Diameter Standard Deviation Research Articles

Characterisation of Three Ovine KRTAP13 Family Genes and Their Association with Wool Traits in Chinese Tan Sheep.

Understanding the genetic basis of wool traits is crucial for improving wool production. In this study, we investigated the ovine KAP13 gene family, which in humans contains multiple members, while only one member has been identified to date in sheep. Three ovine KRTAP13 genes, likely representing KRTAP13-1, KRTAP13-2, and KRTAP13-4, were identified through sequence analysis and phylogenetic comparisons. These genes are positioned on chromosome 1, between KRTAP15-1 and KRTAP27-1, in a pattern that is like the arrangement in humans but not identical. Analyses revealed multiple sequence variants of each gene in 356 sheep from a variety of wool, meat, and dual-purpose breeds. The effect of these genes on four fibre traits: mean fibre curvature (MFC), mean fibre diameter (MFD), coefficient of variation of fibre diameter (CVFD), and fibre diameter standard deviation (FDSD), was assessed in 240 lambs of the Chinese Tan sheep breed. An allele of KRTAP13-2 was revealed to be associated with a decrease in FDSD and CVFD in heterotypic fibres. No associations were found between KRTAP13-4 variation and wool traits, and an association analysis for KRTAP13-1 was not conducted because no variation was found in this gene in the Chinese Tan sheep studied. These findings suggest a potential role for KRTAP13-2 in regulating wool traits, particularly fibre diameter uniformity in larger heterotypic hair fibres, and suggest its potential use as a marker for improving wool traits.

Effects of KRTAP20-1 Gene Variation on Wool Traits in Chinese Tan Sheep.

Chinese Tan sheep lambs are recognised for having tight 'spring-like' curly wool when young, but this phenotype disappears with age. This wool consists of shorter, fine wool fibres (which are usually unmedullated) and heterotypic hair fibres (which are frequently medullated), which are referred to as 'halo hair'. Both the wool and hair fibres consist of α-keratin proteins embedded in a keratin-associated protein (KAP) matrix. Of these KAPs, the KAP20-1 gene (designated KRTAP20-1) and its effect on four fibre traits (mean fibre curvature, mean fibre diameter, fibre diameter standard deviation, and coefficient of variation of fibre diameter) of Tan lambs was studied. Seven previously identified KRTAP20-1 variants (A, B, D, E, F, G, and H) of KRTAP20-1 were revealed, but the previously identified variant C was not present. Of the seven variants detected, only two (A and G) were common and present at frequencies greater than 5%, and the effect of these on the fibre traits of the finer wool fibres was assessed. It was found that variant G was associated with an increased mean fibre curvature in these wool fibres. This suggests that KRTAP20-1 might possibly be expressed differentially in the two fibre types, which may be of future value in breeding.

Fabrication of electrostatic-induction-assisted solution blowing spinning nanofibers and its mechanism

Commonly used nanofiber fabrication technologies have many shortcomings: the yield of electrospinning is low, solution blowing spinning (SBS) and its improved technologies have problems with large fiber diameter, non-uniform nanofiber diameter and poor receiving aggregation of nanofibers on receiver. A nanofiber fabrication technology called electrostatic-induction-assisted solution blowing spinning (ESBS), which overcomes these disadvantages, was developed in this paper. This technology utilizes the joint action of electrostatic force and airflow stretching force to stretch the jet to fabricate nanofibers. The grounding of the blunt needle realizes the directional migration and dynamic circulation of charges in the ESBS microscopic system. Compared with traditional SBS, the average diameter and diameter standard deviation of ESBS nanofibers can be reduced by 44 % and 80.8 %, respectively, and the fiber cover rate can be increased by 329.7 %. In contrast to the cylindrical-electrode-assisted solution blowing spinning, the mean diameter and diameter standard deviation of ESBS nanofibers can be reduced by 34.6 % and 68.1 %, respectively, and the fiber cover rate can be increased by 305 %. The microcosmic fabrication mechanism of ESBS nanofibers—“the theory of separation and directional transfer of charges” was proposed and verified. ESBS nanofibers with single-needle injection speed up to 200 μl/min (far exceeding the 4–10 μl/min injection speed of conventional electrospinning) were successfully fabricated to prove that this technology has great industrial potential. ESBS nanofibers with small and uniform diameter, high yield, and good receiving aggregation of fibers on receiver have bright application prospects in many fields.

Large-scale fabrication of nanofibers by tiny-needle-spaced electrostatic-induction-assisted solution blowing spinning

In this paper, a technology and device for large-scale fabrication of nanofibers called tiny-needle-spaced electrostatic-induction-assisted solution blowing spinning (TESBS) was developed. The airflow stretching force is used as the initial driving force for jet formation in TESBS, which avoids the electric field interference existing in the jet formation stage of multi-needle electrospinning(MES). The addition of an induced electric field in TESBS solves the problem of mutual merging of jets in multi-needle solution blowing spinning (MSBS). The needle spacing of TESBS can be as small as 1 mm, which is much smaller than MES (100 mm) and MSBS (3 mm). The substantial reduction in needle spacing can increase the arrangement density of blunt needles, thereby increasing the output of nanofibers. Compared with MSBS, the average diameter and diameter standard deviation of TESBS nanofibers can be reduced by 52.6% and 78.7%, respectively. Compared with MES, the uniformity of the TESBS nanofiber web has been significantly improved. The formula for the critical needle spacing to ensure that the TESBS jets do not merge with each other was derived. The output of 15-needle TESBS can reach as high as 3 ml/min. The average diameter of TESBS nanofibers decreases with the decrease in injection speed or the increase in voltage. The distance between the needle and the receiver has little effect on the average fiber diameter. TESBS nanofibers with good quality and high yield have broad and bright application prospects in many fields.

Assessment of Critical Quality Attributes of Budesonide and Formoterol Fumarate Dihydrate in Dry Powder Inhalers Marketed in Pakistan

Dry powder inhalers (DPIs) have been well established and recognized for the delivery to the lungs. It provides better drug stability, less irritable, easy to use with deep penetration of drugs in the lungs. Budesonide (BDS) and formoterol fumarate dihydrate (FFD) indicated in pulmonary diseases. The main aim of the study is to evaluate BDS, FFD and their marketed DPIs product in Pakistan were compare in quality and performance with the reference product. The particle size distribution and aerodynamic characterization were analyzed by laser diffraction and multi stage liquid impinger, respectively. The particle density and delivered dose uniformity were also determined. HPLC was also used for the qualitative and quantitative estimation of BDS and FFD along with its marketed products. Laser diffraction particle size analyzer revealed Dv50 53.27 to 56.34 and#181;m having surface area 1815 to 2304 cm3/g. The percentages of emitted dose (%ED) and fine particle fraction (%FPF) was found 98.19 to 99.23% and 31.57 to 34.87%, respectively. The mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) were calculated 2.62 to 2.89 and#181;m and 1.99 to 2.54, correspondingly. The quantitative assay of BDS and FFD in all the commercial DPIs and reference product were well within the pharmacopeial limit i.e. 97.26 to 101.36%. The average of ten units results of delivered dose uniformity for BSD and FFD were also found in the range i.e. 97.97 to 103.19% and 98.48 to 104.41 %, respectively. The results of evaluation of parameters of DPIs like Dv50, %ED, %FPF, MMAD, GSD has shown compliance with the pharmacopeial standards. It is concluded that the all DPIs of BDS/FFD marketed in Pakistan has revealed conformance with the standard of pharmacopoeia and meet the requirements of drug regulatory authority of Pakistan.

Cell Performance Prediction of the Particle Structure of All-Solid-State Batteries By Numerical Simulation and Machine Learning

All-Solid-State Battery (ASSB) is expected to be commercialized for electric vehicle applications. However, the correlation between the electrode structure and the cell performance is unknown, and no design theory has been established. Especially the effect of contact stress on solid-solid interface is important. And the ununiform reaction area cause the exsess current concentration. In our previous study, we developed various simulation model to understand the effect of heterogeneous structure and the effect of volume expansion on dynamic structure change during charging-discharging cycle from the viewpoint of durability. In this study, we developed new simulation model with stress calculation and electrochemical reaction, Moreover, the simulation results were used to create training dataset for machine learning. By using these approaches, we tried to develop new method to predict cell performance from composite electrode structure to cell performance.The stress estimation was performed using the discrete element method (DEM) [1]. The various material parameters are used such as, particle diameter (average and standard deviation), Young's modulus, Poisson's ratio and density. The distribution of the stresses on each particle was calculated from the DEM calculation results and confirmed to be approximately Gaussian.To simulate electrochemical reaction and mass transport in electrode layer, we used multi-network model (MNM)[6]. The schematic image of this model is shown in Fig.1, we used various network grid of active material network, solid electrolyte network and interface network. Basic equations of Li concentration, Li potential and electron potential were calculated in these networks. In this study, with DEM and MNM, we developed new simulation model shown in Fig.2.A convolutional neural network (CNN) [7] was used as the model for machine learning, and various structural parameters, including the DOD, cell potential, and stress on each particle calculated by DEM, were identified to create a dataset. 250 images were used for training, 150 of which were used for training, 50 for validation, and 50 for testing. The coefficient of determination (R²) of the standard deviation of DOD and potential is almost 0.7 in each condition, and the cell performance can be predicted by the machine learning model. The contact area of the electrochemical reaction interface, AM-SE, was calculated from the stress on the contact surface calculated by DEM and Hertzian contact theory [8]. Thus, we can express the relationship between interface mechanical stress on solid-solid and effective reaction, and this effect can be predicted with various structure of composite electrode layer by using machine learning. It was possible to predict the cell performance and effective contact area in the electrode layer of the all-solid-state battery.Acknowledgement:This research was carried out under the project (Grant Number JPMJMI21G4) supported by the JST-Mirai Program, Japan.

Incense smoke (IS) inhalation exposure system: Physicochemical characterization, IS particle deposition and clearance in human airway using MPPD model

Incense smoke (IS) is source of indoor air pollution and key risk for diverse human diseases. Less information is available regarding controlled IS rodent inhalation exposure system and IS particulate matter (PM) deposition in human airways. Study aimed to demonstrate stable ISPM physicochemical parameters of 10 incense products inside the customized whole body inhalation exposure chamber (without animal) connected to smoke generation unit via aerosol mixing device. IS analyzed for size segregated PM emission, ISPM in vitro aerodynamics (MMAD and GSD determination), fine and ultrafine particle's SEM, SEM-EDX and PAH analysis. Using real life exposure scenario by utilizing MMAD, GSD and PM concentration after Tier 1 exposure assessment as key input parameters, ISPM dosimetry in infant (3 months) and adult (21 years male and female) human airways was calculated using multiple-path particle dosimetry (MPPD 3.04) modeling. Mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) ranged between 0.55 and 2.10 μm and 1.22 to 1.77 (polydisperse) respectively. PM1.0 and PM0.1 showed multiple morphology and presence of heavy and trace elements. PAH like acenaphthylene, anthracene, fluorene, naphthalene and phenanthrene were detected (0.84–143.17 μg/g). MPPD results showed higher ISPM deposition in pulmonary region and lowest in trachea bronchial region. ISPM deposition in tissue was higher in lower, peripheral lung as compared to upper and central lung tissue. Whole body inhalation exposure system showed stable IS atmosphere (physicochemical parameters) indicating the device suitability in future inhalation studies. MPPD ISPM deposition fraction and clearance data showed deep lung penetrating and retention behavior with higher risk in infant followed by female and then male. These modeled particle deposition and clearance data may be useful in risk assessment analysis of IS.

Use of real-time monitors to evaluate the potential exposure of secondhand electronic cigarette particulate matter inside vehicles

Electronic cigarette (ECIG) use continues to be highly prevalent, especially among youth and young adults. Potential exposure from secondhand ECIG particulate matter (PM) places bystanders in danger of inhaling harmful substances, especially in confined spaces. This study was conducted to measure the potential exposure from secondhand ECIG PM exposure in vehicles, with participants completing a 30-min ECIG use session in their own vehicle with their preferred ECIG device. Sessions included a 5-min, 10-puff directed bout (30-s interpuff interval), followed by a 25-min ad libitum bout in which participants could take as many puffs as desired. Real-time PM1, PM2.5, and PM10 (the 50% efficiency mass cut-off of that passes through a size-selective inlet at 1 μm, 2.5 μm, and 10 μm aerodynamic diameters, respectively) measurements were captured during the sessions using portable PM monitors (MiniWRAS, pDR, SidePak, and GeoAir2 low-cost monitors). A total of 56 participants with valid measurements were included in the study, with a total of 13 unique ECIG device brands, including Vuse Alto, Box Air Bar, ElfBar, Esco Bar, Aegis Legend, Hyde Edge, JUUL, Kang Onee Stick, Kang Onee Stick Plus, Nord X, Nord 2, Nord 3, and Vaporesso. During the 5-min directed bout, the highest real-time PM2.5 mean concentrations were 175 μg/m3 for the MiniWRAS, 1050 μg/m3 for pDR and 3314 μg/m3 for SidePak. The filter measurements were not detectable in most experiments, except for two participants, with one taking 205 puffs and the other taking 285 puffs, approximately 10 times the mean (30) puffs of all participants. The evaluation of GeoAir2 with the MiniWRAS showed a wide range of Pearson correlation coefficient (r) values, ranging from −0.03 to 1.00, for the 13 ECIG brands. The mass median diameter (0.31 μm–3.42 μm) and geometric standard deviation (2.47–8.21) were different based on the participants for the same ECIG brand.

Study of Mass Transfer Enhancement of Electrolyte Flow Field by Rotating Cathode in Through-Mask Electrochemical Micromachining.

To solve the problem of the nonuniform distribution of temperature and electrolytic products in the electrolyte flow field during through-mask electrochemical micromachining, the use of a rotating cathode with surface structures is proposed. The rotation of the cathode increases the efficiency of heat and mass transfer by the electrolyte flow. Simulations are performed to analyze the influence of the type of surface structure, the number of surface structures, and the rotational speed of the cathode on the electrolyte flow field. The results show that the use of a rotating cathode with surface structures significantly improves the mass transfer efficiency of the electrolyte flow field in comparison with a conventional cathode structure, and, in particular, a grooved rotating cathode can increase the outlet flow velocity by about 23%. An experimental demonstration of micropit array processing shows that the use of a grooved rotating cathode increases the mass transfer efficiency by 34% and the processing efficiency by nearly 40% compared with a smooth-surfaced rotating cathode. The grooved rotating cathode also gives the highest machining accuracy. Using this cathode, a uniform micropit array with an average micropit diameter of 201.83 μm, a diameter standard deviation of 3.49 μm, and a depth standard deviation of 0.87 μm is processed.

Parameterization of polydisperse aerosol optical properties during hygroscopic growth

Aerosol water uptake and the related influence on its optical properties owing to the hygroscopic growth of polydisperse aerosols have a significant effect on air quality and climate. This study develops an analytical parameterization for a single hygroscopic optical parameter and the scattering enhancement factor for polydisperse aerosol sizes. Polydisperse lognormal size distributions for geometric mean diameters of 0.05–1 μm and geometric standard deviations of 1.3–2.5 are considered with real refractive indices between 1.35-1.6. The analytical expression obtained for the optical parameter is compared to Mie theory and reasonable agreements within the size range investigated in this study are observed. Further, our results show that the analytical expression could express polydispersed aerosol optical properties as a function of geometric mean diameter and geometric standard deviation of a lognormal distribution and the refractive index. The obtained analytical expression can be efficiently used for 3D models with a reduced computational burden.

Abstract 5183: Development of an aerosol-based immunotherapy for lung cancer

Abstract Lung cancer is one of the leading causes of cancer death and the second most cancer in the world. Compared to systematic administration, local delivery of therapeutic agents to the lung increases their accumulation in lung cancer cells and reduces the toxicity in other organs. We previously discovered an anti-PD-L1 peptide that can be potentially uses for lung cancer therapy. This project aims to develop an aerosolized formulation of the anti-PD-L1 peptide for the treatment of lung cancer. We hypothesize that the aerosolized peptide has higher accumulation in the lung compared to systematic formulations, leading to high therapeutic index with less side effects. We developed a spray freeze-drying procedure and optimized the formulation to prepare the peptide dry powders. The median mass aerodynamic diameter (MMAD) and geometric standard deviation (GSD) of the aerosols were determined by an 8-stage Andersen Cascade Impactor. The morphology of the aerosols was studied using a scanning electron microscope (SEM). The stability of the aerosols in lung fluid was evaluated. Blocking assay suggested that the aerosolized formulation maintains the blocking efficiency of the peptide. Intratracheal administration of the peptide dry powder shows a high accumulation of the peptide in the lung. Citation Format: Yongren Li, Zhen Zhao, John Fetse, Reaid Hasan, Umar-Farouk Mamani, Yuhan Guo, Kun Cheng. Development of an aerosol-based immunotherapy for lung cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5183.

Mean nearest-neighbor distance in random 2D binary mixtures

The two-dimensional, mean nearest-neighbor distances, in random sequential addition hard disc computer-generated patterns with mixtures of two circle diameters, have been studied. The mean nearest-neighbor distance at a given area fraction is a quadratic polynomial function of the circle diameter standard deviation. Deviations from the uniform case may be either positive or negative, with large deviations (10–25%) at large circle diameter standard deviations. Nearest-neighbor distance distributions for binary mixture patterns may be well fit by skewed normal distributions.

Post treatment and properties of PVA/SS composite nanofibers

Using deionized water as a solvent, the polyvinyl alcohol/silk sericin (PVA/SS) mixed solution was prepared, and the PVA/SS composite nanofiber membrane was spun by the electrostatic spinning method. The characteristics and properties of the PVA/SS composite nanofiber membrane untreated and treated with methanol and ethanol steam were analyzed by scanning electron microscope, infrared spectrum and X-ray diffraction. The results showed that the morphology of the PVA/SS composite nanofibers was fine in this experiment. The average diameter and standard deviation of diameter first increased, then decreased and at last increased with the increase of the SS content. The average diameter of nanofibers treated with methanol and ethanol steam was smaller than that without treatment. The infrared spectrum showed that the peak value of SS in the PVA/SS composite nanofibers treated with methanol steam and ethanol steam for 3 d changed. X-ray diffraction showed that the crystallization of the PVA/SS composite nanofiber membrane after being treated with methanol and ethanol vapor was changed. The results provide theoretical support for biomedical materials and tissue engineering scaffolds.

Study on mass concentration and morphology of SMAW fume particles with a new covered electrode using nano-CaTiO3 as an arc stabilizer

Advances in manufacturing emphasize on the development of sustainable and green manufacturing processes. Welding is a popular manufacturing process practiced worldwide. The paper presented here describes a new covered electrode for a shielded metal arc welding (SMAW) process wherein nano-sized calcium titanate (CaTiO3) powder was used as an arc stabilizer, replacing the conventional micro sized CaTiO3 in the flux. The effect of this flux modification on the mass concentration and morphology of welding fume particulates was systematically investigated. The mass concentration of coarse, fine and sub-micron sized fume particulates was measured by segregating the fumes in a four-stage personal cascade impactor. The particle mass distribution was estimated from the mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) of the fume particulates. The morphology of fumes at each impactor stage was analysed using scanning electron microscopy and its count median diameter (CMD) was determined. The results indicated as much as 48 % reduction in total fumes and 54 % reduction in the breathing zone concentration of fumes when the entire CaTiO3 in the electrode flux was substituted with nano-CaTiO3. Morphological analysis indicated that a large fraction of the fumes from the conventional electrode were polydispersed particles, while the new electrodes predominantly contained monodispersed particles which have a relatively faster rate of removal from the lungs. Overall, the present work indicated that introducing nano sized CaTiO3 as an arc stabilizer to the flux covering of SMAW electrode could not only reduce the hazardous fume emissions but also reduce its biological activity and toxicity, thus making the process more sustainable and environment friendly.

Optimization and Scale Up of Spray Dried CPZEN-45 Aerosol Powders for Inhaled Tuberculosis Treatment.

PurposeTuberculosis (TB) remains one of the most serious diseases caused by a single organism. Multiple (MDR) and extensively (XDR) drug resistant disease poses a threat to global health and requires new drugs and/or innovative approaches to treatment. A number of drugs have been proposed as inhaled therapy for TB, frequently prepared by spray drying. CPZEN-45 is a novel anti-tubercular drug that has poor oral bioavailability but has shown promise when administered via inhalation.MethodsExcipient-free CPZEN-45 HCl has been spray dried into a powder with physicochemical characteristics, aerodynamic particle size distribution, and delivered dose suitable for consideration as an inhaled product.ResultsThe mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) of the powder delivered using a RS01 inhaler were 2.62 ± 0.04 μm and 1.76 ± 0.09, respectively. Additionally, the powder was physically and chemically stable after storage at ambient conditions for >1.5 years with particle size similar to freshly manufactured product. Overages in spray dried powder were recycled the powder and resprayed into drug product likewise resulting in negligible change in quality thus allowing for further preclinical characterization as necessary. CPZEN-45 was scaled up using pilot-scale manufacturing equipment where the density of the powder was increased to facilitate larger delivered doses without affecting the aerodynamic performance properties.ConclusionThe spray dried powders were suitable for pharmacokinetics, efficacy and preclinical toxicology studies. The final method of manufacture may be used directly for CGMP particle manufacture to support IND and Phase I clinical trials and beyond.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11095-022-03393-w.

Inhalation Potential of Rifampicin-Loaded Novel Metal-Organic Frameworks for Improved Lung Delivery: Physicochemical Characterization, In Vitro Aerosolization and Antimycobacterial Studies.

Background: The aim of the current study was to examine the potential of a rifampicin-loaded metal-organic framework (RIF@ZIF-8) for management of tuberculosis. Materials and Methods: RIF@ZIF-8 was developed using a simple, economic, and environmentally friendly ultrasonication method. Furthermore, the developed metal-organic framework (MOF) formulations were subjected to physicochemical characterization analyses such as Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), powder X-ray diffractometry, thermogravimetric analysis, field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and UV spectroscopy. In addition, in vitro release, powder flow characterization, in vitro lung deposition, and efficacy studies against the Mycobacterium tuberculosis (MTB) H37Rv strain were performed. Results: Physicochemical characterization confirms its spherical shape and drug loading, whereas in vitro release analysis shows 80.5 ± 5.5% release of the drug from the loaded formulation within 48 hours. Furthermore, powder flow properties suggested that the nature of MOFs is free flowing. Additionally, in vitro lung deposition studies indicated an emission fraction of 88.02 ± 10.23% for the emitted dose and circa 21% fine particle fraction. The mass median aerodynamic diameter and geometric standard deviation were found to be 4.42 ± 0.07 μm and 1.55 ± 01 μm, respectively. The in vitro aerosol performance study demonstrated higher deposition at stages 3, 4, and 5 of the cascade impactors, which simulate deep lung delivery in terms of the trachea-primary bronchus and secondary and terminal bronchi of the human lung, respectively. Moreover, RIF@ZIF-8 exhibited improved antimycobacterial activity (0.0125 mg/mL) vis-à-vis an unformulated drug (0.025 mg/mL) against the MTB H37Rv strain, using the BACTEC 460TB system. Conclusions: Therefore, MOFs could be promising nanocarriers for targeting lungs and overcoming the hepatotoxicity associated with antituberculosis drugs requiring inhalation administration.

Airborne nanoparticle analysis mini-system using a parallel-type inertial impaction technique for real-time monitoring size distribution and effective density

To elucidate the relationship between exposure to airborne nanoparticles (NPs; < 300 nm particles) and adverse health effects, two of their characteristics — size distribution and effective density— should be measured in real-time as they are key parameters that determine the particle deposition patterns in human airways. However, current lab-grade and portable instruments that assess airborne NPs only measure their size distribution; in addition, they are bulky and expensive, limiting their application to the analysis of individual NP exposure. To overcome these limitations, in this paper, we introduce and successfully demonstrate an NP analyzer realized in a mini-fluidic system whose main components were realized on two printed circuit boards (PCBs) that were subsequently adjoined. Our sensor could analyze the effective density and lognormal size distribution (number concentration, median diameter, and geometric standard deviation) of NPs in real time. Moreover, since an innovative NP analysis algorithm based on a parallel-type microfluidic inertial impaction technique is integrated in a miniature system, our sensor was portable (16.0 × 9.9 × 7.85 cm3, 980 g) and cost-efficient. In performance tests using synthesized NPs and in real-world environmental application tests, the performance of our sensor was comparable to that of conventional NP analysis systems. These results indicate that our mini-system is excellently suited to be used in hand-held sensors or distributed sensor networks for personal NP exposure monitoring, and toxicological studies.

Pore size regulation of polyamide composite membrane via a sol-gel process confined within the selective layer

Membrane with pores of homogeneous size distribution is vital to high fraction efficiency of nanofiltration process. In this study, a novel approach of space-confined sol-gel was put forward to regulate the size and distribution of the pores of interfacially synthesized polyamide composite membrane for enhanced fraction efficiency. Tetraethyl orthosilicate (TEOS) was introduced into the porous polyamide network of the selective layer and employed to in situ generate a new silica network through space-confined hydrolysis and condensation. Membrane property including pore size distribution and separation performance was tuned by regulating the content of TEOS and systematically characterized by ATR-FTIR, XPS, SEM, AFM and cross-flow permeation test. The sol-gel of TEOS molecules confined within the selective layer was found to form a new polyamide-silica based separation layer with decreased pore size and homogenized pore size distribution. The mean size in diameter and geometric standard deviation of size distribution of the pores of the virgin polyamide based membrane were about 0.64 nm and 1.32, while those of the desired polyamide-silica based membrane obtained with a TEOS content of 3.0 v/v% were 0.59 nm and 1.26, respectively. The glucose rejection increased significantly from 58.0% of virgin polyamide membrane to 81.5% of the desired polyamide-silica based membrane. Permeation tests with concentrated mixed solution also revealed that, the desired polyamide-silica based membrane possessed better efficiency in the removal of sodium sulfate from the concentrated brine compared to the commercial membrane NF270, showing an average Na2SO4 rejection above 98.3%, a water flux around 120.0 l/m2 h, and nearly no NaCl rejection to a concentrated brine containing 200.0 g/L NaCl and 10.0 g/L Na2SO4 under 30.0 bar and 40.0 °C.

Transient Anomalous Diffusion MRI in Excised Mouse Spinal Cord: Comparison Among Different Diffusion Metrics and Validation With Histology.

Neural tissue is a hierarchical multiscale system with intracellular and extracellular diffusion compartments at different length scales. The normal diffusion of bulk water in tissues is not able to detect the specific features of a complex system, providing nonlocal, diffusion measurement averaged on a 10-20 μm length scale. Being able to probe tissues with sub-micrometric diffusion length and quantify new local parameters, transient anomalous diffusion (tAD) would dramatically increase the diagnostic potential of diffusion MRI (DMRI) in detecting collective and sub-micro architectural changes of human tissues due to pathological damage. In DMRI, the use of tAD parameters quantified using specific DMRI acquisition protocols and their interpretation has often aroused skepticism. Although the derived formulas may accurately fit experimental diffusion-weighted data, the relationships between the postulated dynamical feature and the underlying geometrical structure remains elusive, or at most only suggestive. This work aimed to elucidate and validate the image contrast and information that can be obtained using the tAD model in white matter (WM) through a direct comparison between different diffusion metrics and histology. Towards this goal, we compared tAD metrics extracted from pure subdiffusion (α-imaging) and super-pseudodiffusion (γ-imaging) in excised mouse spinal cord WM, together with T2 and T2* relaxometry, conventional (normal diffusion-based) diffusion tensor imaging (DTI) and q-space imaging (QSI), with morphologic measures obtained by optical microscopy, to determine which structural and topological characteristics of myelinated axons influenced tAD contrast. Axon diameter (AxDiam), the standard deviation of diameters (SDax.diam), axonal density (AxDens) and effective local density (ELD) were extracted from optical images in several WM tracts. Among all the diffusion parameters obtained at 9.4 T, γ-metrics confirmed a strong dependence on magnetic in-homogeneities quantified by R2* = 1/T2* and showed the strongest associations with AxDiam and ELD. On the other hand, α-metrics showed strong associations with SDax.diam and was significantly related to AxDens, suggesting its ability to quantify local heterogeneity degree in neural tissue. These results elucidate the biophysical mechanism underpinning tAD parameters and show the clinical potential of tAD-imaging, considering that both physiologic and pathologic neurodegeneration translate into alterations of WM morphometry and topology.

Molecular genetics of wool fibre structure in sheep

Abstract Methods for mapping quantitative trait loci (QTL) are actively used in the sheep to identify chromosomal regions contributing to variation in wool traits. Therefore, this paper summarises and integrates QTL studies in the sheep to identify basic information on the genetic architecture of quantitative traits relating to wool’s important traits from viewpoint of the textile industry. The number of traits, number of QTL/associations and number of related chromosomes for categories of “Fibre” and “Fleece” were 6, 78 and 18, and 5, 97 and 23, respectively. QTL list and associated single nucleotide polymorphisms (SNPs) and genes relating to fibre curvature, fibre diameter coefficient of variance, fibre diameter standard deviation, mean fibres diameter, primary fibre diameter and primary fibre diameter coefficient of variance, fleece yield, greasy fleece weight, staple length, staple strength and wool crimp are presented. This information can be helpful in identifying genes or SNPs underlying the QTL and in the application of molecular genetic information in marker-assisted breeding programs. There is complexity in identifying relationships between wool genes. Part of this complexity in the relationships between wool traits is probably related to the pleiotropic phenomenon. In general, some researchers have found markers that have not been confirmed in other published papers. False positives and false negatives in the statistical methods used can be the reason for the differences in the distinguished genes for the desired traits of wool.