Villarrealsaunders1030

Modeling based on the Kühn-Renger-May approach quantified the strength of excitonic coupling in the squaraine aggregates. The strength of excitonic coupling strongly correlated with squaraine hydrophobic region. Dimer aggregates of dichloroindolenine squaraine were found to exhibit the strongest coupling strength of 132 meV (1065 cm-1). In addition, we identified the sites for dye attachment in the DNA HJ that promote the closest spacing between the dyes in their dimers. The extracted aggregate geometries, and the role of electrostatic and steric effects in squaraine aggregation are also discussed. Taken together, these findings provide a deeper insight into how dye structures influence excitonic coupling in dye aggregates covalently templated via DNA, and guidance in design rules for exciton-based materials and devices.Time-correlated single photon counting has been conducted to gain further insights into the short photoluminescence lifetimes (nanosecond) of lead iodide perovskite (MAPbI3) thin films (∼100 nm). We analyze three different morphologies, compact layer, isolated island, and connected large grain films, from 14 to 300 K using a laser excitation power of 370 nJ/cm2. Lifetime fittings from the Generalized Berberan-Santos decay model range from 0.5 to 6.5 ns, pointing to quasi-direct bandgap emission despite the three different sample strains. The high energy band emission for the isolated-island morphology shows fast recombination rate centers up to 4.8 ns-1, compared to the less than 2 ns-1 for the other two morphologies, similar to that expected in a good quality single crystal of MAPbI3. Low-temperature measurements on samples reflect a huge oscillator strength in this material where the free exciton recombination dominates, explaining the fast lifetimes, the low thermal excitation, and the thermal escape obtained.We have used grazing incidence X-ray absorption fine structure spectroscopy at the cobalt K-edge to characterize monolayer CoO films on Pt(111) under ambient pressure exposure to CO and O2, with the aim of identifying the Co phases present and their transformations under oxidizing and reducing conditions. X-ray absorption near edge structure (XANES) spectra show clear changes in the chemical state of Co, with the 2+ state predominant under CO exposure and the 3+ state predominant under O2-rich conditions. Extended X-ray absorption fine structure spectroscopy (EXAFS) analysis shows that the CoO bilayer characterized in ultrahigh vacuum is not formed under the conditions used in this study. Instead, the spectra acquired at low temperatures suggest formation of cobalt hydroxide and oxyhydroxide. At higher temperatures, the spectra indicate dewetting of the film and suggest formation of bulklike Co3O4 under oxidizing conditions. The experiments demonstrate the power of hard X-ray spectroscopy to probe the structures of well-defined oxide monolayers on metal single crystals under realistic catalytic conditions.Boltzmann-exponential thermodynamic laws govern noisy molecular flux in chemical reactions as well as noisy subthreshold electron current flux in transistors. These common mathematical laws enable one to map and simulate arbitrary stochastic biochemical reaction networks in highly efficient cytomorphic systems built on subthreshold analog circuits. Such simulations can accurately model noisy, nonlinear, asynchronous, stiff, and non-modular feedback dynamics in interconnected networks in the physical circuits, automatically. The scaling in simulation time for stochastic networks with the number of reactions or molecules is constant in cytomorphic systems. In contrast, it grows rapidly in digital systems, which are not parallelizable. Therefore, cytomorphic systems enable large-scale supercomputing systems-biology simulations of arbitrary and highly computationally intensive biochemical reaction networks that can nevertheless be compiled to them via digitally programmable parameters and connectivity. We outline how cytomorphic systems can be utilized for rapid drug-cocktail formulation and discovery in future pandemics like COVID-19; can simulate networks important in cancer; and can help automate the design of synthetic biological circuits, e.g. a synthetic biological operational amplifier for robust and precise drug delivery. Thus, just as neuromorphic systems have enabled multiple applications in A.I., cytomorphic systems will enable multiple applications in biology and medicine.For an engineered thick tissue construct to be alive and sustainable, it should be perfusable with respect to nutrients and oxygen. Embedded printing and then removing sacrificial inks in a cross-linkable yield-stress hydrogel matrix bath can serve as a valuable tool for fabricating perfusable tissue constructs. The objective of this study is to investigate the printability of sacrificial inks and the creation of perfusable channels in a cross-linkable yield-stress hydrogel matrix during embedded printing. Pluronic F-127, methylcellulose, and polyvinyl alcohol are selected as three representative sacrificial inks for their different physical and rheological properties. Their printability and removability performances have been evaluated during embedded printing in a gelatin microgel-based gelatin composite matrix bath, which is a cross-linkable yield-stress bath. The ink printability during embedded printing is different from that during printing in air due to the constraining effect of the matrix bath. Sacrificial inks with a shear-thinning property are capable of printing channels with a broad range of filaments by simply tuning the extrusion pressure. Bi-directional diffusion may happen between the sacrificial ink and matrix bath, which affects the sacrificial ink removal process and final channel diameter. As such, sacrificial inks with a low diffusion coefficient for gelatin precursor are desirable to minimize the diffusion from the gelatin precursor solution to minimize the post-printing channel diameter variation. For feasibility demonstration, a multi-channel perfusable alveolar mimic has been successfully designed, printed, and evaluated. The study results in the knowledge of the channel diameter controllability and sacrificial ink removability during embedded printing.Splenic infarction in COVID-19 patients is a rare entity with few documented cases. We report a case of symptomatic complete splenic infarction and discuss COVID-19 related thrombosis, splenic infarction, diagnostic imaging for splenic infarction, and the management. Thrombotic events related to COVID-19 have been reported in unusual locations, and our case highlights an example of one such location, the splenic artery. Contrast enhanced Computed Tomography (CT) is the standard diagnostic modality and will typically reveal foci of hypo-enhancement, peripheral and wedge-shaped. CT angiography can be performed to evaluate the arteries and diagnose thrombosis. The primary treatment is aimed at addressing the underlying cause and includes supportive care. It is important that physicians consider splenic infarction as an explanation for abdominal pain in COVID-19 patients.Extranodal nasal NK/Tcell lymphoma (ENKTCL) is a relatively rare type of non-Hodgkin's lymphoma. It is highly malignant, highly invasive, and easy to relapse. Most patients have a poor prognosis. We report a 48-year-old woman who presented with irritant dry cough that had persisted for 6 m. CT showed a mass in the right nasal cavity, with uneven density similar to soft tissue, with slight uneven enhancement. The mass and the upper, middle, and lower turbinates were not clearly demarcated, involving multiple adjacent sinus cavities, and the local bone showed osteolytic destruction; MRI showed isosignal on T1WI and slightly hypersignal on T2WI and DWI. In addition, there was a mass of soft tissue density at the bronchial opening in the right middle lobe, showing uneven and obvious enhancement; a cavity was seen in the nodule of the right lower lobe, and the adjacent pleura was stretched, showing moderate enhancement. The nasal mass was diagnosed as extranodal NK/T cell lymphoma, the right middle lobe mass was diagnosed as mucoepidermoid carcinoma, and the right lower lobe mass was diagnosed as lung adenocarcinoma. ENKTCL rarely invades the lungs. If a patient has a lung occupying lesion similar to it, biopsy confirmation should be considered to avoid misdiagnosis as a chest metastasis that affects the treatment effect.Sequestration is a congenital abnormality that can occur in both children and adults. The clinical presentation often manifests as recurrent pneumonia throughout the lifetime of the patient. Pathologically, sequestration is a disorganized region of lung parenchyma without a normal pulmonary artery and with no interconnecting air passage (ie, it is isolated from the bronchi and pulmonary arteries). Sequestration can be either intralobar or extralobar and is usually supplied with blood from an anomalous vessel originating from the thoracic aorta or abdominal aorta (big circulation/systemic circulation), which is one of the mandatory criteria for diagnosing sequestration. CT angiography or catheter angiography can assist in identifying the anomalous vessel both for diagnosis and surgical resection. We present a rare case of intralobar sequestration with the distinction of being supplied with blood from the abdominal vena cava, as confirmed by CT angiography, surgery, and postoperative pathology. It is hoped that this study will contribute to the literature by introducing a rare case of congenital lung abnormality and pulmonary vascular malformation.A 77-year-old Caucasian man, a former surveyor in a chemical company, underwent a chest X-ray (CXR) as a follow-up exam for a melanoma of the back, surgically removed. CXR showed interstitial thickening in both lower lobes; then, a high-resolution computed tomography of the chest (HRCT) was performed to further investigate these findings, revealing multiple small, calcified nodules with branching appearance at both lung bases. Clinical examination and exposure history were negative, except for a decrease in diffusing capacity for carbon monoxide resulting from pulmonary function tests. Surgical lung biopsy was performed; histology revealed numerous nodules and branching tubules of bone tissue, some of which with marrow elements. After multidisciplinary discussion of the case, a diagnosis of idiopathic diffuse pulmonary ossification (DPO) was considered. see more Clinical status of the patient was stable over time, despite the increase in extent of calcifications. DPO is an uncommon condition that should be considered in different clinical-radiological settings; multidisciplinary discussion is essential for the final diagnosis.Appendiceal mucocele (AM) is a rare lesion found in only 0.3% of all appendectomies and it is characterized by distention of the appendix by the accumulating intraluminal mucinous material. Four main histopathological subtypes of appendiceal mucocele has been described including retention cyst, mucosal hyperplasia, mucinous cystadenoma, and cystadenocarcinoma. We report a case of 48-year-old middle eastern female, previously healthy, presented to the primary health center with right iliac fossa discomfort, and referred to our hospital for further evaluation. Contrast enhanced computed tomography of the abdomen and pelvis and focused ultrasonography over the right iliac fossa showed the characteristic CT and sonographic appearance of appendiceal mucocele. An additional incidental note of lack of colonic haustral pattern involving the rectum and descending colon was noted on abdominal CT raising the suspicion of Ulcerative Colitis which was then confirmed by colonoscopy and histopathology. Although no causal relationship between appendicular mucocele and inflammatory bowel disease has been established yet and few case reports had reported appendicular mucocele in patients with ulcerative colitis, close surveillance in these patients, and early recognition of the characteristic imaging features is crucial in preventing dreadful complications like pseudomyxoma peritonei.