Nonadiabatic Dynamics: A Semiclassical Approach

Nonadiabatic dynamics has been an essential part of quantum chemistry since the 1930’s. Nonadiabatic effects play a crucial role in photo-physical and photo-chemical reactions for both small and large molecules in both gas and condensed phases. Modeling dynamics of photoinduced reactions has been a new frontier of chemistry. Many dynamical phenomena, such as intersystem crossing, non-radiative relaxation, and charge energy transfer, require a nonadiabatic description which incorporates transitions between electronic states. In Chapter 2, the property of scattering region in the semiclassical limit is investigated. We suggest that a nuclear wavepacket close enough to the conical intersection will propagate ballistically in a straight line through the scattering region with distance λ+, the impact parameter, away from the conical intersection. Upon taking the semiclassical limit, we have proven that in a certain neighborhood of the conical intersection, the adiabatic propagation and ballistic propagation are both valid. The resulted complete propagator is governed by the semiclassical propagation along the reference path which connects the initial and final points, and an integration over the impact parameter, hence only depends on the initial and final classical states of the system. In Chapter 3, we identify the main differences between the effects of Kramers symmetry on the systems with even and odd number of electrons, the ways how the aforementioned symmetry affects the structure of the Conical Seams (CSs), and how it shows up in semiclassical propagation of nuclear wavepackets, crossing the CSs. We identify the topological invariants, associated with CSs, in three cases: even and odd number of electrons with time-reversal symmetry, as well as absence of the latter. We obtain asymptotically exact semiclassical analytical solutions for wavepackets scattered on a CS for all three cases, identify topological features in a non-trivial shape of the scattered wavepacket, and connect them to the topological invariants, associated with CSs. We argue that, due to robustness of topology, the non-trivial wavepacket structure is a topologically protected evidence of a wavepacket having passed through a CS, rather than a feature of a semiclassical approximation. In Chapter 4, we present, in detail, an algorithm based on Monte-Carlo sampling of the semiclassical time-dependent wavefunction, that involves running simple surface hopping dynamics, followed by a post-processing step which adds little cost. The method requires only a few quantities from quantum chemistry calculations, can systematically be improved, and provides excellent agreement with exact quantum mechanical results. Here we show excellent agreement with exact solutions for scattering results of standard test problems. Additionally, we find that convergence of the wavefunction is controlled by complex valued phase factors, the size of the nonadiabatic coupling region, and the choice of sampling function. These results help in determining the range of applicability of the method, and provide a starting point for further improvement

The Characteristics of Molière’s Comedy Writing —Centred on Harpagon’s Characterisation

The works of the French classical comedian Molière are of exceptional value. In his satirical comedies, Molière often creates sensible, vivid, contemporary, and real characters through descriptions of detailed behavior and the setting of coincident and conflicts. Harpagon, for instance, has become a global synonym for miserliness due to Molière’s extreme focus on this single character trait. Critics of his time labeled Harpagon as a “flat character”, yet it is precisely this “flatness” that makes the character memorable. Molière possessed a serious spirit of realism and a democratic tendency, using comedy as a means to educate the public. Through characters like Harpagon, he exposed the bourgeoisie’s cruelty, hypocrisy, and greedy exploitation of the lower class, delivering sharp and pungent satire. Molière’s ability to craft such characters not only entertained but also conveyed powerful social critiques, solidifying his importance in literary and social history

Complete Mitogenome sequencing of the fish louse Argulus japonicus (Crustacea: Branchiura): Comparative analyses and phylogenetic implications

The fish louse Argulus japonicus, a branchiuran crustacean of the Argulidae family, is attracting increasing attention because of its parasitic tendencies and significant health threats to global fish farming. The mitogenomes can yield a foundation for studying epidemiology, genetic diversity, and molecular ecology and therefore may be used to assist in the surveillance and control of A. japonicus. In this study, we sequenced and assembled the complete mitogenome of A. japonicus to shed light on its genetic and evolutionary blueprint. Our investigation indicated that the 15,045-bp circular genome of A. japonicus encodes 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), and 2 ribosomal RNAs (rRNAs) with significant AT and GC skews. Comparative genomics provided an evolutionary scenario for the genetic diversity of 13 PCGs: all were under purifying selection, with cox1 and nad6 having the lowest and highest evolutionary rates, respectively. Genome-wide phylogenetic trees established a close relationship between species of the families Argulidae (Arguloida) and Armilliferidae (Porocephalida) within Crustacea, and further, A. japonicus and Argulus americanus were determined to be more closely related to each other than to others within the family Argulidae. Single PCG-based phylogenies supported nad1 and nad6 as the best genetic markers for evolutionary and phylogenetic studies for branchiuran crustaceans due to their similar phylogenetic topologies with those of genome-based phylogenetic analyses. To sum up, these comprehensive mitogenomic data of A. japonicus and related species refine valuable marker resources and should contribute to molecular diagnostic methods, epidemiological investigations, and ecological studies of the fish ectoparasites in Crustacea

Tunable Interband Transitions in Twisted h-BN/Graphene Heterostructures

In twisted h-BN/graphene heterostructures, the complex electronic properties of the fast-traveling electron gas in graphene are usually considered to be fully revealed. However, the randomly twisted heterostructures may also have unexpected transition behaviors, which may influence the device performance. Here, we study the twist angle-dependent coupling effects of h-BN/graphene heterostructures using monochromatic electron energy loss spectroscopy. We find that the moir\'e potentials alter the band structure of graphene, resulting in a redshift of the intralayer transition at the M-point, which becomes more pronounced up to 0.25 eV with increasing twist angle. Furthermore, the twisting of the Brillouin zone of h-BN relative to the graphene M-point leads to tunable vertical transition energies in the range of 5.1-5.6 eV. Our findings indicate that twist-coupling effects of van der Waals heterostructures should be carefully considered in device fabrications, and the continuously tunable interband transitions through the twist angle can serve as a new degree of freedom to design optoelectrical devices

Palliative care patients’ attitudes and openness towards psilocybin-assisted psychotherapy for existential distress

IntroductionPatients with incurable illnesses often experience existential distress, profoundly impacting their well-being. Current medical approaches have limitations in addressing these burdens. Psilocybin, a promising psychedelic compound, may offer therapeutic benefits. This pilot survey study aimed to investigate the attitudes and openness toward psilocybin-assisted psychotherapy (PAT) among patients with incurable illnesses. The objective is to assess patients’ attitudes toward PAT and identify potential barriers and concerns, including exploring the association between beliefs in psilocybin’s therapeutic benefits and interest in receiving this treatment.MethodsThe survey study was conducted at the Tampa General Hospital Palliative Care Outpatient office in the United States. Participants were 32 English-fluent patients, aged 18 or older, with incurable illnesses. The survey included demographic questions, a validated tool to measure existential distress, and questions about knowledge and concerns regarding psilocybin. Attitudes toward PAT and interest in its future use were assessed using Likert scale responses.ResultsAmong the 31 analyzed participants, 51.6% expressed interest in future psilocybin treatment, while 32.3% did not indicate interest. Belief in the psilocybin’s therapeutic benefits for stress and anxiety significantly correlated with interest in use. Concerns included risk of psychosis, lack of trained providers, and potential for exploitation. No demographic factors were associated with interest or levels of distress.ConclusionsThis pilot study provides insights into the attitudes and concerns toward PAT among patients with incurable illnesses. Over half of participants expressed interest. However, concerns regarding its use were identified, with patients’ concern for the risk of exploitation associated with PAT as an especially novel concern documented in this patient population. This highlighted the need for further education of risks and benefits or PAT by trained clinicians and rigorous training of clinicians with the establishment of safeguards against exploitation. Further research is necessary to explore the potential benefits of PAT and related non-psilocybin psychedelic compounds in addressing existential distress among patients with incurable illnesses

Locally advanced rectal cancer with dMMR/MSI-H may be excused from surgery after neoadjuvant anti-PD-1 monotherapy: a multiple-center, cohort study

ObjectiveExamine patients with locally advanced rectal cancer (LARC) with deficient mismatch repair (dMMR) or microsatellite instability-high (MSI-H) who received neoadjuvant immunotherapy (nIT), and compare the outcomes of those who chose a watch-and-wait (WW) approach after achieving clinical complete response (cCR) or near-cCR with those who underwent surgery and were confirmed as pathological complete response (pCR).MethodsLARC patients with dMMR/MSI-H who received nIT were retrospectively examined. The endpoints were 2-year overall survival (OS), 2-year disease-free survival (DFS), local recurrence (LR), and distant metastasis (DM). The efficacy of programmed cell death protein-1 (PD-1) inhibitor, immune-related adverse events (irAEs), surgery-related adverse events (srAEs), and enterostomy were also recorded.ResultsTwenty patients who received a PD-1 inhibitor as initial nIT were examined. Eighteen patients (90%) achieved complete response (CR) after a median of 7 nIT cycles, including 11 with pCR after surgery (pCR group), and 7 chose a WW strategy after evaluation as cCR or near-cCR (WW group). Both groups had median follow-up times of 25.0 months. Neither group had a case of LR or DM, and the 2-year DFS and OS in each group was 100%. The two groups had similar incidences of irAEs (P=0.627). In the pCR group, however, 2 patients (18.2%) had permanent colostomy, 3 (27.3%) had temporary ileostomy, and 2 (18.2%) had srAEs.ConclusionNeoadjuvant PD-1 blockade had high efficacy and led to a high rate of CR in LARC patients with dMMR/MSI-H. A WW strategy appears to be a safe and reliable option for these patients who achieve cCR or near-cCR after nIT

Improving cooperation in peer-to-peer systems using social networks

Rational and selfish nodes in P2P systems usually lack effective incentives to cooperate, contributing to the increase of free-riders, and degrading the system performance. Various attacks such as whitewashing, collusion, and software cracking pose great challenges on distributed reputation management. To tackle these problems, we propose to build a social network on P2P system, and use the strength of social connections to facilitate transactions in P2P system. The ’ small world’ character of social networks makes it feasible for nodes to locate resources and conduct transactions while maintain limited local memory history. Such distributed memory combined by relationship between peers • constructs a powerful reputation management network, which could have better performance than shared history system and is more robust under various attacks. Our simulation and analysis show that the social network model can greatly incent cooperation in P2P networks and enormously reduce the memory cost. 1