Browsing by Subject "morphology"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
Item A Review of the Genus Serratella Edmunds, 1959 in China with Description of a New Species (Ephemeroptera: Ephemerellidae)(MDPI, 2022-11-04) Ding , Manqing; Jacobus, Luke M.; Zhou , Changfa; IUPUC Division of ScienceSpecies in the genus Serratella Edmunds, 1959 from China have never been compared and photographed systematically. Six valid Chinese Serratella species are recognized and revised in this paper. Among them, the imagos of S. brevicauda Jacobus et al., 2009 are unknown; the nymph of this species has a stout, strong body, with remarkably short caudal filaments and maxillary palpi. In contrast, only the imago stage of Serratella fusongensis (Su and You, 1988) (=Serratella longipennis Zhou et al., 1997, syn. nov.) is known; it has relatively long penes with small dorsal projections. The nymphs of S. setigera Bajkova, 1967 have small abdominal tergal spines but distinct, stout, blunt bristles on the spines, and the apexes of the male penes are round and shallowly divided. The fourth species, S. acutiformis sp. nov., which was collected from Western China, has sharp penial apexes (imagos) and large abdominal spines (nymphs). Unlike the former four species, S. ignita (Poda, 1761) and S. zapekinae Bajkova, 1967 has sub-quadrate penes without prominent dorsal projections. The nymph of S. ignita has lateral hair-like setae on the caudal filaments, while the nymph of S. zapekinae lacks such setae but has pairs of tubercles on the head and pronotum. Some characters used in the generic delineation of the genera Ephemerella Walsh, 1862 and Serratella, such as nymphal maxillary palpi and hair-like setae on caudal filaments as well as features of the imaginal penes and forelegs, are varied in Chinese species. However, all species in this paper have bifurcate ventral lamellae of gill VI. Our work highlights a need for further comparative systematic study of the genera Serratella, Ephemerella, and another related genus Torleya Lestage, 1917.Item Inhibition of cPLA2 has neuroprotective effects on motoneuron and muscle atrophy following spinal cord injury(Liebert, 2014) Liu, Nai-Kui; Byers, James S.; Lam, Tom; Lu, Qing-Bo; Sengelaub, Dale R.; Xu, Xiao-Ming; Department of Neurological Surgery, School of MedicineSurviving motoneurons undergo dendritic atrophy after spinal cord injury (SCI), suggesting an important therapeutic target for neuroprotective strategies to improve recovery of function after SCI. Our previous studies showed that phospholipase A2 (PLA2) may play an important role in the pathogenesis of SCI. In the present study, we investigated whether blocking cPLA2 pharmacologically with arachidonyl trifluoromethyl ketone (ATK) or genetically using cPLA2 knockout (KO) mice attenuates motoneuron atrophy following SCI. C57BL/6 mice received either sham or contusive SCI at the T10 level. At 30 min after SCI, mice were treated with ATK or vehicle. Four weeks later, motoneurons innervating the vastus lateralis muscle of the quadriceps were labeled with cholera toxin-conjugated horseradish peroxidase, and dendritic arbors were reconstructed in three dimensions. Soma volume, motoneuron number, lesion volume, and tissue sparing were also assessed, as were muscle weight, fiber cross-sectional area, and motor endplate size and density. ATK administration reduced percent lesion volume and increased percent volume of spared white matter compared to the vehicle-treated control animals. SCI with or without ATK treatment had no effect on the number or soma volume of quadriceps motoneurons. However, SCI resulted in a decrease in dendritic length of quadriceps motoneurons in untreated animals, and this decrease was completely prevented by treatment with ATK. Similarly, the vastus lateralis muscle weights of untreated SCI animals were smaller than those of sham-surgery controls, and these reductions were prevented by ATK treatment. No effects on fiber cross-sectional areas, motor endplate area or density were observed across treatment groups. Remarkably, genetically deleting cPLA2 in cPLA2 KO mice attenuated dendritic atrophy after SCI. These findings suggest that after SCI, cord tissue damage and regressive changes in motoneuron and muscle morphology can be reduced by inhibition of cPLA2, further supporting a role for cPLA2 as a neurotherapeutic target for SCI treatment.Item Overview of Nano-Fiber Mats Fabrication via Electrospinning and Morphology Analysis(MDPI, 2021) Ahmadian, Amirhossein; Shafiee, Abbas; Aliahmad, Nojan; Agarwal, Mangilal; Mechanical and Energy Engineering, School of Engineering and TechnologyElectrospun nano-fibers exhibit two significant properties: a high surface-to-volume ratio and a relatively defect-free molecular structure. Due to the high surface-to-volume ratio, electro-spun materials are well suited for activities requiring increased physical contact, such as providing a site for a chemical reaction or filtration of small-sized physical materials. However, electrospinning has many shortcomings, including difficulties in producing inorganic nanofibers and a limited number or variety of polymers used in the process. The fabrication of nanofiber bundles via electrospinning is explored in this analytical study and the relationship between all effective electrospinning parameters and the relative abundance of various fiber morphologies. Numerous variables could impact the fabrication of nanofibers, resulting in a variety of morphologies such as uniform, entangled, individual beads, beads-on-string, etc. Therefore, adequate ambient conditions and selecting the appropriate polymer and solvent for achieving a homogenous polymer solution and uniform with desired nanofiber properties for different applications of electro-spun materials are examined. Finally, the promising applications of nano-fine fibers in various fields achieved via electrospinning are studied in this paper.Item Recurrence rates of urinary calculi according to stone composition and morphology(Springer, 2018-10) Daudon, Michel; Jungers, Paul; Bazin, Dominique; Williams, James C., Jr.; Anatomy and Cell Biology, School of MedicineFew studies have examined the relative risk of recurrence of different stone types. The object of the present study was to evaluate the tendency for stone recurrence as a function of major mineral composition of the stones and morphological characteristics of the stones. This study was carried out using 38,274 stones for which we had data available to specify if the stone was from the first or a subsequent urinary stone episode. Stones were analyzed for morphology by stereomicroscope and for composition by infrared spectroscopy. Overall, 42.7% of stones were from patients who had had a previous stone event, with these being more frequent in men (44.4%) than in women (38.9%, p < 0.0001). Age of first stone occurrence was lowest for dihydroxyadenine (15.7 ± 16.6 years) and highest for anhydrous uric acid (62.5 ± 14.9 years), with the average age of first stones of calcium oxalate falling in the middle (40.7 ± 14.6 years for calcium oxalate dihydrate, and 48.4 ± 15.1 years for calcium oxalate monohydrate, COM). By composition alone, COM was among the least recurrent of stones, with only 38.0% of COM stones coming from patients who had had a previous episode; however, when the different morphological types of COM were considered, type Ic—which displays a light color, budding surface and unorganized section—had a significantly greater rate of recurrence, at 82.4% (p < 0.0001), than did other morphologies of COM. Similarly, for stones composed of apatite, morphological type IVa2—a unique form with cracks visible beneath a glossy surface—had a higher rate of recurrence than other apatite morphologies (78.8 vs. 39–42%, p < 0.0001). Stone mineral type alone is insufficient for identifying the potential of recurrence of the stones. Instead, the addition of stone morphology may allow the diagnosis of highly recurrent stones, even among common mineral types (e.g., COM) that in general are less recurrent.