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Linear Array (linear + array)
Selected AbstractsCommentary on: Divne A-M, Nilsson M, Calloway C, Reynolds R, Erlich H, Allen M. Forensic Casework Analysis Using the HVI/HVII mtDNA Linear Array Assay.JOURNAL OF FORENSIC SCIENCES, Issue 4 2006J Forensic Sci 2005;50:54 [source] PRELIMINARY EXPERIENCE OF A PROTOTYPE FORWARD-VIEWING CURVED LINEAR ARRAY ECHOENDOSCOPE IN A TRAINING PHANTOM MODELDIGESTIVE ENDOSCOPY, Issue 2010Hiroshi Imaizumi Oblique-viewing curved linear array (OV-CLA) echoendoscopes have been widely used to perform endoscopic ultrasonography-guided fine needle aspiration and interventional endoscopic ultrasonography. Recently a prototype forward-viewing curved liner array (FV-CLA) echoendoscope was developed. In the present trial, 11 endoscopists participated in a hands-on trial and a questionnaire survey to evaluate the operation performance and visualization performance of a prototype FV-CLA scope in a phantom model designed for training of endoscopic ultrasonography. The results of our trial suggested that the FV-CLA scope is slightly inferior or equivalent to the conventional OV-CLA scope in operation performance, and that the FV-CLA scope is equivalent to the OV-CLA scope with regard to the visualization performance in a phantom model. [source] Competitive Hebbian learning and the hippocampal place cell system: Modeling the interaction of visual and path integration cuesHIPPOCAMPUS, Issue 3 2001Alex Guazzelli Abstract The hippocampus has long been thought essential for implementing a cognitive map of the environment. However, almost 30 years since place cells were found in rodent hippocampal field CA1, it is still unclear how such an allocentric representation arises from an egocentrically perceived world. By means of a competitive Hebbian learning rule responsible for coding visual and path integration cues, our model is able to explain the diversity of place cell responses observed in a large set of electrophysiological experiments with a single fixed set of parameters. Experiments included changes observed in place fields due to exploration of a new environment, darkness, retrosplenial cortex inactivation, and removal, rotation, and permutation of landmarks. To code for visual cues for each landmark, we defined two perceptual schemas representing landmark bearing and distance information over a linear array of cells. The information conveyed by the perceptual schemas is further processed through a network of adaptive layers which ultimately modulate the resulting activity of our simulated place cells. In path integration terms, our system is able to dynamically remap a bump of activity coding for the displacement of the animal in relation to an environmental anchor. We hypothesize that path integration information is computed in the rodent posterior parietal cortex and conveyed to the hippocampus where, together with visual information, it modulates place cell activity. The resulting network yields a more direct treatment of partial remapping of place fields than other models. In so doing, it makes new predictions regarding the nature of the interaction between visual and path integration cues during new learning and when the system is challenged with environmental changes. Hippocampus 2001;11:216,239. © 2001 Wiley-Liss, Inc. [source] Adaptive pattern nulling design of linear array antenna by phase-only perturbations using memetic algorithmsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 11 2008Chao-Hsing Hsu Abstract In this paper, the pattern nulling of a linear array for interference cancellation is derived by phase-only perturbations using memetic algorithms (MAs). The MAs uses improvement procedures which is obtained by incorporating local search into the genetic algorithms. It is proposed to improve the search ability of genetic algorithms. MA is a kind of an improved type of the traditional genetic algorithms. By using local search procedure, it can avoid the shortcoming of the traditional genetic algorithms, whose termination criteria are set up by using the trial and error method. The MA is applied to find the pattern nulling of the proposed adaptive antenna. This design for radiation pattern nulling of an adaptive antenna can suppress interference by placing a null at the direction of the interfering source, i.e. to increase the signal to interference ratio. This proposed method is that an innovative adaptive antenna optimization technique is also able to solve the multipath problem which exists in practical wireless communication systems. Two examples are provided to justify the proposed phase-only perturbations approach based on MAs. Computer simulation results are given to demonstrate the effectiveness of the proposed method. Copyright © 2007 John Wiley & Sons, Ltd. [source] A practical method for 2D multiple-animal MRIJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2007Marc S. Ramirez MS Abstract Purpose To investigate practical methods for achieving routine simultaneous 2D MRI of multiple animals in large-bore experimental scanners. Materials and Methods Three four-element array geometries were compared against a standard single-coil configuration in terms of image quality, ease of use, and data efficiency using a four-channel, 4.7 T small animal imaging system. Results A linear arrangement of volume resonators permits unobstructed animal preparation and use of an imaging protocol that is almost identical to the single-coil configuration without requiring any image correction or other additional postprocessing. Resulting in vivo images were visually indistinguishable from those acquired through the single-coil configuration. Conclusion The efficiency of animal studies employing 2D MRI techniques can be substantially improved by using a linear array of commercially available resonators. J. Magn. Reson. Imaging 2007;26:1162,1166. © 2007 Wiley-Liss, Inc. [source] Cervical and oral human papillomavirus types in HIV-1 positive and negative women with cervical disease in South AfricaJOURNAL OF MEDICAL VIROLOGY, Issue 6 2008Dianne J. Marais Abstract This study tested cervical and oral human papillomavirus (HPV) infection in HIV-1 seropositive (HIV+) and seronegative (HIV,) women to determine any association between infections at both sites and the difference in prevalence of the HPV types infecting these women. Participants were 115 women referred to a colposcopy clinic after diagnosis of abnormal cervical cytology. The women showed low grade cervical intraepithelial neoplasia (CIN1) or high grade disease (CIN2/3) or no CIN based on colposcopy and histology. Typing of HPV in cervical and oral cells was by Roche linear array and included direct sequencing on selected oral samples. Cervical HPV prevalence was 86.5% and 97.1% in HIV, and HIV+ women respectively. With the exception of HPV-45, prominent in HIV+ women, the hierarchy of predominant types were similar in HIV, and HIV+ women. HPV-16 was most prevalent in both HIV+ (41.7%) and HIV, women (38.5%) with CIN2/3. Significantly more HIV+ women had multiple cervical (>1) infections than HIV, women (36.1% vs. 88.2%, P,<,0.001) and more oral HPV infections (45.5% and 25% respectively; P,=,0.04). The most prevalent oral HPV types were HPV-33, -11, and -72. The majority of women did not have concordant oral and cervical HPV types, reflecting possible independence of infection at the two sites. HIV immune suppression did not impact significantly on the predominant types of cervical HPV infection (except for HPV-45). HIV+ women had more multiple HPV infections and those with severe cervical disease a similar prevalence of HIV-16 but a lower HPV-18 prevalence than HIV, women. J. Med. Virol. 80:953,959, 2008. © 2008 Wiley-Liss, Inc. [source] Maximum pixel spectrum: a new tool for detecting and recovering rare, unanticipated features from spectrum image data cubesJOURNAL OF MICROSCOPY, Issue 2 2004D. S. BRIGHT Summary A new software tool, the maximum pixel spectrum, detects rare events within a spectrum image data cube, such as that generated with electron-excited energy-dispersive X-ray spectrometry in a scanning electron microscope. The maximum pixel spectrum is a member of a class of ,derived spectra' that are constructed from the spectrum image data cube. Similar to a conventional spectrum, a derived spectrum is a linear array of intensity vs. channel index that corresponds to photon energy. A derived spectrum has the principal characteristics of a real spectrum so that X-ray peaks can be recognized. A common example of a derived spectrum is the summation spectrum, which is a linear array in which the summation of all pixels within each energy plane gives the intensity value for that channel. The summation spectrum is sensitive to the dominant features of the data cube. The maximum pixel spectrum is constructed by selecting the maximum pixel value within each X-ray energy plane, ignoring the remaining pixels. Peaks corresponding to highly localized trace constituents or foreign contaminants, even those that are confined to one pixel of the image, can be seen at a glance when the maximum pixel spectrum is compared with the summation spectrum. [source] Non-invasive assessment of motor unit anatomy in jaw-elevator musclesJOURNAL OF ORAL REHABILITATION, Issue 10 2005T. CASTROFLORIO summary The estimation of fibre length in jaw-elevator muscles is important for modelling studies and clinical applications. The objective of this study was to identify, from multi-channel surface EMG recordings, the main innervation zone(s) of the superficial masseter and anterior temporalis muscles, and to estimate the fibre length of these muscles. Surface EMG signals were collected from 13 subjects with a 16-electrode linear array. The innervation zones of the masseter and anterior temporalis were identified and their variability intra- and inter-subject outlined. More than one main innervation zone location was identified in the masseter of all subjects and in the temporalis anterior of 12 subjects. Average estimated fibre lengths, for the right (left) side, were (mean ± SD) 27·3 ± 2·4 mm (27·0 ± 1·7 mm) and 25·9 ± 2·3 mm (26·6 ± 1·6 mm), for the superficial masseter and temporalis anterior muscle, respectively. The range of innervation zone locations was up to approximately 50% of the fibre length, both within and between subjects. Fibre length estimates well matched with published data on cadavers. It was concluded that multi-channel surface EMG provides important and reliable information on the anatomy of single motor units in jaw-elevator muscles. [source] Ultrasound guidance and monitoring of laser-based fat removalLASERS IN SURGERY AND MEDICINE, Issue 10 2008Jignesh Shah MS Abstract Background and Objectives We report on a study to investigate feasibility of utilizing ultrasound imaging to guide laser removal of subcutaneous fat. Ultrasound imaging can be used to identify the tissue composition and to monitor the temperature increase in response to laser irradiation. Study Design/Materials and Methods Laser heating was performed on ex vivo porcine subcutaneous fat through the overlying skin using a continuous wave laser operating at 1,210 nm optical wavelength. Ultrasound images were recorded using a 10 MHz linear array-based ultrasound imaging system. Results Ultrasound imaging was utilized to differentiate between water-based and lipid-based regions within the porcine tissue and to identify the dermis-fat junction. Temperature maps during the laser exposure in the skin and fatty tissue layers were computed. Conclusions Results of our study demonstrate the potential of using ultrasound imaging to guide laser fat removal. Lasers Surg. Med. 40:680,687, 2008. © 2008 Wiley-Liss, Inc. [source] Testing an integrated chronology: I-Xe analysis of enstatite meteorites and a eucriteMETEORITICS & PLANETARY SCIENCE, Issue 5 2008A. BUSFIELD In the case of the enstatite meteorites the inferred ages are associated with the pyroxene-rich separates giving pyroxene closure ages relative to the Shallowater standard of Indarch (EH4, 0.04 ± 0.67 Ma), Khairpur (EL6, ,4.22 ± 0.67 Ma), Khor Temiki (aubrite, ,0.06 Ma), and Itqiy (enstatite achondrite, ,2.6 ± 2.6 Ma), negative ages indicate closure after Shallowater. No separate from the cumulate eucrite Asuka (A,) 881394 yielded a consistent ratio, though excess 129Xe was observed in a feldspar separate, suggesting disturbance by thermal metamorphism within 25 Ma of closure in Shallowater. Iodine-129 ages are mapped to the absolute Pb-Pb time scale using the calibration proposed by Gilmour et al. (2006) who place the closure age of Shallowater at 4563.3 ± 0.4 Ma. Comparison of the combined 129I-Pb data with associated 53Mn ages, for objects that have been dated by both systems, indicates that all three chronometers evolved concordantly in the early solar system. The enstatite chondrites are offset from the linear array described by asteroid-belt objects when 53Mn ages are plotted against combined 129I-Pb data, supporting the suggestion that 53Mn was radially heterogeneous in the early solar system. [source] A Computer-Based Method for Determination of the Cell-Free Layer Width in MicrocirculationMICROCIRCULATION, Issue 3 2006SANGHO KIM ABSTRACT Objectives: The cell-free layer between the erythrocyte column and the vessel wall is an important determinant of hydrodynamic resistance in microcirculatory vessels. The authors report a method for continuous measurement of the width of this layer. Methods: The light intensity of a linear array of pixels perpendicular to the vessel axis is continuously determined from a video image of a microcirculatory vessel. A threshold level based on Otsu's method is used to establish the interface between the cell-free layer and the erythrocyte column. To test the method, video images at 750,4500 frames/s were obtained from venules and arterioles in rat spinotrapezius muscle at normal and reduced arterial pressures before and after induction of erythrocyte aggregation with Dextran 500. The current measurements were compared to manual measurements of the same images. Results: Values obtained by the manual and the new methods were in agreement within the 95% confidence limit by the Bland-Altman analysis and within 90,95% range by the correlation coefficient (R2). The more frequent measurements reveal substantial, rapid variations in cell-free layer width and changes in mean values with alteration of arterial pressure and red cell aggregability. Conclusions: A new, computer-based technique has been developed that provides measurements of rapid, time-dependent variations in the width of the cell-free layer in the microcirculation. [source] Low profile DOA finder at 2.4 GHzMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2009M. Uthansakul Abstract Technique to find direction of arrival (DOA) has been promisingly constructed by smart antenna technology. It consists of array antennas and signal processing unit. Because of the limitation of space in commercial products, the size of antenna array should be designed with the smallest dimension. Also the processing unit is expected in low complexity and expense. Most of DOA finders were recently proposed employing linear array in which the size is linearly increased as a number of antenna elements. Also the processing units were fully comprised with high level of computation. In this paper, the low profile of 2.4 GHz DOA finder is proposed. The DOA finder is designed in the compact size of 2 × 2 array antennas. Using modified Butler matrix, the processing unit is very simple in which it can be handled by any economic microprocessors. The proposed finder is able to delicately specify DOA in every angle from 0° to 360°. The experimental results confirm the success of proposed DOA finder. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 252,256, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23984 [source] A new approach to the Orchard,Elliott pattern synthesis algorithm using LMS and pseudoinverse techniquesMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2001R. Shavit Abstract A new approach to the Orchard,Elliott pattern synthesis algorithm based on the least mean-square (LMS) technique and the pseudoinverse technique is described. The new algorithm offers better initial conditions and avoids possible divergence problems throughout the iteration process. The array current distribution obtained is optimized using a genetic algorithm. The effectiveness of the new approach is demonstrated on a linear array with a symmetric flat-topped radiation pattern. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 12,15, 2001. [source] Uniplanar four-element Vivaldi array fed by a coplanar waveguideMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2001I. Linardou Abstract This letter describes the design of a uniplanar parallel-series-fed linear array of Vivaldi antennas. Matching conditions have been optimized with an equivalent-circuit model. The array exhibits 12dBi gain in the substrate plane, 80% radiation efficiency, and low cross polarization over 5% bandwidth centered at 4.2GHz. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 60,62, 2001. [source] Offline, multidetector intensity interferometers , I. TheoryMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006Aviv Ofir ABSTRACT Stellar amplitude interferometry is limited by the need to have optical distances fixed and known to a fraction of the wavelength. We suggest reviving intensity interferometry, which requires hardware which is many orders of magnitude less accurate, at the cost of more limited sensitivity. We present an algorithm to use the very high redundancy of a uniform linear array to increase the sensitivity of the instrument by more than a 100-fold. When using an array of 100 elements, each almost 100 m in diameter, and conservative technological improvements, we can achieve a limiting magnitude of about mb= 14.4. Digitization, storage, and offline processing of all the data will also enable interferometric image reconstruction from a single observation run, and application of various algorithms at any later time. Coronagraphy, selectively suppressing only the large-scale structure of the source, can be achieved by specific aperture shapes. We conclude that after three decades of abandonment optical intensity interferometry deserves another review. [source] Spread of local anaesthetic solution in epidural space visualisation with ultrasound in single shot caudalsPEDIATRIC ANESTHESIA, Issue 6 2007K. Raghavan Background:, Ultrasonography is becoming an important adjunct in paediatric neuraxial blockade. Ultrasound guidance helps in visualisation of relevant neuraxial structures, predicting depth of epidural space from skin, reduction in bony contact and faster epidural placement. The visibility of neuraxial structures declines in patients as age increases. To date, there are no studies looking at the extent of spread of local anaesthetic solution in the epidural space and its correlation to the volume used, under ultrasound guidance. We report the results of our audit on spread of local anaesthetic solution in the epidural space in single shot caudal blocks. This abstract is based on the first 17 patients, the presentation will be based on all 50 patients. Methods:, This audit was approved by the local audit committee. We aimed to follow the extent of the spread of local anaesthetic within the epidural space with real time ultrasonography. Patients were selected when the planned anaesthetic included a single shot caudal block. The anaesthetists performing the anaesthetic and the caudal block consented to our ultrasound visualisation. All patients were below 5 years of age. No attempt was made to standardise the technique, the dose, or the speed of injection. After the placement of the caudal cannula by the primary anaesthetist involved in patient care, a separate anaesthetist, experienced in using ultrasound, visualised the neuraxial structures and subsequent spread of the local anaesthetic solution with real time ultrasound. The spread was followed during the injection and for 10 s after the completion of the injection. A 5 cm 7.5,12 MHz linear array was used longitudinally with either midline or paramedian approach. Results:, We are reporting the preliminary results from 17 patients. Patients were aged between 1 day and 1 year 10 months. They weighed between 3.3 kg and 14.6 kg. Either 22 gauge Jelco or Abbocath were used to perform the procedure; 0.25% or 0.20% L-bupivacaine was used on all occasions. The volume administered per kg ranged between 0.33 and 1.27 ml. The visibility of neuraxial structures was good on all occasions. On calculating the Spearmans correlation coefficient, the extent of spread of local anaesthetic in the epidural space was positively correlated with the volume used by a correlation coefficient of 0.64, with a P value of 0.008. The postoperative pain score in recovery was 0 in 16 out of the 17 cases. The one failure occurred when the observed spread would not have been expected to provide analgesia for the performed operation. Conclusions:, Among children below 5 years of age, there seems to be a positive correlation between the volume of local anaesthetic injected into the epidural space and the extent of its spread. This needs to be further investigated by a prospective randomised control trial. The utility of real time ultrasound to allow a reliable achievement of a desired level of sensory block, should be investigated i.e, whether the volume used in achieving a desired level of local anaesthetic spread, as guided by ultrasound, provides superior analgesia and fewer adverse effects compared with the volume calculated using the Armitage regimen. References, 1,Rapp HJ, Folger A, Grau T. Ultrasound guided epidural catheter insertion in children. Anesth Analg 2005; 101: 333,339. 2,Willschke H, Marhofer P, Bosenberg A, et al. Epidural catheter placement in children: comparing a novel approach using ultrasound guidance and a standard loss of resistance technique. Br J Anaesth 2006; 97: 200,207. 3,Marhofer P, Bosenberg A, Sitzwohl C et al. Pilot study of neuraxial imaging by ultrasound in infants and children. Pediatr Anesth 2005; 15: 671,676. [source] Semiconductor Nanorod Liquid Crystals and Their Assembly on a Substrate,ADVANCED MATERIALS, Issue 5 2003L.-S. Li The macroscopic alignment and superlattice structures of CdSe nanorods in a nematic liquid-crystalline (LC) phase are determined by the phases that form prior to complete solvent evaporation (e.g., vortex structures in linear arrays, see Figure). By controlling the phase of the LC solution and its orientation using pretreated surfaces or external fields, it may be possible to achieve fine control of order in deposited nanorod films. [source] A high-gain dual-band directional/omnidirectional reconfigurable antenna for WLAN systemsINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 3 2008Min Ding Abstract A high-gain dual-band antenna for the wireless local area network system is presented in this article. Two symmetrical linear arrays can be dynamically reconfigured that could switch radiation pattern with a switchable feed circuit between direction and omnidirection. The antenna can also be used for a pattern diversity antenna for the multiple-input,multiple-output communication systems. The design process for the antenna system is given, and the parameters and characteristics of the antennas are achieved by the method. Measured return losses, isolation, and radiation patterns are in good agreement with the simulated ones, which illustrates that the method is valid and the antenna system can be integrated with pattern reconfigurable and pattern diversity applications. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. [source] Hypertrophic scarring of the neck following ablative fractional carbon dioxide laser resurfacingLASERS IN SURGERY AND MEDICINE, Issue 3 2009Mathew M. Avram MD Abstract Background Ablative fractional carbon dioxide (CO2) laser treatments have gained popularity due to their efficacy, shortened downtime, and decreased potential for scarring in comparison to traditional ablative CO2 resurfacing. To date, scarring with fractional CO2 lasers has not been reported. Objective Five patients treated with the same fractional CO2 laser technology for photodamage of the neck were referred to our practices 1,3 months after treatment. Each patient developed scarring. Of the five cases, two are discussed in detail. The first was treated under general anesthesia on the face and anterior neck at a pulse energy of 30 mJ (859 µm depth) with 25% coverage. Eleven days after treatment, three non-healing areas along the horizontal skin folds of the anterior neck were noted. At 2 weeks after CO2 ablative fractional resurfacing, these areas had become thickened. These raised areas were treated with a non-ablative fractionated 1,550 nm laser to modify the wound healing milieu. One week later, distinct firm pale papules in linear arrays with mild hypopigmentation had developed along involved neck skin folds. Skin biopsy was performed. For the second patient, the neck was treated at a pulse energy of 20 mJ (630 µm depth) with 30% coverage of the exposed skin, with a total treatment energy of 5.0 kJ. Minimal crusting was noted on the neck throughout the initial healing phase of 2 weeks. She then experienced tightness on her neck. Approximately 3 weeks after treatment, she developed multiple vertical and horizontal hypertrophic scars (HS). Results Histopathology for the first case confirmed the presence of a hypertrophic scar. The papules in this case completely resolved with mild residual hypopigmentation after treatment with topical corticosteroids. HS failed to resolve in the second case to date after 1 month. Conclusion As with traditional ablative CO2 laser resurfacing, HS is a potential complication of ablative fractional CO2 laser resurfacing, particularly on the neck. With early diagnosis and appropriate treatment HS of neck skin may be reversible. We urge caution when treating the neck with this device and close attention to wound care in the post-operative period. Lasers Surg. Med. 41:185,188, 2009. © 2009 Wiley-Liss, Inc. [source] Scanning properties of sequentially rotated linear arrays of circularly polarized patch radiatorsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 5 2001Quiterio García-García Abstract This paper presents a theoretical analysis of the effect of beam scanning and amplitude tapering on the cross-pol level of sequentially rotated linear arrays composed of circularly polarized patch antenna elements. Arrays of eight elements are considered to illustrate the analysis. Several sequential phase distributions are analyzed in terms of the cross-pol level cancellation effect over the antenna field of view. These arrangements are analyzed in terms of the location of the maximum cross-pol peak levels and their values. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 343,350, 2001. [source] Progress in the Development of a High Performance Airborne Digital SensorTHE PHOTOGRAMMETRIC RECORD, Issue 96 2000P. Fricker Joint development work by LH Systems and Deutsches Zentrum für Luft- und Raumfahrt (German Aerospace Center) has produced encouraging results using forward, nadir and backward looking linear arrays on the focal plane to provide panchromatic imagery and geometric information, supplemented by further arrays to acquire multispectral imagery suitable for both high precision photogrammetric mapping and image processing for interpretative purposes. The geometric characteristics of line scanner imagery necessitate line-by-line rectification for aircraft tilts and shifts. Satisfactory execution of this process is enhanced by using supplementary data from high performance, on-board GPS and inertial measurement systems. Similarly, high demands are placed on other sub-systems, such as the camera mount, lens, electronics and storage technology. In addition to rectification for aircraft tilts and shifts, rectification for terrain characteristics is also required in order to generate colour and false colour composite images, since the various multispectral arrays are in different places on the focal plane. The special geometry affects triangulation. Thereafter, the imagery can be processed using existing software packages from both photogrammetry and remote sensing. The concept has been demonstrated in several successful test flights and the production model is scheduled for market introduction at the ISPRS Congress in July 2000. The imagery from the new sensor will fulfil many market requirements between the highest resolution film imagery (<0.1 m) and high resolution space imagery (1m to 10 m). The sensor's unique blend of multispectral information with high quality geometric information will give rise to numerous new applications. [source] X-ray studies of crystalline complexes involving amino acids and peptides.ACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2006XLIII. The asymmetric unit of the dl -lysine complex of adipic acid [bis(dl -lysinium) adipate], 2C6H15N2O2+·C6H8O42,, contains a zwitterionic singly charged lysinium cation and half a doubly charged adipate anion (the complete anion has inversion symmetry). That of the l -lysine complex (lysinium hydrogen adipate), C6H15N2O2+·C6H9O4,, consists of a lysinium cation and a singly charged hydrogen adipate anion. In both structures, the lysinium cations organize into layers interconnected by adipate or hydrogen adipate anions. However, the arrangement of the molecular ions in the layer is profoundly different in the dl - and l -lysine complexes. The hydrogen adipate anions in the l -lysine complex form linear arrays in which adjacent ions are interconnected by a symmetric O,H,O hydrogen bond. [source] |