bluuebunny/crossref_metadata_2025 huggingface dataset:
Coupled Proton Tunneling Systems: Observation of Ultraslow Relaxation Phenomena
Authors: Trommsdorff H. Peter , Rambaud Christoph , Ramaz François , Vial Jean-Claude
Published: February 2023

Tunneling phenomena manifest itself essentially in two different ways. One is the displacement of particles across energy barriers without the need of thermal activation. This is a relaxation phenomenon and accounts for the occurrence of chemical reactions at 0 K and the evolution of glasses which continues at the lowest temperatures and leads to such observations as spectral diffusion. The other is the splitting of energy levels in a potential having several identical minima. This splitting lifts the degeneracy of states which describe the particle localized in one of the (isolated) wells. This tunneling splitting (also called tunneling matrix element) has its origin in the "transparency" of the energy barrier and measures the amplitude of the wavefunction in the classically forbidden regions of the potential.
Theoretical Study of Hole Burning and Spectral Diffusion in Glasses
Authors: Silbey Robert
Published: February 2023

A microscopic model of a chromophore embedded in a glassy matrix, and interacting with phonons and two level systems (TLS) will be presented. The hamiltonian contains a a thermal (quantum) bath of phonons, chromophore (with a vibrational mode) interacting with phonons, and two level systems interacting with phonons. By a transformation of this hamiltonian, the linear chromophore-phonon and TLS-phonon interactions can be removed, leading to a new hamiltonian with TLS-chromophore interactions, TLS-TLS interactions, and residual phonon-TLS coupling. These terms produce TLS flips and dephasing and are often used as the starting point for spectral diffusion models of dynamics.
Bacteriorhodopsin - Optical Processor Molecules from Nature
Authors: Bräuchle C.
Published: February 2023

The field of molecular electronics is characterized by an attempt to
engineer and use devices on a molecular level. Supramolecular
chemistry is one way to produce such molecular devices. However, long
before supramolecular chemists tried to synthesize highly organized
artificial systems often employing principles of living nature, nature
itself has produced and optimized biological systems on a molecular
device level during a long period of evolution.
Size Dependent Spectroscopy of CdSe Nanocrystallites
Authors: Bawendi Moungi G.
Published: February 2023

Semiconductor crystallites which are 10's of Angstroms show a striking evolution of electronic properties with size.1 These particles (quantum dots) are large enough to exhibit a crystalline core, but small enough that solid state electronic and vibrational band structure is not yet developed. We use a recently developed synthetic method for the synthesis of high quality nanometer size (1-10 nm) II-VI semiconductor crystallites with narrow size distributions (σ <5%), emphasizing CdSe.2 Optical characterization of their electronic structure using pump-probe techniques, luminescence, and DC Stark techniques reveals both molecular and bulk-like characteristics as well as properties which are unique to nanometer size crystallites. We observe a number of discrete electronic transitions, assign them as coming from the creation of delocalized "particle-in-a-sphere" states using the theory of Ref. 3, and study their dependence on crystallite diameter.4 The Stark experiments are also compatible with the absorbing states as delocalized symmetric states. We use time resolved fluoresence line narrowing spectroscopy to study the dynamics of electron-hole recombination. We observe significant changes in electron-LO phonon coupling with time, temperature, and crystallite size and suggest that the electron-hole pair dynamics following photoexcitation are dominated by surface effects which are especially important in the smaller crystallites where a large fraction of the atoms are "surface" atoms.5
Using Photochemical Hole Burning to Map Local Electric Fields
Authors: Fleischer Everly B. , Kohler Bryan E. , Woehl Jörg C.
Published: February 2023

Octatetraene can be photoisomerized even when it is incorporated in a low temperature n-hexane crystal. When this is done by irradiating the zero phonon component of the S0→S1 origin band with a single frequency laser, very narrow (less than 10 MHz) persistent holes can be burned. We have used this increase in resolution to study the effect of an external electric field on the S0→S1 excitation energy: typical results are shown in Figure 1.
Photon Scanning Tunneling Microscope
Authors: Ohtsu Motoichi
Published: February 2023

A photon scanning tunneling microscope (PSTM) is an optical microscope with super-resolution beyond the diffraction-limit based on the near field optics, which has been intensively studied in these years[1]. Since it can be used not only as a microscope but also as a nanometric fabrication tool and a manipulator of nanometric particles, a variety of applications have been proposed[2]. This paper reviews the recent progress of our study on PSTM.
Near-field Time-Resolved Fluorescence Spectroscopy of Single Molecules
Authors: Xie X. Sunney , Dunn Robert C.
Published: February 2023

Fluorescence lifetime measurements on single dye molecules with nanometer spatial resolution are achieved by incorporating time-correlated single photon counting with a near-field fluorescence microscope.
Coherent Transient Continuous Optical Processing in a Solid
Authors: Zhu Miao , Jefferson C. Michael , Babbitt Wm. Randall
Published: February 2023

When a sequence of temporally modulated optical waveforms illuminate an inhomogeneously broadened absorbing medium, the resultant optical coherent transient output signal's represents the cross-correlation or convolution of the input temporal waveforms.1 The projected performance characteristics of coherent transient processors include data rates greater than 10 GHz, time-bandwidth products far in excess of 10,000, and the ability to fully process both amplitude and phase modulated waveforms.1,2 Previously it was assumed that the input data stream and pattern stream must both be shorter than the absorbing transition's homogeneous dephasing time and must both be reentered in order to process longer or multiple data streams.1 It has recently been proposed that patterns could be permanently stored in an inhomogeneously broadened solid and that input data streams of indefinite length could be continuously processed in real time without the need to reenter the input pattern.3,4 In this paper, we present a proof of concept demonstration of an optical coherent transient continuous correlator.
Long-Lived Stimulated Photon Echo Studies of Protein and Glass Dynamics
Authors: Leeson D. Thorn , Wiersma D. A.
Published: February 2023

The dynamical behavior of proteins is often interpreted in terms of conformational substates.1 A protein can assume a large number of slightly different structures, separated by conformational barriers. This view is very similar to the description of glass dynamics in terms of two-level systems.2,3 A two-level system (TLS) represents a group of atoms or molecules which can reside in either of two potential energy wells along a conformational coordinate. At very low temperature the TLS can fluctuate between the two potential energy minima through a tunneling process.
Studies on Photochemical Hole Burning in Japan
Authors: Tani Toshiro
Published: February 2023

Research activities on materials for photochemical hole-burning in Japan will be reviewed. Much stress is placed on those performed under the AIST project for eight years from 1985 to 1992FY.
Effects of Matrix Correlations on Inhomogeneous Spectral Distributions: Rare Gas and Polymeric Systems
Authors: Kador L. , Geissinger P. , Haarer D.
Published: February 2023

Inhomogeneous distributions of spectral lines are a ubiquitous phenomenon in nature. In the optical spectroscopy of dye molecules embedded in transparent solids, the inhomogeneous widths are usually much larger than the corresponding homogeneous linewidths of single molecules.
Photon-Gated Spectral Hole Burning in Mixed Meso-Phenyl-Tetrabenzoporphyrinato-Zinc/Aromatic Cyanide System and the Hole Filling Induced by Gating Beam
Authors: Wang Duo Yuan , Hu Ling Zhi , Hu Min Xue , He Hui Zhu , Zhao Li Zeng , Lu Zhen Zhong , Nie Yu Xin
Published: February 2023

Photon-gated organic materials have been received great attention in the frequency domain optical storage, because of the high photoresponsive ability, the convenience of preparating film and controllable composition of materials. However, the dependence of the frequency for hole burning efficiency[1] and the hole width to be broadened accomponying with rising working temperature for hole burning[2] set up a limitation for the optical storage density.
Hole-Burning of Rare Earth Ions with kHz Resolution
Authors: Manson Neil B. , Sellars Matthew J. , Fisk Peter T.H. , Meltzer Richard S.
Published: February 2023

4fn ⇒ 4fn transitions of trivalent rare earth ions doped in crystals frequently give sharp spectral lines. The transitions associated with the higher levels of a multiplet can be relatively sharp, 10-1000 GHz, where the width is determined by the decay rate of the levels by spontaneous phonon emission to lower levels. The transitions and their linewidth can be determined using conventional absorption or excitation techniques. On the other hand the transitions associated with the meta-stable lower levels typically give much sharper features with linewidths of 1 - 100 GHz and the widths are determined by the inhomogeneities of the crystal field. These inhomogeneous linewdths can be obtained by conventional spectroscopic techniques but the homogeneous linewidth requires more innovative techniques such as optical holeburning or photon echoes. The time domain photon echo measurements do not requiring a high resolution source and have frequently been used to establish that the homogeneous linewidth of such transitions. The lines can be very narrow down to the kHz regime [1,2]. Should complimentary measurements be attempted in the frequency domain utilising holeburning a special frequency stabilised lasers is required and one has been developed in association with the current work [3].
Spectral Hole-Burning in Photosynthetic Pigment-Protein Complexes: Size-Dependent Dynamics
Authors: De Caro C. , Creemers T.H.M. , Visschers R.W. , van Grondelle R. , Völker S.
Published: February 2023

The initial step in the photosynthetic process is the absorption of light by chlorophyll-type molecules bound to proteins in so-called light-harvesting (LH) complexes, and the subsequent transfer of the excitation energy among these antennae until it is trapped by the reaction center (RC). This entire process occurs in less than 100 ps. In the RC an electron is then transferred across the biological membrane, by which an electrochemical potential gradient is generated and the energy stored for subsequent processes.
Electron Transfer Reaction from Zinc(II)tetraphenylporphine to Dichloromethane
Authors: Kishii Noriyuki , Shirai Katsuya , Tamura Shin-ichiro , Seto Jun'etsu , Tokumaru Katsumi , Takagi Satohiro , Arai Tatsuo , Sakuragi Hirochika
Published: February 2023

Persistent spectral hole burning (PHB) offers the potential of ultra high density optical data storage1). Recently much effort has been directed towards photon-gated PHB material systems, since the systems have good properties for optical memories such as non-destructive reading and fast reaction time2). Thus it is important to study the reaction mechanism of photon-gated material systems not only to develop suitable material systems for optical memories but also to find new photochemical reactions at cryogenic temperatures.
Room-Temperature Persistent Spectral Hole Burning of Sm2+ in Disordered Fluorite-Type Single Crystals α-MALnF6 (M=Ca, Sr;A=Na, K, Rb;Ln=Y, La, Gd)
Authors: Kodama N. , Hara S. , Inoue Y. , Seita T. , Hirao K.
Published: February 2023

Persistent spectral hole burning (PSHB) is expected to be a mechanism for future ultrahigh density multi-wavelength optical memory whose density can be higher than the conventional optical memory by 10 to 104 times. PSHB optical memories are mainly studied for dye-doped polymers, but the hole burning temperatures for such poleymers are limited to tempertures lower than 140 K [1], Recently room-temperature PSHB has been observed in Sm2+ doped halide crystals [2-4] and glasses [5], and borate glasses [6]. The halide crystals are not bulk single crystals but polycrystals.
Thermally Induced Hole-filling Process In Donor-acceptor Electron Transfer System
Authors: Tian Mingzhen , Chang Tiejun , Zhang Jiahua , Luo Baozhu , Huang Shihua , Yu Jiaqi
Published: February 2023

Photon-gated spectral hole-burning in the organic donor-acceptor electron transfer system has attracted extensively interests because of its application background in frequency-domain optical storage. Several materials have been investigated from the aspects in hole-burning process[1–3], such as photon-gating effect, temperature dependence of hole width and hole-burning efficiency. A few works on hole-filling processes have been done[4], however, the filling mechanisms are not clear now.
Multiple Photon-Gated Persistent Spectral Holes Burnt over A Whole Absorption Band in A New System of Frequency-Domain Optical Storage Material
Authors: Zhao Youyuan , Pan Yongle , Yin Yu , Chen Lingbing , Wang Ruisheng , Li Fuming , Yao Shaoming , Zhang Manhua
Published: February 2023

Persistent spectral hole burning(PSHB) permits use of the frequency domain for achieving ultrahigh-density optical information storage in which the presence of a spectral hole at a particular laser frequency utilized to encode much many bits within a single focused laser spot. The ultimate storage density of the three-dimensional(x,y,f) optical memories can be increased to 109-1011 bits/cm2[1].
Accumulated Photon Echo Spectroscopy of Ordered (CaF2) and Disordered (CaF2-YF3) crystals with Nd3+ ions
Authors: Steeg K.W. Ver , Reeves R.J. , Fedorov V.V. , Karasik A. Ya. , Basiev T. T. , Powell R.C.
Published: February 2023

Numerous experimental investigations of homogeneous line broadening (Γh) of RE3+ ions in crystals and glasses in frequency and time domain [1] have shown that Γh for glasses exceed those for crystals by more than one order of magnitude at low temperatures (T) for the same ions and transitions. Discrepancies between theory and experimental results make it difficult to determine an influence of host disordering on the Γh in a wide temperature range. In this work we measured and compared Γh, values for ordered CaF2 and disordered CaF2-YF3 crystals doped with Nd3+ ions.
Local Dynamics in Solid Matrices Investigated by Malachite Green Optical Microprobes
Authors: Abedin Kazi Monowar , Yong Ye Jing , Inouye Hideyuki , Hattori Toshiaki , Nakatsuka Hiroki
Published: February 2023

Dynamics of molecules or molecular constituents doped in amorphous systems is recently of considerable interest. In these systems, it is important to know how rigidly the doped molecules (guest) are bound to the surrounding polymer matrix. The nature of the guest-matrix interaction, on which this rigidity depends, is not so well understood at present. The motion of the doped molecules or their constituents is influenced by the surrounding matrix. Molecular motions having no appreciable internal potential barrier, are ideal probes of matrix rigidity, since matrix friction or viscosity is the only impediment to the motion of molecules or molecular constituents in these cases.
The Change in Refractive Index and the Formation of Birefringence during Photoisomerization of Photochromic Dyes
Authors: Morino Shin'ya , Horie Kazuyuki , Yamashita Takashi
Published: February 2023

The optical switching devices in optical computing systems usually use electro-, acousto- optic and nonlinear optical effects. Photochemical reactions can be potentially used as one of the principles for photo-optical switching devices, because they change the electric structure of the system.1 In this study, the change in refractive indices of PMMA films containing DAAB (p- dimethylaminoazobenzene) during photoisomerization and the birefringence during polarized-light induced photoisomerization were measured, and the possibility as a photo-optical controlling material was examined.
Effect of laser irradiation on reflectivity of phase-conjugate signal from semiconductor nanoparticles
Authors: Fukumi Toshio , Nakao Kimiko , Sakaguchi Toru , Ohta Koji , Miya Masaru
Published: February 2023

Effect of laser irradiation on the reflectivity of phase-conjugate signal from semiconductor nanoparticles was examined. Experimental setup employed in the present study is illustrated in Fig.(1).
Theoretical Models for Photochromic Systems
Authors: Canel E.
Published: February 2023

Photo induced spectral changes of some molecules containing electronic π systems are investigated and the effect of electrocyclic reactions (ring closure etc) on their electronic structure is considered. Two types of molecules are studied

1) Molecules which exhibit two stable states characterized by different π electron configurations1) such as

2) electron transfer systems containing a "π electron bridge" linking donor and acceptor which can be modified by a photo induced reaction for example

Static electronic π systems are described by a nearest neighbor Huckel Theory, i.e. by a Hamiltonian of the type

where ai+, ai are the usual Fermion creation and destruction operators, ε the p electron energy and Γij the coupling between nearest neighbor p orbitals. Due to rotation of molecular fragments Γij depends on the orientation of the relevant p orbitals.
Analysis of the Importance of Matrix Correlations through Hole-Burning Experiments in Dye-Doped Rare Gas Matrices
Authors: Geissinger P. , Kador L. , Giering Th. , Haarer D.
Published: February 2023

Stochastic models to describe the inhomogeneous broadening of electronic transitions of dye molecules in amorphous hosts [1] and to account for the effects of external hydrostatic pressure on spectral holes [2] have been applied to analyze experimental results obtained in a variety of samples, with hosts ranging from polymers to aerogels. With these models it was possible to determine the compressibilities of various polymers by purely optical experiments. It is interesting that these results are in agreement with mechanically obtained data within approx. 15%. Furthermore, the depth ϵ of the assumed Lennard-Jones dye-matrix interaction potential could be calculated.
Observation of confined acoustic phonons in semiconductor nanocrystals by means of the persistent spectral hole-burning spectroscopy
Authors: Okamoto Shinji , Masumoto Yasuaki
Published: February 2023

Recently, semiconductor nanometer-sized microcrystallites (nanocrystals) are attracting much interest, because their optical properties are much different from bulk crystals. Their distinct optical properties are caused by three-dimensional confinement of phonons as well as electrons, holes and excitons in small volumes. The interaction between the confined electrons and phonons is an important factor that determines the optical properties.
Hole-burning in proton conducting oxide SrZrO3: Pr3+
Authors: Matsuo S. , Yugami H. , Ishigame M. , Shin S.
Published: February 2023

Long-lived or persistent spectral hole-burning has been observed in many rare-earth doped glasses and crystals [1]. In Eu3+ doped solids, hole-burning due to optical pumping of nuclear quadrupole levels has been observed. In Pr3+ doped solids, local ion rearrangement around Pr3+ often causes hole-burning. Macfarlane and co-workers have reported persistent spectral hole-burning in SrF2: Pr3+ and CaF2: Pr3+ [2, 3]. They have concluded that the light-induced D− ion motion causes the hole burning. In contrast with organic materials, such proton related hole-burning has not been reported so much in inorganic solids.
Spectral Hole Burning and Fluorescence Line Narrowing of Si Center in CVD Diamond
Authors: Gorokhovsky A.A. , Turukhin A. , Alfano R.R. , Phillips W.
Published: February 2023

In this presentation we report on several spectral features associated with Si impurity in diamond related to spectral hole-burning. Diamond, with its hardness and high temperature stability, is a potentially useful material for high temperature hole-burning storage. The first hole-burning in bulk diamonds [1] was observed from color centers in the spectra of N3 at 415 nm, H4 at 496 nm, N-V at 637 nm, and GR1 at 741 nm. Recently, hole-burning was observed for color centers N-V at 637 nm and 574 nm of electron irradiated chemical-vapor deposited (CVD) diamonds [2].
Rotational Rydberg states in polar molecules
Authors: Chernov V.E. , Dorofeev D.L. , Zon B.A.
Published: February 2023

The molecular Rydberg states have more complicated structure than the atomic ones. The phenomenon is due to the rotational spectrum being characteristic of molecules unlike atoms. Inasmuch as the distance between rotational levels of the molecular core is comparable to the distance between high excited levels in the pure Coulomb field, rotational states mix with Rydberg ones and form rotational-Rydberg (ro-Ry) states.
Programmable pulse delays by phase controlled frequency swept cw holograms
Authors: Altner Stefan , Bernet Stefan , Maniloff Eric , Graf Felix , Renn Alois , Wild Urs P.
Published: February 2023

The spectroscopic technique of photon echoes has been proven to be a versatile tool to obtain information about dephasing times and related parameters of materials [1]. In addition, applications within the framework of time domain optical data storage and processing have been discussed [2].
Generation of a Single-Lobe Radiation Pattern from a Phased-Array Laser Using a Near Contact Variable-Phase-Shift Zone Plate
Authors: Thaniyavarn Suwat , Dougherty William
Published: February 2023

Phased-locked semiconductor laser arrays have been a subject of great interest in recent years.(1-2) These laser arrays are very promising candidates as efficient high power monochromatic optical sources. The relative phases of the lasing elements of the array are locked to each other due to the effect of optical coupling between adjacent laser stripes, creating a stable far field radiation pattern. However, most of the phased array lasers reported previously showed double-lobe far-field patterns, which are undesirable for many applications.
Dependence of Diode Laser Linewidth on Facet Reflectivity and Output Power
Authors: Walther F. G. , Welford D.
Published: February 2023

In earlier work,1 it was demonstrated that diode laser frequency noise consists primarily of 1/f and spectrally white components, which cross typically between 0.1 and 1 MHz, depending on power level. The model is good out to a few hundred MHz, beyond which the noise spectrum increases to the relaxation oscillation and then decreases at higher frequencies. The white fm noise component alone produces a Lorentzian lineshape while the 1/f component alone leads to a Gaussian lineshape given reasonable limits on observation time. The total linewidth (fwhm), Δυ, results from the convolution of the Lorentzian, ΔυL, and Gaussian, Δυg, components; the relationship among the components has been approximated empirically by.
Low Threshold Current Density 2.2 µm GaInAsSb/AℓGaAsSb Double Heterostructure Lasers
Authors: Caneau C. , Zyskind J. L. , Dentai A. G. , Glover T. E. , Sulhoff J. W. , Srivastavaf A. K. , Pollack M. A.
Published: February 2023

We earlier reported room temperature pulsed operation of
Ga0.84In0.16As0.15Sb0.85/AℓxcGa1−xcAs0.04Sb0.96 double heterostructure injection lasers (Fig. 1a) with an emission wavelength of 2.2 µm.1,2,3 The wafers were grown by liquid phase epitaxy (LPE) at ~ 530 °C, and their broad area threshold current densities, depend on xc, the Aℓ content of the confinement layers, and on the active layer thickness dact (see Figure 2). For xc = 0.27 (DH-I) the lowest threshold, Jth = 7 kA/cm2, is obtained with an active layer thickness dact = 0.8–1 µm. The best result for xc = 0.34 (DH-II) is Jth = 3.5 kA/cm2 and occurs for dact = 0.5–0.6 µm. The large values of the optimal active layer thickness suggest that there might be less optical confinement in these lasers than in GaInAsP/InP lasers. Estimates of the radiation confinement factor, using calculated values4,5 of the refractive indices for the active and confinement materials, nact and nconf, support this hypothesis. The confinement is weak because of the small index difference. It is improved and the optimal active layer thickness reduced when nconf is lowered, which occurs when xc is increased. However further increase of xc does not result in lower thresholds: two DH-III type wafers (xc = 0.4) gave thresholds of 3.7 and 8 kA/cm2, respectively. This we attribute to too high a lattice mismatch of the confinement layers with respect to the active layer and the substrate, resulting from the difficulty of incorporating enough As into the AℓGaAsSb layer to make it lattice-matched to GaSb.
"High-speed buried-heterostrueture InGaAsP/InP diode lasers"
Authors: Imai Hajime
Published: February 2023

InGaAsP/InP diode lasers emitting at 1.3 and 1.55 µm wavelengths are practically used in long-haul and high-bit rate transmission systems. Buried hetrostructure (BH) is important structure owing to the low threshold and the fundamental transverse mode lasing. Recently high-bit rate systems with more than 1 Gb/s are proposed and field trials have already been performed. For the purpose to obtain high-bit rate operation in BH diode lasers, there are two dominant factors that must be satisfied; one is the reduction of the parasitic capacitance and another is the increase in the relaxation oscillation frequency. In the following, I review them.
High speed 1.3µm InGaAsP Buried Crescent Injection Lasers With Semi-Insulating Current Confinement Layer
Authors: Cheng W. H. , Su C. B. , Buehring K. D. , Chien C. P. , Ure J. W. , Perrachione D. , Renner D. , Hess K. L. , Zehr S. W.
Published: February 2023

A hybrid growth technique has been used to fabricate high modulation bandwidth 1.3 µm InGaAsP buried crescent (BC) injection lasers. The technique involves a first growth of an Fe-doped semi-insulating (SI) InP current confinement layer by low pressure metal organic chemical vapor deposition (LPMOCVD) followed by a liquid phase epitaxy (LPE) regrowth. The lasers have room temperature threshold currents and differential quantum efficiencies ranging from 20 to 30 mA and 0.2 to 0.3 mW/mA/facet, respectively. A 3-dB modulation bandwidth of 5 GHz has been achieved.
High Power 1.3 Micron Laser Diodes
Authors: Rezek E.A. , Adachi N. , Tran D. , Yow L.
Published: February 2023

1.3 micron double channel planar buried heterostructure laser diodes have been fabricated which operate up to 110 mW CW. High power accelerated aging data is presented.
High temperature-stability of visible semiconductor lasers coupled with a short external cavity
Authors: Kawanishi Hidenori , Hayashi Hiroshi , Yamamoto Osamu , Miyauchi Nobuyuki , Maei Shigeki , Yamamoto Saburo , Hijikata Toshiki
Published: February 2023

Semiconductor lasers have been widely used for coherent light sources of various application systems. But the lasing wavelength hops from one longitudinal mode to another as the temperature changes. So applications are restricted for those which require precise control of their wavelength, for example high resolution spectroscopy. In order to obtain the temperature stability, we have developed new-type composite-cavity semiconductor lasers which are very simple to fabricate.
Modified Channeled Substrate Planar(CSP) Lasers with Lateral Leaky Mode Behavior
Authors: Lee Song J. , Figueroa Luis
Published: February 2023

The channeled-substrate-planar structure(CSP) was the one of the first semiconductor lasers which provided the lateral mode stabilization[l] and more recently has served as a prototype design for high power semiconductor lasers[2].
Beliefs, attitudes and practices towards scabies in central Ghana
Authors: Amoako Yaw Ampem , van Rietschoten Lotte Suzanne , Oppong Michael Ntiamoah , Amoako Kwabena Oppong , Abass Kabiru Mohammed , Anim Bernard Akoto , Laryea Dennis Odai , Phillips Richard Odame , Stienstra Ymkje
Published: February 2023

Background

Scabies commonly affects poor populations in low-middle-income countries. The WHO has advocated for country-driven and country-owned control strategies. Knowledge of context specific issues will be important for design and implementation of scabies control interventions. We aimed to assess beliefs, attitudes and practices towards scabies in central Ghana.

Methodology/Principal findings

Data was collected via semi-structured questionnaires for people who had active scabies or scabies in the past year and people who never had scabies in the past. The questionnaire covered several domains: knowledge about the causes and risk factors; perceptions towards stigmatisation and consequences of scabies in daily life; and treatment practices. Out of 128 participants, 67 were in the (former) scabies group and had a mean age of 32.3 ± 15.6 years. Overall scabies group participants less often indicated a factor to predispose to scabies than community controls; only ‘family/friends contacts’ was more often mentioned in the scabies group. Scabies causation was attributed to poor hygiene, traditional beliefs, heredity and drinking water. Individuals with scabies delay care seeking (median time from symptom onset to visiting the health centre was 21 [14 – 30] days) and this delay is enhanced by their beliefs (like witchcraft and curses) and a perception of limited disease severity. Compared to past scabies participants in the dermatology clinic, participants with past scabies in the community tended to have a longer delay (median [IQR] 30 [14–48.8] vs 14 [9.5–30] days, p = 0.002). Scabies was associated with health consequences, stigma, and loss of productivity.

Conclusion/Significance

Early diagnosis and effective treatment of scabies can lead to persons less frequently associating scabies with witchcraft and/ or curses. There is the need to enhance health education to promote early care seeking, enhance knowledge of communities on impact and dispel negative perceptions about scabies in Ghana.
Translation and cross-cultural adaptation of heat strain score index (HSSI) into the Malay language
Authors: Lim Mei Ching , Lukman Khamisah Awang , Giloi Nelbon , Jeffree Mohammad Saffree , Saupin Saihpudin Sahipudin , Sidek Zulkhairul Naim , Daud Mohd Nazri Mohd , Andreas Glynn Dexter
Published: February 2023

Concerns about the health and safety of working populations as well as preventive actions to reduce heat-related illnesses and fatalities have intensified as global warming and heatwaves continue to rise as a result of climate change. This study aimed to translate and culturally-adapted the translated Malay version of the Heat Strain Score Index (HSSI) questionnaire so that it can be utilized as a screening tool for heat stress among the Malay-speaking outdoor workers. The original English version of HSSI underwent forward-backward translation and was cross-culturally adapted into the Malay language by bilingual translators based on established guidelines. The content validation was reviewed by a six-member expert committee including the representative of outdoor workers. Face validation was carried out among 10 outdoor workers involved with various work tasks. Psychometric analysis was conducted based on a cross-sectional study among 188 workers who were eligible. Exploratory Factor Analysis (EFA) was used for construct validity while internal consistency reliability was performed using Cronbach’s alpha. The interclass correlation coefficient (ICC) was used to calculate the test-retest reliability. Both content and face validity were acceptable with the overall content validity index being 1.00, while the universal face validity index was 0.83. The factor analysis using varimax rotation extracted four factors which explained 56.32% of the cumulative percentage of variance and factor loading ranging from 0.415 to 0.804. The internal consistency reliability was acceptable with Cronbach’s alpha ranging from 0.705 to 0.758 for all the factors. The overall ICC value was 0.792 (95% CI; 0.764–0.801) which signifies good reliability. The findings from this study indicate that the Malay version of HSSI is a reliable and culturally-adapted instrument. Further validation is needed so that it can be used extensively assess the heat stress among susceptible Malay-speaking outdoor workers in Malaysia who are exposed to hot humid environments.
Serum creatinine in predicting mortality after paraquat poisoning: A systematic review and meta-analysis
Authors: Huang Wei , Zhang Zheng , Lu Yuan-Qiang
Published: February 2023

Although the prognostic value of blood creatinine levels in patients with paraquat (PQ) poisoning has been studied for a long time, the results are still controversial. Therefore, we performed the first meta-analysis to comprehensively assess the value of blood creatinine in predicting the prognosis of patients with PQ poisoning. We searched PubMed, EMBase, Web of Science, ScienceDirect, Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal Database, and China Online Journals to identify all relevant papers published up to June 2022. Data were extracted for pooled analysis, heterogeneity testing, sensitivity analysis, publication bias analysis, and subgroup analysis. Ultimately, 10 studies involving 862 patients were included. The I2 of diagnostic odds ratio (DOR), sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of this study were all greater than 50%, which showed the existence of heterogeneity in this study, and a random effects model was used for the combination of the above five effect sizes. Pooled analysis showed a high predictive value of blood creatinine for prognosis of PQ poisoning [pooled DOR:22.92, 95% confidence interval (CI):15.62–33.65, P < 0.001]. The combined sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were 86% (95% CI: 0.79–0.91), 78% (95% CI: 0.69–0.86), 4.01 (95% CI: 2.81–5.71), and 0.17 (95% CI: 0.12–0.25), respectively. Deeks publication bias test revealed there was publication bias. Sensitivity analysis showed no significant differences in the estimates of impact. Serum creatinine is an effective predictor of mortality in patients with PQ poisoning.
Using JAWS digest: Playing the game of academic writing in an educational setting: A report
Authors: Côrte-Real Eduardo
Published: February 2023

This article reports on the work developed on the first semester of the 2020–21 academic year in a curricular unit called art and visual culture belonging to the curriculum of the master’s course in design and visual culture at IADE, Faculty of Design, Technology and Communication of Universidade Europeia, Lisbon, Portugal. For the students’ work – to write an academic article – we used JAWS as a template for a hypothetical submission. Each student developed one article as if to submit for publication in this journal. The work was divided into two phases: research and writing. In the first phase, art and humanities methods were explored, concerning reading and organizing textual and visual materials. Gillian Rose’s Visual Methodologies and Aby Warburg’s Mnemosyne method were explored. Students chose one exhibition held in Lisbon at the time to be the subject of the article. A ‘Warburg panel’ was created, bringing depth in analysis linking contemporary art or visual culture with Romanticism and or Modernism. In the second phase, writing was structured organizing a visual rhetoric deriving from the images already collected. Textual strategies like paraphrasing, quoting and commenting were also explored to finalize an article using a defined article already published by JAWS about an exhibition held in Portugal. The article concludes on the virtue of using academic journals as a learning tool.
Photographic realism, camera-less photography and the representation of the feminine: The work of Floris Neusüss
Authors: Collins Hattie
Published: February 2023

This article will examine claims that photography can reveal truths about the world with a particular emphasis on camera-less techniques, their claim to realism and their utilization in both late nineteenth-century science and contemporary art photography. I will critique the late twentieth-century work of Floris Neusüss, whose photograms of the unclothed female form were exhibited in the Victoria and Albert Museum in London in 2010. It will be argued that the photogram slips the grasp of contemporary gender analysis within visual culture, despite the camera-less process’s associations with a tactful, scientific truth. Understood through their psychoanalytic subtext, Neussus’s images are revealed as compliant with well-worn clichés of female passivity, both in what they represent and in the singularity of their method of production.
On Living with Television, Amy Holdsworth (2021)
Authors: Samuel Michael
Published: February 2023

Review of: On Living with Television, Amy Holdsworth (2021)

Durham, NC and London: Duke University Press, 192 pp.,

ISBN 978-1-47801-475-1, p/bk, $24.95
The utility of two-dimensional shear wave elastography for predicting prostate cancer: a preliminary study
Authors: Jeon Seong Soo , Kim Chan Kyo , Park Sung Yoon , Chung Jae Hoon , Kang Minyong , Sung Hyun Hwan , Jeong Byong Chang
Published: February 2023

Purpose: This study investigated whether two-dimensional shear wave elastography (2D-SWE), using a newly developed device, is useful for predicting prostate cancer (PCa).Methods: In this prospective study, 38 patients with suspected PCa underwent 2D-SWE, followed by a standard systematic 12-core biopsy with and without a targeted biopsy. Tissue stiffness on SWE was measured in the target lesion and in 12 regions of the systematic biopsies, and the maximum (Emax), mean (Emean), and minimum (Emin) values of stiffness were generated. The area under the receiver operating characteristic curve (AUROC) for predicting clinically significant cancer (CSC) was calculated. Interobserver reliability and variability were evaluated using the intraclass correlation coefficient (ICC) and Bland-Altman plots, respectively.Results: PCa was found in 78 of 488 regions (16%) in 17 patients. In region-based and patientbased analyses, the Emax, Emean, and Emin values of PCa were significantly higher than those of benign prostate tissue (P<0.001). For the prediction of CSC, the AUROCs of Emax, Emean, and Emin in the patient-based analysis were 0.865, 0.855, and 0.828, while that of prostate-specific antigen density was 0.749. In the region-based analysis, the AUROCs of Emax, Emean, and Emin values were 0.772, 0.776, and 0.727, respectively. The interobserver reliability for the SWE parameters was moderate to good (ICC, 0.542 to 0.769), and the mean percentage differences on Bland-Altman plots were less than 7.0%.Conclusion: The 2D-SWE method appears to be a reproducible and useful tool for the prediction of PCa. A larger study is warranted for further validation.
Investigation of the cutting force and surface profile error when free form milling
Authors: Varga Bálint , Mikó Balázs
Published: February 2023

Machining free-form shaped surfaces is a widespread task. Aerospace, automotive, mould making and many other sectors are challenged by ever increasing demands for precision and economy. In ball-end milling, the constantly changing cutting conditions affect the shape and volume of the chip, as well as the tool load and the quality of the resulting surface. It is important to know the cutting force for a given surface characteristic, because this makes it easier to plan the machining process. The prediction of cutting forces is very important for optimising machining strategies and parameters to achieve the required accuracy. In the experiments, the forces on the tool and the surface geometric accuracy were measured by milling test surfaces of 42CrMo4 with different cutting parameters. Based on the measured values, the average cutting force was determined, the variance of the force variation was investigated and the force momentum, which takes into account the machining time. The aim of this paper is to investigate and compare the cutting force and the surface profile error of the resulting surface during finishing milling with a ball-end milling cutter.
ANALISIS SUPPORT VECTOR REGRESSION (SVR) DENGAN ALGORITMA GRID SEARCH TIME SERIES CROSS VALIDATION UNTUK PREDIKSI JUMLAH KASUS TERKONFIRMASI COVID-19 DI INDONESIA
Authors: Safira Anindita Nur , Warsito Budi , Rusgiyono Agus
Published: February 2023

Coronavirus Disease 2019 or Covid-19 is a group of types of viruses that interfere with the respiratory tract associated with the seafood market that emerged in Wuhan City, Hubei Province, China at the end of 2019. The first confirmed cases of Covid-19 in Indonesia on March 2, 2020, were 2 cases and until the end of 2021, it continues to grow every day. The purpose of this study was to predict the number of confirmed cases of Covid-19 in Indonesia using the Support Vector Regression (SVR) method with linear kernel functions, radial basis functions (RBF), and polynomials. Support Vector Regression (SVR) is the application of a support vector machine (SVM) in regression cases that aims to find the dividing line in the form of the best regression function. The advantage of the SVR model is can be used on time series data, data that are not normally distributed and data that is not linear. Parameter selection for each kernel used a grid search algorithm combined with time series cross validation. The criteria used to measure the goodness of the model are MSE (Mean Square Error), MAPE (Mean Absolute Percentage Error) and R2 (Coefficient of Determination). The results of this study indicate that the best model is Support Vector Regression (SVR) with a polynomial kernel and the parameters used include Cost = 1, degree = 1, and coefficient = 0.1. The polynomial kernel SVR model produces a MAPE value of 0.4946215%, which means the model has very good predictive ability. The prediction accuracy obtained with an R2 value of 85.65011% and an MSE value of 161606.1.
PENGARUH KONVEKSITAS TERHADAP SENSITIVITAS HARGA JUAL DAN DELTA-NORMAL VALUE AT RISK (VAR) PORTOFOLIO OBLIGASI PEMERINTAH MENGGUNAKAN DURASI EKSPONENSIAL
Authors: Devitasari Putri , Maruddani Di Asih I , Kartikasari Puspita
Published: February 2023

Bonds are one of the investment instruments issued by the issuer as proof of debt.  Bond investment is relatively safe, but it is possible for investors to experience losses. Investors should always consider that trading a bond is always risky. One of the important bond risks is interest risk. The concept of duration can only explain well for small changes in interest rates but cannot explain well for large changes in interest rates. The estimation of the duration concept will have a larger calculation error with the greater changes in market interest rates that occur so it is necessary to add convexity to improve accuracy. This study aims to estimate the risk of government bonds based on the estimation of bond prices with the effect of convexity. Several studies have shown that exponential duration can predict bond prices more accurately than Macau duration. Exponential duration with convexity will be applied in this study to measure the accurate value of bond prices caused by changes in interest rates. The Delta-Normal VaR portfolio method is used to calculate risk based on estimated bond prices in the form of a portfolio. The formation of this portfolio aims to reduce the losses suffered by investors. This method is applied to four Indonesian government bonds with codes FR0056, FR0059, FR0074, and FR0080. The results showed that the bonds portfolio FR0056 and FR0074 had the smallest risk compared to other portfolios with a weight proportion of 15% for bonds FR0056 and 85% for bonds FR0074.
Connections and genuinely ramified maps of curves
Authors: Biswas Indranil , Machu Francois-Xavier , Parameswaran A. J.
Published: February 2023

Given a singular connection D on a vector bundle E over an irreducible smooth projective
curve X, defined over an algebraically closed field, we show that there is a unique maximal
subsheaf of E on which D induces a nonsingular connection. Given a generically smooth
map

ϕ
:

Y
→
X

{\phi:Y\rightarrow X}

between irreducible smooth projective
curves, and a singular connection

(
V
,
D
)

{(V,D)}

on Y, the direct image

ϕ
*

⁢
V

{\phi_{*}V}

has
a singular connection. Let

𝐑
⁢

(

ϕ
*

⁢

𝒪
Y

)

{\mathbf{R}(\phi_{*}{\mathcal{O}}_{Y})}

be the unique maximal subsheaf
on which the singular connection on

ϕ
*

⁢

𝒪
Y

{\phi_{*}{\mathcal{O}}_{Y}}

– corresponding
to the trivial connection on

𝒪
Y

{{\mathcal{O}}_{Y}}

– induces a nonsingular connection.
We prove that the homomorphism of étale fundamental groups

ϕ
*

:

π
1
et

⁢

(
Y
,

y
0

)

→

π
1
et

⁢

(
X
,

ϕ
⁢

(

y
0

)

)

{\phi_{*}:\pi_{1}^{\rm et}(Y,y_{0})\rightarrow\pi_{1}^{\rm et}(X,\phi(y_{0}))}

induced by
ϕ is surjective if and only if

𝒪
X

⊂

𝐑
⁢

(

ϕ
*

⁢

𝒪
Y

)

{{\mathcal{O}}_{X}\subset\mathbf{R}(\phi_{*}{\mathcal{O}}_{Y})}

is the unique maximal
semistable subsheaf.
When the characteristic of the base field is zero, this homomorphism

ϕ
*

{\phi_{*}}

is surjective if and only if

𝒪
X

=

𝐑
⁢

(

ϕ
*

⁢

𝒪
Y

)

{{\mathcal{O}}_{X}=\mathbf{R}(\phi_{*}{\mathcal{O}}_{Y})}

. For any nonsingular connection D on a vector bundle V over X, there
is a natural map

V
↪

𝐑
⁢

(

ϕ
*

⁢

ϕ
*

⁢
V

)

{V\hookrightarrow\mathbf{R}(\phi_{*}\phi^{*}V)}

. When the characteristic of the base field is
zero, we prove that the map ϕ is genuinely ramified if and only if

V
=

𝐑
⁢

(

ϕ
*

⁢

ϕ
*

⁢
V

)

{V=\mathbf{R}(\phi_{*}\phi^{*}V)}

.
A classification of finite primitive IBIS groups with alternating socle
Authors: Lee Melissa , Spiga Pablo
Published: February 2023

Let 𝐺 be a finite permutation group on Ω.
An ordered sequence

(

ω
1

,
…
,

ω
ℓ

)

(\omega_{1},\ldots,\omega_{\ell})

of elements of Ω is an irredundant base for 𝐺 if the pointwise stabilizer is trivial and no point is fixed by the stabilizer of its predecessors.
If all irredundant bases of 𝐺 have the same cardinality, 𝐺 is said to be an IBIS group.
Lucchini, Morigi and Moscatiello have proved a theorem reducing the problem of classifying finite primitive IBIS groups 𝐺 to the case that the socle of 𝐺 is either abelian or non-abelian simple.
In this paper, we classify the finite primitive IBIS groups having socle an alternating group.
Moreover, we propose a conjecture aiming to give a classification of all almost simple primitive IBIS groups.
Evidential-perceptual transfer by a blind speaker? Or: what do the Ladakhi markers for “visual” and “non-visual” perceptual experience, ḥdug and rag, actually encode?
Authors: Zeisler Bettina
Published: February 2023

A typical trait of the modern Tibetic languages is that speakers obligatorily encode the knowledge base for their statements: whether they have intimate and/or authoritative knowledge of a situation, whether they have merely perceived a situation, whether they have merely inferred (or presumed etc.) a situation, whether they have second-hand knowledge, or even whether their knowledge is shared with the addressee or the larger community. In most of the Tibetic languages, speakers do not differentiate between different perceptual channels. By contrast, in most of the Ladakhi dialects, speakers appear to differentiate between visual perception, using the auxiliary ḥdug (or snaṅ), and sense perception through other channels, using the auxiliary rag. This opposition needs to be reanalysed based on the observation of how a congenitally blind speaker deals with these two options and upon certain unexpected choices made by non-handicapped speakers.