bluuebunny/crossref_metadata_2025 huggingface dataset:
Excerpts from the EU‐integration Story of Hungarian Agriculture: Heading Where?
Authors: Popp Jozsef , Potori Norbert
Published: July 2006

Cereal production in Hungary doubled in 2004/2005 over the previous year and was 4 per cent lower in 2005/2006. There were 3.9 million tones of cereals taken into intervention in the 2004/2005 season, while until January 8, 2006, an additional 3.7 million tonnes of new crop were offered. High transport cost is a serious drawback for wheat and maize, produced under otherwise good natural conditions in the CEE region, in competing within the EU or in third country markets. The combined effects of an intervention price above ε90 a tonne, the implementation of the SPS and the decoupling of the national ‘top‐up’ for arable crops together with the introduction of compulsory set‐aside are unlikely to reduce cereal production in Hungary. Under normal conditions, 14.5–15 million tonnes of cereal stocks could be accumulated by 2010. In the pre‐accession years livestock producers in Hungary enjoyed some direct subsidies but they had almost no access to investment and capital aids. This and the late approval of rural development programmes contributed largely to the decline in production. Despite huge excess stocks of cereals, the prospects for these major feed grain consuming sectors to expand look rather slim in the mid‐term, due mainly to structural problems and the lack of capital for modernisation. Taken together these factors are likely to keep cereal market prices in Hungary under pressure in the next few years, despite the implementation of the SPS.
More or Less Ambition in the Doha Round? Modeling the Development Impact of Recent Proposals
Authors: Bouet Anoine , Mevel Simon , Orden David
Published: July 2006

We analyse the impact on developing countries, whose economies depend heavily on agriculture, of a WTO Doha Development Round agreement based on greater or lesser levels of ambition. We present the results of an ambitious versus an unambitious Doha Round outcome, using the MIRAGE model of the global economy, with a special focus on developing countries. Our simulations are based on negotiating proposals from the run‐up to the Hong Kong ministerial meeting but not agreed upon in December 2005. We compare those outcomes with the estimated effects of full global trade liberalization. The results for the two Doha scenarios demonstrate the high stakes of this negotiation given the positions of EU, US and the G‐20 coalition. A successful round could deliver real gains both globally and for developing countries, but the magnitude of those gains depends on the shape of the agreement. A reform outcome based on the most ambitious components of the negotiating proposals of the US and EU delivers noticeably greater benefits than an unambitious outcome. Developing countries are exposed to very contrasting fortunes. The details matter in the differing proposals, such as the tariff and domestic support reduction formulae, tariff caps, and number of sensitive and special products. Negotiating commitment and diligence are needed in 2006 to avoid a hollow Doha outcome given the technical character of these details.
Strengths and Weaknesses of Crosscompliance in the CAP
Authors: Bennett Harriet , Osterburg Bernhard , Nitsch Heike , Kristensen Lone , Primdahl Jørgen , Verschuur Gerwin
Published: July 2006

Cross‐compliance has increasingly been used to integrate environmental considerations into the CAP. From 2005 it became compulsory for all Member States to ensure that recipients of Single Farm Payments adhered to Statutory Management Requirements (SMRs), stemming from 19 EU regulations and directives, and kept their whole agricultural holding in ‘Good Agricultural and Environmental Condition’ (GAEC), to be defined by Member States or regional authorities. The potential for cross‐compliance to enhance implementation of EU environmental legislation and reach a large area of farmland seems good, although there are some questions remaining over whether it will reach the agricultural land at most risk of environmental damage or with the highest nature value. In addition, farmers could react in several ways to exempt themselves or some area of their holding from cross‐compliance conditions. Member States or regional authorities have taken a variety of approaches to setting cross‐compliance standards, some of which seem minimal and vague. There is scope for the SMRs and GAEC to cover more environmental issues. Better guidance at EU level and increased communication could enhance implementation of cross‐compliance. Self‐audits, co‐operation with private assurance schemes or other methods of monitoring should be explored to maximise the efficiency and effectiveness of administrative efforts.
Sensory Properties of Whey and Soy Proteins
Authors: Russell T.A. , Drake M.A. , Gerard P.D.
Published: July 2006

ABSTRACT: Whey and soy proteins are valuable dried ingredients with applications in numerous foods. Characterization and comparison of the flavor properties of these value‐added ingredients are needed to interpret analytical flavor chemistry results and to identify specific ingredient applications and marketing strategies. The goals of this study were to develop a sensory lexicon for whey and soy proteins, and to subsequently identify and compare the descriptive sensory properties of whey and soy proteins. Consumers also filled out a survey to probe their opinions and attitudes to dairy and soy products. Twenty‐four descriptive sensory attributes were identified to evaluate appearance, flavor, and texture/mouthfeel of rehydrated proteins. Twenty‐two samples (14 whey proteins and 8 soy proteins) were selected for descriptive sensory analysis. Proteins were rehydrated (10% solids, [w/v]) and evaluated in triplicate by a highly trained sensory panel (n= 10) trained to use the developed language. Both whey and soy proteins were differentiated using the identified language (P< 0.05). Each protein type displayed sensory variability, but different sensory attributes distinguished whey proteins from soy proteins. Consumers (n= 147) perceived distinct health benefits associated with dairy and soy products, respectively. These results will enhance ongoing research and product development with these nutritional and functional ingredients.
Trans Fatty Acid Content of Selected Foods in an African‐American Community
Authors: Huang Z. , Wang B. , Pace R.D. , Oh J.‐H.
Published: July 2006

ABSTRACT:  Trans fatty acid content was examined in several grocery foods and fast foods in an African‐American community. Food samples were selected based on the frequency of use among this population group in the local community. Samples were collected 3 times with an interval of 1 wk. Total fat content was analyzed by Soxhlet method. Fatty acids profile, including trans fatty acids, was analyzed by GC–MS. In grocery foods, no trans fatty acids were detected in fish sticks, salad dressing, mayonnaise, muffin, and potato chips. Margarine contained the highest trans fatty acid at a level of 19.13%. The trans fatty acid level in crackers, cookies, butter, chicken patties, and biscuits mix ranged from 0.51% to 1.77%. In fast foods, no trans fat was detected in dressing. All the fried food and bakery food sampled in this study contain trans fat. The level varied from 2.07% to 10.30%. The principal trans fatty acid was trans 18:1. Other trans fatty acids found were trans 18:2, trans 19:1, and trans 16:1. In a total of 23 food samples, 16 of them were found to contain trans fatty acid. The results demonstrated that trans fat is commonly found in foods of the African‐American community. The trans fatty acids content in tested samples varied from 0% to 19.13%.
Quality and Sensory Properties of Fresh Egg Noodles Formulated with Either Total or Partial Replacement of Egg Substitutes
Authors: Khouryieh Hanna , Herald Thomas , Aramouni Fadi
Published: July 2006

ABSTRACT:  The quality and sensory properties of fresh egg noodles formulated with total or partial replacement of egg substitute were investigated. Cooking quality parameters, texture, and color were measured at d 0, 15, and 30. Whole‐egg noodles (control) had less cooking loss, firmer texture, and larger L* and b* values among days compared with noodles prepared with 100% soy flour or Pasta Power. Noodles prepared with Bipro exhibited the least cooking loss and water uptake, firmer texture, and larger L* and b* values among egg substitutes at 50% replacement. Firmness was greater and L* and b* values were larger for noodles from soy flour and Pasta Power egg substitutes when they replaced 50% of egg, rather than 100%. Sensory analysis revealed the roughness and flavor of cooked noodles, which were not significantly affected by the type of egg substitute. Noodles containing Pasta Power exhibited greater stickiness, whereas those containing soy flour were less firm. Including whole eggs in the formulations reduced stickiness. None of the egg substitutes studied could totally replace whole egg in the egg noodles without resulting in some loss of quality. But partial replacement of eggs resulted in noodles with similar physical and sensory properties.
Influence of activation frequency on cellular signalling pathways during fatiguing contractions in rat skeletal muscle
Authors: Russ David W. , Lovering R. M.
Published: July 2006

Activation frequency as a regulator of physiological responses in skeletal muscle, independent of contractile force, has received little attention. Here, the length–tension and force–frequency relationships were employed to keep active contractile force equal, despite a twofold difference in stimulation frequency (15 versus 30 Hz). Rat tibialis anterior muscles were tested in situ using 15 Hz stimulation at optimal length (15 Hz) and 30 Hz stimulation at shortened and lengthened positions (30 Hzsub and 30 Hzsupra). Muscles were subjected to 1, 15, 30 and 80 Hz stimulation trains before and after 2 min of fatiguing stimulation. The principal findings were that the two 30 Hz protocols produced greater 38 kDa MAPK (p38) phosphorylation than the 15 Hz protocol (1.4‐ to 1.5‐fold versus 1.1‐fold), as well as greater fatigue (65–78 versus 43% decline in contraction force). In contrast, c‐jun amino terminal kinase (JNK) phosphorylation appeared most responsive to total (active plus passive) tension such that the changes followed the pattern: 30 Hzsupra > 15 Hz > 30 Hzsub, while 44 and 42 kDa extracellular regulated kinase (ERK1/2) phosphorylation was not significantly increased in response to any of the protocols studied. Neither glycogen depletion nor myofibre damage accounted for any of the findings, but a decline in muscle excitation (m‐wave) may have contributed to the greater fatigue seen at higher frequencies. These data suggest that neuromuscular activation frequency can influence certain signalling pathways in skeletal muscle, independent of force production.
Detecting acute changes in oxygen: will the real sensor please stand up?
Authors: Kemp Paul J.
Published: July 2006

The majority of physiological processes proceed most favourably when O2 is in plentiful supply. However, there are a number of physiological and pathological circumstances in which this supply is reduced either acutely or chronically. A crucial homeostatic response to such arterial hypoxaemia is carotid body excitation and a resultant increase in ventilation. Central to this response in carotid body, and many other chemosensory tissues, is the rapid inhibition of ion channels by hypoxia. Since the first direct demonstration of hypoxia‐evoked depression in K+ channel activity, the numbers of mechanisms which have been proposed to serve as the primary O2 sensor have been almost as numerous as the experimental strategies with which to probe their nature. Three of the current favourite candidate mechanisms are mitochondria, AMP‐activated kinase and haemoxygenase‐2; a fourth proposal has been NADPH oxidase, but recent evidence suggests that this enzyme plays a secondary role in the O2‐sensing process. All of these proposals have attractive points, but none can fully reconcile all of the data which have accumulated over the last two decades or so, suggesting that there may, in fact, not be a unique sensing system even within a single cell type. This latter point is key, because it implies that the ability of a cell to respond appropriately to decreased O2 availability is biologically so important that several mechanisms have evolved to ensure that cellular function is never compromised during moderate to severe hypoxic insult.
Can homeostatic circuits learn and remember?
Authors: Gordon Grant R. J. , Bains Jaideep S.
Published: July 2006

Alterations in synaptic strength are thought to represent the cellular basis of learning and memory. While such processes appear to be fundamental to all synapses, until recently there has been a relative dearth of information regarding synaptic ‘memory’ processes in autonomic circuits. Here we examine recent advances in our understanding of plasticity at glutamatergic synapses onto magnocellular neurosecretory cells in the hypothalamus, paying particular attention to the contributions of noradrenaline in coding long‐lasting pre‐ and postsynaptic changes in efficacy. We also highlight recent work demonstrating that glial cells play a crucial role in the induction of long‐term potentiation. Based on the work reviewed here, we have a clearer picture of the synaptic and cellular mechanisms that allow autonomic pathways to learn and remember.
Early chronic ethanol exposure in rats disturbs respiratory network activity and increases sensitivity to ethanol
Authors: Dubois C. , Naassila M. , Daoust M. , Pierrefiche O.
Published: July 2006

Chronic ethanol exposure during the fetal period alters spontaneous neuronal discharge, excitatory and inhibitory amino acid neurotransmission and neuronal sensitivity to ethanol in the adult brain. However, nothing is known about the effects of such exposure on the central respiratory rhythmic network, which is highly dependent on ethanol‐sensitive amino acid neurotransmission. In 3‐ to 4‐week‐old rats, we investigated (1) the effects of chronic ethanol exposure (10% v/v as only source of fluid) during gestation and lactation on phrenic (Phr) and hypoglossal (XII) nerve activity using anin situpreparation and on spontaneous breathing at rest in unanaesthetized animals using plethysmography; (2) the sensitivity of the respiratory system to ethanol re‐exposurein situ; and (3) the phrenic nerve response to muscimol, a GABAAreceptor agonist, applied systemically in anin situpreparation. In control rats, ethanol (10–80 mm) induced a concentration‐dependent decrease in the amplitude of both XII and Phr motor outflows. At 80 mmethanol, the amplitude of the activity of the two nerves displayed a difference in sensitivity to ethanol and respiratory frequency increased as a result of shortening of postinspiratory duration period. After chronic ethanol exposure, respiratory frequency was significantly reduced by 43%in situand by 23% in unanaesthetized animals, as a result of a selective increase in expiratory duration. During Phr burst, the ramp was steeper, revealing modification of inspiratory patterning. Interestingly that re‐exposure to ethanolin situelicited a dramatic inhibitory effect. At 80 mm, ethanol abolished rhythmic XII nerve outflow in all cases and Phr nerve outflow in only 50% of cases. Furthermore, administration of 50 µmmuscimol abolished Phr nerve activity in all control rats, but only in 50% of ethanol‐exposed animals. Our results demonstrate that chronic ethanol exposure at an early stage of brain development depresses breathing in juvenile rats, and sensitizes the respiratory network to re‐exposure to ethanol, which does not seem to involve GABAergic neurotransmission.
Molecular and electrophysiological characterization of transient receptor potential ion channels in the primary murine megakaryocyte
Authors: Carter Richard N. , Tolhurst Gwen , Walmsley Gemma , Vizuete‐Forster Matthieu , Miller Nigel , Mahaut‐Smith Martyn P.
Published: July 2006

The molecular identity of platelet Ca2+ entry pathways is controversial. Furthermore, the extent to which Ca2+‐permeable ion channels are functional in these tiny, anucleate cells is difficult to assess by direct electrophysiological measurements. Recent work has highlighted how the primary megakaryocyte represents a bona fide surrogate for studies of platelet signalling, including patch clamp recordings of ionic conductances. We have now screened for all known members of the transient receptor potential (TRP) family of non‐selective cation channels in murine megakaryocytes following individual selection of these rare marrow cells using glass micropipettes. RT‐PCR detected messages for TRPC6 and TRPC1, which have been reported in platelets and megakaryocytic cell lines, and TRPM1, TRPM2 and TRPM7, which to date have not been demonstrated in cells of megakaryocytic/platelet lineage. Electrophysiological recordings demonstrated the presence of functional TRPM7, a constitutively active cation channel sensitive to intracellular Mg2+, and TRPM2, an ADP‐ribose‐dependent cation channel activated by oxidative stress. In addition, the electrophysiological and pharmacological properties of the non‐selective cation channels stimulated by the physiological agonist ADP are consistent with a major role for TRPC6 in this G‐protein‐coupled receptor‐dependent Ca2+ influx pathway. This study defines for the first time the principal TRP channels within the primary megakaryocyte, which represent candidates for Ca2+ influx pathways activated by a diverse range of stimuli in the platelet and megakaryocyte.
Comparative Antibody-Mediated Phagocytosis ofStaphylococcus epidermidisCells Grown in a Biofilm or in the Planktonic State
Authors: Cerca Nuno , Jefferson Kimberly K. , Oliveira Rosario , Pier Gerald B. , Azeredo Joana
Published: July 2006

Staphylococcus epidermidisis an important cause of nosocomial infections. Virulence is attributable to elaboration of biofilms on medical surfaces that protect the organisms from immune system clearance. Even though leukocytes can penetrate biofilms, they fail to phagocytose and kill bacteria. The properties that make biofilm bacteria resistant to the immune system are not well characterized. In order to better understand the mechanisms of resistance of bacteria in biofilms to the immune system, we evaluated antibody penetration throughout the biofilm and antibody-mediated phagocytic killing of planktonic versus biofilm cells ofS. epidermidisby using a rabbit antibody to poly-N-acetylglucosamine (PNAG). These antibodies are opsonic and protect against infection with planktonic cells of PNAG-positiveStaphylococcus aureusandS. epidermidis. Antibody to PNAG readily penetrated the biofilm and bound to the same areas in the biofilm as did wheat germ agglutinin, a lectin known to bind to components of staphylococcal biofilms. However, biofilm cells were more resistant to opsonic killing than their planktonic counterparts in spite of producing more PNAG per cell than planktonic cells. Biofilm extracts inhibited opsonic killing mediated by antibody to PNAG, suggesting that the PNAG antigen within the biofilm matrix prevents antibody binding close to the bacterial cell surface, which is needed for efficient opsonic killing. Increased resistance of biofilm cells to opsonic killing mediated by an otherwise protective antibody was due not to a biofilm-specific phenotype but rather to high levels of antigen within the biofilm that prevented bacterial opsonization by the antibody.
Performance demands of professional male tennis players
Authors: Johnson C D , McHugh M P
Published: July 2006

Objective:To quantify the performance demands in professional male tennis.

Methods:Games from three grand slam tournaments were analysed by an elite tennis player from video recordings. Game related data were collected on 22 players (French Open, 8 (186 games); Wimbledon, 11 (206 games); US Open, 9 (224 games)). Total number of strokes per game was quantified separately for service and return games. Strokes were categorised by type and designated as forehand or backhand. Differences in the types of strokes in a game were analysed using one factor (type of stroke) repeated measures analysis of variance. Differences in total strokes and stroke distributions between playing surfaces were analysed by analysis of variance (surface type) with Tukey’s post hoc pairwise comparisons.

Results:For service games there were more serves per game than any other type of stroke (p<0.001), with topspin forehand and topspin backhand the only other strokes averaging more than one per service game. For return games there were more forehand and backhand returns and topspin forehands and backhands than other types of stroke (p<0.01). Total number of strokes per game was greater in the French Open than Wimbledon (p<0.01), with more topspin forehands (p<0.01) and more topspin backhands (p<0.01). Total strokes per game in the US Open were not different from the other two tournaments.

Conclusions:The serve was the predominant stroke accounting for 45% (French Open) to 60% (Wimbledon) of strokes during service games. The greater number of strokes per game on clayvgrass may contribute to earlier fatigue.
When physiology becomes pathology: the role of magnetic resonance imaging in evaluating bone marrow oedema in the humerus in elite tennis players with an upper limb pain syndrome
Authors: Hoy G , Wood T , Phillips N , Connell D
Published: July 2006

Upper limb stresses are well recognised in tennis, and the normal physiological responses of the humerus to externally applied forces are well defined. Changes to both the microscopic and macroscopic bony architecture are often not apparent on plain radiographs in the early stages of a stress reaction. Bone scintigraphy is more sensitive, but not very specific to subtle changes, as is computer aided tomography. Magnetic resonance imaging (MRI) scans are now used to assess many musculoskeletal injuries, and may allow earlier recognition of changes. This study reports on eight high level tennis players (seven professionals, one highly ranked amateur), who all presented during the course of the 2002 Australian Open and its lead up events. All had an upper limb pain syndrome centred around the elbow. Each underwent an MRI scan. A group of asymptomatic players also had scans of the same area to serve as controls. All symptomatic patients had various levels of bone marrow oedema in their distal humerus, some with periosteal reactions, although most without. No scans revealed a cortical breach. The management of these reactions is problematic in players on an international circuit, as review is sporadic and not always coordinated. The timetabling of international tournaments means it is difficult for top players to obtain adequate rest to avoid injury. Awareness of this early overuse reaction needs to be raised to allow preventive and therapeutic options to be considered to reduce the incidence of this humeral stress response producing an upper limb pain syndrome.
Spontaneous complete hamstring avulsion causing posterior thigh compartment syndrome
Authors: Kwong Y , Patel J
Published: July 2006

Complete avulsion of the hamstring muscle group from its ischial origin is an uncommon condition, and has been mostly reported in young athletes. A case is presented in which a middle aged man sustained this injury and developed a compartment syndrome of the thigh, which has not been previously reported. The surgical management of this patient is described.
Exercise capacity in a 78 year old patient with McArdle’s disease: it is never too late to start exercising
Authors: Perez M , Martin M A , Rubio J C , Maté-Muñoz J L , Gómez-Gallego F , Foster C , Andreu A L , Arenas J , Lucia A
Published: July 2006

The case is reported of a 78 year old man with McArdle’s disease and a history of treated coronary heart disease. Despite the pre-exercise administration of sucrose allowing the patient to exercise with normal physiological responses, and without typical McArdle’s symptoms or biochemical evidence of muscle damage, his exercise capacity was very low (V̇o2peak =  10.7 ml/min/kg), probably attributable to his lifetime of sedentary living. The data suggest that, with pre-exercise sucrose administration, such patients may be candidates for systematic reconditioning, which may improve functional capacity and quality of life.
Messages on the move: the role of the cytoskeleton in mRNA localization and translation in plant cellsThis review is one of a selection of papers published in the Special Issue on Plant Cell Biology.
Authors: Muench Douglas G. , Park Nam-Il
Published: July 2006

The cytoskeleton plays an important role in numerous cellular processes, including subcellular mRNA localization and translation. Several examples of mRNA localization have emerged in plant cells, and these appear to function in protein targeting, the establishment of polarity, and cell-to-cell trafficking. The identification of several cytoskeleton-associated RNA-binding proteins in plant cells has made available candidate proteins that mediate the interaction between mRNA and the cytoskeleton, and possibly play a role in mRNA localization and translational control. We propose a model that links mRNA–microtubule interactions to translational autoregulation, a process that may assist in the efficient and regulated binding of proteins to microtubules.
Nuclear targeting of the cauliflower mosaic virus (CaMV) genomeThis review is one of a selection of papers published in the Special Issue on Plant Cell Biology.
Authors: Champagne Julie , Leclerc Denis
Published: July 2006

The delivery of the double-stranded DNA viral genome into the nucleus is a critical step for the type member of Caulimoviridae, cauliflower mosaic virus (CaMV). The nucleocapsid (NC) of CaMV is directly involved in this process. A nuclear localization signal located at the N-terminus of the NC was shown to be exposed at the surface of the virion. This nuclear localization signal appears to be important to direct the virus to the nuclear pore complex. The nuclear targeting of the NC needs to be tightly regulated because the process of virus assembly, which also involves the viral NC, occurs in the cytosol. It is now accepted that the N- and C-terminal extensions of the viral NC precursor are efficient regulatory sequences that determine the localization of the viral NC in infected leaves. Proteolytic maturation and phosphorylation of the N- and C-terminal extensions are also important in the regulation of this process. Despite these recent discoveries, the transport of CaMV toward and into the nucleus during early events in the infection cycle remains unclear. In this review, we summarize recent advances that explain the mechanisms of targeting of the CaMV genome to the nucleus and extract from other related animal and plant viruses mechanisms that could hint at the possible strategies used by CaMV to enter the nucleus.
Peroxisome biogenesis and the formation of multivesicular peroxisomes during tombusvirus infection: a role for ESCRT?This review is one of a selection of papers published in the Special Issue on Plant Cell Biology.
Authors: Mullen Robert T. , McCartney Andrew W. , Flynn C. Robb , Smith Graham S.T.
Published: July 2006

Peroxisomes are highly dynamic organelles with regard to their metabolic functions, shapes, distribution, movements, and biogenesis. They are also important as sites for the development of some viral pathogens. It has long been known that certain members of the tombusvirus family recruit peroxisomes for viral RNA replication and that this process is accompanied by dramatic changes in peroxisome morphology, the most remarkable of which is the extensive inward vesiculation of the peroxisomal boundary membrane leading to the formation of a peroxisomal multivesicular body (pMVB). While it is unclear how the internal vesicles of a pMVB form, they appear to serve in effectively concentrating viral membrane-bound replication complexes and protecting nascent viral RNAs from host-cell defences. Here, we review briefly the biogenesis of peroxisomes and pMVBs and discuss recent studies that have begun to shed light on how components of the tombusvirus replicase exploit the molecular mechanisms involved in peroxisome membrane protein sorting. We also address the question of what controls invagination and vesicle formation at the peroxisomal membrane during pMVB biogenesis. We propose that tombusviruses exploit protein constituents of the class E vacuolar protein-sorting pathway referred to as ESCRT (endosomal sorting complex required for transport) in the formation of pMVBs. This new pMVB–ESCRT hypothesis reconciles current paradigms of pMVB biogenesis with the role of ESCRT in endosomal multivesicular body formation and the ability of enveloped RNA viruses, including HIV, to appropriate the ESCRT machinery to execute their budding programme from cells.
Protein import into chloroplasts: an ever-evolving storyThis review is one of a selection of papers published in the Special Issue on Plant Cell Biology.
Authors: Smith Matthew D.
Published: July 2006

Chloroplasts are but one type of a diverse group of essential organelles that distinguish plant cells and house many critical biochemical pathways, including photosynthesis. The biogenesis of plastids is essential to plant growth and development and relies on the targeting and import of thousands of nuclear-encoded proteins from the cytoplasm. The import of the vast majority of these proteins is dependent on translocons located in the outer and inner envelope membranes of the chloroplast, termed the Toc and Tic complexes, respectively. The core components of the Toc and Tic complexes have been identified within the last 12 years; however, the precise functions of many components are still being elucidated, and new components are still being identified. In Arabidopsis thaliana (and other species), many of the components are encoded by more than one gene, and it appears that the isoforms differentially associate with structurally distinct import complexes. Furthermore, it appears that these complexes represent functionally distinct targeting pathways, and the regulation of import by these separate pathways may play a role in the differentiation and specific functions of distinct plastid types during plant growth and development. This review summarizes these recent discoveries and emphasizes the mechanisms of differential Toc complex assembly and substrate recognition.
Illuminating subcellular structures and dynamics in plants: a fluorescent protein toolboxThis review is one of a selection of papers published in the Special Issue on Plant Cell Biology.
Authors: Dhanoa Preetinder K. , Sinclair Alison M. , Mullen Robert T. , Mathur Jaideep
Published: July 2006

The discovery and development of multicoloured fluorescent proteins has led to the exciting possibility of observing a remarkable array of subcellular structures and dynamics in living cells. This minireview highlights a number of the more common fluorescent protein probes in plants and is a testimonial to the fact that the plant cell has not lagged behind during the live-imaging revolution and is ready for even more in-depth exploration.
The cell biology of wood formation: from cambial divisions to mature secondary xylemThis review is one of a selection of papers published in the Special Issue on Plant Cell Biology.
Authors: Samuels A.L. , Kaneda M. , Rensing K.H.
Published: July 2006

The development of secondary xylem has been studied historically from an anatomical point of view, but recent developments in cell and molecular biology have revitalized this field. An integrated view of cell structure with physiology is emerging for each stage of the developing xylem cells’ lives, from birth in the cambium to programmed cell death. High-quality structural information is essential in building this type of integrated view, but conventional electron microscopy of developing wood cells has been problematic. The importance of adequately preserving cells of the secondary vascular system is illustrated with examples from dormant cambium, cell division, and secondary cell wall deposition. In many cases, contemporary gene expression studies can be viewed in the context of both new structural information and pioneering live cell studies done in the early 1900s to increase our understanding of secondary xylem development.
Plants as factories for production of biopharmaceutical and bioindustrial proteins: lessons from cell biologyThis review is one of a selection of papers published in the Special Issue on Plant Cell Biology.
Authors: Kermode Allison R.
Published: July 2006

Transgenic plants, seeds, and cultured plant cells are potentially one of the most economical systems for large-scale production of recombinant proteins for industrial and pharmaceutical uses. Biochemical, technical, and economic concerns with current production systems have generated enormous interest in developing plants as alternative production systems. However, various challenges must be met before plant systems can fully emerge as suitable, viable alternatives to current animal-based systems for large-scale production of biopharmaceuticals and other products. Aside from regulatory issues and developing efficient methods for downstream processing of recombinant proteins, there are at least two areas of challenge: (1) Can we engineer plant cells to accumulate recombinant proteins to sufficient levels? (2) Can we engineer plant cells to post-translationally modify recombinant proteins so that they are structurally and functionally similar to the native proteins? Attempts to improve the accumulation of a recombinant protein in plant cells require an appreciation of the processes of gene transcription, mRNA stability, processing, and export, and translation initiation and efficiency. Likewise, many post-translational factors must be considered, including protein stability, protein function and activity, and protein targeting. Moreover, we need to understand how the various processes leading from the gene to the functional protein are interdependent and functionally linked. Manipulation of the post-translational processing machinery of plant cells, especially that for N-linked glycosylation and glycan processing, is a challenging and exciting area. The functions of N-glycan heterogeneity and microheterogeneity, especially with respect to protein function, stability, and transport, are poorly understood and this represents an important area of cell biology.
Structural geology of the Penobsquis salt structure: late Bashkirian inversion tectonics in the Moncton Basin, New Brunswick, eastern Canada
Authors: Wilson Paul , White Joseph C , Roulston Brian V
Published: July 2006

This study uses new information acquired from field mapping, mineral exploration boreholes, and seismic reflection profiles to constrain the structural geology, deformation mechanisms, and timing of the Penobsquis salt structure. This information is used to place the development of the salt structure into the context of the tectonic evolution of the Moncton Basin. The Penobsquis salt structure is an elongate salt wall separated from underlying rocks by a mylonitic detachment horizon. It may be divided into two segments: a southwestern asymmetric, southeast-verging structure and a northeastern strongly asymmetric to overturned, southeast-verging structure associated with the Penobsquis fault. An initial low-amplitude salt anticline formed during deposition of the Mabou Group (Serpukhovian time). The salt anticline was modified into a high-amplitude salt wall after deposition of Cumberland Group sediments (early Bashkirian or later). The sense of asymmetry of the Penobsquis salt structure, the presence of thrust faults within the structure, the spatial association of the structure with a major reverse fault in the salt cover, and the temporal association of salt movement and compressional tectonic events suggest that the salt structure developed in response to tectonic contraction during inversion of the Moncton Basin.
The late Quaternary stratigraphic record northwest of Montréal: regional ice-sheet dynamics, ice-stream activity, and early deglacial events
Authors: Ross Martin , Parent Michel , Benjumea Beatriz , Hunter James
Published: July 2006

The Quaternary sediments of previously unstudied buried valleys and sections near Montréal are analyzed and other sites are revisited to further develop the stratigraphic framework of the St. Lawrence Lowland and to establish regional glacial and deglacial models. The southwest-trending buried valleys were investigated by stratigraphic drilling and high-resolution seismic profiling. The Quaternary succession consists, from base to top, of proximal glaciolacustrine sediments, two superposed till sheets (Argenteuil and Oka tills) of inferred Late Wisconsinan age, and Champlain Sea sediments. The glacial sediments of this sequence record an ice advance toward south (Argenteuil Till) followed by an abrupt ice-flow shift toward the southwest (Oka Till). Compositional and geomorphic data indicate that Oka Till is ubiquitous and is associated with a regional set of glacial landforms. The analysis of a regional digital elevation model in combination with published ice-flow indicators shows convergent flow patterns from the OttawaMontréalAdirondack regions toward the Lake Ontario basin. Landforms produced by the inferred ice stream are locally crosscut by southward-trending ice-flow features. Hence southward flow in the upper St. Lawrence Valley seemingly took place in two distinct contexts: (1) during full glacial conditions, as ice margins stood at or near the late glacial maximum limits, and (2) during late deglaciation, as a post-ice stream reequilibration mechanism. Early deglacial events in the study area were also characterized by subglacial meltwater channelling and erosion along the valleys, subaquatic outwash deposition in glacial Lake Candona, and rapid infill of the valleys during the early stages of the ensuing Champlain Sea.
Small shelly fossils from the basal Emigrant Formation (Cambrian, uppermost Dyeran Stage) of Split Mountain, Nevada
Authors: Skovsted Christian B
Published: July 2006

A latest Early Cambrian fauna of helcionelloid molluscs and small shelly fossils from the basal Emigrant Formation of Nevada is described. The fauna is the first of its kind to be described from trilobite-bearing strata in the Great Basin and is well preserved, but of limited diversity. At the specific level the assemblage is largely endemic, but it contains several genera with global distribution in the Lower and Middle Cambrian. Costipelagiella nevadense n.sp. in the fauna is the oldest representative of the widespread, but little known genus Costipelagiella Horný, 1964. Two additional new taxa are described: Anabarella chelata n.sp. and Parkula esmeraldina n.sp.
Structural variation along the Devil's Mountain fault zone, northwestern Washington
Authors: Hayward Nathan , Nedimović Mladen R , Cleary Matthew , Calvert Andrew J
Published: July 2006

The eastern Juan de Fuca Strait is subject to long-term, northsouth-oriented shortening. The observed deformation is interpreted to result from the northward motion of the Oregon block, which is being driven north by oblique subduction of the oceanic Juan de Fuca plate. Seismic data, acquired during the Seismic Hazards Investigation in Puget Sound survey are used, with coincident first-arrival tomographic velocities, to interpret structural variation along the Devil's Mountain fault zone in the eastern Juan de Fuca Strait. The Primary fault of the Devil's Mountain fault zone developed at the northern boundary of the Everett basin, during northsouth-oriented Tertiary compression. Interpretation of seismic reflection data suggests that, based on their similar geometry including the large magnitude of pre-Tertiary basement offset, the Primary fault of the Devil's Mountain fault west of ~122.95°W and the Utsalady Point fault represent the main fault of the Tertiary Devil's Mountain fault zone. The Tertiary Primary fault west of ~122.95°W was probably kinematically linked to faults to the east (Utsalady Point, Devil's Mountain, and another to the south), by an oblique northnortheast-trending transfer zone or ramp. Left-lateral transpression controlled the Quaternary evolution of the Devil's Mountain fault zone. Quaternary Primary fault offsets are smaller to the east of ~122.95°W, suggesting that stress here was in part accommodated by the prevalent oblique compressional structures to the north. Holocene deformation has focussed on the Devil's Mountain, Utsalady Point, and Strawberry Point faults to the east of ~122.8° but has not affected the Utsalady Point fault to the west of ~122.8°W.
ArAr and UPb ages of marble-hosted ruby deposits from central and southeast Asia
Authors: Garnier V , Maluski H , Giuliani G , Ohnenstetter D , Schwarz D
Published: July 2006

To date the formation of ruby deposits and link it to the regional metamorphism associated with Tertiary Himalayan orogenesis, 40Ar39Ar stepwise heating experiments were performed on single grains of phlogopite syngenetic with ruby, and zircon inclusions in ruby and spinel were dated with the UPb method by ion-probe. The ArAr ages of phlogopites associated with ruby are Oligocene (24.7 ± 0.3 Ma) at Jegdalek in Afghanistan; Miocene at Mogok in Myanmar (18.7 ± 0.2 to 17.1 ± 0.2 Ma), at Hunza in Pakistan (10.8 ± 0.3 to 5.4 ± 0.3 Ma), and Chumar in Nepal (5.6 ± 0.4 Ma); and Pliocene (4.6 ± 0.1 Ma) at Ruyil in Nepal. In Vietnam, a zircon included in a ruby from the Quy Chau deposit yielded a 238U206Pb age of 53.8 ± 4.6 Ma, whereas in the Red River shear zone, ruby formed at around 4036 Ma during ductile deformation under peak metamorphic conditions. The ages obtained in this study are in agreement with those previously published for the ruby-bearing metamorphic belts and document extensional tectonics that were active from Afghanistan to Vietnam between the Oligocene and the Pliocene. Ruby-bearing marbles define a high-quality gem belt linked to the high-temperature metamorphism of the Himalayan fold belt that developed during the Tertiary collision of the Indian plate with Asia.
A test of detailed Nd isotope mapping in the Grenville Province: delineating a duplex thrust sheet in the KipawaMattawa region
Authors: Herrell M K , Dickin A P , Morris W A
Published: July 2006

Over sixty new neodymium model ages were determined on orthogneisses from the KipawaMattawa region of the Grenville Province to refine previous Nd isotope mapping work in this area. The combined Nd data sets support a tectonic model involving three major thrust sheets in the Kipawa area, separated by major shear zones. The uppermost sheet is correlated with the Allochthonous Polycyclic Belt, represented in the study area by the Lac Watson nappe, along with two allochthonous klippen. These have Nd model ages < 1.8 Ga, consistent with previous work. Within the underlying Parautochthonous Belt, previous workers identified a second major shear zone, separating rocks with Archean and Proterozoic crystallization ages, respectively. These two thrust sheets also have distinct Nd isotope signatures. The lowermost sheet consists of metamorphosed but otherwise relatively pristine Archean crust with Nd model ages > 2.6 Ga, whereas the overlying sheet consists of magmatically reworked Archean parautochthon with model ages from 1.82.6 Ga. A residual magnetic-field map developed from aeromagnetic data was compared with the terrane boundaries determined from isotopic data. The aeromagnetic data accurately reflect the margin of relatively pristine Archean crust in the study area, but this boundary does not correspond to the Allochthon Boundary Thrust. Instead, this boundary resulted from downcutting of the basal shear zone of the allochthon. This caused décollement of the strongly reworked Archean parautochthon to generate a duplex thrust sheet that was transported northwestwards over pristine Archean crust.
Paleoproterozoic submarine intrabasinal rifting, Baffin Island, Nunavut, Canada: volcanic structure and geochemistry of the Bravo Lake Formation
Authors: Johns Shannon M , Helmstaedt Herwart H , Kyser T Kurtis
Published: July 2006

Rocks of the Bravo Lake Formation on Turtle Back Island and Pillow Island off the western coast of central Baffin Island, Nunavut, represent a well-exposed example of the mafic volcanic and intrusive sequences commonly preserved near the base of Paleoproterozoic intracratonic basins in the Archean Rae and Hearne provinces of the Canadian Shield. The Bravo Lake Formation is composed of relatively undeformed amygdaloidal pillowed flows, radial columnar and tortoise-shell jointed pillows, hydroclastic breccia, extensional partially sheeted dyke swarms, laminated mafic sediments, massive and fragmental flows, and layered and megacrystic intrusions. Volcanic structures and textures imply emplacement in a low-energy shallow (<2 km depth) submarine environment. High-temperature submarine hydrothermal alteration of the Bravo Lake Formation mobilized Ba and Rb and was subsequently followed by dry closed system prograde amphibolite-facies regional metamorphism. Selected immobile trace element and rare-earth element (REE) compositions characterize these rocks as alkali basalt, minor tholeiitic basalt, and minor fractionated intermediate rocks that display significant light REE enrichment and high field-strength element concentrations suggestive of within-plate basalts. The stratigraphic setting, volcanic and intrusive structures, and chemical compositions suggest formation during local strike-slip-related rifting, rather than a mantle plume environment. The Bravo Lake Formation and its correlatives in other Paleoproterozoic intracratonic basins indicate that crustal thinning and the resultant local rifting of continental crust was widespread throughout the Rae and Hearne provinces of the Canadian Shield during the Paleoproterozoic.
A hierarchical model for salmon run reconstruction and application to the Bristol Bay sockeye salmon (Oncorhynchus nerka) fishery
Authors: Flynn Lucy , Punt André E , Hilborn Ray
Published: July 2006

The goal of spreading the annual catch of a Pacific salmon (Oncorhynchus spp.) run proportionally across all segments of the migration is rendered difficult or impossible because of the interannual variability in both run size and run timing. This problem is particularly acute in the case of the fishery for sockeye salmon (Oncorhynchus nerka) in Bristol Bay, Alaska, for which traditional run reconstruction models are not applicable because of the extreme temporal compression of the run. We develop a run reconstruction model appropriate for sockeye salmon in Bristol Bay by accounting for the hierarchical structure of the problem and by including process error. Our results indicate that the hierarchical structure is, in fact, not necessary, whereas the process error parameters are needed to fit the data. We suggest further model development without the hierarchical structure, including incorporating in-river test fishing data. The results of our method can be used to address questions regarding environmental or intrinsic drivers of run timing and the possibility of artificial selection on run timing.