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A general scenario of Hox gene inventory variation among major sarcopterygian lineages
Dan Liang, Riga Wu, Jie Geng, Chaolin Wang, Peng Zhang
BMC Evolutionary Biology , 2011, DOI: 10.1186/1471-2148-11-25
Abstract: We determined the Hox gene inventory for six sarcopterygian groups: lungfishes, caecilians, salamanders, snakes, turtles and crocodiles by comprehensive PCR survey and genome walking. Variable Hox genes in each of the six sarcopterygian group representatives, compared to the human Hox gene inventory, were further validated for their presence/absence by PCR survey in a number of related species representing a broad evolutionary coverage of the group. Turtles, crocodiles, birds and placental mammals possess the same 39 Hox genes. HoxD12 is absent in snakes, amphibians and probably lungfishes. HoxB13 is lost in frogs and caecilians. Lobe-finned fishes, amphibians and squamate reptiles possess HoxC3. HoxC1 is only present in caecilians and lobe-finned fishes. Similar to coelacanths, lungfishes also possess HoxA14, which is only found in lobe-finned fishes to date. Our Hox gene variation data favor the lungfish-tetrapod, turtle-archosaur and frog-salamander relationships and imply that the loss of HoxD12 is not directly related to digit reduction.Our newly determined Hox inventory data provide a more complete scenario for evolutionary dynamics of Hox genes along the sarcopterygian lineage. Limbless, worm-like caecilians and snakes possess similar Hox gene inventories to animals with less derived body morphology, suggesting changes to their body morphology are likely due to other modifications rather than changes to Hox gene numbers. Furthermore, our results provide basis for future sequencing of the entire Hox clusters of these animals.The Hox genes are a large family of homeobox-containing transcription factors that control morphologies on the body axis of nearly all metazoans. Most of Hox genes normally consist of two exons with the conserved 180-bp homeobox located in exon2. In many animal species, Hox genes are arranged in genomic clusters with up to 15 distinct gene members [1] and, importantly, they are expressed in a "collinear fashion" -- anterior genes are expre
Pulsars: Gigantic Nuclei  [PDF]
Renxin Xu
Physics , 2011, DOI: 10.1142/S0218301311040190
Abstract: What is the real nature of pulsars? This is essentially a question of the fundamental strong interaction between quarks at low-energy scale and hence of the non-perturbative quantum chromo-dynamics, the solution of which would certainly be meaningful for us to understand one of the seven millennium prize problems (i.e., "Yang-Mills Theory") named by the Clay Mathematical Institute. After a historical note, it is argued here that a pulsar is very similar to an extremely big nucleus, but is a little bit different from the {\em gigantic nucleus} speculated 80 years ago by L. Landau. The paper demonstrates the similarity between pulsars and gigantic nuclei from both points of view: the different manifestations of compact stars and the general behavior of the strong interaction.
Multiple gigantic renal cysts
?ivkovi? Sla?ana,Pavlovi? Svetlana,?iri? Slobodan
Vojnosanitetski Pregled , 2009, DOI: 10.2298/vsp0902163z
Abstract: Introduction. Cystic renal lesions are very heterogeneous lesions which differ in ethiopathogenesis, morphological and clinical manifestations, and also in evolution and therapy. Classification of cystic lesions is complex, symptomatology is poor, and diagnosis is based on complete radiological diagnostic procedures. Case report. We presented a 20-year old patient with mild subjective symptoms. Objectively, he was without positive clinical signs and changes in biochemistry of blood. Using ultrasonography (US) multiple serous simple cysts were found in both kidneys. Using computed tomography (CT) multiple serous cysts were found, without changes in cystic walls, with preserved renal parenchyma and without cystic changes on other parenchymatous organs. Conclusion. Although renal cystic lesions are frequent in adult population, this is a rare example of a young adult man with simple, gigantic, serous cysts which do not produce clinical manifestations nor functional renal difficulty so far.
Investigation of initiation of gigantic jets connecting thunderclouds to the ionosphere  [PDF]
Lizhu Tong,Kenichi Nanbu,Hiroshi Fukunishi
Physics , 2004,
Abstract: The initiation of giant electrical discharges called as "gigantic jets" connecting thunderclouds to the ionosphere is investigated by numerical simulation method in this paper. Using similarity relations, the triggering conditions of streamer formation in laboratory situations are extended to form a criterion of initiation of gigantic jets. The energy source causing a gigantic jet is considered due to the quasi-electrostatic field generated by thunderclouds. The electron dynamics from ionization threshold to streamer initiation are simulated by the Monte Carlo technique. It is found that gigantic jets are initiated at a height of ~18-24 km. This is in agreement with the observations. The method presented in this paper could be also applied to the analysis of the initiation of other discharges such as blue jets and red sprites.
A COMPARISON OF HEAT TRANSFER AROUND A SINGLE SERRATED FINNED TUBE AND A PLAIN FINNED TUBE
S.R.Mcilwain
International Journal of Research and Reviews in Applied Sciences , 2010,
Abstract: With comparable bundle geometry, serrated fin finned tube heat exchangers transfer more heat than plain finned ones. There are believed to be many factors in this behaviour, and this investigation used CFD to examine the heat transfer and fluid flow patterns around the fins to try to understand the magnitude of the differences in the processes. The study is a first step in developing a new theory-based method to predict the performance of serrated fin tube bundles.
Surgery of gigantic infrarenal aneurysm of abdominal aorta
E. Solakovi?,H. Vrani?,A. Had?imehmedagi?,I. Arslani
Medicinski Glasnik , 2005,
Abstract: The case shows gigantic aneurysm of abdominal aorta, localized infrarenally, as well as aneurysms of bilateral iliac arteries, which were solved successfully by resection of aneurism of abdominal aorta, closure of iliac arteries near aortic bifurcation, and interposition of aorta-bifemural vascular graft. There were no postoperative complications,and final outcome was fully satisfactory.
Gigantic enhancement of spin Seebeck effect by phonon drag  [PDF]
Hiroto Adachi,Ken-ichi Uchida,Eiji Saitoh,Jun-ichiro Ohe,Saburo Takahashi,Sadamichi Maekawa
Physics , 2010, DOI: 10.1063/1.3529944
Abstract: We investigate both theoretically and experimentally a gigantic enhancement of the spin Seebeck effect in a prototypical magnet LaY$_2$Fe$_5$O$_{12}$ at low temperatures. Our theoretical analysis sheds light on the important role of phonons; the spin Seebeck effect is enormously enhanced by nonequilibrium phonons that drag the low-lying spin excitations. We further argue that this scenario gives a clue to understand the observation of the spin Seebeck effect that is unaccompanied by a global spin current, and predict that the substrate condition affects the observed signal.
Numerical Analysis of Mixed Convection through an Internally Finned Tube  [PDF]
Sachindra Kumar Rout,Dipti Prasad Mishra,Dhirendra Nath Thatoi,Asit Ku. Acharya
Advances in Mechanical Engineering , 2012, DOI: 10.1155/2012/918342
Abstract: Wall temperature of an internally finned tube has been computed numerically for different fin number, height, and shape by solving conservation equations of mass, momentum, and energy using Fluent 12.1 for a steady and laminar flow of fluid inside a tube under mixed flow condition. It has been found that there exists an optimum number for fins to keep the pipe wall temperature at a minimum. The fin height has an optimum value beyond which the wall temperature becomes insensitive to fin height. For a horizontal tube, under mixed flow condition, it is seen that the upper surface has higher average temperature than the lower surface. The impact of fin shape on the heat transfer rate shows that wall temperature is least for triangular-shaped fins, compared to rectangular- and T-shaped fins. In addition to the thermal characteristics, the pressure drop caused due to the presence of fins has also been studied. 1. Introduction Laminar mixed convection and conduction across a heated finned tube has practical implications. Internally finned tubes are commonly used in engineering applications as effective and efficient means to improve convective heat transfer in compact heat exchangers. In the light of recent economic and environmental concerns, researchers are aggressively looking for new methods of heat transfer control both in external-finned and internal-finned heat exchangers. Internally finned tubes perform differently depending on whether the flow is laminar or turbulent. Laminar flow heat transfer in tubes finds wide engineering applications in many practical fields which include heating or cooling of viscous liquids in the process industries, heating or cooling of oils, heating of circulating fluid in solar collectors, and heat transfer in compact heat exchangers. For laminar flow and heat transfer, comprehensive experimental and numerical investigations have been performed for variable fluid properties, mixed convection, and fin geometry. Heat transfer augmentation techniques play a vital role here since heat transfer coefficients are generally low for laminar flow in plain tubes. Designing a tubular heat exchanger with fins having different shapes and sizes is one such augmentation technique discussed in this paper. When an array of fins is used to enhance heat transfer, the prime focus is to optimise geometry of fins which will maximise the heat transfer rate under space and cost constraints. The heat transfer to the fluid flowing through a finned tube by the heat dissipating surfaces can be obtained mainly by using the mechanisms of heat transfer by
Gigantic tongue lipoma: A case report
Mapfumo Chidzonga,Midion; Mahomva,Leonard; Marimo,Clemence;
Medicina Oral, Patología Oral y Cirugía Bucal (Internet) , 2006,
Abstract: lipomas are among the most common tumors of the human body. however, they are uncommon in the oral cavity. in the oral cavity they present as a slow growing, painless, and assymptomatic yellowish submucosal mass. surgical excision is the treatment of choice with recurrence not expected. they have been known to grow to large sizes causing mastication and speech difficulties. the usual lesions consist of a well circumscribed, lobulated mass of mature fat cells. in other situations the covering mucosa becomes ulcerated and presents difficulties in diagnosis. the present report is of a patient who presented with a gigantic lipoma on the tip of the tongue which had been present for 3 years. she now had difficulty with speech and mastication as the tongue tumor now completely filled the oral cavity. an incision biopsy confirmed the tumor as lipoma. the tumor was surgically excised with restoration of normal tongue function, speech and masticatory capacity. histopathologic examination of the excised tumor confirmed that it was a lipoma.
A rare gigantic solitary cysticercosis pseudotumour of the neck
Seif J Uledi
Journal of Surgical Case Reports , 2010,
Abstract: Cysticercosis is one of the ancient parasitic infections and endemic in many parts of the developing world. Humans acquire cysticercosis when they ingest pork tapeworm eggs either through faecal-oral route by eating faecally contaminated food or by auto infection.The clinical picture largely depends on the location of larval encystment. Neurocysticercosis is the most common form of presentation. Solitary extra neural lesions are quite rare and fairly small in size.We present a very unique case of 56 year old Malawian female with a very rare, long standing gigantic solitary cysticercosis pseudo tumour of the neck. By far, there is no documented report on incorrigible cysticercosis lesion with such a sheer size.Solitary extraneural cysticercosis lesions may mimic other soft tissue masses; therefore it is important for clinicians working in endemic regions to consider cysticercosis as a differential diagnosis when evaluating patients with soft tissue lesions.
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