final state, and (iii) the weak coupling between the photon and target electrons, allowing focus on the many-body aspects of the electron-electron interactions of the target ion [3‐ 5]. From a fundamental point of view, positive ions provide a “laboratory” to investigate the dynamic interplay between many-body electron-electron correlations, electron-nucleus interactions, and relativistic effects by looking along an ionic sequence. With increasing ionization, as the electron-nucleus interactions dominate, the photoionization behavior will tend towards hydrogenic; however, this trend towards simplicity is not at all monotonic, and very significant changes in the cross section behavior may occur for particular ions. In this Letter, we report the first combined theoretical and experimental investigation of photoionization along the Ne isoelectronic sequence and show that the near-threshold behavior of the cross section for Si 41 differs radically from the nearby ions in the sequence. We demonstrate that the general nature of the underlying physics implies that dramatic changes in near-threshold behavior may be