Μm Range Research Articles

The porous system of a reverse osmosis membrane − operando studies with small-angle neutron scattering

This manuscript deals with operando small-angle neutron scattering (SANS) on a reverse osmosis (RO) thin film composite (TFC) membrane, which was exposed to salt-free water at a transmembrane pressure of 25 bar and a transverse flow rate of 18 L/h. Permeate flux and electric conductivity were detected in parallel to SANS. The relevant objects of investigation are macro- and nanopores in the range of μm and nm, which were investigated with two SANS diffractometers covering a scattering vector Q between 10-4 and 0.3 Å−1. Salt-free water isotopes of H2O and D2O and their mixtures were used for the purpose of contrast matching, thereby determining the size of pores in the membrane layers. Macropores of the order of μm dimension were found in the nonwoven polypropylen (PP) layer showing a decline in size between 2 and 2.5 % over the experimental time of 7 to 17 h. The macropores of the polysulfone layer (PSU) have a size of about 0.4 μm. Nanopores with an average total diameter of (23.7 ± 0.5) Å of volume fraction of the order of 2 % vol are found exclusively in the PSU layer. The pore morphology was compared with the results of local methods such as SEM and TEM tomography, showing the complementarity of these methods and their necessity for a more complete picture of membrane morphology. A correlation between permeate flux and SANS parameter is discussed.

Degradable biporous polymeric networks based on 2-methylene-1,3-dioxepane: Towards hierarchically structured materials meant for biomedical applications

For the first time, the preparation of doubly porous “poly(ε-caprolactone)-like” networks through free-radical ring-opening copolymerization of 2-methylene-1,3-dioxepane with divinyl adipate was achieved via a double porogen templating approach. This versatile strategy allowed for the formation of macropores of around 150 μm generated by removal of sieved and sintered NaCl particles in water, while smaller pores in the 1–10 μm range were created by phase separation during the copolymerization process through a syneresis mechanism in the presence of a porogenic solvent. The chemical nature of the as-obtained scaffolds was evidenced by Raman spectroscopy. The two distinct porosity levels could be examined by scanning electron microscopy and mercury intrusion porosimetry. The nature of the porogenic solvent as well as its volume proportion and the amount of crosslinking agent in the polymerization feed allowed for finely tuning the porous features of the micropores. The crucial role of the double porosity of such biporous scaffolds on their water uptake and mechanical properties under compression was assessed by comparing them with their monoporous analogues, while their degradability was investigated in different alkaline aqueous media. The double porosity enabled a synergistic effect regarding the water uptake of the resulting scaffolds when compared to their monoporous counterparts. Doubly porous polymeric materials with appropriate mechanical properties were obtained, possessing high compressibility and shape memory behavior upon consecutive compression cycles. Finally, these materials display degradation rates that could be controlled depending on medium pH.

Chalcogenide mid‐infrared 3 × 1 fiber combiner for highly efficient 2–5 µm power and wavelength combining

AbstractFiber combiner is an effective device to enhance the power level or broaden the spectral wavelengths through a single monolithic output aperture, by fusing multiple fibers together. This is particularly important in mid‐infrared (MIR) 2–5 µm range, in which the output power of a single laser is limited. Due to the high MIR transmission, chalcogenide glass is an ideal host for constructing MIR fiber combiner. In this study, we report the design, fabrication, and characterization of a homemade 3 × 1 chalcogenide glass fiber combiner. The fiber combiner includes a 3 × 1 As–S input fiber bundle and an output fiber. The input fiber bundle was made by tapering three As–S multimode fibers with a core diameter of 200 µm and a cladding diameter of 250 µm. The taper reduction ratio R was 2, and the length of the taper transition region was ∼2 cm. The output fiber with core diameter of 360 µm and cladding diameter of 570 µm was then spliced with the tapered end of the fiber bundle. The total length of the combiner was ∼53 cm. The measurement of power combination at 4.56 µm indicated that the transmission efficiency of three ports reached 80%, whereas the power combining efficiency of the combiner was measured to be ∼48%. In addition, efficient wavelength combining over one octave has been demonstrated, by launching three different lasers at 2.1, 3.39, and 4.56 µm through the 3 × 1 combiner. It proves that chalcogenide fiber combiner is promising for the applications of high‐level power combination and broadband wavelength combining in MIR 2–5 µm range.

Intraoperative variability of corneal epithelium thickness in photorefractive keratectomy

PurposeTo evaluate the intraoperative central corneal epithelial thickness (ET) as measured by optical coherence pachymetry (OCP) in myopic eyes undergoing alcohol-assisted photorefractive keratectomy (PRK).MethodsA retrospective review of patients who underwent alcohol-assisted PRK was performed. Data were abstracted on age, gender, contact lens (CL) wear, preoperative refractive errors, keratometry, topographic and ultrasonic pachymetry, and intraoperative OCP measurements before and after epithelium removal. The central ET was calculated by subtracting OCP measurement after epithelium removal from the OCP measurement prior to epithelium removal.ResultsThe study comprised of 162 consecutive eyes from 81 patients. Mean age was 26.73 ± 6.47 years, 50.6% were males. CL was used in 92 eyes (56.8%). The mean sphere and spherical equivalent were −3.60 ± 1.84 D and −3.26 ± 1.85D, respectively. The mean intraoperative ET was 58.22 ± 17.53 µm (range, 15–121µm). Fifty-five percent of the eyes had an ET measurement above or below the range of 40-60µm. ET was significantly higher in the second operated eye compared to the first operated eye (p = 0.006), and an association was found to CL-wear (p = 0.03). There was no significant difference in thickness between genders (p = 0.62), and no correlation to patient age (p = 0.45, rp = 0.06), refractive errors (p > 0.30,rp=−0.07–0.08), nor keratometry(p > 0.80, rp=−0.01− (−0.02)).ConclusionThe intraoperative assessment of ET in alcohol-assisted PRK showed a high variability of the central corneal epithelium, with a significant difference between the first and second operated eyes. This difference may have implications when the epithelium is not included in the surgical planning in surface ablation.

JWST Observations of Young protoStars (JOYS)

Context. Accretion and ejection dictate the outcomes of star and planet formation processes. The mid-infrared (MIR) wavelength range offers key tracers of processes that have been difficult to detect and spatially resolve in protostars until now. Aims. We aim to characterize the interplay between accretion and ejection in the low-mass Class I protobinary system TMC1, comprising two young stellar objects: TMC1-W and TMC1-E at a 85 au separation. Methods. Using the James Webb Space Telescope (JWST) Mid-Infrared Instrument (MIRI) observations in 5–28 μm range, we measured the intensities of emission lines of H2, atoms, and ions, for instance, the [Fe II] and [Ne II], and HI recombination lines. We analyzed the spatial distribution of the different species using the MIRI Medium Resolution Spectrometer (MRS) capabilities to spatially resolve emission at 0″​​.2–0″​​.7 scales. we compared these results with the corresponding Atacama Large Millimeter/submillimeter Array (ALMA) maps tracing cold gas and dust. Results. We detected H2 outflow coming from TMC1-E, with no significant H2 emission from TMC1-W. The H2 emission from TMC1-E outflow appears narrow and extends to wider opening angles with decreasing Eup from S(8) to S(1) rotational transitions, indicating the disk wind as its origin. The outflow from TMC1-E protostar shows spatially extended emission lines of [Ne II], [Ne III], [Ar II], and [Ar III], with their line ratios consistent with UV radiation as a source of ionization. With ALMA, we detected an accretion streamer infalling from > 1000 au scales onto the TMC1-E component. The TMC1-W protostar powers a collimated jet, detected with [Fe II] and [Ni II], making it consistent with energetic flow. A much weaker ionized jet is observed from TMC1-E, and both jets appear strikingly parallel to each other, indicating that the disks are co-planar. TMC1-W is associated with strong emission from hydrogen recombination lines, tracing the accretion onto the young star. Conclusions. MIRI-MRS observations provide an unprecedented view of protostellar accretion and ejection processes on 20 au scales. Observations of a binary Class I protostellar system show that the two processes are clearly intertwined, with accretion from the envelope onto the disk influencing a wide-angle wind ejected on disk scales. Finally, the accretion from the protostellar disk onto the protostar is associated with the source launching a collimated high-velocity jet within the innermost regions of the disk.

Characterization of atmospheric pressure plasma deposited (APPD) coatings to improve the friction behavior of thermoplastic surfaces

Achieving a significant friction reduction is crucial for using thermoplastic materials as substrates in tribological applications and presents an eligible alternative to the use of light metals. In this study, previously developed MoS2/graphite/zinc composite coatings, applied by an atmospheric pressure plasma deposition (APPD) process, were investigated to extend the understanding of their characteristics and the influence of the process and environmental parameters on friction behavior. Tribological tests were conducted in ambient conditions and at elevated temperatures (110 °C) to study the friction behavior under application-oriented conditions. The presence of atmospheric oxygen during the deposition process was shown to influence the durability of the coatings, which motivated the application of an inert gas atmosphere for the coating deposition. A novel shrouding plasma nozzle was introduced, which further lowered the friction coefficients. The oxidizing effect of the plasma spray deposition was studied with X-ray photoelectron spectroscopy to investigate the strong impact of the deposition current on the friction behavior and durability of the deposited coatings. Coating composition, morphology, and the effects of the tribological testing were evaluated using optical microscopy, 3D surface measurements, scanning electron microscopy, X-ray diffraction, and nanoindentation. The fabricated coatings with thicknesses in the 10 μm range and good adhesion on the polyamide substrate were stable under extended testing durations and at elevated temperatures and accomplished a significant friction reduction compared to the uncoated polyamide. Thus, APPD-fabricated MoS2/graphite/zinc coatings represent an excellent candidate for low-friction applications of thermoplastic substrates.

Normal spectral emissivity measurement study of high-temperature alloy (316L) at 673–1273 K with a thermal oxidation surface

One effective approach to better understanding the performance characteristics of high-temperature alloys is to study their thermal oxidation behavior, and to accurately determine their spectral emissivity is helpful for increasing the accuracy of temperature measurements. Using a self-developed high-temperature emissivity testing system, the normal spectral emissivity across the range 673–1273 K and a spectral band of 1–14 μm was measured relative to this background radiation. The normal spectral emissivity of 316L high-temperature alloy was investigated during the thermal oxidation process. The change in emissivity of 316L high-temperature alloy during thermal oxidation was observed. The emissivity of the 316L high-temperature alloy undergoes great changes during thermal oxidation; for example, at 1273 K it was 0.055 in its un-oxidized state but after 50 h’ thermal oxidation went up to 0.829. Below 1073 K the emissivity of 316L high-temperature alloy in 8–14 μm range showed little change, making it ideal for radiation thermometry. By fitting the measurement data, we derived that the emissivity of 316L high-temperature alloy has an exponential relationship with thermal oxidation temperature, and is a power function relationship with thermal oxidation time.

Synthesis and Characterisation of Core-Shell Microparticles Formed by Ni-Mn-Co Oxides.

In this work, core and core-shell microparticles formed by Ni-Mn-Co oxides with controlled composition were fabricated by an oxalate-assisted co-precipitation route, and their properties were analysed by diverse microscopy and spectroscopy techniques. The microparticles exhibit dimensions within the 2-6 μm range and mainly consist of NiO and NiMn2O4, the latter being promoted as the temperature of the treatment increases, especially in the shell region of the microparticles. Aspects such as the shell dimensions, the vibrational modes of the spinel compounds primarily observed in the shell region, the oxidation states of the cations at the surface of the microparticles, and the achievement of a Ni-rich 811 core and a Mn-rich 631 shell were thoroughly evaluated and discussed in this work.

N-Hydroxypiridinedione: A Privileged Heterocycle for Targeting the HBV RNase H.

Hepatitis B virus (HBV) remains a global health threat. Ribonuclease H (RNase H), part of the virus polymerase protein, cleaves the pgRNA template during viral genome replication. Inhibition of RNase H activity prevents (+) DNA strand synthesis and results in the accumulation of non-functional genomes, terminating the viral replication cycle. RNase H, though promising, remains an under-explored drug target against HBV. We previously reported the identification of a series of N-hydroxypyridinedione (HPD) imines that effectively inhibit the HBV RNase H. In our effort to further explore the HPD scaffold, we designed, synthesized, and evaluated 18 novel HPD oximes, as well as 4 structurally related minoxidil derivatives and 2 barbituric acid counterparts. The new analogs were docked on the RNase H active site and all proved able to coordinate the two Mg2+ ions in the catalytic site. All of the new HPDs effectively inhibited the viral replication in cell assays exhibiting EC50 values in the low μM range (1.1-7.7 μM) with low cytotoxicity, resulting in selectivity indexes (SI) of up to 92, one of the highest reported to date among HBV RNase H inhibitors. Our findings expand the structure-activity relationships on the HPD scaffold, facilitating the development of even more potent anti-HBV agents.

Comparison of Lightning Channel Luminosity Versus Time Profiles in the Infrared and Visible Ranges

AbstractInfrared (IR) luminosity of lightning channel in the 3–5 μm range usually persisted throughout the entire interstroke interval, which is in contrast to the simultaneously recorded visible (0.4–0.8 μm) luminosity that always decayed to an undetectable level prior to a subsequent return stroke pulse. A longer visible luminosity period at the end of flash tended to be associated with a longer IR afterglow period following the decay of visible luminosity (and by inference current) to an undetectable level. At the end of flash, the IR luminosity persisted up to about 1 s, and the median IR afterglow duration was a factor of 10 longer than the median visible luminosity duration. The IR luminosity often exhibited a hump when the visible luminosity was monotonically decaying or undetectable, with the corresponding channel temperature being likely around 3400 K.

Dimensions of muddy brown granular casts in patients with acute tubular injury

BackgroundThe presence of “muddy” brown granular casts (MBGC) in the urine sediment is pathognomonic for acute tubular injury (ATI). Although MBGC have been noted for years, there are no reports regarding their length nor width. The objective of this study was to measure MBGC using images obtained by light microscopy and investigate associations with clinically relevant parameters. MethodsPatients with diagnosis of ATI as evidenced by visualization of abundant MBGC (>30% low power fields) were sampled. Bright-field images were measured using ImageJ. Twenty-five patients were included: 44% women; median age 64 yrs; 52% white, 36% black. Mean MBGC width (n = 350) was 34.4 ± 13.1 µm (range: 9 to 110 µm). ResultsMean MBGC length was 98.7 ± 42.7 µm (range: 33 to 317 µm). Based on a previous report of cortical tubular diameters, MBGC width corresponded well with the median reported range. MBGC width was positively correlated with patient height (ρ=0.41, p=0.04), and length was positively correlated with fractional excretion of sodium (ρ=0.57. p=0.02) and urine chloride concentration (ρ=0.90, p=0.001). Mean MBGC length was negatively correlated with age (ρ=-0.47, p=0.02) and urine phosphate concentration (ρ=-0.72, p=0.03). There were no differences between cases that required renal replacement therapy (RRT, n =10) and those that did not require RRT (n=15). ConclusionThis is the first study reporting dimensions of MBGC from cases with ATI. Clinical implications of these observations require further study.

Raspberry-shaped ZIF-8/Au nanozymes with excellent peroxidase-like activity for simple and visual detection of glutathione.

Artificial enzymes with high stability, adjustable catalytic activity, controllable preparation, and good reproducibility have been widely studied. Noble metal nanozymes, particularly gold nanoparticles (Au NPs), exhibit good catalytic activity, but their stability is poor. In this study, zeolitic imidazolate framework-8 (ZIF-8) was used as a carrier for Au NPs, thus improving the utilization efficiency and conservation stability of the nanozymes. A ZIF-8/Au nanocomposite with peroxidase activity and a raspberry-shaped structure was synthesized. In the assay, ZIF-8/Au catalyzed the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to a blue product oxidized TMB (oxTMB). Glutathione (GSH) selectively inhibited this reaction, with a detection limit of 0.28µM and linear range of 0.5-60µM. Using the photo and chromaticity analysis functions, we developed a portable analysis method using a smartphone equipped with a camera module as a detection terminal for a wide range of rapid screening techniques for GSH. Preparation of raspberry-shaped ZIF-8/Au improved the catalytic activity of Au NPs and good results were demonstrated in serum, which suggests their promising application under physiological conditions.

Surface decorated graphene oxide with porphyrin: A promising on-off sensor for Mn2+ ions detection in aqueous media

In this study, meso‑tetrakis(4-carboxyphenyl)porphyrin (TCPP) was chemically bonded to the surface of graphene oxide (GO) nanosheets and characterized by various techniques. The sensing prowess of the prepared composite towards metal ions was investigated through photoluminescence (PL) spectroscopy. Our results indicate that TCPP-GO can detect Mn2+ ions through fluorescence quenching. Therefore, experiments related to concentration, selectivity, detection limit, and response time were conducted to study the performance of the TCPP-GO sensor. A linear response of fluorescence intensity of TCPP-GO and Mn2+ in the 25–270 μM range with a detection limit of 1.8 μM was observed. The competition test displayed that the presence of other ions such as Sn2+, Pt2+, Ca2+, Na+, Fe3+, Fe2+, Zn2+, Cu2+, Cr2+, Co2+, Ni2+ had no significant effect on detecting Mn2+ ions. Furthermore, the suggested sensor demonstrated excellent performance for sensing manganese ions in real water samples.

Process development and validation of next generation 3D calibration standards for application in optical microscopy

Abstract A scalable wafer-based fabrication process for a new generation of 3D standards enabling the 3D calibration of optical microscopes is presented and validated. The 3D standards are based on step pyramids with several layers in the µm range and a system of cylindrical knops distributed across the layers as marks for coordinate based calibration. This enables calibration for the three coordinate axes and the orthogonality error between them in a single measurement step. The requirements necessary for such a calibration, as optical non-transparency, reproducible flatness of the pyramid step heights and the lowest possible deviations of the lateral marks coordinates, are met by optimizing the manufacturing process: The deviation of the height steps distributed over the wafer is ±3.6 nm and is primarily caused by the layer deposition processes. The lateral manufacturing accuracy was determined using calibrated scanning electron microscope (SEM) and show a mean deviation of 20 or 60 nm, depending on the lateral size of the structures. The electron beam lithography process and the level of inaccuracy of the SEM standard have an influence on the lateral scaling accuracy. Based on the tactilely generated height values and the coordinates of the mark determined by a calibrated SEM, an example calibration of a confocal laser scanning microscope was successfully performed and showed good conformity to conventional calibration techniques.

Characterization of the BCMA epitope bound by BCMA-CD3 T cell engager elranatamab.

7546 Background: Elranatamab is a BCMA-CD3 bispecific antibody with an accelerated approval in the US and EU for relapsed/refractory multiple myeloma (RRMM). Elranatamab binds to CD3 on T cells and BCMA on MM tumor cells; this dual binding results in T cell activation, cytokine release, and tumor cell killing. Engagement of the BCMA surface receptor by its ligands, APRIL and BAFF, mediates plasma cell proliferation and survival. Elevated BCMA, as well as BAFF and APRIL are present in MM patients, yet in vitro functional assays have shown physiologically relevant soluble APRIL or BAFF concentrations did not significantly impact elranatamab activity. Moreover, emerging clinical data from relapsed patients has identified novel, yet relatively rare BCMA protein mutations that may impact BCMA ligand or targeted modality binding. Here we characterized the BCMA binding affinity, evaluated the impact on BCMA binding to BAFF and APRIL interactions, and identified the BCMA binding epitope. We also generated a model from crystal structure data to map reported BCMA mutations identified in patients. Methods: Elranatamab binding affinity to recombinant human BCMA and characterization of BAFF and APRIL interactions with elranatamab-bound BCMA were calculated via SPR at 37˚C with a classical sandwich format. The elranatamab BCMA binding epitope was identified by a co-crystal structure with a parental anti-BCMA Fab that has identical CDR sequences to elranatamab. Alpha-fold modeling was used to map identified BCMA mutations on the antibody/BCMA interface. Results: Elranatamab binds to BCMA with higher affinity (~38 pM) compared to reported binding affinities of BAFF (μM range) and APRIL (nM range) ligands. The identified elranatamab epitope largely overlaps with known ligand epitopes, supporting that elranatamab higher affinity BCMA binding blocks ligand binding. Alpha fold modeling of four recently reported rare BCMA mutations shows that they lie along the binding interface. Conclusions: Due to its high affinity for BCMA, elranatamab potency is unlikely to be impacted by elevated levels of soluble BAFF or APRIL in RRMM patients. Future studies are needed to characterize the impact of emerging MM patient BCMA mutations on the binding and function of anti-BCMA targeting modalities, particularly given the small extracellular domain of BCMA available for therapeutic targeting and the highly overlapping binding epitopes reported for approved BCMA agents.

Retinal and Vitreous Changes Associated with Spontaneous Improvement in Myopic Macular Schisis

PurposeTo describe the retinal and vitreous changes in eyes showing myopic macular schisis (MMS) improvement when vitrectomy was not performed and identify triggering factors. DesignRetrospective observational study. SubjectsPatients with non-operated myopic macular schisis MethodsThe records of patients with MMS who were followed without performing surgery for more than 6 months were retrospectively reviewed, and the eyes showing an anatomical improvement were included. MMS evolution was analyzed quantitatively (central foveal thickness [CFT], parafoveal thickness, maximum height) and qualitatively (presence/absence of foveal detachment, lamellar hole, epiretinal membrane, choroidal neovascularization, inner and outer retinoschisis, vitreous status) at baseline and at the final visit. An anatomical improvement was defined as a decrease in CFT by at least 50 μm. Main outcome measureThe rate anatomical improvement of MMS without performing vitrectomy and the morphological changes observed in these cases. ResultsIn a cohort of 74 non-operated eyes with MMS, MMS improved in 14 eyes (19%) after a mean follow-up of 55 ± 38 months (range: 8-138). In these improved cases, the mean decrease in CFT was 153 ± 166 μm (range: 24-635, p=0.005) and a complete resolution of MMS was observed in 9 eyes (64%). In 9 eyes (64%), the improvement was associated with visible vitreous changes in the macular area on the OCT scans. The mean visual acuity, which was already good at baseline (20/50, 0.4 ± 0.2 LogMAR), increased at the last visit (20/40, 0.3 ± 0.3 LogMAR) but without reaching significance. ConclusionThis long-term follow-up analysis showed that almost 20% of MMS in eyes without indication for surgery could improve over time. In most cases, the improvement was associated with an apparent resolution of vitreous tensions.

Colorimetric/fluorescent dual-mode assay for antioxidant capacity of gallnuts based on CuCo nanozyme and AIE luminogen

In this work, we present a dual-mode assay system consisting of a nanozyme and a luminogen with the aggregation-induced emission (AIE) feature. In the assay system, the chosen nanozyme named CuCo-0 catalyzes the substrate to produce colorimetric signals, while the aggregates of H4ETTC (4,4′,4″,4‴-(ethene-1,1,2,2-tetrayl) tetrakis ([1,1′-biphenyl]-4-carboxylic acid), a typical AIE luminogen, generate fluorescent signals. The peroxidase-like activity of the CuCo-0 nanozyme can be remarkably suppressed with sequential additions of antioxidants, leading to a dual-signal response characterized by enhanced fluorescence emission and reduced UV-vis absorbance. On this basis, a dual-mode assay capable of producing both colorimetric and fluorescent signals for the assessment of antioxidant capacity using gallic acid as a representative antioxidant was exploited. Good linearity can be obtained in the 0–60 μM range for both colorimetric analysis and fluorescent analysis, with detection limits of 1.3 μM and 0.35 μM, respectively. Furthermore, this dual-mode assay was successfully applied to real gallnut samples, yielding satisfactory results.

Novel 4-[4-(4-methylpiperazin-1-yl)phenyl]-6-arylpyrimidine derivatives and their antitrypanosomal activities against T.brucei

Human African trypanosomiasis, or sleeping sickness, is a neglected tropical disease caused by Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense and is invariably fatal unless treated. Current therapies present limitations in their application, parasite resistance, or require further clinical investigation for wider use. Our work, informed by previous findings, presents novel 4-[4-(4-methylpiperazin-1-yl)phenyl]-6-arylpyrimidine derivatives with promising antitrypanosomal activity. In particular, 32 exhibits an in vitro EC50 value of 0.5 µM against Trypanosoma brucei rhodesiense, and analogues 29, 30 and 33 show antitrypanosomal activities in the <1 µM range. We have demonstrated that substituted 4-[4-(4-methylpiperazin-1-yl)phenyl]-6-arylpyrimidines present promising antitrypanosomal hit molecules with potential for further preclinical development.

Optimal Treatment of Tumor in Upper Human Respiratory Tract Using Microaerosols.

Lung cancer is a frequently diagnosed respiratory disease caused by particulate matter in the environment, especially among older individuals. For its effective treatment, a promising approach involves administering drug particles through the inhalation route. Multiple studies have investigated the flow behavior of inhaled particles in the respiratory airways of healthy patients. However, the existing literature lacks studies on the precise understanding of the transportation and deposition (TD) of inhaled particles through age-specific, unhealthy respiratory tracts containing a tumor, which can potentially optimize lung cancer treatment. This study aims to investigate the TD of inhaled drug particles within a tumorous, age-specific human respiratory tract. The computational model reports that drug particles within the size range of 5-10 μm are inclined to deposit more on the tumor located in the upper airways of a 70-year-old lung. Conversely, for individuals aged 50 and 60 years, an optimal particle size range for achieving the highest degree of particle deposition onto upper airway tumor falls within the 11-20 μm range. Flow disturbances are found to be at a maximum in the airway downstream of the tumor. Additionally, the impact of varying inhalation flow rates on particle TD is examined. The obtained patterns of airflow distribution and deposition efficiency on the tumor wall for different ages and tumor locations in the upper tracheobronchial airways would be beneficial for developing an efficient and targeted drug delivery system.

A Pyrene Coupled Azaine-linkage Chromo-fluorogenic Probe for Specific Detection of Sarin Gas Stimulant, Diethylchlorophosphate.

Owing to the extreme toxicity and easy synthesis protocol of G-series nerve agents, developing an efficient sensor for selective detection is necessary. Although various traditional methods are utilized to identify these nerve agents, chromo-fluorogenic probes have gained attractive attention from the scientific communities. In the present contribution, we have introduced a new symmetrical aza-substituted chromo-fluorogenic sensor, BPH, for specific detection of sarin gas, one of the fatal G-series nerve agents surrogate, diethylchlorophosphate (DCP). BPH shows a noticeable naked eye colorimetric change from pale yellow to light pink in the presence of DCP, displaying highly intense bright greenish cyan color photoluminosity under a 365nm UV lamp,which is also manifested from the color chromaticity diagram. A BPH-staining paper stirps-based test kit experiment has been demonstrated for the on-site detection of nerve agent mimics. A more attractive and efficient application of BPH as a sarin gas vapor phase sensor mimics DCP in solid and solution phases. The BPH-based chromo-fluorogenic sensor shows excellent selectivity toward DCP with a detection and quantification limit in the µM range. This report invokes a new way for the researchers to detect DCP employing a simple chromo-fluorogenic sensor, which could be prepared by a time-saving,straightforward, handy protocol from the cost-effective starting materials.