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Abstract The photorefractive properties of triphenylamine polymer-based composites with various composition ratios were investigated via optical diffraction, response time, asymmetric energy transfer, and transient photocurrent. The composite consisted of a photoconductive polymer of poly((4-diphenylamino)benzyl acrylate), a photoconductive plasticizer of (4-diphenylamino)phenyl)methanol, a sensitizer of [6,6]-phenyl-C61-butyric acid methyl ester, and a nonlinear optical dye of (4-(azepan-1-yl)-benzylidene)malononitrile. The photorefractive properties and related quantities were dependent on the composition, which was related to the glass transition temperature of the photorefractive polymers. The quantum efficiency (QE) of photocarrier generation was evaluated from the initial slope of the transient photocurrent. Transient photocurrents were measured and showed two unique peaks: one in the range of 10−4 to 10−3 s and the other in the range of 10−1 to 1 s. The transient photocurrents was well simulated (or reproduced) by the expanded two-trapping site model with two kinds of photocarrier generation and recombination processes and two different trapping sites. The obtained photorefractive quantity of trap density was significantly related to the photoconductive parameters of QE.

This paper investigates the possibilities of complex nonlinear dynamic signal generation using a simple photorefractive two-wave mixing system without any feedback using numerical simulations. The novel idea is to apply a sinusoidal electric field to the system inroder to extract nonlinear dynamic behavior. The mathematical model of the system was constructed using Kogelnick’s coupled wave equations and Kukhtarev’s material equation. The spatio-temporal evolution of the system was simulated in discrete steps numerically. The temporal evolution of the output light intensity exhibits period doubling, behavior which is a characteristic feature of complex nonlinear dynamic systems. A bifurcation diagram and Lyapunov exponentials confirm the presence of the period-doubling route to chaos in the system. The observed complex signal pattern varies uniformly with respect to the amplitude of the applied field, indicating a controllable nonlinear dynamic behavior. Such a system can be very useful in applications such as photonic reservoir computing, in-materio computing, photonic neuromorphic networks, complex signal detection, and time series prediction.

Abstract Background Tracheal perforation, although rare, is a known late complication of tracheostomy tube placement. Case presentation We present a 7-year-old boy with severe physical and mental disabilities under tracheostomy and long-term mechanical ventilation and steroid therapy who suddenly developed obstructive shock secondary to pneumomediastinum and pneumothorax. Prior bronchoscopy had shown the tip of the tracheostomy tube contacting the posterior tracheal wall, causing ulceration and subsequent tracheal perforation. The perforation was bridged using a cuffed tracheostomy tube, but the patient subsequently died of additional comorbidities. Conclusions Our experience suggests that tracheal perforation should be considered when pediatric patients with tracheostomy tubes suddenly develop hypotension.

Abstract An integrated device capable of generating large number of multiplexed optical vortex beams with arbitrary topological charge is considered as one of the crucial requirement for driving information photonics forward. Here we report a simple method for simultaneous generation of 100 multiplexed optical vortex beams from a polymer film of size 1 mm2 and thickness of 30 μm. This is achieved through a combination of computer-generated holography, digital hologram printing and photoisomeric polymers. When the fabricated sample is illuminated with a collimated laser beam, a pre-determined vortex array with arbitrary topological charge is emitted. The polymer film easy to synthesize and exhibits a diffraction efficiency of 30% with a retention period longer than 50 days.

Abstract Large-area helix microstructures intended for metamaterials were fabricated using a negative photoresist, SU-8 using a two photon absorption direct laser writing (TPA-DLW). Two types of helix structures were fabricated. One type is those with no neighboring distance. In this case, compact helix structures with radius of 2.5 and 1.0 μm were fabricated. Another type is those with enough neighboring distance. The helix structures with shorter neighboring distance below 6.0 μm were collapsed, whereas those with longer neighboring distance more than 6.5 μm, free-standing helix structures could successfully be built. To stabilize the fabricated free-standing helix microstructures with a 1 μm radius, circular foundations with a radius of 1.3 μm and elevation angle of 10, 12, or 14° were built in advance. The foundation is useful to avoid collapsing the helix microstructures. Due to the useful foundation, over 18,000 helical structures were fabricated in a large area. The fabricated helical structures were coated with silver using an electroless plating method to produce 3D metallic helix structures. Silver coating was measured using a EDX measurement. The obtained helical structures have the potential for metamaterials to control the handedness of a circularly polarized infrared beam.

Abstract Background Hepatic metastasis of soft tissue sarcoma is rare compared to lung metastasis, and the literature is scarce. We examined the risk of hepatic metastasis according to the site of occurrence and histological type. Methods From a Hospital‐based Cancer Registry, 658 patients registered between 2007 and 2017 with soft tissue sarcomas were evaluated. The exclusion criteria were gastrointestinal stromal tumors, tumors of unknown origin, and follow‐up periods of less than 1 month. SPSS 25 was used for statistical analysis. Results The risk of hepatic metastasis was significantly higher in the retroperitoneum (HR, 5.981; 95% CI, 2.793‐12.808) and leiomyosarcoma (HR, 4.303; 95% CI, 1.782‐10.390). Multivariate analysis showed that the risk of hepatic metastasis as first distant metastasis was high in leiomyosarcoma (HR, 4.546; 95% CI, 2.275‐9.086) and retroperitoneal onset (HR, 4.588; 95% CI, 2.280‐9.231). The 2‐year survival rate after hepatic metastasis was 21.7%. Conclusions The onset of hepatic metastasis indicates a poor prognosis. However, hepatic metastasis from retroperitoneal sarcoma and leiomyosarcoma may be the first distant metastasis in some cases. For retroperitoneal sarcoma and leiomyosarcoma, additional screening for hepatic metastasis such as contrast CT should be considered during staging and follow‐up after treatment.

Summary: The XPC protein complex plays a central role in DNA lesion recognition for global genome nucleotide excision repair (GG-NER). Lesion recognition can be accomplished in either a UV-DDB-dependent or -independent manner; however, it is unclear how these sub-pathways are regulated in chromatin. Here, we show that histone deacetylases 1 and 2 facilitate UV-DDB-independent recruitment of XPC to DNA damage by inducing histone deacetylation. XPC localizes to hypoacetylated chromatin domains in a DNA damage-independent manner, mediated by its structurally disordered middle (M) region. The M region interacts directly with the N-terminal tail of histone H3, an interaction compromised by H3 acetylation. Although the M region is dispensable for in vitro NER, it promotes DNA damage removal by GG-NER in vivo, particularly in the absence of UV-DDB. We propose that histone deacetylation around DNA damage facilitates the recruitment of XPC through the M region, contributing to efficient lesion recognition and initiation of GG-NER.

Summary: Background: Physicians have had to perform numerous extubation procedures during the prolonged coronavirus disease 2019 (COVID 19) pandemic. Future pandemics caused by unknown pathogen may also present a risk of exposure to infectious droplets and aerosols. Aim: This study evaluated the ability of a newly developed aerosol barrier, “Extubation-Aerosol (EA)-Shield” to provide maximum protection from aerosol exposure during extubation via an aerosolised particle count and high-quality visualisation assessments. Methods: We employed a cough model having parameters similar to humans and used micron oil aerosol as well as titanium dioxide as aerosol tracers. Aerosol barrier techniques employing a face mask (group M) and EA-Shield (group H) were compared. Findings: The primary outcome was the difference in the number of particles contacting the physician's face before and after extubation. The maximum distances of aerosol dispersal after extubation were measured as the secondary outcomes. All aerosolised particles of the two tracers were significantly smaller in group H than in group M (p < 0.05). In addition, the sagittal and axial maximum distances and sagittal areas of aerosol dispersal for 3, 5, and 10 s after extubation were significantly smaller in group H than in group M (p < 0.05). Conclusion: This model indicates that EA-Shield could be highly effective in reducing aerosol exposure during extubation. Therefore, we recommend using it as an aerosol barrier when an infectious aerosol risk is suspected.

Laguerre–Gaussian beams are structured light beams with a donut-shaped symmetric intensity profile and a helical phase profile. The beam profile is defined by a quantized parameter known as the mode number which extends to infinity. The availability of unbounded modes makes these beams a promising candidate for next-generation optical computing, and optical communication technologies. The symmetric intensity profile of a Laguerre–Gaussian beam can be made asymmetric through certain techniques and these beams are known by the term ‘asymmetric Laguerre–Gaussian beams’. Here, the asymmetricity adds another degree of freedom to the beam (apart from its mode number) which helps in encoding more information compared to a symmetric beam. However, in order to harness the benefits of all the available degrees of freedom, it is required to generate a large number of such beams in a multiplexed fashion. Here, we report the generation of such a large array of asymmetric Laguerre–Gaussian beams for the first time. Computer-generated holography and spatial multiplexing techniques were employed to generate a large array comprising of 12 × 16 = 192 asymmetric Laguerre–Gaussian beams with an arbitrary mode index and asymmetricity.

The photocurrent for poly(4-(dimethylamino)benzyl acrylate) (PDAA) photorefractive composites with (4-(diphenylamino)phenyl)methanol (TPAOH) photoconductive plasticizers was measured to be two orders of magnitude higher than that obtained with (2,4,6-trimethylphenyl)diphenylamine (TAA) photoconductive plasticizers. In this study, to determine the reason for the large difference in the photocurrent measured for PDAA photorefractive composites containing two different photoconductive plasticizers of TPAOH and TAA, the highest occupied molecular orbital (HOMO) level identical to the ionization potential (Ip) and the width of the density of states (DOS) were evaluated using photoelectron yield spectroscopy, and the transient photocurrent was analyzed using a two-trap model. The estimated hole mobility was also rationalized using a Bässler formalism together with the energetic disorder of the width of the DOS and the positional disorder of the scattering situation for carrier hopping.

Abstract Fanconi anemia (FA) is a rare genetic disease characterized by the deficiency of the cellular response and repair pathway for DNA interstrand crosslink (ICL) damage. Although recent studies have revealed the detailed molecular functions of FA proteins encoded by 22 genes, the mechanism of occurrence of endogenous ICLs in the human body remains poorly understood. In this short review, we summarize the potential endogenous sources of ICLs counteracted by FA proteins, and provide perspectives on the unanswered questions regarding FA.

Abstract The preservation of marine ecosystems is one of the most severe challenges at present. In particular, oil‐water separation from oil spills and oily wastewater is important. For this reason, a low‐cost, effective, and sustainable polymeric solution is in high demand. In this work, a controlled‐wettability membrane for selective separation of oil‐water mixtures and emulsions is developed. The nanofibrous membrane is prepared via a facile and cost‐effective electrospinning technique using environmentally sustainable materials, such as recycled polyethylene terephthalate and chitosan. The effect of different concentrations of chitosan on the morphology, chemical composition, mechanical properties, wettability, and separation performance of the membrane is evaluated. The membranes exhibited underoil superhydrophobic and underwater superoleophobic behavior, which is essential to perform the selective separation. In fact, the designed filter has competitive antifouling properties (oil intrusion pressure > 45 kPa) and showed high heavy‐ and light‐oil/water separation efficiencies (>95%) both for emulsions and immiscible mixtures.

Ince–Gaussian beams, defined as a solution to a wave equation in elliptical coordinates, have shown great advantages in applications such as optical communication, optical trapping and optical computation. However, to ingress these applications, a compact and scalable method for generating these beams is required. Here, we present a simple method that satisfies the above requirement, and is capable of generating arbitrary Ince–Gaussian beams and their superposed states through a computer-generated hologram of size 1 mm2, fabricated on an azocarbazole polymer film. Other structural beams that can be derived from the Ince–Gaussian beam were also successfully generated by changing the elliptical parameters of the Ince–Gaussian beam. The orthogonality relations between different Ince–Gaussian modes were investigated in order to verify applicability in an optical communication regime. The complete python source code for computing the Ince–Gaussian beams and their holograms are also provided.

The energy storage properties of ferroelectric capacitors of nylon 10-12 were investigated. The energy density and the energy efficiency were determined at a high temperature of 90 °C. The normal hysteresis loop of displacement–electric field at room temperature decreased in width at 90 °C. An energy density (U) of 3.92 J cm−3 at 327 MV m−1 was measured for the melt-quenched sample and U of 3.86 J cm−3 at 383 MV m−1 for the annealed-quenched sample. No decrease in the energy efficiency was measured at increased electric fields. An energy efficiency of over 90% was measured for both samples.

Abstract Nucleotide excision repair (NER) is a versatile DNA repair pathway, which can remove an extremely broad range of base lesions from the genome. In mammalian global genomic NER, the XPC protein complex initiates the repair reaction by recognizing sites of DNA damage, and this depends on detection of disrupted/destabilized base pairs within the DNA duplex. A model has been proposed that XPC first interacts with unpaired bases and then the XPD ATPase/helicase in concert with XPA verifies the presence of a relevant lesion by scanning a DNA strand in 5′-3′ direction. Such multi-step strategy for damage recognition would contribute to achieve both versatility and accuracy of the NER system at substantially high levels. In addition, recognition of ultraviolet light (UV)-induced DNA photolesions is facilitated by the UV-damaged DNA-binding protein complex (UV-DDB), which not only promotes recruitment of XPC to the damage sites, but also may contribute to remodeling of chromatin structures such that the DNA lesions gain access to XPC and the following repair proteins. Even in the absence of UV-DDB, however, certain types of histone modifications and/or chromatin remodeling could occur, which eventually enable XPC to find sites with DNA lesions. Exploration of novel factors involved in regulation of the DNA damage recognition process is now ongoing.

Abstract Background Glycosylation is one of the major posttranslational modifications of proteins and it is essential for proteins to obtain normal biological functions. Congenital disorders of glycosylation (CDGs) are very rare genetic disorders that lack enzymes needed for glycosylation. Phosphomannomutase-2 (PMM2)-CDG is the most common type of CDG. CDGs can cause a wide variety of clinical symptoms in almost every organ system. Muscular hypotonia is often present in patients with CDGs and is one of the most notable problems for anesthetic management because the susceptibility to nondepolarizing neuromuscular blocking agents (NMBAs) in patients with CDGs is unknown. Case presentation The patient was a 17-month-old boy who weighed 6.5 kg and was 71 cm tall. He presented for strabismus surgery. He had muscular hypotonia, mental retardation, hepatic dysfunction, mild cerebellar hypoplasia, and some dysmorphic features including inverted nipples and abnormal subcutaneous fat distribution of the hips. Gene analysis revealed a compound heterozygous mutation in the gene encoding PMM2 and the patient was diagnosed as having PMM2-CDG. General anesthesia was performed with sevoflurane, nitrous oxide, and rocuronium. Neuromuscular monitoring was performed during anesthesia using train-of-four (TOF)-Watch® (MSD, Japan). As postoperative analgesia, the surgeon performed sub-Tenon’s anesthesia. We did not use any intravenous analgesic. After completion of the operation, residual rocuronium was competed by administration of sugammadex. The patient gained consciousness and spontaneous breathing was established shortly thereafter, and the trachea was smoothly extubated. He was transported to an inpatient ward and was discharged to his home the next day without any complication. Conclusions We performed safe anesthetic management in a 17-month-old boy with PMM2-CDG using rocuronium under neuromuscular monitoring. A patient with PMM2-CDG may show nearly normal susceptibility to nondepolarizing NMBAs.

A polystyrene (PS)-based fibrous color dosimeter, comprising a color former based on 2-(phenylamino)-6-(dipentylamino)-3-methylspiro[9H-xanthene-9,3′-phthalide] (Black305) fluoran leuco dye and a 2-(4-methoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine (MBTT) photoacid generator, was developed for visual detection of X-ray doses of 15 Gy and higher. The composite fiber was produced by using a centrifugal spinning method, and the obtained composite fiber exhibited a stable and uniform morphology with a fiber diameter of 10 μm or less and had sufficient mechanical strength. As an example of practical application, we successfully processed the composite fiber into an apron and clearly and visually confirmed that the color change from yellow to black occurs on the surface of the fabric under X-ray exposure.

This study investigated the efficiency of chitosan/polyethylene oxide (PEO)-based nanofibers with incorporated bioactive glass particles as a coating for titanium alloy, in order to improve the bacteriostatic behavior and, concurrently, promote the production of mineralized tissue. Nanofibers with and without bioglass powder were fabricated by electrospinning technique and characterized using several microscopic and spectroscopic techniques in order to study their morphological and physiochemical properties. Subsequently, the substrates were tested in vitro against Staphylococcus epidermidis and SaOS-2 human osteosarcoma cell line. After in vitro testing, viability and CFU counting assays combined with fluorescence microscopy showed a clear decrease in bacterial growth on all substrates with increasing time. However, this trend was stronger for substrates coated with nanofibers. Formation of mineralized matrix upon exposure to osteoblasts was confirmed by means of SEM/EDX and the content/distribution of osteocalcin and osteopontin estimated by fluorescence microscopy. Incorporation of bioglass promoted biomineralization and stimulated osteoblasts to produce a higher amount of bone extracellular matrix. The present results suggest that a chitosan/PEO/bioactive glass nanofiber composite applied as coating on titanium alloys could concurrently improve antibacterial and osteoconductive properties and could be a potential candidate for dental and orthopedic applications.

The Fanconi anemia (FA) pathway is critically involved in the maintenance of hematopoietic stem cells and the suppression of carcinogenesis. A key FA protein, FANCD2, is monoubiquitinated and accumulates in chromatin in response to DNA interstrand crosslinks (ICLs), where it coordinates DNA repair through mechanisms that are still poorly understood. Here, we report that CtIP protein directly interacts with FANCD2. A region spanning amino acids 166 to 273 of CtIP and monoubiquitination of FANCD2 are both essential for the FANCD2-CtIP interaction and mitomycin C (MMC)-induced CtIP foci. Remarkably, both FANCD2 and CtIP are critical for MMC-induced RPA2 hyperphosphorylation, an event that accompanies end resection of double-strand breaks. Collectively, our results reveal a role of monoubiquitinated FANCD2 in end resection that depends on its binding to CtIP during ICL repair.

We show the ferroelectric switching of a thin film of the copolymer of 60 mol% vinylidene fluoride and 40 mol% trifluoroethylene when it is subjected to a sinusoidal electric field from 10 Hz to 100 kHz using a conductive probe chip of AFM. A switching speed of 1.6 ×106 s-1 (switching time of 660 ns) was measured at 100 kHz switching.

RAD51 recombinase polymerizes at the site of double-strand breaks (DSBs) where it performs DSB repair. The loss of RAD51 causes extensive chromosomal breaks, leading to apoptosis. The polymerization of RAD51 is regulated by a number of RAD51 mediators, such as BRCA1, BRCA2, RAD52, SFR1, SWS1, and the five RAD51 paralogs, including XRCC3. We here show that brca2-null mutant cells were able to proliferate, indicating that RAD51 can perform DSB repair in the absence of BRCA2. We disrupted the BRCA1, RAD52, SFR1, SWS1, and XRCC3 genes in the brca2-null cells. All the resulting double-mutant cells displayed a phenotype that was very similar to that of the brca2-null cells. We suggest that BRCA2 might thus serve as a platform to recruit various RAD51 mediators at the appropriate position at the DNA-damage site.

Developing flexible conductive aerogels solely from polymers for pressure sensors frequently faces challenges due to balancing durable mechanical characteristics with responsive conductivity. Here, we introduce an economical and scalable approach to manufacture a compressible and flexible conductive aerogel designed for application in piezoresistive pressure sensors. In a dip-coating process, the conductive aerogel poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)@polyimide (PI) is produced by immersing the polyimide nanofibrous aerogel (PiNFA) in an aqueous dispersion of PEDOT:PSS. SEM, TEM, FTIR, and XPS analyses confirm the existence of a PEDOT:PSS coating on PiNFA without changing the cellular hierarchical microporous structure. PiNFA's porous interconnected structure enables the electrical PEDOT:PSS@PI to exhibit notable compressibility and retain a stable piezoresistive response even up to 80% of compressive strain with a maximum compressive stress of 250 kPa and a relative resistance variation of 96.10%, respectively. The sensitivity of the PEDOT:PSS@PI aerogel, represented by the gauge factor (GF), varies from 4.06 to 0.82 across the 0-80% compression strain range, showcasing its promising versatility for various pressure sensor applications. [ABSTRACT FROM AUTHOR]