CROSSwind stability of road vehicles under thunderSTORMs: CFD aerodynamic characterization and experimental validation of DrivAer and Small Lorry models

LAUREA MAGISTRALEGli effetti del vento trasversale rappresentano una sfida importante per la stabilità e la sicurezza dei veicoli, soprattutto in presenza di raffiche intense come quelle generate dai temporali. Prevedere con precisione le forze aerodinamiche in queste condizioni è fondamentale per migliorare il design dei veicoli e adottare misure di sicurezza più efficaci. In questo contesto si inserisce la presente tesi, sviluppata nell’ambito del progetto PRIN CROSS-STORM, che si propone di elaborare metodologie per valutare il rischio di instabilità dei veicoli in condizioni meteorologiche simili a quelle dei temporali. Il lavoro si concentra sull’analisi aerodinamica di due modelli rappresentativi di veicoli stradali: una vettura DrivAer dal profilo aerodinamico e un modello più squadrato, denominato Small Lorry. Sono state effettuate simulazioni CFD considerando un ampio intervallo di angoli di imbardata (0–180°) per ricreare scenari critici di vento trasversale. Il comportamento aerodinamico di entrambi i modelli in scala è stato quindi studiato e validato con dati sperimentali raccolti in galleria del vento. Le simulazioni sono state condotte con un approccio RANS stazionario, integrato da un algoritmo automatico basato su superfici Non- Conformal Coupled, che consente di ridurre sia i tempi di calcolo che l’intervento manuale. Infine, è stata svolta un’analisi approfondita del campo di flusso ottenuto con la CFD, con l’obiettivo di comprendere meglio come i principali fattori che influenzano il flusso aerodinamico impattino sul comportamento complessivo del veicolo in condizioni di vento trasversale estremo, contribuendo così a una conoscenza più completa dell’aerodinamica dei veicoli esposti a venti generati dai temporali.Crosswind effects pose a significant challenge to vehicle stability and safety, especially under strong lateral gusts such as those generated by thunderstorms. Accurately predicting aerodynamic forces in such conditions is essential for improving vehicle design and implementing effective safety measures. Within this context, the present thesis—developed as part of the PRIN project CROSS-STORM, which aims to develop methodologies for assessing the risk of vehicle instability under thunderstorm-like conditions—focuses on the aerodynamic response of two representative road vehicles: a streamlined DrivAer passenger car model and a more squared Small Lorry model. Firstly, CFD simulations were conducted across a full range of yaw angles (0–180°) to replicate critical crosswind scenarios. The aerodynamic behaviour of both scaled models was analysed and validated against experimental data obtained through wind tunnel testing. The simulations adopt a steady-state RANS approach, combined with a Non-Conformal Coupled surface automation algorithm designed to reduce both computational time and the need for user intervention. Finally, a detailed CFD-based flow analysis was carried out to improve the understanding of aerodynamic behaviour under severe crosswind, investigating how key flow-affecting parameters influence the flow field, thereby contributing to a more comprehensive understanding of vehicle aerodynamics in thunderstorm-induced wind conditions

Larval performance and adult attraction of Delia platura (Diptera: Anthomyiidae) in a native and an introduced crop

Delia platura Meigen is an important pest in crops around the world. Its host range includes almost 50 species and it can develop in soil organic matter. In Ecuador, D. platura is a serious problem for the crop, Lupinus mutabilis Sweet (Chocho) and it also attacks broccoli (Brassica oleracea). After broccoli is harvested, crop residue is mixed with soil or collected and stored close to Chocho fields. The objectives of this study were to determine the adaptive responses of larvae reared on different hosts and whether D. platura females are preferentially attracted to germinating L. mutabilis seeds or broccoli residue. Accordingly, larval performance and attraction of female D. platura reared on broccoli residue and L. mutabilis seeds were evaluated. The number of larvae, pupae and adults were higher when reared on broccoli. Conversely, pupal weight was higher and time from larva to pupa, pupa to adult and total life cycle were longer in flies reared on L. mutabilis. Although D. platura developed more quickly on broccoli, L. mutabilis was also a good host since pupae were heavier compared with flies reared on broccoli. Delia platura females reared on broccoli preferred broccoli residue to L. mutabilis in an olfactometer. Volatiles from broccoli residue in soil may attract D. platura females and stimulate oviposition on L. mutabilis seeds. Environmentally benign production of L. mutabilis crops with minimal insecticide applications may require the elimination of fresh broccoli residue as fertilizer in soils where L. mutabilis is cultivated

Cost effect of uniquely designed component choices of over the product life of a workstation

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997, and Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management, 1997.Includes bibliographical references (p. 83).by Anne Paige Di Censo.M.B.A.M.S

Does the Diffusion Profile Differ Between Botulinum Toxin Type a Formulations? Implications for the Management of Post-Stroke Spasticity

Botulinum toxin type A is a first-line treatment for post-stroke spasticity, with selective action at nerve endings and minimal effects beyond the injection site. However, concerns about potential adverse reactions due to toxin diffusion and spread can significantly influence physicians' therapeutic decisions in managing post-stroke spasticity. Current evidence shows that while the main formulations of botulinum toxin type A have different molecular weights and sizes, they do not exhibit differing diffusion profiles. Instead, the key factors determining botulinum toxin type A diffusion and spread in post-stroke spasticity management are the dose (i.e., the actual amount of 150 kDa neurotoxin protein injected), dilution, and injection volume. Other injection-related factors, such as the needle gauge and injection speed, have also been suggested to have a secondary influence on botulinum toxin type A diffusion and spread. The needs of patients with post-stroke spasticity may vary, and depending on treatment goals, botulinum toxin type A diffusion and spread can be something to avoid or may offer therapeutic benefits by reaching a greater number of nerve terminals in the target muscle, enhancing the toxin's effect. These factors should be carefully evaluated in spasticity clinics

Characterization of a Novel Packaged Hydrogel Wound Dressing by 2.35 T Magnetic Resonance Imaging

Hydrogel wound dressing makes easier the treatment of patients suffering from difficult wounds. A new process for the manufacturing of a sterile, packaged hydrogel wound dressing, based on an interpenetrating structure of calcium alginate, agar, and polyvinylpyrrolidone, was recently developed. The new formulation overtakes some previous technologies’ drawbacks expressing a better resistance to mechanical deformations compared to products on the market. In this work, the 2.35 T proton density, spin-lattice relaxation time, spin-spin relaxation time, phase-coherence relaxation, and water apparent diffusion coefficient analysis in the new hydrogel and several alternative formulations, including a commercial one (Neoheal®), are reported. Specifically, the combination of agar, acting as a thermolabile forming agent, with calcium alginate and γ irradiated polyvinylpyrrolidone, acting, respectively, as physical, and chemical crosslinking agents with an irreversible (temperature independent) effect, have been investigated. The new hydrogel formulation brings a qualitative improvement in its handling due to its increased mechanical stiffness when compared to the commercial hydrogel reference. This comes together with a reduced water content (100 vs. 112 for proton density in arbitrary units) and swelling capacity (88% vs. 124%) but with improved water mobility (1.42 vs. 1.34 × 10−3 mm2 s−1 for the apparent diffusion coefficient)

Management of spastic equinovarus foot in children with cerebral palsy: an evaluation of anatomical landmarks for selective nerve blocks of the tibial nerve motor branches

Objective: To define the anatomical landmarks of tibial motor nerve branches for selective motor nerve blocks of the gastrocnemii,  soleus and tibialis posterior muscles in the management of spastic equinovarus foot. Design: Observational study. Patients: Twenty-four children with cerebral palsy with spastic equinovarus foot. Methods: Considering the affected leg length, motor nerve branches to the gastrocnemii, soleus and tibialis posterior muscles were tracked using ultrasonography, and located in the space (vertical, horizontal, deep) according to the position of fibular head (proximal/distal) and a virtual line from the middle of popliteal fossa to the Achilles tendon insertion (medial/lateral). Results: Location of motor branches was defined as percentage of the affected leg length. Mean coordinates were: for the gastrocnemius medialis 2.5 ± 1.2% vertical (proximal), 1.0 ± 0.7% horizontal (medial), 1.5 ± 0.4% deep; for the gastrocnemius lateralis 2.3 ± 1.4% vertical (proximal), 1.1 ± 0.9% horizontal (lateral), 1.6 ± 0.4% deep; for the soleus 2.1 ± 0.9% vertical (distal), 0.9 ± 0.7% horizontal (lateral), 2.2 ± 0.6% deep; for the tibialis posterior 2.6 ± 1.2% vertical (distal), 1.3 ± 1.1% horizontal (lateral), 3.0 ± 0.7% deep. Conclusion: These findings may help the identification of tibial motor nerve branches to perform selective nerve blocks in patients with cerebral palsy with spastic equinovarus foot

Is the outcome of diagnostic nerve block related to spastic muscle echo intensity? A retrospective observational study on patients with spastic equinovarus foot

Objective: To investigate the relationship between spastic calf muscles echo intensity and outcome of tibial nerve motor branches selective block in patients with spastic equinovarus foot. Design: Retrospective observational study. Patients: Forty-eight patients with spastic equinovarus foot. Methods: Each patient was given selective, diagnostic nerve block (lidocaine 2% perineural injection) of the tibial nerve motor branches. All patients were evaluated before and after block. Outcomes: spastic calf muscles echo intensity measured with the Heckmatt scale; affected ankle dorsiflexion passive range of motion; calf muscles spasticity measured with the modified Ashworth scale and the Tardieu scale (grade and angle). Results:  As to the outcome of tibial nerve selective diagnostic block (difference between pre- and post-block condition), the Spearman correlation showed a significant inverse association of the spastic calf muscles echo intensity with the affected ankle dorsiflexion passive range of motion (P=0.045

Effects of pulsed electromagnetic fields on bone fractures: a systematic review update

iNtroductioN: fractures are common bone injuries, which have a great burden on global health. fracture healing is a long-term process that may be influenced by a number of factors. The 10-15% of all bone fractures may be complicated by an impaired healing (i.e. delayed union or non-union). The application of weak electromagnetic fields has been proposed to have different effects on bones such as enhancing proliferation – orientation – migration of osteoblast-like cells and supporting osteogenic differentiation in bone marrow-derived mesenchymal stem cells. Despite the amount of evidence on cellular and histological effects, to date the application of pulsed electromagnetic fields has not achieved univocal consensus in daily practice. the purpose of this systematic review update is to research, select, analyze and summarize the most recent scientific evidence regarding the effects of pulsed electromagnetic fields in the treatment of acute bone fractures. EVidENcE acQuisitioN: a systematic review using the following Mesh terms (Magnetic field therapy; Electromagnetic fields; bone and bones; fractures, bone; fractures healing) and strings {(“Magnetic field therapy [mh]” or “Electromagnetic fields [mh]) or “magnetotherapy” OR “pulsed electromagnetic field”) and (“Fractures, bone [mh]” OR “Bone and Bones [mh]”) and (“Fractures Healing [mh]”)} was conducted on pubMed, cochrane library, Epistemonikos and scopus electronic databases. only full articles published in English between January 2014 and December 2022 were considered. Eligibility criteria were defined according to the Population, Intervention, Comparison, outcomes, and study (picos) design framework. case reports, case series, uncontrolled studies and expert opinions were excluded. all articles were checked for quality and risk of bias. EVIDENCE SYNTHESIS: Three randomized controlled trials were included (197 patients in total). None of the studies found significant effects of pulsed electromagnetic fields on the acute bone healing process. Contradictory results about pain relief emerged. Only one study showed a transitory positive effect of pulsed electromagnetic fields on strength and range of motion recovery in patients with acute bone fracture. CONCLUSIONS: This systematic review update does not support the use of pulsed electromagnetic fields for improving the bone healing process in patients with acute fractures. Controversial evidence was found about the effects of pulsed electromagnetic fields on pain and functional recovery. considering the scant and heterogenous literature published to date, which represents a limit for our conclusion, further studies with rigorous and high-quality methodology are needed

The Basal Ganglia: More than just a switching device

Summary The basal ganglia consist of a variety of subcortical nuclei engaged in motor control and executive functions, such as motor learning, behavioral control, and emotion. The striatum, a major basal ganglia component, is particularly useful for cognitive planning of purposive motor acts owing to its structural features and the neuronal circuitry established with the cerebral cortex. Recent data indicate emergent functions played by the striatum. Indeed, cortico-striatal circuits carrying motor information are paralleled by circuits originating from associative and limbic territories, which are functionally integrated in the striatum. Functional integration between brain areas is achieved through patterns of coherent activity. Coherence belonging to cortico- basal ganglia circuits is also present in Parkinson’s disease patients. Excessive synchronization occurring in this pathology is reduced by dopaminergic therapies. The mechanisms through which the dopaminergic effects may be addressed are the object of several ongoing investigations. Overall, the bulk of data reported in recent years has provided new vistas concerning basal ganglia role in the organization and control of movement and behavior, both in physiological and pathological conditions. In this review, basal ganglia functions involved in the organization of main movement categories and behaviors are critically discussed. Comparatively, the multiplicity of Parkinson’s disease symptomatology is also revised

Is the Silfverskiöld Test a valid tool for evaluating calf muscles spastic overactivity in patients with stroke? A retrospective observational study

Background: Spastic equinus (plantar flexed) foot is a common postural pattern in patients who suffer from post-stroke spasticity. To date, some clinicians use the Silfverskiöld Test in their practice to differentiate between gastrocnemius and soleus muscle overactivity in patients with spastic equinus (plantar flexed) foot. This use of the Silfverskiöld Test goes beyond its original aim, which was to distinguish isolated gastrocnemius contracture in patients with equinus deformity. Aim: The aim of this study was to investigate the Silfverskiöld Test validity for evaluating spastic equinus (plantar flexed) foot (i.e., differentiation between gastrocnemius and soleus muscle overactivity) by checking its outcome against those of selective diagnostic nerve block of tibial motor nerve branches to the soleus, gastrocnemius and tibialis posterior muscles. Design: The design of the study was retrospective observational. Setting: The study was set in a university hospital. Population: Sixty-seven adult stroke patients with spastic equinus (plantar flexed) foot. Methods: Each patient underwent selective diagnostic nerve block of tibial motor nerve branches to the soleus, gastrocnemius and tibialis posterior muscles. All patients were evaluated before diagnostic nerve block by means of the Silfverskiöld Test which was considered positive when ankle joint passive dorsiflexion was greater with the knee flexed than extended. Furthermore, they were assessed before and after nerve block by means of the modified Ashworth Scale and the Tardieu Scale. Results: Our sample included 41 males and 26 females (mean age 57.6 years) suffering from spastic equinus (plantar flexed) foot due to chronic stroke (mean time from onset 2.4 years). Forty-eight patients out of 67 presented with positive Silfverskiöld Test. The χ2 test showed no association between the Silfverskiöld Test and spastic overactivity of the gastrocnemius (P=0.253), soleus (P=0.605) and tibialis posterior (P=0.462) muscles as evaluated by serial selective diagnostic block of the tibial nerve motor branches. Conclusions: Our findings do not support the Silfverskiöld Test as a valid tool for evaluating spastic equinus (plantar flexed) foot to differentiate between gastrocnemius, soleus and tibialis posterior spastic muscle overactivity in adult patients with stroke. Clinical rehabilitation impact: The choice for an appropriate management of spastic equinus (plantar flexed) foot in adults with stroke should not be mainly defined on the base of Silfverskiöld Test