Isopropanol sensor based on sprayed In2S3 thin film using linear discriminant analysis for real-time selectivity.

Metal sulfides have been studied for their high performance as new sensitive materials for gas detection. These material innovations contribute significantly to the development of more sensitive, stable and specific conductivity sensors, opening the way to new applications in detecting gases at low concentrations. Hence, this work reports on the sensing performance of In2S3 for isopropanol detection. Numerous VOCs, such as ketones, alcohols, and aldehydes, serve as cancer biomarkers. Notably, isopropanol, as a biomarker, shows a substantial increase (20-1007 ppb) in lung cancer patients, suggesting its potential as an early diagnostic criterion. To explore this, we fabricated a thin film of In2S3 onto a platinum interdigitated silicon dioxide substrate by simple and low-cost spray pyrolysis technology. Structural and morphological analyses via XRD, MEB, AFM, and TEM were conducted on the prepared samples. Isopropanol vapor response was assessed within a controlled temperature range of 250 °C-450 °C. The In2S3-based sensor demonstrated notable sensitivity (0.034 ppm-1), maintained stability over three weeks, and reliably detected isopropanol activation. In2S3 emerges as a promising candidate for detecting isopropanol, with a limit of detection (LOD) of 162 ppb. In this work, seven VOCs, including isopropanol, ethanol, methanol, butan-1-ol, formaldehyde, toluene, and acetone, were evaluated. Cross-responses among these VOCs were observed, indicating a lack of assured sensor selectivity. However, isopropanol recognition was achieved by employing linear discriminant analysis (LDA) on pertinent features derived from transient current change measurements. As a result, the sensor's sensitivity enables the deduction of the isopropanol concentration.

Highly responsive and selective ozone sensor based on Ga doped ZnS-ZnO composite sprayed films.

Ozone detection is currently the subject of wide scientific and technological research, motivated by its harmful impact on human safety, environment and health. With the aim of searching for new highly sensitive materials for ozone detection, Ga-doped ZnS and ZnS-ZnO films were deposited by a spray pyrolysis technique. The obtained films were annealed at 400 °C for two hours. The ozone sensing properties were investigated by measuring the sensor resistance for several ozone concentrations ranging from 30 to 120 ppb. The sensor response reveals a dependence on the gallium concentration. The best response was obtained with 4% doping gallium. The sensitivity is 4.5 ppb-1 at 260 °C and the response to 30 ppb ozone is 150. Moreover, the sensor shows high performance such as good selectivity and fast rapidity.

Chemical VOC sensing mechanism of sol-gel ZnO pellets and linear discriminant analysis for instantaneous selectivity.

This work reports on the integration of ZnO pellets for use as a virtual sensor array (VSA) of volatile organic compounds (VOCs). ZnO pellets consist of nano-powder prepared using a sol-gel technique. The microstructure of the obtained samples was characterized by XRD and TEM methods. The response to VOCs at different concentrations was measured over a range of operating temperatures (250-450 °C) using DC electrical characterization. The ZnO based sensor showed a good response towards ethanol, methanol, isopropanol, acetone and toluene vapors. We note that the highest sensitivity (0.26 ppm-1) is obtained with ethanol while the lowest one (0.041 ppm-1) corresponds to methanol. Consequently, the limit of detection (LOD) estimated analytically reached 0.3 ppm for ethanol and 2.0 ppm for methanol at an operating temperature of 450 °C. The sensing mechanism of the ZnO semiconductor was developed on the basis of the reaction between the reducing VOCs with the chemisorbed oxygen. We verify through the Barsan model that mainly O- ions in the layer react with VOC vapor. Furthermore, dynamic response was investigated to construct mathematical features with distinctly different values for each vapor. Basic linear discrimination analysis (LDA) shows a good job of separating two groups by combining features. In the same way we have shown an original reason embodying the distinction between more than two volatile compounds. With relevant features and VSA formalism, the sensor is clearly selective towards individual VOCs.

Annealing effect on the physical properties of TiO2 thin films deposited by spray pyrolysis.

Titanium dioxide (TiO2) thin films were deposited on glass substrates at 350 °C using the spray pyrolysis technique. As deposited and annealed thin films were characterized by X-ray diffraction, scanning electron microscopy, UV-VIS spectroscopy, and photodetection. Unlike the as deposited samples which were amorphous, annealed samples show an anatase phase. Films were absorbent in the UV region and the band gap energy decreases from 3.78 eV to 3.4 eV with annealing. The photoresponse of TiO2 photodetectors was recorded under UV (λ1 = 365 nm, λ2 = 254 nm) and visible light illumination by reversible switching (ON/OFF) cycles using DC electrical characterization. Photosensitive properties such as reproducible photosensitivity, responsivity, and detectivity were also studied.

[Contribution of the cryosurgery in the management of xeroderma pigmentosum]. / L'apport de la cryochirurgie dans la prise en charge du xeroderma pigmentosum.

BACKGROUND: Basal cell carcinoma (BCC) occurs frequently in young patients with xeroderma pigmentosum (XP). Because tumours are multiple and usually found on the face, alternatives to surgery are proposed. The purpose of this study was to evaluate the efficacy of cryosurgery for BCC in XP patients. PATIENTS AND METHODS: This was a retrospective study that included all instances of BCC occurring in XP patients treated by cryosurgery between January 2002 and October 2008. RESULTS: Forty-five cases of primary facial BCC and one case of relapsing BCC (16 on the cheeks, 11 on the nose, six on the face and five on the inner edge of the eye area) were treated by cryosurgery in 18 XP patients (average age: 18.7 years; sex ratio: 0.5). Mean carcinoma size was 10mm. Thirty-six tumours were nodular and 10 were nodular and ulcerated. Follow-up ranged from 16 to 60 months (mean: 30 months). Complications were rare. Cosmetic results were satisfactory. We noted 10 cases of hypopigmentation (21.7%) and one notch on the nose following treatment for recurrent BCC on a radiotherapy scar. Relapse occurred in one case (2.17%). CONCLUSION: Because of its simplicity, its good safety, its sparing of skin and its reliability of oncological outcome, cryosurgery is the treatment of choice for CBC in XP patients.

Thickness effect on VOC sensing properties of sprayed In2S3 films.

This work reports the thickness effect on the sensing performances of In2S3 material for some Volatile Organic Compounds (VOCs). In2S3 films were deposited on glass substrates by the spray pyrolysis technique. Different samples were prepared via changing the spray time in the range of 10-90 min. The film thickness varies from 0.8 µm to 6.1 µm. The X-ray diffraction results demonstrate that the In2S3 films are polycrystalline in nature and exhibit a cubic structure. Additionally, Scanning Electron Microscopy (SEM) and 3D profilometry examinations show that the surface roughness increases with the rising spray time. On the other hand, the oxygen adsorption versus working temperature was investigated. Sensing measurements with ethanol, methanol and acetone gases were carried out by a dynamic control of the current passing through the sensitive layers. The best sensitivity was obtained for the film matching a 70 min deposit time. An understanding of the detection mechanism based on the oxidation reaction between reduced vapors and chemisorbed oxygen was confirmed. The selectivity of the sensor was analyzed for several volatile organic compounds (VOCs).

Investigation of the effect of S/In molar ratio on physical properties of sprayed In2S3 thin films.

Indium sulfide (In2S3) thin films have been synthesized on glass substrates using the spray technique (CSP). The S : In molar ratio was varied from 1 to 4 in the starting solution. The Raman analysis confirms the formation of the ß-In2S3 material and the absence of a secondary phase. The EDS analysis reveals that our layers are pure. The thin film surface is free of cracks, as observed in AFM images. Optical transmission achieved 80% in the visible and near infrared region. The refractive index (n) is affected by the changes in the S/In molar ratio. The optical parameters, single oscillator energy (E 0), dispersion energy (E d) and high frequency dielectric constant (ε ∞), are calculated via the Wemple-DiDomenico model. In addition, the photoconductivity kinetics in In2S3 films for S/In = 2 were investigated and analyzed. The I-V characteristics and the photoresponse were also studied.

Comparative epidemiology of pemphigus in Tunisia and France: unusual incidence of pemphigus foliaceus in young Tunisian women.

Recent studies have suggested that in Tunisia, pemphigus foliaceus is more frequent in young women than expected. To confirm these findings, we compared the incidence rates of pemphigus in Tunisia as a whole and in a large area of France. New cases of pemphigus were detected retrospectively from dermatology departments and pathology laboratories over a 6-year period and classified as pemphigus vulgaris or foliaceus according to the pathology. In France, the incidence rate was 1.7 cases per million per year (95% confidence interval 1.4 to 2.1). Pemphigus vulgaris accounted for 73% of all cases, incidence increased with age, and the female-to-male sex ratio was 1.2. The incidence rate was significantly higher in Tunisia than in France: 6.7 cases per million per year (95% confidence interval 5.8 to 7.7); pemphigus foliaceus was more frequent (61%), the female-to-male sex ratio was 4.1, and the incidence rate was higher in young women. The incidence rate was 15.5 cases per million per year for pemphigus foliaceus among women aged 25 to 34 years and was even higher in some rural areas. No case was observed among household members or in neonates, and only one case occurred in childhood. Thus, we confirmed that the epidemiology of pemphigus in Tunisia is unusual. High rates of pemphigus foliaceus among young people living in rural areas are reminiscent of Brazilian pemphigus. However, the absence of cases among genetically related household members and during childhood, and the large predominance of women, contrast with Brazilian pemphigus.

[Cutaneous lymphoma in Tunisia: clinical profile and therapeutic results]. / Lymphomes cutanés en Tunisie: profil clinique et résultats thérapeutiques.

PURPOSE: The aim of this retrospective study was to investigate therapeutic result of cutaneous lymphoma in Tunisia. PATIENTS AND METHODS: Between January 1969 and June 1994, 100 patients with cutaneous lymphoma were referred either to Salah Azaiz Institute or the other University Hospitals of Tunisia. Fifty-one patients had epidermotropic lymphoma and 49 non-epidermotropic lesions. Eighty-seven patients received complete treatment. Puvatherapy and other local dermatologic treatments were used for early stage mycosis fungoïdes. Thirty-two patients benefited from radiotherapy, with curative dose in 28 cases. Chemotherapy including anthracyclin agents was used for high grade lymphoma. Thirteen patients had association of radiotherapy and chemotherapy. RESULTS: Five-year survival rates were 50% for patients with epidermotropic lesions and 56% for patients with non-epidermotropic cutaneous lymphoma. Statistical study has not identified any significant prognosis factor. CONCLUSION: Radiotherapy and chemotherapy are both effective. Treatment should depend on stage and histologic type.

[Kaposi's sarcoma and hypereosinophilic syndrome]. / Sarcome de Kaposi et syndrome hyperéosinophilique.

The authors report the case of a 73-year-old patient with severe Kaposi's sarcoma associated with an idiopathic hypereosinophilic syndrome. This association has not been reported until today and incites us to report this case.

[Giant cell fibroblastoma associated with Darier-Ferrand dermatofibrosarcoma in an adult]. / Association d'un fibroblastome à cellules géantes et d'un dermatofibrosarcome de Darier-Ferrand chez un adulte.

INTRODUCTION: Giant cell fibroblastoma is a rare mesenchyma tumor of childhood having many similarities with dermatofibrosarcoma protuberans in adults. OBSERVATION: We report the case of a 28-year-old woman presenting a subcutaneous inter-mammary mass associating both tumors. Immunohistochemistry showed an expression of CD 34 only by dermatofibrosarcoma protuberans cells. DISCUSSION: It is important to stress: the rarity of this association, the difficulty to confirm the diagnosis and to establish the links between these two tumors: simple association (as in our case), transformation or recurrence of giant cell fibroblastoma in dermatofibrosarcoma protuberans.

[Comparative epidemiology of pemphigus in Tunisia and France. Incidence of foliaceus pemphigus in young Tunisian women]. / Epidémiologie comparative du pemphigus en Tunisie et en France fréquence du pemphigus superficiel parmi les jeunes femmes Tunisiennes.

INTRODUCTION: Recent studies have suggested that pemphigus foliaceus is quite frequent in young Tunisian women. In order to confirm this hypothesis, we compared the incidence of pemphigus in general in Tunisia with that in the Ile-de-France region. METHOD: All new cases of pemphigus diagnosed during a 6-year period were reviewed in our dermatology and pathology laboratories. These cases were classed as pemphigus foliaceus or pemphigus vulgaris on the basis of histology reports. RESULTS: In France, the incidence was 1-7 new cases per million per year (95 p. 100 confidence interval 1.4-2.1). Pemphigus vulgaris was diagnosed in 73 p. 100 of the cases with an incidence increasing with age. Sex ratio (F/M) was 1.2. The incidence observed in Tunisia was significantly higher than that observed in France with 6.7 new cases per million per year (95 p. 100 confidence interval 5.8-7.7). Pemphigus foliaceus was more frequent (61 p. 100), the sex ratio (F/M) was 4.1. Incidence was higher in young women, with 20 new cases of pemphigus foliaceus per million per year among women from 25 to 34 years of age. These levels were higher in rural desert areas. No familial cases were observed and only one case occurred in a child. DISCUSSION: These findings confirm the specific epidemiology of pemphigus in Tunisia, which appears to be similar and also different from that in Brazilian pemphigus. As in Brazil, there was a predominance of pemphigus foliaceus in young adults living in rural areas in poor socioeconomic conditions. However in Tunisia the disease predominates significantly in women and there are no familial and rare juvenile cases.

[Skin aging]. / Le vieillissement cutané.

The skin aging is the result of the association of seven factors; chronological factor, genetic factors, exposure to ultraviolet rays (photodamage), behaviour factors, endocrinous, catabolics and mechanics factors. The treatment combine sun protection measures, topical treatment, dermatological and surgical techniques (peelings, resurfacing laser, injections of collagen, botulic toxin...). The authors intend to study clinical and anatomy-physiology aspect of skin aging, as well as different treatments.

[Oral desensitization to antitubercular agents]. / Désensibilisation orale aux anti-tuberculeux.

We report a case of hypersensitivity reaction to majors antituberculosis drugs. We have successfully performed oral desensitization to "Rifater *". We present our protocol that we compare to those proposed in the literature.

[Endo-bronchial lipoma. Apropos of a case]. / Lipome endo-bronchique. A propos d'un cas.

We report a case of an endobronchial lipoma on a 63 year-old woman, treated surgically. A literature review allows us to show the importance of fiberoptic bronchoscopy and computerized tomography in the diagnosis of this kind of benign tumors. The different aspects of treatment with recent progress represented by endoscopic resection are studied.