Effects of yawed inflow on the aerodynamic and aeroacoustic performance of ducted wind turbines

Ducted Wind Turbines (DWTs) can be used for energy harvesting in urban areas where non-uniform inflows might be the cause of aerodynamic and acoustic performance degradation. For this reason, an aerodynamic and aero-acoustic analysis of DWTs in yawed inflow condition is performed for two duct geometries: a baseline commercial DWT model, DonQi®, and one with a duct having a higher cross-section camber with respect to the baseline, named DonQi D5. The latter has been obtained from a previous optimization study. A numerical investigation using Lattice-Boltzmann Very-Large-Eddy Simulations is presented. Data confirm that the aerodynamic performance improvement, i.e. increase of the power coefficient, is proportional to the increase of the duct thrust force coefficient. It is found that, placing the DWT at a yaw angle of 7.5 , the aerodynamic performances of the DonQi D5 DWT model are less affected by the yaw angle. On the other hand, this configuration shows an increase of broadband noise with respect to the baseline DonQi® one, both in non-yawed and yawed inflow conditions. This is associated to turbulent boundary layer trailing edge noise due to the turbulent flow structures developing along the surface of the duct

The Ampullae of the Inner Ear in the Lizard Podarcis S. Sicula. Ultrastructural Aspects

The inner ear ampullae of the lizard Podarcis s. sicula were studied to determine better the ultrastructure of ampullar epithelial cells. Our study confirmed that the ampullae of the membranous labyrinth of this lizard are similar to those of other vertebrates in their ultrastructural aspect. Moreover, our observations revealed a special type of dark cells, restricted to a small area of the crista. They appeared similar to type II sensory cells and showed a dark, finely granular cytoplasm, containing numerous mitochondria and ribosomes, extensive Golgi apparatus and abundant glycogen. The morphology of these cells suggests that they may be special sensory cells, or different stages of sensory cells, probably implied in the crista cell turn-over described for some vertebrate groups

Morphogenesis of otoliths during larval development in brook lamprey, Lampetra planeri

Otolith morphogenesis of the brook lamprey, Lampetra planeri, was analysed from larval to adult stages. The brook lamprey remains juvenile for about 4 years, facilitating analysis of otoliths maturation that permits to identify relevant evolutionary traits in this primitive species and to compare our results with more evoluted species of vertebrate taxa. We combined histochemical, immunohistochemical, scanning electron microscopy, elemental analysis and X-ray diffraction of lamprey otoliths to establish possible relationships between otolithic mass, individual crystals, the otolithic organic substance that binds individual otoconia together and the inorganic elements that mineralize the lamprey otoliths. Histochemical analysis of the otoliths suggests that mineralization occurs gradually, beginning near the apex of the secretory epithelium. Then, the otoconia increase in size by deposition of layers of a dense crystalline substance. Immunohistochemical reactivity of calcium binding proteins indicates that calmodulin, calbindin, S-100 and parvalbumin are parts of the uncalcified organic mass that holds otoconia together. Imaging of the immunoreactivity of each protein by Confocal Laser Scanning Microscopy in ammocoete at the first year of the larval stage shows weak reaction products which, however, gradually increase in intensity, with peak value in ammocoete at the fourth year of the larval stage

Airway Remodeling in Feline Lungs

Airway remodeling encompass structural changes that occur as the result of chronic injury and lead to persistently altered airway structure and function. Although this process is known in several human respiratory conditions such as asthma and chronic obstructive pulmonary disease (COPD), airway remodeling is poorly characterized in the feline counterpart. In this study, we describe the spontaneous pulmonary changes in 3 cats paralleling the airway remodeling reported in humans. We observed airway smooth muscle cells (ASMCs) hyperplasia (peribronchial and interstitial), airway subepithelial and interstitial fibrosis, and vascular remodeling by increased number of vessels in the bronchial submucosa. The hyperplastic ASMCs co-expressed α-SMA, vimentin and desmin suggesting that vimentin, which is not normally expressed by ASMCs, may play a role in airway thickening, and remodeling. ASMCs had strong cytoplasmic expression of TGFβ-1, which is known to contribute to tissue remodeling in asthma and in various bronchial and interstitial lung diseases, suggesting its involvement in the pathogenesis of ASMCs hyperplasia. Our findings provide histologic evidence of airway remodeling in cats. Further studies on larger caseloads are needed to support our conclusions on the value of this feline condition as an animal model for nonspecific airway remodeling in humans

Definition of a benchmark for low Reynolds number propeller aeroacoustics

Experimental and numerical results of a propeller of 0.3 m diameter operated at 5000 RPM and axial velocity ranging from 0 to 20 m/s and advance ratio ranging from 0 to 0.8 are presented as a preliminary step towards the definition of a benchmark configuration for low Reynolds number propeller aeroacoustics. The corresponding rotational tip Mach number is 0.23 and the Reynolds number based on the blade sectional chord and flow velocity varies from about 46000 to 106000 in the operational domain and in the 30% to 100% blade radial range. Force and noise measurements carried out in a low-speed semi-anechoic wind-tunnel are compared to scale-resolved CFD and low-fidelity numerical predictions. Results identify the experimental and numerical challenges of the benchmark and the relevance of fundamental research questions related to transition and other low Reynolds number effects

Towards the definition of a benchmark for low Reynolds number propeller aeroacoustics

Experimental and numerical results of a propeller of 0.3 m diameter operated in quiescent standard ambient conditions at 5000 RPM and axial velocity ranging from 0 to 20 m/s and advance ratio ranging from 0 to 0.8 are presented as a preliminary step towards the definition of a benchmark configuration for low Reynolds number propeller aeroacoustics. The corresponding rotational tip Mach number is 0.231 and the Reynolds number based on the blade sectional chord and flow velocity in the whole radial and operational domain ranges from about 54000 to 106000. Force and noise measurements carried out in a low-speed semi-anechoic windtunnel are compared with scale-resolved CFD and low-fidelity numerical results. Results identify the experimental and numerical challenges of the benchmark and the relevance of fundamental research questions related to transition and other low Reynolds number effects

Assembly of the Auditory Circuitry by a Hox Genetic Network in the Mouse Brainstem

Rhombomeres (r) contribute to brainstem auditory nuclei during development. Hox genes are determinants of rhombomere-derived fate and neuronal connectivity. Little is known about the contribution of individual rhombomeres and their associated Hox codes to auditory sensorimotor circuitry. Here, we show that r4 contributes to functionally linked sensory and motor components, including the ventral nucleus of lateral lemniscus, posterior ventral cochlear nuclei (VCN), and motor olivocochlear neurons. Assembly of the r4-derived auditory components is involved in sound perception and depends on regulatory interactions between Hoxb1 and Hoxb2. Indeed, in Hoxb1 and Hoxb2 mutant mice the transmission of low-level auditory stimuli is lost, resulting in hearing impairments. On the other hand, Hoxa2 regulates the Rig1 axon guidance receptor and controls contralateral projections from the anterior VCN to the medial nucleus of the trapezoid body, a circuit involved in sound localization. Thus, individual rhombomeres and their associated Hox codes control the assembly of distinct functionally segregated sub-circuits in the developing auditory brainstem

Passive transfer status and growth performance in newborn buffalo calves allowed to nurse the dam

The objective of this study was to evaluate the effect of passive transfer status, determined by measuring serum IgG concentration 24 hours after parturition, on growth performance in buffalo calves fed milk replacer or allowed to nurse the dam during the first month of life. Experiment consisted of 24 healthy buffalo calves from birth to 30 days old. Significant quadratic associations were detected between serum IgG concentration 24 hours after birth and day-30 weight (P < 0.05; R2 = 0.62) and between serum IgG concentration 24 hours after birth and the mean daily gain from birth to day 30 (P < 0.01; R2 = 0.74) in buffalo calves allowed to nurse the dam. No significant association was detected between serum IgG concentration 24 hours after birth and measures of growth performance in buffalo calves fed milk replacer. Results indicated that passive transfer status, determined as serum IgG concentration 24 hours after birth, was a significant source of variation in growth performance when buffalo calves nursed the dam. Maximizing passive transfer of immunity by allowing buffalo calves to nurse the dam increased the growth performance during the first month of life

Canine smooth muscle tumors: A clinicopathological study

Canine smooth muscle tumors (SMTs) commonly develop in the alimentary and female genital tracts and less frequently in soft tissue. The definition of histological criteria of malignancy is less detailed for SMTs in dogs than in humans. This study evaluated the clinicopathologic features of canine SMTs and compared the veterinary and human medical criteria of malignancy. A total of 105 canine SMTs were evaluated histologically and classified according to both veterinary and human criteria. The Ki67 labeling index was assessed in all SMTs. Estrogen receptor (ER) and progesterone receptor (PR) expression was evaluated for soft tissue SMTs. Follow-up data were available in 25 cases. SMTs were diagnosed in the female genital tract (42%), alimentary tract (22%), and soft tissue (20%). Soft tissue SMTs frequently arose in the perigenital area, pelvic cavity, and retroperitoneum. A subset of soft tissue SMTs expressed ER and/or PR, resembling the gynecologic type of soft tissue SMT in humans. SMTs were less frequently malignant when assessed with human criteria than with veterinary criteria, better reflecting their benign behavior, especially in the genital tract where human criteria tolerate a higher mitotic count for leiomyoma. Decreased differentiation was correlated with increased proliferation, necrosis, and reduced desmin expression. Mitotic count, Ki67 labeling index, and necrosis were correlated with metastases and tumor-related death. Further prognostic studies are warranted to confirm the better performance of the human criteria when assessing SMT malignancy, especially genital cases, to confirm their usefulness in ER/PR-expressing soft tissue SMTs, and to better define the most useful prognostic parameters for canine SMTs

Dupilumab ocular side effects in patients with atopic dermatitis: a systematic review

Atopic dermatitis (AD) is a chronic, inflammatory skin disorder that most frequently occurs in children, but it can also affect adults. Even though most AD cases can be managed with topical treatments, moderate-to-severe forms require systemic therapies. Dupilumab is the first human monoclonal antibody approved for the treatment of AD. Its action is through IL-4 receptor alpha subunit inhibition, thus blocking IL-4 and IL-13 signaling pathways. It has been shown to be an effective, well-tolerated therapy for AD, as well as for asthma, chronic rhinosinusitis with nasal polyposis (CRSwNP), and eosinophilic esophagitis (EoE). However, an increasing incidence of dupilumab-induced ocular surface disease (DIOSD) has been reported in patients treated with dupilumab, as compared to placebo. The aim of this study was to summarize scientific data regarding DIOSD in AD patients treated with dupilumab. A search of PubMed and clinicaltrials.gov databases was performed. There was no limit to study design. All AD cases were moderate-to-severe. DIOSD was either dermatologist-, allergist-, or ophthalmologist-assessed. Evidence shows that DIOSD occurs most frequently in patients with atopic dermatitis and not in other skin conditions, neither in patients with asthma, CRSwNP, nor EoE who are on dupilumab treatment. Further studies are warranted in order to establish a causal relationship between dupilumab and ocular surface disease. Nevertheless, ophthalmological evaluations prior to dupilumab initiation can benefit AD patients with previous ocular pathology or current ocular symptomatology. Also, patch testing for ocular allergic contact dermatitis might be advantageous in patients with a history of allergic conjunctivitis. Furthermore, TARC, IgE, and circulating eosinophils levels might be important biomarkers for a baseline assessment of future candidates to dupilumab treatment. However, TARC measurements should be resumed for research purposes only