Concave Border Research Articles

On the occurrence of Carentonosaurus Rage and Néraudeau, 2004 (Squamata, Pythonomorpha) in the Iberian Cretaceous, with description of a new species from the uppermost middle Cenomanian of West Portugal

Several vertebrae were recently collected in paralic facies with fossil assemblages of late middle Cenomanian age, outcropping in the basal carbonate platform sequence of Casais dos Carecos, near Coimbra (West Portugal). These fossil remains are exceptionally well preserved, with fragile elements still present. They correspond to cervical and dorsal vertebrae, including a juvenile cervical vertebra. The general morphology, features and size of the dorsal vertebrae are close to those described and figured for the holotype of Carentonosaurus mineaui Rage and Néraudeau, 2004, but showing distinct lateral and subcentral foramina, neural spine with longitudinal grooves and displaying a sagittal furrow along the ventral surface, which are absent in this genotype. The centrum shows a subtriangular shape in ventral view, with concave borders. These different morphological features of the fossil remains here presented allow the description of Carentonosaurus soaresi sp. nov. This new material improves the knowledge of the representatives of Carentonosaurus and extends the biogeographical distribution of this genus of Pythonomorpha to the western margin of the Iberian Peninsula.

Gross morphological and surface ultrastructural investigation on the gills of the European barracuda Sphyraena sphyraena.

The present work examined 10 gill systems of European barracuda grossly and by scanning electron microscopy (SEM). Grossly, there were four pairs of the gill arches. The convex border of the gill arch carried the gills filaments, but there were abundance of spines near to its concave border and the gill rakers were absent. Laterally near to the convex border of the gill arch, SEM observations revealed that the first gill arch carried small elliptical, oval, cuboidal, and triangular groups of two shapes of spines; spearhead-like spines and canine-like spines, but the other three gill arches carried larger groups of the same shaped spines with the appearance of waterfalls. Medially near to the convex border of the first gill arch, the canine-like spines were observed only in the form of vertical rectangular groups that adhered in some areas. Laterally near to the concave border, the two shapes of spines were present in the form of longitudinal groups separated by spaces at the first gill arch, but these spaces were absent in the other three gill arches. Medially near to the concave border of the first gill arch, the two shapes of spines were presented in oval groups, while the other three gill arches were covered entirely by cuboidal groups of the two shapes of spines. The absence of the gill rakers in conjunction with an abundance of spines helps the European barracuda to control the food particles from escaping to the gill filaments to prevent its suffocation.

Two species of Tsinania (Trilobita, Corynexochida) from upper Furongian (Cambrian) of northern Anhui, China and their intraspecific variation

Hundreds of specimens of the trilobite Tsinania were collected from the Cambrian (upper Jiangshanian through Stage 10) at Fenghuangshan in northern Anhui, China, and were identified as Tsinania canens (Walcott, 1905) and Tsinania dolichocephala (Kobayashi, 1933). Comparisons between these two species and others referred to Tsinania, allow the redefinition of the two species. Fourteen synonyms and thirteen synonyms have been incorporated into T. canens and T. dolichocephala respectively. The key diagnosis of T. canens includes: the preglabellar field is flat, relatively short (sag.), has a slightly to obviously angular anterior margin; pygidium is rounded triangular and strongly convex; pygidial border is absent or very narrow. The key diagnosis of Tsinania dolichocephala comprises: the glabella is moderately convex with flat anterior part and convex posterior part (sag.); anterior border is relatively long (sag.), rounded to sharply angulated; pygidium is rounded triangularly with a wide, concave border. Upon such diagnoses, the potential intraspecific variations (e.g., the angularity of the anterior margin, the triangularity of the pygidium, and the width of the pygidial border) of the two species are discussed and listed. The late ontogeny of both species is described to further support the intraspecific variations.

Morphological studies on the gills of the European hake (Merluccius merluccius, Linnaeus, 1758).

The current work gives concern to study the morphology of the Merluccius merluccius gills by using gross morphology, scanning electron microscopy (SEM), and light microscopy. The findings of the present study revealed that the gill system consisted of four pairs of gill arches which carry the gill filaments on the convex border and gill rakers on the concave border of them. SEM results revealed that the rakers and the spines distribution on the first gill arch differed from that of the other three gill arches on the lateral and medial surfaces. On the surface the gill filaments, there were longitudinal ridges that carried pores of chloride cells and mucous cells. The histological examination revealed that, the gill arch composed of hyaline cartilage that presented in the form of cups. Each cup consisted of central cartilagenous core and peripheral cartilagenous matrix. The gill filaments composed of cartilaginous bar of peripheral cartilaginous matrix and central cartilaginous core extended from the gill arches and covered by an epithelial layers with a few mucous cells permeate it, and chloride cells were straggly in the interlamellar epithelium. Each gill filament carried several leaves like secondary lamellae on both sides of it. The epithelium, which lined the secondary lamellae, composed of epithelial pavement cells, some mucous cells, and pillar cells.

Morphological variation in the anterior cranial fossa.

The anterior cranial fossa is an important anatomical landmark in clinical orthodontics consisting of the frontal, ethmoid, and sphenoid bones. The relationships between these bones remain poorly understood. The purposes of the present study were to describe the morphological relationships among the three bones and to discuss the factors contributing to individual variations in adult skulls based on postnatal development. Skulls of 100 Indian adults and 18 Japanese juveniles were observed both macroscopically and using computed tomography images in the median sagittal plane. Three types of relationship were seen among the three bones in adult skulls: (a) a triangular border between ethmoid and sphenoid bones (ethmoid spine), (b) a straight or concave border between ethmoid and sphenoid bones, and (c) frontal bone lying between the ethmoid and sphenoid bones. In the juvenile skull, structures corresponding to those in adults were observed. These three bones comprise the anterior cranial base, each with differing developmental processes, and slight differences in these processes seem to be reflected in the morphological variations seen among adults.

Ultrastructure features of the surface of the gills and the lower pharyngeal jaw of the Tilapia Zilli, redbelly tilapia (Coptodon Zillii, Gervais, 1848).

The present investigation was designed to describe the surface ultrastructure of the gill system of tilapia Zilli. The gill system is formed from four gill arches and each gill arch carries a row of gill filaments on its convex border and two rows of the gill rakers on its concave border. The quadrilateral interbranchial septum has elevated part at the level of the third gill arch. By SEM observations, the gill arch was divided into three regions: rostral, middle and caudal region. The caudal region contained two characteristic structures: oval leaf-like structure and rounded-shaped structure. Each oval leaf-like structure carried two lateral rows of the triangular pointed spines separated by a median groove. All surfaces of gill arches, rakers and filaments were covered with a mosaic of the polygonal pavement cells, in addition to the opening of chloride cells and mucous cells. The gill arch and gill raker had only one appearance of taste buds named type I. Meanwhile, the filaments contained two types of different appearance of the taste buds named: type I and type II. Type I was the main common and similar to that present in gill arch and raker and characterized by its blunt end, while type II had hair-like structures that projected from the volcano-shaped depression. The gill rakers were formed from central axis surrounded by two lateral lobulated regions which carry pointed spines, taste buds and the opening of chloride cells. The surface of triangular lower pharyngeal jaw carries numerous teeth-like papillae which originated from the socket-like depression.

Comparative studies on the gill rakers of some marine fishes with different feeding habits

The present study aimed to compare between gill rakers of some marine fishes with different feeding habits. A total of 78 specimens in 13 species belonged to 6 fish families: Sparidae (Sparus aurata, Diplodus noct, Rhapdosargus haffara and Boops boops); Family: Mugilidae (Mugil cephalus, Mugil capito and Liza aurata); Family: Siganidae (Siganus rivulatus and Siganus luridus); Family: Synodontidae (Saurida undosquamis and Synodus saurus); Family: Clupeidae (Herklotsichthys quadrimaculatus) and Family: Carangidae (Caranx sexfasciatus) were collected by irregular visits from land fish market in different localities of Egyptian Mediterranean Sea and Suez Gulf; during the period from March, 2014 to November, 2014. Results showed that, the first gill arch formed of one piece, consisting of two limbs (upper and lower limbs). The gill arch carried two rows of gill rakers on its concave border and two rows of gill filaments on its convex one. The gill rakers in the anterior row (oral row) are longer, more in number and more developed than that of the posterior row (aboral row). The gill arch in family Sparidae is bow-like shape. The anterior gill rakers on the first gill arch of most sparid species are short, conical in shape adapted to carnivorous feeding. The gill arch of fish species in Mugilidae is mostly crescent-shaped and rarely bow-shaped. The anterior gill rakers on the first gill arch are long and great in number adapted to detritus feeding. The gill arch in family Synodontidae is V shaped. The anterior gill rakers on the first gill arch appeared as clusters of small tooth patches adapted to piscivores feeding. The gill arch in family Siganidae is hook-like shape. The anterior gill rakers on the first gill arch were needle spine in shape with secondary projections adapted to herbivorous feeding. The gill arch in fish species of Clupeidae is V like shape. Gill rakers are well developed and arranged in only one row. They are numerous and elongated adapted to seizing food items in the plankton feeding. The gill arch in fish species of Carangidae is bow-like shape. Gill rakers are moderate in length and number adapted to carnivorous feeding. According to the different feeding habits, the results showed that, the highest average length of the first gill arch (mm) is recorded in carnivore and piscivore fish. The maximum averages number and the length of the anterior gill rakers are recorded in detritivore fish and plankitivore fish. The highest percentages of the anterior gill raker length /gill arch length ratio (%) are recorded in plankitivore fish and detritivore fish. Results showed that, the maximum inter raker space (µm) and the inter raker space/gill arch length (%) is recorded in carnivore fish. The maximum breadth at the raker base (µm) in the anterior row of rakers is recorded in piscivore fish. The highest breadth at the raker base/gill arch length (%) in the anterior row of rakers is recorded in carnivore, piscivore and planktivore fish. The highest posterior gill raker length (µm) and the posterior gill raker length /gill arch length ratio (%) are recorded in detritivore fish. In conclusion: The morphological characters of the gill rakers in the first gill arch were differ in species studied according to different feeding habits. So that, can be used in determine the fish family and feeding habits.

The braincase of Chanaresuchus ischigualastensis (Archosauriformes) from the Late Triassic of Argentina

ABSTRACT Here, we present information regarding the braincase anatomy of Chanaresuchus ischigualastensis, from the Ischigualasto Formation (Carnian) of Argentina. The braincase is very similar to that previously described for Chanaresuchus bonapartei, but bears some differences: rostral contour of the basal tubera nearly transversely oriented in ventral view; basal tubera with rounded distal tips in ventral view; paroccipital processes with a slight distal widening in caudal view; sulcus on the caudal surface of each paroccipital process restricted to the proximal two-thirds of the latter; and parabasisphenoidal ventral surface transversely concave. A phylogenetic analysis was performed using exclusively neurocranial characters, including a few new characters, to investigate phylogenetic hypotheses suggested by the neurocranial evidence. The neurocranial data support a sister-group relationship between Chanaresuchus ischigualastensis and C. bonapartei, on the basis of the presence of an intertuberal plate with a concave border. Our analysis also suggests the monophyly of a group formed by both species of Chanaresuchus and Proterochampsa. This group was supported by one apomorphy: the paroccipital processes are elongated relative to their height, which did not show homoplasy in our results. Our results show that Doswellia is the sister group of the clade formed by these proterochampsids, supporting inclusion of the former within the Proterochampsia, and this clade is recovered as more closely related to archosaurs than to Euparkeria.

Génesis de la estructura arqueada de la Sierra de las Cabras al Gibalto (Subbético, provincias de Málaga y Granada, España)

The Subbetic sierras of Las Cabras to the Gibalto form an arched structure, giving it a high relief, constituted by many tectonic slices, verging to the South in its southern border and to the North and West in its concave border. Although it could be interpreted as an allochthonous structure, really is rooted in the transitional area between the Median and the Internal Subbetic. Several local factors have influenced this complex structure, but the final cause is the oblique collision (transpression) of the In-ternal Zone against External Zone of the Betic Chain, producing an important strike-slip system.

Renal Sinus Adiposity and Hypertension

Obesity, a global health problem, has an ever increasing prevalence.1 Because excess weight is a major risk factor for high blood pressure, this results in a continuous rise in the prevalence of hypertension.2 In this issue of Hypertension , Chughtai et al3 identified a potential pathogenic link between renal sinus adiposity and hypertension in humans. Adipose tissue can be divided into compartments that carry a different metabolic risk. Thoracic and intra-abdominal adipose tissue have a strong relation with hypertension,4 whereas subcutaneous and thigh intermuscular fat tissue seem less important.5,6 Chughtai et al3 assessed the relation between the amount of renal sinus fat and hypertension. The renal sinus is the cavity within the concave border of the kidney. Other than fat, this sinus is composed of renal vessels, calices, nerve tissue, and lymphatic channels. In middle-aged and elderly individuals at risk for cardiovascular events (N=205), Chughtai et al3 showed a quantitative relation between renal sinus fat, measured …

Bartonaspis new genus, a trilobite species complex from the base of the Upper Cambrian Sunwaptan Stage in North America

Despite being reported widely from basal Sunwaptan strata, Dellea? punctata Palmer, 1965, is known from only four figured cranidia. New material from Nevada, Utah and Oklahoma, including librigenae and pygidia, indicate that specimens assigned previously to D.? punctata are best interpreted as a complex of related species that are assigned to a new genus, Bartonaspis. This genus is diagnosed by punctate sculpture, a pair of fossulae at the anterior corners of the glabella, and by a subelliptical pygidium with a short convex axis composed of three segments. Three new species, B. fredericksoni, B. palmeri, and B. wilsoni, are described and B. punctata (Palmer) is restricted to its holotype. Bartonaspis is known only from the Irvingella major Zone, and its first appearance defines the base of the Sunwaptan Stage. Dellea Wilson, 1949, is related to Bartonaspis and is differentiated from it primarily by pygidial morphology. In contrast to Bartonaspis, the pygidium of Dellea has an axis composed of four, rather than three, segments and a narrow concave border.

Maxwell’s demon as a dynamical model

We consider a model of a billiard-type system, which consists of two chambers connected through a hole. One chamber has a circle-shaped scatterer inside (Sinai billiard with infinite horizon), and the other one has a Cassini oval with a concave border. The phase space of the Cassini billiard contains islands, and its parameters are taken in such a way as to produce a self-similar island hierarchy. Poincar\'e recurrences to the left and to the right chambers are considered. It is shown that the corresponding distribution function does not reach ``equipartition'' even during the time ${10}^{10}$. The explanation is based on the existence of singularities in the phase space, which induces anomalous kinetics. The analogy to the Maxwell's Demon model is discussed.

Origin of placer gold nuggets and history of formation of glacial gold placers, Gold Creek, Granite County, Montana

Placer gold along the upper portions of Gold Creek, near Deer Lodge, Montana, occurs in Pliocene(?) fossil alluvial placers, Pleistocene till, and alluvium. The upper Gold Creek placers yielded an estimated 175 to 200 kg gold during 1890 to 1990. The gold probably originated in veins, skarn, or replacement deposits in Paleozoic and Mesozoic sedimentary units near the contact with Late Cretaceous granodiorite of the Royal stock. Gold was initially concentrated in alluvial placers along the ancestral Gold Creek valley during late Tertiary (Pliocene) time. Pleistocene glaciers scoured the Pliocene placers from most parts of the valley, although the fossil placers were locally buried beneath till and gold was also incorporated into till that was deposited farther down valley. Gold from Pliocene and Pleistocene placers has locally been reconcentrated into alluvium as a result of postglacial stream incision.The placer gold occurs as coarse-sized, oval to elongate grains characterized by rounded protuberances and inclusions of quartz and sulfide minerals. In polished section the grains have alternating convex and concave borders interrupted by pits and embayments. Grain borders and interiors of embayments display supergene gold rims averaging 98.8 percent Au. Microprobe analysis of cores indicate average compositions of 83.6 percent Au and 16.5 percent Ag and spectrographic data indicate a trace element signature enriched in Cu, Pb, and Sb, which is compatible with derivation from mesothermal plutonic lode deposits associated with the Royal stock.

Distribution of filamentous actin in and around spermatids and in spermatozoa of Australian conilurine rodents

The distribution of filamentous actin around the maturing sperm head and in spermatozoa of four species of Australian conilurine rodents was investigated at the light and electron microscopic levels. Similar results were obtained for all the species studied. Mechanically isolated spermatids had NBD-phallacidin-positive longitudinal bands of fluorescence over the dorsolateral surface and, in late spermatids, bands of bright fluorescence passed perpendicularly from the dorsal convex to ventral concave surface. TEM observations indicated that these regions corresponded to filaments of ectoplasmic specializations and granular filamentous material around the tubulobulbar complexes, respectively. In testicular and cauda spermatozoa NBD-phallacidin fluorescent material was present in the two ventral processes that extended from the upper concave surface of the sperm head; also fainter material occurred along the concave border and as a dorsocaudal spur. Its distribution was identical for testicular and cauda spermatozoa. TEM of late spermatids showed that in the ventral process closest to the apical hook there were between 170 and 245 filaments, which attached to the inner surface of the postacrosomal dense lamina; in the more caudal ventral process about 70 filaments occurred. No filaments were, however, visible in the mature spermatozoon but, after immunocytochemical labelling for actin, deposition of gold particles was evident over ventral processes of both late spermatids and cauda spermatozoa. Within the female tract these ventral processes made contact with the zona matrix and were taken into the egg cytoplasm unchanged in morphology. The possible functional significance of the filamentous actin in these structures is discussed.

Optimization of conformal radiotherapy dose distributions by simulated annealing: II. Inclusion of scatter in the 2D technique

For pt.1 see ibid., vol.34, p.1349-69 (1989). Part 1 used the simulated annealing optimization method to deduce the beam profiles and showed how target areas with concave borders, containing organs at risk, could be achieved for a variety of clinical problems posed in the literature. In order to establish the method a simple 'primary-only' beam model was used. The author now reports further developments with this treatment planning technique to include scattered radiation. An extension of the method into three dimensions has also recently been completed (Webb, 1990,1991).

Sonography of adrenal glands in neonates and children: changes in appearance with age.

The sonographic appearance of the normal adrenal gland in children varies with age. In newborns, the cortex is large and hypoechoic, whereas the medulla is relatively small and hyperechoic. With increasing age, the cortex becomes smaller and the medulla relatively larger. The cortex remains hypoechoic and the medulla hyperechoic until age 5-6 months, by which time the gland has become hyperechoic and smaller, with poor or absent sonographic differentiation between cortex and medulla. After 1 year of age, the appearance of the gland is similar to that of the adult gland, with straight or concave borders and a hypoechoic character.

Communicating enterogenous cyst of duodenum receiving the termination of the common bile duct demonstrated by intravenous cholangiography.

Enterogenous cysts are developmental defects of gut which may arise anywhere in the gastrointestinal tract but are rare in the duodenum. The embryological mechanism is probably the failure of complete coalesence of fetal vacuoles of the .primitive gut. They may communicate with the bowel lumen and may receive the bile and pancreatic ducts. Sex distribution is equal; one third of the cases are in adults (1, 3, 4). The symptoms are usually those of duodenal obstruction, but ulceration, bleeding, jaundice, and pancreatitis may occur (8, 9). The most common physical finding is a movable, non-tender mass in the right epigastrium where a fluid-density mass may be seen on radiographs. A sharply defined mass attached to the concave border of the duodenum is typically observed on barium study. It is usually not possible to differentiate the lesion from lipoma, leiomyoma, aberrant pancreas, or other intramural tumefactions that also occur in this area (2, 3, 6). Case Report This 14-year-old Caucasian female became ...

Acute pancreatitus due to a peri-vaterine.

The occurrence of acute pancreatitis due to obstruction of the pancreatic ducts by a duodenal peri-Vaterine diverticulum is very unusual. Edwards,^1,2in 1939, stated that there was no authentic autopsy description of pancreatitis caused by the pressure of a diverticulum of the duodenum on the pancreatic duct. Ogilvie,³in his review, cited five such cases from the literature and added three of his own. The English and American literature is lacking in specific reports of this entity from 1941 through 1957. Hoffman,⁴Cattell and Mudge,⁵and Warren and Emery⁶listed acute pancreatitis as a complication of duodenal diverticula. The second portion of the duodenum is the portion which most frequently contains diverticula (66% of the cases).⁴Most of these present on the medial concave border of the duodenum and protrude into the pancreatic tissue. Duodenal diverticula, as well as acute pancreatitis, can occur in

XX.— Two New Trilobites from Girvan

The purpose of this short paper is to put on record 2 new species of trilobites from the Ashgillian rocks of Girvan. The specimens were found by the writer and the new Proetid is described by him. The new Illaenid has been described by Dr. Reed of Cambridge who has contributed so extensively to our knowledge of the fauna of the Lower Palaeozoic rocks of the Girvan District. The new Proetus comes from the ‘Upper Starfish Bed’ (Bed No. 2), which is 18 inches higher than the older well-known “Starfish Bed” (Bed No. 1) in the Drummuck Group of Lady Burn. This upper bed has yielded 5 new species of Proetus none of which has been found in the lower bed. The new Illaenus is from the lower bed (No. 1) and as will be seen in Plate 1, figs. 3, 4, the anterior margin of the doublure or reflexed border is composed of three curves, a feature which has been found in other Illaenids from the same horizon ( I. longicapitatus, I. fluvialis and? I. cf. avus ). J.L.B. Description of Species. Illaenus drummuckensis sp. nov. Plate 1, figs. 3, 4. Pygidium elongate, semioval, gently convex, most so transversely. Axial lobe indistinctly defined, nearly half the length of the pygidium, with slight independent convexity anteriorly, and projecting considerably beyond the anterior margin, more than one third the width of the pygidium. Pleural lobes gently arching down to undefined slightly concave border; short straight anterior edge; fulcrum at about one-third the width This 250-word extract was created in the absence of an abstract

Roentgen Manifestations of Acute Infectious Mononucleosis in the Abdomen

Acute mononucleosis or acute glandular fever is an infectious disease characterized by fever, lymphadenopathy, a mononucleosis, and an increased titer for sheep cell agglutinins. Pfeiffer in 1889 described an epidemic disease of children which he called “Drusenfieber,” characterized by fever and enlargement and tenderness of the cervical lymph nodes. In 1922 Longcope described a syndrome closely related to the one described by Pfeiffer and, because of the associated mononucleosis, recommended the term “infectious mononucleosis,” which Sprunt and Evans had previously suggested. Acute mononucleosis occurs mainly in children and young adults, and is believed to be contagious, but no causative agent bas been definitely isolated. Some believe it to be a fusospirochetal infection. Sectioned lymph nodes show hyperplasia of the lymphoid tissue. The spleen may become palpable and tender. The unusual features of the disease are the mononuclear leukocytosis with an absolute reduction in the number of polynuclear granular cells to from 2,000 to 4,000 per cu. mm., and the specific agglutination test (heterophile test) which is practically pathognomonic in high titers, especially if no serum has previously been administered to the patient. The term “heterophile” was applied by Landsteiner to reactions of antibodies with antigens which are not related in their origin, and was based on the Forssman principle, i.e., the existence of serological relationships between substances in the cells of animals widely separated in the zoological system. Abdominal symptoms in acute mononucleosis are not unusual, and an occasional case has been reported in which they have been predominant. The following case, in which we think lymphadenopathy was demonstrated roentgenographically, was of purely abdominal type. Case Report A male nurse, twenty years of age, presented himself for treatment on Aug. 17, 1939, with a history of diarrhea and diffuse pains in the upper abdomen for three days. Physical examination showed a soft, flat abdomen with slight deep tenderness in the upper quadrants. A blood count showed a total of 5,900 white cells per cu. mm., with a normal differential count, in which the mononuclear cells amounted to 1 per cent. Under routine treatment the diarrhea ceased, but the pain persisted. Gastro-intestinal roentgen studies, on Sept. 5, showed no intrinsic lesion of the stomach or duodenum. There was a slight “ironing out” of the rugae along the inner concave border of the descending duodenum with slight displacement of this part of the duodenum toward the right and posteriorly, suggestive of a space-occupying mass in the region of the pancreatic head. Extrinsic pressure defects were evident on the inferior aspect of the left half of the transverse colon, due to a lobulated mass.