Oxidation of iron by giant impact and its implication on the formation of reduced atmosphere in the early Earth

Giant impact-driven redox processes in the atmosphere and magma ocean played crucial roles in the evolution of Earth. However, because of the absence of rock records from that time, understanding these processes has proven challenging. Here, we present experimental results that simulate the giant impact-driven reactions between iron and volatiles (H2O and CO2) using x-ray free electron laser (XFEL) as fast heat pump and structural probe. Under XFEL pump, iron is oxidized to wüstite (FeO), while volatiles are reduced to H2 and CO. Furthermore, iron oxidation proceeds into formation of hydrides (γ-FeHx) and siderite (FeCO3), implying redox boundary near 300-km depth. Through quantitative analysis on reaction products, we estimate the volatile and FeO budgets in bulk silicate Earth, supporting the Theia hypothesis. Our findings shed light on the fast and short-lived process that led to reduced atmosphere, required for the emergence of prebiotic organic molecules in the early Earth.

Changes in Dental Biofilm Proteins' Secondary Structure in Groups of People with Different Cariogenic Situations in the Oral Cavity and Using Medications by Means of Synchrotron FTIR-Microspectroscopy

This work unveils the idea that the cariogenic status of the oral cavity (the presence of active caries lesions) can be predicted via a lineshape analysis of the infrared spectral signatures of the secondary structure of proteins in dental biofilms. These spectral signatures that work as natural markers also show strong sensitivity to the application in patients of a so-called modulator-a medicinal agent (a pelleted mineral complex with calcium glycerophosphate). For the first time, according to our knowledge, in terms of deconvolution of the complete spectral profile of the amide I and amide II bands, significant intra- and intergroup differences were determined in the secondary structure of proteins in the dental biofilm of patients with a healthy oral cavity and with a carious pathology. This allowed to conduct a mathematical assessment of the spectral shifts in proteins' secondary structure in connection with the cariogenic situation in the oral cavity and with an external modulation. It was shown that only for the component parallel β-strands in the amide profile of the biofilm, a statistically significant (p < 0.05) change in its percentage weight (composition) was registered in a cariogenic situation (presence of active caries lesions). Note that no significant differences were detected in a normal situation (control) and in the presence of a carious pathology before and after the application of the modulator. The change in the frequency and percentage weight of parallel β-strands in the spectra of dental biofilms proved to be the result of the presence of cariogenic mutans streptococci in the film as well as of the products of their metabolism-glucan polymers. We foresee that the results presented here can inherently provide the basis for the infrared spectral diagnosis of changes (shifts) in the oral microbiome driven by the development of the carious process in the oral cavity as well as for the choice of optimal therapeutic treatments of caries based on microbiome-directed prevention measures.

Surface figure correction with roughness reduction using carbon-doped platinum film for high-precision X-ray mirror fabrication

To obtain the surface shape of an X-ray mirror with high precision, a differential deposition method was used instead of a direct removal method. To modify the mirror surface shape using the differential deposition method, it is necessary to coat it with a thick film, and the co-deposition method is used to suppress the increase in surface roughness. The addition of C to the Pt thin film, which is often used as an X-ray optical thin film, resulted in lower surface roughness compared with that with the Pt coating alone, and the stress change according to the thin film thickness was evaluated. Differential deposition controls the speed of the substrate during coating based on continuous motion. The stage was controlled by calculating the dwell time through deconvolution calculations based on the accurate measurement of the unit coating distribution and target shape. We successfully fabricated an X-ray mirror with high precision. This study indicated that an X-ray mirror surface could be manufactured by modifying the surface shape at a micrometer level through the coating. Changing the shape of existing mirrors can not only result in the manufacture of high-precision X-ray mirrors but also improve their performance.

Near-field infrared nanoscopic study of EUV- and e-beam-exposed hydrogen silsesquioxane photoresist

This article presents a technique of scattering-type scanning near-field optical microscopy (s-SNOM) based on scanning probe microscopy as a nanoscale-resolution chemical visualization technique of the structural changes in photoresist thin films. Chemical investigations were conducted in the nanometer regime by highly concentrated near-field infrared on the sharp apex of the metal-coated atomic force microscopy (AFM) tip. When s-SNOM was applied along with Fourier transform infrared spectroscopy to characterize the extreme UV- and electron-beam (e-beam)-exposed hydrogen silsesquioxane films, line and space patterns of half-pitch 100, 200, 300, and 500 nm could be successfully visualized prior to pattern development in the chemical solutions. The linewidth and line edge roughness values of the exposed domains obtained by s-SNOM were comparable to those extracted from the AFM and scanning electron microscopy images after development. The chemical analysis capabilities provided by s-SNOM provide new analytical opportunities that are not possible with traditional e-beam-based photoresist measurement, thus allowing information to be obtained without interference from non-photoreaction processes such as wet development.

In-depth probing of thermally-driven phase separation behavior of lamella-forming PS-b-PMMA films by infrared nanoscopy

A non-invasive, image-based analytic method utilizing scattering-type scanning near-field optical microscopy (s-SNOM) is suggested to evaluate the phase separation behavior of lamella-forming polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) block copolymer films. Taking advantage of the penetrability of the tip-enhanced IR signal into the films, the spatio-spectral maps of each component are constructed. Subsequently, the effect of a sole and combinatorial applications of the self-assembly procedures, such as solvent vapor annealing (SVA) and/or thermal annealing (TA), on the spatial distribution of PS or PMMA components is quantitatively assessed in terms of the areal portions of the PS domain, PMMA domain, and the mixed zone that is adjacent to the domain border. Additionally, by statistically comparing the local concentration profiles, the chemical contrast between the domains turns out to be dependent upon the annealing procedures (namely, SVA and SVA + TA). This technique can pave the way to an uncomplicated but precise investigation of the polymer nanostructure-based thin film devices whose performances are critically governed by the spatial arrangement of the chemical elements.

Selective CO2 adsorption and bathochromic shift in a phosphocholine-based lipid and conjugated polymer assembly

We assemble a film of a phosphocholine-based lipid and a crystalline conjugated polymer using hydrophobic interactions between the alkyl tails of the lipid and alkyl side chains of the polymer, and demonstrated its selective gas adsorption properties and the polymer's improved light absorption properties. We show that a strong attractive interaction between the polar lipid heads and CO₂ was responsible for 6 times more CO₂ being adsorbed onto the assembly than N₂, and that with repeated CO₂ adsorption and vacuuming procedures, the assembly structures of the lipid-polymer assembly were irreversibly changed, as demonstrated by in situ grazing-incidence X-ray diffraction during the gas adsorption and desorption. Despite the disruption of the lipid structure caused by adsorbed polar gas molecules on polar head groups, gas adsorption could promote orderly alkyl chain packing by inducing compressive strain, resulting in enhanced electron delocalization of conjugated backbones and bathochromic light absorption. The findings suggest that merging the structures of the crystalline functional polymer and lipid bilayer is a viable option for solar energy-converting systems that use conjugated polymers as a light harvester and the polar heads as CO₂-capturing sites.

Assembly films of a phosphocholine-based lipid and a crystalline conjugated polymer had significant CO₂ selective adsorption and light absorption due to the attractive interaction of CO₂ with exposed polar lipid heads and enhanced morphologies.

Filiform polyposis in a 20-year-old patient with ulcerative colitis – a rare occurrence

Introduction/Objective

Filiform polyposis (FP), also referred as inflammatory polyposis or pseudopolyposis, is an uncommon benign entity usually diagnosed in patients with history of Crohn’s disease, ulcerative colitis, interstitial tuberculosis or histiocytosis X. It is characterized by multiple finger-like mucosal projections/pseudopolyps seen more commonly in transverse and descending colon. Pathogenesis of FP is uncertain but it is hypothesized to be reactive process to chronic inflammation leading to formation of fingerlike projections. The term filiform polyposis was coined in 1974 by Appleman HD and his collegues to describe numerous long slender worm-like (filiform) colonic lesions seen in radiographs. Herein, we are going to present a case of FP diagnosed in a 20-year-old male with history of medically refractive ulcerative colitis.

Methods/Case Report

The patient is a 20-year-old male, with a history of medically refractive ulcerative colitis on systemic steroids and vedolizumab. He underwent sigmoidoscopy and colonoscopy which reveals multiple pedunculated, polypoid lesions, ranging from 0.5 to 3 cm in length with white tips (cap of purulent mucous). Patient underwent total abdominal colectomy with end ileostomy. The specimen received by our deparment consist of a segment of right colon (63 cm in length, 3.5 cm in diameter) with attached ileum (3 cm in length, 2 cm in diameter) and appendix (6 cm in length, 0.8 cm in diameter). The part of the right colon is constricted/strictured measuring 24 cm in length, 2 cm in diameter. Opening reveals numerous (&gt;100) pedunculated, finger-like polypoid lesions measuring from 0.3 cm to 2 cm in length. The lesions involve the entire right colon including distal colonic surgical margin. Appendix and ileum are not involved by the lesion and grossly unremarkable. Microscopic evaluation of the lesions reveal acute and chronic inflammatory cells, granulation tissue, areas of necrosis and reactive changes with focal mucosal atrophy consistent with chronic ulcerative colitis.

Results (if a Case Study enter NA)

NA

Conclusion

Filiform polyposis (FP) is an uncommon benign entity commonly seen in association with Inflammatory Bowel Diseases. Diagnosing FP requires comprehensive gross and microscopic examination as well as review of clinical history and imaginig studies. Because of its uncommon nature, we recommend to report this entity to raise awareness and to educate the pathologists who have not diagnosed it before.

Identification of Wasted Blood Products at Staten Island University Hospital in 2020 and Institutional Efforts to Reduce Wastage

Introduction/Objective

Blood products are precious resources obtained from donors who donate with the intention to help people. These blood products however do not always go to the patients, instead sometimes ending up in the waste. It is inevitable to have some degree of the wastage due to limited blood product shelf life, the inherent need to have stock on hand at all times, and the often unpredictable demand of these products. However, it is possible to minimize the wastage of blood products with careful management of inventories, proper documentation, and education1. In this study, we aim to identify the amount and cost of wasted blood products at Staten Island University Hospital in 2020, the reasons behind the wastage, and solutions to reduce the wastage.

Methods/Case Report

A retrospective statistical analysis of blood product waste data in 2020 was performed manually with Microsoft Excel. Wastage rate and average cost was calculated, the reasons behind the wastage were identified, and low cost interventions to reduce wastage were planned.

Results (if a Case Study enter NA)

Total number of the wasted blood product is 425 which represents 3.8% of the total inventory at a total cost of $ 97,309.46 which does not include the hours spend by the lab personnel for the wasted products. The most wasted blood component is fresh frozen plasma (FFP) (Table 1). Thawing the frozen blood products (FFP and cryoprecipitate) significantly shortens the shelf life and triggers a lot of wastage through expiration (Table 2). 32.5 % of the wasted products are wasted due to expiration on the shelf (Diagram 1). Other reasons for the wastage includes patient unreadiness, patient refusal, late return of unused products etc. (Graph 1).

Conclusion

Educating clinical and laboratory team members about the reasons for wasted blood products and strategies to reduce it might significantly reduce the wastage. Appropriate activation and immediate deactivation of massive transfusion protocol (MTP) would be one of the most important aspect of this education. Expired thawed blood product is the largest contributor to wastage, and MTP is the main reason for thawing. Preventing unnecessary MTP activation minimizes over-thawing and therefore minimizes the expiration and wastage. Documentation of the wasted blood product should be improved to better identify the reasons behind wastage.

Programmable Synthesis of Silver Wheels

The synthesis of sandwich-shaped multinuclear silver complexes with planar penta- and tetranuclear wheel-shaped silver units and a central anion, [Ag_n(2-HPB)₂(A^-)](OTf^-)_n-1, nAg^A, n = 4 or 5 and A^- = OH^- or F^- or Cl^-, is reported, along with complete spectroscopic and structural characterization. An NMR mechanistic study reveals that silver complexes were formed in the following order: 2Ag → 3Ag^H₂O → 5Ag^OH → 4Ag^OH. The central hydroxides in 4Ag^OH and 5Ag^OH exhibit exotic physical properties due to the confined environment inside the complex. The size of these silver wheels can be tuned by changing the central anion or extracting/adding one silver atom. This study provides the facile way to synthesize discrete wheel-shaped multinuclear silver complexes and provides valuable insights into the dynamics of the self-assembly process.

Studies on Chemical IR Images of Poly(hydroxybutyrate⁻co⁻hydroxyhexanoate)/Poly(ethylene glycol) Blends and Two-Dimensional Correlation Spectroscopy

Biodegradable poly-[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoates] (PHBHx) have been widely studied for their applications in potentially replacing petroleum-based thermoplastics. In this study, the effect of the high molecular weight (Mn = 3400) poly(ethylene glycol) (PEG) blended in the films of PHBHx with different ratios of PEG was investigated using chemical FTIR imaging. Chemical IR images and FTIR spectra measured with increasing temperature revealed that PEG plays an important role in changing the kinetics of PHBHx crystallization. In addition, two-dimensional correlation spectra clearly showed that thermal properties of PHBHx/PEG blend film changed when the blending ratio of PHBHx/PEG were 60/40 and 50/50. Consequently, PEG leads to changes in the thermal behavior of PHBHx copolymers.

Preparation and Characterization of Transparent Polyimide⁻Silica Composite Films Using Polyimide with Carboxylic Acid Groups

Polyimide (PI) composite films with thicknesses of approximately 100 µm were prepared via a sol–gel reaction of 3-aminopropyltrimethoxysilane (APTMS) with poly(amic acid) (PAA) composite solutions using a thermal imidization process. PAA was synthesized by a conventional condensation reaction of two diamines, 3,5-diaminobenzoic acid (DABA), which has a carboxylic acid side group, and 2,2′-bis(trifluoromethyl)benzidine (TFMB), with 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) in N,N-dimethylacetamide (DMAc). The PAA–silica composite solutions were prepared by mixing PAA with carboxylic acid side groups and various amounts of APTMS in a sol–gel process in DMAc using hydrochloric acid as a catalyst. The obtained PI–silica composite films showed relatively good thermal stability, and the thermal stability increased with increasing APTMS content. The optical properties and in-plane coefficient of thermal expansion (CTE) values of the PI–silica composite films were investigated. The CTE of the PI–silica composite films changed from 52.0 to 42.1 ppm/°C as the initial content of APTMS varied. The haze values and yellowness indices of the composite films increased as a function of the APTMS content.

Investigation of phase separated polyimide blend films containing boron nitride using FTIR imaging

Immiscible aromatic polyimide (PI) blend films and a PI blend film incorporated with thermally conductive boron nitride (BN) were prepared, and their phase separation behaviors were examined by optical microscopy and FTIR imaging. The 2,2'-bis(trifluoromethyl)benzidine (TFMB)-containing and 4,4'-thiodianiline (TDA)-containing aromatic PI blend films and a PI blend/BN composite film show two clearly separated regions; one region is the TFMB-rich phase, and the other region is the TDA-rich phase. The introduction of BN induces morphological changes in the immiscible aromatic PI blend film without altering the composition of either domain. In particular, the BN is selectively incorporated into the TDA-rich phase in this study.

Rubbed Thin Films of Well-defined Brush Polyimides for Flat-Panel Liquid Crystal Displays: Surface Morphology, Molecular Orientation, and Liquid Crystal Alignability

A series of well-defined brush polyimide (PI) composed of two 4- n-alkyloxyphenyloxy bristles per repeat unit on a semi-rigid poly(4,4′-methylenyldiphenylene pyromellitimide), Cm-PMDA-MDA PIs, were synthesized and their nanoscale thin films prepared by conventional spin-coating of their soluble poly(amic acid) precursor solutions and subsequent drying and thermal imidization in a nitrogen atmosphere. All the PIs were determined to be a positively birefringent polymer. The surface morphology and molecular orientation of each PI in films before and after rubbing were investigated in detail by atomic force microscopy, optical retardation analysis, and linearly polarized infrared spectroscopy. The sequence of the rubbing-induced polymer segmental orientations was further investigated in detail. In addition, the liquid crystal alignment and pretilt ability of the rubbed PI films were examined, and their thermal stability investigated. The present study provides important information on the sequence of the polymer segmental orientations induced by rubbing and additionally the mechanisms of the alignment and pretilt of liquid crystal molecules in contact with the rubbed PI film surface.

Two-dimensional correlation analysis study of the photo-induced molecular reorientations of photosensitive polyester film containing 1,4-phenylenediacryloyl units in the backbone

The photochemical reaction and molecular reorientation of a novel photosensitive polyester, poly[oxy(4-n-butyl-3,5-benzoate)oxy-1,4-phenylenediacryloyl] (PPDA-C4BZ), which contains n-butyl side groups and 1,4-phenylenediacryloyl units (PDA chromophores) in the main chain, are reported in detail. We applied two-dimensional (2D) correlation analysis for the infrared (IR) and ultraviolet (UV) absorption spectra of nanoscaled films of PPDA-C4BZ to establish the sequence of the photo-induced segmental reorientations that result from UV irradiation. The photochemical reaction was found to have a greater effect on the polymer's main chains than on its side groups and to induce the reorientation of the polymer molecules. In particular, a cycloaddition process occurs first in the PDA chromophore units and then the local reorientation of the polymer molecules is induced. Namely, such photodimerization of the PDA chromophores induces the molecular reorientations of the PDA chromophores and the benzoate units in the main chain. The photo-induced molecular reorientations occur in the following sequence: photodimerization --> benzoate units --> PDA chromophores --> n-butyl side groups. In addition, a two-dimensional map of the first derivatives of the UV absorption spectra with respect to the exposure energy provided evidence of the formation of head-to-head aggregates (i.e., H-aggregates) of PPDA-C4BZ molecules.