Identifying mutations in Tunisian families with retinal dystrophy.

Retinal dystrophies (RD) are a rare genetic disorder with high genetic heterogeneity. This study aimed at identifying disease-causing variants in fifteen consanguineous Tunisian families. Full ophthalmic examination was performed. Index patients were subjected to IROme analysis or whole exome sequencing followed by homozygosity mapping. All detected variations were confirmed by direct Sanger sequencing. Mutation analysis in our patients revealed two compound heterozygous mutations p.(R91W);(V172D) in RPE65, and five novel homozygous mutations: p.R765C in CNGB1, p.H337R in PDE6B, splice site variant c.1129-2A > G and c.678_681delGAAG in FAM161A and c.1133 + 3_1133 + 6delAAGT in CERKL. The latter mutation impacts pre-mRNA splicing of CERKL. The other changes detected were six previously reported mutations in CNGB3 (p.R203*), ABCA4 (p.W782*), NR2E3 (p.R311Q), RPE65 (p.H182Y), PROM1 (c.1354dupT) and EYS (c.5928-2A > G). Segregation analysis in each family showed that all affected individuals were homozygotes and unaffected individuals were either heterozygote carriers or homozygous wild type allele. These results confirm the involvement of a large number of genes in RD in the Tunisian population

Tumor markers in breast cancer - European Group on Tumor Markers recommendations

Recommendations are presented for the routine clinical use of serum and tissue-based markers in the diagnosis and management of patients with breast cancer. Their low sensitivity and specificity preclude the use of serum markers such as the MUC-1 mucin glycoproteins ( CA 15.3, BR 27.29) and carcinoembryonic antigen in the diagnosis of early breast cancer. However, serial measurement of these markers can result in the early detection of recurrent disease as well as indicate the efficacy of therapy. Of the tissue-based markers, measurement of estrogen and progesterone receptors is mandatory in the selection of patients for treatment with hormone therapy, while HER-2 is essential in selecting patients with advanced breast cancer for treatment with Herceptin ( trastuzumab). Urokinase plasminogen activator and plasminogen activator inhibitor 1 are recently validated prognostic markers for lymph node-negative breast cancer patients and thus may be of value in selecting node-negative patients that do not require adjuvant chemotherapy. Copyright (C) 2005 S. Karger AG, Basel

Explaining drivers of farmers’ willingness for early adoption of enhanced irrigation technologies: case of Tunisia

The objective of this paper is to identify the influencing factors of farmers' willingness for early adoption of enhanced irrigation technologies in Tunisia. We estimate a multinomial logit model with data from 931 farmers in Central (Chebika) and Northern (Fernana) of Tunisia. Regression results reveal that early adoption is positively influenced by levels of extension service quality, trust in farmers' associations and extension agents, farmer's perception towards the innovation, credit access, and off-farm income. However, it is negatively affected by market access issues, risk aversion, and age. Risk, trust, and perception towards technology are important factors in driving early adoption decision. The findings imply that farmers training on water conservation technologies, financial support for innovation adoption, awareness of young farmers about the opportunities of agricultural innovation, incentives to farmers' associations in order to improve their market access, and inclusive participatory approaches during technology generation and transfer are all accelerators of early adoption of innovations by farmers

Ethical issues in monitoring and based tracking systems

Monitoring and based tracking systems use a variety of technologies to record and monitor the activities of humans. This can increase the risks to the privacy and security of individuals. The amount of information gathered about individuals is growing through the proliferation of surveillance cameras, sensors; microchips and Radio Frequency Identification RFID tags embedded in devices and products. Advances in electronic technologies allow companies and government agencies to store and process large amounts of information about individuals. The Internet provides the ultimate copier device, making this information easily available to millions. This paper highlights the ethical issues emerging with the new technologies in the monitoring and base tracking system. New regulations should be proposed to protect the individual privacy

Policy measures for reducing aquifer depletion in a context of climate change: the case of the coastal area of Cap-Bon

Groundwater resources are critically important for irrigated agriculture in Tunisia. However, excessive irrigation extractions where groundwater is slowly renewed are causing a widespread depletion of the aquifer systems, with the impacts of climate change expected to further exacerbate this problem. These circumstances call for the development of methodologies and analyses that can support the design of sustainable groundwater management policies. This paper presents a hydro-economic mathematical programming model that is used to evaluate the effects of different policy measures for reducing aquifer depletion in the Cap-Bon region of Tunisia. Three policies have been evaluated: a quota defining the maximum quantity of groundwater extractions, environmental taxation, and supply expansion with subsidized desalinated seawater. Overall, results highlight the economic and social tradeoffs among these different policy choices and the challenges facing the implementation of sustainable groundwater management in Tunisia. More specifically, results show the advantages of using subsidized desalinated seawater compared to the other two policy alternatives in terms of the value of agricultural production, farmers’ profits, and employment, despite of its sizeable budgetary burden

Development of an empirical dust storm attenuation prediction model for microwave links in arid area – a proposed framework

Wireless communication service providers are currently facing challenges due to the congested frequencies spectrum which has imposed the use of higher and higher frequencies. However, higher frequency bands are more sensitive to weather condition and the microwave signal attenuation due to atmospheric particles increases rapidly at higher frequency bands. Consequently dust storms and other phenomena cause signal attenuation which can limit the performance of wireless communication systems for the frequencies above 10GHz in arid area. The paper aim is to show that real dust storm is a complex phenomena which is difficult to be described by the theoretical physical or mathematical models. An empirical dust storm prediction model based on the long term statistical observations of dust storm properties and its corresponding microwave signal levels will be a step forward to provide microwave link designers with a precise tool to rely on. This paper has proposed a research framework to collect necessary data from Khartoum, Sudan and develop an empirical attenuation prediction model

More about in vitro grape virus symptomatology

An in vitro grafting method adapting the usual “indexing by green grafting” technique (Walter et al., 1990) to in vitro culture conditions was tested. The local grapevine varieties Khamri Tozeur, Akhel Meguergueb, Jerbi Degueche, Asli and Jebbi, infected respectively with infectious degeneration, leafroll, vein mosaic, corky bark and vein necrosis diseases, were used. Virus expression was greater on media having a greater number of nutrients such as the Van Hoof (1974) medium containing 12 macronutrients. On the other hand, the addition of BAP (0.25 mg l-1) to the medium reduced external virus symptoms on newly sprouted axillary shoots. When these shoots were transferred to fresh culture medium supplemented with IBA (0.1 mg l-1), typical and specific symptoms of major virus diseases clearly developed. Re-grafting of axillary shoots on the fragment of an infested clone can be used to overcome difficulties related to corky bark and vein mosaic symptom expression. We also demonstrated that viruses occur in general in mixed infections. The symptoms of a given virus become evident only when favourable conditions to it arise. Our research is still working on reducing the time of detecting virus and virus-like diseases. This is essential for sanitary selection of grapevine plants

Air born dust particles effects on microwave propagation in arid-area

Dust storms can degrade visibility and increase atmospheric attenuation. Therefore, microwave (MW) propagation is severely affected by dust storms in many parts of the world. Air-born dust particles may affect electromagnetic waves during a dust storm. In this paper air- born dust particles effects are studied based on measured visibility. Recent analytical and numerical models results are compared to the measured at 14 GHz. Consequently, measured attenuation is significantly greater than the predicted using recent analytical and numerical models. Dust storms can degrade visibility and increase atmospheric attenuation. Therefore, microwave (MW) propagation is severely affected by dust storms in many parts of the world. Air-born dust particles may affect electromagnetic waves during a dust storm. In this paper air- born dust particles effects are studied based on measured visibility. Recent analytical and numerical models results are compared to the measured at 14 GHz. Consequently, measured attenuation is significantly greater than the predicted using recent analytical and numerical models

Comparison between Scheduling Techniques in Long Term Evolution

Long-Term Evolution (LTE) is a recently evolving technology characterized by very high speed data rate that allows users to access internet through their mobile as well as through other electronic devices.  Such technology is intended to support variety of IP-based heterogeneous traffic types. Traffic scheduling plays an important role in LTE technology by assigning the shared resources among users in the most efficient manner. This paper discusses the performance of three types of scheduling algorithms namely: Round Robin, best Channel Quality Indicator (CQI) and Proportional Fair (PF) schedulers representing the extreme cases in scheduling. The scheduling algorithms performances on the downlink were measured in terms of throughput and block error rate using a MATLAB-based system level simulation. Results indicate that the best CQI algorithm outperforms other algorithms in terms of throughput levels but on the expense of fairness to other users suffering from bad channel conditions. ABSTRAK: Teknologi baru Evolusi Jangka Panjang (LTE) sentiasa berubah dan ia bercirikan kelajuan kadar data sangat tinggi yang membolehkan pengguna mengakses internet melalui telefon bimbit dan peranti elektronik lain. Teknologi seperti ini bertujuan menyokong pelbagai jenis trafik heterogen berasaskan IP. Penjadualan trafik memainkan peranan penting dalam teknologi LTE bagi mengagihkan sumber perkongsian secara paling berkesan di kalangan pengguna. Kertas ini membincangkan prestasi tiga jenis algoritma penjadualan iaitu: pusingan Robin, penunjuk kualiti saluran (CQI) terbaik dan  penjadualan berkadar adil (PF) yang merupakan kes ekstrem dalam penjadualan. Prestasi penjadualan Algoritma di pautan turun diukur dari segi daya pemprosesan dan kadar ralat blok melalui simulasi  sistem menggunakan MATLAB. Hasil kajian menunjukkan algoritma CQI adalah yang terbaik berbanding hasil algoritma lain dari segi tahap daya pemprosesan tetapi algoritma ini menyebabkan pengguna lain mengalami keadaan saluran buruk. KEYWORDS: LTE; round robin; best CQI; proportional fair; scheduling; resource block

Phenotypic Progression of Stargardt Disease in a Large Consanguineous Tunisian Family Harboring New ABCA4 Mutations.

To assess the progression of Stargardt (STGD) disease over nine years in two branches of a large consanguineous Tunisian family. Initially, different phenotypes were observed with clinical intra- and interfamilial variations. At presentation, four different retinal phenotypes were observed. In phenotype 1, bull's eye maculopathy and slight alteration of photopic responses in full-field electroretinography were observed in the youngest child. In phenotype 2, macular atrophy and yellow white were observed in two brothers. In phenotype 3, diffuse macular, peripapillary, and peripheral RPE atrophy and hyperfluorescent dots were observed in two sisters. In phenotype 4, Stargardt disease-fundus flavimaculatus phenotype was observed in two cousins with later age of onset. After a progression of 9 years, all seven patients displayed the same phenotype 3 with advanced stage STGD and diffuse atrophy. WES and MLPA identified two <i>ABCA4</i> mutations M1: c.[(?_4635)_(5714+?)dup; (?_6148)_(6479_+?) del] and M2: c.[2041C>T], p.[R681 <sup>∗</sup> ]. In one branch, the three affected patients had M1/M1 causal mutations and in the other branch the two affected patients had M1/M2 causal mutations. After 9-year follow-up, all patients showed the same phenotypic evolution, confirming the progressive nature of the disease. Genetic variations in the two branches made no difference to similar end-stage disease