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This article aims at laying the foundation for the development of electronic structure–property relationships in the field of charge-transfer (CT) organic semiconductors by studying the low-frequency phonon response of donor–acceptor (DA) compounds. In this article, it is shown and discussed how and why phonon frequencies and their delocalization depend on the interplay between single-molecule properties and crystal structures. These results are obtained by combining results from state-of-the-art quantum–mechanical calculations, carried out within both localized orbitals and a plane wave paradigm, with simple classical models. CT compounds obtained from perylene (Pery) as the donor and FnTCNQ (n= 0, 4) as the acceptors are considered.

ABSTRACT Nano-sized Ti[O.sub.2] is widely used as photocatalysts for many applications; however, some aspects in the application in cultural heritage conservation are still unresolved. In particular, in this research, we [...]

Polarized low-frequency Raman microscopy and a posteriori dispersion-corrected density functional simulations are combined to investigate the lattice vibrations of the αI, β, and γ polymorphs of the model organic semiconductor quinacridone, which are known to display different optical and electronic properties. The comparison between experiments and calculations allows for unambiguous mode assignment and identification of the scattering crystal faces. Conversely, the agreement between simulations and experiments validates the adopted computational methods, which correctly describe the intermolecular interaction of the molecular material. The acquired knowledge of quinacridone lattice dynamics is used to describe the αIto β thermal transition and, most consequentially, to reliably characterize the electron–lattice phonon coupling strength of the three polymorphs, obtaining hints about the electrical transport mechanism of the material.

The Italian official height system is defined through a high precision levelling network established and maintained by the Istituto Geografico Militare - IGM. During the last 20 years, IGM has performed levelling campaigns on almost the whole peninsular area of Italy with the aim of both densifying the existing network and updating the reference heights. This paper reports about the procedure applied to correct the levelling observations for the gravity effects and the assessment on the results. The needed gravity values were predicted from the Italian gravity dataset (IGD), and both from EGM2008 and XGM2019e high resolution global gravity models. A new formulation of the normal correction as well as the standard orthometric correction were applied. The IGD derived corrections proved to be effective by reducing the misclosure error of critical loops below the tolerance level. Gravity data derived from EGM2008 and XGM2019e proved to be too poor for the correction purposes, as it was also confirmed by a comparison against available observed data, with RMS of the differences, in Alpine ares, ranging between 50 and 100 mGal.

In the field of organic electronics, the semiconductor 7-decyl-2-phenyl[1]benzothieno[3,2-b][1]benzothiophene (Ph-BTBT-10) has become a benchmark due to its high charge mobility and chemical stability in thin film devices. Its phase diagram is characterized by a crystal phase with a bilayer structure that at high temperature transforms into a Smectic E liquid crystal with monolayer structure. As the charge transport properties appear to depend on the phase present in the thin film, the transition has been the subject of structural and computational studies. Here such a process has been investigated by polarized low frequency Raman spectroscopy, selectively probing the intermolecular dynamics of the two phases. The spectroscopic observations demonstrate the key role played by a displacive component of the transition, with the interpenetration of the crystal bilayers driven by lattice phonon mode softening followed by the intralayer rearrangement of the molecule rigid cores into the herringbone motif of the liquid crystal. The mechanism can be related to the effectiveness of thermal annealing to restore the crystal phase in films.

Abstract:In this excerpt, a woman reflects on her sexual encounters with men, most of which took place in a car parked in a field that belonged to her grandfather.

A series of methanesulfonate salts with various globular cations, including the achiral 3-quinuclidonium [QHco]+, the racemic (3)-hydroxyquinuclidinium [QHrac]+, and the enantiopure (3)-hydroxyquinuclidinium R-[QH]+, have been synthesized and structurally characterized. Despite the high degree of similarity among components, only the enantiopure salt R-[QH]MS was found to undergo a reversible plastic transition at high temperature. Electrochemical impedance spectroscopy was successfully applied to study proton conductivity associated with temperature variations and the plastic phase transition under inert and dry conditions. Ionic conductivity at RT was lower than 10–11S cm–1and drastically increased up to 1.03 × 10–3S cm–1at 145 °C due to the onset of the plastic phase transition.

Large spin–orbit torques (SOTs) generated by topological materials and heavy metals interfaced with ferromagnets are promising for next-generation magnetic memory and logic devices. SOTs generated from yspin originating from spin Hall and Edelstein effects can realize field-free magnetization switching only when the magnetization and spin are collinear. Here we circumvent the above limitation by utilizing unconventional spins generated in a MnPd3thin film grown on an oxidized silicon substrate. We observe conventional SOT due to yspin, and out-of-plane and in-plane anti-damping-like torques originated from zspin and xspin, respectively, in MnPd3/CoFeB heterostructures. Notably, we have demonstrated complete field-free switching of perpendicular cobalt via out-of-plane anti-damping-like SOT. Density functional theory calculations show that the observed unconventional torques are due to the low symmetry of the (114)-oriented MnPd3films. Altogether our results provide a path toward realization of a practical spin channel in ultrafast magnetic memory and logic devices.

Background and Objectives: Being highly consumed by the population for nutritional purposes, the monitoring of radionuclides in milk represents a very important task for the protection of human health. The present paper reports the results of an investigation aimed at determining the natural and anthropogenic radioactivity content in milk and assessing the radiological health risks due to its ingestion. Methods: Liquid for infants, Ultra Heat Treated (UHT) sheep, UHT cow, and UHT goat milk samples, coming from Italian large retailers, were investigated. In particular, a total of twenty samples, five for each type, were analyzed by using High Purity Germanium (HPGe) gamma-ray spectrometry, with the ultimate goal of quantifying the specific activity of natural and anthropic radionuclides (4400K and 137Cs, respectively). The evaluation of dose levels due to the milk ingestion was also performed for six age categories, namely infants, 1-5, 5-10, 10-15, 15-17 years old, and adults (> 17 years old), taking into account the average yearly direct consumption in Italy and under the a priori hypothesis that this need can be satisfied by a single variety of milk. Results: The mean specific activity of 40K varies from (30 ± 4) Bq L-1 to (48 ± 6) Bq L-1; the lowest value was obtained for the UHT sheep milk, while the highest one for the UHT cow milk, with investigated Italian large retailers milk samples presenting an activity concentration of (38 ± 5) Bq L-1 on average. The 137Cs specific activity is lower than the minimum detectable activity (MDA) value for all investigated samples. Regarding the dose levels due to the milk ingestion, the obtained values remain below the threshold value of 1 mSv y-1 set by the Italian legislation. Conclusion: Reported results then show that the radiation dose incurred from the ingestion of the investigated milk samples poses no significant health effect on the population from a radiological point of view.

The discovery of new polymorphs opens up unique applications for molecular materials since their physical properties are predominantly influenced by the crystal structure type. The deposition of molecules at surfaces offers great potential in the variation of the crystallization conditions, thereby allowing access to unknown polymorphs. With our surface crystallization approach, four new phases are found for an oligoethylene glycol-benzothienobenzothiophene molecule, and none of these phases could be identified viaclassical polymorph screening. The corresponding crystal lattices of three of the new phases were obtained viaX-ray diffraction (XRD). Based on the volumetric considerations together with X-ray fluorescence and Raman spectroscopy data, the phases are identified as solvates containing one, two or three solvent molecules per molecule. The strong interaction of dichloromethane with the oligoethylene glycol side chains of the molecules may be responsible for the formation of the solvates. Temperature-dependent XRD reveals the low thermal stability of the new phases, contrary to the thermodynamically stable bulk form. Nevertheless, the four solvates are stable under ambient conditions for at least two years. This work illustrates that defined crystallization at surfaces enables access to multiple solvates of a given material through precise and controlled variations in the crystallization kinetics.

This study applies methods used in sign language and gesture research to better understand reduced imitation accuracy (IA) of actions and gestures in children with autism spectrum disorder (ASD), and we addressed contrasting theories on IA in ASD and the role of objects and meanings in imitation. Eight male children with ASD with a mean chronological age (CA) of 86.76 months (SD= 10.74, range 70.5–104.4) and 22 male and female peers with typical development (TD) and a mean CA of 85.44 months (SD= 7.95, range 73.4–96.7) imitated videos of an adult performing actions with objects, representational gestures, conventional gestures and meaningless gestures. We measured accuracy as ability to effectively reproduce features (handshape, palm orientation, location, movement direction and type) and timing (speed) of observed actions/gestures, after ruling out cases of specular (i.e., mirror-like) versus anatomical imitation. Results highlighted significantly lower feature and timing accuracy in children with ASD with respect to the TD group across tasks, and these findings supported sensory-motor theories of IA in ASD. Our data also showed the different impact of objects and meanings within groups. Overall, these results suggest validity to our assessment method and suggested the importance of considering both discreet variables (i.e., variables describing action/gesture feature accuracy, e.g. handshape, movement direction) and continuous variables (i.e., kinematic variables, e.g. speed) in evaluating IA in autism.

Purpose: Skeletal maturity assessment may be performed using low-dose scoliosis radiographs (LDSS) with simultaneous imaging of the hand or proximal humerus. We sought to compare the practicality, reliability and validity of the Sanders skeletal maturity staging (SMSS), proximal humerus ossification system (PHOS) and the thumb ossification composite index (TOCI) as skeletal maturity assessment tools using LDSS. Methods: A survey including 85 LDSS and 42 hand radiographs was administered to four orthopedic clinicians. Each rater assessed the TOCI, SMSS and PHOS stage for each image. Standing LDSS with hands at the patient’s side were used for TOCI, SMSS, and PHOS measurements. SMSS and TOCI measurements on dedicated hand radiographs were assessed as a comparison. Interobserver reliability was calculated for each scale using Fleiss’ kappa. For SMSS and TOCI, intraobserver correlation between measurements on LDSS and measurements on hand radiographs were also assessed. Results: 472 TOCI measurements, 288 SMSS measurements, and 340 measurements were collected. Kappa interobserver reliability for TOCI was 0.79 (strong) using hand radiographs and 0.74 (strong) using LDSS. Kappa for SMSS was 0.66 (strong) using hand radiographs and 0.45 (moderate) using LDSS. Kappa for PHOS was 0.51 (moderate) using LDSS. Intraobserver agreement between LDSS and hand imaging averaged 0.78 (strong) for TOCI and 0.34 (weak) for SMSS. Conclusion: Skeletal maturity assessment with TOCI using LDSS demonstrates strong interobserver reliability when hands are placed at the patient’s side and correlates well with assessment on hand radiographs. TOCI achieved better inter- and intraobserver reliability compared to SMSS and PHOS, likely because the thumb readily assumes a good position in standing scoliosis sterioradiographs. Level of evidence: Diagnostic—Level III.

Pension underfunding is a problem for all types of pension plans. Using a case study of a defined benefit plan, this article identifies funding problems and their causes, such as plan performance, plan design and actuarial cost methods. Tough decision making about funding and benefits should be made with the assistance of plan professionals and sensitivity to plan member needs. Plan funding must be strengthened so the plan can continue to provide benefits predictably and reliably.

The International Accounting Standards Board (IASB) has found the task of establishing standards on accounting for financial instruments, including derivatives, as challenging as FASB has. The international guidance on accounting [...]

The Sarbanes-Oxley Act of 2002 represents the most significant securities law reforms since the Securities Act of 1933 and the Securities Exchange Act of 1934. Due to widespread outrage over [...]

In 2001, a record 257 publicly traded companies, with a combined $258.5 billion in assets, filed for bankruptcy, more than doubling the annual average for the previous decade, according to [...]

On October 16, 2001, Enron's routine announcement of $0.43 recurring third-quarter earnings per share led to a series of events that would bankrupt this global Fortune 10 corporation, inaugurate an [...]

The media scrutiny of the Enron-Andersen case has obscured relevant auditing and accounting issues. Although apparent loopholes in the application of accounting standards may have enhanced Enron's ability to manipulate [...]

A model of user interfaces for information retrieval (IR) that provides strategic support in a collaborative coaching framework is proposed. The model is implemented, evaluated and shown to be effective.

The use of the Okapi information retrieval system in the Tools for Innovative Publishing in Science High Energy Physics project is analyzed. Opportunities and challenges are presented by the World Wide Web-based environment.

Issues related to procedures of the IRS advance pricing agreement (APA) program are examined, focusing on recommendations by members of Arthur Andersen LLP. Topics include the importance of cooperation and consistency, efficient management of cases, relationship between filing of tax returns and APA processing, and discrepancy between terms of APA and actual results.

Introduction: Following the Covid-19 pandemic spread, changes in clinical practice were necessary to limit the pandemic diffusion. Also, oncological practice has undergone changes with radiotherapy (RT) treatments playing a key role. Methods: A Pubmed/MEDLINE and Embase systematic review was conducted. The search strategy was “Covid AND Radiotherapy” and only original articles in the English language were considered. Results: A total of 2.733 papers were obtained using the mentioned search strategy. After the complete selection process, a total of 281 papers were considered eligible for the analysis of the results. Discussion: RT has played a key role in Covid-19 pandemic as it has proved more resilient than surgery and chemotherapy. The impact of the accelerated use of hypofractionated RT and telemedicine will make these strategies central also in the post-pandemic period.

Community science projects offered in urban areas may be particularly effective at addressing environmental problems and engaging people in science, especially individuals whose identities have historically been underrepresented in the field. In this project, we worked with individuals from a racially diverse, low‐income community in San Diego, California to conduct community science to: 1) test a conceptual program model aimed at engaging diverse communities in science, and 2) contribute to scientific knowledge about the inputs and accumulations of trash in an urban watershed. While the program model did well at bolstering environmental stewardship, recruitment, and short‐term retention of community members as project participants, it was not as effective at building science understanding, interest in science, and awareness of doing science, indicating a need for a mindset approach. Despite this, the data collected by the community between 2014–2018 revealed in‐depth information about the spatial and temporal distributions of trash, including the identification of three main debris inputs: encampments, illegal dumping, and storm drain flows, as well as the validation of global trends of a predominance of plastics across waterways and through time. In a few instances, community stewards became community scientists—the quantity and quality of data collected improved, and community members presented results to authorities who responded with concordant management actions (e.g., help with cleanups, outreach to unhoused communities). Based on project outcomes, our revised community science program model includes a focus on strengthening a science mindset, in which even short‐term science interventions that improve the recognition of science, a sense of belonging, and access to mentorship may have meaningful long‐lasting effects on increased participation in science.

The 1993 temporary and proposed regulations for transfer pricing taxation give more flexibility to businesses and are a major change from the proposed rules of 1992. The temporary rules come under IRC section 482, while the new proposed rules come under IRC sections 6664 and 6662. The rules include the arm's length standard, comparability of transactions and an increased requirement for documentation to verify arm's length practices.