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Synopsis In the interstellar medium polycyclic aromatic hydrocarbon molecules (PAH) are exposed to strong ionizing radation leading to complex organic photochemistry. We investigated these ultrafast fragmentation reactions after ionization of the PAHs phenanthrene, fluorene and pyrene at a wavelength of 30.3 nm using pump probe spectroscopy at a free electron laser. We observe double ionization and afterwards hydrogen abstraction and acetylene loss with characteristic time scales for the reaction processes below one hundred femtoseconds.

The stoichiometry of macromolecular interactions is fundamental to cellular signalling yet challenging to detect from living cells. Fluorescence resonance energy transfer (FRET) is a powerful phenomenon for characterizing close-range interactions whereby a donor fluorophore transfers energy to a closely juxtaposed acceptor. Recognizing that FRET measured from the acceptor’s perspective reports a related but distinct quantity versus the donor, we utilize the ratiometric comparison of the two to obtain the stoichiometry of a complex. Applying this principle to the long-standing controversy of calmodulin binding to ion channels, we find a surprising Ca 2+ -induced switch in calmodulin stoichiometry with Ca 2+ channels—one calmodulin binds at basal cytosolic Ca 2+ levels while two calmodulins interact following Ca 2+ elevation. This feature is curiously absent for the related Na channels, also potently regulated by calmodulin. Overall, our assay adds to a burgeoning toolkit to pursue quantitative biochemistry of dynamic signalling complexes in living cells. Measuring the in vivo stoichiometry of protein-protein interactions is challenging. Here the authors take a FRET-based approach, quantifying stoichiometry based on ratiometric comparison of donor and acceptor fluorescence, and apply their method to report on a Ca2 + -induced switch in calmodulin binding to Ca 2+ ion channels.

One of the methods commonly used to treat biomass waste, including rice husks, is pyrolysis and gasification, both of which produce smoke that can disturb the surrounding environment. This study aims to optimize the conversion process of smoke released in the pyrolysis process of rice husks into two products at once, namely liquid smoke and producer gas. This study designed a Liquid Collection System (LCS) with a shell and tube type knock-down condenser mechanism where the hot smoke is cooled so that the components of the condensed smoke (become liquid smoke) are separated from the non-condensable components (become producer gas). The composition of the LCS coolant, a mixture of Ethylene Glycol and Water, is simulated with the help of Computational Fluid Dynamics (CFD) software to optimize the heat transfer effectiveness value obtained. The simulation results show that the heat transfer efficiency of the volume variation of Ethylene Glycol in the mixture with the volume ratio of Ethylene Glycol and Water is 0:100, 10:90, 20:80, and 30:70 is 9.43%, 13.21%, 15.32%, and 15.43%, respectively. The highest efficiency value was obtained at the highest Ethylene Glycol content, which was a ratio of 30:70.

This study reports the simulation of rice husk pyrolysis units in various sizes of chimneys to investigate the effect of chimney diameter on temperature and heat distribution. The modeling design was carried out using Solidworks 2020 software with 3d modeling, and flow simulation features where the diameters of the chimneys were varied, namely 3, 4, 5, 6, and 8 inches. Simulation of the pyrolysis process with an input temperature of 450 °C and an average fluid velocity of 2.344 m/s for chimney diameters of 3, 4, 5, 6, and 8 inches has resulted in a condenser heat-temperature (TH) of 169.84 °C, 170.04 °C, 171.36 °C, 170.31 °C, and 168.05°C. It produces cold-temperature (TC) of 41.97 °C, 42.88 °C, 42.31 °C, 42.38 °C, and 45.35°C, respectively. The simulation results also show that the larger the chimney size of the pyrolysis tank, the greater the need for heat from the stove fire; conversely, the tank capacity of the husk becomes smaller.

Polycyclic aromatic hydrocarbons (PAHs) play an important role in interstellar chemistry and are subject to high energy photons that can induce excitation, ionization, and fragmentation. Previous studies have demonstrated electronic relaxation of parent PAH monocations over 10–100 femtoseconds as a result of beyond-Born-Oppenheimer coupling between the electronic and nuclear dynamics. Here, we investigate three PAH molecules: fluorene, phenanthrene, and pyrene, using ultrafast XUV and IR laser pulses. Simultaneous measurements of the ion yields, ion momenta, and electron momenta as a function of laser pulse delay allow a detailed insight into the various molecular processes. We report relaxation times for the electronically excited PAH * , PAH +* and PAH 2+* states, and show the time-dependent conversion between fragmentation pathways. Additionally, using recoil-frame covariance analysis between ion images, we demonstrate that the dissociation of the PAH 2+ ions favors reaction pathways involving two-body breakup and/or loss of neutral fragments totaling an even number of carbon atoms. Polycyclic aromatic hydrocarbons play an important role in interstellar chemistry, where interaction with high energy photons can induce ionization and fragmentation reactions. Here the authors, with XUV-IR pump-probe experiments, investigate the ultrafast photoinduced dynamics of fluorene, phenanthrene and pyrene, providing insight into their preferred reaction channels.

Polycyclic aromatic hydrocarbons (PAHs) play an important role in interstellar chemistry and are subject to high energy photons that can induce excitation, ionization, and fragmentation. Previous studies have demonstrated electronic relaxation of parent PAH monocations over 10–100 femtoseconds as a result of beyond-Born-Oppenheimer coupling between the electronic and nuclear dynamics. Here, we investigate three PAH molecules: fluorene, phenanthrene, and pyrene, using ultrafast XUV and IR laser pulses. Simultaneous measurements of the ion yields, ion momenta, and electron momenta as a function of laser pulse delay allow a detailed insight into the various molecular processes. We report relaxation times for the electronically excited PAH*, PAH+*and PAH2+*states, and show the time-dependent conversion between fragmentation pathways. Additionally, using recoil-frame covariance analysis between ion images, we demonstrate that the dissociation of the PAH2+ions favors reaction pathways involving two-body breakup and/or loss of neutral fragments totaling an even number of carbon atoms.

Blood cell count was performed using Sysmex Machine (Model Sysmex XP 100) (an automatic multi parameter blood cell counter) manufactured by Sysmex India Pvt. Ltd. Results: Vestibular stimulation limited stress induced changes in total leukocyte count, neutrophil, lymphocyte, monocyte, eosinophil, and absolute eosinophil count, counts in both male and female intervention groups. [2] Stress is defined as a way in which environmental demands on strain on individual's adaptive capacity, resulting in both psychological demands as well as biological changes that could place at risk for illness.™ It affects different functions of the human body such as body metabolism, digestion, appetite, sleep, sexuality, and fertility.™ Acute and chronic psychological stress harms immune system. [5,6] Studies show that lymphocytosis, mobilization of specific lymphocyte subtypes includes cytotoxic cells such as NK cells and CD8T cells, increased NK cell cytotoxicity, increased salivary and serum immunoglobulin A secretion rate, stimulation of aspects of the complement system, enhanced vaccination response, and faster wound healing, immune cell subtypes such as T regulatory cells, memory T cells, and immune cells specific to certain pathogens, such as cytomegalovirus, are sensitive to acute psychological stress. Limitation of the present study includes, the subjects represented in this study were only students of Kerala. [...]the results cannot be generalized to other levels of education, cities, cultures, and other universities.

Abstract Disclosure: J.E. Mosquera: None. S. Agarwal: None. M. Maxwell: None. T. Bryson: None. S. Mirfakhraee: None. A. Berry: None. M.M. Johny: None. S.C. Oltmann: None. A. Mehta: None. A.P. Dackiw: None. A. Islam: None. F. Nwariaku: None. J. Cadeddu: None. S. Woldu: None. L. Jia: None. O. Hamidi: Advisory Board Member; Self; Corcept Therapeutics. Background: Surgical tumor resection is the only curative treatment for localized pheochromocytoma and functioning paraganglioma (PPGL). Adequate preoperative preparation with alpha-adrenergic blockers is key before surgical resection. However, differences in practice achieving alpha blockade between medical endocrinology and surgical teams have not been explored. We aim to assess the impact of medical Endocrinology vs Surgical team alpha-blockade practices on intraoperative and post-operative outcomes. Methods: We conducted a retrospective, longitudinal follow-up study of adult patients with histopathologically-proven PPGL. Patients with evidence of metastatic disease, missing anesthesia data, open adrenalectomy, or incomplete surgical resection were excluded from the study. All patients underwent successful curative laparoscopic/robotic surgery between 2006 and 2023 at our institution. We extracted demographic, clinical, laboratory, hemodynamic data, and post-operative outcomes. The difference between these parameters were assessed using descriptive and non-parametric statistics. Preliminary Results: The cohort comprised 62 patients. We extracted preliminary data on 30 patients (57% men): 15 patients prepped by the Endocrinology team and 15 by the Surgical team (Endocrine Surgery and Urology). The mean (SD) age at surgery was 54 yrs (+-13) in the Endocrinology group vs 48 yrs (+-12) in the Surgical group. All cases were pheochromocytoma, except for one case of paraganglioma in the Endocrinology group. Non-selective alpha blockers (phenoxybenzamine) were used in 4 (27%) patients in the Endocrinology group vs 8 (53%) in the Surgical group. Selective alpha-blockers (ie, doxazosin) were used in 11 (73%) patients in the Endocrinology group vs 8 (53%) patients in the Surgical group. The median duration of alpha blockade was 17 days in the Endocrinology group and 24 days in the Surgical group. Five patients in each group were admitted to the intensive care unit with a mean stay of 1.4 days in the Endocrinology group and 1.0 days in the Surgical group. Comparing some of the variables of interest with preliminary data obtained, the only parameter with a statistical difference was the intravenous fluids given, median - 1850 ml vs 2800 ml (p<0.05) in Endocrinology vs Surgical groups, respectively. Conclusions: In patients with PPGL treated with curative laparoscopic resection, the preparation with alpha blockade therapy has some differences between Endocrinology and Surgical groups. Specifically, we observed that Surgical group was more likely to use non-selective alpha blockers and implement longer duration of preoperative alpha blockade. Patients prepped by the Surgical team received more intravenous fluids intraoperatively. Further data collection and analyses are underway to determine if these practices are associated with outcomes. Presentation: 6/1/2024