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The present work examines the influence of time delay introduced in the piezoelectric circuit of an excited Duffing harvester device with hardening stiffness on the vibration and voltage amplitudes. Specifically, we seek to exploit a delayed electrical circuit of the harvester to enhance its performance. We consider the case of a monostable system and we use a perturbation technique to approximate the periodic response and the corresponding voltage amplitude near the principal resonance. It is shown that for appropriate values of delay amplitude, the energy harvesting performance is improved over a certain range of coupling parameters and excitation frequencies. Numerical simulation is conducted to support the analytical predictions.

We explore quasi-periodic (QP) vibration-based energy harvesting (EH) in a forced nonlinear oscillator under time delay. The energy harvesting system consists in a delayed Duffing oscillator subject to harmonic excitation coupled to an electric circuit through an electromechanical coupling mechanism.We consider the case of primary resonance for which the frequency of the excitation is near the natural frequency of the oscillator. Application of the double-step perturbation method enables the approximation of the amplitude of the QP vibrations used to extract the average powers from the harvester device. Results shown that for a small value of delay amplitude, the periodic vibration-based EH can be extracted in a narrow range near the resonance, while QP vibration-based EH can be extracted over broad ranges of excitation. For relatively increasing value of the delay amplitude, only QP vibration-based EH can be extracted.

Abstract: Multicentric giant cell tumors of bone are rare; they represent less than 1% of all giant cell tumors. We report the case of a 24-year-old right-handed man, who presented in 1985 with a giant cell tumor of the upper end of the right humerus. After failure of conservative treatment (curettage and bone grafting), resection-arthrodesis of the shoulder with a free vascularised fibular autograft was performed. Three years later, the patient developed an osteolytic lesion of the lower end of the ipsilateral radius, involving the soft tissues and the wrist joint. He was treated with resection-arthrodesis of the wrist with a free vascularised fibular graft. View after 24 years for a new localization of the lower extremity of the humerus, which treated by curettage and bone grafting with a favorable postoperative (follow-up). The histologic study confirmed again the same diagnosis. After review of the literature, we report the uniqueness of this case report. [Copyright &y& Elsevier]

In this study, 4-hydroxy-6-methylpyran-2-one (TAL) and 4-hydroxycoumarin were converted into substituted coumarins by intramolecular translactonization under conventional reflux reaction and microwaves irradiation. The results previously reported in the literature for the products formed are often divergent. The structures of all the synthesized compounds were confirmed by pmr, cmr, and mass spectrometry [ABSTRACT FROM AUTHOR]

In the present study, the potato cultivar 'Desirée' was transformed via Agrobacterium tumefaciens strain LBA4404 containing the plasmid pBIN19 which harbors the Ribosome Inactivating Protein (rip30). The potato leaf discs were used as an explant for transformation. The in vitro regeneration parameters (percentage of callus regenerated, number of shoots per callus, percentage of regenerated roots and percentage of the transgenic plants) were evaluated. The PCR technique was used for identification of transformed plants. Southern and Western blot analyses were applied for molecular characterization of the transgenic clones. A greenhouse assay was carried out to evaluate the resistance to Rhizoctonia solani pathogen of transgenic clones expressing the rip30 gene. The results revealed that not all the plants developed in selective medium were positive for the corresponding gene using the PCR technique. Southern blot analysis demonstrated that the tested transgenic plants integrated three copies of rip30 gene into their genome. The expression of the RIP30 protein was confirmed in the leaf extracts of the transgenic clones by Western blot analysis. Resistance evaluation of the transgenic plants in greenhouse conditions showed that disease incidence and severity were reduced for R. solani.

Evaluation of the Resistance of some Varieties of Biological Potato to the Mildew Phytophthora infestans. To control the mildew, in particular in biological productions, the varietal resistance of potato could be an advantage to associate with other cultural measurements. For this purpose, sixteen varieties potentially interesting in conventional and biological production were tested with regard to the mildew. Eleven varieties were subscribed in the list A (Alaska, Arinda, Baraka, Fabula, Liseta, Mondial, Platina, Safrane, Santana, Spunta and Timate) and five are in the process of evaluation (Carréra, Cicéro, Derby, Vivaldi, and Voyager). It seemed that the mildew affected all the tested varieties. However, some of them appeared more tolerant than others. Indeed, the Derby and Voyager varieties revealed to be able to delay the starting of the disease of one month. Cicéro, Vivaldi and Timate could delay the development of mildew disease of twelve days, relatively to its appearance on susceptible varieties. Furthermore, the foliar level of destruction remained very limited compared to that on susceptible varieties and not exceed 10% for Timate. The varieties Fabula, Liséta, Carréra, Mondial, Spunta, Platina, Safrane, Arinda, Santana and Baraka showed an early and fast starting of the epidemy. In addition, the tolerance or varietal resistance could not resolve the problem when tubers are affected, since a relatively weak rate of leaves contamination is enough to cause a very important economic loss on the tubers.

In order to investigate a possible link between catalase (CAT) activity and salinity tolerance, an in vitro and in vivo study of the behavior of transgenic lines of potato (cv. ‘Désirée’) under salt stress conditions was carried out. Three groups of transgenic lines and non transformed control (DWT) were used in this study: lines expressing a bacterial catalase gene and lines repressing catalase activity by either co-suppression or anti-sense strategies. Various concentrations of NaCl were tested: in vitro 0, 25, 50 and 75 mM and in vivo 25, 50 and 75 mM. The results of this work show that the genetic modification of CAT activity affects the multiplication rate of vitroplants, as well as vegetative and physiological growth parameters under salt stress conditions. At 25, 50 and 75 mM of NaCl, over-expression (line KatE16) and repression of CAT increased and reduced respectively the multiplication rate of vitroplants. Differences between the transgenic lines and the wild type were evident in tuber yield and leaf chlorophyll content. These parameters were significantly increased in CAT over-expressing and slightly decreased in SU3 line repressed in CAT under 25 mM of salt stress. A stability of the potential quantum yield (Fv/Fm) was observed in the lines over-expressing the CAT at 25, 50 and 75 mM of NaCl. The repression of CAT was associated with a decrease of Fv/Fm value at 50 mM of NaCl. These results show that catalases contribute to salinity tolerance mechanisms in potato.

Optimization of potato genetic transformation by Agrobacterium tumefaciens using hygromycin resistance as selective marker. The objective of this work is the optimization of a genetic transformation and a regeneration protocol of transgenic plants in Solanum tuberosum cv Désirée using hygromycin resistance as selective marker. The gene Cat2 of Nicotiana plumbaginifolia and the gene SU2 of Gossypium hirsutum, both coding for catalases, have been used. Two antibiotic concentrations (5 and 10 mg . l -1 of culture medium) combined with two preculture periods (5 and 20 days) on non-selective medium were tested. Coculture medium was supplemented with 10 mg . l -1 of acetosyringone to test its effect on potato transformation. The addition of this phenolic compound to the coculture medium affected positively the regeneration aptitude of transgenic SU2 plants. Only the combination of 5 mg . l -1 of hygromycin and 20 days of preculture without antibiotic allowed the obtention of plants transformed with the gene SU2. Screening of the rooted shoots with PCR showed 45% of transgenic plants for both molecular constructions used.

Abstract: Objective. – To study effect of injection rate on spinal blockade and haemodynamic of spinal bupivacaine for Caesarean section. Study design. – Prospective and randomized. Patients and methods. – Sixty ASA I-II patients scheduled for elective Caesarean section were randomized to receive either fast (20 seconds, group R, n =30) or slow (60 seconds, group L, n =30) spinal injection of 10 mg of hyperbaric bupivacaine 0.5% associated with 25 μg of fentanyl and 100 μg of morphine. Sensory and motor blockade and haemodynamic parameters were recorded. Results. – Profiles of sensory and motor block were similar in both groups. Variations of arterial blood pressure and total dose of ephedrine were not different between R and L groups. However, the number of patient with systolic blood pressure lower than 100 mmHg were significantly lower in L group than in R group (p =0.04). Incidences of adverse effects were similar in both groups. Conclusion. – Result of the present study suggests that a slow rate of injection would induce lower incidence of hypotension induced by spinal bupivacaine for Caesarean section. [Copyright &y& Elsevier]

Neurogenic paraosteoarthropathies are ectopic ossifications which develop near the joints. They are a process of neo-ectopic osteogenesis occurring after central or peripheral neurological lesions, in some types of comas (oxygen carbon intoxication, prolonged sedation) and following peripheral traumas including burns. They inolve almost exclusively the large proximal joints of the limbs. Elbow is the second area of involvment. The purpose of our study was to analyze the results of surgical arthrolysis in 37 patients with elbow stiffness due to neurogenic osteoarthropathy of the elbow. We conducted a retrospective study of 35 patients and 37 elbows over a 25-year period. Preoperative assessment included clinical and radiological examination. Since 2003 the patients had undergone systematic elbow arthroscopy. The gold standard surgical treatment was arthrolysis. All patients underwent functional rehabilitation protocol. Outcomes were analyzed after a mean 5-year follow-up period (6 months - 10 years). Neurogenic paraosteoarthropathy was caused by head injury with coma in 58.8% of cases. Preoperative assessment showed bending stiffness in the majority of cases (88%), severe or very severe in 64.7% of cases. Intraoperatively functional elbow range of motion from -30° to 130° was obtained in 61.7% of cases and in 41% of cases in the long term. Ulnar nerve liberation was satisfactory in 92% of cases. No postoperative instability of the elbow was reported. Two patients with definitive neurological lesions had osteoma recurrence. The results were equivalent regardless surgical delay. Surgical arthrolysis is an effective treatment for neurogenic osteomas of the elbow., Competing Interests: Les auteurs ne déclarent aucun conflit d'intérêts., (© Khaled Khelil et al.)

Through a retrospective study of 70 cases of benign soft tissue tumors in the orthopedic traumatology department of the military hospital of Tunis over a 12-year period from January 2005 to December 2016, we have compared our findings to those of the literature in an attempt to identify epidemiological notions relevant to daily medical practice as epidemiological data on benign tumors of the soft parts of the hand remain few and sometimes discordant. The authors report a series of 70 active, young adults, mostly female, with a swelling at the level of the hand as the most common reason for consultation. The middle finger and index finger were the most affected fingers at equal frequencies. The key supplementary examination was the ultrasound of the soft parts. All patients were treated with a complete surgical biopsy of their tumor followed by a histological study of the surgical specimen. Three cases of recidivism were noted. Through this study, the frequency of tumors of the soft parts of the hand in a particular population (Tunisian military agents) is emphasized. Moreover, this study allowed us to confirm the data of the literature concerning the dominance of the digital localization. On the other hand, this study reports that the giant cell tumor is the most common histological type in the study population., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

We conducted a retrospective study of 35 patients with subungual exostosis of the hallux, also known as Turrett's exostosis, in the Department of Orthopedics and Traumatology at the Senior Military Hospital of Instruction of Tunis over the period between 1995 and 2015. We here summarize the outcomes of patients treated for this disease. The average age of patients was 29 years, with a sex ratio of 1.7. The median consultation time was six months. This delay in consultation was caused by a diagnostic error due to clinical picture resemblance with ingrown nail. Diagnosis was always confirmed by frontal and profile X-ray of the involved hallux. Treatment was based on total resection of the exostosis either through large ungual window or by latero-ungual approach. Anatomo-pathological examination was performed systematically. It allowed to confirm the benignity of the disease in all cases. All patients recovered and returned to their previous activity, on average, in 2 months. No patient had a recurrence.

We report a retrospective study of 20 patients treated for idiopathic cubital tunnel syndrome in a period of 10 years (2002-2011). The average age was 46 years. A profession at risk was present in the majority of cases. The treatment was surgical in all the cases. The indication for surgery was related to the importance of sensory-motor deficit, the long duration of symptoms, and the failure of conservative treatment. Two surgical techniques were used in this work: isolated neurolysis and neurolysis with anterior transposition of the ulnar nerve. There were no complications or recurrence of symptoms. After a mean follow-up of 12 months, our results evaluated thanks to the classification of Bishop were considered as excellent or good in 85% of cases and fair in 15% of cases. Prognosis factors were advanced age (more than 60 years), severity of the disease, and duration of symptoms (more than one year). The management of this affection must go through a better knowledge of the disease, for early diagnosis and appropriate treatment, only guarantees for a good result., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Multicentric giant cell tumors of bone are rare; they represent less than 1% of all giant cell tumors. We report the case of a 24-year-old right-handed man, who presented in 1985 with a giant cell tumor of the upper end of the right humerus. After failure of conservative treatment (curettage and bone grafting), resection-arthrodesis of the shoulder with a free vascularised fibular autograft was performed. Three years later, the patient developed an osteolytic lesion of the lower end of the ipsilateral radius, involving the soft tissues and the wrist joint. He was treated with resection-arthrodesis of the wrist with a free vascularised fibular graft. View after 24 years for a new localization of the lower extremity of the humerus, which treated by curettage and bone grafting with a favorable postoperative (follow-up). The histologic study confirmed again the same diagnosis. After review of the literature, we report the uniqueness of this case report., (Copyright © 2012. Published by Elsevier SAS.)

Aim: Evaluation of reconstruction results using a homodigital neurovascular island flap so as to recover long fingers loss fingertip., Patients and Methods: This was a retrospective study of 32 fingertip-flaps of long fingers practiced on 31 patients. They were young people (mean age: 28 years), often male (77.5%), and manual workers in 55%. The loss fingertip was traumatic in 87%. The fingertip reconstruction has been urgently assured, except in three initially-treated whitlow cases., Results: Four criteria value were used to value the results of coverage: Aesthetic, sensitive, functional, and socio-professional. We obtained good results in 72%., Conclusion: The homodigital neurovascular island flap is a simple and reproducible technique. It's an excellent method for fingertip reconstruction in Allen type II and III. Despite of some complications, in touch with the initial trauma, this surgery gives back a useful sensitivity and a good aesthetic aspect of the fingertip., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Aims: The purpose of the study is to evaluate the coverage of the distal tissue defect of long fingers using reversed homodigital island flap and comparison with other flaps., Patients and Method: It was a retrospective study of 28 cases of reversed homodigital island flap practiced in 28 patients to cover skin finger distal loss. The mean age was 29 years, the sex ratio was 0.17. The variety of à pédicule exclusivement vasculaire was the most used (89%). Partial necrosis of the flap was noticed only in two cases (7%). Six criteria were used to evaluate this coverage: the quality of the flap, the donor site, the neuroma formation, the cold intolerance, the mobility of the finger, and the satisfaction of the patient. A final score for every case was attributed., Results: At the middle last follow-up, the results were good in 89% and average in 11%., Conclusion: The reversed homodigital island flap is a safe method offering multiple advantages and constitutes an interesting alternative in front of the distal tissue defect of the long finger., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

Aim: Heterotopic ossification (HO) is common in head-injured patients. Ulnar nerve compression by HO at the elbow is rare. The purpose of this study was to establish a strategy for the management of ulnar nerve compression secondary to HO at the elbow., Patients and Methods: The authors report a retrospective study (2000-2008) of five cases of ulnar nerve compression at the elbow secondary to HO. All patients were male (mean age, 33 years). The HO was secondary to head injury (four cases) and severe burn (one case). According to the Dellon's classification, the ulnar nerve entrapment was severe in two cases and moderate in three. The elbow was ankylosed; the flexion deformity ranged from 60 degrees to 120 degrees. Only in one case was nerve decompression performed before HO maturation. In the other cases, elbow release and nerve decompression were done at the same time, when maturation of HO was achieved. Postoperative outcome assessment was based on the Kleiman and Bishop's score., Results: At 4 years of follow-up, the neurolysis result was excellent in one case, good in three cases, and poor in one., Conclusion: It seems that HO is not the direct cause of ulnar nerve compression, but its impairment may be increased by the nerve tension and elbow fixation that it causes. When HO is mature, neurolysis can be combined with elbow release. However, when HO maturation is not achieved early neurolysis associated with anterior transposition should be done without elbow release., (Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.)

Purpose of the Study: The aim of this study is to present an unusual lesion combining instability of the shoulder with a fracture of the coracoid process., Material and Methods: The authors have treated one case of recurrent anterior dislocation of the shoulder associated with pseudarthrosis of the coracoid process. The shoulder was stabilised by surgery using the Latarjet procedure., Discussion: The association of an anterior dislocation of the shoulder and pseudarthrosis of the coracoid process is very unusual. It is often unrecognized because of poor knowledge of this lesion or poor quality of the radiographs performed in the emergency room. The most likely mecanism is a direct impact of the humeral head against the coracoid process during the dislocation. The diagnosis requires good quality radiographs. When the shoulder is painful or unstable, surgical treatment is performed and the Latarjet procedure takes care of both the pseudarthrosis and the instability of the shoulder.

The aim of the study is to evaluate the results of the median nerve release at wrist as a part of acute carpal tunnel syndrome. This is a retrospective study about 26 cases of acute carpal tunnel syndrome following isolated injury of the wrist. Clinical evaluation of the median nerve function was performed before and after release. A classical median nerve release was performed in emergency eventually associated with stabilization of bone lesions. The population included was young, the mean age was 26 (range 4-52) years, frequently male (sex-ratio 3.5:1). The wrist trauma was direct in 75% of all cases and oftentimes with high velocity. The median nerve was deficient in the first examination. The average time from injury to surgery range from three hours to five days. The release was performed in emergency. The latest follow-up showed a complete recovery of the nerve's function in 85% and an incomplete in the rest (15%).The mean prognosis factor was the release time. Wrist trauma particularly with high velocity should lead to evaluation of median nerve function and to an emergency release when acute median neuropathy appeared.