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Developing a new class of molecular heaters to be applied in plants is a new strategy to extend locations suitable for agriculture to higher altitudes, preventing damages caused by the cold. The underlining idea is that molecular heaters are able to absorb UV-vis radiation and convert it into heat, in this case, to the leaves' surface. Inspired by nature and its efficient photoprotective features, we study derivatives of sinapoyl malate (SM). These derivatives exhibit a fast and efficient nonradiative decay. Their relaxation mechanisms involve a twist around their ethylenic-like double bond to generate a dark twisted charge transfer state, reaching a twisted conical intersection between S1/S0 states. These molecules were also investigated in a different medium to understand the effect of the environment in their photophysics. Another class of potential candidates as molecular heaters are the diketopyrrolopyrroles due to their photostability and strong visible light absorption. Moreover, it was recently shown that nonradiative pathways dominate the photophysics of some dimer derivatives. Here, we show that the dimer has a low-lying doubly excited state that is not energetically accessible to the monomer, and this delays the fluorescence allowing internal conversion to occur first. We characterize the doubly excited state wavefunction by systematically changing the derivatives to tune the \(\pi\)-scaffold size and the acceptor and donor characters. This analysis opens new ways to control the balance between luminescence and internal conversion in such systems. However, a proper characterization of doubly excited states is still a challenge, and no rigorous and transferable classification scheme between methods exists. Then, we propose classifying doubly excited states according to two limiting cases: the open- and closed-shell doubly excited states (DOS and DCS, respectively). We propose a classification scheme based on descriptors extracted from density matrices. As an example of DOS, we discuss formaldehyde dimer. On the other hand, DCS was more elusive. An investigation of butadiene and longer polyenes shows that none yields the idealized case. Additionally, we test the consistency of our classification scheme within ADC(3), MRCI and DFT/MRCI descriptions, in which most variation is due to the amount of static correlation.

International audience; In the Baeck-An (BA) approximation, first-order nonadiabatic coupling vectors are given in terms of adiabatic energy gaps and the second derivative of the gaps with respect to the coupling coordinate. In this paper, a time-dependent (TD) BA approximation is derived, where the couplings are computed from the energy gaps and their second timederivatives. TD-BA couplings can be directly used in fewest switches surface hopping, enabling nonadiabatic dynamics with any electronic structure methods able to provide excitation energies and energy gradients. Test results of surface hopping with TD-BA couplings for ethylene and fulvene show that the TD-BA approximation delivers a qualitatively correct picture of the dynamics and a semiquantitative agreement with reference data computed with exact couplings. Nevertheless, TD-BA does not perform well in situations conjugating strong couplings and small velocities. Considered the uncertainties in the method, TD-BA couplings could be a competitive approach for inexpensive, exploratory dynamics with a small trajectories ensemble. We also assessed the potential use of TD-BA couplings for surface hopping dynamics with time-dependent density functional theory (TDDFT), but the results are not encouraging due to singlet instabilities near the crossing seam with the ground state.

Background Influenza illness burden is substantial, particularly among young children, older adults, and those with underlying conditions. Initiatives are underway to develop better global estimates for influenza-associated hospitalizations and deaths. Knowledge gaps remain regarding the role of influenza viruses in severe respiratory disease and hospitalizations among adults, particularly in lower-income settings. Methods and findings We aggregated published data from a systematic review and unpublished data from surveillance platforms to generate global meta-analytic estimates for the proportion of acute respiratory hospitalizations associated with influenza viruses among adults. We searched 9 online databases (Medline, Embase, CINAHL, Cochrane Library, Scopus, Global Health, LILACS, WHOLIS, and CNKI; 1 January 1996–31 December 2016) to identify observational studies of influenza-associated hospitalizations in adults, and assessed eligible papers for bias using a simplified Newcastle–Ottawa scale for observational data. We applied meta-analytic proportions to global estimates of lower respiratory infections (LRIs) and hospitalizations from the Global Burden of Disease study in adults ≥20 years and by age groups (20–64 years and ≥65 years) to obtain the number of influenza-associated LRI episodes and hospitalizations for 2016. Data from 63 sources showed that influenza was associated with 14.1% (95% CI 12.1%–16.5%) of acute respiratory hospitalizations among all adults, with no significant differences by age group. The 63 data sources represent published observational studies (n = 28) and unpublished surveillance data (n = 35), from all World Health Organization regions (Africa, n = 8; Americas, n = 11; Eastern Mediterranean, n = 7; Europe, n = 8; Southeast Asia, n = 11; Western Pacific, n = 18). Data quality for published data sources was predominantly moderate or high (75%, n = 56/75). We estimate 32,126,000 (95% CI 20,484,000–46,129,000) influenza-associated LRI episodes and 5,678,000 (95% CI 3,205,000–9,432,000) LRI hospitalizations occur each year among adults. While adults, In this meta-analysis, Kathryn E. Lafond and colleagues estimate the global hospitalisation burden from influenza infections in adults., Author summary Why was this study done? Every year, millions of people become infected with influenza viruses, which infect the airways and cause symptoms that include a fever, tiredness and weakness, general aches and pains, sore throat, and cough. Most infected individuals recover quickly, but some develop more severe illness such as pneumonia, and may require hospitalization. Influenza vaccination can prevent infections and severe disease, but decisions on how to prioritize risk groups, particularly in limited-resource settings, require a robust evidence base, including global, regional, and local data. What did the researchers do and find? We conducted a systematic review to identify published articles on influenza-associated respiratory disease in hospitalized adults. We then aggregated the data from these articles with data collected by hospital-based influenza surveillance, to calculate a pooled estimate of the proportion of adults hospitalized with respiratory disease who are positive for influenza. Through this approach, we estimated that influenza was associated with 14% of acute respiratory hospitalizations among adults worldwide. This equates to over 5 million influenza-associated hospitalizations per year, with the highest rates among those 65 years and older. What do these findings mean? Estimating the disease burden of influenza allows researchers and policymakers to better understand its global impact across different target groups and allows comparisons with other causes of morbidity and mortality. As global populations age, the importance of vaccinating adults, particularly older adults, is likely to increase.

The photophysical behaviour of a given system can be strongly influenced by the presence of species in high concentrations due to possible excited state interactions, which may lead to the presence of new species in solution - called exciplexes (distinct molecules) or excimers (identical molecules). Since its discovery, species capable of forming exciplexes have been highlighted in important processes such as photodimerization, singlet fission and their use as biosensors. Exciplex formation can be understood based on two types of interaction: excitonic and charge resonances, which suggests a strong multi-referential character for such systems. However, describing the nature of these states is a challenge for medium to large systems due to their high computational cost, requiring the use of single-reference methods such as the time-dependent density functional theory (TD-DFT) and the algebraic diagrammatic construction scheme for the polarization propagator - ADC(2). A related challenge is the basis set choice. This work explores the effect of basis set and level of method on descriptors relevant for exciplex formation such as excitation energy, charge transfer index (CT), exciton average position, natural transition orbitals and the potential energy curves topologies along the ring spacing coordinate. To evaluate the influence of the number of aromatic rings on the exciplex formation, pyrene - naphthalene, pyrene - anthracene, pyrene - pyrene, pyrene - acylpyrene, acylpyrene - acylpyrene were studied. The results suggest that the cc-pVDZ and def2-SV (P) basis set exhibit similar qualitative descriptions in all studied systems. However, significant changes are observed among the tested methods, namely, TD-DFT with several functionals (PBE0, CAM-B3LYP, BHandHLYP and ωB97-XD) and RI-SOS-ADC(2) Regarding structural changes, the increase in the number of aromatic rings led to the increase of stability gain of these systems with the approximation between the fragments, accompanied by the increase of the CT, which is an indication that this parameter is associated with exciplex formation. Meanwhile, the introduction of a carbonyl group led to substantially different descriptions of the RI-SOS-ADC(2) and TD-DFT methods. It was possible to observe a relationship between the presence of possible crossings and differences in the topology of the exciplex potential energy curves with the charge transfer index behaviour along the same coordinates. This relation could be used qualitatively to understand the behaviour of the exciplexes. excited states of these systems. The functional PBE0 consistently disagrees with the description obtained by the other methods in the entire exciplex series studied, suggesting that this is not an appropriate method for these systems. Overall, the BHandHLYP and CAM-B3LYP functionalities show good agreement with each other, as do the TD-DFT / ωB97-XD and RI-SOS-ADC(2) levels. The choice of calculation level has proved to be a crucial step in the study of pyrene exciplexes and should be tested extensively.

Fil: Casal, Mariana Vanina. Univesidad de San Andrés. Escuela de Negocios; Argentina. Barrios, Marcelo

Fil: Casal, Mariana. Universidad de San Andrés. Escuela de Negocios; Argentina. Las personas están cada vez más conscientes de los problemas que ocasiona una mala alimentación, lo que las lleva a una constante búsqueda de opciones saludables. Las diversas necesidades de los consumidores son cubiertas por la gran variedad de productos que ofrece el mercado de bebidas. Dentro de este mercado existe un segmento que sobresale por su nivel nutrimental, y es precisamente AdeS la marca que ha impulsado y desarrollado esta categoría desde su lanzamiento. En este trabajo se desarrolla el plan de negocios del relanzamiento de AdeS, luego de haber sido adquirida por The Coca Cola Company en el año 2016. A través de diferentes herramientas se identificó el segmento objetivo y las necesidades, actualmente no satisfechas de nuestros clientes. La propuesta de valor se basa en brindar una opción saludable en bebidas, la cual aporte nutrición a la alimentación de las personas. e trata de un producto de consumo masivo, que pueda satisfacer las necesidades del rango etario de 20 a 50 años de un nivel socio económico alto/medio-alto. El proyecto requiere una inversión de U$s 229.418, y de acuerdo a los pronósticos y proyecciones económicas, el recupero de la inversión es de un año con una TIR de 116% y un VAN de U$s 2.211.072.

Fil: Ferrer Casal, Mariana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.

Light-to-heat conversion materials generate great interest due to their widespread applications, notable exemplars being solar energy harvesting and photoprotection. Another more recently identified potential application for such material is in molecular heaters for agriculture, whose function is to protect crops from extreme cold weather and extend both the growing season and the geographic areas capable of supporting growth, all of which could help reduce food security challenges. To address this demand, a new series of phenolic-based barbituric absorbers of ultraviolet (UV) radiation has been designed and synthesised in a sustainable manner. The photophysics of these molecules has been studied in solution using femtosecond transient electronic and vibrational absorption spectroscopies, allied with computational simulations and their potential toxicity assessed by in silico studies. Following photoexcitation to the lowest singlet excited state, these barbituric absorbers repopulate the electronic ground state with high fidelity on an ultrafast time scale (within a few picoseconds). The energy relaxation pathway includes a twisted intramolecular charge-transfer state as the system evolves out of the Franck-Condon region, internal conversion to the ground electronic state, and subsequent vibrational cooling. These barbituric absorbers display promising light-to-heat conversion capabilities, are predicted to be non-toxic, and demand further study within neighbouring application-based fields. &nbsp

Light-to-heat conversion materials generate great interest due to their widespread applications, notable exemplars being solar energy harvesting and photoprotection. Another more recently identified potential application for such material is in molecular heaters for agriculture, whose function is to protect crops from extreme cold weather and extend both the growing season and the geographic areas capable of supporting growth, all of which could help reduce food security challenges. To address this demand, a new series of phenolic-based barbituric absorbers of ultraviolet (UV) radiation has been designed and synthesised in a sustainable manner. The photophysics of these molecules has been studied in solution using femtosecond transient electronic and vibrational absorption spectroscopies, allied with computational simulations and their potential toxicity assessed by in silico studies. Following photoexcitation to the lowest singlet excited state, these barbituric absorbers repopulate the electronic ground state with high fidelity on an ultrafast time scale (within a few picoseconds). The energy relaxation pathway includes a twisted intramolecular charge-transfer state as the system evolves out of the Franck-Condon region, internal conversion to the ground electronic state, and subsequent vibrational cooling. These barbituric absorbers display promising light-to-heat conversion capabilities, are predicted to be non-toxic, and demand further study within neighbouring application-based fields.

Fil: Delgado Hernández, Donato. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.