Are there really cooper pairs and persistent currents in aromatic molecules?

arXiv.orgOver 20 years ago, one of us suggested the title was affirmative. In 2012, Cooper pairs were identified in several, but not all >aromatic> compounds tested, benzene being one. This manuscript discusses the formation of three time-reversed pairs of states forming pseudobosons (high energy Cooper pairs) in benzene at room temperature. The large stabilization in energy that results is the additive effect of energy gaps of an s wave state and a charge density wave permitting the pseudobosons to exist at room temperature. The overall result of these interactions is three pseudobosons occupying the lowest boson state and the positions of the carbon nuclei are optimum by forming a perfect hexagon. The possibility of a persistent current exists; detection might not be easy.Peer Reviewe

Instantaneous band gap collapse in photoexcited monoclinic VO2_2 due to photocarrier doping

Using femtosecond time-resolved photoelectron spectroscopy we demonstrate that photoexcitation transforms monoclinic VO$_2$ quasi-instantaneously into a metal. Thereby, we exclude an 80 femtosecond structural bottleneck for the photoinduced electronic phase transition of VO$_2$. First-principles many-body perturbation theory calculations reveal a high sensitivity of the VO$_2$ bandgap to variations of the dynamically screened Coulomb interaction, supporting a fully electronically driven isostructral insulator-to-metal transition. We thus conclude that the ultrafast band structure renormalization is caused by photoexcitation of carriers from localized V 3d valence states, strongly changing the screening \emph{before} significant hot-carrier relaxation or ionic motion has occurred

Centro artesanal de conservación y rentabilidad para la producción medicinal y nutricional de la algarroba en el Bosque de Pomac, Ferreñafe 2022

La presente investigación fue realizada en, CC.PP. MM. Cachinche ubicado en la provincia de Ferreñafe, Lambayeque. Donde se determinó como principal problema la reducción artificial y natural del área de uso del bosque de Pomac, limitado uso medicinal y nutricional de la algarroba. el objetivo principal de esta investigación es generar una propuesta de diseño de un “Centro artesanal de conservación para la producción medicinal y nutricional de la algarroba en el bosque de Pomac, Ferreñafe”. La realización de este proyecto que es de carácter cuantitativo, critica y proyectiva. Tiene como instrumento las entrevistas al presidente de la comunidad el cual dada su edad y conocimiento sobre la población y sus recursos nos pudo dar una respuesta más certera y cercana a la realidad. Para la cual se diagnosticó una reducción artificial y natural del área de uso del bosque de algarrobo, limitado uso medicinal y nutricional de la algarroba, producción del carbón a partir del árbol del algarrobo, así mismo que los CC.PP.MM, Cachinche y la Zaranda son los únicos productores mayor ligados al producto de la algarroba en la región. De manera similar, se creó un centro de arte considerando los tipos de escenarios e infraestructura requeridos y suficientes para el valioso avance de las actividades; de acuerdo a las disposiciones y requerimientos. obteniendo una deducción que nos apunta en la dirección del proyecto arquitectónico, que se adhiere a los estándares establecidos por el Perú.TesisInfraestructura, Tecnología y Medio Ambient

Excitation by Axon Terminal GABA Spillover in a Sound Localization Circuit

Synapses from neurons of the medial nucleus of the trapezoid body (MNTB) onto neurons of the lateral superior olive (LSO) in the auditory brainstem are glycinergic in maturity, but also GABAergic and glutamatergic in development. The role for this neurotransmitter cotransmission is poorly understood. Here we use electrophysiological recordings in brainstem slices from P3-P21 mice to demonstrate that GABA release evoked from MNTB axons can spill over to neighboring MNTB axons and cause excitation by activating GABAAR. This spillover excitation generates patterns of staggered neurotransmitter release from different MNTB axons resulting in characteristic “doublet” postsynaptic currents in LSO neurons. Postembedding immunogold labeling and electron microscopy provide evidence that GABAARs are localized at MNTB axon terminals. Photolytic uncaging of p-hydroxyphenacyl (pHP) GABA demonstrates backpropagation of GABAAR-mediated depolarizations from MNTB axon terminals to the soma, some hundreds of microns away. These somatic depolarizations enhanced somatic excitability by increasing the probability of action potential generation. GABA spillover excitation between MNTB axon terminals may entrain neighboring MNTB neurons, which may play a role in the developmental refinement of the MNTB-LSO pathway. Axonal spillover excitation persisted beyond the second postnatal week, suggesting that this mechanism may play a role in sound localization, by providing new avenues of communication between MNTB neurons via their distal axonal projections. SIGNIFICANCE STATEMENT In this study, a new mechanism of neuronal communication between auditory synapses in the mammalian sound localization pathway is described. Evidence is provided that the inhibitory neurotransmitter GABA can spill over between axon terminals to cause excitation of nearby synapses to further stimulate neurotransmitter release. Excitatory GABA spillover between inhibitory axon terminals may have important implications for the development and refinement of this auditory circuit and may play a role in the ability to precisely localize sound sources

Comparación de las escalas APACHE II y BISAP en el pronóstico de pancreatitis aguda en un hospital del Perú: Comparison of the APACHE II and BISAP scales in the prognosis of acute pancreatitis in a hospital of Peru

Introduction:  Acute pancreatitis continue to be a disease with significant morbidity and mortality. It is diagnosed by clinical criteria and the inflammatory process can lead to organ failure. The objective of the present study was to compare the scales of APACHE II and BISAP in the development of organic failure in acute pancreatitis from a public hospital of Perú. Pacients and methods: An analytical from validation of a diagnostic test. There were clinical records of patients who were hospitalized with the diagnosis of acute pancreatitis in the Internal Medicine service and the Intensive Care Unit were evaluated. The APACHE II and BISAP scales were applied and the ROC curve, the sensitivity, the specificity, the positive and negative predictive value was calculated for each one. SPSSv23 was used for statistical analysis. Results: Were reviewed 146 stories that met the inclusion criteria. An area under the curve of 0.957 was obtained for BISAP and 0.996 for APACHE II; with a sensitivity and specificity for APACHE II of 83% and  99%,  for BISAP of 66% and 99%. In addition, the positive and negative predictive value for APACHE II is 83% and 99% ,  for BISAP 80% and 98% . Conclusion: The APACHE II scale was superior for detecting organ failure. It was determined that both scales have high specificity, however the APACHE II scale presented a higher sensitivity than the BISAP scale.Introducción: La pancreatitis aguda continúa siendo una enfermedad con morbilidad y mortalidad significativas. Se diagnostica mediante criterios clínicos y el proceso inflamatorio puede llegar hasta una falla de órganos. El objetivo del presente estudio fue comparar las escalas de APACHE II y BISAP en el desarrollo de falla orgánica en pacientes con pancreatitis aguda de un hospital público del Perú. Pacientes y métodos: Se realizó un estudio de validación de prueba diagnóstica. Se evaluaron las historias clínicas de pacientes que estuvieron hospitalizados con el diagnostico de pancreatitis aguda en el servicio de Medicina Interna y la Unidad de Cuidados Intensivos. Se aplicó las escalas APACHE II y BISAP, se calculó la curva ROC, sensibilidad, especificidad, valor predictivo positivo y negativo. Para el análisis estadístico se utilizó el SPSSv23. Resultados: Se evaluaron 146 historias de pacientes que cumplían con los criterios de inclusión. Se obtuvo un área bajo la curva de 0.957 para BISAP y 0.996 para APACHE II; con una sensibilidad y especificidad para APACHE II de 83% y 99%,  para BISAP de 66% y 99%. El valor predictivo positivo y negativo para APACHE II es 83% and 99% y para BISAP 80% y 98%. Conclusiones: La escala de APACHE II fue superior para detectar falla de órganos. Se determinó que ambas escalas poseen alta especificidad, siendo mayor la sensibilidad en la escala BISAP

Evaluación farmacoeconómica con modelización comparando dos esquemas terapéuticos con carbetocina y oxitocina para la prevención de la hemorragia postparto por cesárea (Lima, Perú).

Postpartum hemorrhage is one of the main causes of maternal death. Oxytocin has traditionally been used to prevent postpartum hemorrhage. Aim: To compare oxytocin with carbetocin, a long-acting analog of oxytocin, for prevention of uterine hemorrhage after cesarean delivery. Materials & methods: Clinical data were retrieved from the 2012 Cochrane meta-analysis “Carbetocin for preventing postpartum hemorrhage”. A decision tree was constructed. The direct costs were those of medications from the Peruvian official price list (DIGEMID). Costs associated with additional oxytocic drugs, blood transfusions, postpartum hemorrhage kits and hysterectomy were obtained from Hospital Nacional Edgardo Rebagliati Martins. The perspective of the study was that of the payer. The time horizon for calculating quality-adjusted life years (QALYs) was 1 year (2015). Results: Patients who received carbetocin required fewer additional uterotonic agents, had fewer hemorrhages and received fewer blood transfusions. Therefore, the costs associated with these interventions were lower. The incremental cost–effectiveness ratio was S/. 49,918 per QALY gained, which is lower than the threshold we estimated for Peru. Conclusion: Carbetocin is more cost-effective than oxytocin for prevention of uterine hemorrhage after cesarean delivery.La hemorragia postparto es una de las principales causas de mortalidad materna tanto en los países en desarrollo como en los desarrollados. Según la OMS, Cada día mueren en todo el mundo unas 800 mujeres por complicaciones relacionadas con el embarazo o el parto. Así mismo , se estima que la hemorragia postparto severa se presenta en alrededor del 11% de las mujeres que tiene parto de un nacido vivo (1). En el Perú, en el año 2015 se produjeron 414 muertes maternas y aproximadamente el 42 % es debido a hemorragia (16). Durante el año 2014, en el Seguro Social de salud del Perú (ESSALUD) se reportaron 49 muertes maternas, representando un 11% de las muertes maternas del país. La hemorragia uterina es la tercera causa de muerte materna en ESSALUD, puede presentarse hasta en un 10% del total de partos, 4% corresponden a partos vaginales y 6% a cesáreas (17).pre-print543 K

Fresnel-Floquet theory of light-induced terahertz reflectivity amplification in Ta2NiSe5

We theoretically investigate a new pathway for terahertz parametric amplification, initiated by above-gap optical excitation in the candidate excitonic insulator Ta2NiSe5. We show that after electron photoexcitation, electron-phonon coupling can lead to THz parametric amplification, mediated by squeezed oscillations of the strongly coupled phonon. The developed theory is supported by experimental results on Ta2NiSe5 where photoexcitation with short pulses leads to enhanced terahertz reflectivity. We explain the key mechanism leading to parametric amplification in terms of a simplified Hamiltonian and demonstrate the validity of the simplified model in Ta2NiSe5 using DFT ab-initio calculations. We identify a unique 4.7 THz infrared active phonon that is preferentially coupled to the electronic bandstructure, providing a dominant contribution to the low frequency terahertz amplification. Moreover, we show that the electron-phonon coupling is strongly dependent on the order parameter. Our theory suggests that the pumped Ta2NiSe5 is a gain medium which can be used to create THz amplifiers in THz communication applications.Comment: Main: 24 pages, 2 figures. Supplementary: 8 pages, 3 figures, 2 table

Substituted tetrahydroisoquinolines: synthesis, characterization, antitumor activity and other biological properties

A novel group of aryl methyl sulfones based on nonsteroidal anti-inflammatory compounds exhibiting a methyl sulfone instead of the acetic or propionic acid group was designed, synthesized and evaluated in vitro for inhibition against the human cyclooxygenase of COX-1 and COX-2 isoenzymes and in vivo for anti-inflammatory activity using the carrageenan induced rat paw edema model in rats. Also, in vitro chemosensitivity and in vivo analgesic and intestinal side effects were determined for defining the therapeutic and safety profile. Molecular modeling assisted the design of compounds and the interpretation of the experimental results. Biological assay results showed that methyl sulfone compounds 2 and 7 were the most potent COX inhibitors (IC50 between 0.04 and 0.71 M). Also, these highly active methyl sulfones displayed greater COX-2 activity than the parent carboxylic NSAIDs, thus indicating that the replacement of the acetic or propionic acids by a methyl sulfone group enables some of these structures to possess higher COX-2 inhibitory activity than that of the corresponding alkyl carboxylic analogues. The improved inhibitory activity is attributed to the higher flexibility of the sulfone-receptor interaction that enables more profound exploration of the binding site compared with that of acidic analogues. This observation is underpinned by molecular modeling studies that indicates a change in the binding mode or mechanism compared to the standard binding mode displayed by ibuprofen. The most promising compounds 2 and 7 possess a therapeutical profile that enables their chemical scaffolds to be utilized for development of new NSAIDs