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The controllable α/β ratio of Si 3 N 4 powder was synthesized using tetraethyl orthosilicate (TEOS), glucose, MgCl 2 and YCl 3 ·6H 2 O by sol-gel assisted carbothermal reduction and nitridation (CRN). This study aimed to investigate the impact of various parameters, including a H 2 O/TEOS mol ratio of the sol, a C/Si mol ratio, sintering aids, and the temperature of CRN on the phase transformation of α-Si 3 N 4. The results demonstrated that the H 2 O/TEOS ratio significantly influenced the relative content of α and β phase in Si 3 N 4 by changing the morphological characteristics of SiO 2. When the H 2 O/TEOS ratio was 100, β-Si 3 N 4 powder with an approximate β content over 88 wt% was synthesized at 1500 °C. This remarkable phase transformation was likely facilitated by the eutectic liquid phase consisting of MgSiO 3 /Mg 2 SiO 4. The SEM image revealed rod-like whiskers with a length around 1.4 μm for the β-Si 3 N 4 grains. Due to the presence of liquid phase, the synthesis of spherical-like α-Si 3 N 4 nano-powder with an α-phase content of 91 wt% was achieved at a lower temperature of 1450 °C, with an H 2 O/TEOS ratio of 15 and a C/Si ratio of 4. The size of the particles was about 70 nm due to the reduced reaction temperature. Furthermore, without the addition of any sintering aids or Si 3 N 4 seeds, high purity α-Si 3 N 4 with an α phase content approaching 96 wt% could be synthesized at 1500 °C, using an H 2 O/TEOS ratio of 15 and a C/Si ratio of 4. The resulting α-Si 3 N 4 powder exhibited an extremely regular hexagonal prism shape with a length of approximately 2 μm. [Display omitted] [ABSTRACT FROM AUTHOR]

The study of the adhesion properties between asphalt and aggregate plays a critical role in deciphering the fracture behavior and damage characteristics in asphalt mixtures. This research is dedicated to exploring the impact of various aging behaviors on adhesion properties and the reinforcing effects of modifiers. In this context, a novel composite modifier (MPM), was synthesized from phosphogypsum whisker, derived from phosphogypsum waste. Asphalt specimens, encompassing both virgin and modified asphalt with the different dosages of MPM, were prepared under a spectrum of eight aging conditions. The mechanical properties of these specimens were meticulously analyzed using multiscale tests to assess the adhesion properties under diverse aging conditions and modifier dosages. Furthermore, the study delved into the microscopic effects of aging and modification on adhesion properties. The results highlighted that aging detrimentally impacts the adhesion properties of asphalt, with this negative effect progressively intensifying over time. In contrast, the enhancement of adhesion properties by MPM exhibited variation in accordance with its dosage. Limestone, characterized by a rougher external interface and a higher prevalence of high-valent cations, demonstrated more pronounced adhesion properties to asphalt compared to granite. The aging process introduced new diffraction patterns and characteristic peaks in the asphalt, with their intensities showing a direct correlation with the duration of aging. The MPM modification was found to effectively mitigate the deterioration in the structural stability of the virgin asphalt. Overall, this study offers comprehensive insights into the aging and modification mechanisms affecting adhesion properties between asphalt and aggregate, contributing significantly to the resource utilization of solid waste. [ABSTRACT FROM AUTHOR]

Purpose of the Study: After two years of virtual meetings, the Barrels Meeting resumed to an in-person format on 10 and 11 November 2022 in La Jolla California. Materials and Methods: The meeting focused on the rodent sensorimotor system, with a focus on integrated information from the cellular to the systems level. A series of invited and selected oral presentations were delivered in addition to a poster session. Results: The latest results in the whisker-to-barrel pathway were discussed. Presentations included how the system encodes peripheral information, motor planning, and is disrupted in neurodevelopmental disorders. Conclusion: The 36th Annual Barrels Meeting brought together the research community to effectively discuss the latest advances in the field. [ABSTRACT FROM AUTHOR]

Ceramic whiskers exhibit excellent performance due to their special structure, making them widely used in the field of refractories. In this work, a novel Al 4 SiC 4 whisker was designed to improve the mechanical properties and thermal shock resistance of Al 2 O 3 –SiC–C (ASC) refractories. By introducing nickel nitrate as a catalyst, the Al 4 SiC 4 whiskers with a special "stalactite" structure could be directly grown in situ at the operating temperature of ASC (1450 °C). Combining the experimental results and first-principles calculations, the AlNi 2 Si alloy formed during the heat treatment process acted as catalyst sites, AlO, SiO and CO were easily absorbed on the Ni 55 surface. Subsequently, the Al–O, Si–O and C–O bonds were broken and reacted with each other to grow Al 4 SiC 4 whiskers according to the vapor-liquid-solid mechanism. As expected, the incorporation of Al 4 SiC 4 whiskers resulted in a 57.4 % increase in cold compressive strength (CCS) and a 47.2 % increase in residual strength ratio (RSR) of the ASC refractories due to the strengthening mechanism of whisker bridging. This study presents a novel research strategy for enhancing the properties of refractories. [ABSTRACT FROM AUTHOR]

Aluminum nitride (AlN), prized for its high thermal conductivity and electronic insulating properties, finds widespread use in electronic applications, particularly as a substrate material. However, its relatively low fracture toughness limits its application. In this study, to enhance both the thermal and mechanical properties of AlN ceramics, we thoroughly investigate the microstructure, thermal, and mechanical properties of self-reinforced AlN ceramics fabricated by spark plasma sintering, with self-reinforcement achieved through the integration of AlN whiskers within the AlN matrix. Unlike previous studies utilizing conventional pressureless sintering with limited sintering conditions, this work employs spark plasma sintering with a wide range of temperatures (1600–1900 °C) and holding times (10–30 min), providing a comprehensive understanding of the sintering behavior. Microstructural features, observed through optical and scanning electron microscopy, reveal distinct toughening mechanisms via crack deflection and branching, with a maximum 20% enhancement. The self-reinforced AlN ceramics exhibit remarkable improvements in thermal conductivity, reaching up to 150 W m−1 K−1, surpassing reported values for spark plasma-sintered AlN ceramics. Adding AlN whiskers enhances the thermal and mechanical properties of AlN simultaneously, particularly at 1800 °C for 10 min with controlled grain size and nicely integrated AlN whiskers. This work not only contributes valuable insights into the complex relationship between processing parameters, microstructure, and resulting thermal and mechanical properties but also highlights the enhanced thermal and mechanical properties of self-reinforced AlN ceramics. [ABSTRACT FROM AUTHOR]

Binderless cemented carbide has garnered attention for its exceptional hardness and suitability in extreme service conditions. The absence of a metal binder, however, leads to inadequate fracture toughness, which limits its broader application. This study explores the influence of SiC whisker on the microstructure and mechanical properties of WC-Al 2 O 3 -ZrO 2 binderless cemented carbide, utilizing a combination of experimental method and Density Functional Theory (DFT) calculations. The inclusion of 1 wt% SiC whisker resulted in a notable increase in fracture toughness, reaching an impressive toughness of 16.4 ± 0.5 MPa⋅m1/2, while maintaining a high Vickers hardness of 19.4 GPa. DFT calculations provided insights into the interface energy, cohesive energy, and charge density differences at the WC/SiC interface. This work also presents two models depicting the behavior of whiskers during fracture, based on the observed microstructure and computational findings. Overall, the present work offers significant insights and practical guidance for advancing binderless cemented carbide technologies. [ABSTRACT FROM AUTHOR]

Zirconium boride (ZrB2) whiskers hold significant potential for toughening ultra‐high temperature ceramics (UHTCs). Yet, their fabrication remains challenging due to limited knowledge of the microstructure evolution. Herein, high‐purity ZrB2 whiskers were successfully prepared by electrospinning combined with carbothermal reduction. Specifically, a precursor solution containing Zr–O–C–B networks stabilized through hydrogen bonds with polyvinyl pyrrolidone was synthesized as a spinnable ZrB2 precursor. High‐purity ZrB2 whiskers with a diameter of ca. 200 nm and a length of 5–10 µm were obtained by precise heat treatment of ZrB2 precursor fibers. In this process, ZrO2 grains formed initially and transformed into ZrB2 grains through carbothermal reduction, which further converted into ZrB2 whiskers through a solid‐liquid‐solid mechanism. To testify to the toughening effect for UHTCs, the ZrB2 whiskers were added into ZrB2 powders and followed by sintering. This strategic addition of 5 wt% ZrB2 whiskers led to a 19% enhancement in the fracture toughness of ZrB2 bulk. This study illuminated the preparation strategy and formation mechanism for ZrB2 whiskers and their application for toughening UHTCs. [ABSTRACT FROM AUTHOR]

Doped Bi2Se3 superconductors, such as CuxBi2Se3, SrxBi2Se3, NbxBi2Se3 are shown to be nematic superconductors in addition to the observed topological superconductivity. Recently it was found superconductivity in PdxBi2Se3 whiskers. The superconductivity has a residual character and probably exists on the whisker surface. The present paper deals with checking a possible nematicity existing in PdxBi2Se3 whiskers. The suppression of superconductivity was measured in the magnetic fields with induction up to 1.5 T. It was found the dependency of upper critical fields on the angle of magnetic field application. The dependency is explained in the framework of Ginzburg–Landau model and described by rather small anisotropy parameter 1.2. Besides blurring of temperature Curie near 5.3 K was observed of about 0.5 K that additionally confirmed the nematicity in PdxBi2Se3 whiskers. The rather high Curie temperature as well as nematicity existing is probably connected with strong spin–orbit interaction (SOI) of the charge carriers in the whiskers which stabilizing the superconductive state. When the temperature exceeds Tc weak antilocalization of charge carriers is observed in the whisker magnetoresistance. [ABSTRACT FROM AUTHOR]

Herpailurus yagouaroundi, popularly known as the jaguarundi cat, is a small cat with a wide territorial distribution. Understanding its morphological characteristics is of great importance for the evolution of scientific knowledge of the species and its eating habits. With that in mind, the objective was to describe the morphology of its oral cavity to contribute to future studies on its diet in captivity. Three specimens of H. yagouaroundi were used, and underwent the process of fixation in 10% formaldehyde, photodocumentation, preparation of histological slides for evaluation of lips, cheeks, hard palate, soft palate and tongue, for subsequent photomicrography. Macroscopically, the animal presented tactile hairs in the region of the cheek and close to the lips, the latter with a blackish color and smooth appearance, hard palate with wrinkles and palatine grooves full of palatine papillae, and soft palate with folds of the mucosa. The tongue had an elongated shape with different thicknesses in each region, at the apex of the tongue, filiform papillae were observed, including fungiform ones. At the base of the organ, vallate papillae, conical papillae, more delicate than the filiform ones, foliate papillae and marginal papillae were observed on the side of the tongue. Analyzing the literature, it was possible to prove that the jaguarundi cat has characteristics very similar to those of large cats. Evaluating the presence of a greater variety of lingual papillae, it is suggested that the eating habits of jaguarundi cats are more restricted and that they are more selective in their food. [ABSTRACT FROM AUTHOR]

Elephants are known for strongly lateralized trunk behaviors, but the mechanisms driving elephant lateralization are poorly understood. Here, we investigate features of elephant mouth organization that presumably promote lateralization. We find the lower jaw of elephants is of narrow width, but is rostrally strongly elongated even beyond the jaw bone. Elephant lip vibrissae become progressively longer rostrally. Thus, elephants have two lateral dense, short microvibrissae arrays and central, less dense long macrovibrissae. This is an inversion of the ancestral mammalian facial vibrissae pattern, where central, dense short microvibrissae are flanked by two lateral macrovibrissae arrays. Elephant microvibrissae have smaller follicles than macrovibrissae. Similar to trunk‐tip vibrissae, elephant lip microvibrissae show laterally asymmetric abrasion. Observations on Asian zoo elephants indicate lateralized abrasion results from lateralized feeding. It appears that the ancestral mammalian mouth (upper and lower lips, incisors, frontal microvibrissae) is shaped by oral food apprehension. The elephant mouth organization radically changed, however, because trunk‐mediated feeding replaced oral apprehension. Such elephant mouth changes include the upper lip–nose fusion to the trunk, the super‐flexible elongated lower jaw, the loss of incisors, and lateral rather than frontal microvibrissae. Elephants' specialization for lateral food insertion is reflected by the reduction in the centering effects of oral food apprehension and lip vibrissae patterns. [ABSTRACT FROM AUTHOR]

The aerospace industry requires a reliable solder with a melting point of about 240 °C that does not produce tin whiskers. The Pb–16Sn–7.5Sb-based solders, with a melting point of about 240 °C, would be the candidate solders. This paper studied the microstructure and shear strength of the Pb–16Sn–7.5Sb–xAg/Cu solder joints. The Cu3Sn formed at the interface of Pb–16Sn–7.5Sb–xAg/Cu after soldering at 260 °C. The thickness of Cu3Sn IMC is proportional to the square root of time until the SbSn phase in the solder is exhausted. Adequate Ag addition in Pb–16Sn–7.5Sb solder increases the activation energy of Cu3Sn, inhibiting the rapid growth of Cu3Sn. Therefore, after soldering for 5 min, the thickness of Cu3Sn layer in Pb–16Sn–7.5Sb/Cu solder joint is 2.2 μm, which is reduced to 1.2 μm in Pb–16Sn–7.5Sb–1Ag/Cu solder joint. The shear strength of the solder joint increases with the thickness of the Cu3Sn layer when the thickness of the Cu3Sn layer is below 1.2 μm, then decreases when the Cu3Sn layer is too thick. The solder joint, with a thin and flat Cu3Sn IMC layer, shows high shear strength. After soldering for 5 min, the shear strength of the Pb–16Sn–7.5Sb–1Ag/Cu solder joint achieves 32 MPa, about 60% higher than the Pb–16Sn–7.5Sb/Cu joint. [ABSTRACT FROM AUTHOR]

Early life experiences shape physical and behavioral outcomes throughout lifetime. Sensory circuits are especially susceptible to environmental and physiological changes during development. However, the impact of different types of early life experience are often evaluated in isolation. In this mini review, we discuss the specific effects of postnatal sensory experience, sleep, social isolation, and substance exposure on barrel cortex development. Considering these concurrent factors will improve understanding of the etiology of atypical sensory perception in many neuropsychiatric and neurodevelopmental disorders. [ABSTRACT FROM AUTHOR]

Rodents continuously move their heads and whiskers in a coordinated manner while perceiving objects through whisker-touch. Studies in head-fixed rodents showed that the ventroposterior medial (VPM) and posterior medial (POm) thalamic nuclei code for whisker kinematics, with POm involvement reduced in awake animals. To examine VPM and POm involvement in coding head and whisker kinematics in awake, head-free conditions, we recorded thalamic neuronal activity and tracked head and whisker movements in male mice exploring an open arena. Using optogenetic tagging, we found that in freely moving mice, both nuclei equally coded whisker kinematics and robustly coded head kinematics. The fraction of neurons coding head kinematics increased after whisker trimming, ruling out whisker-mediated coding. Optogenetic activation of thalamic neurons evoked overt kinematic changes and increased the fraction of neurons leading changes in head kinematics. Our data suggest that VPM and POm integrate head and whisker information and can influence head kinematics during tactile perception. Whether the posterior medial (POm) thalamic nucleus processes whisking kinematics was not clear from studies in head-fixed rodents. By studying freely moving mice, here authors demonstrate that the POm does encode whisker kinematics. Additionally, they show that both POm and the ventroposterior medial (VPM) thalamic nuclei process and can influence head kinematics. [ABSTRACT FROM AUTHOR]

Aragonite, a metastable crystal form of calcium carbonate, exhibits the highest density and hardness among all species. Diversified forms of aragonite composites can be produced through different preparation processes, forming a relatively complete system in various application fields. Their properties and applications are determined by their multiple levels of structures and shapes. However, research information for aragonite‐related fields is currently lacking integration and clarification. This review provides a comprehensive overview on the preparation methods, properties, and potential applications of three main aragonite‐based materials: aragonite particles, nacre‐inspired mineralized aragonite composites (NMACs), and shell‐derived aragonite nanoparticles (SANPs). The formation mechanisms and versatile applications of these materials are thoroughly surveyed based on their initial precursor, reaction conditions, product forms including filler of aragonite whiskers synthesized by carbonation reaction; functional materials of NMACs fabricated by amorphous calcium carbonate‐organic matter (ACC‐OM) mediated process; biomedical materials of SANPs derived from aragonite cockle shells. Overall, this review aims to provide assistance for customized production of aragonite‐based materials as well as new research directions for both pure aragonites and its composites. [ABSTRACT FROM AUTHOR]

The grazing X-ray diffraction study of phase-II NbS3 whiskers with charge density waves has shown that they exhibit pairs of broadened reflections from two close phases with the monoclinic angles β1 and β2 instead of single peaks. The phase with the smaller monoclinic angle β1 = 95.9°–97.2° is close in lattice parameters to phase I without charge density waves. Phase II with β2 = 99.9°–100.0° has a reduced b lattice parameter along the strongest bond, which implies an increased concentration of sulfur vacancies in this phase compared to phase I. It has been concluded that the studied whiskers have underwent a spinodal decomposition with the redistribution of sulfur vacancies resulting in the alternation of phases in the (001) direction perpendicular to the layers. A satellite structure indicating the formation of a superlattice with a period of 35.2 nm in this direction is observed in the most structurally perfect whisker of phase II. The spinodal decomposition is combined with high internal stresses present in whiskers with a monoclinic lattice. The partial spinodal decomposition is also observed in some phase-I whiskers without charge density waves with the appearance of thin layers of phase IV and phase II with the monoclinic angle β = 104°. The existence of thin layers of phase II in the bulk of phase I in such samples exposed to a high-frequency voltage has been confirmed by the presence of Shapiro steps on current–voltage characteristics. Spinodal decomposition should be taken into account to describe the properties of NbS3 whiskers nominally belonging to a certain polytype. [ABSTRACT FROM AUTHOR]

Changing ratios of stable carbon (δ13C) and nitrogen (δ15N) isotopes in consumer tissues reflect foraging patterns over time and can be used to inform studies on historically vulnerable populations. Northern fur seals (NFS; Callorhinus ursinus) at San Miguel Island (SMI), California, have been severely impacted by climate events such as El Niño and remain susceptible to future environmental disturbances, necessitating the need to further understand their foraging ecology. We analyzed sequential δ13C and δ15N values along single NFS whiskers sampled from five pups and five unrelated post-parturient females at SMI and reconstructed temporally aligned stable isotope profiles for each whisker. Pup profiles consistently showed increases in postnatal δ13C and δ15N values that likely stem from pup consumption of maternal milk and changes in maternal foraging locations after parturition. Adult female profiles indicated predominantly heterogeneous foraging strategies and minimal foraging outside the Southern California Bight. These findings provide initial characterizations of longitudinal, stable isotope-derived foraging data for NFS from SMI and offer insight into the inference of otariid foraging ecology with sequential δ13C and δ15N values. [ABSTRACT FROM AUTHOR]

Introduction: Herpes Zoster in humans is the result of varicella zoster virus (VZV) infection. Injecting rats with varicella zoster virus produces pain similar to herpes zoster "shingles" pain in humans.. In a previous study, orofacial pain was induced by injecting the whisker pad of male rats with VZV and the pain response increased after attenuating neurexin 3 (Nrxn3) expression in the central amygdala. Neurons descend from the central amygdala to the lateral parabrachial nucleus and orofacial pain signals ascend to the lateral parabrachial nucleus. GABAergic neurons within the central amygdala regulate pain by inhibiting activity within the lateral parabrachial nucleus. Attenuating Nrxn3 expression in the central amygdala increased GABA release in the lateral parabrachial nucleus suggesting Nrxn3 controls pain by regulating GABA release. Nrxn3 can also control synaptic connections between neurons, and we hypothesized that Nrxn3 knockdown in the central amygdala would reduce the number of GABAergic synaptic connections in the lateral parabrachial nucleus and increase VZV associated pain. Methods: To test this idea, the number of synaptic connections between GABAergic cells of the central amygdala and excitatory or dynorphin positive neurons within the lateral parabrachial nucleus were quantitated after infusion of a virus expressing synaptophysin. Synaptophysin is a synaptic vesicle protein that labels neuronal synaptic connections. These connections were measured in rats with and without whisker pad injection of VZV and knockdown of Nrxn3 within the central amygdala. Orofacial pain was measured using a place escape avoidance paradigm. Results: GABAergic synaptic connections were reduced in the lateral parabrachial nucleus after Nrxn3 knockdown. Rats with a reduction in the number of connections had an increase in VZV associated orofacial pain. Immunostaining with the pain marker prodynorphin indicated that the reduction in GABAergic connections was primarily associated with prodynorphin positive neurons. Discussion: The results suggest Nrxn3 reduces VZV associated orofacial pain, in part, by enhancing synaptic connections between GABA cells of the central amygdala and pain neurons within the lateral parabrachial nucleus. [ABSTRACT FROM AUTHOR]

Wenze Han,1,2 Ran Zhang,1,2 Shuzhi Liu,1,2 Tong Zhang,1,2 Xuemin Yao,1,2 Yuxin Cao,1,2 Jiadi Li,1,2 Xiaoming Liu,1,2 Bing Li1,2 1Shanxi Medical University School and Hospital of Stomatology, Taiyuan, Shanxi, 030001, People’s Republic of China; 2Shanxi Province Key Laboratory of Oral Diseases Prevention and New Materials, Taiyuan, 030001, Shanxi, People’s Republic of ChinaCorrespondence: Xiaoming Liu; Bing Li, Shanxi Medical University School and Hospital of Stomatology, Taiyuan, Shanxi, 030001, People’s Republic of China, Email lxming0912@163.com; libing1975vip@163.comAbstract: Whiskers are nanoscale, high-strength fibrous crystals with a wide range of potential applications in dentistry owing to their unique mechanical, thermal, electrical, and biological properties. They possess high strength, a high modulus of elasticity and good biocompatibility. Hence, adding these crystals to dental composites as reinforcement can considerably improve the mechanical properties and durability of restorations. Additionally, whiskers are involved in inducing the value-added differentiation of osteoblasts, odontogenic osteocytes, and pulp stem cells, and promoting the regeneration of alveolar bone, periodontal tissue, and pulp tissue. They can also enhance the mucosal barrier function, inhibit the proliferation of tumor cells, control inflammation, and aid in cancer prevention. This review comprehensively summarizes the classification, properties, growth mechanisms and preparation methods of whiskers and focuses on their application in dentistry. Due to their unique physicochemical properties, excellent biological properties, and nanoscale characteristics, whiskers show great potential for application in bone, periodontal, and pulp tissue regeneration. Additionally, they can be used to prevent and treat oral cancer and improve medical devices, thus making them a promising new material in dentistry.Keywords: whiskers, dentistry, growth mechanism, biomaterials

Conca and Varbaro (2020) [7] showed the equality of depth of a graded ideal and its initial ideal in a polynomial ring when the initial ideal is square-free. In this paper, we give some beautiful applications of this fact in the study of Cohen-Macaulay binomial edge ideals. We prove that for the characterization of Cohen-Macaulay binomial edge ideals, it is enough to consider only "biconnected graphs with some whisker attached" and this is done by investigating the initial ideals. We give several necessary conditions for a binomial edge ideal to be Cohen-Macaulay in terms of smaller graphs. Also, under a hypothesis, we give a sufficient condition for Cohen-Macaulayness of binomial edge ideals in terms of blocks of graphs. Moreover, we show that a graph with Cohen-Macaulay binomial edge ideal has girth less than 5 or equal to infinity. [ABSTRACT FROM AUTHOR]

Fragile X syndrome (FXS) is caused by epigenetic silencing of the X-linked fragile X messenger ribonucleoprotein 1 (FMR1) gene located on chromosome Xq27.3, which leads to the loss of its protein product, fragile X messenger ribonucleoprotein (FMRP). It is the most prevalent inherited form of intellectual disability and the highest single genetic cause of autism. Since the discovery of the genetic basis of FXS, extensive studies using animal models and human pluripotent stem cells have unveiled the functions of FMRP and mechanisms underlying FXS. However, clinical trials have not yielded successful treatment. Here we review what we have learned from commonly used models for FXS, potential limitations of these models, and recommendations for future steps. [ABSTRACT FROM AUTHOR]

Rodents rely on their whiskers as vital sensory tools for tactile perception, enabling them to distinguish textures and shapes. Ensuring the reliability and constancy of tactile perception under varying stimulus conditions remains a fascinating and fundamental inquiry. This study explores the impact of stimulus configurations, including whisker movement velocity and object spatial proximity, on texture discrimination and stability in rats. To address this issue, we employed three distinct approaches for our investigation. Stimulus configurations notably affected tactile inputs, altering whisker vibration's kinetic and kinematic aspects with consistent effects across various textures. Through a texture discrimination task, rats exhibited consistent discrimination performance irrespective of changes in stimulus configuration. However, alterations in stimulus configuration significantly affected the rats' ability to maintain stability in texture perception. Additionally, we investigated the influence of stimulus configurations on cortical neuronal responses by manipulating them experimentally. Notably, cortical neurons demonstrated substantial and intricate changes in firing rates without compromising the ability to discriminate between textures. Nevertheless, these changes resulted in a reduction in texture neuronal response stability. Stimulating multiple whiskers led to improved neuronal texture discrimination and maintained coding stability. These findings emphasize the importance of considering numerous factors and their interactions when studying the impact of stimulus configuration on neuronal responses and behavior. [ABSTRACT FROM AUTHOR]

Cytoarchitecture, the organization of cells within organs and tissues, serves as a crucial anatomical foundation for the delineation of various regions. It enables the segmentation of the cortex into distinct areas with unique structural and functional characteristics. While traditional 2D atlases have focused on cytoarchitectonic mapping of cortical regions through individual sections, the intricate cortical gyri and sulci demands a 3D perspective for unambiguous interpretation. In this study, we employed fluorescent micro-optical sectioning tomography to acquire architectural datasets of the entire macaque brain at a resolution of 0.65 µm × 0.65 µm × 3 µm. With these volumetric data, the cortical laminar textures were remarkably presented in appropriate view planes. Additionally, we established a stereo coordinate system to represent the cytoarchitectonic information as surface-based tomograms. Utilizing these cytoarchitectonic features, we were able to three-dimensionally parcel the macaque cortex into multiple regions exhibiting contrasting architectural patterns. The whole-brain analysis was also conducted on mice that clearly revealed the presence of barrel cortex and reflected biological reasonability of this method. Leveraging these high-resolution continuous datasets, our method offers a robust tool for exploring the organizational logic and pathological mechanisms of the brain's 3D anatomical structure. [ABSTRACT FROM AUTHOR]

The CNTs/MgAl2O4 whiskers composite reinforcement was prepared by catalytic carbon‐bed sintering and added to low‐carbon Al2O3‐C refractories to enhance the thermal shock resistance of refractories. The effects of Ni(NO3)2·6H2O content on the phase and microstructure of CNTs/MgAl2O4 were investigated. The nano‐indentation technology was used to quantitatively evaluate the effect of CNTs/MgAl2O4 on the thermal shock resistance of low‐carbon Al2O3‐C refractories, and the toughening mechanism of CNTs/MgAl2O4 on refractories was further investigated. The results revealed that the inner and outer diameters of the CNTs were approximately 5.69 and 16.26 nm, respectively. The CNTs winded around interlocking structural MgAl2O4 whiskers with a high aspect ratio (>100), which was beneficial to the dispersion of CNTs in the refractory matrix. The thermal shock resistance of low‐carbon Al2O3‐C refractories was significantly improved by adding 3.0 wt.% of CNTs/MgAl2O4 (named C3). The specific fracture energy of refractory matrix and residual strength ratio of C3 reached 141 N·m−1 and 39.2%, which were 29.4% and 97.0% higher than those of the blank sample (109 N·m−1 and 19.9%), respectively. This is because the refractory matrix was significantly reinforced by CNTs and MgAl2O4 whiskers, promoting the occurrence of "bridging" and "crack deflection" and the generation of microcracks in the refractory matrix. [ABSTRACT FROM AUTHOR]

Asphalt modification with inorganic whiskers is a novel and green method to improve the performance of asphalt pavement, but it is still limited by the high costs and uneven dispersion of whiskers. In this study, an innovative asphalt modifier that can in-situ generate whiskers in hot mix asphalt (HMA) was developed by the alkali activation method using waste dolomite dust as raw material. The morphology and distribution of the alkali-activated waste dolomite dust (AWD) whiskers were examined by scanning electron microscopy and fluorescence microscopy, and the effects of AWD curing time, processing mode and dosage on the rheological and adhesion properties of the modified asphalt binder were evaluated. The results indicate that AWD can spontaneously form whiskers in the asphalt matrix under the flowing temperature of HMA, and the optimal performance enhancement effect on asphalt binder is achieved when the AWD curing time is 1 day, and its dosage is 5% of the asphalt binder mass. Compared with neat binder, the modified binder with AWD shows a 65% increase in rutting factor and a 2-level improvement in adhesion grade, while the costs of AWD are only 1/27 of those of commercial CaCO3 whiskers. These findings demonstrate that AWD is a cost-effective, eco-friendly and high-performance asphalt modifier, which has great potential for application in asphalt pavement engineering. [ABSTRACT FROM AUTHOR]

As a result of thermal cycling, polycrystalline tin films with a large in-plane grain size relative to film thickness on copper substrates show grain boundary (GB) sliding, creep, yielding, and nucleation of shallow grains that become whiskers. These microstructural changes occur near GBs, with different types of changes for different GBs. To understand these different phenomena, it is important to identify local microstructural changes and signatures of deformation mechanisms on free surfaces as deformation progresses, particularly in how they affect the formation of shallow grains. This study does that by characterizing the evolution of morphological, crystallographic, and curvature changes near GBs in large-grained Sn films during rapid thermal cycling. The observed responses include (1) nucleation of new grains accompanied by local yielding as indicated by slip band formation and grain misorientation changes, (2) GB sliding and diffusion, and (3) localized GB migration, with GB sliding and near-GB rotation occurring earlier than other phenomena. The angles between slip planes and observed slip traces suggested that dislocations moved along activated slip planes to form new GBs. These results on large-grained bicrystal films provide insights into the complex stress relaxation behavior of columnar polycrystalline tin films under the same thermal cycling conditions. [ABSTRACT FROM AUTHOR]

Objective: This preliminary study suggests a way to artificially extend vibrissae of blind dogs to assist ambulation and avoiding facial contact with obstacles. Procedures: Fourteen irreversibly blind dogs had 5–6 mystacial vibrissae on each side of the face supplementally extended by attaching carefully chosen adult pig hairs to them and were subjected to a maze test before and after the procedure. In three of these dogs the test was repeated one more time after all the extensions had fallen off. Collision counts and course times with and without extensions were analyzed and compared. A p-value > 0.05 was considered significant. Results: Median number of collisions was significantly higher post-extensions (5 IQR 2.25) and after extensions had fallen off (4 IQR 7.50) compared to pre-extensions (1 IQR 1), p = 0.021. Median times were significantly higher pre-extension (25.6 IQR 8.98) and after the extensions had fallen off, compared to the post-extension performance (22.8 IQR 8.55), p = 0.04. Conclusion: Vibrissae play an important role in the tactile perception of blind dogs, and our preliminary results suggest that extending this sensory organ possibly improves obstacle location and their quality of life. [ABSTRACT FROM AUTHOR]

A version 2.0Z testing system using the double whisker photoelectric method was developed. Twenty-five kinds of carding cashmere samples were tested by double whisker photoelectric method. The accuracy and stability of the 2.0Z test system were verified by comparing the test results of the hand row method in GB 18267-2013. The results show that there are differences among samples and the sample size of hand-row method is small, so the random error is high, while the results of the double whisker photoelectric method are relatively stable. The double whisker photoelectric method 2.0Z test system has a high consistency with the hand row method. In particular, the average deviation of the mean length index is less than 2 mm, and the correlation coefficient is greater than 0.8. The double whisker photoelectric method 2.0Z test system has a high accuracy. [ABSTRACT FROM AUTHOR]

Long Ag and Cu whiskers are found in Ag–Cu–Te alloys annealed at 400 and 600 °C. Depending upon the nominal compositions of the alloys, there are three kinds of whiskers, Ag, Cu, and Ag + Cu whiskers. For the first time, two different kinds of whiskers grown simultaneously from the same substrate are observed. These whiskers are all polycrystalline, and the grain sizes of the Ag are larger than those of Cu. As indicated by their continuous connection with the substrate, many shear bands in the whiskers, and low-angle grain boundaries piling up near the grain boundaries, it is confirmed that the whiskers grow not from the gas phase, but within the solid state, pushed outward by stress. The Ag–Cu–Te liquidus projection is calculated by the Calphad method. It is found that the compositional regimes of whisker growth overlap with the regions of the liquid miscibility gaps. When alloys solidify through a liquid miscibility gap, two regions of different compositions would form. The stress developed following solidification, originating from these two regions of different compositions, is the main driving force behind whisker formation. The rapid growth rates of the whiskers are a result of the rapid liquid-like diffusion behaviors of the Ag and Cu atoms in the Ag–Cu–Te alloys of the cage-like structures. [ABSTRACT FROM AUTHOR]

Historically known as neuronal support cells, astrocytes are now widely studied for their close structural and functional interactions with multiple neural cell types and cerebral vessels where they maintain an ideal environment for optimized brain function. Under pathological conditions, astrocytes become reactive and lose key protective functions. In this commentary, we discuss our recent work in The Journal of Neuroscience (Sompol et al., 2023) that showed Ca2+ dysregulation in reactive astrocytes, as well as hyperactivation of the Ca2+-dependent protein phosphatase calcineurin (CN) and the Nuclear Factor of Activated T Cells (NFATs), in a diet-induced hyperhomocystienemia (HHcy) mouse model of Vascular Contributions to Cognitive Impairment and Dementia (VCID). Intravital multiphoton imaging coupled with whisker stimulation was used to explore astrocyte Ca2+ signaling and neurovascular function under active phase, fully awake conditions. Interestingly, evoked Ca2+ transients in individual astrocytes were greater, even though intercorrelated Ca2+ signaling across networks of astrocytes was impaired in HHcy mice. Blockade of astrocytic CN/NFAT reduced signs of astrocyte reactivity, normalized cerebrovascular function, and improved hippocampal synaptic strength and hippocampal dependent cognition in HHcy mice, revealing a previously unrecognized deficit regarding neuron-astrocyte-vascular interactions. These findings strongly support the use of astrocyte targeting strategies to mitigate pathophysiological changes associated with VCID and other Alzheimer's-related dementias. [ABSTRACT FROM AUTHOR]

Sensory neurons reconstruct the world from action potentials (spikes) impinging on them. To effectively transfer information about the stimulus to the next processing level, a neuron needs to be able to adapt its working range to the properties of the stimulus. Here, we focus on the intrinsic neural properties that influence information transfer in cortical neurons and how tightly their properties need to be tuned to the stimulus statistics for them to be effective. We start by measuring the intrinsic information encoding properties of putative excitatory and inhibitory neurons in L2/3 of the mouse barrel cortex. Excitatory neurons show high thresholds and strong adaptation, making them fire sparsely and resulting in a strong compression of information, whereas inhibitory neurons that favour fast spiking transfer more information. Next, we turn to computational modelling and ask how two properties influence information transfer: 1) spike-frequency adaptation and 2) the shape of the IV-curve. We find that a subthreshold (but not threshold) adaptation, the 'h-current', and a properly tuned leak conductance can increase the information transfer of a neuron, whereas threshold adaptation can increase its working range. Finally, we verify the effect of the IV-curve slope in our experimental recordings and show that excitatory neurons form a more heterogeneous population than inhibitory neurons. These relationships between intrinsic neural features and neural coding that had not been quantified before will aid computational, theoretical and systems neuroscientists in understanding how neuronal populations can alter their coding properties, such as through the impact of neuromodulators. Why the variability of intrinsic properties of excitatory neurons is larger than that of inhibitory ones is an exciting question, for which future research is needed. Author summary: Intracellular information transfer from synaptic input to output spike train is necessarily lossy. Here, we explicitly measure the mutual information between a neuron's input and spike output and show that information transfer is more lossy and heterogeneous for excitatory than for inhibitory neurons. By using computational modelling we show that the shape of the input-output curve as well as how fast a neuron adapts to its input collectively determine the rate of information loss. These insights will help both experimentalists and modellers in designing and simulating experiments that investigate how network coding properties can adapt to the environment, for instance through the effects of neuromodulators. [ABSTRACT FROM AUTHOR]

The rapid development of micro-electronics has a growing demand on the heat dissipation performance of devices, especially thermal management materials. However, recent researches focus on the improvement of single ability, such as thermal or mechanical properties. Herein, a strategy that simultaneously improves thermal and mechanical performance of thermal manager material was proposed, which was achieved by preparing Cu-SiC w composites via the co-electrodeposition technology. The influence of electroplating parameters, such as temperature, current density and reinforcement contents, on the microstructure evolution, mechanical and thermal conductivity were investigated systematically. The fabricated SiC w composite displayed excellent shear strength up to 420 MPa, which is resulted from the Orowan strengthening and load transferring. Additionally, the thermal conductivity of 340 W/(m·K) was obtained, owing to the uniform distribution of whiskers and good interface between the Cu matrix and whiskers. Therefore, the presented work provided an effective method for fabricating comprehensive thermal-mechanical properties and homogeneous heat dissipation capacity Cu-SiC w composites and paved the way for the practical application in the field of the connector between the power devices and heat sinks. [ABSTRACT FROM AUTHOR]

Given the importance of information on intrauterine development in diagnosing anomalies in the gestational development of the species for the development of assisted reproduction technologies as well as understanding the autonomy and responsiveness of the newborn, the aim of the present study was to describe the external morphology of collared peccary conceptuses. For this study, two conceptuses were used per gestational age of 25–120 days post‐copulation (dpc) and neonates with 145 dpc, totalling 22 animals. Females were euthanised, and embryos/foetuses were examined, measured, and photographed. During the first third of the gestational period (25–50 dpc, n = 8), a marked body curvature, brain vesicles, somites, internal organs, placid lens, auricular protrusion and limb buds are noted. In the second third of the gestational period (51–100 dpc, n = 10), foetuses lose their body curvature, displaying greater anatomical definition, including skeletal, external ears, nostrils, eyelids and tactile hair formation and cranial suture closure. In addition, dorsal scent gland and genital tubercle differentiation were visualized at 50 days post‐copulation. In the third of the gestational period (101–145 dpc, n = 4), the organs become completely formed, alongside skin darkening, eyelid opening, dental eruption, dorsal odorous gland development, sexual organ externalization, and fanero attachment development. These data allowed for the construction of a prenatal growth curve, providing comparative anatomy information for ungulates and further contributing towards rational reproductive management and reproductive biotechnologies for this species. [ABSTRACT FROM AUTHOR]

A method of Al 2 O 3 whiskers addition is provided to simultaneously enhance the forming accuracy, and mechanical and tribological performances of translucent glass-ceramics manufactured through vat photopolymerization 3D printing. Al 2 O 3 whiskers (0–15 wt%) were added to a self-prepared fluorapatite glass-ceramic as a raw material. The results demonstrated that the addition of Al 2 O 3 whiskers significantly improved the forming accuracy, mechanical and tribological performances of fluorapatite (FAp) glass-ceramics. The dimensional error of the formed samples decreased by approximately 56% with the addition of 15 wt% Al 2 O 3 whiskers. The glass-ceramics containing 10 wt% Al 2 O 3 whiskers exhibited a flexural strength and fracture toughness of 220.3 ± 13.7 MPa and 1.81 ± 0.18 MPa·m1/2, respectively, representing a 44.1% and 111.8% increase compared to pure FAp glass-ceramics. Furthermore, the addition of Al 2 O 3 whiskers led to reduced wear volume in both the glass-ceramics and titanium balls used as counterparts, indicating improved tribological compatibility. [ABSTRACT FROM AUTHOR]

Mullite-bonded SiC porous ceramics are of potential in hot gas infiltration while the insufficient mechanical performance limits its application. In-situ mullite whisker reinforcement is a potential solution but the formation temperature mismatch between mullite whisker and bonding layer is a challenge. In that case, mullite whiskers massively form ahead of the bonding layer excessively consuming alumina leading to poor bonding layers between SiC particles and thus, the mechanical performance. Herein, the mismatch was solved by using CaF 2 as a temperature-controlled reaction switch. As a result, both the bonding layer and whisker synchronously formed. The material showed significant reinforcement effects, and exhibited a flexural strength of 124.8 MPa and a fracture toughness of 1.53 MPa·m1/2 with an open porosity of 36.6 vol%, realizing a breakthrough in the mechanical performance. Interestingly, an increase in oxygen vacancy concentration with the sintering temperature was first reported, which may benefit the whisker growth. [ABSTRACT FROM AUTHOR]

Mercury (Hg) tailings are hazardous solid wastes because of their high Hg concentrations. Modified phosphogypsum (PG) can decrease the bioactivity and mobility of heavy metals through chemisorption or electrostatic interactions. In this study, PG whiskers were modified by ZnCl2 and S, chitosan-hydrochloric acid, and thioglycolic materials; the resulting modified whiskers were used to decontaminate Hg tailings. Leaching tests and orthogonal experiments were conducted to optimize the modification parameters, including modifier quantity, pH, reaction temperature, and reaction time. The structure and physicochemical properties of the whiskers before and after modification were characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The stabilization efficiency of the modified PG whiskers ranged from 93.05 to 97.50%, demonstrating excellent stabilization effects. The stabilization was achieved through chemisorption or complexation. The decontamination process using modified whiskers reduced the pH and total nitrogen of the tailings; increased the cation exchange, total phosphorus, organic carbon, and total carbon; and made the tailings suitable for planting. In addition, the modified PG promoted the morphological transformation of Hg in the tailings, thereby significantly decreasing the Hg content in the effective states and mitigating the risk of Hg contamination. [ABSTRACT FROM AUTHOR]

This study centers on a novel approach of high flexural strength rankinite (3CaO·2SiO2, abbreviated as C3S2) cement benefiting from in-situ formation of aragonite whisker (AW) during carbonation curing. The manufacturing parameters including MgCl2 concentration and reaction temperature play key influence on formation of AW. The results showed that high temperature favored AW formation and AW with length-diameter ratio of 15 ∼ 30 could be generated with concentration of Mg2+/Ca2+ molar ratio of 0.1 at 70 °C. Under this condition, the flexural strength of the C3S2 cement reached 7.5, and 15.6 MPa after 3d and 28d and the corresponding compressive strengths were 30.2 and 71.1 MPa, respectively. The results also showed that 40.9% of CO2 by mass was consolidated in rankinite paste after 48 h, suggesting a promising prospect for calcium silicate-containing waste residue and cement to capture CO2 and simultaneously manufacturing high-performance materia. [ABSTRACT FROM AUTHOR]

Hair shape affects the frictional properties and tactile sensation of hair. In this study, we evaluated the friction associated with the rubbing of straight, curly, or wavy hair by a contact probe equipped in a sinusoidal motion friction evaluation system. This system provides dynamic information such as the velocity dependence and hysteresis of the frictional force. In the case of hair fibers fixed at 1 mm intervals on a glass plate, a stable friction pattern was observed, in which the friction coefficient was almost constant during the dynamic friction process. The friction coefficients in the inward direction toward the hair root for straight, curly, and wavy hair were 0.47 ± 0.04, 0.51 ± 0.02, and 0.54 ± 0.04, respectively. As wavy hair is thick and has a larger true contact area with the contact probe, the friction coefficient was larger. When the finger model rubbed the straight or curly hair bundle in the inward direction, an oscillation pattern was observed, with the friction coefficient fluctuating at 20 ms intervals and the kinetic friction coefficient evaluated at 0.67 and 0.64, respectively. For the surface of straight hair, containing densely arranged cuticles, a large oscillation was observed in the direction against the cuticles. Meanwhile, no oscillation phenomenon was observed in wavy hair, which is characterized by a smooth cuticle and complex hair flow. Because wavy hair, which is frizzy, has fewer points of contact between hairs, impeding the occurrence of cooperative fluctuations in the frictional force. [ABSTRACT FROM AUTHOR]

• Imaging Robo3cKO mouse cortex with bilateral whisker representation. • S1 to M1 and Prefrontal Cortex projections. • Bilateral whisker representation in the M1 cortex of Robo3 cKO mice. In Robo3cKO mice, midline crossing defects of the trigeminothalamic projections from the trigeminal principal sensory nucleus result in bilateral whisker maps in the somatosensory thalamus and consequently in the face representation area of the primary somatosensory (S1) cortex (Renier et al., 2017; Tsytsarev et al., 2017). We investigated whether this bilateral sensory representation in the whisker-barrel cortex is also reflected in the downstream projections from the S1 to the primary motor (M1) cortex. To label these projections, we injected anterograde viral axonal tracer in S1 cortex. Corticocortical projections from the S1 distribute to similar areas across the ipsilateral hemisphere in control and Robo3cKO mice. Namely, in both genotypes they extend to the M1, premotor/prefrontal cortex (PMPF), secondary somatosensory (S2) cortex. Next, we performed voltage-sensitive dye imaging (VSDi) in the left hemisphere following ipsilateral and contralateral single whisker stimulation. While controls showed only activation in the contralateral whisker barrel cortex and M1 cortex, the Robo3cKO mouse left hemisphere was activated bilaterally in both the barrel cortex and the M1 cortex. We conclude that the midline crossing defect of the trigeminothalamic projections leads to bilateral whisker representations not only in the thalamus and the S1 cortex but also downstream from the S1, in the M1 cortex. [ABSTRACT FROM AUTHOR]

The development and design of fillers aid in improving the tribological performances of friction materials. Herein, the effects of the aspect ratio of mullite whisker on the tribological properties were studied. Mullite whiskers were prepared by the sol–gel process and the aspect ratio of the whisker was controlled by introducing aluminum fluoride (AlF3). The aspect ratio increased significantly at first and then decreased with increasing the contents of AlF3. The experimental results show that higher aspect ratio whiskers stabilized the friction coefficient while increased the wear rate. In addition, the composite with mullite whisker grown in excessive AlF3 (20%) resulted in a higher friction coefficient compared to adding inadequate AlF3 (10%). The Scanning Electron Microscope (SEM) and Energy Dispersive X‐Ray Spectroscopy (EDX) results indicated that higher aspect ratio of whisker was more likely to fall off from matrix which sequentially being compacted and formed contact plateaus during the friction process. In conclusion, it was found that abrasive wear and adhesive wear were the dominant wear mechanism. Highlights: The aspect ratio of mullite whisker was controlled within the range of 6 ~ 21.The tribological properties of whiskers reinforced composites were studied.The morphology of the mullite whisker affects the friction stability.The flaky mullite whisker can improve wear resistance of the composites. [ABSTRACT FROM AUTHOR]

Heterocyclic aramid fibers (HAFs) with high strength and high modulus are widely used in the field of impact resistance. However, the weak interaction between molecular chains of HAFs seriously hinders the simultaneous improvement of strength and modulus. Herein, small addition (0.05 wt%) of nanosized acyl‐chloride‐activated graphene whiskers (NGW‐Cl) is used as reinforcements to simultaneously increase the strength and modulus of HAFs. The resultant NGW‐Cl/HAFs monofilament displays high tensile strength and modulus of 6.31 and 152 GPa, which are 19% and 18.8% higher than that of HAFs. The NGW‐Cl/HAFs multifilaments show high tensile strength and modulus of 36.16 and 1008 cN per dtex, which are 19.34% and 24.14% higher than that of HAFs. Especially, the dynamic modulus of NGW‐Cl/HAFs is up to 268.0 GPa at 200 HZ, which is increased by 92.8% compared with HAFs (139.0 GPa), showing a great application potential in high‐frequency vibration fields. Additionally, the strength and modulus of NGW‐Cl/HAFs impregnated multifilaments is up to 6.08 and 152 GPa, which is increased by 24.5% and 28.8% compared with HAFs. This apparent improvement is because the strong chemical bonding between NGW‐Cl and heterocyclic aromatic chains enhances heterocyclic aromatic chain interaction, inducing high crystallinity and orientation of HAFs. [ABSTRACT FROM AUTHOR]

Biodegradable composite films comprising of poly(butylene adipate-co-terephthalate) (PBAT), polylactic acid (PLA), and tetrapod-zinc oxide (T-ZnO) whisker were prepared by a melt-extrusion and blow molding process. The effect of the incorporation of the T-ZnO whisker (1 to 7 wt.%) in the PBAT/PLA blend film was studied systematically. The composite films with an optimal T-ZnO whisker concentration of 3 wt.% exhibited the highest mechanical (tensile strength ~32 MPa), rheological (complex viscosity~1200 Pa.s at 1 rad/s angular frequency), and gas barrier (oxygen permeability~20 cc/m2·day) properties, whereas the composite films with 7 wt.% T-ZnO whiskers exhibited the highest antibacterial properties. The developed composite films can find potential application as antibacterial food packaging materials. [ABSTRACT FROM AUTHOR]

This study aims to characterize the mechanical response of thick Al whiskers under tension. Wire‐shaped whiskers are fabricated by stress‐induced migration using an original sample structure. Straight and single‐crystal whiskers are suspended between a W probe tip attached to a micromanipulator and an atomic force microscope tip attached to a nanostage using electron beam irradiation hardening glue. Tensile tests are conducted by pulling the probe tip. A tensile strength of 1 GPa is obtained for a whisker with a diameter of 500 nm. Observations using a high‐voltage electron microscope show that the whisker is deformed by pencil‐shaped sharp necking with signs of recrystallization at the tip, which displays a novel mechanical response of Al whiskers. The obtained tensile strength is more than twice that of whiskers with similar diameters reported in the literature, indicating that the tensile strength of not only thin, but also thick whiskers can be enhanced by activating a different mode of deformation. [ABSTRACT FROM AUTHOR]

Tactile sensation and vision are often both utilized for the exploration of objects that are within reach though it is not known whether or how these two distinct sensory systems combine such information. Here in mice, we used a combination of stereo photogrammetry for 3D reconstruction of the whisker array, brain-wide anatomical tracing and functional connectivity analysis to explore the possibility of tacto-visual convergence in sensory space and within the circuitry of the primary visual cortex (VISp). Strikingly, we find that stimulation of the contralateral whisker array suppresses visually evoked activity in a tacto-visual sub-region of VISp whose visual space representation closely overlaps with the whisker search space. This suppression is mediated by local fast-spiking interneurons that receive a direct cortico-cortical input predominantly from layer 6 neurons located in the posterior primary somatosensory barrel cortex (SSp-bfd). These data demonstrate functional convergence within and between two primary sensory cortical areas for multisensory object detection and recognition. Where and how the brain integrates discrete sensory inputs is not fully understood. Here authors show that a multisensory zone in the mouse anterior primary visual cortex integrates tactile and visual inputs from a shared sensory space through interareal feedforward inhibition. [ABSTRACT FROM AUTHOR]

Ecological theory predicts niche partitioning between high-level predators living in sympatry as a mechanism to minimise the selective pressure of competition. Accordingly, male Australian fur seals Arctocephalus pusillus doriferus and New Zealand fur seals A. forsteri that live in sympatry should exhibit partitioning in their broad niches (in habitat and trophic dimensions) in order to coexist. However, at the northern end of their distributions in Australia, both are recolonising their historic range after a long absence due to over-exploitation, and their small population sizes suggest competition should be weak and may allow overlap in niche space. We found some niche overlap, yet clear partitioning in diet trophic level (δ15N values from vibrissae), spatial niche space (horizontal and vertical telemetry data) and circadian activity patterns (timing of dives) between males of each species, suggesting competition may remain an active driver of niche partitioning amongst individuals even in small, peripheral populations. Consistent with individual specialisation theory, broad niches of populations were associated with high levels of individual specialisation for both species, despite putative low competition. Specialists in isotopic space were not necessarily specialists in spatial niche space, further emphasising their diverse individual strategies for niche partitioning. Males of each species displayed distinct foraging modes, with Australian fur seals primarily benthic and New Zealand fur seals primarily epipelagic, though unexpectedly high individual specialisation for New Zealand fur seals might suggest marginal populations provide exceptions to the pattern generally observed amongst other fur seals. [ABSTRACT FROM AUTHOR]

In present work, the novel Al2O3-C ceramic filter fabricated by using microporous corundum-spinel powder instead of dense Al2O3 powder and reinforced by SiC whiskers is proposed. The effects of Si powder content (0, 3, 6, and 9 wt. %) on the microstructures and mechanical properties of the filters were studied. After replacing the α-Al2O3 micro-powder with microporous corundum-spinel powder, the in situ spinel whiskers were formed inside the filter skeleton under the reducing atmosphere. The rough surface structure of the microporous powder increased the interface contact area with the small-sized carbon particles, resulting in a compact interface bonding in the filter skeleton and a higher cold compressive strength of the filter. When the Si powder content increased to 6-9 wt. %, the in-situ SiC whiskers were formed not only between the microporous powder, but also inside the pores near the surface of it by vapor-solid reaction mechanism in the filter skeleton. The SiC whiskers synergized with the microporous powder to form a more compact interface structure, thus remarkably enhancing their cold compressive strength and thermal shock resistance. Overall, the mechanical properties of the filters were significantly improved by the addition of 9 wt. % Si powder. The filter skeleton had an apparent porosity of 36.2% and a bulk density of 1.93 g/cm³. The filter also exhibited a high cold compressive strength of 1.59 MPa and a superior thermal shock resistance. It has the potential for better purification efficiency on molten steel in the future due to a rougher skeleton surface structure compared to existing Al2O3-C filters. [ABSTRACT FROM AUTHOR]

Huiyi Yao,1 Wenzhong Xiang2 1Department of Dermatology, Zhejiang Chinese Medical University, Hangzhou Third People’s Hospital, Hangzhou, People’s Republic of China; 2Department of Dermatology, Hangzhou Third People’s Hospital, Hangzhou Third People’s Hospital Affiliated to Zhejiang Chinese Medical University, Hangzhou, People’s Republic of ChinaCorrespondence: Wenzhong Xiang, Department of Dermatology, Hangzhou Third People’s Hospital, Hangzhou Third People’s Hospital Affiliated to Zhejiang Chinese Medical University, Westlake Ave 38, Hangzhou, 310009, People’s Republic of China, Tel +86 13588004268, Email xiangwenzhong@126.comAbstract: Becker’s nevus (BN) is a kind of epidermal cutaneous hamartoma. A noticeable hyperpigmented patch with a big, unilateral, hyperpigmented macule and irregularly shaped borders is the manner in which BN often presents. In this case, a 16-year-old boy has asymptomatic dark brown colored follicular macule on the left side of the cheek shortly after birth. The lesions were initially inconspicuous but gradually became darker as time passed. The macules on some of them grew hair. This case of BN with apparent hypertrichosis on one side of the cheek, which made it challenging to make a differential diagnosis with whiskers. The primary point of differentiation is that the lesions of BN only appear unilaterally. On the other hand, the face has whiskers on both sides. Additionally, BN will show hyperpigmentation whereas whiskers do not. In conclusion, for its unusual clinical presentation, we believe that reporting this case may help dermatologists avoid misdiagnosing similar cases.Keywords: Becker’s nevus, misdiagnosed, whiskers, hypertrichosis

In this study, the whisker structure of a harbor seal is applied to the lip and the trailing edge of a turbine cooling blade with a pressure-side cutback. Four cases are studied in this article, including a prototype, a whisker trailing edge, a PP (The lip's peak and the trailing edge's peak are designed at the same blade height) case, and a PV (The lip's peak and the trailing edge's valley are designed at the same blade height) case. The DDES method is used to simulate the flow and thermal mixing process in the cascade. The coolant mass flow ratios ( c m ) of 0.5% and 1% at an outlet Mach number of 0.9 are simulated. The PP case can achieve the best aerodynamic performance, which reduces the thermodynamic energy loss coefficient of the prototype by 0.98% and 0.99% at c m = 0.5% and c m = 1%, respectively. The PP case and the PV case increase the lowest spanwise average adiabatic film cooling effectiveness on the cutback surface from 0.5 to 0.7 at c m = 0.5%. The film cooling effectiveness of the PP case and the PV case can remain close to 1 over the entire cutback surface at c m = 1%. The PP case transforms the trailing edge shedding vortices on the pressure side into hairpin vortices. The whisker lip suppresses the lip vortex and alters the closed separation bubble on the cutback surface, causing the coolant to converge toward Section 1. The convergence of coolant is more helpful for the PP case to control the pressure side shedding vortex, resulting in a lower thermodynamic energy loss. [ABSTRACT FROM AUTHOR]

Silicon nitride (Si3N4) has great potential for applications in photoelectric and semiconductor fields. In this study, a novel strategy of fabricating Si3N4 crystals is reported, and the morphology of α-Si3N4 can be controlled. The aBN/SiO2/Si wafers were designed and irradiated by a high-energy electron beam for 2 min using home-made equipment. Tree-like α-Si3N4 dendrites and [001]-oriented unbranched α-Si3N4 whiskers can be synthesized by controlling the electron beam energy. Related formation mechanisms were analyzed based on componential and structural characterization using a scanning electron microscope and high-resolution transmission electron microscope. In addition, photoluminescence measurements indicate that the synthesized α-Si3N4 exhibit unique photoluminescence properties. This is attributed to α-Si3N4 forming abundant Si–Si bonds, Si dangling bonds, N dangling bonds and oxygen bonds in the synthesis process. These findings provide new insights into fabricating high-quality Si3N4 crystals, as well as developing related high-performance micro- or nano-devices. [ABSTRACT FROM AUTHOR]

Introduction: Zinc oxide nanoparticles (ZnO-NPs) have garnered considerable interest in biomedical research primarily owing to their prospective therapeutic implications in combatting pathogenic diseases and microbial infections. The primary objective of this study was to examine the biosynthesis of zinc oxide nanowhiskers (ZnO-NWs) using chicken egg white (albumin) as a bio-template. Furthermore, this study aimed to explore the potential biomedical applications of ZnO NWs in the context of infectious diseases. Methods: The NWs synthesized through biological processes were observed using electron microscopy, which allowed for detailed examination of their characteristics. The results of these investigations indicated that the NWs exhibited a size distribution ranging from approximately 10 to 100 nm. Fouriertransform infrared spectroscopy (FTIR) and scanning electron microscopyenergy dispersive X-ray spectroscopy (SEM-EDX) mapping analyses successfully corroborated the size, dimensions, and presence of biological constituents during their formation. In this study, XTT assay and confocal imaging were employed to provide evidence of the efficacy of ZnO-NWs in the eradication of bacterial biofilms. The target bacterial strains were Staphylococcus aureus and Escherichia coli. Furthermore, we sought to address pertinent concerns regarding the biocompatibility of the ZnO-NWs. This was achieved through comprehensive evaluation of the absence of cytotoxicity in normal HEK-293T and erythrocytes. Results: The findings of this investigation unequivocally confirmed the biocompatibility of the ZnO-NWs. The biosynthesized ZnO-NWs demonstrated a noteworthy capacity to mitigate the dermatitis-induced consequences induced by Staphylococcus aureus in murine models after a therapeutic intervention lasting for one week. Discussion: This study presents a comprehensive examination of the biosynthesis of zinc oxide nanowhiskers (ZnO-NWs) derived from chicken egg whites. These findings highlight the considerable potential of biosynthesized ZnO-NWs as a viable option for the development of therapeutic agents targeting infectious diseases. The antibacterial efficacy of ZnO-NWs against both susceptible and antibiotic-resistant bacterial strains, as well as their ability to eradicate biofilms, suggests their promising role in combating infectious diseases. Furthermore, the confirmed biocompatibility of ZnO-NWs opens avenues for their safe use in biomedical applications. Overall, this research underscores the therapeutic promise of ZnO-NWs and their potential significance in future biomedical advancements. [ABSTRACT FROM AUTHOR]