Static Disorder Research Articles

Reducing Voltage Losses in Organic Photovoltaics Requires Interfacial Disorder Management

AbstractThanks to the introduction of non‐fullerene acceptors, efficiencies of organic photovoltaics are now approaching 20%. Closing the gap with inorganic photovoltaics requires minimizing voltage losses without penalizing charge extraction, for which microstructure control is crucial. However, the complex interplay between microstructure and charge generation, recombination, and extraction has so far not been unraveled. Here, a systematic study linking device performance to distinct microstructural features via machine learning is presented. Building bi‐layer devices allows to separately study the influence of aggregation and disorder on the energies and lifetimes of bulk and interfacial states. Unambiguous assignments of specific structural motifs to the device photophysics are thus possible. It is found that the control of aggregation‐caused quenching is decisive for the exciton splitting efficiency and thus the carrier generation. Furthermore, the static disorder at the donor–acceptor interface controls the nonradiative recombination by shifting the excited state population from the bulk toward the interface. Finally, the amount of disorder in the bulk is found decisive for charge extraction. The finding that charge generation, recombination, and extraction are controlled by distinct structural features, is the key to optimizing these motifs independently, which will pave the way for organic photovoltaics toward the detailed balance limit.

Pressure-Induced Suppression of Static Disorder and Lattice Distortion in Pyrochlore Bi2Ru2O7

Pressure-Induced Suppression of Static Disorder and Lattice Distortion in Pyrochlore Bi₂Ru₂O₇

Static and dynamic disorder in ion-implanted silica glass

Structural disorder in solid-state materials has a direct impact on the complex of its physicochemical properties and functional characteristics of developed devices. The purpose of this work is to establish the influence of ion irradiation of SiO2 glass on static and dynamic disorder separately. Silica glasses implanted with carbon ions were studied using optical absorption spectroscopy and Raman spectroscopy. The temperature behavior of the fundamental absorption edge was considered in terms of the Urbach rule. The dose dependences of the root-mean-square atomic displacements caused by static and dynamic disorder were obtained. Analysis of Raman spectra confirmed the optical spectroscopy data and revealed a decrease in the medium-range order size along with topological changes in the SiO2 structure after ion implantation. The described step-by-step technique for quantitatively assessing the degree of static and dynamic disorder is universal and can be used to analyze other materials.

Femtosecond Electron Diffraction Reveals Local Disorder and Local Anharmonicity in Thermoelectric SnSe.

In addition to long-range periodicity, local disorder, with local structures deviating from the average lattice structure, dominates the physical properties of phonons, electrons, and spin subsystems in crystalline functional materials. Experimentally characterizing the 3D atomic configuration of such a local disorder and correlating it with advanced functions remains challenging. Using a combination of femtosecond electron diffraction, structure factor calculations, and time-dependent density functional theory molecular dynamics simulations, the static local disorder and its local anharmonicity in thermoelectric SnSe are identified exclusively. The ultrafast structural dynamics reveal that the crystalline SnSe is composed of multiple locally correlated configurations dominated by the static off-symmetry displacements of Sn (≈0.4 Å) and such a set of locally correlated structures is termed local disorder. Moreover, the anharmonicity of this local disorder induces an ultrafast atomic displacement within 100 fs, indicating the signature of probable THz Einstein oscillators. The identified local disorder and local anharmonicity suggest a glass-like thermal transport channel, which updates the fundamental insight into the long-debated ultralow thermal conductivity of SnSe. The method of revealing the 3D local disorder and the locally correlated interactions by ultrafast structural dynamics will inspire broad interest in the construction of structure-property relationships in material science.

Acellular Dermal Matrices as an New Alternative for Treatment in Reproductive Organ Static Disorders: A Pilot Study.

Background: The study aimed to evaluate the clinical effects of utilizing acellular dermal matrix (ADM) for treating pelvic organ prolapse. The motivation behind exploring a new treatment method stems from the limited efficacy of current surgical options, which are often associated with side effects. Methods: Ten patients with reproductive organ prolapse underwent surgery at the Chair and Department of Gynecology, Obstetrics, and Gynecological Oncology in Katowice. ADM was used as a support material, with eight patients receiving double TOT and two undergoing a six-point fixation mesh procedure. Pelvic organ prolapse was evaluated pre-operatively and one month post-surgery using the Pelvic Organ Prolapse Quantification (POP-Q) System. General medical history and complaints were assessed using the short form (PFDIQ-SF20). The study included ten patients aged 39 to 71 (mean: 63.6 years), all with a history of at least one vaginal delivery (mean of two). None had undergone a cesarean section. Four patients exhibited POP-Q 3, and five had POP-Q 2. Results: The mean PFDIQ-SF20 score before surgery was 70.6 points. No major complications occurred during or after surgery. One patient experienced a vaginal fungal infection and an allergic reaction to sutures. Post-operation, ailments reduced by an average of 60.76 points, with five patients reporting no complaints. Conclusions: ADM emerges as a material of interest for gynecological surgery, with initial reports highlighting its effectiveness and optimistic safety profile. Further research is warranted to explore its potential as a promising option in pelvic organ prolapse treatment.

Foot involvement in psoriatic arthritis: Prevalence, clinical and radiological features

BackgroundThe purpose of this study was to evaluate the prevalence of foot involvement in psoriatic arthritis and to describe its different clinical and radiological features. Patients and MethodsWe conducted a cross sectional study including 40 patients with psoriatic arthritis over a period of 12 months. Anamnesis, clinical examination of feet, podoscopic examination, X-rays of feet and heels, and ultrasound in B mode and power Doppler mode were done for each patient. ResultsFoot involvement was found in 95% of cases. It was symptomatic in 70% and inaugural of the disease in 20% of cases. The hindfoot and the forefoot were the sites most affected (77.5% and 47.5% respectively). The involvement of the midfoot was rarer (25%). Dactylitis was found in 17.5% and deformities of forefoot were found in 22.5% of cases. Antalgic gait was noted in 17.5% and static disorders of foot at podoscopic examination were identified in 35% of cases. Feet dermatological manifestations were found in 45% of cases. Diagnosis of different rheumatological manifestations was based on clinical findings and caracteristic radiological images on X-rays. We demonstrate he sensitivity of ultrasound in the detection and the diagnosis of different foot lesions including enthesitis, synovitis and tenosynovitis, dactylitis, bone erosions and psoriatic nail dystrophy.

Coherent Transient Localization Mechanism of Interchain Exciton Transport in Regioregular P3HT: A Quantum-Dynamical Study.

Transient localization has been proposed as a transport mechanism in organic materials, for both charge carriers and excitons. Here, we characterize a quantum coherent transient localization mechanism using full quantum simulations of an H-aggregated model system representative of regioregular poly(3-hexylthiophene) (rrP3HT). A Frenkel-Holstein Hamiltonian parametrized from first principles is considered, including local high-frequency modes and anharmonic, site-correlated interchain modes. Quantum-dynamical calculations are carried out using the Multi-Layer Multi-Configuration Time-Dependent Hartree (ML-MCTDH) method for a 13-site system with 195 vibrational modes, under periodic boundary conditions. It is shown that temporary localization of exciton polarons alternates with resonant transfer driven by interchain modes. While the transport process is mainly determined by exciton-polarons at the low-energy band edge, persistent coupling with the excitonic manifold is observed, giving rise to a nonadiabatic excitonic flux. This elementary transport mechanism remains preserved for limited static disorder and gives way to Anderson localization when the static disorder becomes dominant.

Impact of static foot disorders on the conservative treatment success in chronic venous disease patients without wounds

ObjectiveChronic venous disease (CVD) and static foot disorders (SFDs) are prevalent conditions that commonly cause lower extremity pain. These conditions share common factors such as age and weight in their etiology. This study aimed to investigate the impact of SFDs on the treatment response of patients undergoing conservative treatment for CVD without wounds. Materials and MethodsA retrospective evaluation was conducted on 328 patients (60 males, 268 females) with CVD. Parameters including age, gender, affected side, body mass index, Visual Analog Scale (VAS), Clinical-Etiological-Anatomical-Pathophysiological (CEAP) classification, and revised Venous Clinical Severity Score (rVCSS) were considered for evaluation. Radiological measurements of calcaneal pitch angle (CPA) were analyzed as a determinant of SFDs. ResultsVAS and rVCSS of the patients were evaluated before and after conservative treatment of CVD without concomitant treatment of SFDs. The presence of SFDs was associated with decreased treatment success (P < .001). Among different types of SFDs, the pes cavus group exhibited the lowest change in VAS and rVCSS scores before and after conservative CVD treatment. In contrast, the normal group demonstrated the highest improvement. Patients with a normal foot medial arch consistently achieved the best treatment outcomes compared with patients with other SFDs. ConclusionsIn conclusion, SFDs affect outcomes of conservative treatment of CVD in CEAP 0 to 3 patients, with the efficacy of treatment dependent upon the severity of SFDs.

Path Integral over Equivalence Classes for Quantum Dynamics with Static Disorder.

An efficient, fully quantum mechanical, real-time path integral method for including the effects of static disorder in the dynamics of systems coupled to common or local harmonic baths is presented. Rather than performing a large number of demanding calculations for different realizations of the system Hamiltonian, the influence of the bath is captured through a single evaluation of the path sum by grouping the system paths into equivalence classes of fixed system amplitudes. The method is illustrated with several analytical and numerical examples that show a variety of nontrivial effects arising from the interplay among coherence, dissipation, thermal fluctuations, and geometric phases.

Unveiling the Structural and Optical Properties of MgAl2O4 Single Crystals Irradiated by Swift Heavy Ions.

A synthetic single crystal of magnesium-aluminate spinel was irradiated perpendicularly to the (111) plane with swift heavy xenon ions with an energy of 220 MeV. The modified layer was attested based on Raman scattering spectra recorded while focusing on the surface. A decrease in surface crystallinity was observed, reflected in the changes in fundamental optical characteristics such as the band gap and the energies of static and dynamic disorder. In this study, we demonstrate, along with the modification of optical characteristics and the formation of a disordered layer, the creation of new optically active centers. The luminescent properties of these centers were analyzed. The effect of temperature flare-up in the 3.4 eV band of the excitation spectrum was determined. The low sensitivity of Cr3+ luminescence to SHI is demonstrated.

Characterizing quantum gases in time-controlled disorder realizations using cross-correlations of density distributions

The role of disorder on physical systems has been widely studied in the macroscopic and microscopic world. While static disorder is well understood in many cases, the impact of time-dependent disorder on quantum gases is still poorly investigated. In our experimental setup, we introduce and characterize a method capable of producing time-controlled optical-speckle disorder. Experimentally, coherent light illuminates a combination of a static and a rotating diffuser, thereby collecting a spatially varying phase due to the diffusers’ structure and a temporally variable phase due to the relative rotation. Controlling the rotation of the diffuser allows changing the speckle realization or, for future work, the characteristic time scale of the change of the speckle pattern, i.e. the correlation time, matching typical time scales of the quantum gases investigated. We characterize the speckle pattern ex-situ by measuring its intensity distribution cross-correlating different intensity patterns. In-situ, we observe its impact on a molecular Bose–Einstein condensate (BEC) and cross-correlate the density distributions of BECs probed in different speckle realizations. As one diffuser rotates relative to the other around the common optical axis, we trace the optical speckle’s intensity cross-correlations and the quantum gas’ density cross-correlations. Our results show comparable outcomes for both measurement methods. The setup allows us to tune the disorder potential adapted to the characteristics of the quantum gas. These studies pave the way for investigating nonequilibrium physics in interacting quantum gases using controlled dynamical-disorder potentials.

Exciton dynamics from the mapping approach to surface hopping: comparison with Förster and Redfield theories.

We compare the recently introduced multi-state mapping approach to surface hopping (MASH) with the Förster and Redfield theories of excitation energy transfer. Whereas Förster theory relies on weak coupling between chromophores, and Redfield theory assumes the electronic excitations to be weakly coupled to fast chromophore vibrations, MASH is free from any perturbative or Markovian approximations. We illustrate this with an example application to the rate of energy transfer in a Frenkel-exciton dimer, showing that MASH interpolates correctly between the opposing regimes in which the Förster and Redfield results are reliable. We then compare the three methods for a realistic model of the Fenna-Matthews-Olson complex with a structured vibrational spectral density and static disorder in the excitation energies. In this case there are no exact results for comparison so we use MASH to assess the validity of Förster and Redfield theories. We find that Förster theory is the more accurate of the two on the picosecond timescale, as has been shown previously for a simpler model of this particular light-harvesting complex. We also explore various ways to sample the initial electronic state in MASH and find that they all give very similar results for exciton dynamics.

Temperature Dependent EXAFS to Address Functional Mechanisms in Battery Materials

Increasing the contribution of renewable energy sources is necessary to meet the fast increase of global energy needs and match the CO2 reduction targets. In order to address these challenges, intensive research efforts are ongoing both in energy harvesting and storage technologies such as solar panels, fuel cells, supercapacitors and batteries. The latter are required to match the energy demand and supply; in fact, batteries are by far the most ubiquitous energy storage technology currently employed.Synchrotron x-ray spectroscopies have played a key role in the continuous development and breakthroughs in battery science, thanks to their capability to provide accurate information on electronic structure of the redox active element, local structure, and morphological information. In particular, X-ray absorption spectroscopy (XAS) is more and more employed for addressing battery materials [1]. Generally, XAS studies on battery materials are performed at a single temperature as a function of charge, to access information on the electrochemical behavior and charge transfer mechanism during the intercalation or deintercalation process. However, the fact that the charging/discharging process is expected to have direct influence on the bond length characteristics, strength and disorder, it is important to perform temperature dependence measurements to find a realistic correlation between the local structure and the battery characteristics. Indeed, temperature-dependent studies quantitatively allow to discriminate in between static and dynamic disorder, and to have direct access to the local force constant between the atom pairs. Here the interest of performing temperature dependent extended X-ray absorption fine structure (EXAFS) studies is highlighted by exploiting several examples. In Li and Mn-rich NMC cathodes temperature-dependent EXAFS investigation revealed the evolution of the lattice rigidity which directly affects the reversible anionic redox contribution [2-3]. Similar studies on Ti based MXene-type [4], NaxCoO2 [5], and V2O5 [6] electrode materials underline the importance of the local atomic correlations as limiting factor in the ion diffusion in battery materials.

Microsecond Timescale Conformational Dynamics of a Small-Molecule Ligand within the Active Site of a Protein.

The possible internal dynamics of non-isotope-labeled small-molecule ligands inside a target protein is inherently difficult to capture. Whereas high crystallographic temperature factors can denote either static disorder or motion, even moieties with very low B-factors can be subject to vivid motion between symmetry-related sites. Here we report the experimental identification of internal μs timescale dynamics of a high-affinity, natural-abundance ligand tightly bound to the enzyme human carbonic anhydrase II (hCAII) even within a crystalline lattice. The rotamer jumps of the ligand's benzene group manifest themselves both, in solution and fast magic-angle spinning solid-state NMR 1 H R1ρ relaxation dispersion, for which we obtain further mechanistic insights from molecular-dynamics (MD) simulations. The experimental confirmation of rotameric jumps in bound ligands within proteins in solution or the crystalline state may improve understanding of host-guest interactions in biology and supra-molecular chemistry and may facilitate medicinal chemistry for future drug campaigns.

Konformationeller Austausch eines Liganden in der Bindetasche eines Proteins auf der Mikrosekundenzeitskala

AbstractDie experimentelle Erfassung möglicher interner Dynamik eines Liganden ohne Isotopenmarkierung im proteingebundenen Zustand ist grundsätzlich schwierig. Hohe Temperaturfaktoren aus Kristallstrukturen können statische Heterogenität nicht von Bewegung unterscheiden, zudem können für symmetrische Bewegungen selbst bei niedrigsten B‐Faktoren schnelle Bewegungen vorhanden sein. Hier zeigen wir die sowohl in Lösung als auch im Kristall experimentell beobachtete interne μs‐Dynamik eines nicht‐isotopenmarkierten Liganden, während dieser mit hoher Affinität an das Enzym humane Carboanhydrase II (hCAII) gebunden ist. Der sprunghafte Wechsel zwischen den Rotameren der Benzolgruppe des Liganden verursacht sowohl in Lösungs‐ als auch Festkörper NMR mit schneller Rotation um den magischen Winkel 1H R1ρ Relaxationsdispersion, für die mittels Molecular Dynamics (MD)‐Simulationen mechanistische Einblicke erhalten werden. Die experimentelle Erfassung von konformationellem Austausch in gebundenen Liganden in Lösung und im Festkörper könnte einem besseren Verständnis von Wirt‐Gast‐Interaktionen in Biologie und supramolekularer und medizinischer Chemie dienen.

Effect of High-Pressure Torsion on Phase Formation and Mechanical Properties of a High-Entropy TiZrHfMoCrCo Alloy.

This investigation delved into the alterations in the mechanical properties of a TiZrHfMoCrCo high-entropy alloy due to phase transformations induced by high-pressure torsion (HPT). The alloy's genesis involved levitation melting within an argon atmosphere, presenting two distinct states for analysis: the initial, post-manufacturing state and the state subsequent to HPT treatment. The original alloy featured a composition comprising a singular A2 phase with a bcc lattice and two Laves phases, C15 and C14. The HPT process triggered significant phase modifications: a retention of one C15 Laves phase and decomposition of the bcc phase into two distinct phases exhibiting different bcc lattice parameters. The HPT-induced effect prominently manifests as strong grain refinement. However, scanning electron microscopy (SEM) observations unveiled persistent inhomogeneities at a micron scale both before and after HPT treatment. Thus, grain refinement occurs separately within each of the bcc and Laves phases, visible in the light, dark, and gray areas in SEM images, while mixing does not occur on the scale of several microns. The examination of Ti, Cr, Co, Zr, Mo, and Hf via X-ray absorption spectroscopy (EXAFS) at specific K-edges and L3-edge revealed that the HPT treatment conserves the local atomic environment of metal atoms, albeit with a slight elevation in static disorder. Assessments through microhardness and three-point bending tests demonstrated the material's inherent hardness and brittleness. The microhardness, standing at a substantial value of 600 HV, displayed negligible augmentation post-HPT. However, the microhardness of individual phases exhibited a notable alteration, nearly doubling in magnitude.

Is there a relationship between static postural control and core stability? A cross-sectional study in soccer players with groin pain

BackgroundStatic postural control disorders have been documented in soccer players suffering from groin pain (GP). Understanding the mechanisms of these disorders is crucial in designing rehabilitation programs. ObjectivesTo (i) assess static postural control and core stability in soccer players suffering from GP compared to their peers and (ii) explore the relationship between these two parameters. MethodsThis cross-sectional study involved 42 male soccer players suffering from GP (GP group: GPG) and 42 healthy players (control group: CG). Static postural control (stabilometric platform) and core stability (core endurance tests) were assessed. ResultsCenter of pressure velocity in the GPG was significantly higher compared to the CG during bipedal stance on the firm surface with eyes closed (2.66 [95 % CI: 0.86–3.67]; p < 0.01) and on the foam one (p < 0.001) in both conditions; eyes opened (2.88 [95 % CI: 1.42–4.43]) and closed (5.88 [95 % CI: 2.66–9.10]), and on the IL in eyes closed (12.54 [95 % CI: 4.27–20.80]; p < 0.01). Besides, GPG revealed significant (p < 0.001) lower core stability measures compared to CG. No significant associations (p > 0.05) were observed between static postural control and core stability in GPG. ConclusionSoccer players suffering from GP showed static disorders of postural control compared with their peers. These impairments were not associated with measures of core stability. These findings provide insight into the direction of future research exploring the mechanisms underlying deficits in static postural control in soccer players suffering from GP.

Many-Exciton Quantum Dynamics in a Ruddlesden-Popper Tin Iodide.

We present a study on the many-body exciton interactions in a Ruddlesden-Popper tin halide, namely, (PEA)2SnI4 (PEA = phenylethylammonium), using coherent two-dimensional electronic spectroscopy. The optical dephasing times of the third-order polarization observed in these systems are determined by exciton many-body interactions and lattice fluctuations. We investigate the excitation-induced dephasing (EID) and observe a significant reduction of the dephasing time with increasing excitation density as compared to its lead counterpart (PEA)2PbI4, which we have previously reported in a separate publication [J. Chem. Phys.2020, 153, 164706]. Surprisingly, we find that the EID interaction parameter is four orders of magnitude higher in (PEA)2SnI4 than that in (PEA)2PbI4. This increase in the EID rate may be due to exciton localization arising from a more statically disordered lattice in the tin derivative. This is supported by the observation of multiple closely spaced exciton states and the broadening of the linewidth with increasing population time (spectral diffusion), which suggests a static disordered structure relative to the highly dynamic lead-halide. Additionally, we find that the exciton nonlinear coherent lineshape shows evidence of a biexcitonic state with low binding energy (<10 meV) not observed in the lead system. We model the lineshapes based on a stochastic scattering theory that accounts for the interaction with a nonstationary population of dark background excitations. Our study provides evidence of differences in the exciton quantum dynamics between tin- and lead-based Ruddlesden-Popper metal halides (RPMHs) and links them to the exciton-exciton interaction strength and the static disorder aspect of the crystalline structure.

Multistate Reaction Coordinate Model for Charge and Energy Transfer Dynamics in the Condensed Phase.

Constructing multistate model Hamiltonians from all-atom electronic structure calculations and molecular dynamics simulations is crucial for understanding charge and energy transfer dynamics in complex condensed phases. The most popular two-level system model is the spin-boson Hamiltonian, where the nuclear degrees of freedom are represented as shifted normal modes. Recently, we proposed the general multistate nontrivial extension of the spin-boson model, i.e., the multistate harmonic (MSH) model, which is constructed by extending the spatial dimensions of each nuclear mode so as to satisfy the all-atom reorganization energy restrictions for all pairs of electronic states. In this work, we propose the multistate reaction coordinate (MRC) model with a primary reaction coordinate and secondary bath modes as in the Caldeira-Leggett form but in extended spatial dimensions. The MRC model is proven to be equivalent to the MSH model and offers an intuitive physical picture of the nuclear-electronic feedback in nonadiabatic processes such as the inherent trajectory of the reaction coordinate. The reaction coordinate is represented in extended dimensions, carrying the entire reorganization energies and bilinearly coupled to the secondary bath modes. We demonstrate the MRC model construction for photoinduced charge transfer in an organic photovoltaic caroteniod-porphyrin-C60 molecular triad dissolved in tetrahydrofuran as well as excitation energy transfer in a photosynthetic light-harvesting Fenna-Matthews-Olson complex. The MRC model provides an effective and robust platform for investigating quantum dissipative dynamics in complex condensed-phase systems since it allows a consistent description of realistic spectral density, state-dependent system-bath couplings, and heterogeneous environments due to static disorder in reorganization energies.

THE INFLUENCE OF PHYSICAL THERAPY ON INDICATORS OF LOCOMOTIVE SYNDROME IN ELDERLY PERSONS WITH OSTEOARTHRITIS OF THE KNEE AND OBESITY

Aim: to assess the effectiveness of the developed physical therapy program on locomotive syndrome parameters in elderly people with osteoarthritis of the knee and obesity.&#x0D; Material and methods. 93 elderly people were examined. The control group consisted of 31 people without osteoarthritis of the joints, with no obesity. The main group 1 consisted of 33 people who received rehabilitation according to the general principles of osteoarthritis correction. Representatives of the main group 2 (31 people) were engaged in a physical therapy program using functional training on the «Prosedos» platform, therapeutic exercises, Proprioceptive Neuromuscular Facilitation; massage, kinesiological taping, nutritional correction, patient education. The effectiveness of the program was evaluated according to the dynamics of the Short Physical Performance Battery, Functional Gait Assessment, Tinetti-test (Performance-Oriented Mobility Assessment), 25-question Geriatric Locomotive Function Scale.&#x0D; Results. Elderly patients with osteoarthritis of the knee and obesity were found to have impaired balance (Short Physical Performance Battery), altered gait stereotype (Functional Gait Assessment), risk of falling when performing activities of daily living (Tinetti-test) at the level of locomotive syndrome II degree (25- question Geriatric Locomotive Function Scale). The developed program of physical therapy in persons of the main group 2 revealed a statistically significantly better effect on the components of the locomotive syndrome compared to the initial examination in all studied parameters (p&lt;0.05). Elderly patients who underwent rehabilitation according to the standard program for the correction of osteoarthritis achieved a statistically significant improvement compared to the initial state according to the studied parameters (p&lt;0.05), but less pronounced compared to the tested program.&#x0D; Conclusions. Elderly patients with osteoarthritis of the knee joints and obesity need to develop physical therapy programs taking into account and correcting the specifics of each condition, the presence of static and dynamic balance disorders and the risk of falling, which will increase the overall effectiveness of rehabilitation measures.