Novel organic semiconductors based on 2-amino-anthracene: Synthesis, charge transport and photo-conductive properties.

Anthracene is considered to be a popular choice as a building block for organic semiconductors. The present work is dedicated to the synthesis and characterization of a novel semiconductor (10-OPIA) possessing mesogenic properties, which allows better control over charge transport in the bulk of a material. A novel anthracene-based molecule is characterized for its potential applications: frontier molecular energy levels are studied by optical spectroscopy and cyclic voltammetry and compared to values obtained via ab initio calculations. Thermophysical and mesogenic properties are investigated by optical microscopy and differential scanning calorimetry. Charge transport properties are characterized by means of an OFET device. It is found that this material can be easily aligned and exhibits a field effect hole mobility of 5.22 × 10-5 cm2 V-1 s-1 and an ON/OFF ratio of 104 in the device prepared by drop casting. Finally, the photoconductive properties of this novel material are addressed in order to investigate its potential applications for organic phototransistors: it exhibits a large photoconductive gain of >100 and a photo-responsivity of >1 A W-1.

Molecular p-doping in organic liquid crystalline semiconductors: influence of the charge transfer complex on the properties of mesophase and bulk charge transport.

We explore the molecular nature of doping in organic semiconductors (OSCs) by employing a liquid crystalline organic semiconductor based on phenyl naphthalene as a model. The mesophase nature of composites that include a charge transfer complex (CTC) between the OSC (8-PNP-O12) and an electron acceptor (F4TCNQ) has been investigated by means of differential scanning calorimetry, polarized optical microscopy and X-ray scattering. Optical and vibrational spectroscopies allow us to explore the characteristics and the amount of charge transfer in the CTC and expose some properties that appear only in the complexed state. We have found this system to exhibit partial charge transfer, which manifests itself in all the phase states of the host 8-PNP-O12, as well as in solution. Due to the lowering of molecular symmetry as a result of the charge transfer, one of the previously IR-only vibrational bands of the nitrile group is found to be now active in the Raman spectrum. We have also made an attempt to further investigate the influence of dopant introduction on the bulk hole mobility of 8-PNP-O12. It is found that the presence of the CTC promotes the hole transport in the Smectic B mesophase, however it seems to have a somewhat negative influence in the less ordered smectic A mesophase. This work aims to establish the link between the inevitable change of molecular geometry that occurs on charge transfer with the results obtained by spectroscopic techniques and electronic charge carrier mobility measurements.

Ionic transport in nematic liquid crystals and alignment layer effects on electrode polarization.

The physical properties of a liquid crystal-ionic liquid system were investigated. Low-frequency dielectric spectroscopy for 4-cyano-4'-pentylbiphenyl (5CB) doped with 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF 4) for the nematic and isotropic phase of host substances was performed. We obtained electrical conductivity values in the range from 298.2 K to 313.2 K and the conductivity anisotropy was confirmed. Further study of the relaxation process for bmim + allowed us to extract the relaxation frequencies and amplitudes from experimental data and confirm the temperature scaling; the thickness of the interfacial layers was estimated for the homogeneous and homeotropic alignments of the prepared composite. An attempt to unfold the ion contribution on the charge transport was made in order to better understand the electrode polarization process. In this work, the influence of the alignment layer and phase state on the interfacial layer formation in liquid crystal media will be explained better.

[Orbital and periorbital cellulitis in children. Epidemiological, clinical, therapeutic aspects and course]. / Cellulites orbitaires et péri-orbitaires de l'enfant. Profil épidémiologique, clinique, thérapeutique et évolutif.

Orbital cellulitis in children is a rare but potentially serious condition. The goal of this study is to analyze the epidemiological, clinical, therapeutic aspects and typical course of orbital and periorbital cellulitis in children, so as to propose a clinical management protocol adapted to our context. During the retrospective study period (2008-2014), 28 cases were hospitalized in the pediatric department at the Mohammed VI university medical center in Marrakech. Eighty-five percent of the cases were diagnosed as preseptal cellulitis, and 15% as retroseptal cellulitis. The age of the patients ranged from 6 months to 14 years with a mean age of 3 years. We report a female predominance with a prevalence of 58%. In our study, the most common cause is extension of infection from sinusitis. Clinically, fever was present in 19 patients (68%), eyelid edema was universal, proptosis and chemosis were noted in 2 cases, and ptosis in one patient. Bacteriological testing identified micro-organisms in 6 cases. Orbital computed tomography performed in 57% of the cases showed preseptal cellulitis in 12 cases, orbital cellulitis in one case, a subperiosteal abscess in 2 cases, and orbital abscess in one case. Medical treatment was based on amoxicillin-clavulanic acid or the combination of ceftriaxone, metronidazole±aminoglycoside. However, surgical drainage was necessary in 1 case. The outcome of all cases was favorable. Orbital cellulitis in children is usually preseptal, and amoxicillin-clavulanic acid is considered to be the standard empiric treatment.

Electric field effects on phase transitions in the 8CB liquid crystal doped with ferroelectric nanoparticles.

The influence of a low ac electric field on phase transitions is discussed in the case of a nematic liquid crystal 4-n-octyl-4^{'}-cyanobiphenyl (8CB) doped with Sn_{2}P_{2}S_{6} ferroelectric nanoparticles. The phase-transition temperatures obtained from temperature-dependent dielectric measurements were higher than those determined by the calorimetric method. This difference is explained by the presence of the measuring electric field which induces two effects. The first one is the amplification of the interactions between the nanoparticle polarization and the liquid-crystal order parameter. The second one is the field-induced disaggregation or aggregation process at high nanoparticle concentrations.

On the phase transitions of 8CB/Sn2P2S6 liquid crystal nanocolloids.

Using differential scanning calorimetry measurements, the influence of Sn2P2S6 ferroelectric nanoparticles on the phase transition temperatures of the 8CB liquid crystal is studied. The spontaneous polarization, ionic and anchoring effects are discussed. For low concentration of dopant, the global effect leads to a decrease and an increase of the nematic-isotropic and the smectic A-nematic phase transition temperatures, respectively. For high concentrations, due to aggregates formation, the predominant anchoring effect induces a decrease of the both phase transition temperatures.

Insulin-based strategies to prevent hypoglycaemia during and after exercise in adult patients with type 1 diabetes on pump therapy: the DIABRASPORT randomized study.

AIMS: To validate strategies to prevent exercise-induced hypoglycaemia via insulin-dose adjustment in adult patients with type 1 diabetes (T1D) on pump therapy. METHODS: A total of 20 patients randomly performed four 30-min late post-lunch (3 h after lunch) exercise sessions and a rest session: two moderate sessions [50% maximum oxygen consumption (VO2 max)] with 50 or 80% basal rate (BR) reduction during exercise + 2 h and two intense sessions (75% VO2 max) with 80% BR reduction or with their pump stopped. Two additional early post-lunch sessions (90 min after lunch) were analysed to compare hypoglycaemia incidence for BR reduction versus bolus reduction. RESULTS: In all, 100 late post-lunch sessions were analysed. Regardless of exercise type and BR reduction, no more hypoglycaemic events occurred in the period until the next morning than occurred after the rest sessions. In the afternoon, no more hypoglycaemic events occurred with 80% BR reduction/moderate exercise or with pump discontinuation/intense exercise than for the rest session, whereas more hypoglycaemic events occurred with 50% BR reduction/moderate exercise and 80% BR reduction/intense exercise. After early post-lunch exercise (n = 37), a trend towards fewer hypoglycaemic episodes was observed with bolus reduction versus BR reduction (p = 0.07). Mean blood glucose fell by ∼3.3 mmol/l after 30 min of exercise, irrespective of dose reduction, remaining stable until the next morning with no rebound hyperglycaemia. CONCLUSION: In adults with T1D, to limit the hypoglycaemic risk associated with 30 min of exercise 3 h after lunch, without carbohydrate supplements, the best options seem to be to reduce BR by 80% or to stop the pump for moderate or intense exercise, or for moderate exercise 90 min after lunch, to reduce the prandial bolus rather than the BR.

[Floating elbow: retrospective study and review of literature]. / Le coude flottant : étude rétrospective et revue de la littérature.

The floating elbow represents an uncommon combination of lesions in traumatology. Few studies have described this lesion especially in adults. Over a period of 6 years, 12 floating elbows were reviewed retrospectively. One osteoporotic elderly patient was treated conservatively. Reduction and internal fixation using different implants was performed in the other patients. Consolidation was obtained at the humerus at 3 months (2.5-3.5 months) on average, and 2.6 months (2-3 months) at forearm bones. According to the classification of Lange and Foster, our functional results were good in 67% of cases, fair in 17% and poor in 16% cases. Good functional prognosis of the upper limb requires rapid and adequate management of floating elbows. Internal fixation followed by early rehabilitation is recommended. The choice of surgical acts depends on the location of fractures. This strategy gave satisfactory results.

[Permanent abduction of the little finger without ulnar nerve palsy: a case report]. / Abduction permanente isolée du cinquième doigt sans paralysie ulnaire. À propos d'un cas.

Wartenberg's sign, or permanent abduction of the little finger, occurs in the context of sequelae of ulnar nerve palsy. Its presence alone is rarely reported in the literature and is due to avulsion of the insertion of the third volar interosseous muscle. Several surgical techniques to correct this sign are reported in the literature. The authors report the case of a Wartenberg's sign without ulnar nerve palsy due to traumatic avulsion of the third volar interosseous muscle that was treated by a transfer of the extensor digiti minimi onto the radial side of the extensor digitorium communis according to technique of Bellan et al. After 1-year follow-up, result was good with no recurrence of any deformities and a normal active extension.

Telemedicine and diabetes: achievements and prospects.

Health authorities currently have high expectations for telemedicine (TM), as it addresses several major challenges: to improve access to healthcare (especially for patients in underserved or remote areas); to overcome the scarcity of specialists faced with epidemic disease; and to reduce the costs of healthcare while improving quality. The aims of TM in the field of diabetes differ according to the type of diabetes. In type 1 diabetes (T1DM) associated with complex insulin regimens, the goal of TM is to help patients achieve better control of their blood glucose levels through accurate adjustment of insulin doses. In type 2 diabetes (T2DM), while therapeutic adjustments may be necessary, improvement in blood glucose control is based primarily on behavioural changes (reduced calorie and carbohydrate intakes, increased physical activity). Many TM studies focusing on management of blood glucose levels have been published, but most failed to demonstrate any superiority of TM vs traditional care. While previously published meta-analyses have shown a slight advantage at best for TM, these meta-analyses included a mix of studies of varying durations and different populations (both T1DM and T2DM patients, adults and children), and tested systems of inconsistent quality. Studies published to date on TM suggest two currently promising approaches. First, handheld communicating devices, such as smartphones, loaded with software to apply physicians' prescriptions, have been shown to improve glycaemic control. These systems provide immediate assistance to the patient (such as insulin-dose calculation and food choice optimization at meals), and all data stored in the smartphone can be transmitted to authorized caregivers, enabling remote monitoring and even teleconsultation. These systems, initially developed for T1DM, appear to offer many possibilities for T2DM, too. Second, systems combining an interactive Internet system (or a mobile phone coupled to a remote server) with a system of communication between the healthcare provider and the patient by e-mail, texting or phone calls have also shown certain benefits for glycaemic control. These systems, primarily aimed at T2DM patients, generally provide motivational support as well. Although the individual benefits of these systems for glycaemic control are fewer than with smartphones, their widespread use should be of particular value for overcoming the relative shortage of doctors and reducing the health costs associated with a disease of such epidemic proportions.

Telemedicine: what more is needed for its integration in everyday life?

The Health Authorities have huge expectations of telemedicine (TM): improved patient access to healthcare, a solution to the shortage of doctors in the face of an exponentially expanding disease, and reduced healthcare costs with improved quality. There are a host of applications for TM in the area of diabetes. TM has been validated and has been widely used to screen for diabetic retinopathy, and a number of studies are currently underway for the follow-up of diabetic foot ulcers. However, the main indication of TM remains the follow-up and control of blood glucose. In this area, many studies have been conducted to improve glycaemic control. While most of these studies have failed to show any benefits vs. conventional care, a small number have demonstrated great efficacy of this approach with regard to glycaemia. Using these studies, we attempt to define the key qualities of a successful TM system. How can we extend the results of these experiments beyond the framework of clinical studies and integrate them in daily practice so as to improve diabetes management? This is the key challenge for TM, implementation of which will require reorganization of healthcare, given the evolution of medical demographics. This reorganization will involve healthcare providers specialized in diabetes that may intervene in assigning physicians for especially distressed patients. However, such reorganization will require medico-economic evaluation before it can be implemented on a larger scale.

Linear and non-linear dielectric properties of a short-pitch ferroelectric liquid crystal stabilized by a polymer network.

Linear and non-linear dielectric measurements were carried out on a ferroelectric liquid crystal stabilized by an anisotropic polymer network. The polymerization process was achieved at room temperature. It was performed from an achiral monomer in the ferroelectric chiral smectic C phase, exhibiting a very short helical pitch and a large polarization. The linear and non-linear dielectric spectroscopy were also completed by textural morphology as well as structural and ferroelectric characterizations. All these measurements were carried out on a pure ferroelectric liquid crystal material and on composite films containing two polymer concentrations. The increase of the polymer network density leads to a decrease of the dielectric strength determined in the linear and non-linear dielectric spectroscopy. The complementarity between the linear and non-linear dielectric measurements and their confrontation with a theoretical model allowed the simultaneous determination of some physical parameters such as macroscopic polarization, rotational viscosity and twist elastic energy. We also discuss the effect of the polymer network density on the obtained physical parameters.

[Intravascular papillary endothelial hyperplasia of the ankle: a case report]. / Hyperplasie endothéliale papillaire intravasculaire de la face antérieure de cheville : à propos d'un cas.

Intravascular papillary endothelial hyperplasia (IPEH) is an unusual, benign, non-neoplasic, vascular lesion characterized histologically by papillary fronds lined by proliferating endothelium. This lesion has the propensity to occur in the skin and the subcutis. Many histological features are similar to those of low-grade angiosarcoma, a common, but more serious condition. Clinical and histological differentiation is important to avoid overtreatment of this benign lesion. We report a case of cutaneous IPEH in the ankle of a 30-year-old girl, which was successfully treated by excision. The pathologic findings, differential diagnosis and a review of recent literature are discussed.

[Isolated echinococcosis of the flexor digitorum profondus: a case report]. / Echinococcose isolée du muscle flexor digitorum profondus : à propos d'un cas.

Echinococcosis is a widespread zoonosis which is endemic in most sheep-raising countries. Primary isolated muscular localisation is uncommon even in these endemic areas. The authors report a rare case of primary hydatid cyst localized in the myotendinous junction of the flexor digitorum profundus. According to our review of the medical literature, there are no reports of a similar case, making ours the first such report.

[Insulated leg pilomatrixoma: a rare localization]. / Pilomatricome isolé de la jambe. Une rare localisation.

Pilomatrixoma is a benign skin neoplasm of the hair follicle. It's common in the pediatric population. It's usually misdiagnosed and confused with other skin lesions. Head and neck represent the usual locations. The extremity remains an exceptional location. Through an observation of a pilomatrixoma of the leg in an adult patient treated surgically without recurrence, different diagnostic and therapeutic aspects of this pathology will be recalled.

[Ischemic fasciitis. A case report]. / La fasciite ischémique. A propos d'un cas.

Ischemic fasciitis, also called atypical decubital fibroplasia, was recently described as a distinctive fibroblastic proliferation occurring predominantly in elderly, bed-ridden individuals. It is very rare. Forty cases only are reported in the literature. We report the observation of a 50-year-old patient, having an antecedent of prolonged confinement, who presents since 1 year a tumefaction compared to the higher end of the tibia of soft consistency with inflammatory signs in glance. The pathologic examination shows a pseudo tumoral lesion of ischemic fasciite type. Through this observation, we suggest to review the various problems of diagnostic differentials in particular with a sarcoma of soft tissues and to discuss the anatomoclinic features of this recent description lesion.

[Acute traumatic dislocation of the trapeziometacarpal joint treated by percutaneous pinning. Review of six cases]. / La luxation trapézométacarpienne post-traumatique récente traitée par brochage selon Wiggins. A propos de six cas.

The authors report a series of six cases of acute traumatic dislocation of the trapeziometacarpal joint of the thumb. Displacement was always dorso-radial. There were associated osseous lesions in one patient: avulsion of the palmar tubercle of the base of the first metacarpal with a fracture of the trapezoid. All the patients were treated immediately by percutaneous pinning according to the technique of Wiggins. The late results, evaluated at an average of 19 months postinjury (range: 8-29 months), were considered to be satisfactory in the majority of the patients. Treatment by percutaneous pinning remains a less sophisticated alternative that in our experience yields consistently good results, provided there is no preexisting degenerative articular lesion.

Dislocation of the carpometacarpal joint of the thumb associated with trapezium and Bennett's fractures.

We report a case of a 30-year-old man with a carpometacarpal joint dislocation of the thumb associated with trapezium and Bennett's fractures. This combined injury pattern appears to be very rare. Since, to our knowledge a similar case was not found in the literature. The lesion was managed with closed reduction and percutaneous pinning, resulting in good functional outcome.

[Bipolar forearm dislocation or floating forearm (a case report)]. / La luxation bipolaire de l'avant-bras ou avant-bras flottant (à propos d'un cas).

Bipolar dislocation of the forearm or floating forearm is a rare injury. It combines concomitant elbow and wrist dislocation. Only six cases have been reported in the literature. The diagnosis of wrist dislocation may initially be missed and therefore the prognosis will be worse. The authors report a case of a bipolar dislocation with a posterior dislocation of the elbow and a perilunate dislocation of the wrist.