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When a fundamental discovery is a fact new ground for new discoveries generally opens up. Therefore science has a tendency to progress in a stepwise manner. Naturally, this is not an automatic process and the new fields opened up may, for the favourable growth of new ideas, be ‘seeded’ by previous knowledge, scientific intuition and stimulation — and still there will be no guarantee for scientific progress.

Assessing variation in animal coloration is difficult, as animals differ in their visual system properties. This has led some to propose that human vision can never be used to evaluate coloration, yet many studies have a long history of relying on human vision. To reconcile these views, we compared the reflectance spectra of preserved avian plumage elements with two measures that are human biased: RGB values from digital photographs and the corresponding reflectance spectra from a field guide. We measured 73 plumage elements across 14 bird species. The field guide reflectance spectra were drastically different from that of the actual birds, particularly for blue elements. However, principal component analyses on all three data sets indicated remarkably similar data structure. We conclude that human vision can detect much of the variation in coloration in the visible range, providing fodder for subsequent studies in ecology, evolution, behavior, and visual ecology.

Aims: Chronic diseases impose a substantial healthcare burden. This study sought to evaluate the clinical and economic impact of new disease management (DM) programs, targeting four major chronic d...

Canada’s National Forest Inventory (NFI) sampling program is designed to support reporting on forests at the national scale. On the other hand, continuous maps of forest attributes are required to support strategic analyses of regional policy and management issues. We have therefore produced maps covering 4.03 × 106 km2 of inventoried forest area for the 2001 base year using standardised observations from the NFI photo plots (PP) as reference data. We used the k nearest neighbours (kNN) method with 26 geospatial data layers including MODIS spectral data and climatic and topographic variables to produce maps of 127 forest attributes at a 250 × 250 m resolution. The stand-level attributes include land cover, structure, and tree species relative abundance. In this article, we report only on total live aboveground tree biomass, with all other attributes covered in the supplementary data ( http://nrcresearchpress.com/doi/suppl/10.1139/cjfr-2013-0401 ). In general, deviations in predicted pixel-level values from those in a PP validation set are greater in mountainous regions and in areas with either low biomass or sparse PP sampling. Predicted pixel-level values are overestimated at small observed values and underestimated at large ones. Accuracy measures are improved through the spatial aggregation of pixels to 1 km2 and beyond. Overall, these new products provide unique baseline information for strategic-level analyses of forests ( https://nfi.nfis.org ).

The objective of this study was to determine whether the protein Zhangfei could suppress the unfolded protein response (UPR) and growth of osteosarcoma cells. Dog (D-17) and a human (Saos-2) osteosarcoma cells were infected with adenovirus vectors expressing either Zhangfei or the control protein beta- galactosidase. We monitored cell growth as well as levels of UPR gene transcripts and proteins. We found that Zhangfei suppressed the growth of both D-17 and Saos-2 cells. Zhangfei-expressing D-17 cells displayed large vacuoles containing culture medium and expressed phosphatidylserine on their external surface suggesting that Zhangfei induced macropinocytosis and apoptosis in these cells. While Zhangfei inhibited the growth of both D-17 and Saos-2 cells, it inhibited thapsigargin-induced UPR, as detected by a decrease in transcripts for UPR genes, and HERP and GRP78 proteins, only in D-17 cells, suggesting that the ability of Zhangfei to suppress the UPR and tumour cells growth may not be linked.

As the number of operational wind scatterometers is getting smaller, other sources of spaceborne sensors are now included in global wind mapping. One of the prominent sensors is the Synthetic Aperture Radar (SAR). Besides serving as a generic scatterometer, SAR systems are the only type of radar systems that can provide sub-km resolution sea surface wind data and offers near shore mapping capability. This unique feature is important for assessing the offshore wind resources. As an important source of renewable energy, offshore wind farms are growing rapidly. Furthermore, recent research shows that the cross-polarization radar backscatter does not seem to saturate in high winds, and provides an excellent supplement for scatterometer wind sensing in storm conditions. The saturation issues of co-polarization radar returns have so far made it difficult to resolve wind speeds beyond roughly 20 m/s, or even less for lower incidence angles. The scope of this paper is to show the potential of RADARSAT-2's polarimetric modes for wind speed retrieval. RADARSAT-2 is the first operational fully polarimetric (HH VV HV VH) C-band satellite. Standard Quad-pol images have been collected in the St. Lawrence Gulf and compared against the Mont-Louis buoy and QuikSCAT scatterometer data. Co-polarization wind speeds were computed with CMOD-5 algorithms. A few polarization ratios were tested to determine the most suitable one for RADARSAT-2's HH polarization mode. For Cross-polarization, two different models were compared. Cross-polarization gives excellent results when wind exceeds 5 m/s. In general, SAR wind retrieval is suitable for resolution of 400 m.

Resume Objectif. – Examiner un syndrome qui peut se rencontrer au Canada et qui est assez mal connu dans la litterature francophone. Le Koro est un trouble psychiatrique habituellement decrit comme un syndrome specifique a certaines cultures asiatiques, se manifestant par une anxiete intense associee a la crainte d'une retraction du penis dans l'abdomen qui peut mener a la mort. Meme si quelques cas ont ete rapportes chez des sujets non asiatiques, le trouble est generalement decrit comme un syndrome specifiquement culturel. Methode. – Revue de litterature classique et description de cas ; les auteurs font une description de cas de Koro rencontres dans leur pratique clinique et ouvrent une discussion sur des aspects cliniques, epidemiologiques et etiologiques de ce syndrome. Resultats. – Il semble qu'une distinction doit etre faite entre les presentations epidemiques de Koro qui sont culturellement specifiques et les cas isoles qui peuvent apparaitre dans toute culture.

The objective of this study was to determine whether the protein Zhangfei could suppress the unfolded protein response (UPR) and growth of osteosarcoma cells. Dog (D-17) and a human (Saos-2) osteosarcoma cells were infected with adenovirus vectors expressing either Zhangfei or the control protein beta- galactosidase. We monitored cell growth as well as levels of UPR gene transcripts and proteins. We found that Zhangfei suppressed the growth of both D-17 and Saos-2 cells. Zhangfei-expressing D-17 cells displayed large vacuoles containing culture medium and expressed phosphatidylserine on their external surface suggesting that Zhangfei induced macropinocytosis and apoptosis in these cells. While Zhangfei inhibited the growth of both D-17 and Saos-2 cells, it inhibited thapsigargin-induced UPR, as detected by a decrease in transcripts for UPR genes, and HERP and GRP78 proteins, only in D-17 cells, suggesting that the ability of Zhangfei to suppress the UPR and tumour cells growth may not be linked.

Experience with 81 gas computed tomography (CT) cisternography procedures in 79 patients in searching for acoustic neuroma is reported. Twenty-one tumors, four exclusively intracanalicular, were demonstrated after standard contrast-enhanced CT was negative. Fifty-five examinations were negative; four were inconclusive. The high resolution scanner with digital localization and reconstruction zoom capability greatly improved image detail. In nine of the 12 normal patients examined with it, the intracanalicular bundle was demonstrated. Substitution of carbon dioxide for air greatly reduced the morbidity of acute post-spinal tap headache. The procedure takes 30--45 min and can be performed on an outpatient basis. It is recommended as the procedure of choice when standard CT is negative in subjects clinically suspected of having acoustic neuroma.

The normal gross and computed tomographic (CT) anatomy of the infrahyoid neck is reviewed. Special emphasis is given to the location of major lymph node chains. Key anatomical levels in the neck are identified, enabling the interpreter of CT scans to place any lesion accurately in space.

Anatomical relationships of temporal bone structures are demonstrated by thin section edge detection computed tomography. Many otic structures are best appreciated in axial view, but reorientation to anatomy as seen in this plane is needed for optimal diagnosis. A level by level review of key structure is presented toward this end. The limitations and advantages of computed tomography are discussed.

We report on the appearance of parathyroid, thyroid, and cervical thymic cysts on computed tomography (CT) scans. The differential diagnostic considerations include thyroglossal and branchial cleft cysts, cystic hygromas, primary and metastatic tumors, dermoids, teratomas, choristomas, tracheoesophageal and cervical bronchogenic cysts, as well as cystic neuromas, abscesses, and lipomas. Most cannot be differentiated using CT alone and require clinical observations, laboratory testing, and surgical and histologic findings for definitive diagnosis. Our experience with these rare lesions is reported, and the differential diagnoses are discussed.

Previously it has been very difficult or impossible for radiologists to delineate accurately the size and extent of glomus tympanicum tumors. By utilizing axial transverse and coronal computed tomography detailed enlargement techniques we have been able to accurately demonstrate four such lesions. We believe that this mode of investigation is now the method of choice for glomus tympanicum tumors.

A retrospective analysis of surgically proved cases of thyroglossal duct cysts was performed in an attempt to determine the characteristics of these lesions using computed tomography (CT). We evaluated 12 preoperative cases and two cases with postoperative complications. Ten patients with lesions that could be confused either clinically or radiographically with these cysts were also evaluated to develop a systemized radiologic differential diagnostic approach for the evaluation of anterior triangle neck lesions. CT enables the differentiation of thyroglossal duct cysts from other anterior triangle lesions based on location, CT values, and alterations in the adjacent soft tissues.

The ultrastructure of the small intestinal granule cells (GC) of the rainbow trout (Salmo gairdneri) was studied in fry and fingerlings before the cells organized to form the stratum granulosum (SG) and in 12-month-old juveniles which possess a well-developed SG several cell diameters in thickness. The GC of juvenile trout exhibit a striking reduction in nucleolar numbers and in the quantity of rough endoplasmic reticulum relative to the GC of younger fish, but contain even greater numbers of large, electron-dense cytoplasmic granules. The final stages of cellular maturation therefore take place in the GC after their organization to form a layer, and the cells appear to lose their capacity to synthesize protein(s) for the cytoplasmic granules. Since the latter structures are, nevertheless, maintained in large numbers in mature GC, it is suggested that they function intact within the cell. No precursor to the granulated form of the GC was identified in the intestine, a result which suggests that the earliest developmental stages of the GC locate within another organ.

Lesions involving the petrous apex are rarely encountered in clinical practice. This directly affects the ability of the otolaryngologist to diagnose and effectively treat these lesions. Greater physician awareness and increased technologic capability are leading to more effective management of pathologic conditions involving this area of the temporal bone.

CT is superior to other imaging modalities for detection of cervical lymphadenopathy: it is a non-invasive means of visualizing the major lymph node bearing areas in the head and neck region. Even though there are some CT observations which can be seen in both benign and malignant disease processes, correlation with history and clinical findings, and use of basic knowledge of mode of disease spread may be helpful in refining the differential diagnosis. The information obtained on CT can be used to plan the appropriate surgical approach and/or radiation ports. Additionally, CT may be used to follow the therapeutic response particularly if radiation therapy and/or chemotherapy is the method of treatment.

High-resolution CT scan is used to clearly identify the components of the innominate line. Fourteen patients with abnormal innominate lines are then examined and used to illustrate the three pathological processes affecting the innominate line, namely, destruction, hyperostosis and expansion.

Routine contrast-enhanced CT scans generally cannot exclude the presence of an acoustic neuroma of 1 cm. or less in size (1,2,3). CT — metrizamide cisternography, though excellent in defining a cisternal mass lesion, cannot be visualized intracanalicular unless the acoustic canal is grossly enlarged and therefore cannot exclude the presence of a lesion limited to canal or porus (2). Pantopaque cisternography has so far been the only neuroradiologie examination that can exclude an intracanalicular acoustic neuroma, although the study may be falsely positive in a small percentage of cases (4, 5, 6) and has a potential risk of producing adhesive arachnoiditis (7,8). The presence of pantopaque may also preclude the CT evaluation of the CP angle cistern at a future date.

During our design of a workstation for diagnostic radiology, and having studied other designs being produced either commercially or institutionally, it became evident that a number of questions existed regarding the number and physical arrangement of CT images which a radiologist likes to have during interpretation. We wished to answer the questions about number and physical arrangement, and at the same time, determine how much difference there was concerning these parameters among the subspecialty sections. We approached this problem by using different numbers and arrangements of CT scan images presented to the radiologist on film. This paper will discuss the findings of this study, and explain some of the reasons given by the radiologists for their answers. The implications for workstation designs will also be discussed.

• Computerized tomography has manifest usefulness in the roentgenologic identification of intracranial masses, and acoustic neuromas are no exception. Nonetheless, traditional roentgenographic examinations for the workup of acoustic neuromas should not yet be completely discarded in favor of this new modality. Computerized tomography scanning is an insensitive and unreliable technique for delineating the size and configuration of the internal acoustic canals. With current technology, it will not reliably show neuromas less than 1.5 cm in cross-sectional dimension. Technical artifacts may also contribute to false-negative and though rare to false-positive findings. The false-negative rate will be unacceptably high in the presence of small lesions if this technique is treated as a definitive examination rather than a screening one. Though uncommon, it may also be negative in the presence of relatively large lesions. ( Arch Otolaryngol 103:314-317, 1977)

CT is an excellent means of evaluating patients with neck masses. It has the capability of defining the precise location of a mass and its effect on adjacent structures. The information obtained on CT may be used to determine the best possible approach for biopsy or surgery and to determine radiation therapy ports.

High-resolution computerized tomography with its ability to produce excellent contrast and exquisite anatomic detail remains the primary modality in the preoperative evaluation of middle ear cholesteatomas. The radiographic findings not only support the clinical diagnosis but also determine the surgical approach. The presence of disease in areas that are difficult to evaluate, such as the sinus tympani and the anterior portion of the facial canal, can now be documented. The major contribution of MRI appears to be in defining the relationship of middle ear disease with intracranial pathology. The role of MRI in assessing focal middle ear disease awaits improved spatial resolution.

Disenchantment with the limitations, and in some cases the morbidity, of currently used radiologic techniques for the demonstration or exclusion of small acoustic neuromas prompted development of an examination using small amounts of intrathecal air and computed tomography (CT). A prospective study was designed to evaluate air CT cisternography/canalography, wherein patients with the clinical symptoms of acoustic neuroma but with negative enhanced CT, were evaluated by metrizamide CT cisternography followed by air CT cisternography/canalography. Pantopaque cisternography was then performed as a control procedure. Four patients had surgically proven tumors. In 13 others, accumulated evidence indicated no tumors were present. Results suggest that air-CT cisternography is superior to all other diagnostic methods in defining small acoustic neuromas, and may exclude an intracanalicular lesion without the potential hazards of Pantopaque cisternography or high concentration metrizamide tomocisternography. With air-CT cisternography, there were no errors in this series.

The computed tomographic (CT) scans of 44 patients who presented with nonthyroid/parathyroid lesions involving the soft tissues of the neck were analyzed. Among these patients, there were 26 with nodal masses, 6 with vascular lesions, 5 with neural lesions, and 8 with disease involving the connective tissues. One patient had both connective-tissue and vascular disease.CT allowed accurate determination of the extent of disease, while certain CT features added specificity to the diagnosis. It is concluded that CT is the procedure of choice in examining patients with neck lesions.

Sonographic images of the vocal cords were obtained in 41 healthy human subjects using a phased array realtime ultrasound scanner. The thyroid cartilage provides the acoustic window for sonographic visualization of the vocal cords. The false vocal cords appear as hyperechoic structures, while the true vocal cords are seen as hypoechoic structures. The symmetry of movement of the vocal cords during respiration becomes apparent on examination in real time. Sonography may prove to be a potentially useful technique for the examination of the vocal cords.

This article emphasizes the value of high-resolution CT scanning in evaluating the skull base. The use of axial and coronal sections, imaged at both bone and soft tissue windows, is emphasized, and a systematic approach to analysis of lesions of the skull base is offered.

Die Meridionalzirkulation. Innerhalb der Troposphare, wo, gemas den Resultaten der Strahlungsforscher, kein Strahlungsgleichgewicht vorhanden ist, mussen wir allgemein Open image in new window voraussetzen.

Das Temperaturfeld der Atmosphare nahe der Erdoberflache unterliegt sowohl den periodischen taglichen und jahreszeitlichen Schwankungen, als auch den aperiodischen Veranderungen. Wenn man diese Schwankungen durch Mittelbildung fur Zeitraume von mehreren Jahren eliminiert, bekommt man ein ziemlich einfaches Bild des mittleren Temperaturfeldes der Luft im Meeresniveaul (Abb. 98 und 99). Die Isothermen umschliesen beide Pole, in deren Nahe die kaltesten bodennahen Luftschichten sich befinden. Am warmsten sind die bodennahen Luftschichten in dem Aquatorialgurtel, und zwar lagern die allerwarmsten Teile derselben uber den aquatorialen Landflachen.