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This research examines the nonadiabatic dynamics of cyclobutanone after excitation into the n → 3s Rydberg S2 state. It stems from our contribution to the Special Topic of the Journal of Chemical Physics to test the predictive capability of computational chemistry against unseen experimental data. Decoherence-corrected fewest-switches surface hopping was used to simulate nonadiabatic dynamics with full and approximated nonadiabatic couplings. Several simulation sets were computed with different electronic structure methods, including a multiconfigurational wavefunction [multiconfigurational self-consistent field (MCSCF)] specially built to describe dissociative channels, multireference semiempirical approach, time-dependent density functional theory, algebraic diagrammatic construction, and coupled cluster. MCSCF dynamics predicts a slow deactivation of the S2 state (10 ps), followed by an ultrafast population transfer from S1 to S0 (<100 fs). CO elimination (C3 channel) dominates over C2H4 formation (C2 channel). These findings radically differ from the other methods, which predicted S2 lifetimes 10–250 times shorter and C2 channel predominance. These results suggest that routine electronic structure methods may hold low predictive power for the outcome of nonadiabatic dynamics. [ABSTRACT FROM AUTHOR]

The onset of malaria causes the induction of various inflammatory markers in the host's body, which in turn affect the body's homeostasis and create several cerebral complications. Polarization of myeloid-derived suppressor cells (MDSCs) from the classically activated M1 to alternatively activated M2 phenotype increases the secretion of pro-inflammatory molecules. Treatment with recombinant IL-33 (rIL-33) not only alters this MDSC's polarization but also targets the glycolysis pathway of the metabolism in MDSCs, rendering them less immunosuppressive. Along with that, the Helper T-cells subset 17 (Th17)/T regulatory cells (Tregs) ratio is skewed towards Th17, which increases inflammation by producing more IL-17. However, treating with rIL-33 also helps to restore this ratio, which brings back homeostasis. During malaria infection, there is an upregulation of IL-12 production from dendritic cells along with a distorted myeloid dendritic cells (mDC)/plasmacytoid dendritic cells (pDC) ratio towards mDCs promoting inflammation. Administering rIL-33 will also subvert this IL-12 production and increase the population of pDC in the host's immune system during malaria infection, thus restoring mDC/pDC to homeostasis. Therefore, treatment with rIL-33 to reduce the pro-inflammatory signatures and maintenance of immune homeostasis along with the increase in survivability could be a potential therapeutic approach for cerebral malaria. [ABSTRACT FROM AUTHOR]

Fast and reliable detection of patients with severe and heterogeneous illnesses is a major goal of precision medicine.sup.1,2. Patients with leukaemia can be identified using machine learning on the basis of their blood transcriptomes.sup.3. However, there is an increasing divide between what is technically possible and what is allowed, because of privacy legislation.sup.4,5. Here, to facilitate the integration of any medical data from any data owner worldwide without violating privacy laws, we introduce Swarm Learning--a decentralized machine-learning approach that unites edge computing, blockchain-based peer-to-peer networking and coordination while maintaining confidentiality without the need for a central coordinator, thereby going beyond federated learning. To illustrate the feasibility of using Swarm Learning to develop disease classifiers using distributed data, we chose four use cases of heterogeneous diseases (COVID-19, tuberculosis, leukaemia and lung pathologies). With more than 16,400 blood transcriptomes derived from 127 clinical studies with non-uniform distributions of cases and controls and substantial study biases, as well as more than 95,000 chest X-ray images, we show that Swarm Learning classifiers outperform those developed at individual sites. In addition, Swarm Learning completely fulfils local confidentiality regulations by design. We believe that this approach will notably accelerate the introduction of precision medicine. Swarm Learning is a decentralized machine learning approach that outperforms classifiers developed at individual sites for COVID-19 and other diseases while preserving confidentiality and privacy., Author(s): Stefanie Warnat-Herresthal [sup.1] [sup.2] , Hartmut Schultze [sup.3] , Krishnaprasad Lingadahalli Shastry [sup.3] , Sathyanarayanan Manamohan [sup.3] , Saikat Mukherjee [sup.3] , Vishesh Garg [sup.3] [sup.4] , Ravi Sarveswara [...]

Pyrene fluorescence after a high-energy electronic excitation exhibits a prominent band shoulder not present after excitation at low energies. The standard assignment of this shoulder as a non-Kasha emission from the second-excited state (S2) has been recently questioned. To elucidate this issue, we simulated the fluorescence of pyrene using two different theoretical approaches based on vertical convolution and nonadiabatic dynamics with nuclear ensembles. To conduct the necessary nonadiabatic dynamics simulations with high-lying electronic states and deal with fluorescence timescales of about 100 ns of this large molecule, we developed new computational protocols. The results from both approaches confirm that the band shoulder is, in fact, due to S2 emission. We show that the non-Kasha behavior is a dynamic-equilibrium effect not caused by a metastable S2 minimum. However, it requires considerable vibrational energy, which can only be achieved in collisionless regimes after transitions into highly excited states. This strict condition explains why the S2 emission was not observed in some experiments. [ABSTRACT FROM AUTHOR]

Myeloid-Derived Suppressor Cells (MDSCs), also known as 'Natural Suppressor Cells (NSCs)', 'Immature Myeloid Cells, (IMCs), or 'Myeloid Suppressor Cells' (MSCs), are renowned for suppressing the immune functioning of T lymphocytes. Depending on the structural similarity with neutrophils and monocytes, MDSCs can be classified as polymorphonuclear MDSCs (PMN-MDSCs) and monocytic MDSCs (M-MDSCs). On the other hand, T cells, generally subdivided into CD4+ and CD8+ groups based on the surface glycoprotein, are crucial for generating an adaptive immune response. During the event of an infection, MDSCs and T cells, along with other immune regulatory cells, interplay and generate a robust host immune response against the invading pathogens. In this review, we have highlighted the role of MDSCs and different subsets of CD4+ T cells, such as Th1, Th2, Th17, Th9, Th22, Treg, Tfh, and Tr1 with and various transcription factors associated with them, in different well known bacterial, viral, parasitic and fungal diseases. Changes in the MDSC population were found to be associated with either promotion or suppression of T cell subsets in different infections. The relative frequency and absolute numbers of MDSCs in the peripheral blood, therefore, may serve as an important marker useful in future immunotherapeutics. [ABSTRACT FROM AUTHOR]

Excited states relaxation in complex molecules often involves two types of nonradiative transitions, internal conversion (IC) and intersystem crossing (ISC). In the situations when the timescales of IC and ISC are comparable, an interplay between these two types of transitions can lead to complex nonadiabatic dynamics on multiple electronic states of different characters and spin multiplicities. We demonstrate that the generalized ab initio multiple spawning (GAIMS) method interfaced with the fast graphics processing unit-based TeraChem electronic structure code can be used to model such nonadiabatic dynamics involving both the IC and ISC transitions in molecules of moderate size. We carried out 1500 fs GAIMS simulations leading to the creation of up to 2500 trajectory basis functions to study the excited states relaxation in 2-cyclopentenone. After a vertical excitation from the ground state to the bright S2 state, the molecule quickly relaxes to the S1 state via conical intersection. The following relaxation proceeds along two competing pathways: one involves IC to the ground state, and the other is dominated by ISC to the low-lying triplet states. The time constants describing the population transfer between the six lowest singlet and triplet states predicted by the GAIMS dynamics are in good agreement with the characteristic times of IC and ISC obtained from the analysis of the time-resolved photoelectron spectrum. [ABSTRACT FROM AUTHOR]

This work aims to elucidate the dependence of the excited-state lifetime of adenine and adenosine on temperature. So far, it has been experimentally shown that while adenine's lifetime is unaffected by temperature, adenosine's lifetime strongly depends on it. However, the non-Arrhenius temperature dependence has posed a challenge in explaining this phenomenon. We used surface hopping to simulate the dynamics of adenine and adenosine in the gas phase at 0 and 400 K. The temperature effects were observed under the initial conditions via Wigner sampling with thermal corrections. Our results confirm that adenine's excited-state lifetime does not depend on temperature, while adenosine's lifetime does. Adenosine's dependency is due to intramolecular vibrational energy transfer from adenine to the ribose group. At 0 K, this transfer reduced the mean kinetic energy of adenine's moiety so much that internal conversion is inhibited, and the lifetime elongated by a factor of 2.3 compared to that at 400 K. The modeling also definitively ruled out the influence of viscosity, which was proposed as an alternative explanation previously. [ABSTRACT FROM AUTHOR]

This work applies theoretical and computational methods to investigate the relationship between phosphorescence lifetime and the electronic character of the lowest triplet state of aromatic carbonyls. A formal analysis of the spin-perturbed wave functions shows that phosphorescence is due to a direct spin–orbit coupling mechanism modulated by permanent dipoles when the T1 minimum is 3nπ*. If the minimum is a totally symmetric 3ππ*, phosphorescence is due to an indirect spin–orbit coupling mechanism involving transition dipole moments with other excited states. The magnitude difference between permanent and transition dipoles leads to a much faster 3nπ* phosphoresce than 3ππ*. These predictions were verified with phosphorescence lifetime simulations of benzaldehyde and its three derivatives in the gas phase employing a vertical approximation and the nuclear ensemble approaches. Both predict 3nπ* emission within a few tens of milliseconds. While the vertical approach indicates a 3ππ* emission within a few seconds, vibronic corrections bring this value down to about 200 ms. [ABSTRACT FROM AUTHOR]

Norm retrieval was introduced for Hilbert space frames for the first time by Bahmanpour et. al. in the year 2015. In order for a subspace as well as its orthogonal complement to do norm retrieval, it was proved by Bahmanpour et. al. that norm retrieval is a necessary requirement. Basically, norm retrieval refers to the process of reconstructing the signal's norm from the intensity measurements. We give a few characterizations for norm retrieval by vectors and subspaces under the action of bounded linear operators. [ABSTRACT FROM AUTHOR]

Norm retrieval was introduced for Hilbert space frames for the first time by Bahmanpour et. al. in the year 2015. In order for a subspace as well as its orthogonal complement to do norm retrieval, it was proved by Bahmanpour et. al. that norm retrieval is a necessary requirement. Basically, norm retrieval refers to the process of reconstructing the signal's norm from the intensity measurements. We give a few characterizations for norm retrieval by vectors and subspaces under the action of bounded linear operators. [ABSTRACT FROM AUTHOR]

While theoretical estimates suggest that cavitation of water should occur when pressure falls much below −25 MPa at room temperature, in experiments, we commonly observe conversion to vapor at pressures of the order of 3 kPa. The commonly accepted explanation for this discrepancy is that water usually contains nanometer-sized cavitation nuclei. When the pressure decreases, these nuclei expand and become visible to the naked eye. However, the origin of these cavitation nuclei is not well understood. An earlier work in this field has mainly focused on the inception of nuclei which are purely composed of water vapor, whereas experimental data suggest that these nuclei are mainly composed of air. In this Letter, we develop a theoretical approach to study the inception of cavitation nuclei in water with uniformly dissolved air, using a diffuse interface approach. We derive equations which govern the transition of water with uniformly dissolved air to a critical state. Our results show that the dissolved air decreases the free energy barrier from the initial to the critical state, thereby aiding the formation of cavitation nuclei. This study opens up possibilities to explore cavitation inception in fluids containing dissolved gases. [ABSTRACT FROM AUTHOR]

Paradigms basically are a distinct set of concepts or thoughts patterns, including theories, research methods, postulates and standards for what constitute legitimate contributions to a field. Or, it can be also defined as a set of theories and assumptions that comprises a worldview, or developed framework that informs action. There are four paradigms observed so far in the field of agricultural extension in India. These paradigms were prevalent in the colonial times, and then again it reappeared in the 1970s when the Training and Visit system was established across Asia. These are Technology Transfer which was persuasive and paternalistic in nature, key features were delivering specific recommendations from research using to-down and persuasive methods to increase agricultural production. Related models and approaches were mostly conventional in nature. Then a shift was observed towards advisory work with persuasive and participatory mode of extension delivery system. Responding to specific farmer inquiries about particular problem, using problem solving or persuasive methods. Models and approaches introduced related to this paradigm are commodity-based system, market-oriented extension, agribusiness extension. Next shift was towards human resource development or non-formal education with educational and paternalistic views. Training farmers and rural people, and helping farmers to organize into self-help learning groups were the key feature of this paradigm by introducing farmer-field schools and university-based extension models. The latest shift was observed towards facilitation for empowerment with educational and participatory mode of delivery. Key features of this shift encourage facilitating horizontal communication, active/collaborative/social learning, co-construction of knowledge, collective action, empowerment processes among farmers and rural people, working with groups to help them address specific issues. Participatory extension, farming systems research and extension, farmer first related models and approaches were including participatory learning and action, participatory technology development, farmer-led extension, farmer-field schools, farmer networks, study circles, facilitation of local processes, local development, and agro-ecological extension. From discussion mentioned in the study, it can understand that each of the paradigms added new insights to the extension delivery system which was mainly related to rural development and then gradually evolved in to a robust system to facilitation for empowerment to bring a sustainable development process. [ABSTRACT FROM AUTHOR]

Biofilm formation is an important and ubiquitous mode of growth among bacteria. Central to the evolutionary advantage of biofilm formation is cell-cell and cell-surface adhesion achieved by a variety of factors, some of which are diffusible compounds that may operate as classical public goods--factors that are costly to produce but may benefit other cells. An outstanding question is how diffusible matrix production, in general, can be stable over evolutionary timescales. In this work, using Vibrio cholerae as a model, we show that shared diffusible biofilm matrix proteins are indeed susceptible to cheater exploitation and that the evolutionary stability of producing these matrix components fundamentally depends on biofilm spatial structure, intrinsic sharing mechanisms of these components, and flow conditions in the environment. We further show that exploitation of diffusible adhesion proteins is localized within a well-defined spatial range around cell clusters that produce them. Based on this exploitation range and the spatial distribution of cell clusters, we constructed a model of costly diffusible matrix production and related these length scales to the relatedness coefficient in social evolution theory. Our results show that production of diffusible biofilm matrix components is evolutionarily stable under conditions consistent with natural biofilm habitats and host environments. We expect the mechanisms revealed in this study to be relevant to other secreted factors that operate as cooperative public goods in bacterial communities and the concept of exploitation range and the associated analysis tools to be generally applicable. [ABSTRACT FROM AUTHOR]