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We study the spatial dependence of the mobility of microparticles diffusing close to an edge of a square microtube. Confocal particle tracking is used to measure the local diffusion coefficients of fluorescent latex 1.1μm particles suspended in an aqueous solution in a borosilicate square capillary of 50μm section side. Observations are made for a set of planes obtained by confocal sectioning of the capillary volume. The translational diffusion coefficients parallel to the axis channel and perpendicular to one of the walls are measured as a function of the distance from both the two channel walls concurring in an edge. A complete 3D spatial map of the colloid diffusion coefficients is thus obtained. Near the corner, the diffusion is hindered up to about 40% as compared to its bulk value. The three translational diffusion coefficients pertaining to the motions along the channel axis and within the channel cross-section turn out to be different from each other and differently affected by the confinement, i.e., we are in the presence of an anisotropic diffusion. The hindered diffusion phenomenon is also examined by finite element numerical simulations, and the numerical predictions fairly agree with the measured diffusion coefficients., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Reprimo (RPRM), a downstream effector of p53-induced cell cycle arrest at G2/M, has been proposed as a putative tumor suppressor gene (TSG) and as a potential biomarker for non-invasive detection of gastric cancer (GC). The aim of this study was to evaluate the epigenetic silencing of RPRM gene by promoter methylation and its tumor suppressor function in GC cell lines. Furthermore, clinical significance of RPRM protein product and its association with p53/p73 tumor suppressor protein family was explored. Epigenetic silencing of RPRM gene by promoter methylation was evaluated in four GC cell lines. Protein expression of RPRM was evaluated in 20 tumor and non-tumor matched cases. The clinical significance of RPRM association with p53/p73 tumor suppressor protein family was assessed in 114 GC cases. Tumor suppressor function was examined through functional assays. RPRM gene expression was negatively correlated with promoter methylation (Spearman rank r = -1; p = 0.042). RPRM overexpression inhibited colony formation and anchorage-independent growth. In clinical samples, RPRM gene protein expression was detected in 75% (15/20) of non-tumor adjacent mucosa, but only in 25% (5/20) of gastric tumor tissues (p = 0.001). Clinicopathological correlations of loss of RPRM expression were significantly associated with invasive stage of GC (stage I to II-IV, p = 0.02) and a positive association between RPRM and p73 gene protein product expression was found (p<0.0001 and kappa value = 0.363). In conclusion, epigenetic silencing of RPRM gene by promoter methylation is associated with loss of RPRM expression. Functional assays suggest that RPRM behaves as a TSG. Loss of expression of RPRM gene protein product is associated with the invasive stage of GC. Positive association between RPRM and p73 expression suggest that other members of the p53 gene family may participate in the regulation of RPRM expression.

Background: As tumor burden increases in colorectal cancer, treatment complexity progresses from colectomy to hepatectomy and lastly to cytoreductive surgery with heated intraperitoneal chemotherapy (CRS-HIPEC). The aim of this study was to evaluate whether disparities exist in the access to progressively more complex surgical treatment options., Methods: Patients undergoing surgery for colorectal cancer were grouped by treatment type: group 1 (n = 224) underwent colectomy for nonmetastatic disease, group 2 (n = 112) underwent hepatectomy for liver metastasis, and group 3 (n = 112) underwent CRS-HIPEC for carcinomatosis., Results: Whites were predominant in the HIPEC group (71.4 %) compared to the hepatectomy (67.9 %) and colectomy (57.6 %) groups (p = 0.025). The majority of the privately insured patients were in the HIPEC group (70.5 %) compared to the hepatectomy (56.2 %) and colectomy (30.4 %) groups (p < 0.0001). Distance traveled to the hospital was farthest on average in the HIPEC group (104.6 ± 258.3 km) compared to the hepatectomy (29.0 ± 28.0 km) or colectomy (26.4  ± 66.2 km) group (p < 0.0001). Mean household income also varied between the three groups, with HIPEC patients earning $56,957 (±24,124), hepatectomy patients earning $56,999 (±28,588), and colectomy patients earning ($51,518 ± 24,201) (p = 0.0503) on average per year. The HIPEC cohort contained a higher proportion of English speakers (90.2 %) than the other groups (hepatectomy 87.9 %, colectomy 85.3 %); however, this difference was not statistically significant (p = 0.43)., Conclusions: CRS-HIPEC is not accessed equally across all socioeconomic groups. Patients undergoing HIPEC were most often white, English speaking, and privately insured; had a higher mean income; and had traveled the greatest distances on average to access surgical care.

The deflection of magnetic beads in a microfluidic channel through magnetophoresis can be improved if the particles are somehow focused along the same streamline in the device. We design and fabricate a microfluidic device made of two modules, each one performing a unit operation. A suspension of magnetic beads in a viscoelastic medium is fed to the first module, which is a straight rectangular-shaped channel. Here, the magnetic particles are focused by exploiting fluid viscoelasticity. Such a channel is one inlet of the second module, which is a H-shaped channel, where a buffer stream is injected in the second inlet. A permanent magnet is used to displace the magnetic beads from the original to the buffer stream. Experiments with a Newtonian suspending fluid, where no focusing occurs, are carried out for comparison. When viscoelastic focusing and magnetophoresis are combined, magnetic particles can be deterministically separated from the original streamflow to the buffer, thus leading to a high deflection efficiency (up to ~96%) in a wide range of flow rates. The effect of the focusing length on the deflection of particles is also investigated. Finally, the proposed modular device is tested to separate magnetic and non-magnetic beads.

Objectives: Liver biopsy diagnosis of primary sclerosing cholangitis (PSC) is difficult. We performed a detailed histologic analysis of PSC cases using novel bioinformatics analysis to identify histologic features that may be useful in its diagnosis., Methods: PSC liver explants were examined and compared with primary biliary cirrhosis and hepatitis C explants to act as controls. Demographic, macroscopic, and histologic variables were analyzed using both conventional statistics and an integrative bioinformatics approach, significance analysis of microarrays (SAM), and hierarchical clustering analysis (HCA)., Results: The PSC group was younger and had distinctive PSC features, including bile duct scars, onion-skin fibrosis, and arterial fibrointimal hyperplasia. SAM allowed the integration of variables by comparing PSC and control groups, whereas HCA was able to correctly categorize each group., Conclusions: This study demonstrates characteristic PSC histology as well as arterial hyperplasia to be distinctive features that may aid in PSC diagnosis and be confirmed by bioinformatics., (Copyright© by the American Society for Clinical Pathology.)

A novel method to estimate the relaxation time of viscoelastic fluids, down to milliseconds, is here proposed. The adopted technique is based on the particle migration phenomenon occurring when the suspending viscoelastic fluid flows in microfluidic channels. The method is applied to measure the fluid relaxation times of two water-glycerol polymer solutions in an ample range of concentrations. A remarkable improvement in the accuracy of the measure of the relaxation time is found, as compared with experimental data obtained from shear or elongational experiments available in the literature. Good agreement with available theoretical predictions is also found. The proposed method is reliable, handy and does not need a calibration curve, opening an effective way to measure relaxation times of viscoelastic fluids otherwise not easily detectable by conventional techniques.

Gastric cancer is the fifth most common cancer and the third leading cause of cancer-related death, whose patterns vary among geographical regions and ethnicities. It is a multifactorial disease, and its development depends on infection by Helicobacter pylori (H. pylori) and Epstein-Barr virus (EBV), host genetic factors, and environmental factors. The heterogeneity of the disease has begun to be unraveled by a comprehensive mutational evaluation of primary tumors. The low-abundance of mutations suggests that other mechanisms participate in the evolution of the disease, such as those found through analyses of noncoding genomics. Noncoding genomics includes single nucleotide polymorphisms (SNPs), regulation of gene expression through DNA methylation of promoter sites, miRNAs, other noncoding RNAs in regulatory regions, and other topics. These processes and molecules ultimately control gene expression. Potential biomarkers are appearing from analyses of noncoding genomics. This review focuses on noncoding genomics and potential biomarkers in the context of gastric cancer and the gastric precancerous cascade.

We present a theoretical investigation of the anomalous ferroelectricity of mixed-stack charge transfer molecular crystals, based on the Peierls-Hubbard model, and first-principles calculations for its parametrization. This approach is first validated by reproducing the temperature-induced transition and the electronic polarization of TTF-CA, and then applied to a novel series of hydrogen-bonded crystals, for which room temperature ferroelectricity has recently been claimed. Our analysis shows that the hydrogen-bonded systems present a very low degree of charge transfer and hence support a very small polarization. A critical reexamination of experimental data supports our findings, shedding doubts on the ferroelectricity of these systems. More generally, our modeling allows the rationalization of general features of the ferroelectric transition in charge transfer crystals and suggests design principles for materials optimization.

Introduction: Forkhead box E1 (FOXE1) is a transcription factor with a crucial role in thyroid morphogenesis and differentiation. Promoter hypermethylation downregulates FOXE1 expression in different tumor types; nevertheless, its expression and relationship with methylation status in differentiated thyroid cancer (DTC) remain unclear. Methods: A total of 33 pairs of matched samples of PTC tumors and non-tumors were included. Tumor cell cultures were treated with either 5-Aza-2′-deoxycytidine demethylating agent or dimethyl sulfoxide (DMSO). A real-time polymerase chain reaction (RT-PCR) and Western blotting were performed to assess FOXE1 expression. The methylation status was quantified using bisulfite sequencing. A luciferase gene assay was used to determine CpG-island functionality. Gene expression and promoter methylation of FOXE1 and FOXE1-regulated genes were also analyzed with data from The Cancer Genome Atlas (TCGA) thyroid samples. Results: After demethylating treatment, increased FOXE1 mRNA was observed concomitantly with reduced promoter methylation of CpGisland2. A negative correlation between mRNA downregulation and an increased methylation level of CpGisland2 was observed in tumors. Diminished protein expression was also detected in some DTC cell lines and in some tumor samples, suggesting the involvement of post-transcriptional regulatory mechanisms. CPGisland2 was proved to be an enhancer. TCGA data analysis showed low FOXE1 mRNA expression in tumors with a negative correlation with methylation status and a positive correlation with the expression of most of its target genes. Reduced FOXE1 expression, accompanied by a high methylation level, was associated with PTC aggressiveness (tall cell variant, advanced extra thyroid extension, T4 American Joint Committee on Cancer (AJCC) classification), age at diagnosis (over 45 years old), and presence of a BRAFV600E mutation. Conclusion: FOXE1 mRNA was downregulated in DTC compared with non-tumors, followed by high CpGisland methylation. A coupling of low mRNA expression and high methylation status was related to characteristics of aggressiveness in DTC tumors. [ABSTRACT FROM AUTHOR]

The Epstein-Barr viwrus (EBV) is a common herpesvirus that affects more than 90% of people worldwide. Even while EBV infections are frequently asymptomatic, they can cause autoimmune diseases and a number of cancers, especially in those with impaired immune systems. The intricate relationships between EBV and other coinfecting pathogens, including as human immunodeficiency virus (HIV), human papilloma virus (HPV), cytomegalovirus (CMV), and Plasmodium species, are examined in this study. We investigated the fundamental processes of these coinfections, their effects on the course of the disease, and their practical ramifications. The study reviewed how co-infections with EBV might modify immune responses, promote oncogenesis, and make treatment plans more challenging. In this review, we also discussed current therapeutic strategies, such as targeted molecular interventions, EBV vaccines, and adoptive T-cell therapy. The review underscores the need for more research to provide more focused and effective therapies that address the mutually reinforcing effects of numerous infections in disorders linked with EBV. [ABSTRACT FROM AUTHOR]

Electron beam melting is a powder bed fusion process capable of manufacturing parts from a variety of high-temperature alloys. Given that the process relies on feedstock recycling for process economics, understanding process-part quality relationships is critical. This work investigates process-part quality relationships in terms of the internal and external defects and component microstructure relative to a feedstock subjected to 33 build cycles without replacement. To accomplish this, a volume of fluid mesoscale model consisting of three different powder distributions were considered: (1) Monomodal; (2) As-measured; and (3) Irregular. Particle morphology was characterized using shape factors examined via optical microscopy. To approximate the particle shapes in three-dimensions, a method is presented that utilizes a binarized domain to define low frequency, macroscale particle "base" shapes implicitly and is thus not restricted to starlike particles. The discrete element method was also used to investigate velocity distributions and packing densities of the as-measured and irregular particles with respect to deviations in the nominal layer thickness of 50 μm. In general, beam power and scan speed were found to have an appreciable effect on microstructure formation and surface roughness. Finally, correlations were found between specific classifications of irregular particles and lack of fusion defect formation. [ABSTRACT FROM AUTHOR]

Molecular doping is essential to improve the electrical conductivity of organic semiconductors for high-performance organic electronic devices. However, the doping efficiency is influenced by several factors, such as the energy levels, energetic fluctuations, dielectric properties, and molecular packing structures of the doped films, and the underlying mechanisms for high-efficiency doping are still unclear. Here, through multi-level theoretical simulations on a series of fullerene derivatives, we identify that the energetic fluctuations can play a decisive role in activating charge separation for molecular doping. In particular, the doping efficiency appears to be exponentially increased with the fluctuation of charge polarization energies. Therefore, although the charge mobility is somewhat decreased, the experimental electrical conductivity is improved with the increased energetic fluctuation. Moreover, it has been found that polarization energy fluctuation can be effectively enhanced by simply introducing side chains with greater flexibility into organic semiconductors. This article paves the way towards high-efficiency molecular doping of organic semiconductors. [ABSTRACT FROM AUTHOR]

Standing surface acoustic waves (sSAW) emerged as a flexible tool for precise manipulation of spherical and non-spherical objects in Lab-on-a-Chip devices. While the manipulation of suspended particles and cells in acoustofluidic devices is mostly dominated by acoustic forces due to acoustic scattering and the acoustically induced fluid flow, surface acoustic waves are inherently linked to an inhomogeneous electric field. The superimposed effects of dielectrophoretic forces and torques on polarizable particles are less explored in microfluidics using sSAW. In this study, a thorough analysis of the physical interplay of acoustophoresis and dielectrophoresis aims to bridge this gap. In comprehensive experiments, the dielectrophoretic impact on the behavior of spherical and non-spherical particles is distinguished by screening the electric field of the sSAW inside the micro channel locally. As a result, particles are forced into trapping locations across the entire channel height. However, the height position close to the bottom differs between the screened and non-screened region. Regardless of the shape of the particles used in this study, particles are forced towards the bottom at the region with screening, while being levitated at regions without screening. This indicates clearly the influence of the electric field in close vicinity to the substrate surface. Furthermore, the unintuitive preferred orientation of prolate spheroids perpendicular to the pressure nodes of the sSAW recently reported, is confirmed in both region regardless of the presence of the electric field. Based on a three-dimensional numerical model, this orientation results not only due to the acoustic torque but is also caused by the dielectrophoretic torque, which complement each other. The experimental and numerical findings are in excellent agreement and provide deep insights into the underlying physical mechanisms responsible for patterning and orientation of the particles. [ABSTRACT FROM AUTHOR]

The powder spreading process is a fundamental element within the laser powder bed fusion (PBF-LP) framework given its pivotal role in configuring the powder bed. This configuration significantly influences subsequent processing steps and ultimately determines the quality of the final manufactured part. This research paper presents a comprehensive analysis of the impacts of varying spreading speeds, which are enabled by different roller configurations, on powder distribution in PBF-LP. By utilizing extensive Discrete Element Method (DEM) modelling, we systematically examine how spreading speed affects vital parameters within the spreading process, including packing density, mass fraction, and actual layer thickness. Our exploration of various roller configurations has revealed that increasing spreading speed generally decreases packing density and layer thickness for non-rotating, counter-rotating, and forward-rotating rollers with low clockwise rotational speeds (sub-rolling) due to powder dragging. However, a forward-rotating roller with a high clockwise rotational speed (super-rolling) balances momentum transfer, enhancing packing density and layer thickness while increasing surface roughness. This configuration significantly improves the uniformity and density of the powder bed, providing a technique to accelerate the spreading process while maintaining and not reducing packing density. Furthermore, this configuration offers crucial insights into optimizing additive manufacturing processes by considering the complex relationships between spreading speed, roller configuration, and powder spreading quality. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Recent breast cancer research has focused on tumour microenvironment (TME). Tumour-associated macrophages (TAMs) are the key players in TME as they provide pro-tumorigenic milieu for tumour progression and metastasis. These macrophages are primarily regulated by colony-stimulating factor-1 (CSF-1) secreted by breast cancer cells. This study investigated the association of localization of TAMs infiltration within breast carcinoma and CSF-1 expression by cancer cells with the pathological prognostic parameters. MATERIALS AND METHODS: TAMs were assessed in 128 cases of invasive breast carcinoma by CD163 immunohistochemical expression. The median TAM density in both the tumour nest and tumour stroma was utilized to classify TAMs into categories of low and high infiltration. The cancer cells were immunostained with anti-CSF-1 antibody and the staining intensity was evaluated as low or high expression. RESULTS: High nest and stromal TAMs were associated with higher tumour grades (p=0.005 and p=0.0001, respectively) whereas only high stromal TAMs showed significant association with negative oestrogen and progesterone receptors status (p=0.001 and 0.001, respectively); and triple-negative subtype (p=0.002). High CSF-1 expression was significantly associated with high stromal TAMs (p=0.031). High CSF-1 expression was associated with tumour grade and positive HER2 status (p=0.008 and 0.007, respectively). CONCLUSION: TAMs in tumour nest and stroma showed varying degrees of association with the clinicopathological parameters. High CSF-1 expression was associated with unfavourable prognostic parameters. Therefore, the evaluation of TAMs and CSF-1 expressions could potentially serve as prognostic markers and cellular targets for novel treatment modality in invasive breast cancers. [ABSTRACT FROM AUTHOR]

Quasi-periodic orbit families in astrodynamics are usually studied from a global standpoint without much attention to the specific orbits which are computed. Instead, we focus on the computation of particular quasi-periodic orbits and develop tools to do so. These tools leverage the parametric structure of families of quasi-periodic orbits to treat orbits only as a set of orbit frequencies instead of states in phase space. We develop a retraction on the family of quasi-periodic orbits to precisely navigate through frequency space, allowing us to compute orbits with specific frequencies. The retraction allows for movements in arbitrary directions. To combat the effects of resonances which slice through frequency space we develop resonance avoidance methods which detect resonances during continuation procedures and change the step size accordingly. We also develop an augmented Newton’s method for root-finding and an augmented gradient descent method for unconstrained optimization over a family of quasi-periodic orbits. Lastly, we implement an augmented Lagrangian method to solve constrained optimization problems. We note that many of the tools developed here are applicable to a wider range of solutions defined implicitly by a system of equations, but focus on quasi-periodic orbits. [ABSTRACT FROM AUTHOR]

Stromal cells play a critical role in the tumor microenvironment of breast cancer (BC), as they are recruited by tumor cells and regulate the metastatic spread. Though high expression of α-parvin, a member of the parvin family of actin-binding proteins, is reported to be associated with a poor prognosis and metastasis in several cancers, its role in carcinogenesis has not been thoroughly explored. Therefore, we aimed to examine the expression of α-parvin in BC patients by compartmentalizing and quantifying tissues to determine whether α-parvin can be a potential therapeutic target. We performed immunohistochemical (IHC) staining of α-parvin in BC tissues, and the IHC scores were calculated in the overall tissue, stroma, and epithelium using image analysis software. The expression of α-parvin was significantly higher in BC tissues (p = 0.0002) and BC stroma (p < 0.0001) than in normal tissues. Furthermore, all α-parvin scores were significantly positively correlated with the proliferation marker Ki67. The overall and stroma scores are associated with the tumor, (lymph) node, and metastasis (TNM) classification, stage, and grade. These results suggest that high expression of α-parvin in stroma is associated with BCs and might be a new predictive marker for diagnosing BC. [ABSTRACT FROM AUTHOR]

The substitution of heteroatoms and the functionalisation of molecules are established strategies in chemical synthesis. They target the precise tuning of the electronic properties of hydrocarbon molecules to improve their performance in various applications and increase their versatility. Modifications to the molecular structure often lead to simultaneous changes in the morphology such as different crystal structures. These changes can have a stronger and unpredictable impact on the targeted property. The complex relationships between substitution/functionalization in chemical synthesis and the resulting modifications of properties in thin films or crystals are difficult to predict and remain elusive. Here we address these effects for charge carrier transport in organic crystals by combining simulations of carrier mobilities with crystal structure prediction based on density functional theory and density functional tight binding theory. This enables the prediction of carrier mobilities based solely on the molecular structure and allows for the investigation of chemical modifications prior to synthesis and characterisation. Studying nine specific molecules with tetracene and rubrene as reference compounds along with their combined modifications of the molecular cores and additional functionalisations, we unveil systematic trends for the carrier mobilities of their polymorphs. The positive effect of phenyl groups that is responsible for the marked differences between tetracene and rubrene can be transferred to other small molecules such as NDT and NBT leading to a mobility increase by large factors of about five. [ABSTRACT FROM AUTHOR]

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The development of luminescent organic radicals has resulted in materials with excellent optical properties for near-infrared emission. Applications of light generation in this range span from bioimaging to surveillance. Although the unpaired electron arrangements of radicals enable efficient radiative transitions within the doublet-spin manifold in organic light-emitting diodes, their performance is limited by non-radiative pathways introduced in electroluminescence. Here we present a host–guest design for organic light-emitting diodes that exploits energy transfer with up to 9.6% external quantum efficiency for 800 nm emission. The tris(2,4,6-trichlorophenyl)methyl-triphenyl-amine radical guest is energy-matched to the triplet state in a charge-transporting anthracene-derivative host. We show from optical spectroscopy and quantum-chemical modelling that reversible host–guest triplet–doublet energy transfer allows efficient harvesting of host triplet excitons. Exploiting the energy transfer between the host triplet states and spin doublet exciton states of a radical organic emitter enables near-infrared organic light-emitting diodes with an external quantum efficiency up to 9.6% at an emission wavelength of 800 nm. [ABSTRACT FROM AUTHOR]

Conjugated polymers (CPs) are widely used as conductive materials in various applications, with their conductive properties adjustable through chemical doping. While doping enhances the thermoelectric properties of CPs due to improved main-chain transport, overdoping can distort the polymer structure, increasing energy disorder and impeding intrinsic electrical transport. This study explored how different dopants affect the structural integrity and electrical transport properties of CPs. We found that dopants vary in their impact on CP structure, consequently altering their electrical transport capabilities. Specifically, ferric chloride (FeCl3)-doped indacenodithiophene-co-benzothiadiazole (IDTBT) shows superior electrical transport properties to triethyloxonium hexachloroantimonate (OA)-doped IDTBT due to enhanced backbone planarity and rigidity, which facilitate carrier transport and lower energetic disorder. These results highlight the critical role of dopant selection in optimizing CPs for advanced applications, suggesting that strategic dopant choices can significantly refine the charge transport characteristics of CPs, paving the way for their industrialization. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) is not necessarily a new process but an advanced method for manufacturing complex three-dimensional (3D) parts. Among the several advantages of AM are the affordable cost, capability of building objects with complex structures for small-batch production, and raw material versatility. There are several sub-categories of AM, among which is fused filament fabrication (FFF), also commonly known as fused deposition modeling (FDM). FFF has been one of the most widely used additive manufacturing techniques due to its cost-efficiency, simplicity, and widespread availability. The FFF process is mainly used to create 3D parts made of thermoplastic polymers, and complex physical phenomena such as melt flow, heat transfer, solidification, crystallization, etc. are involved in the FFF process. Different techniques have been developed and employed to analyze these phenomena, including experimental, analytical, numerical, and finite element analysis (FEA). This study specifically aims to provide a comprehensive review of the developed numerical models and simulation tools used to analyze melt flow behavior, heat transfer, crystallization and solidification kinetics, structural analysis, and the material characterization of polymeric components in the FFF process. The strengths and weaknesses of these numerical models are discussed, simplifications and assumptions are highlighted, and an outlook on future work in the numerical modeling and FE simulation of FFF is provided. [ABSTRACT FROM AUTHOR]

Static dielectric tensors and charge carrier polarization energies of a wide set of organic molecules of interest for organic electronics application are calculated with two different approaches: intramolecular charge redistribution and induced dipoles (microlectrostatics). Our results show that, while charge redistribution is better suited for calculating the collective response to an external field, both methods reliably describe the effect of a localized charge carrier in the crystal. Advantages and limitations inherent to the different methods are discussed, also in relation to previous theoretical studies. The agreement with available experimental data confers to our results a predictive character where measurements are missing.

Improving the performance of organic photovoltaic cells requires the individuation of the specific factors limiting their efficiency, by rationalizing the relationship between the chemical nature of the materials, their morphology, and the electronic processes taking place at their interface. In this contribution, we present recent theoretical advances regarding the determination of the energetics and dynamics of charge carriers at organic-organic interfaces, highlighting the role of structural and electrostatic disorder in the separation of electron-hole pairs. The influence of interfacial electrostatic interactions on charge carrier energetics is first illustrated in model aggregates. Then, we review some of our recent theoretical studies in which we combined molecular dynamics, quantum-chemical and classical micro-electrostatic methods to evaluate the energy landscape explored by the mobile charges in the vicinity of donor-acceptor interfaces with realistic morphologies. Finally, we describe the theoretical challenges that still need to be overcome in order to gain a complete overview of the charge separation processes at the molecular level.

Neutrophils are the most abundant cell type in the immune system and play an important role in the innate immune response. Using a diverse range of mouse models with either defective dendritic cell (DC) development or conditional DC depletion, we provide in vivo evidence indicating that conventional DCs play an important role in the regulation of neutrophil homeostasis. Flk2, Flt3L, and Batf3 knockout mice, which have defects in DC development, have increased numbers of liver neutrophils in the steady state. Conversely, neutrophil frequency is reduced in DC-specific PTEN knockout mice, which have an expansion of CD8(+) and CD103(+) DCs. In chimeric CD11c-DTR mice, conventional DC depletion results in a systemic increase of neutrophils in peripheral organs in the absence of histological inflammation or an increase in proinflammatory cytokines. This effect is also present in splenectomized chimeric CD11c-DTR mice and is absent in chimeric mice with 50% normal bone marrow. In chimeric CD11c-DTR mice, diphtheria toxin treatment results in enhanced neutrophil trafficking from the bone marrow into circulation and increased neutrophil recruitment. Moreover, there is an increased expression of chemokines/cytokines involved in neutrophil homeostasis and reduced neutrophil apoptosis. These data underscore the role of the DC pool in regulating the neutrophil compartment in nonlymphoid organs.

The semiconducting and self-assembling properties of columnar discotic liquid crystals have stimulated intense research toward their application in organic solar cells, although with a rather disappointing outcome to date in terms of efficiencies. These failures call for a rational strategy to choose those molecular design features (e.g., lattice parameter, length and nature of peripheral chains) that could optimize solar cell performance. With this purpose, in this work we address for the first time the construction of a realistic planar heterojunction between a columnar donor and acceptor as well as a quantitative measurement of charge separation and recombination rates using state of the art computational techniques. In particular, choosing as a case study the interface between a perylene donor and a benzoperylene diimide acceptor, we attempt to answer the largely overlooked question of whether having well-matching donor and acceptor columns at the interface is really beneficial for optimal charge separation. Surprisingly, it turns out that achieving a system with contiguous columns is detrimental to the solar cell efficiency and that engineering the mismatch is the key to optimal performance.

The molecular organization of functional organic materials is one of the research areas where the combination of theoretical modeling and experimental determinations is most fruitful. Here we present a brief summary of the simulation approaches used to investigate the inner structure of organic materials with semiconducting behavior, paying special attention to applications in organic photovoltaics and clarifying the often obscure jargon hindering the access of newcomers to the literature of the field. Special attention is paid to the choice of the computational "engine" (Monte Carlo or Molecular Dynamics) used to generate equilibrium configurations of the molecular system under investigation and, more importantly, to the choice of the chemical details in describing the molecular interactions. Recent literature dealing with the simulation of organic semiconductors is critically reviewed in order of increasing complexity of the system studied, from low molecular weight molecules to semiflexible polymers, including the challenging problem of determining the morphology of heterojunctions between two different materials.

We demonstrate the possibility to achieve 3D particle focusing in a straight microchannel with a square cross-section by exploiting purely viscoelastic effects. Experiments are carried out by considering an elastic, constant-viscosity aqueous solution of PVP (polyvinylpyrrolidone) as the suspending liquid. Several flow rates and two channel dimensions (with a fixed particle size to channel dimension ratio) are investigated. A novel technique combining particle tracking measurements and numerical simulations is used to reconstruct the position of the flowing particles over the channel cross-section. The results show that, for all the investigated experimental conditions, particles migrate towards the channel centerline. Flow-focusing is enhanced by higher flow rates. The measured particle fractions can be rescaled according to a single dimensionless parameter, as already reported in the literature for the case of cylindrical channels. The so-obtained master curve can be used as a guide to predict the required focusing length. The effect of the entrance on the focusing channel length is also addressed. Finally, analogies and discrepancies with similar previous works are discussed.

The patient is a 56-year-old man with a long history of chronic hepatitis B, who developed multiple hepatocellular carcinomas in the right lobe with invasion of the right anterior portal vein. There was no evidence of tumor involvement in the left lobe or in extrahepatic organs. Given that the patient had advanced hepatocellular carcinoma associated with gross vascular invasion, a two-step liver resection procedure was performed with right portal vein ligation during the first operation and a subsequent right lobectomy of the liver. The stage I portal vein ligation induced a rapid growth of the left and caudate lobes of the liver with a volume increase from 201 to 405.2 mL in 9 days associated with a slight shrinkage of the tumor nodules. The subsequent right lobectomy was successfully done with a complete removal of tumor nodules and a well-compensated liver function. Postoperatively the patient was complicated with Staphylococcus aureus peritonitis, which was controlled eventually. Biopsy of the left lobe of liver revealed severe small- and medium- droplet steatosis, in addition to regenerative changes. In summary, right portal vein ligation with in situ splitting of the liver allows the surgeon to proceed with hepatic resection in cases where portal vein embolization is technically not possible. The increased risk of morbidity and mortality certainly must be weighed when contemplating this approach and is discussed in this report., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Particles suspended in non-Newtonian liquids flowing in channels may migrate transversally to the main flow direction as a result of normal stress gradients. Viscoelasticity-induced migration has proven to be an efficient mechanism to promote 3D flow-focusing in cylindrical microchannels, avoiding the need for complex and expensive apparati. In this work, we demonstrate the existence of a single dimensionless number (Θ) that governs the migration dynamics of particles in viscoelastic liquids flowing in micropipes at low Deborah numbers (Deborah number is the ratio of fluid and flow characteristic times). The definition of Θ in terms of the relevant fluid, flow and geometrical quantities is obtained by generalizing the particle migration velocity expression given in previous asymptotic analytical theories through numerical simulations. An extensive experimental investigation quantitatively confirms the novel predictions: the experimental particle distributions along the channel axial direction collapse on a single curve when rescaled in terms of the proposed dimensionless number. The results reported in this work give a simple and general way to define the flow-focusing conditions promoted by viscoelastic effects.

Pancreatic neuroendocrine tumors of the main pancreatic duct are rare and usually small due to symptoms of pancreatic duct obstruction. We present a case of a large (3 cm), well-differentiated (G1) lipid-rich polypoid neuroendocrine tumor of the pancreas completely occluding the main pancreatic duct with non-neoplastic-entrapped ductules and CK19 positivity. Clinical, radiological, gross, microscopic, immunohistochemical, and ultrastructural findings are discussed. The literature pertaining to the unique features of this case is reviewed including clinical and pathologic pitfalls and the possible etiologic and prognostic significance of these findings.

In recent years, microneedle (MN) patches have emerged as an alternative technology for transdermal delivery of various drugs, therapeutics proteins, and vaccines. Therefore, there is an urgent need to understand the status of MN-based therapeutics. The article aims to illustrate the current status of microneedle array technology for therapeutic delivery through a comprehensive review. However, the PubMed search was performed to understand the MN's therapeutics delivery status. At the same time, the search shows the number no of publications on MN is increasing (63). The search was performed with the keywords "Coated microneedle," "Hollow microneedle," "Dissolvable microneedle," and "Hydrogel microneedle," which also shows increasing trend. Similarly, the article highlighted the application of different microneedle arrays for treating different diseases. The article also illustrated the current status of different phases of MN-based therapeutics clinical trials. It discusses the delivery of different therapeutic molecules, such as drug molecule delivery, using microneedle array technology. The approach mainly discusses the delivery of different therapeutic molecules. The leading pharmaceutical companies that produce the microneedle array for therapeutic purposes have also been discussed. Finally, we discussed the limitations and future prospects of this technology. [ABSTRACT FROM AUTHOR]

Anaerobic membrane bioreactors (AnMBRs) have emerged as an effective technology for treating domestic and industrial wastewater. However, AnMBRs typically exhibit low membrane fluxes (<10 L/m2.h), which limits their wide application. Despite the use of various techniques to control membrane fouling, the relationships among these techniques and the challenges associated with their application remain unclear. Current literature categorizes membrane fouling control approaches into four classes, namely a reduction in the concentration of soluble microbial products (SMP), an increase in shear, an increase in particle size, and membrane optimization. Biological techniques are effective in reducing the concentration of SMP but limit the flexibility of reactor operation. The remaining three methods are non-biological techniques. Shear-induced lift force, permeation drag force, and the xDLVO theory on microparticles can be used to elucidate the mechanisms of these non-biological techniques, except for dynamic membranes. This indicates that other proposed additional forces may be disregarded. Non-biological techniques are associated with high energy costs and membrane damage. Hydrophilic membranes are effective but super-hydrophilic membranes have not been used in AnMBRs. Different materials rather than the membrane should be applied to create an electronic field for membrane fouling control. The application of dynamic membrane should not result in biofouling of a downstream water treatment process. Among current techniques, dosing flocculant is the most promising method for controlling membrane fouling, but developing an auto-flocculant dosing strategy is vital. Overall, this article provides an overview of current membrane fouling strategies and reveals their inherent relationships and challenges for their applications. [ABSTRACT FROM AUTHOR]

We perform 3D numerical simulations, heuristic modeling and microfluidic experiments to demonstrate, for the first time, the presence of a bistability scenario for transversal migration of particles suspended in a viscoelastic liquid flowing in a pipe. Our results show that particle migration, either at the centerline or at the wall, can be controlled by the rheological properties of the suspending liquid and by the relative dimensions of the particle and tube. Proper selection of these parameters can promote strict aligning of particles on a line, i.e., 3-D focusing. Simple design rules are given to rationally control particle focusing under flow in micropipes.

Essential state models are presented to discuss absorption spectra of two related donor-acceptor (DA) chromophores that show two solvatochromic bands in the near-infrared spectral region. The two-state model only accounts for the lowest energy band and results in a very small value of mu(0), the dipole moment associated with the D(+)A(-) state. The model is then extended to account for the active role of the bridge: the resulting three-state model satisfactorily reproduces the double solvatochromism, leading at the same time to a roughly doubled estimate of mu(0). This result, supported by a detailed analysis of an N-state model that explicitly accounts for bridge states, rationalizes the well-known discrepancy between the geometrical DA distance and the dipole length extracted from the analysis of optical spectra of DA chromophores as reflecting the active role of bridge states, not explicitly accounted for in essential state models.

Microfluidic separation of particles and cells is crucial to lab-on-a-chip applications in the fields of science, engineering, and industry. The continuous-flow separation methods can be classified as active or passive depending on whether the force involved in the process is externally imposed or internally induced. The majority of current separations have been realized using only one of the active or passive methods. Such a single-mode process is usually limited to one-parameter separation, which often becomes less effective or even ineffective when dealing with real samples because of their inherent heterogeneity. Integrating two or more separation methods of either type has been demonstrated to offer several advantages like improved specificity, resolution, and throughput. This article reviews the recent advances of such multimode particle and cell separations in microfluidic devices, including the serial-mode prefocused separation, serial-mode multistage separation, and parallel-mode force-tuned separation., (© 2023 The Authors. Electrophoresis published by Wiley-VCH GmbH.)

Fc-PTM is a valence tautomeric radical, where the ferrocene (Fc) group, a good electron donor, is linked by an ethylenic spacer to a perchlorotriphenylmethyl radical (PTM(*)), a good electron acceptor. In solution this compound exists mainly in the neutral Fc-PTM(*) form which can be photoexcited through an intramolecular electron transfer to the zwitterionic Fc(+*)-PTM(-) form. By contrast, in crystals of Fc-PTM at room temperature both the neutral and the zwitterionic forms coexist, pointing to a true bistability phenomenon. We rationalize these findings accounting for the role of intermolecular electrostatic interactions in Fc-PTM crystals. In fact the energy of the zwitterionic Fc(+*)-PTM(-) form is lowered in the crystal by attractive electrostatic intermolecular interactions and the cooperative nature of these interactions explains the observed coexistence of neutral Fc-PTM(*) and zwitterionic Fc(+*)-PTM(-) species. The temperature evolution of Mossbauer spectra of Fc-PTM is quantitatively reproduced adopting a bottom-up modeling strategy that combines a molecular model, derived from optical spectra of Fc-PTM in solution, with a model for intermolecular electrostatic interactions, supported by quantum-chemical calculations. Fc-PTM then offers the first experimental demonstration of bistability induced by electrostatic interactions in crystals of valence tautomeric donor-acceptor molecules.

To fully exploit the promise of molecular materials for NLO applications, inter- and supramolecular interactions must be accounted for. We review our recent work on electrostatic interchromophore interactions in multichromophores for NLO applications. The discussion is based on a bottom-up modeling strategy: each chromophore is described in terms of an essential state model, validated and parameterized against spectroscopic data for solvated chromophores. The relevant information is then used to build a model for clusters of chromophores interacting through electrostatic forces. Exact NLO responses and spectra calculated within this model fully account for collective and cooperative interchromophore interactions, which can either amplify or suppress NLO responses; supramolecular engineering of multichromophores is a powerful tool for the design of NLO materials. Moreover, new features emerge in multichromophores with no counterpart at the single-chromophore level, offering new exciting opportunities for applications.

Diffuse x-ray data for mixed-stack organic charge-transfer crystals approaching the neutral-ionic phase transition can be quantitatively explained as due to the softening of the optical phonon branch. The interpretation is fully consistent with vibrational spectra, and underlines the importance of electron-phonon coupling in low-dimensional systems with delocalized electrons.

Directed evolution is a powerful technique for creating biomolecules such as proteins and nucleic acids with tailor-made properties for therapeutic and industrial applications by mimicking the natural evolution processes in the laboratory. Droplet microfluidics improved classical directed evolution by enabling time-consuming and laborious steps in this iterative process to be performed within monodispersed droplets in a highly controlled and automated manner. Droplet microfluidic chips can generate, manipulate, and sort individual droplets at kilohertz rates in a user-defined microchannel geometry, allowing new strategies for high-throughput screening and evolution of biomolecules. In this review, we discuss directed evolution studies in which droplet-based microfluidic systems were used to screen and improve the functional properties of biomolecules. We provide a systematic overview of basic on-chip fluidic operations, including reagent mixing by merging continuous fluid streams and droplet pairs, reagent addition by picoinjection, droplet generation, droplet incubation in delay lines, chambers and hydrodynamic traps, and droplet sorting techniques. Various microfluidic strategies for directed evolution using single and multiple emulsions and biomimetic materials (giant lipid vesicles, microgels, and microcapsules) are highlighted. Completely cell-free microfluidic-assisted in vitro compartmentalization methods that eliminate the need to clone DNA into cells after each round of mutagenesis are also presented. [ABSTRACT FROM AUTHOR]

Deploying a lens informed by humanitarian reason and governmentality this article interrogates the normative assumptions underlying resettlement for international protection in the Irish context. Drawing on findings from a qualitative study on the needs of children and parents admitted under the Irish Refugee Protection Programme, it highlights tensions and contradictions underemphasised in the existing literature, including those deriving from assumptions which inversely associate age with integrate-ability. Such assumptions place a heavy burden on the young, perceived to be the most adaptable. The danger pointed to in this article is that those deemed least adaptable - adults with limited prior education - might not be prioritised for supports due to negative assumptions about their prospects. Somewhat paradoxically, the 'most adaptable' – children resettled at primary-school age or younger – might also miss out on supports as they are deemed likely to succeed in any case. [ABSTRACT FROM AUTHOR]

Obesity is a major public health issue that is associated with metabolic diseases including diabetes mellitus type 2 and metabolic syndrome. This pathology leads to detrimental cardiovascular health and secondary effects, such as lipotoxicity, inflammation, and oxidative stress. Recently, extracellular vesicles (EVs) have been highlighted as novel players participating in human physiology and pathophysiology. In obesity, adipose tissue is related to the active shedding of adipocyte-derived extracellular vesicles (AdEVs). The current review explores and highlights the role of AdEVs and their cargo in obesity and metabolic syndrome. AdEVs are proposed to play an important role in obesity and its comorbidities. AdEVs are biological nanoparticles mainly shed by visceral and subcutaneous adipose tissue, acting in physiological and pathophysiological conditions, and also carrying different cargo biomolecules, such as RNA, microRNA (miRNA), proteins, and lipids, among others. RNA and miRNA have local and systemic effects affecting gene expression in target cell types via paracrine and endocrine actions. State of the art analyses identified some miRNAs, such as miR-222, miR-23b, miR-4429, miR-148b, and miR-4269, that could potentially affect cell pathways involved in obesity-related comorbidities, such as chronic inflammation and fibrosis. Similarly, AdEVs-proteins (RBP4, perilipin-A, FABP, mimecan, TGFBI) and AdEVs-lipids (sphingolipids) have been linked to the obesity pathophysiology. The current knowledge about AdEVs along with further research would support and reveal novel pathways, potential biomarkers, and therapeutic options in obesity. [ABSTRACT FROM AUTHOR]