Experimental acoustic modal analysis of a tenor saxophone.

This paper presents an application of the Experimental Acoustic Modal Analysis (AMA) on a vintage 10 M Conn tenor saxophone. This technique originates from the traditional Modal Analysis which is commonly adopted to determine the dynamic behaviour of solid structures. The methodology is based on the measurement of Frequency Response Functions (FRFs) as a ratio of the acoustic pressure, measured by means of a set of microphones positioned along the saxophone body, and the volume velocity produced by an acoustic source and measured at the instrument input. The microphones are housed on the stripped saxophone keys by means of tailored three-dimensional printed adapters. The AMA makes use of the FRFs to extract modal parameters, such as resonance frequencies, loss factors, and mode shapes. These parameters pertain to the cavity modes of the saxophone passive resonator. The analysis has been performed for three different notes (B ♭, B, and C) and for two registers of the instrument in order to show the potential of the technique. Moreover, the influence of the mouthpiece volume on the cavity modes has been shown. The information obtained by AMA can find useful application in the validation of analytical or numerical models of this kind of musical instruments.

Functional and radiological outcomes after bridging therapy versus direct thrombectomy in stroke patients with unknown onset: Bridging therapy versus direct thrombectomy in unknown onset stroke patients with 10-point ASPECTS.

BACKGROUND AND PURPOSE: The aim was to assess functional and radiological outcomes after bridging therapy (intravenous thrombolysis plus mechanical thrombectomy) versus direct mechanical thrombectomy (MT) in unknown onset stroke patients. METHODS: A cohort study was conducted on prospectively collected data from unknown onset stroke patients who received endovascular procedures at ≤6 h from symptom recognition or awakening time. RESULTS: Of the 349 patients with a 10-point Alberta Stroke Program Early Computed Tomography Score (ASPECTS), 248 received bridging and 101 received direct MT. Of the 134 patients with 6-9-point ASPECTS, 123 received bridging and 111 received direct MT. Each patient treated with bridging was propensity score matched with a patient treated with direct MT for age, sex, study period, pre-stroke disability, stroke severity, type of stroke onset, symptom recognition to groin time (or awakening to groin time), ASPECTS and procedure time. In the two matched groups with 10-point ASPECTS (n = 73 vs. n = 73), bridging was associated with higher rates of excellent outcome (46.6% vs. 28.8%; odds ratio 2.302, 95% confidence interval 1.010-5.244) and successful recanalization (83.6% vs. 63%; odds ratio 3.028, 95% confidence interval 1.369-6.693) compared with direct MT; no significant association was found between bridging and direct MT with regard to rate of symptomatic intracerebral hemorrhage (0% vs. 1.4%). In the two matched groups with 6-9-point ASPECTS (n = 45 vs. n = 45), no significant associations were found between bridging and direct MT with regard to rates of excellent functional outcome (44.4% vs. 31.1%), successful recanalization (73.3% vs. 76.5%) and symptomatic intracerebral hemorrhage (0% vs. 0%). CONCLUSIONS: Bridging at ≤ 6 h of symptom recognition or awakening time was associated with better functional and radiological outcomes in unknown onset stroke patients with 10-point ASPECTS.

Karyometry and quantitative immunohistochemical analysis of the urothelium in tissue sections: a feasibility study based on chromatin remodeler DAXX immunostaining.

The aim of this study was to investigate the feasibility of applying a software traditionally used in the field of engineering to pathology, in particular to tissue sections from normal urothelium (NU) immuno-stained for the chromatin remodeler DAXX (death domain-associated protein). The study included 5 cases of NU. Images were recorded with a Nikon digital camera. The nuclear area and the intensity of nuclear staining were analyzed with a software package developed in LabVIEW environment. The nuclear size is 14.8 plus or minus 6.5 square microns. The nuclei in the cells adjacent to the stroma are slightly smaller than in the intermediate cells by a factor of 0.86. The mean nuclear area of the nuclei in the superficial cell layer in NU is identical to the nuclei in the intermediate cell layers. For each nucleus intensity of nuclear staining is calculated based on the gray value of the individual picture elements in the green color plane. The mean and standard deviation of nuclear gray value are 106 plus or minus 15. The mean value in the nuclei adjacent to the stroma is slightly greater by a factor 1.02 and 1.04 compared to the intermediate and superficial cell layers. In conclusion, this exploratory study shows that karyometry and quantitative immunohistochemical analysis can be done accurately by using a digital camera commonly available to pathologists and an image analysis software routinely used in the field of engineering.

Agent-based station for on-line diagnostics by self-adaptive laser Doppler vibrometry.

A self-adaptive diagnostic system based on laser vibrometry is proposed for quality control of mechanical defects by vibration testing; it is developed for appliances at the end of an assembly line, but its characteristics are generally suited for testing most types of electromechanical products. It consists of a laser Doppler vibrometer, equipped with scanning mirrors and a camera, which implements self-adaptive bahaviour for optimizing the measurement. The system is conceived as a Quality Control Agent (QCA) and it is part of a Multi Agent System that supervises all the production line. The QCA behaviour is defined so to minimize measurement uncertainty during the on-line tests and to compensate target mis-positioning under guidance of a vision system. Best measurement conditions are reached by maximizing the amplitude of the optical Doppler beat signal (signal quality) and consequently minimize uncertainty. In this paper, the optimization strategy for measurement enhancement achieved by the down-hill algorithm (Nelder-Mead algorithm) and its effect on signal quality improvement is discussed. Tests on a washing machine in controlled operating conditions allow to evaluate the efficacy of the method; significant reduction of noise on vibration velocity spectra is observed. Results from on-line tests are presented, which demonstrate the potential of the system for industrial quality control.

Population-based pace study: lifetime and past-year prevalence of headache in adults.

Primary headache prevalence in the adult Italian general population has been little studied so far. This is an observational, cross-sectional, population-based study conducted in a subject sample that was representative of the city of Parma's general population >or=age 18. The lifetime prevalence of headache was 69.1%, i.e. 75.8% in women and 60.6% in men; the past-year prevalence of headache was 42.8%, i.e. 52.0% in women and 31.1% in men. Most people suffer from one headache subtype. Headache past-year prevalence decreases with age, both in men and in women. After 60, the likelihood of suffering from headache is low. In more than 80% of cases, headache starts before age 40 and, therefore, it is not very likely for people to develop headache at an advanced age (>50 years). This is the first population-based study conducted in Italy on a sample aged >or=18 since the publication of the IHS diagnostic criteria in 1988.

Population-based pace study: headache frequency and disease perception in adult subjects with headache.

Headache is a disorder that has a very negative personal and social impact. This is an observational, cross-sectional, population-based study conducted in a subject sample (n = 904) that was representative of the town of Parma's general population aged 18 and over. The aim of this study, which is a part of a larger project, was to assess the frequency of headache and the disease perception of subjects with headache during the past year (n = 387). The average number of headache days in the past year was 34.9 days and it was comparable in men and in women: 49.9% of subjects had 1-12 days of headache in the past year, 34.9% had 1-52 days, 11.9% had 53-180 days, and 3.4% had more than 180 days. Only three subjects had headache every day during the past year. Only one-third of the subjects with headache in the past year considered themselves headache sufferers. The analysis by gender showed differences between men and women: although the average number of headache days in the past year was comparable in the male and female populations, women considered their headache a disease more often than men did. In addition, the percentage of men who considered their headache a disease did not increase with the increase in the number of headache days in the past year. More in-depth studies on this important aspect are needed.

Confidential enquiry into avoidable vehicle accident deaths in the province of Modena, Italy.

The authors describe the methods and results of a kind of study confidential enquiries into avoidable deaths very rarely performed in the Mediterranean area. After assessing some quali/ quantitative evaluation criteria, an independent expert panel investigated the quality of each step in emergency health care. Information was collected by clinical and forensic reports (clinical method). Of 102 cases, 4 were avoidable deaths and 18 probably avoidable. These results, which are comparable with other similar ones found in Italy (autoptic method) and abroad, have been useful in highlighting some health care errors: in particular, in on-site care and in emergency department diagnosis and treatment. Other avoidable factors emerging were the inappropriateness of transporting severe trauma cases to a small hospital lacking proper equipment and trained staff, and the importance of staff training in first emergency care of severe trauma on ambulance. This situation had been highlighted previously and led to implementation of trauma centres. The methods implemented turned out to be quite statistically reproducible and have been used in local health care planning, especially in the rearrangement of ambulance deployment and emergency staff training.

Teeth mobility measurement: a laser vibrometry approach.

OBJECTIVE: This work presents a new technique based on the assessment of the mobility degree through the application of dynamic loads and the measurement of the tooth displacement with a laser Doppler vibrometer. SUMMARY BACKGROUND DATA: Measurements of the mobility degree have been made, up to now, by the application of static loads and the measurement of the consequent displacement. The results obtained with the measurement technique proposed by Muhlemann (1967) have been validated by O'Leary et al. (1964) and by Persson and Sweson (1980). This approach, however, has not been clinically disseminated both because of the high cost of the equipment and, above all, because of the difficulty in performing the measurements. METHODS: The ratio between the maximum of the tooth displacement and the input force peak has been considered as the mobility degree index. Dynamic loads have been applied and measured on teeth, with a small hammer and a load cell. The consequent displacement of tooth has been measured with a Laser Doppler vibrometer that allows easy to use and versatile noncontact measurements with high accuracy and sensitivity (< 0.1 mm/sec). RESULTS: An introductory in vitro study has been carried out on real teeth extracted and mounted on structures with different-stiffness silicone cast (stiffness of the support is one of the parameters responsible for teeth mobility), in order to evaluate the technique. An in vivo study has also been carried out on different teeth of a healthy patient. It is possible to observe the agreement between the O'Leary results and ones obtained in this work. The practicality of the procedure has also been demonstrated. CONCLUSIONS: Good correspondence between data available in literature and results obtained has been demonstrated. The use of the technique here proposed could allow having a deeper knowledge of the behavior of the periodontal teeth system: the tooth mobility under dynamic loads. With this new technique, it will be possible to quickly measure a pathological mobility of the tooth, before it becomes evident and problematic.