Numerous Filaments Research Articles

Favorable outcome of Lasiodiplodia theobromae keratomycosis : a clinical case and systematic review

BackroudKeratitis caused by Lasiodiplodia theobromae is rare and typically associated with a poor prognosis. Current literature lacks sufficient evidence on effective management of patients with this condition.Case presentationA 74-year-old former agricultural worker presented with a red right eye, discomfort, and decreased visual acuity, progressing over three days without treatment. Examination revealed type 2 diabetes and a non-perforating, spiculated corneal abscess with a hypopyon in the right eye. Initial treatment included a triple antibiotic therapy and supportive care. Direct mycological examination identified numerous septate mycelial filaments. Antifungal treatment with natamycin and voriconazole, both topically and orally, was initiated. Cultures confirmed Lasiodiplodia theobromae. The patient showed significant improvement. Treatment continued for eight weeks, with a final visual acuity of 20/50 due to a stromal scar.ConclusionAn extensive literature review conducted in November 2023, using databases such as PubMed and Google Scholar with the keywords “lasiodiplodia” and “keratitis” yielded no previous cases of this specific condition being managed solely with the combined use of natamycin and voriconazole. This antifungal combination is commonly included in most management protocols for fungal keratitis. Factors such as the use of corticosteroids and delayed diagnosis were noted to adversely affect the prognosis. This case and this systematic review underscores the potential for non-surgical management options in severe fungal keratitis.

SDC-DeepLabv3+: Lightweight and Precise Localization Algorithm for Safflower-Harvesting Robots.

Harvesting robots had difficulty extracting filament phenotypes for small, numerous filaments, heavy cross-obscuration, and similar phenotypic characteristics with organs. Robots experience difficulty in localizing under near-colored backgrounds and fuzzy contour features. It cannot accurately harvest filaments for robots. Therefore, a method for detecting and locating filament picking points based on an improved DeepLabv3+ algorithm is proposed in this study. A lightweight network structure, ShuffletNetV2, was used to replace the backbone network Xception of the traditional DeepLabv3+. Convolutional branches for 3 different sampling rates were added to extract information on the safflower features under the receptive field. Convolutional block attention was incorporated into feature extraction at the coding and decoding layers to solve the interference problem of the near-color background in the feature-fusion process. Then, using the region of interest of the safflower branch obtained by the improved DeepLabv3+, an algorithm for filament picking-point localization was designed based on barycenter projection. The tests demonstrated that this method was capable of accurately localizing the filament. The mean pixel accuracy and mean intersection over union of the improved DeepLabv3+ were 95.84% and 96.87%, respectively. The detection rate and weights file size required were superior to those of other algorithms. In the localization test, the depth-measurement distance between the depth camera and target safflower filament was 450 to 510 mm, which minimized the visual-localization error. The average localization and picking success rates were 92.50% and 90.83%, respectively. The results show that the proposed localization method offers a viable approach for accurate harvesting localization.

Properties and characteristics of the nanosecond discharge developing at the water–air interface: tracking evolution from a diffused streamer to a spark filament

The characteristics of nanosecond discharge propagating along the water–air interface in a unique dielectric-barrier discharge (DBD)-like configuration with coplanar electrodes submerged in deionised (DI)/tap water are studied by combining ultrafast imaging and emission spectra with electrical characteristics. Time-resolved images provide a clear signature of streamer channels excited on the water surface at either side of the blade (insulated plastic separating the anode/cathode) and propagating perpendicularly away from it towards the anode/cathode with different velocities. Later on, the streamer channels convert into a few discrete and bright discharge channels due to ionisation instability (spark phase). There is no distinctive dependence on water conductivity in the streamer phase, as the optical emission spectroscopy and images of discharges only showed an increase of the luminosity and no significant changes in morphology. However, in the spark phase, more numerous, brighter, and thicker filaments form in tap water. The time-resolved emission spectra reveal the dominance of the first and second positive system of N2 molecular bands in the streamer phase, followed by the appearance of atomic lines of hydrogen, nitrogen, and oxygen in the spark phase. The emission spectra are utilised to estimate several important parameters (gas temperature, reduced electric field ( E/N ), and electron density ( ne )). The streamer phase is characterised by a low gas temperature and a peak E/N amplitude between 700 and 850 Td. On the other hand, the subsequent spark phase is characterised by a gas temperature of ∼400/1100 K and a free electron density up to ne∼1017 –1018 cm−3 in DI/tap water.

Association Between Biofilm Formation and Structure and Antibiotic Resistance in H. pylori.

Persistent infections caused by Helicobacter pylori (H. pylori), which are resistant to antibiotic treatment, pose a growing global public health concern. Biofilm formation is known to be associated with persistent infections due to its role in enhancing antimicrobial resistance and the tolerance of many pathogenic bacteria. This study aims to evaluate the biofilm formation of clinical isolates of H. pylori and its impact on antibiotic eradication. The thickness, morphology, and structure of biofilms derived from nine H. pylori strains were examined using confocal laser scanning microscopy, scanning electron microscopy, and transmission electron microscopy. Subsequently, the susceptibility of both planktonic and biofilm bacteria was assessed through the determination of minimum inhibitory concentration and minimum biofilm eradication concentration for amoxicillin, clarithromycin, levofloxacin, and tetracycline. The results revealed varying biofilm thicknesses and densities among the strains, characterised by the presence of numerous filaments intertwining and connecting bacterial cells. Additionally, several cases exhibited susceptibility based on MIC measurements but resistance according to MBEC measurements, with MBEC indicating a higher resistance rate. Pearson Correlation analysis demonstrated a positive correlation between biofilm thickness and MBEC results (0 < r < 1), notably significant for amoxicillin (r = 0.801, P = 0.009) and tetracycline (r = 0.696, P = 0.037). Different strains of H. pylori exhibit variations in their capacity to release outer membrane vesicles (OMVs) and form biofilms. Biofilm formation can influence the effectiveness of amoxicillin and tetracycline in eradicating susceptible bacterial strains.

Empirical testing of cryoconite granulation: Role of cyanobacteria in the formation of key biogenic structure darkening glaciers in polar regions.

Cryoconite, the dark sediment on the surface of glaciers, often aggregates into oval or irregular granules serving as biogeochemical factories. They reduce a glacier's albedo, act as biodiversity hotspots by supporting aerobic and anaerobic microbial communities, constitute one of the organic matter (OM) sources on glaciers, and are a feeder for micrometazoans. Although cryoconite granules have multiple roles on glaciers, their formation is poorly understood. Cyanobacteria are ubiquitous and abundant engineers of cryoconite hole ecosystems. This study tested whether cyanobacteria may be responsible for cryoconite granulation as a sole biotic element. Incubation of Greenlandic, Svalbard, and Scandinavian cyanobacteria in different nutrient availabilities and substrata for growth (distilled water alone and water with quartz powder, furnaced cryoconite without OM, or powdered rocks from glacial catchment) revealed that cyanobacteria bind mineral particles into granules. The structures formed in the experiment resembled those commonly observed in natural cryoconite holes: they contained numerous cyanobacterial filaments protruding from aggregated mineral particles. Moreover, all examined strains were confirmed to produce extracellular polymeric substances (EPS), which suggests that cryoconite granulation is most likely due to EPS secretion by gliding cyanobacteria. In the presence of water as the only substrate for growth, cyanobacteria formed mostly carpet-like mats. Our data empirically prove that EPS-producing oscillatorialean cyanobacteria isolated from the diverse community of cryoconite microorganisms can form granules from mineral substrate and that the presence of the mineral substrate increases the probability of the formation of these important and complex biogeochemical microstructures on glaciers.

The Accretion Mode in Sub-Eddington Supermassive Black Holes: Getting into the Central Parsecs of Andromeda

The inner kiloparsec regions surrounding sub-Eddington (luminosity less than 10−3 in Eddington units, L Edd) supermassive black holes (BHs) often show a characteristic network of dust filaments that terminate in a nuclear spiral in the central parsecs. Here we study the role and fate of these filaments in one of the least accreting BHs known, M31 (10−7 L Edd) using hydrodynamical simulations. The evolution of a streamer of gas particles moving under the barred potential of M31 is followed from kiloparsec distance to the central parsecs. After an exploratory study of initial conditions, a compelling fit to the observed dust/ionized gas morphologies and line-of-sight velocities in the inner hundreds of parsecs is produced. After several million years of streamer evolution, during which friction, thermal dissipation, and self-collisions have taken place, the gas settles into a disk tens of parsecs wide. This is fed by numerous filaments that arise from an outer circumnuclear ring and spiral toward the center. The final configuration is tightly constrained by a critical input mass in the streamer of several 103 M ☉ (at an injection rate of 10−4 ); values above or below this lead to filament fragmentation or dispersion respectively, which are not observed. The creation of a hot gas atmosphere in the region of ∼106 K is key to the development of a nuclear spiral during the simulation. The final inflow rate at 1 pc from the center is ∼1.7 × 10−7 M ☉ yr−1, consistent with the quiescent state of the M31 BH.

Controlling diffusion dynamics with electrode engineering for stable and reliable resistive switching in AlN/Ag-based CBRAM

Due to high scalability, quick operating speed, wide dynamic on–off resistance range, and analog current switching, cation migration-based conductive bridge random access memory (CBRAM) has received much attention for a wide range of applications including data storage, logic gates, and neuromorphic circuits. However, Inadequate controllability of metal-ion injection and the creation of numerous filaments are the major issues for the switching stability. In this work, we investigated Ag/Ta/Ag stacked electrode structure to improve cycle-to-cycle and device-to-device switching uniformity by controlling the Ag-ion diffusion into the host material. The device shows stable dc endurance for 100 switching cycles without much degradation. The data retention behavior for 104 s is observed in the stacked electrode device at room temperature as well as an elevated temperature of 80 °C. The proposed device emulates biological synaptic functionality by demonstrating long-term potentiation(LTP) and depression (LTD) behavior for 10 epochs.

Supernova-remnant origin of the Galactic-Centre filaments

ABSTRACT The mechanism to produce the numerous Galactic-Centre filaments (GCFs) that vertically penetrate the Galactic plane without clear evidence of connection to the disc remains a mystery. Here, we show that the GCFs are explained by relics of supernova remnants (rSNRs) driven by hundreds of supernovae (SNe) that exploded in the star-forming ring of the central molecular zone at an SN rate of ∼2 × 10−4 yr−1 in the past ∼0.5 Myr. The evolution of rSNRs is simulated by the propagation of fast-mode magnetohydrodynamic waves, which are shown to converge around the Galactic rotation axis by the focusing effect. Tangential projection of the cylindrical wavefronts on the sky constitutes the vertical filaments. The SNR model explains not only the morphology, but also the non-thermal radio spectrum, smoothed brightness over the distribution area consistent with the Σ–D relation of SNR, and the heating mechanism of hot plasma. We discuss the implication of the SNR model on the study of the interstellar physics in the Galactic Centre and star-formation activity.

A new red alga from Japan, Dasya japonovillosa sp. nov. (Delesseriaceae, Ceramiales)

SummaryA new red alga from Japan, Dasya japonovillosa, is described. This new species and D. enomotoi, both of which have elongated axes densely covered with numerous soft monosiphonous filaments, may have been misidentified as D. villosa by previous investigators in Japan. Dasya villosa differs from D. japonovillosa and D. enomotoi in the distinct five pericentral cells in transverse sections and palisade‐like tetrasporangial cover cells. The new species is distinguished from several similar species by the combination of the following: an elongated axis (to 65 cm), subdichotomously divided axes and polysiphonous branches, indistinct pericentral cells in transverse sections except near the apices, and the presence of enlarged, inner cortical cells, radially arranged numerous soft monosiphonous filaments, three‐celled carpogonial branches, four tetrasporangia in each fertile segment of the stichidia, and one (rarely two) tetrasporangial cover cell that is not elongated longitudinally and rarely divided transversely.

Wake Flow of Dandelion Pappus

There are two kinds of seeds that fly by wind, pappose seeds and winged seeds. The former is known to make parachuting flights, which utilize the drag force acting on the pappus. Each flying seed is designed to have a small rate of descent and to float in the air current as long as possible, according to their environmental conditions. The common dandelion is a classic example of a wind-dispersed plant and facilitates flight by the pappus, which is composed of numerous filaments and gaps. The spatial structures in high porosity pappus are presumed to the key to drag enhancement and long-distance dispersal. In the present study, in order to investigate the relationship between the spatial characteristics of pappus with high porosity and flow behavior around the pappus, smoke flow visualization was performed by changing the porosity of the pappus. The drag coefficient decreases with increasing the porosity of the pappus. However, even if the same porosity, the aerodynamic characteristics were changed by the spatial structure of the pappus.

The first finding of aegagropilious, or algal balls, in the oldest freshwater Lake Baikal

Abstract. Free-floating algal aggregations, or aegagropilious, are a rare phenomenon known from some freshwater or marine environments worldwide. In September 2014, unusual green algal balls were washed ashore in Ludar Bay on the west coast of the northern basin of Lake Baikal. The paper describes these algal aggregations and characterizes their composition. The Baikal algal balls mainly consisted of green filamentous algae of the family Cladophoraceae, such as Cladophora glomerata, Rhizoclonium sp., and Chaetomorpha sp. Other prominent components of the balls were numerous filaments of Spirogyra and Oedogonium. These taxa are known for their rapid growth in response to nutrients increase. As the result of the hyperproduction of filamentous benthic algae in the coastal zone of Lake Baikal, new living forms such as aegagropilious-like aggregations have been occurring. The algal balls signify the adaptive capacities of the Lake Baikal algal communities and might retain their functioning in the natural ecosystem s self-purification processes.

Origin, branching pattern, foraminal and intraspinal distribution of the human lumbar sinuvertebral nerves

BACKGROUND CONTEXTThe lumbar sinuvertebral nerve (SVN) innervates the outer posterior intervertebral disc (IVD); it is thought to mediate discogenic low-back pain (LBP). Controversy, however, exists on its origins at higher (L1–L2) versus lower (L3–L5) lumbar levels. Additionally, lack of knowledge regarding its foraminal and intraspinal branching patterns and extensions may lead to iatrogenic damage. PURPOSETo systematically describe the origins of the L2 and L5 SVNs, their morphological variation in the intervertebral foramen (IVF) and intraspinal distribution. STUDY DESIGNDissection-based study of 20 SVNs with histological confirmation in five embalmed human cadavers. METHODSThe origin, branching pattern and distribution of the L2 and L5 SVNs was investigated bilaterally in five human cadavers using dorsal and anterolateral dissection approaches. Parameters studied included somatic and/or autonomic SVN root contributions, foraminal SVN morphology and course, diameter, branching point, intraspinal distribution and IVD innervation pattern. Nerve tissue was confirmed by immunostaining for neurofilament and S100 proteins. RESULTSThe SVN and its origins was identified in all except one IVF at L2 and in all foramina at L5. At L2, the SVN arose in nearly 90% of sides from both somatic and autonomic roots and at L5 in 40% of sides. The remaining SVNs were formed by purely autonomic roots. The SVN arose from significantly more roots at L2 than L5 (3.1 ± 0.3 vs. 1.9 ± 0.3, respectively; p=.022). Four different SVN morphologies could be discerned in the L2 IVF: single filament (22%), multiple (parallel or diverging) filament (33%), immediate splitting (22%) and plexiform (22%) types, whereas the L5 SVN consisted of single (90%) and multiple (10%) filament types. SVN filaments were significantly thicker at L2 than L5 (0.48 ± 0.06 mm vs. 0.33 ± 0.02 mm, respectively; p=.043). Ascending SVN filaments coursed roughly parallel to the exiting spinal nerve root trajectory at L2 and L5. Branching of the SVN into ascending and descending branches occurred mostly intraspinal both at L2 and L5. Spinal canal distribution was also similar for L2 and L5 SVNs. Lumbar posterior IVDs were innervated by the descending branch of the parent SVN and ascending branch of the subjacent SVN. CONCLUSIONSThe SVN at L2 originates from both somatic and autonomic roots in 90% of cases and at L5 in 40% of cases. The remaining SVNs are purely autonomic. In the IVF, the L2 SVN is morphologically heterogeneous, but generally consists of numerous filaments, whereas at L5 90% contains a single SVN filament. The L2 SVN is formed by more roots and is thicker than the L5 SVN. Intraspinal SVN distribution is confined to its level of origin; lumbar posterior IVDs are innervated by corresponding and subjacent SVNs (ie, two spinal levels). CLINICAL SIGNIFICANCEOur findings indicate that L5 discogenic LBP may be mediated both segmentally and nonsegmentally in 40% of cases and nonsegmentally in 60% of cases. Failure of lower lumbar discogenic pain treatment may be the result of only interrupting the nonsegmental pathway, but not the segmental one as well. Relating SVN anatomy to microsurgical spinal approaches may prevent iatrogenic damage to the SVN and the formation of postsurgical back pain.

Comparative morphology of the spermatophores and spermatozoa of three Amazon freshwater crabs (Decapoda, Brachyura, Trichodactylidae)

ABSTRACT The ultrastructure of spermatophores and spermatozoa of freshwater crabs are little known, and a description of characters unique to this taxon is lacking. In this study, we describe and compare the ultrastructure of spermatophores and spermatozoa of Dilocarcinus pagei, Zilchiopsis oronensis and Valdivia serrata. In addition, we perform a comparative analysis with other freshwater crab species described in the literature. All species studied presented predominantly coenospermic spermatophores, in addition Z. oronensis and V. serrata also presented some cleistospermic spermatophores; which are described here for the first time in Trichodactylidae. The spermatozoa of the three species share a pattern found in the Brachyura, however, we found common traits for Trichodactylidae. The operculum is thick, protruding and imperforate with the presence of a prominent subopercular ring. The shape of the operculum is roundish in D. pagei and more triangular in Z. oronensis and V. serrata. The perforatorial chamber is panduriform in D. pagei and Z. oronensis, and oblong in V. serrata. The membrane of the perforatorial chamber in D. pagei has numerous shallow corrugations and short perforatorial filaments, while Z. oronensis and V. serrata have fewer, almost indistinguishable corrugations and long perforatorial filaments. All three species have a marked lateral expansion of the base of the perforatorial chamber and overall truncation of the acrosome vesicle, in Z. oronensis and V. serrata, absence of an acrosome ray zone, developed thickened ring and a thick nucleo-cytoplasmic plate, being obviously lamellar in D. pagei and homogeneous in Z. oronensis and V. serrata. The spermatozoa presents similar characteristics between Trichodactylidae and other freshwater crab families opening the possibility of unit all heterotreme freshwater crab families as a single group. The probably Trichodactylidae autapomorphies, that diverges from all other freshwater crabs, reinforce the hypothesis that the trichodactylids derived later as an independent lineage of freshwater crabs.

Update on fungal keratitis in France: a case-control study.

To report an epidemiological update of documented fungal keratitis (FK) in a French tertiary ophthalmological centre from 2014 to 2018 in comparison with a previous period from 1993 to 2008. Sixty-two consecutive FK documented by microbiological corneal scrapings were compared with the 64 FK of the previous study. Amphotericin B and voriconazole eye drops were administered hourly. Population characteristics, clinical findings, aetiological organisms and treatments were analysed. The most frequently identified fungi were Fusarium (61%), Aspergillus (6.5%) and Candida (5%). Thirty out of 44 cases examined with invivo confocal microscopy (IVCM) presented filaments. Ten required conventional cross-linking, 9 therapeutic penetrating keratoplasty, and 2 enucleation. Risk factors significantly associated with the absence of response to medical treatment were patient age (p = 0.01), presence of a deep stromal infiltrate at presentation (p = 0.04) and high numbers of filaments in IVCM images (p = 0.01). The two populations were comparable in age, but not in sex ratio males/females (18/44 versus 37/26 in the previous study; p = 0.001). The frequency of contact lens-associated infection increased from 35.5% to 71% (p = 0.0001) between the two periods. Since then, filamentous FK increased from 69% (44/64) to 95% (59/62) (p = 0.0001). A history of keratoplasty was less frequently reported during the last period (3.2% (2/62) versus 17% (11/64) of cases (p = 0.01)). A clear decrease in the frequency of therapeutic keratoplasty was noted from 39% (25/64) to 14% (9/62) (p = 0.02). The frequency of filamentous keratomycosis is currently increasing. Elderly patients and the presence of numerous filaments in IVCM are associated with poor clinical outcomes.

Formation of the Hub–Filament System G33.92+0.11: Local Interplay between Gravity, Velocity, and Magnetic Field

Abstract The formation of filaments in molecular clouds is an important process in star formation. Hub–filament systems (HFSs) are a transition stage connecting parsec-scale filaments and protoclusters. Understanding the origin of HFSs is crucial to reveal how star formation proceeds from clouds to cores. Here we report James Clerk Maxwell telescope POL-2 850 μm polarization and IRAM 30 m C18O (2–1) line observations toward the massive HFS G33.92+0.11. The 850 μm continuum map reveals four major filaments converging to the center of G33.92+0.11 with numerous short filaments connecting to the major filaments at local intensity peaks. We estimate the local orientations of filaments, magnetic field, gravity, and velocity gradients from observations, and we examine their correlations based on their local properties. In the high-density areas, our analysis shows that the filaments tend to align with the magnetic field and local gravity. In the low-density areas, we find that the local velocity gradients tend to be perpendicular to both the magnetic field and local gravity, although the filaments still tend to align with local gravity. A global virial analysis suggests that the gravitational energy overall dominates the magnetic and kinematic energy. Combining local and global aspects, we conclude that the formation of G33.92+0.11 is predominantly driven by gravity, dragging and aligning the major filaments and magnetic field on the way to the inner dense center. Traced by local velocity gradients in the outer diffuse areas, ambient gas might be accreted onto the major filaments directly or via the short filaments.

Increased number of activated microglia in rat spinal cord during early stage of diabetic induction.

Diabetic neuropathy is a common chronic complication in diabetes mellitus. Such neuropathy associates with chronic inflammation and immune system activation. Microglia, a type of neuroglia, are involved in the immune system and are found in grey and white matter of the central nervous system, such as the brain and spinal cord. The spinal cord connects the peripheral nervous system and the higher brain centre. Hyperglycaemia during diabetes mellitus has been found to activate and increase number of microglia in the dorsal grey horn or column of the lumbar segments in spinal cord, which release several cytokines in the development of hypersensitivity in diabetic neuropathic pain. Therefore, in this study, anatomical alterations of rat spinal microglia in all areas (dorsal, intermediate and ventral columns of grey matter and dorsal, lateral and ventral funiculi of white matter) in cervical enlargement, thoracic level and lumbosacral enlargement were observed in early stage of diabetic conditions by using light and transmission electron microscopies. The numbers of microglia in all parts of grey and white matter of all spinal levels significantly increased in the diabetic group. The structures and ultrastructures of microglia in grey and white matter at cervical enlargement, thoracic level and lumbosacral enlargement similarly changed in diabetes. In diabetic rats, microglia became hypertrophied with a pale nucleus. Moreover, short fragments of rough endoplasmic reticulum, elevated numbers of lysosomes and numerous actin filaments in the cytoplasm were examined. Microglial phagocytosis of myelin and axonal debris were also observed. In this investigation, the morphology of spinal microglia during short-term diabetes became activated during hyperglycaemia. It is suggested that these changes may be involved in the development of diabetic neuropathic pain in the spinal cord.

The effect of end-plate wetting and unpinned contact lines on the filament thinning of strain hardening fluids

The Filament Extension Atomizer™ (FEA) is a unique technology designed for highly viscous or strain-hardening fluids that are otherwise difficult to atomize. The fluid is processed as a thin film between the contact points of two counter-rotating rollers of different materials. As the film is processed beyond the contact point, it is subject to an extensional flow that creates numerous thin filaments. As the filaments are stretched, they thin, and eventually, surface tension causes them to break into tightly dispersed droplets. Certain fluids, particularly those of low to moderate viscosity and high surface tension, can present challenges to atomize in FEA. Due to the tendency of these fluids to coalesce, their wetting on the rollers has been critical in optimizing film formation, though the impact of surface wetting on filament formation and breakup is not well understood. Accordingly, we studied the role of end-plate wetting for a high surface tension, aqueous, strain-hardening polymer solution on filament formation, thinning, and breakup, and fluid transfer to the end-plates, using a modified Capillary Breakup Extensional Rheometer (CABER). We found that filament formation and evolution were dramatically affected by both the wetting and wetting imbalances between the two end-plates, leading to different behavior across different end-plate combinations. The highly imbalanced wetting scenarios (i.e., combining a highly wetting and a non-wetting end-plate) gave rise to the most extreme deviations from classic behavior in conventional CABER experiments, such as long persisting filaments.

High‐Tensile Strength, Composite Bijels through Microfluidic Twisting

AbstractRope making is a millennia old technique to collectively assemble numerous weak filaments into flexible and high tensile strength bundles. However, delicate soft matter fibers lack the robustness to be twisted into bundles by means of mechanical rope making tools. Here, weak microfibers with tensile strengths of a few kilopascals are combined into ropes via microfluidic twisting. This is demonstrated for recently introduced fibers made of bicontinuous interfacially jammed emulsion gels (bijels). Bijels show promising applications in use as membranes, microreactors, energy and healthcare materials, but their low tensile strength make reinforcement strategies imperative. Hydrodynamic twisting allows to produce continuous bijel fiber bundles of controllable architecture. Modelling the fluid flow field reveals the bundle geometry dependence on a subtle force balance composed of rotational and translational shear stresses. Moreover, combining multiple bijel fibers of different compositions enables the introduction of polymeric support fibers to raise the tensile strength to tens of megapascals, while simultaneously preserving the liquid like properties of the bijel fibers for transport applications. Hydrodynamic twisting shows potentials to enable the combination of a wide range of materials resulting in composites with features greater than the sum of their parts.

Discovery and Characterization of Thermoproteus Spherical Piliferous Virus 1: a Spherical Archaeal Virus Decorated with Unusual Filaments.

We describe the discovery of an archaeal virus, one that infects archaea, tentatively named Thermoproteus spherical piliferous virus 1 (TSPV1), which was purified from a Thermoproteales host isolated from a hot spring in Yellowstone National Park (USA). TSPV1 packages an 18.65-kb linear double-stranded DNA (dsDNA) genome with 31 open reading frames (ORFs), whose predicted gene products show little homology to proteins with known functions. A comparison of virus particle morphologies and gene content demonstrates that TSPV1 is a new member of the Globuloviridae family of archaeal viruses. However, unlike other Globuloviridae members, TSPV1 has numerous highly unusual filaments decorating its surface, which can extend hundreds of nanometers from the virion. To our knowledge, similar filaments have not been observed in any other archaeal virus. The filaments are remarkably stable, remaining intact across a broad range of temperature and pH values, and they are resistant to chemical denaturation and proteolysis. A major component of the filaments is a glycosylated 35-kDa TSPV1 protein (TSPV1 GP24). The filament protein lacks detectable homology to structurally or functionally characterized proteins. We propose, given the low host cell densities of hot spring environments, that the TSPV1 filaments serve to increase the probability of virus attachment and entry into host cells.IMPORTANCE High-temperature environments have proven to be an important source for the discovery of new archaeal viruses with unusual particle morphologies and gene content. Our isolation of Thermoproteus spherical piliferous virus 1 (TSPV1), with numerous filaments extending from the virion surface, expands our understanding of viral diversity and provides new insight into viral replication in high-temperature environments.

Microscopic Anatomy of the Gill and Lung of the Apple Snail Pomacea maculata, with Notes on the Volume of the Lung

The anatomy of the gills of aquatic gastropods has not been extensively studied, and in particular, there are few recent studies that contain ultramicroscopic images. Similarly, the literature on the anatomy of the lungs of air-breathing terrestrial snails is not voluminous. Apple snails of the genus Pomacea possess both a gill and a fully functional lung. The lung is used to breathe air and as a flotation device. This study reports on the anatomy of the gill, lung, and pneumostome of the invasive species Pomacea maculata. The gill has a structure similar to that reported in other gastropods. The gill is monopectinate and consists of numerous triangular filaments. Ciliary tracts populate the distal portions of the filaments. The filaments are primarily connective tissue, interspersed with abundant muscle bands and hemolymph sinuses. The lung is a large ovoid sac; the floor is attached to the foot of the snail and the roof of the lung underlies the mantle epithelium. The lung tissue layers consist of connective tissue and smooth muscle bundles, and hemolymph spaces are present in both the floor and roof. Cells that contain calcium granules are very abundant in the lung tissue. Patches of cilia adorn the epithelium adjacent to the central airspace. The pneumostome is a muscular structure and is heavily ciliated. The lung volume of a 50-g animal is about 6 mL. The results of this study add to the knowledge of the anatomy of respiratory organs in molluscs and show that the lung is a major site of storage of calcium.