Design and experimental validation of a finite-size labyrinthine metamaterial for vibro-acoustics: enabling upscaling towards large-scale structures.

In this article, we present the design and experimental validation of a labyrinthine metamaterial for vibro-acoustic applications. Based on a two-dimensional unit cell, different designs of finite-size metamaterial specimens in a sandwich configuration including two plates are proposed. The design phase includes an optimization based on Bloch-Floquet analysis with the aims of maximizing the band gap and extruding the specimens in the third dimension while keeping the absorption properties almost unaffected. By manufacturing and experimentally testing finite-sized specimens, we assess their capacity to mitigate vibrations in vibro-impact tests. The experiments confirm a band gap in the low- to mid-frequency range. Numerical models are employed to validate the experiments and to examine additional vibro-acoustic load cases. The metamaterial's performances are compared with benchmark solutions, usually employed for noise and vibration mitigation, showing a comparable efficacy in the band gap region. To eventually improve the metamaterial's performance, we optimize its interaction with the air and test different types of connections between the metamaterial and the homogeneous plates. This finally leads to metamaterial samples largely exceeding the benchmark performances in the band gap region and reveals the potential of interfaces for performance optimization of composed structures.This article is part of the theme issue 'Current developments in elastic and acoustic metamaterials science (Part 1)'.

Cross-sectional imaging and laparoscopic findings of diaphragmatic mesothelial cysts.

AIM: To present cross-sectional imaging, surgical findings, and follow-up results of diaphragmatic mesothelial cysts. MATERIALS AND METHODS: Radiological findings for location, size, shape, and internal structure of cysts were reviewed retrospectively. For patients that underwent surgery, surgical reports and laparoscopy images were reviewed. In conservatively managed patients, changes in size and imaging findings of the cyst were assessed during follow-up visits. RESULTS: A total of 13 paediatric cases with an imaging and/or pathological diagnosis of diaphragmatic mesothelial cyst were identified. In all cases, the cystic lesions were located between the diaphragm and the posterolateral aspect of the right lobe of the liver. Eleven lesions (84.6%) had a bi-lobulate shape. Eight of these cases underwent laparoscopic cyst aspiration/unroofing. The postoperative course was uneventful and there were no cases of recurrence. The remaining five cases were managed conservatively with follow-up available in four cases. In three cases (75%), there was reduction in the size of the cysts with a mean volume reduction of 55%. CONCLUSION: Diaphragmatic mesothelial cysts are congenital cystic lesions that are usually detected incidentally. A common pitfall is incorrect interpretation of the lesion as a hepatic cyst. Conservative management with imaging follow-up can be adopted in asymptomatic cases with typical imaging findings.

Investigation of biological effects of some Mannich Bases containing Bis-1,2,4- Triazole.

In this study, the effects of Mannich bases containing bis-1,2,4-triazole on the levels of in vivo malondialdehyde (MDA) and antioxidant vitamins (A, E, C) were examined in serum, livers and kidneys of rats. DA and vitamin (A, E, C) levels were determined by high performance liquid chromatography (HPLC). Antioxidant effect was investigated by determining the MDA levels in Saccharomyces cerevisiae cells as in vitro. Furthermore, the antitumor effects of compounds were investigated against MCF-7 human breast cancer cells. Interrelations of results among control and compound groups were evaluated using SPSS statistical software package. As a result, some of the compounds showed effective biological activity when compared to control conditions. The test compounds used in this study may be effective for utilization in the selection and design of model compounds for further studies.

Alopecia areata in Turkey: demographic and clinical features.

BACKGROUND: Alopecia areata is a complex genetic disease with still many unknown aspects, and many studies have been tried to find some clues about it. OBJECTIVE: We aimed to investigate the demographic and clinical characteristics of alopecia areata in Turkish patients. METHODS: Demographic data, localization, attack number in addition to some parameters such as disease duration, severity, age of onset, family history and ophiasis pattern were evaluated in 539 alopecia areata patients. RESULTS: The male to female ratio was 1.6:1. Occipital and beard-moustache areas were mostly affected. Positive family history was noticed in 24.1% of the patients. The age of onset was earlier in women than in men (P = 0.04). Severe forms showed more persistent (> or = 1 year) disease duration (P = 0.00). Ophiasis was more common in severe, long duration (> or = 1 year) and early onset (< or = 18 years) disease (P = 0.00 for all parameters). Childhood alopecia areata (< or = 18 years) was also associated with long duration of the disease (P = 0.016) and positive family history (P = 0.008) when compared with adult onset (> 18 years) alopecia areata.

Evaluation of Diffusion-weighted MR Imaging as a Technique for Detecting Bone Marrow Edema in Patients with Osteitis Pubis.

PURPOSE: Our aims were to determine the feasibility of diffusion-weighted magnetic resonance imaging (DWI) in the detection of bone marrow edema (BME) and explore the apparent diffusion coefficient (ADC) alterations in patients with osteitis pubis (OP). MATERIALS AND METHODS: 42 consecutive patients clinically suspected to have athletic pubalgia and 31 control subjects were enrolled in the study. All subjects underwent diagnostic focused magnetic resonance imaging (MRI) and DWI at b values of 0 and 600 s/mm2. Two radiologists reviewed the images for the presence of active OP. The presence of subchondral BME and contrast enhancement were considered to indicate active OP. ADC values were measured from public bodies of both groups. DWI results were correlated with routine MRI findings. Receiver-operating-characteristic curves were formed. Cut-off values for ADC, sensitivity and specificity values were measured. RESULTS: 36/42 (85%) of the cases had BME/enhancement on routine MRIs and identified as active OP. ADC measurements of the patients were greater than the controls (P < 0.05). For the optimal cut-off values DWI showed sensitivity and specificity values of 97.3%, and 90.3%, for the right, and 97.1%, and 96.7% for the left side, respectively (Area under the curve 0.965 and 0.973). Intra-and inter-rater reliability for readers were substantial-perfect for all sessions. CONCLUSION: DWI is fast, accurate, and highly reproducible technique for the detection of BME in patients with active OP. It allows distinct bone marrow contrast without the use of gadolinium contrast, increases visual perception of active lesions, gives objective information by quantifying the diffusion coefficients, thus increase diagnostic confidence. We suggest the use of DWI as a cost-effective adjunctive tool for the diagnosis of active OP particularly in early cases and inconclusive diagnostic MRI. Future studies are necessary to determine the utility of DWI to evaluate severity of the disease and treatment response before returning athletes to play.

Can sarcoidosis cause autoamputation of a finger phalanx?

Sarcoidosis is a multisystemic granulomatous disease. In the case presented, autoamputation of the distal phalanx of a little finger of the left hand was observed. The possibility of autodigital amputation as a result of sarcoidosis is discussed.

Bilateral multiple piloleiomyomas on the breast.

Piloleiomyomas are benign smooth muscle tumors arising from the erector pilorum muscles in the skin. They vary in size and number, and are often spontaneously painful or sensitive to touch and cold. In this paper, we present two young female patients who have multiple breast piloleiomyoma and discuss the related findings.

Measurement of epidermal thickness in a patient with psoriasis by computer-supported image analysis.

The aim of the present study was to measure full epidermal thickness, stratum corneum thickness, rete length, dermal papilla widening and suprapapillary epidermal thickness in psoriasis patients using a light microscope and computer-supported image analysis. The data obtained were analyzed in terms of patient age, type of psoriasis, total body surface area involvement, scalp and nail involvement, duration of psoriasis, and family history of the disease. The study was conducted on 64 patients and 57 controls whose skin biopsies were examined by light microscopy. The acquired microscopic images were transferred to a computer and measurements were made using image analysis. The skin biopsies, taken from different body areas, were examined for different parameters such as epidermal, corneal and suprapapillary epidermal thickness. The most prominent increase in thickness was detected in the palmar region. Corneal thickness was more pronounced in patients with scalp involvement than in patients without scalp involvement (t=-2.651, P=0.008). The most prominent increase in rete length was observed in the knees (median: 491 microm, t=10.117, P=0.000). The difference in rete length between patients with a positive and a negative family history was significant (t=-3.334, P=0.03), being 27% greater in psoriasis patients without a family history. The differences in dermal papilla distances among patients were very small. We conclude that microscope-supported thickness measurements provide objective results.

Subepidermal calcified nodule.

Subepidermal calcified nodules are rarely seen and are classified under idiopathic subepidermal calcifications. They commonly affect children. It is most frequently encountered in the face, and it is less common in the extremities. Here, we present a case where the lesion was localized on the knees of a 23-year-old female patient.

Prophylactic accessory-pathway ablation in asymptomatic patients with a Wolff-Parkinson-White electrocardiographic pattern.

OBJECTIVES: The optimal approach is controversial in asymptomatic patients who are coincidentally found to have evidence of an accessory pathway (AP) on an ECG. The risk of sudden cardiac death (SCD) is low, and the risk of developing symptoms also appears to be low, although a wide range of incidences have been reported. In our trial, we tested the hypothesis that if prophylactic accessory-pathway ablation performed at the time of the initial electrophysiological testing would improve the long-term outcome in asymptomatic patients with a Wolff-Parkinson-White electrocardiographic pattern. PATIENTS AND METHODS: Recruitment of patients began on February 1, 2004, and ended on February 5, 2009. All 110 asymptomatic patients were hospitalized and underwent electrophysiological testing the same day to assess the inducibility of atrioventricular reciprocating tachycardia. The anterograde effective refractory period of the accessory pathway was defined as the longest coupling interval at which anterograde block in the bypass tract was observed. For the statistical analysis, the statistical software SPSS version 15.0 for Windows (SPSS Inc., Chicago, IL, USA). RESULTS: Of 110 asymptomatic patients with a Wolff-Parkinson-White electrocardiographic pattern, 80 patients were ablated. Ablation group consisted of these patients. Control group consisted of remaining 30 and were divided into two groups according to the anterograde effective refractory period of the accessory pathway. There was no significant difference between three groups in terms of arrhythmic events (p: 0.58). CONCLUSIONS: Asymptomatic patients with the Wolff-Parkinson-White syndrome do not require prophylactic ablation, since they remain asymptomatic for many years.

A case of melanonychia due to Candida albicans.

Candida species rarely cause black pigmentation of infected nails and only a few cases have been reported in the literature. We describe a 53-year-old white man who had diffuse melanonychia of the fourth right fingernail due to C. albicans. A progressive dark pigmentation of his nail appeared over 6 months, following paronychial inflammation. The melanonychia was associated with brittleness. There was no onycholysis or hyperkeratosis. Direct examination with potassium hydroxide demonstrated round yeast cells in the specimen. The samples were cultured on Sabouraud glucose agar containing chloramphenicol at 27 degrees C and showed white growth after a few days. The patient was successfully treated with systemic itraconazole.

Prevalence of oral lesions in 13- to 16-year-old students in Duzce, Turkey.

OBJECTIVE: The aim of this study was to determine the prevalence of oral lesions in 13- to 16-year-old students. METHODS: A cross-sectional survey was carried out on students in Duzce, a province in the western Black Sea region of Turkey. A total of 993 children aged between 13 and 16 from eight secondary schools were examined. Oral lesions with recurrent behavior, if observed, were recorded at the time of examination. Venous blood samples were obtained for detecting hemoglobin levels. RESULTS: Two hundred sixty adolescents (26.2%) were diagnosed with at least one oral mucosal lesion at the time of the examination. Thirteen different mucosal alterations were diagnosed, and the most common lesions were angular cheilitis (9%), linea alba (5.3%), and aphthous ulceration (3.6%). The correlation between occurrence of mucosal lesions and sex was not statistically significant (P > 0.05). Statistical evaluation of the data revealed a significant relationship only between the presence of angular cheilitis and anemia (P < 0.05). CONCLUSION: This study is the first epidemiologic study of oral mucosal lesions in adolescents in Turkey. Angular cheilitis was the only oral mucosal lesion that had a significant correlation with anemia.

Persistent serpentine supravenous hyperpigmented eruption associated with docetaxel.

Various mucocutaneous reactions have been reported with the use of systemic docetaxel. We describe a 47-year-old man who developed a persistent serpentine supravenous hyperpigmented eruption (PSSHE), beginning at the site of docetaxel injection and spreading along the superficial venous network in the anterior aspect of the right forearm and distal arm. The eruption occurred after the first infusion of docetaxel following insufficient venous washing. A second infusion was administered through a vein in the other forearm, but this time, abundant venous washing was performed and a similar eruption did not occur. To our knowledge, this is the second report of docetaxel-induced supravenous discoloration and we discussed the terminology and mechanism of this unique reaction.

Discolouration of the fingernails from using hydroquinone skin-lightening cream.

A 23-year-old left-handed white male was referred with a complaint of brown discolouration of the fingernails of his left hand. He had been applying 4% hydroquinone cream to facial melasma. The discolouration began in winter and worsened in March and April. It resolved within 2 months of cessation of hydroquinone. There are only a few reports of nail staining as a result of hydroquinone in the literature. Nail discolouration as a result of hydroquinone may occur on only one hand.

Measurement of epidermal thickness in a patient with psoriasis by computer-supported image analysis

The aim of the present study was to measure full epidermal thickness, stratum corneum thickness, rete length, dermal papilla widening and suprapapillary epidermal thickness in psoriasis patients using a light microscope and computer-supported image analysis. The data obtained were analyzed in terms of patient age, type of psoriasis, total body surface area involvement, scalp and nail involvement, duration of psoriasis, and family history of the disease. The study was conducted on 64 patients and 57 controls whose skin biopsies were examined by light microscopy. The acquired microscopic images were transferred to a computer and measurements were made using image analysis. The skin biopsies, taken from different body areas, were examined for different parameters such as epidermal, corneal and suprapapillary epidermal thickness. The most prominent increase in thickness was detected in the palmar region. Corneal thickness was more pronounced in patients with scalp involvement than in patients without scalp involvement (t = -2.651, P = 0.008). The most prominent increase in rete length was observed in the knees (median: 491 æm, t = 10.117, P = 0.000). The difference in rete length between patients with a positive and a negative family history was significant (t = -3.334, P = 0.03), being 27 percent greater in psoriasis patients without a family history. The differences in dermal papilla distances among patients were very small. We conclude that microscope-supported thickness measurements provide objective results.

Subepidermal calcified nodule

Subepidermal calcified nodules are rarely seen and are classified under idiopathic subepidermal calcifications. They commonly affect children. It is most frequently encountered in the face, and it is less common in the extremities. Here, we present a case where the lesion was localized on the knees of a 23-year-old female patient