In situ reflectance measurements and TM data of some sedimentary rocks with emphasis on white sandstone,southwestern Sinai,Egypt

This work presents the results of in situ reflectance measurements and Landsat-TM data analysis for some sedimentary rocks exposed in southwestern Sinai. Particular emphasis was given to white sandstone. In situ reflectance measurements were carried out in four selected sites (Musaba Salama, Abu Natash, El Dehisa and Abu Qafas areas) to define the distinctive surface reflectance patterns caused by the abundance of silicates, carbonates, clay minerals and iron oxides in white sandstone and other sedimentary rock types (clay, kaolin, limestone and dolomite). Moreover, in situ measured radiometric data were used to establish the theoretical basis for lithological discrimination.

Enhanced band ratios (2/3, 3/4, 4/5 and 5/7) and colour stretched ratio composite (2/3, 3/4 and 5/7) of the TM data 25 January 1984 of the Musaba Salama area were utilized to identify rocks rich in silicates and thereby to distinguish the white sandstone. The results demonstrated that the processed TM data can be used reliably in arid regions to distinguish white sandstone from other sandstone varieties as well as other rock types (limestone, dolomite, kaolin and shale).     

Wavelet based local tomographic image using terahertz techniques

Terahertz computed tomography has been developed based on coherent THz detection and filtered back projection (FBP) algorithms, which allows the global imaging of the internal structure and extraction of the frequency dependent properties. It offers a promising approach for achieving non-invasive inspection of solid materials. However, with traditional CT techniques, i.e. FBP algorithms, full exposure data are needed for inverting the Radon transform to produce cross sectional images. This remains true even if the region of interest is a small subset of the entire image. For time-domain terahertz measurements, the requirement for full exposure data is impractical due to the slow measurement process. This paper explores time domain reconstruction of terahertz measurements by applying wavelet-based filtered back projection algorithms for recovery of a local area of interest from terahertz measurements within its vicinity, and thus improves the feasibility of using terahertz imaging to detect defects in solid materials and diagnose disease states for clinical practise, to name a few applications.     

Economic evaluation of pregnancy diagnosis in dairy cattle: a decision analysis approach

Cost-benefit evaluations of several pregnancy diagnosis schemes were performed. The strategy using on-farm milk progesterone test on d 19 after service, followed by treatment of nonpregnant cows with prostaglandin, was the most profitable returning $10.50 per cow above the cost of the intervention. An increase in efficiency of detection of estrus of greater than 20% among cows diagnosed nonpregnant and an error rate in pregnancy diagnosis of less than or equal to 3% were needed to ensure profitability. Pregnancy diagnosis by uterine palpation per rectum on d 35 after service, combined with the use of pressure-sensitive mounting devices on nonpregnant cows was the second most profitable strategy and returned $5.10 per cow. An increase in efficiency of detection of estrus of greater than or equal to 20% was required to ensure profitability. Embryonic mortality was also critical and an increase from a baseline value of 10% to 12%, as a result of early uterine palpation, made this scheme unprofitable ($-4.80 per cow). Pregnancy diagnosis by uterine palpation per rectum at 50 or 65 d was less profitable, with a return of $2.50 and $.10 per cow, respectively.     

Huntingtin-associated protein 1 (HAP1) interacts with the p150Glued subunit of dynactin

Huntington's disease (HD) is an inherited neurodegenerative disease caused by expansion of a polyglutamine repeat in the HD protein huntingtin. Huntingtin's localization within the cell includes an association with cytoskeletal elements and vesicles. We previously identified a protein (HAP1) which binds to huntingtin in a glutamine repeat length-dependent manner. We now report that HAP1 interacts with cytoskeletal proteins, namely the p150 Glued subunit of dynactin and the pericentriolar protein PCM-1. Structural predictions indicate that both HAP1 and the interacting proteins have a high probability of forming coiled coils. We examined the interaction of HAP1 with p150 Glued . Binding of HAP1 to p150 Glued (amino acids 879-1150) was confirmed in vitro by binding of p150 Glued to a HAP1-GST fusion protein immobilized on glutathione-Sepharose beads. Also, HAP1 co-immunoprecipitated with p150 Glued from brain extracts, indicating that the interaction occurs in vivo . Like HAP1, p150 Glued is highly expressed in neurons in brain and both proteins are enriched in a nerve terminal vesicle-rich fraction. Double label immunofluorescence experiments in NGF-treated PC12 cells using confocal microscopy revealed that HAP1 and p150 Glued partially co-localize. These results suggest that HAP1 might function as an adaptor protein using coiled coils to mediate interactions among cytoskeletal, vesicular and motor proteins. Thus, HAP1 and huntingtin may play a role in vesicle trafficking within the cell and disruption of this function could contribute to the neuronal dysfunction and death seen in HD.     

Role of diameter differences among follicles in selection of a future dominant follicle in mares

Follicles > or = 5 mm were ablated in pony mares by a transvaginal ultrasound-guided technique on Day 10 (ovulation = Day 0). Follicle emergence (at 15 mm, experiment 1; at 6 mm, experiment 2) and development of the new wave was monitored by transrectal ultrasound. Deviation was defined as the beginning of a marked difference in growth rates between the two largest follicles. In experiment 1, mares were grouped (n = 4 per group) into controls, ablation-controls (ablations at Day 10 only), and a two-follicle model (periodic ablation sessions so that only the two largest follicles developed). There were no significant indications that the two-follicle model altered follicle diameters, growth rates, or time intervals of the two retained follicles at or between events (follicle emergence, deviation, and ovulation). In experiment 2, the two-follicle model (n = 14) was used for follicle and hormonal characterization and hypothesis testing, without the tedious and error-prone necessity for tracking many (e.g., 20) individual follicles. The future dominant follicle emerged a mean of 1 day earlier (p < 0.008) than the future subordinate follicle, the growth rates for the two follicles between emergence and deviation (6 days later) did not differ, and the dominant follicle was larger at the beginning of deviation (23.1 +/- 0.8 mm versus 19.6 +/- 0.9 mm; p < 0.0001). Mean FSH and LH concentrations increased (p < 0.05) concomitantly from emergence of the future dominant follicle and peaked 3 days later when the follicle was a mean of 13 mm. Thereafter, the two hormones disassociated until ovulation: FSH decreased and LH increased. Results supported the hypothesis that the future dominant follicle has an early size advantage over future subordinate follicles and indicated that the advantage was present as early as 6 days before deviation.     

Exploring the unique pharmacology of a novel opioid receptor, ZFOR1, using molecular modeling and the `message-address' concept

Previous studies have probed the structural basis of ligandselectivity in the mu, delta and kappa opioid receptors throughthe application of molecular modeling techniques in concertwith the `message–address' concept. Here, this approachwas used in an attempt to rationalize the unique pharmacologicalprofile of a recently cloned novel opioid receptor, ZFOR1 (ZebraFishOpioid Receptor 1). Specifically, a model of the transmembranedomains of ZFOR1 was constructed and used to explore the bindingmodes of various prototypical opioid ligands. The results showthat the `message' portion of the binding pocket of ZFOR1 ishighly conserved; hence, the binding modes of non-selectiveopioid ligands are well preserved. In contrast, a small numberof variant residues at the extracellular end of the bindingpocket, particularly Lys288 (VI:26) and Trp304 (VII:03), areshown to create adverse steric interactions with all delta andkappa selective ligands examined, thereby disrupting their bindingmodes. These results are consistent with, and serve as an explanationfor, the observed pharmacology of this receptor, lending supportto both the validity of the `message–address' conceptitself and to the use of molecular modeling approaches in itsapplication.     

Structural reorganization of the cerebral capillary wall in the Baikal seal Pusa sibirica during diving]

INTRODUCTION: The most common fat-suppressed sequence used to study skeletal conditions is the STIR sequence which has shown high sensitivity in the detection of skeletal lesions and whose main drawback is its long acquisition time. Currently, Turbo-STIR (T-STIR) sequences can shorten the acquisition time. The purpose of this study was therefore to compare the conventional STIR sequence with the new T-STIR sequence in the study of skeletal conditions to compare their diagnostic yield. MATERIAL AND METHODS: Twenty patients with different types of skeletal lesions were examined. MR examinations were performed with a Philips Gyroscan S15/ACS II unit (1.5 T). All the patients underwent a STIR sequence (TR/TE = 1500/20, TI = 180 ms, matrix = 204 x 256, NEX = 2, slice thickness = 5 mm, acquisition time = 9 min 24 s) and a T-STIR sequence (TR/TE = 1500/20, TI = 180 ms, matrix = 204 x 256, NEX = 2, slice thickness = 5 mm, TFL = 3, acquisition time = 3 min 33 s). The images were evaluated by measuring both quantitative parameters--percent contrast (%C), contrast to noise ratio (C/N), signal to noise ratio (S/N)--and qualitative parameters--lesion conspicuity, margins and extension, motion artifacts, image quality. RESULTS: The only statistically significant difference between the two sequences was image quality, which was superior in the conventional STIR sequence (p < .05). No statistically significant difference was demonstrated with the quantitative evaluation. DISCUSSION: In this study, T-STIR sequences were performed with low-high acquisition profile to acquire an actual echo time of 20 ms which permits to obtain optimal S/N with good spatial resolution. Therefore, T-STIR sequences with low-high acquisition profile provides better results than T-STIR sequences with linear acquisition profile which permits to obtain an actual echo time of 40 ms. CONCLUSION: This work shows that T-STIR sequences can replace conventional STIR sequences in the study of skeletal conditions reducing the acquisition time by 60%. This result can be obtained only by an accurate optimization of acquisition parameters.