Whether you are a long and lanky seasoned swimmer or short and muscular newbie or any combination of the two at some point, you want to increase your speed in the water. Swimming offers one of the best total body workouts. It’s also an excellent cross training exercise. Because the whole body is involved, however, many techniques offer opportunities to become a faster swimmer.
Commit to Workouts
Olympic swimmer and Masters swim coach Whitney Hedgepeth recommends a minimum of three to four swim workouts each week. Any less and your progress will either plateau or reverse. Alternate early morning workouts with afternoon or evening workouts. See which time feels best for you some people find it difficult to wake up to swim. If working out at the end of the day suits your schedule, don’t jump into a cold pool first thing in the morning. Find the time that suits your schedule so you can commit to regular swim workouts.
Focus on Technique
New research, highlighted in "The New York Times" in July 2012, shows that, contrary to long held beliefs of elite swim coaches and athletes, a deep catch stroke creates more lift and propulsion than the traditional sculling motion. Swimmers typically have been coached to make an S shape with their arms during the underwater, or catch, phase of their freestyle. Scientists now know that this motion actually creates drag and slows forward movement. A single long and deep catch creates the added lift a swimmer needs to increase speed.
Strength Training Out Of The Water
A deep catch stroke requires more arm, back and shoulder strength than a sculling stroke because the arms have more water to move. USA Swimming recommends a total body strength routine two to three times per week, however, to prevent muscle imbalance and avoid overtaxing upper body muscles already so heavily relied upon in the pool. Low weight, high rep circuit workouts are a good option.
Use Your Flip Turns
Don waste valuable seconds on the wall; just flip. Olympian Hedgepeth says flip turns are tantamount to speed. If you don already do flip turns, practice somersaults in the middle of the pool. Focus on tucking your knees to your chest as tight as possible. When you are ready to flip on the wall, swim until you are about one stroke away, tuck, flip and push off. If you already do flip turns, make them faster. Planks and crunches strengthen abdominal muscles. Jump squats and lunges strengthen legs, hips and buttocks. A hardier core and stronger legs mean less time on the walls.
A tight streamline off the flip turn also increases speed. Don let your shoulders sag and your elbows bend. Instead, flip, push off, and be extremely mindful of straightening your arms behind your head, making your body as long as possible, like a bullet. With practice, efficient streamline becomes second nature.
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The cover of this month’s issue of Golf Digest features LPGA tour golfer Lexi Thompson wearing a golf towel? Cut up shirt? Weird scarf? and not much else. It’s the "Fitness Power Issue," which I guess has something to do with side boob. I Twerked My Boobs to Mozart.
50Tommy Craggs shared a post by Sara X MillsMy name is Sara, but by now you might better know me as "the Mozart boob twerk girl" from sites all over the internet, including this one. A week ago exactly, I was sitting where I am now, editing a video I had no idea would garner over 21 million views worldwide in seven days. She is a 6 foot 7 dancer who is best known for touring with Miley Cyrus, but she is also known for other things. One of those things happens to be taking boobsy photos with various NBA players mostly Blake Griffin. It began with a Brazilian soccer fan bringing the "fuck her right in the pussy" fake news blooper to life, and it ended with a very happy/drunk World Pride attendee shaking her boobs right at the camera during a live on the scene report. I made an offhand comment about an acquaintance who’d once worked as a bikini barista. I might as well have said she’d once worked as a frog. Janet Jackson’s "wardrobe malfunction" was why the few subsequent Super Bowl halftime shows were safe, old, boobless acts like Paul McCartney and Bruce Springsteen.
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The Nedd4 family of E3 ubiquitin ligases: functional diversity within a common modular architecture
Robert J Ingham1, Gerald Gish1 and Tony Pawson1,2Top of pageAbstractNeuronal precursor cell expressed developmentally downregulated 4 (Nedd4) is the prototypical protein in a family of E3 ubiquitin ligases that have a common domain architecture. They are comprised of a catalytic C terminal HECT domain and N terminal C2 domain and WW domains responsible for cellular localization and substrate recognition. These proteins are found throughout eukaryotes and regulate diverse biological processes through the targeted degradation of proteins that generally have a PPxY motif for WW domain recognition, and are found in the nucleus and at the plasma membrane. Whereas the yeast Saccharomyces cerevisiae uses a single protein, Rsp5p, to carry out these functions, evolution has provided higher eukaryotes with several related Nedd4 proteins that appear to have specialized roles. In this review we discuss how knowledge of individual domain function has provided insight into the physiological roles of the Nedd4 proteins and describe recent results that suggest discrete functions for individual family members.
Keywords: ubiquitination, Nedd4, E3 ubiquitin ligase, HECT, WW, C2
Top of pageIntroductionE3 protein ubiquitin ligases have the critical role of selecting specific proteins for conjugation to ubiquitin (Varshavsky, 1997). There are two main classes of such E3 ligases, proteins with a HECT (homologous to E6 AP carboxyl terminus) catalytic domain (Huibregtse et al., 1995) and proteins with a zinc binding RING finger (really interesting novel gene) (Joazeiro and Weissman, 2000) adaptor domain. Three additional E3 ligase domains, the U Box (Hatakeyama et al., 2001; Jiang et al., 2001), PHD (Boname and Stevenson, 2001; Coscoy et al., 2001; Lu et al., 2002) and HUL 1 (Van Sant et al., 2001) sequences have recently been described. Polypeptides of the Nedd4 family belong to the HECT class of E3 ligases (Harvey and Kumar, 1999; Rotin et al., 2000).
Nedd4 was originally identified in 1992, in a screen for genes developmentally downregulated in the early embryonic mouse central nervous system (Kumar et al., 1992), and resembles other regulatory proteins in containing multiple, distinct modular domains (Pawson and Nash, 2003). Subsequently, related proteins with similar structures have been characterized. All contain a catalytic HECT domain at the C terminus, and an N terminal region involved in substrate recognition, that includes a C2 domain and a series of WW domains. Although the common modular architecture of the Nedd4 family might suggest a redundant functional role for these proteins, recent work has begun to define specific cellular activities for individual members, and to suggest mechanisms that underlie this specificity. This review will provide an overview of the functional properties of the modular domains comprising the Nedd4 family, and highlight physiological processes regulated by these proteins.
Members of the Nedd4 protein familyNedd4 like proteins are found in eukaryotes from yeast to mammals and are defined by a similar domain organization (Figure 1). In Saccharomyces cerevisiae, a single member, Rsp5p, regulates a number of processes including mitochondrial inheritance (Fisk and Yaffe, 1999), internalization of cell surface receptors (reviewed in Rotin et al., 2000), and transcription (Huibregtse et al., 1997). Furthermore, the function of this protein is critical, as disruption of the rsp5 gene is lethal (Hein et al., 1995). The domain architectures of all known Nedd4 proteins are illustrated and designated by accession number and common name. The relative position of the C2 (green), WW (red), and HECT (blue) domains were obtained by blasting the indicated sequences against the Conserved Domain Database (Marchler Bauer et al., 2002, 2003). In cases where multiple protein products have been reported only the largest protein product is illustrated. Based on analysis from the Conserved Domain Database the C2 domain of murine NEDD4 1 may be truncated. The bar at the top represents 200 amino acids
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In Schizosaccharomyces pombe, genetic disruption of any one of the three family members, pub1, pub2, and pub3, results in a viable phenotype (Nefsky and Beach, 1996; Tamai and Shimoda, 2002). However, pub1 and pub3 double mutants are lethal, suggesting that Pub1p and Pub3p may have overlapping functions (Tamai and Shimoda, 2002). In contrast, a mutant deficient in both Pub1p and Pub2p is viable suggesting either that Pub2p is nonessential, or that Pub3p can compensate for essential functions of Pub2p.
Caenorhabditis elegans and Drosophila melanogaster each have three Nedd4 family members. Downregulation by RNA interference of mRNA encoding the C. elegans protein CeWWP1 causes defects in morphogenesis in the developing embryo (Huang et al., 2000a). In Drosophila, dNedd4 is involved in axon guidance by inhibiting signaling through the Robo receptor (Myat et al., 2002) while Suppressor of deltex (Su(dx)) negatively regulates signaling through the Notch receptor (Fostier et al., 1998; Cornell et al., 1999). dSmurf antagonizes the transforming growth factor (TGF ) homolog decapentaplegic (DPP) (Podos et al., 2001), which regulates dorsoventral patterning in the developing embryo.
The Nedd4 family has expanded further in mammals, and the existence of multiple spliced isoforms suggests additional complexity (Chen et al., 2001; Dunn et al., 2002; Flasza et al., 2002; Itani et al., 2003). There are only limited data regarding the functional similarities and differences of the various Nedd4 family proteins and their isoforms. However, mice homozygous for a loss of function mutation in the itch gene develop a variety of inflammatory problems, indicating that the Itch protein has nonredundant functions (Hustad et al., 1995; Perry et al., 1998).
Domain architecture of the Nedd4 proteinsAlthough structural studies have not yet been reported for a full length Nedd4 protein, the individual domains have received considerable attention (Figure 2). The catalytic HECT domain was first revealed as a 40 kDa region of the protein E6 AP, a cellular enzyme recruited by the E6 oncoprotein of the human papillomavirus (HPV) associated with cervical cancers (Huibregtse et al., 1993a, 1993b). In these cancers, downregulation of the tumor suppressor protein p53 is an ubiquitin mediated process originating from the E6 induced association of p53 with E6 AP. Biochemical studies of the E6 AP HECT domain found that this region is necessary and sufficient for ubiquitin transfer and that a cysteine residue played a critical role (Scheffner et al., 1995). The mechanism involves initial binding of an ubiquitin conjugated E2 to the HECT domain with subsequent thiol ester exchange to transfer the ubiquitin moiety from the E2 to the catalytic cysteine in the E3. Transfer of ubiquitin then occurs to either a target protein or to another ubiquitin molecule to promote a polyubiquitin chain. In both cases, the ubiquitin is transferred from the E3 catalytic cysteine to a lysine side chain amino group forming an isopeptide bond (Schwarz et al., 1998; Wang et al., 1999). (a) The two lobes that compose the HECT domain are shown in the E6 AP crystal structure (PDB 1D5F). The E2, UbcH7, binds to the N terminal lobe of the HECT domain in an orientation that would direct a conjugated ubiquitin molecule towards the catalytic cysteine within the E6AP C terminal lobe. (b) WW domains are formed by a three stranded anti parallel sheet as shown for the Nedd4 WW domain (PDB 1I5H). A ligand that contains a PPxY motif, forming a polyproline type II helix, binds primarily to one face of the WW domain sheet. (c) The loop regions of the C2 domain, found at one end of the sandwhich fold, form the binding site for calcium and phospholipids as shown in the Synaptotagmin 1 C2B domain (PDB 1K5W)
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Two HECT domain structures, from E6 AP (Lan et al., 1999) and the Nedd4 family member WWP1/AIP5 (Verdecia et al., 2003), have been determined by X ray crystallography. Significant differences exist between the two structures, providing insight into how the catalytic activity of the HECT domain is regulated. In both structures the domain is composed of two lobes linked by a flexible hinge loop (Figure 2a). As the E6 AP HECT domain was cocrystallized with the E2 UbcH7, the structure reveals the E2 binding site within the N terminal lobe. This region is only moderately conserved between different HECT domains, which likely reflects differing specificities for one of the over 30 different E2s (Jentsch, 1992). In particular, E6 AP binds the E2 UbcH7 with high affinity, while the yeast Nedd4 protein Rsp5p prefers UbcH5 (Kumar et al., 1997). All known catalytic residues are located in the C terminal lobe of the HECT domain, including the catalytic cysteine that is the transient acceptor for ubiquitin prior to transfer to the final product.
The two structures differ in the relative orientation of the N and C lobes. In the E6 AP structure, the two lobes display an L shaped architecture, with conserved residues lining a broad catalytic cleft at the junction between the lobes. Consistent with the suggestion that this cleft forms part of the HECT active site, inactivating mutations in E6 AP that cause the neurological disorder Angelman Syndrome are localized to this region (Kishino et al., 1997; Jiang et al., 1999). However, the E6 AP/UbcH7 structure also presented a problem in that the position of the E3 catalytic cysteine is 40 distant from the E2 cysteine conjugate. Clearly, large conformational changes would be required to allow efficient thiol ester exchange to occur. The WWP1/AIP5 structure supported this notion, since the N and C terminal lobes were positioned such that the two cysteines would be closer together (16 Further, molecular modeling showed that this distance could be reduced to 5 if the relative orientation of the lobes were altered by rotation about the hinge loop (Verdecia et al., 2003). The importance of the flexible hinge linking the two lobes was further demonstrated by mutation and deletion analysis, predicted to restrict the relative movement of the lobes, which resulted in inhibited autoubiquitination. The inferred importance of the hinge has led to the proposal that the HECT domain functions as a ratchet to transfer ubiquitin from the E2 to the E3 catalytic cysteine. Motion about the hinge causes separation of the two lobes allowing the C terminal lobe to ubiquitinate the substrate while the N terminal lobe is recharged with an E2 ubiquitin conjugate.
Although these structural data have provided insight into the mechanism of action of the HECT domain, they have not definitively addressed how ubiquitin is transferred to the eventual substrate. It is unclear, for example, whether a polyubiquitin chain is formed by individual transfer of single ubiquitin molecules or whether a polyubiquitin chain is assembled on the E3 ligase and then directly added to the substrate. Recent data suggesting that some HECT domains may control the site of attachment on growing ubiquitin chains further complicates this issue. Proteins designated for proteasomal degradation are modified by attachment of a chain of ubiquitin molecules linked through lysine 48 of ubiquitin (Chan and Hill, 2001). For the HECT domain containing protein KIAA0010, assembly of ubiquitin chains linked through lysine 29 or 48 is possible (You and Pickart, 2001). Furthermore, Rsp5p can promote the formation of polyubiquitin chains linked through lysine 63 (Galan and Haguenauer Tsapis, 1997; Springael et al., 1999; Soetens et al., 2001). In addition, it is not known if the HECT domain plays a direct role in selecting substrates for mono or polyubiquitination.
The C2 domain and multiple WW domains N terminal to the HECT domain regulate cellular localization and substrate selection by the Nedd4 proteins. The WW domain, a small module consisting of approximately 35 amino acids and named for the presence of two conserved tryptophan residues spaced 20 amino acids apart, appears to mediate substrate recognition (reviewed in Zarrinpar and Lim (2000); Macias et al., 2002). Each family member has at least one WW domain with most possessing three or four modules located over a large middle region of the protein to form a substrate recognition scaffold.
WW domains are found in a variety of different proteins and have been shown to bind predominately proline rich motifs, including PPxY (amino acid single letter code; where x is any amino acid) (Chen and Sudol, 1995), PPLP (Bedford et al., 1997), PR (Bedford et al., 1998, 2000) and phosphoserine/threonine (pS/pT) residues that precede a proline residue (Yaffe et al., 1997; Lu et al., 1999). The Nedd4 family WW domains primarily recognize PPxY motifs but they have also been shown to bind to pS/pT residues (Lu et al., 1999) and may interact with other ligands (Qiu et al., 2000; Courbard et al., 2002; Murillas et al., 2002).
Several WW domain structures have been solved and the ligand binding determinants for the PPxY motif characterized (Figure 2b) (Kanelis et al., 1998: Huang et al., 2000b; Verdecia et al., 2000; Kanelis et al., 2001; Pires et al., 2001). WW domains possess a consensus three stranded anti parallel sheet fold that forms a hydrophobic ligand binding groove, together with a conserved binding pocket (termed the XP groove), which is generated by the juxtaposition of two large aromatic residues. The PPxY ligand yields a polyproline type II helix, and the two prolines are packed into the XP groove. The tyrosine makes several important interactions including a hydrogen bond with a conserved histidine residue as seen in the dystrophin WW domain (Huang et al., 2000b). This might explain the requirement for the tyrosine residue seen in biochemical studies (Chen and Sudol, 1995; Chen et al., 1997; Kasanov et al., 2001; Otte et al., 2003). Other interactions between the peptide and WW domain may also be important. For instance, the structure of the third WW domain of rat Nedd4 with a peptide from the ENaC channel shows an extended PPxY motif, PPxYxxL, binds the WW domain, with the leucine making important contacts. Binding studies support this result as a peptide with a leucine to alanine substitution displayed a six fold lower affinity than the wild type peptide (Henry et al., 2003).
The C2 domain was first identified in classical Protein Kinase C isoforms as a Ca2+ dependent phospholipid binding domain (reviewed in Rizo and Sudhof, 1998). It is approximately 120 amino acids and is composed of two four stranded sheets oriented to form an eight stranded sandwich structure (Figure 2c) (Sutton et al., 1995; Grobler et al., 1996; Essen et al., 1997; Perisic et al., 1998). Loop regions between the strands at the ‘top’ of the sandwich contain a number of conserved aspartate residues that are responsible for Ca2+ binding (Sutton et al., 1995; Essen et al., 1996; Shao et al., 1996). C2 domains have been shown to interact with a variety of phospholipids and proteins (Nalefski and Falke, 1996) and are thought to function as membrane recruitment domains involved in protein localization and trafficking. Indeed, the C2 domain is found in many proteins that require association with phospholipids at membrane surfaces for function, such as RasGAP, Synaptotagmin and several phospholipases (Ponting and Parker, 1996).
Physiological processes mediated by Nedd4 proteinsUbiquitin mediated processes are involved not only in the targeting of proteins for degradation by the 26S proteasome but also in the sorting of proteins at different steps in biosynthetic and endocytic pathways (Hicke, 2001; Bonifacino and Traub, 2003). Proteins at the plasma membrane are tagged with monoubiquitin to direct internalization. Within vesicles the ubiquitinated proteins are then transported to the late endosome and further sorted, in the multivesicular body, for recycling to the plasma membrane or destruction at the lysosome. Ubiquitin mediated protein sorting also occurs at the trans Golgi network where newly synthesized proteins, such as the amino acid permeases, are directed to the cell surface or targeted for destruction in the lysosome. The Nedd4 proteins participate in these processes through ubiquitination of target proteins.
While S. cerevisiae has only a single Nedd4 member, Rsp5p, other eukaryotes have several Nedd4 proteins that appear to have both redundant and specialized functions (Figure 3). Here, we describe one function of Rsp5p in the regulation of cell surface receptors in yeast. As examples of how the Nedd4 proteins function in mammals, we discuss how several Nedd4 proteins appear to operate in the downregulation of the epithelial sodium channel (ENaC) while Smurf1 and 2 have evolved specialized functions in the control of TGF signaling. Finally, we discuss how viruses have co opted the Nedd4 proteins to regulate various aspects of the viral life cycle. In particular, that Epstein virus (EBV) recruits Nedd4 proteins for the maintenance of viral latency in B cells and retroviruses utilize these proteins to bud from the cell. Selected cellular processes regulated by the NEDD4 family of proteins from yeast to higher eukaryotes are shown. Details regarding the specific roles of the NEDD4 family proteins in each of the processes are provided in the text. Current understanding of the role played by individual family members in the regulation of these processes is illustrated, however the involvement of other family members not yet investigated cannot be discounted
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Regulation of yeast membrane proteinsRsp5p mediated regulation of cell surface receptors is one mechanism used by S. cerevisiae to adapt to environmental changes. For example, the Gap1p general amino acid permease is upregulated when it is necessary to use amino acids as a nitrogen source (reviewed in Magasanik and Kaiser, 2002). However, when yeast are grown on ammonia, Gap1p is degraded in an ubiquitin mediated manner (Springael and Andr 1998). Similarly, the factor receptor, Ste2p, the uracil permease, Fur4p, and several other cell surface receptors are regulated by ubiquitination in response to different stimuli (reviewed in Rotin et al., 2000).
The ubiquitination, internalization, and degradation of Ste2p, Gap1p, and Fur4p are all dependent on Rsp5p (Hein et al., 1995; Galan et al., 1996; Dunn and Hicke, 2001a). In the case of Ste2p and Fur4p, receptor degradation occurs not through the proteasome but via the lysosome like vacuole (Galan et al., 1996; Hicke and Riezman, 1996). In fact, in frame fusion of a single ubiquitin molecule to the C terminus of Ste2p is sufficient for internalization and degradation of the receptor (Terrell et al., 1998; Shih et al., 2000; Dunn and Hicke, 2001b), and monoubiquitination of Fur4p is also sufficient for internalization (Springael et al., 1999a). Fur4p and Gap1p are also polyubiquitinated (Galan and Haguenauer Tsapis, 1997; Springael et al., 1999a; Soetens et al., 2001). However, the polyubiquitin chains are not linked through lysine 48, which normally targets proteins to the proteasome, but are linked through lysine 63. This is consistent with polyubiquitinated Fur4p and Gap1p not being substrates of the proteasome. Furthermore, Rsp5p has functions in addition to ubiquitination of Ste2p, as the Ste2p/ubiquitin chimera still requires Rsp5p for internalization and degradation (Dunn and Hicke, 2001b).
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The company also increased its market share in both the heavy and medium commercial vehicle segment during the year, according to the 2007 08 annual report of Tata Motors.The annual report says that Tata Motors subsidiaries have significantly improved their financial performance during 2007 08. Tata Motors acquired Daewoo Commercial Vehicle Company in March 2004 for Rs 495 crore.According to the annual report, Tata Daewoo Commercial Vehicle Co (TDCV) increased sales by 38 per cent to 11,899 units in 2007 08, against 8,588 units sold in the previous year. Consequently, the company increased its market share to 32.3 per cent from 24.3 per cent in the heavy commercial vehicle segment and to 34.8 per cent from 28.2 per cent in the medium commercial vehicle segment.TDCV exported 3,000 units of HCVs (2,715 in the previous year) and continued to be the largest exporter from Korea in this segment.The company sold 7,698 machines during the year against 5,360 machines in 2006 07. is 60 per cent owned by Tata Motors and the balance by Hitachi Construction Machinery Co Ltd, Japan.The annual report shows that Tata Motors has 26 subsidiaries, with some of them having just begun operations. Eleven of the subsidiaries have shown a loss for the year and five of them have declared a dividend for the year.Tata Motors bought a 21 per cent stake for Rs 70 crore in March 2005 and has the option to buy the remaining 79 per cent at a price not exceeding million (about Rs 14 crore).Hispano has two manufacturing units, one in Spain that caters to the European market and the other in Casablanca, which caters to the Moroccan and other North African markets.
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(CNN) Cientficos en el rtico descubrieron el florecimiento de fitoplancton ms grande que se haya encontrado bajo una capa de hielo. Este hallazgo, de acuerdo con los expertos, equivale a descubrir el Amazonas en medio del desierto Mojave.
Los investigadores se sorprendieron al descubrir la colosal cantidad de 100 kilmetros de fitoplancton creciendo bajo el hielo rtico, en julio del ao pasado, en la regin norte de Alaska.
Anteriormente se daba por hecho que que el hielo bloqueaba los rayos del sol necesarios para el crecimiento de las plantas marinas. Pero se encontr cuatro veces ms fitoplancton debajo del hielo que en las aguas despejadas de la zona.
Los cientficos creen ahora que las albercas de hielo derretido funcionan como domo y lentes de aumento, enfocando los rayos del sol al agua de mar y crean las condiciones perfectas para el florecimiento adecuado del fitoplancton, lo que hace que .
El fitoplancton del ocano fue descubierto en la dcada de 1970 y ahora sabemos que es tan importante para la produccin del oxgeno que se encuentra en nuestra atmsfera como las plantas en la tierra.
Las consecuencias ecolgicas del brote polar an no han podido evaluarse en su totalidad, pero dada la posicin del fitoplancton en la base de la cadena alimenticia, los cientficos esperan que tenga implicaciones para los animales del ocano que se alimentan en el rea.
Fue un descubrimiento azaroso para los cientficos que, como parte del programa Impactos del Clima en los Ecosistemas y la Qumica del Medio Ambiente en el Pacfico rtico (ICESCAPE, por sus siglas en ingls) de la Administracin Nacional de Aeronutica y del Espacio de Estados Unidos (NASA), estudiaban el impacto del cambio climtico en el mar Chukchi, en donde la temporada de deshielo provoca cambios profundos en el rea.
Abrindose paso por el hielo de un metro de grosor a bordo del Healy, el rompehielos ms grande de la Guardia Costera de los Estados Unidos en julio del ao pasado, los cientficos observaron con sorpresa las cantidades de clorofila fluorescente, indicando la presencia de la fotosntesis de la vida de las plantas.
"Si alguien me hubiera preguntado antes de la expedicin si veramos brotes debajo del agua, les hubiera dicho que era imposible", dijo Kevin Arrigo, jefe de la misin ICESCAPE de la Universidad de Stanford, en una conferencia de prensa que anunciaba la publicacin de los descubrimientos en la revista especializada Science de este mes. "Este descubrimiento fue toda una sorpresa".
Donald Perovich, geofsico americano que estudi las propiedades pticas del hielo, describi al rea bajo el hielo como si fuera un negativo fotogrfico.
"Debajo de las reas sin hielo que reflejan muchos rayos solares, era obscuro. Debajo de los estanques derretidos, era muy brillante", explic.
Los cientficos descubrieron que las albercas derretidas permitan el paso de cuatro veces ms luz que la del hielo cubierto de nieve. Protegido de los rayos ultravioleta, el fitoplancton crece dos veces ms rpido debajo del hielo que en el mar abierto.
Para la investigacin usaron un sistema de microscopio automatizado llamado Imaging FlowCytobot. Sam Laney, bilogo de la Institucin Oceanogrfica de Woods Hole, tom , algunas de las que tambin encontr en los canales de agua de mar dentro del hielo.
El tipo de plancton encontrado cerca de las costas puede florecer rpidamente cuando hay cambios en la disponibilidad de la cantidad de luz y nutrientes. Algunos brotes son txicos para los humanos y la vida marina.
Si el hielo del rtico sigue adelgazndose, los brotes pueden expandirse an ms y aparecer ms rpido, lo que puede ser un problema para las aves y ballenas migratorias, dijo Arrigo.
"Cuando los brotes estn en su mximo esplendor pueden hacer ms y ms difcil la medicin de los ciclos de vida de las especies migratorias para estar en el rtico", dijo. "Si su suplemento alimenticio llega antes, pueden perderse el bote".
"En este punto no sabemos si los ricos brotes de fitoplancton han estado sucediendo en el rtico por mucho tiempo, o si simplemente no los habamos observado", agreg.
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I don’t remember what we did to youghurt pots but it involved heating them. Meybey I’ll buy a yoghurt and heat teh pot to find out. i was never very creative with crisps. But I used to (and in fact when she’s around still do) get at my older sister for putting decent crisp flavours into sandwiches. See, in our household, Cheese and Onion was unpopular, beef was mildly popular. Ready salted and chicken were normal and everything else was popular. but she’d still put salt’n’vinegar on a sandwich leaving a mass of bags of cheese and onion crisps left over (Which I think work better in sandwiches anyway)
Despite not wanting to buy Pringles (and full fat anything always tastes better, but at my age the fat shows immediately!) I have to say that I am endlessly fascinated by them. The shape for one, the fact that the tube really does keep them crisp for ages, etc. etc. I’m going to go home later and lick a whole packet on each side to test your theory. But probably they only salt one side because it rubs off onto the non salted side of the other crisps in the packet. I’m going to lick them anyway.
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Former Ukrainian Prime Minister Pavlo Lazarenko may find an inquiry from Marin County tax collector Roy Given waiting when he is released from the federal prison at Terminal Island on Nov. 1.
Lazarenko, who has been cooling his heels behind bars for the past six years following his conviction for money laundering, transporting stolen goods and fraud, owes Marin $2.1 million in back taxes and late payment fines levied against the palatial, 11 acre Novato mansion at 100 Obertz Lane he once called home. deadline for paying 2011 12 property taxes. Tardy taxpayers face a 10 percent penalty.
Given, head of the Department of Finance at the Civic Center, said that Dugsbery Inc. of Sausalito, the entity through which Lazarenko bought the mansion, is Marin’s biggest tax scofflaw. The bill includes $894,407 in back taxes and another $997,824 in late payment penalties, as well as $129,000 on two adjacent parcels. The properties are among 1,487 Marin County parcels that owe $20,703,732 in back taxes, penalties and interest.
"I’d like these people to call my office and try to work out a payment plan," Given said, adding that it’s been hard to contact Lazarenko, "since he’s been in prison."
The next step for the Novato mansion will be "final formal notifications, including to the state Franchise Tax Board and the IRS, and then we’ll be forced to put the property up for a tax sale," probably in late August, he said. Disposition of the property will be delayed if the federal or state governments makes a claim.
Officials said that the 59 year old Lazarenko, once ranked as the eighth most corrupt official in the world by an international watchdog group, pocketed millions when he controlled lucrative oil and gas contracts as head of the Ukrainian government in fiscal 1996 97. Ousted from office, he fled amid controversy in 1999 to seek asylum in the United States and wound up in Marin. Federal prosecutors accused him of stealing $114 million while in public office and trying to hide $21 million in American banks, including $9.3 million deposited in the Sausalito branch of Westamerica Bank, and he went on trial in San Francisco. He was convicted and sentenced to nine years in prison and fined $10 million.
Prosecutors said he paid cash siphoned from the Ukraine to buy the Novato mansion overlooking the Marin Country Club for $6.75 million. The 19,495 square foot, nine bedroom, nine bath residence has two helicopter landing pads, five dog kennels, a ballroom, granite floors inlaid with brass, and gold plated door knobs.
The mansion was built by George Michael Shipsey, a former Marin developer convicted in 1997 of embezzling $700,000 in union pension funds. Movie star Eddie Murphy created a local stir when he rented the home for a time.
Given called Lazarenko’s lofty, tardy tax bill an aberration, and noted that most taxpayers will pay up before Tuesday’s deadline. County staffers on Monday will sort thousands of bills mailed in over the weekend.
Given’s staff already is knee deep in tax bills as sacks of mail have poured in and employees process 8,000 payments a day. Hundreds more appear to pay up in person, like those in a line last Thursday afternoon that snaked through the tax office lobby.
"It’s just been fine. People are happy," said veteran tax cashier Katherine Haley. "Some people are concerned about all the special assessments" imposed by various taxing districts, she added.
Joani Metolius of Novato was among the taxpayers waiting to pay the tax collector.
"It costs me only $14 a day for the privilege of living in this wonderful, most beautiful county," she said of her tax bill.
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After the prolonged media coverage of the build up to, and London’s victory in, the 2012 Olympics race, it seems hard to believe that the last time the summer Olympics were held in London, the city was up against no competition whatsoever. After the turmoil caused by the Second World War and two Olympic cancellations, the UK simply volunteered its capital as host city for 1948 and was willingly accepted by the International Olympic Committee. Wembley Stadium was pressed into temporary service as the main venue, and the Games were broadcast on television for the first time, even though very few had TV sets.
Sporting NationsIt was not to be an Olympics of daring innovation. The world was still recovering from the shock of large scale war and many countries were still in depression. The primary aim of the London Olympics was to draw countries together, not to emanate glitz and glamour. Great Britain had not conceded a single goal in their progress to the final, and yet were humbled 4 0. Hockey has remained a national sport in India ever since.
Other nations celebrating in 1948 included Sri Lanka (Ceylon, as it was at the time) and Korea, both of whom took home their first ever Olympic medals; their heroes being Duncan White (400m Hurdles) and Kim Sung Jip (Middleweight Weightlifting) respectively.
Sporting LegendsFor many people, the 1948 Olympics belonged to Dutch athlete Fanny Blankers Koen. ‘The Flying Housewife’ was already a very successful athlete in her own right. She had competed in the 1936 Olympics at the age of 18, and at the time of the Olympics held world records for 100m, 200m, 80m hurdles, long jump and high jump. She had given birth to a daughter (also called Fanny) just three months before entering the 1946 European Championships, winning two gold medals there. Sensibly declining to enter the jumping events in London, she took four gold medals home to Amsterdam: 100m, 200m1, hurdles and sprint relay. It is unlikely that this achievement of four golds in a single Games will ever be matched in the world of female athletics.
Another track and field athlete was taking his first steps to becoming a legend, but almost had his glory upset by some incompetent officiating. Emil Ztopek had served with distinction for Czechoslovakia during the war and was still serving at the rank of Lieutenant when he took the trip to London. He set off in the 10,000m final at a rate of knots and became the first man to run that distance under 30 minutes at the Olympics, winning by nearly a lap of the track. He was so far ahead that the steward neglected to ring the bell signifying the final lap. The said steward claimed to be watching the pole vault, and was presumably given a stiff dressing down later. Despite the confusion in the stadium, which later mixed up most of the lower placings in the race, Ztopek knew he had won. He came second in the 5,000m at London but completed an amazing long distance treble four years later in Helsinki, adding the marathon title on the final day to his 5,000m and 10,000m successes.
An established legend in the world of fencing was also present in London. Aladr Gerevich had won medals for Hungary before the War in both 1932 and 1936, and comfortably won gold in London with an undefeated record. Gerevich went on to win seven gold medals up to 1960, when he competed in his last Olympics in Rome at the age of 50.
Another serial winner just starting out was Denmark’s Paul Elvstrm. His gold in yachting’s ‘Finn’ class at the age of 18 was to be the first of four consecutive Olympic titles.
HeroesIt was a very muted games for the home team, their ranks depleted by stringent post war conditions. The British team netted just three gold medals, although they did claim 14 silvers. All the British successes were on the water: in the rowing at Henley, Burnall and Bushell were victorious in the double sculls; Wilson and Laurie (who had served together in Sudan for the previous ten years) won the coxless pairs. On the sea, Stewart Morris and David Bond were the winners in the London to Torbay ‘swallow’ class yachting the only time this class has appeared at the Games.
The hero of Wembley stadium was unanimously the Belgian marathon runner, Etienne Gailly. Gailly had never run a marathon before, but traded the lead with more established names throughout the first 26 miles. He entered the stadium first, shortly ahead of Argentina’s Delfo Cabrera and Britain’s Thomas Richards. Gailly had barely a lap of the track to complete, but the crowd could see his legs wobbling and his path wavering to and fro. Groans rang out around the stadium as he dried up to a walk and was overtaken by Cabrera and Richards. In a shocking reminiscence of Pietro Dorado collapsing within view of the tape 40 years earlier (the last time the Games had been held in London), Gailly fell to his knees on the home straight. But, to a standing ovation, he straightened up and staggered over the finishing line for a bronze.
Inevitably, the War was to produce its own heroes. Many of those competing in London were veterans, and a few were even carrying injuries sustained in combat. None was more remarkable than Hungarian pistol shooter Kroly Takcs. Originally right handed, his shooting hand was shattered and left unusable by a grenade while he was in service. Takcs nevertheless brought himself quickly up to Olympic standard, shooting with his left hand, and he achieved a much acclaimed gold in London. This feat is all the more remarkable when one considers that it often takes over 20 years for a shooter to reach Olympic standard with their leading hand.
The Olympic boxing had seen bad temper and controversy, not least from a belligerent and self important American team, but was home to another remarkable victory through injury. Jlius Torma shattered his knuckles not like Takcs in combat, but on the jaw of an unlucky opponent in the second round. Nevertheless, he spared his left hand through his last four matches and won the Welterweight title literally single handedly.
The Old and the Young; The Tall and the Short; The Rich and the Poor31 years separated Bob Mathias and Terence ‘Tebbs’ Lloyd Johnson, a gap larger than the age of many other participants. American schoolboy Mathias had only taken up the decathlon three months before and possessed the naivety you might expect of a 17 year old. He nearly earned himself disqualifications in the shot and high jump, before going on to complete the second day in semi darkness. His discus throw was longer than anyone expected and the officials lost the marker for his longest throw. Car headlamps had to be used to highlight the foul line for his javelin throw, since conditions were so bad. But Mathias bettered the weather, darkness and red tape to become the youngest ever winner of a track and field gold medal. It is even more remarkable that he did so in one of the most physically demanding events. When asked how he would celebrate, he self deprecatingly shrugged and replied ‘I’ll start shaving, I guess’. He was back to successfully defend his title in 1952.
By contrast, Lloyd Johnson was a 48 year old veteran. His bronze medal in the punishing 50,000m walk made him by far the oldest medallist of all time at track and field. He had also competed in the 1936 Olympics, taking over the British mantle in this long and exhausting discipline from Thomas Green.
Very much fulfilling the ‘short’ category was Bantamweight weightlifter Joe di Pietro of the USA. Boasting an abnormally small frame of well under five feet, with arms that were barely long enough to lift the weights over his head, di Pietro set lasting Olympic and World Records for his weight category, being contested for the very first time.
No Olympics would be without its moments of light hearted heroics. In London, these were mostly provided on the basketball court. The Iraqi team provoked much amusement with its rank incompetence (they lost two matches by over 100 points), but the highlight for many was watching a diminutive Chinese point guard dribbling the ball right through the legs of the mammoth US centre, Bob Kurland. China and Iraq went on to finish 18th and 19th respectively.
Less amusing were the ridiculously antiquated equestrian rules. The dressage events were reduced to farce when it was pointed out that one of the Swedish riders, Gehnll Persson, was riding in a sergeant’s cap. As only commissioned military officers2 were permitted to compete, the Swedish team was disqualified and robbed of the gold medals which should have been rightfully theirs. The incident clearly made a nonsense of the socially elitist world of equestrianism, and the laws were changed soon afterwards.
Equestrianism, though, was just one of many sports to be dragged into the modern era by the London Olympics. Although the Games were hastily organised and often substandardly run, they played an essential part in rekindling the spirit of competition and the likes of Blankers Koen, of Zatopek and of Mathias played a vital part in promoting and inspiring sporting excellence into the second half of the 20th Century.
1Blankers Koen won the 200m on its first Olympic appearance, by a margin of over seven metres and by nearly a second, a distance unmatched ever since.2ie, those of ranks of lieutenant and above.
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Consider the price. If you buy directly from Ralph Lauren, a handbag costs anywhere from $1,000 to $20,000, with most bags falling in the $1,500 to $3,000 range. Bags from past seasons have a high retail value, and even older bags sell for hundreds of dollars. A handbag that costs much less than the going rate is almost certainly a fake.
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Notice the quality of the material. Ralph Lauren handbags are made from the highest quality animal skin. A knock off will be made of low quality or imitation material, and the difference is stark. Real leather, for example, feels soft and supple, while mock leather, which may look similar, feels hard and stiff to the touch.
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File Photo of Matthias Mueller, CEO of German Car maker Porsche. (AFP)
Frankfurt: Matthias Mueller, head of luxury sportscar maker Porsche, looks set to take the steering wheel at scandal hit Volkswagen, replacing Martin Winterkorn who stepped down two days ago.
VW’s supervisory board was scheduled to approve the appointment of the 62 year old manager, at a meeting in the carmaker’s headquarters in Wolfsburg, northern Germany, on Friday morning.
Mueller, born in the former East Germany, had already been tipped to take over during a bitter leadership struggle earlier this year between Winterkorn and his one time mentor and former supervisory board chief Ferdinand Piech.
It was Winterkorn who eventually won that battle, only to fall this week over the pollution cheating scandal, the biggest ever to hit VW.
Both Mueller’s and Winterkorn’s careers are closely interlinked.
They already worked together at VW’s top line brand, Audi, in Ingolstadt in Bavaria, where Mueller began his career and Winterkorn was appointed chief in 2002.
And at more or less the same time that Winterkorn was appointed CEO at the entire VW group in 2007, Mueller went to Wolfsburg, too, where he took charge of the projects department and was subsequently made a general representative of the group.
Football fan
Born on June 9, 1953, in Limbach Oberfrohna in former East Germany, Mueller fled to the West, to the neighbouring regional state of Bavaria, with his parents.
He told the daily Die Welt that he originally wanted to become a professional football player.
And he is still a keen soccer fan and supporter of FC Bayern and Stuttgarter Kickers, according to the mass circulation daily Bild.
But in the end, Mueller trained as a tool maker at Audi and went on to study information technology in Munich.
According to Die Welt, Mueller is a man "who loves cars and who loves people who love cars."
His first car was a VW Beetle and he now owns an Audi TT and Porsche 911, according to Bild. And he occasionally likes to go for a jaunt in the legendary Porsche 550 Spyder sports car that he borrows from Porsche’s own museum.
Die Welt dubbed him "the imperturbable" and said he was someone who knows how to use his elbows.
"But I don’t see it as playing foul, rather as a sign of perseverance and mettle," the newspaper quoted him as saying.
Uwe Hueck, head of Porsche’s works committee, said Mueller "has the whiff of Porsche about him. His engine is seated lower and he has wide tyres."
Mueller who tends to lapse into a strong Bavarian dialect when not on duty was appointed CEO at Porsche in 2010, not long after VW had emerged victorious in its tortuous takeover battle with Porsche.
As far back as 2005, Porsche hatched an audacious plan to take control of VW which was 15 times larger than Porsche.
But the plan ran out of steam a result of the financial crisis and failed to win enough support from VW’s shareholders. This led to VW turning the tables on Porsche and taking over the sports car maker.
"Porsche has come along very successfully and is now in better shape than ever before," he beamed.
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