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Pulmonary embolism (PE) treatment depends on disease severity and risk of complications. Physician and institutional expertise may influence the use of reperfusion therapy (RT) such as systemic thrombolysis (SL) and catheter-directed interventions (CDI). We aimed to investigate the effects of a consensus-based treatment algorithm (TA) and subsequent implementation of PE response team (PERT) on RT modality choices and patient outcomes. A cohort of PE patients admitted to a tertiary care hospital between 2012 and 2017 was retrospectively evaluated. Demographics, clinical variables, RT selections, and patient outcomes during 3 consecutive 2-year periods (baseline, with TA, and with TA+PERT) were compared. Descriptive statistics were used for data analysis. A total of 1105 PE patients were admitted, and 112 received RT. Use of RT increased from 4.7% at baseline to 8.2% and 16.1% during the TA and TA+PERT periods. The primary RT modality transitioned from CDI to SL, and reduced-dose SL became most common. Treatment selection patterns remained unchanged after PERT introduction. Hospital length of stay decreased from 4.78 to 2.96 and 2.81 days ( P < .001). Most of the hemorrhagic complications were minor, and their rates were similar across all 3 periods and between SL and CDI. No major hemorrhages occurred in patients treated with reduced-dose SL. In conclusion, TA and PERT represent components of a decision support system facilitating treatment modality selection, contributing to improved outcomes, and limiting complications. Treatment algorithm emerged as a factor providing consistency to PERT recommendations.

Isoprene synthase converts dimethylallyl diphosphate to isoprene and appears to be necessary and sufficient to allow plants to emit isoprene at significant rates. Isoprene can protect plants from abiotic stress but is not produced naturally by all plants; for example, Arabidopsis (Arabidopsis thaliana) and tobacco (Nicotiana tabacum) do not produce isoprene. It is typically present at very low concentrations, suggesting a role as a signaling molecule; however, its exact physiological role and mechanism of action are not fully understood. We transformed Arabidopsis with a Eucalyptus globulus isoprene synthase. The regulatory mechanisms of photosynthesis and isoprene emission were similar to those of native emitters, indicating that regulation of isoprene emission is not specific to isoprene-emitting species. Leaf chlorophyll and carotenoid contents were enhanced by isoprene, which also had a marked positive effect on hypocotyl, cotyledon, leaf, and inflorescence growth in Arabidopsis. By contrast, leaf and stem growth was reduced in tobacco engineered to emit isoprene. Expression of genes belonging to signaling networks or associated with specific growth regulators (e.g. gibberellic acid that promotes growth and jasmonic acid that promotes defense) and genes that lead to stress tolerance was altered by isoprene emission. Isoprene likely executes its effects on growth and stress tolerance through direct regulation of gene expression. Enhancement of jasmonic acid-mediated defense signaling by isoprene may trigger a growth-defense tradeoff leading to variations in the growth response. Our data support a role for isoprene as a signaling molecule.

OBJECTIVES The study goal was to concurrently evaluate agreement of a 9-point pulmonary ultrasound protocol and portable chest radiograph with chest CT for localization of pathology to the correct lung and also to specific anatomic lobes among a diverse group of intubated patients with acute respiratory failure. DESIGN Prospective cohort study. SETTING Medical, surgical, and neurologic ICUs at a 670-bed urban teaching hospital. PATIENTS Intubated adults with acute respiratory failure having chest CT and portable chest radiograph performed within 24 hours of intubation. INTERVENTIONS A 9-point pulmonary ultrasound examination performed at the time of intubation. MEASUREMENTS AND MAIN RESULTS Sixty-seven patients had pulmonary ultrasound, portable chest radiograph, and chest CT performed within 24 hours of intubation. Overall agreement of pulmonary ultrasound and portable chest radiograph findings with correlating lobe ("lobe-specific" agreement) on CT was 87% versus 62% (p < 0.001), respectively. Relaxing the agreement definition to a matching CT finding being present anywhere within the correct lung ("lung-specific" agreement), not necessarily the specific mapped lobe, showed improved agreement for both pulmonary ultrasound and portable chest radiograph respectively (right lung: 92.5% vs 65.7%; p < 0.001 and left lung: 83.6% vs 71.6%; p = 0.097). The highest lobe-specific agreement was for the finding of atelectasis/consolidation for both pulmonary ultrasound and portable chest radiograph (96% and 73%, respectively). The lowest lobe-specific agreement for pulmonary ultrasound was normal lung (79%) and interstitial process for portable chest radiograph (29%). Lobe-specific agreement differed most between pulmonary ultrasound and portable chest radiograph for interstitial findings (86% vs 29%, respectively). Pulmonary ultrasound had the lowest agreement with CT for findings in the left lower lobe (82.1%). Pleural effusion agreement also differed between pulmonary ultrasound and portable chest radiograph (right: 99% vs 87%; p = 0.009 and left: 99% vs 85%; p = 0.004). CONCLUSIONS A clinical, 9-point pulmonary ultrasound protocol strongly agreed with specific CT findings when analyzed by both lung- and lobe-specific location among a diverse population of mechanically ventilated patients with acute respiratory failure; in this regard, pulmonary ultrasound significantly outperformed portable chest radiograph.

Plants with facultative crassulacean acid metabolism (CAM) maximize performance through utilizing C3 or C4 photosynthesis under ideal conditions while temporally switching to CAM under water stress (drought). While genome-scale analyses of constitutive CAM plants suggest that time of day networks are shifted, or phased to the evening compared to C3, little is known for how the shift from C3 to CAM networks is modulated in drought induced CAM. Here we generate a draft genome for the drought-induced CAM-cycling species Sedum album. Through parallel sampling in well-watered (C3) and drought (CAM) conditions, we uncover a massive rewiring of time of day expression and a CAM and stress-specific network. The core circadian genes are expanded in S. album and under CAM induction, core clock genes either change phase or amplitude. While the core clock cis-elements are conserved in S. album, we uncover a set of novel CAM and stress specific cis-elements consistent with our finding of rewired co-expression networks. We identified shared elements between constitutive CAM and CAM-cycling species and expression patterns unique to CAM-cycling S. album. Together these results demonstrate that drought induced CAM-cycling photosynthesis evolved through the mobilization of a stress-specific, time of day network, and not solely the phasing of existing C3 networks. These results will inform efforts to engineer water use efficiency into crop plants for growth on marginal land., Author summary Crassulacean acid metabolism (CAM) photosynthesis represents an important adaptation to arid environments as CAM plants take up CO2 at night when evapotranspiration rates are lower. Genomes and large-scale datasets are available for several plants with constitutive CAM activity, but they provided little insight on how this trait evolved from C3. Here we sequenced the CAM-cycling plant Sedum album, which switches from C3 to CAM photosynthesis under drought conditions. We performed a global gene expression analysis sampling every two hours over 24 hours in C3 (well-watered) and CAM (drought) conditions. This comparative approach allowed us to identify components of the CAM pathway that were previously unidentified in constitutive CAM plants such as pineapple and orchid. Our results reveal a massive time of day specific rewiring of the transcriptional networks in Sedum where only 20% of cycling genes overlap between the C3 and CAM conditions. This time of day reprogramming results in broad network changes linking stress pathways and photosynthesis under CAM.

The oxygenation of ribulose 1,5-bisphosphate by Rubisco is the first step in photorespiration and reduces the efficiency of photosynthesis in C(3) plants. Our recent data indicate that mutants in photorespiration have increased rates of photosynthetic cyclic electron flow around photosystem I. We investigated mutant lines lacking peroxisomal hydroxypyruvate reductase to determine if there are connections between 2-phosphoglycolate accumulation and cyclic electron flow in Arabidopsis (Arabidopsis thaliana). We found that 2-phosphoglycolate is a competitive inhibitor of triose phosphate isomerase, an enzyme in the Calvin-Benson cycle that converts glyceraldehyde 3-phosphate to dihydroxyacetone phosphate. This block in metabolism could be overcome if glyceraldehyde 3-phosphate is exported to the cytosol, where cytosolic triose phosphate isomerase could convert it to dihydroxyacetone phosphate. We found evidence that carbon is reimported as glucose-6-phosphate, forming a cytosolic bypass around the block of stromal triose phosphate isomerase. However, this also stimulates a glucose-6-phosphate shunt, which consumes ATP, which can be compensated by higher rates of cyclic electron flow.

The oxygenation of ribulose 1,5-bisphosphate by Rubisco is the first step in photorespiration and reduces the efficiency of photosynthesis in C3plants. Our recent data indicates that mutants in photorespiration have increased rates of photosynthetic cyclic electron flow around photosystem I. We investigated mutant lines lacking peroxisomal hydroxypyruvate reductase to determine if there are connections between 2-PG accumulation and cyclic electron flow. We found that 2-PG is a competitive inhibitor of triose phosphate isomerase (TPI), an enzyme in the Calvin-Benson cycle that converts glyceraldehyde 3-phosphate to dihydroxyacetone phosphate. This block in metabolism could be overcome if glyceraldehyde 3-phosphate is exported to the cytosol where the cytosolic triose phosphate isomerase could convert it to dihydroxyacetone phosphate. We found evidence that carbon is reimported as Glc-6P-phosphate forming a cytosolic bypass around the block of stromal TPI. However, this also stimulates a Glc-6P-phosphate shunt, which consumes ATP, which can be compensated by higher rates of cyclic electron flow.Once Sentence SummaryTriose phosphate isomerase is inhibited in plants lacking hydroxypyruvate reductase 1 and this is overcome by exporting triose phosphate to the cytosol and importing Glc-6P, which stimulates a Glc-6P-phosphate shunt and cyclic electron flow.

The triose phosphate use limitation was studied using long-term and short term changes in capacity. The TPU limitation caused increased proton motive force; long-term TPU limitation additionally reduced other photosynthetic components. Photosynthetic responses to CO2 can be interpreted primarily as being limited by the amount or activity of Rubisco or the capacity for ribulose bisphosphate regeneration, but at high rates of photosynthesis a third response is often seen. Photosynthesis becomes insensitive to CO2 or even declines with increasing CO2, and this behavior has been associated with a limitation of export of carbon from the Calvin–Benson cycle. It is often called the triose phosphate use (TPU) limitation. We studied the long-term consequences of this limitation using plants engineered to have reduced capacity for starch or sucrose synthesis. We studied short-term consequences using temperature as a method for changing the balance of carbon fixation capacity and TPU. A long-term and short-term TPU limitation resulted in an increase in proton motive force (PMF) in the thylakoids. Once a TPU limitation was reached, any further increases in CO2 was met with a further increase in the PMF but no increase or little increase in net assimilation of CO2. A long-term TPU limitation resulted in reduced Rubisco and RuBP regeneration capacity. We hypothesize that TPU, Rubisco activity, and RuBP regeneration are regulated so that TPU is normally in slight excess of what is required, and that this results in more effective regulation than if TPU were in large excess.

Photosynthetic cells of most land plant lineages have numerous small chloroplasts even though most algae, and even the early diverging land plant group the hornworts, tend to have one or a few large chloroplasts. One constraint that small chloroplasts could improve is the resistance to CO2 diffusion from the atmosphere to the chloroplast stroma. We examined the mesophyll conductance (inverse of the diffusion resistance) of mutant Arabidopsis thaliana plants with one or only a few large chloroplasts per cell. The accumulation and replication of chloroplasts (arc) mutants of A. thaliana were studied by model fitting to gas exchange data and 13CO2 discrimination during carbon fixation. The two methods generally agreed, but the value of the CO2 compensation point of Rubisco (Γ *) used in the model had a large impact on the estimated photosynthetic parameters, including mesophyll conductance. We found that having only a few large chloroplasts per cell resulted in a 25–50 % reduction in the mesophyll conductance at ambient CO2.

An effect of an axial current on the propagation of low-frequency axisymmetric magnetohydroclynamic waves in a radially non-uniform plasma column was investigated theoretically and experimentally. It was found that the axial current and the density gradient cause a coupling between the torsional and compressional waves.

The key enzyme for C4 photosynthesis, Phosphoenolpyruvate Carboxylase (PEPC), evolved from nonphotosynthetic PEPC found in C3 ancestors. In all plants, PEPC is phosphorylated by Phosphoenolpyruvate Carboxylase Protein Kinase (PPCK). However, differences in the phosphorylation pattern exist among plants with these photosynthetic types, and it is still not clear if they are due to interspecies differences or depend on photosynthetic type. The genus Flaveria contains closely related C3, C3-C4 intermediate, and C4 species, which are evolutionarily young and thus well suited for comparative analysis. To characterize the evolutionary differences in PPCK between plants with C3 and C4 photosynthesis, transcriptome libraries from nine Flaveria spp. were used, and a two-member PPCK family (PPCKA and PPCKB) was identified. Sequence analysis identified a number of C3- and C4-specific residues with various occurrences in the intermediates. Quantitative analysis of transcriptome data revealed that PPCKA and PPCKB exhibit inverse diel expression patterns and that C3 and C4 Flaveria spp. differ in the expression levels of these genes. PPCKA has maximal expression levels during the day, whereas PPCKB has maximal expression during the night. Phosphorylation patterns of PEPC varied among C3 and C4 Flaveria spp. too, with PEPC from the C4 species being predominantly phosphorylated throughout the day, while in the C3 species the phosphorylation level was maintained during the entire 24 h. Since C4 Flaveria spp. evolved from C3 ancestors, this work links the evolutionary changes in sequence, PPCK expression, and phosphorylation pattern to an evolutionary phase shift of kinase activity from a C3 to a C4 mode.

Summary A new understanding of leaf starch degradation has emerged in the last 10 years. It has been shown that starch phosphorylation and dephosphorylation are critical components of this process. Glucan, water dikinase (GWD) (and phosphoglucan, water dikinase) adds phosphate to starch, and phosphoglucan phosphatase (SEX4) removes these phosphates. To explore the use of this metabolism to manipulate starch accumulation, Arabidopsis (Arabidopsis thaliana) plants were engineered by introducing RNAi constructs designed to reduce expression of AtGWD and AtSEX4. The timing of starch build-up was altered with ethanol-inducible and senescence-induced gene promoters. Ethanol induction of RNAi lines reduced transcript for AtGWD and AtSEX4 by 50%. The transgenic lines had seven times more starch than wild type at the end of the dark period but similar growth rates and total biomass. Elevated leaf starch content in maize leaves was engineered by making an RNAi construct against a gene in maize that appeared to be homologous to AtGWD. The RNAi construct was expressed using the constitutive ubiquitin promoter. Leaf starch content at the end of a night period in engineered maize plants was 20-fold higher than in untransformed plants with no impact on total plant biomass. We conclude that plants can be engineered to accumulate starch in the leaves with little impact on vegetative biomass.

Essentially all plants store starch in their leaves during the day and break it down the following night. This transitory starch accumulation acts as an overflow mechanism when the sucrose synthesis capacity is limiting, and transitory starch also acts as a carbon store to provide sugar at night. Transitory starch breakdown can occur by either of two pathways; significant progress has been made in understanding these pathways in C(3) plants. The hydrolytic (amylolytic) pathway generating maltose appears to be the primary source of sugar for export from C(3) chloroplasts at night, whereas the phosphorolytic pathway supplies carbon for chloroplast reactions, in particular in the light. In crassulacean acid metabolism (CAM) plants, the hydrolytic pathway predominates when plants operate in C(3) mode, but the phosphorolytic pathway predominates when they operate in CAM mode. Information on transitory starch metabolism in C(4) plants has now become available as a result of combined microscopy and proteome studies. Starch accumulates in all cell types in immature maize leaf tissue, but in mature leaf tissues starch accumulation ceases in mesophyll cells except when sugar export from leaves is blocked. Proper regulation of the amount of carbon that goes into starch, the pathway of starch breakdown, and the location of starch accumulation could help ensure that engineering of C(4) metabolism is coordinated with the downstream reactions required for efficient photosynthesis.

Increasing the energy density of biomass by engineering the accumulation of triacylglycerols (TAGs) in vegetative tissues is synergistic with efforts to produce biofuels by conversion of lignocellulosic biomass. Typically, TAG accumulates in developing seeds, and little is known about the regulatory mechanisms and control factors preventing oil biosynthesis in vegetative tissues in most plants. Here, we engineered Arabidopsis thaliana to ectopically overproduce the transcription factor WRINKLED1 (WRI1) involved in the regulation of seed oil biosynthesis. Furthermore, we reduced the expression of APS1 encoding a major catalytic isoform of the small subunit of ADP-glucose pyrophosphorylase involved in starch biosynthesis using an RNAi approach. The resulting AGPRNAi-WRI1 lines accumulated less starch and more hexoses. In addition, these lines produced 5.8-fold more oil in vegetative tissues than plants with WRI1 or AGPRNAi alone. Abundant oil droplets were visible in vegetative tissues. TAG molecular species contained long-chain fatty acids, similar to those found in seed oils. In AGPRNAi-WRI1 lines, the relative expression level of sucrose synthase 2 was considerably elevated and correlated with the level of sugars. The relative expression of the genes encoding plastidic proteins involved in de novo fatty acid synthesis, biotin carboxyl carrier protein isoform 2 and acyl carrier protein 1, was also elevated. The relative contribution of TAG compared to starch to the overall energy density increased 9.5-fold in one AGPRNAi-WRI1 transgenic line consistent with altered carbon partitioning from starch to oil.

Zusammenfassung 1 Mit Hilfe der Agglutination-Lysis-Reaktion wurden 86 (10,6%) von 813 Rindern als leptospirosepositiv bewertet. Besonders haufig reagierten mit L. grippotyphosa Tiere aus Bayern. 2 Versuche, aus 59 Nieren von tauglich beurteilten Rindern Leptospiren zu isolieren, hatten ein negatives Ergebnis. 3 Makroskopisch wurden in der Rinde von 21 der 59 Nieren Zysten — meist stecknadelkopfgros — gefunden. Auf der Oberflache von 2 Nieren waren kleine grauweise Herdchen sichtbar. Bei der histologischen Untersuchung ergab sich, das die Mehrzahl der Nieren m. o. w. stark ausgepragte Zellinfiltrate (Lymphozyten, Histiozyten) enthielt. 4 Die fluoreszenzmikroskopischen Untersuchungen verliefen negativ. 5 Ein Zusammenhang der pathologisch-anatomischen Veranderungen mit den serologischen und kulturellen Ergebnissen war nicht festzustellen. Fur die technische Mitarbeit danken wir Frl. I. Lehmann und Frl. U. Kroehling. Summary Serological, cultural and histological studies on slaughter cattle with leptospirosis 1 Using the agglutination-lysis test, 86 (10.6%) of 813 cattle were positive for leptospirosis. Animals from Bavaria reacted particularly often to L. grippotyphosa. 2 Attempts to isolate leptospira from 59 kidneys from animals suspected of leptospirosis were all negative. 3 Macroscopically the cortex of 21 of the 59 kidneys showed cysts, usually of pinhead size. The surface of two kidneys showed small greyish-white foci. Most of the kidneys showed cellular infiltration of varying extent with lymphocytes and histiocytes. 4 Studies by fluorescent microscopy gave negative results. 5 It was not possible to establish a relationship between the pathological findings and the serological and cultural results. Resume Recherches serologiques, culturelles et histologiques sur la leptospirose chez les boeufs d'abattage A l'aide de la reaction de lyse-agglutination, pratiquee sur 813 bovins, on a trouve 86 cas leptospires-positifs (10%). Le plus souvent, ce sont des animaux de Baviere qui reagissent avec L. grippotyphosa. Les tentatives pour isoler des leptospires a partir de 59 reins de bovins estimes sains s'avererent negatives. Dans 21 de ces reins, on a trouve dans le cortex des kystes d'ordre macroscopique, le plus souvent de la grosseur d'une tete d'epingle. A la surface de 2 reins, on a pu voir de petits foyers gris clairs. A l'examen histologique, la plupart de ces reins apparurent plus ou moins infiltres de cellules (lymphocytes, histiocytes). Les examens au microscope a fluorescence ont donne des resultats negatifs. On n'a pas pu etablir de relations entre les lesions anatomo-pathologiques et les resultats de la serologie et des cultures. Resumen Estudios serologicos, culturales e histologicos en reses vacunas sacrificadas acerca de la leptospirosis Con ayuda de la reaccion de lisis de la aglutinacion se valoraron 86 (10,6%) de 813 reses vacunas como positivas de leptospirosis. Con frecuencia extraordinaria reaccionaban con L. grippotyphosa los animales procedentes de Baviera. Los ensayos, que tenian por fin aislar leptospiras a partir de 59 rinones de reses bovinas calificadas aptas para el consumo, tuvieron un resultado negativo. Macroscopicamente se hallaron quistes — casi siempre del tamano de la cabeza de un alfiler — en la corteza de 21 de los 59 rinones. En la superficie de 2 rinones se veian foquitos blancogrisaceos. El examen histopatologico arrojo que la mayoria de los rinones contenia infiltraciones celulares manifiestas (linfocitos e histiocitos). Los estudios fluorescentemicroscopicos resultaron negativos. No se pudo establecer relacion alguna entre las alteraciones anatomopatologicas y los resultados serologicos y culturales.

A putative phosphatase, LSF1 (for LIKE SEX4; previously PTPKIS2), is closely related in sequence and structure to STARCH-EXCESS4 (SEX4), an enzyme necessary for the removal of phosphate groups from starch polymers during starch degradation in Arabidopsis (Arabidopsis thaliana) leaves at night. We show that LSF1 is also required for starch degradation: lsf1 mutants, like sex4 mutants, have substantially more starch in their leaves than wild-type plants throughout the diurnal cycle. LSF1 is chloroplastic and is located on the surface of starch granules. lsf1 and sex4 mutants show similar, extensive changes relative to wild-type plants in the expression of sugar-sensitive genes. However, although LSF1 and SEX4 are probably both involved in the early stages of starch degradation, we show that LSF1 neither catalyzes the same reaction as SEX4 nor mediates a sequential step in the pathway. Evidence includes the contents and metabolism of phosphorylated glucans in the single mutants. The sex4 mutant accumulates soluble phospho-oligosaccharides undetectable in wild-type plants and is deficient in a starch granule-dephosphorylating activity present in wild-type plants. The lsf1 mutant displays neither of these phenotypes. The phenotype of the lsf1/sex4 double mutant also differs from that of both single mutants in several respects. We discuss the possible role of the LSF1 protein in starch degradation.

The COMPASS experiment makes use of the CERN SPS high-intensitymuon and hadron beams for the investigation of the nucleon spin structure and the spectroscopy of hadrons. One or more outgoing particles are detected in coincidence with the incoming muon or hadron. A large polarized target inside a superconducting solenoid is used for the measurements with the muon beam. Outgoing particles are detected by a two-stage, large angle and large momentum range spectrometer. The setup is built using several types of tracking detectors, according to the expected incident rate, required space resolution and the solid angle to be covered. Particle identification is achieved using a RICH counter and both hadron and electromagnetic calorimeters. The setup has been successfully operated from 2002 onwards using a muon beam. Data with a hadron beam were also collected in 2004. This article describes the main features and performances of the spectrometer in 2004; a short summary of the 2006 upgrade is also given., 84 papes, 74 figures

We present a precise measurement of the deuteron longitudinal spin asymmetry A 1 d and of the deuteron spin-dependent structure function g 1 d at Q 2 1 ( GeV / c ) 2 and 4 × 10 −5 x 2.5 × 10 −2 based on the data collected by the COMPASS experiment at CERN during the years 2002 and 2003. The statistical precision is tenfold better than that of the previous measurement in this region. The measured A 1 d and g 1 d are found to be consistent with zero in the whole range of x.

The epidemiology of infectious foodborne diseases has changed. Outbreaks more frequently occur geographically dispersed or protractedly over longer periods of time, and they often appear as a scatter of seemingly sporadic cases. This hampers and delays the identification of their epidemiological link. The surveillance of infectious foodborne diseases has to be refined accordingly to be able to detect these diffuse outbreaks. The German Protection against Infection Act, enacted in 2001, offers the potential of increased sensitivity due to timely electronic reporting of individual cases and detailed data accompanying each report. In addition to a timely and comprehensive reporting system, subtyping of pathogens has become an invaluable tool in identifying epidemiologically linked cases, i.e. outbreaks. Still, the sensitivity of foodborne disease surveillance still hinges on the willingness of physicians to order stool testing for enteric pathogens (and to report suspected outbreaks to local health departments). Without the active participation of physicians, the chance of detecting outbreaks and successfully investigating them is markedly reduced. Consequently, the general preventive strategy would be jeopardised, namely to understand the (often new) mechanisms by which contamination and disease transmission occur well enough to interrupt them.

Transitory starch is formed in chloroplasts during the day and broken down at night. Transitory starch degradation could be regulated by light, circadian rhythms, or carbon balance. To test the role of these potential regulators, starch breakdown rates and metabolites were measured in bean (Phaseolus vulgaris) and Arabidopsis (Arabidopsis thaliana) plants. In continuous light, starch and maltose levels oscillated in a circadian manner. Under photorespiratory conditions, transitory starch breakdown occurred in the light faster than at night and glucose-6-P (G6P) was elevated. Nonaqueous fractionation showed that the increase in G6P occurred in the chloroplast. When Arabidopsis plants lacking the plastidic starch phosphorylase enzyme were placed under photorespiratory conditions, G6P levels remained constant, indicating that the increased chloroplastic G6P resulted from phosphorolytic starch degradation. Maltose was increased under photorespiratory conditions in both wild type and plants lacking starch phosphorylase, indicating that regulation of starch breakdown may occur at a point preceding the division of the hydrolytic and phosphorolytic pathways. When bean leaves were held in N2 to suppress photosynthesis and Suc synthesis without increasing photorespiration, starch breakdown did not occur and maltose and G6P levels remained constant. The redox status of the chloroplasts was found to be oxidized under conditions favoring starch degradation.

Maltose is the predominant form of carbon exported from the chloroplast at night. Plants that lack either the chloroplast maltose transporter or disproportionating enzyme 2 (DPE2, EC 2.4.1.25) have excess maltose in leaves. We confirmed that DPE2 is not associated with the chloroplast in Arabidopsis thaliana. Using non-aqueous fractionation methods, we found that essentially all the maltose in mex1-1 leaves is located inside chloroplasts but only 40% of maltose in dpe2-1 leaves is located inside chloroplasts. We found that maltose exists in a significant amount in the exudates collected from maltose-accumulating dpe2-1 Arabidopsis petioles. However, the amount of maltose in the exudates from mex1-1 petioles was not significantly different from that in wild-type phloem exudates. We found twice as much maltose in the roots of dpe2-1 plants relative to wild type but the maltose level in the roots of mex1-1 plants was not higher than wild type. We conclude that maltose accumulated in the cytosol of leaves can be carried from the shoots to the roots and that maltose accumulated in the chloroplast of mex1-1 leaves is not mobilized. By measuring the transcript levels and enzymatic activities, we show that maltose-metabolizing enzymes are active in wild-type roots. The amount of maltose moved from the shoots to the roots increased in dpe2-1 plants. The roots of dpe2-1 plants must have the capacity to metabolize the excess maltose.

We present a determination of the gluon polarization Δ G / G in the nucleon, based on the helicity asymmetry of quasi-real photoproduction events, Q 2 1 ( GeV / c ) 2 , with a pair of large transverse-momentum hadrons in the final state. The data were obtained by the COMPASS experiment at CERN using a 160 GeV polarized muon beam scattered on a polarized 6 LiD target. The helicity asymmetry for the selected events is 〈 A ∥ / D 〉 = 0.002 ± 0.019 ( stat ) ± 0.003 ( syst ) . From this value, we obtain in a leading-order QCD analysis Δ G / G = 0.024 ± 0.089 ( stat ) ± 0.057 ( syst ) at x g = 0.095 and μ 2 ≃ 3 ( GeV / c ) 2 .

SUMMARY We have developed a miniaturized very high frequency (VHF) transmitter design for radio-tagging small animals. The average mass of the circuitry is 0.084 g (range 0.081-0.087), hence, with the smallest power cell, complete tags weigh 0.2 g and have a life of 18-22 days. We further demonstrate that with such small tags the technique of attaching the device to the animal's body strongly affects the effective radiated power, and thus transmission ranges. Ideally the attachment couples the electronics to the animal's body as a ground plane for improved radiation. The transmitter allows the application of radio-tracking to be expanded to new taxa whose spatial behaviour and population dynamics are largely unknown, for example arthropods, reptiles or amphibians. The new design is also suitable for miniature implants and signal modulation with sensors.

Maltose is the major form of carbon exported from the chloroplast at night as a result of transitory starch breakdown. Maltose exists as an α- or β-anomer. We developed an enzymatic technique for distinguishing between the two anomers of maltose and tested the accuracy and specificity of this technique using β-maltose liberated from maltoheptose by β-amylase. This technique was used to investigate which form of maltose is present during transitory starch degradation in bean (Phaseolus vulgaris), wild-type Arabidopsis (Arabidopsis thaliana), two starch deficient Arabidopsis lines, and one starch-excess mutant of Arabidopsis. In Phaseolus and wild-type Arabidopsis, β-maltose levels were low during the day but were much higher at night. In Arabidopsis plants unable to metabolize maltose due to a T-DNA insertion in the gene for the cytosolic amylomaltase, (Y. Lu, T.D. Sharkey [2004] Planta 218: 466–473) levels of α- and β-maltose were high during both the day and night. In starchless mutants of Arabidopsis, total maltose levels were low and almost completely in the α-form. We also found that the subcellular concentration of β-maltose at night was greater in the chloroplast than in the cytosol by 278 μ m. We conclude that β-maltose is the metabolically active anomer of maltose and that a sufficient gradient of β-maltose exists between the chloroplast and cytosol to allow for passive transport of maltose out of chloroplasts at night.

Transitory starch is formed in chloroplasts during the day and broken down at night. We investigated carbon export from chloroplasts resulting from transitory-starch breakdown. Starch-filled chloroplasts from spinach ( Spinacia oleracea L. cv. Nordic IV) were isolated 1 h after the beginning of the dark period and incubated for 2.5 h, followed by centrifugation through silicone oil. Exported products were measured in the incubation medium to avoid measuring compounds retained inside the chloroplasts. Maltose and glucose made up 85% of the total exported products and were exported at rates of 626 and 309 nmol C mg(-1) chlorophyll h(-1), respectively. Net export of phosphorylated products was less than 5% and higher maltodextrins were not detected. Maltose levels in leaves of bean ( Phaseolus vulgaris L. cv. Linden), spinach, and Arabidopsis thaliana (L.) Heynh. were low in the light and high in the dark. Maltose levels remained low and unchanged during the light/dark cycle in two starch-deficient Arabidopsis mutants, stf1, deficient in plastid phosphoglucomutase, and pgi, deficient in plastid phosphoglucoisomerase. Through the use of nonaqueous fractionation, we determined that maltose was distributed equally between the chloroplast and cytosolic fractions during darkness. In the light there was approximately 24% more maltose in the cytosol than the chloroplast. Taken together these data indicate that maltose is the major form of carbon exported from the chloroplast at night as a result of starch breakdown. We hypothesize that the hydrolytic pathway for transitory-starch degradation is the primary pathway used when starch is being converted to sucrose and that the phosphorolytic pathway provides carbon for other purposes.

At the Cooler-Synchrotron COSY/Julich polarized and unpolarized elastic proton-proton scattering has been investigated with the EDDA-Experiment in the energy range (T p ≈ 0.5−2.5 GeV). By taking scattering data during the acceleration of the beam with a large-acceptance (θ c.m. ≈ 30°−90°) detector, precise excitation functions for differential cross-section and analyzing power have been measured in small energy steps with consistent normalization with respect to luminosity and polarization. These data have helped to improve the determination of phase-shifts at higher energies and impose tight quantitative upper bounds on possible resonant contributions to pp elastic scattering, as they might arise from exotic 6-quark configurations. Recently, with polarized beam and target, the spin-correlation parameters A NN, A SS, and A SL have been determined at 10 energies between 0.8 and 2.5 GeV. The observable Ass has been measured the first time above 800 MeV and our results are in sharp contrast to phase-shift predictions at higher energies.

Isoprene (C 5 H 8 ) is emitted from many plants and has a substantial effect on atmospheric chemistry. There are several models to estimate the rate of isoprene emission used to calculate the impact of isoprene on atmospheric processes. The rate of isoprene synthesis will depend either on the activity of isoprene synthase or the availability of its substrate dimethylallyl pyrophosphate (DMAPP). To investigate long-term regulation of isoprene synthesis, the isoprene emission rate of 15 kudzu leaves was measured. The chloroplast DMAPP level of the five leaves with the highest emission rates and the five leaves with the lowest rates were determined by non-aqueous fractionation of the bulked leaf samples. Leaves with high basal emission rates had low levels of DMAPP whereas leaves with low basal emission rates had high DMAPP levels in their chloroplasts indicating that the activity of isoprene synthase exerts primary control over the basal emission rate. To investigate short-term regulation, isoprene precursors were fed to leaves. Feeding dideuterated deoxyxylulose (DOX-d 2 ) to Eucalyptus leaves resulted in the emission of dideuterated isoprene. Results from DOX-d 2 feeding experiments indicated that control of isoprene emission rate was shared between reactions upstream and downstream of the DOX entry into isoprene metabolism. In CO 2 -free air DOX always increased isoprene emission indicating that carbon availability was an important control factor. In N 2 , isoprene emission stopped and could not be recovered by adding DOX-d 2 . Taken together, these results indicate that the regulation of isoprene emission is shared among several steps and the relative importance of the different steps in controlling isoprene emission varies with conditions.

Excitation functions of the differential cross sections dσ dgw , analyzing powers AN and spin correlation parameters ANN, ASS and ASL have been measured with internal targets at the Cooler Synchrotron COSY. Data were taken continously during the acceleration and deceleration of the internal beam for kinetic energies between 450 and 2500 MeV and scattering angles 30° ⩽ σcm ⩽ 90°. Details of the experimental method are presented. The results provide excitation functions and angular distributions of high precision and internal consistency. No evidence for narrow structures are found. Upper limits on the coupling of narrow resonances to elastic scattering in the mass range √s = 2.2…2.8 GeV are deduced. The data have significant impact on phase shift solutions.

Excitation functions A(N)(p(p),Theta(c.m.)) of the analyzing power in pp--> elastic scattering have been measured with a polarized atomic hydrogen target for projectile momenta p(p) between 1000 and 3300 MeV/ c. The experiment was performed for scattering angles 30 degrees

Many people think of plants as essentially sessile organisms that do not actively respond to their environment. What could be further from the truth! In fact, plants are capable of a variety of movements, including the dramatic nastic responses (such as Venus fly trap closure) and the less sensational tropisms. These latter movements are directed growth responses to some type of external stimulus such as gravity (gravitropism, formerly known as geotropism) or light (phototropism). This paper describes some interesting exercises that are derived from recent work, including research that has led to experiments performed on two Space Shuttle missions in 1997 (Kiss et al. 1998). The study of tropisms can be a useful way to introduce students to plant biology in high school and introductory college courses. In our experience, students are fascinated by plant movements when they are presented in lectures and find laboratory experiences on this topic quite engaging. Laboratory work on plant tropisms can also be used to introduce important concepts in science such as hypothesis testing, quantitative analysis, and the use of statistics. The laboratory exercises described in this paper involve the higher plant Arabidopsis thaliana, which has become an important organism in molecular biology research and is the focus of an international plant genome project. Based on the material presented here, a number of plant gravitropism laboratory exercises with Arabidopsis that are simple in terms of equipment/materials and procedures can be developed. These exercises are robust in that they work well even in the hands of introductory students, and they can be expanded according to the individual instructor's needs. This paper describes two exercises that have been performed by beginning college students, and these exercises can easily be performed in biology classes in most high school settings.

We present a measurement of the deuteron spin-dependent structure function g1d based on the data collected by the COMPASS experiment at CERN during the years 2002-2004. The data provide an accurate evaluation for Gamma_1^d, the first moment of g1d(x), and for the matrix element of the singlet axial current, a0. The results of QCD fits in the next to leading order (NLO) on all g1 deep inelastic scattering data are also presented. They provide two solutions with the gluon spin distribution function Delta G positive or negative, which describe the data equally well. In both cases, at Q^2 = 3 (GeV/c)^2 the first moment of Delta G is found to be of the order of 0.2 - 0.3 in absolute value., Comment: fits redone using MRST2004 instead of MRSV1998 for G(x), correlation matrix added

A novel scintillating fiber hodoscope in helically cylindric geometry has been developed for detection of low multiplicity events of fast protons and other light charged particles in the internal target experiment EDDA at the Cooler Synchrotron COSY. The hodoscope consists of 640 scintillating fibers (2.5 mm diameter), arranged in four layers surrounding the COSY beam pipe. The fibers are helically wound in opposing directions and read out individually using 16-channel photomultipliers connected to a modified commercial encoding system. The detector covers an angular range of 9°⩽ Θ ⩽72° and 0°⩽ ϕ ⩽360° in the lab frame. The detector length is 590 mm, the inner diameter 161 mm. Geometry and granularity of the hodoscope afford a position resolution of about 1.3 mm. The detector design took into consideration a maximum of reliability and a minimum of maintenance. An LED array may be used for monitoring purposes.

Previous studies have assayed the gravitropic response of roots and hypocotyls of wild type Arabidopsis thaliana, two reduced-starch strains, and a starchless strain. Because there have been few reports on inflorescence gravitropism, in this article, we use microscopic analyses and time-course studies of these mutants and their wild type to study gravitropism in these stems. Sedimentation of plastids was observed in endodermal cells of the wild type and reduced-starch mutants but not in the starchless mutant. In all of these strains, the short inflorescence stems (1.0-2.9 cm) were less responsive to the gravistimulus compared with the long stems (3.0-6.0 cm). In both long and short inflorescence stems, the wild type initially had the greatest response; the starchless mutant had the least response; and the reduced starch mutants exhibited an intermediate response. Furthermore, growth rates among all four strains were approximately equal. At about 6 h after reorientation, inflorescences of all strains returned to a position parallel to the gravity vector. Thus, in inflorescence stems, sedimentation of plastids may act as an accelerator but is not required to elicit a gravitropic response. Furthermore, the site of perception appears to be diffuse throughout the inflorescence stem. These results are consistent with both a plastid-based statolith model and the protoplast pressure hypothesis, and it is possible that multiple systems for gravity perception occur in plant cells.

We present a new measurement of the longitudinal spin asymmetry A_1^d and the spin-dependent structure function g_1^d of the deuteron in the range 1 GeV^2 < Q^2 < 100 GeV^2 and 0.004< x, 10 pages, 6 figures, subm. to PLB, revised: author list, Fig. 4, details added

Excitation functions of proton-proton elastic cross sections have been measured in narrow momentum steps Δp = 28 MeV/c in the kinetic energy range from 0.5 to 2.5 GeV and the angular range 35° ≤ Θ cm ≤ 90° with a detector providing ΔΘ cm ≈ 1.4° resolution and 82% solid angle coverage. Measurements have been performed continuously during projectile acceleration in the Cooler Synchrotron COSY with an internal CH 2 fiber target; background corrections were derived from measurements with a carbon fiber target and from Monte Carlo simulations of inelastic pp contributions. Particular care was taken to monitor the luminosity as a function of beam energy. The results provide excitation functions and angular distributions of unprecedented precision and internal consistency. The measured cross sections are compared to recent phase shift analyses, and their impact on the present solution SM97 [1] is discussed.

Isopentenyl diphosphate (IDP) and its isomer dimethylallyl diphosphate (DMADP) are building units for all isoprenoids; thus, intracellular pool sizes of IDP and DMADP play important roles in living organisms. Several methods have been used to quantify the amount of DMADP or the combined amount of IDP plus DMADP, but measuring the DMADP/IDP ratio has been difficult. In this study, a method was developed to measure the ratio of DMADP/IDP. Catalyzed by a recombinant IDP isomerase (IDI) together with a recombinant isoprene synthase (IspS), IDP was converted to isoprene, which was then detected by chemiluminescence. With this method, the in vitro equilibrium ratio of DMADP/IDP was found to be 2.11:1. IDP and DMADP pools were significantly increased in Escherichia coli transformed with methylerythritol 4-phosphate pathway genes; the ratio of DMADP/IDP was 3.85. An E. coli strain transformed with IspS but no additional IDI had a lower DMADP level and a DMADP/IDP ratio of 1.05. Approximately 90% of the IDP and DMADP pools in light-adapted kudzu leaves were light dependent and so presumably were located in the chloroplasts; the DMADP/IDP ratios in chloroplasts and cytosol were the same as the in vitro ratio (2.04 in the light and 2.32 in the dark).

Differential diagnosis of patients whose course of illness includes substantial psychotic and mood syndromes is among the most challenging in psychiatry. The relative temporal preponderance of one or the other of these syndromes over course of illness forms the basis for distinctions among DSM-III-R diagnoses of schizoaffective disorder (SA), bipolar disorder (BPD), and schizophrenia (SZ); and such temporal assessments may be especially difficult to make reliably. Elsewhere we report relatively low reliability of SA and a tendency for it be “confused” with SZ and BPD. In this paper, we identify clinical variables that increase diagnostic differentiation. Data are from a Diagnostic Interview for Genetic Studies (DIGS) reliability study in which patients with independently assessed DSM-III-R lifetime diagnoses of SA-bipolar subtype,(SA-BP), BPD, and SZ were also clinically assessed and diagnosed by the DIGS on two occasions by two different interviewers blind to entry diagnoses. The relative strength of DIGS-based DSM-III-R diagnoses and individual DIGS clinical variables in predicting entry diagnoses is shown in a series of logistic regression analyses. Models incorporating DIGS variables are more predictive of entry diagnoses than models using DIGS diagnoses alone. Based on DIGS information, the SA-BP group is more clearly differentiated from the BPD group than from the SZ group. Different profiles of DIGS variables distinguish the groups. Findings are discussed in terms of their implications for nosologic research. Depression 3:309–315 (1995/1996). © 1996 Wiley-Liss, Inc1 .

Dimethylallyl diphosphate (DMADP) is a central metabolite in isoprenoid metabolism, but it is difficult to measure. Three different methods for measuring DMADP are compared, and a new method based on the conversion of DMADP to isoprene using recombinant isoprene synthase is introduced. Mass spectrometry is reliable but does not distinguish between DMADP and isopentenyl diphosphate. Acid hydrolysis is reliable for measuring DMADP in bacterial extracts but overestimates DMADP in plant samples. To measure the DMADP in chloroplasts, light minus dark measurements are normally used. Chloroplast DMADP amounts measured using acid hydrolysis and a mass spectrometric method were comparable in this assay. Post-illumination isoprene emission tended to slightly overestimate chloroplast DMADP concentration. The DMADP pool size in bacteria is highly regulated, consistent with previous observations made with plants. DMADP is a very labile metabolite, but four methods described here allow measurements of samples from plants and bacteria. The use of recombinant isoprene synthase can greatly simplify the analysis. The various techniques tested here have advantages and disadvantages, and it is useful to have more than one method available when studying biological isoprene production.

A new understanding of leaf starch degradation has emerged in the last 10 years. It has been shown that starch phosphorylation and dephosphorylation are critical components of this process. Glucan, water dikinase (GWD) (and phosphoglucan, water dikinase) adds phosphate to starch, and phosphoglucan phosphatase (SEX4) removes these phosphates. To explore the use of this metabolism to manipulate starch accumulation, Arabidopsis (Arabidopsis thaliana) plants were engineered by introducing RNAi constructs designed to reduce expression of AtGWD and AtSEX4. The timing of starch build-up was altered with ethanol-inducible and senescence-induced gene promoters. Ethanol induction of RNAi lines reduced transcript for AtGWD and AtSEX4 by 50%. The transgenic lines had seven times more starch than wild type at the end of the dark period but similar growth rates and total biomass. Elevated leaf starch content in maize leaves was engineered by making an RNAi construct against a gene in maize that appeared to be homologous to AtGWD. The RNAi construct was expressed using the constitutive ubiquitin promoter. Leaf starch content at the end of a night period in engineered maize plants was 20-fold higher than in untransformed plants with no impact on total plant biomass. We conclude that plants can be engineered to accumulate starch in the leaves with little impact on vegetative biomass.

Primary metabolism in plants is tightly regulated by environmental factors such as light and nutrient availability at multiple levels. The circadian clock is a self-sustained endogenous oscillator that enables organisms to predict daily and seasonal changes. The regulation of primary metabolism by the circadian clock has been proposed to explain the importance of circadian rhythms in plant growth and survival. Recent transcriptomic and metabolomic analyses indicate a wide spread circadian regulation of different metabolic processes. We review evidence of circadian regulation of pathways in primary metabolism, discuss the challenges faced for discerning the mechanisms regulating circadian metabolic oscillations and present recent evidence of regulation of the circadian clock by metabolites.

Increasing the energy density of biomass by engineering the accumulation of triacylglycerols (TAGs) in vegetative tissues is synergistic with efforts to produce biofuels by conversion of lignocellulosic biomass. Typically, TAG accumulates in developing seeds, and little is known about the regulatory mechanisms and control factors preventing oil biosynthesis in vegetative tissues in most plants. Here, we engineered Arabidopsis thaliana to ectopically overproduce the transcription factor WRINKLED1 (WRI1) involved in the regulation of seed oil biosynthesis. Furthermore, we reduced the expression of APS1 encoding a major catalytic isoform of the small subunit of ADP-glucose pyrophosphorylase involved in starch biosynthesis using an RNAi approach. The resulting AGPRNAi-WRI1 lines accumulated less starch and more hexoses. In addition, these lines produced 5.8-fold more oil in vegetative tissues than plants with WRI1 or AGPRNAi alone. Abundant oil droplets were visible in vegetative tissues. TAG molecular species contained long-chain fatty acids, similar to those found in seed oils. In AGPRNAi-WRI1 lines, the relative expression level of sucrose synthase 2 was considerably elevated and correlated with the level of sugars. The relative expression of the genes encoding plastidic proteins involved in de novo fatty acid synthesis, biotin carboxyl carrier protein isoform 2 and acyl carrier protein 1, was also elevated. The relative contribution of TAG compared to starch to the overall energy density increased 9.5-fold in one AGPRNAi-WRI1 transgenic line consistent with altered carbon partitioning from starch to oil.

Carbon dioxide fixation is overwhelmingly carried out by reactions of the Calvin-Benson cycle of plants, green algae, and cyanobacteria. Three other carbon dioxide reduction pathways are known to allow autotrophic growth, but these are mainly limited to anaerobic organisms. In this chapter the anaerobic autotrophic carbon reduction pathways are briefly described followed by a more detailed look at the Calvin-Benson cycle and its regulation. The Calvin-Benson cycle reaction sequence is similar to the non-oxidative branch of the pentose phosphate pathway although the enzyme transaldolase of the pentose phosphate pathway is not used and a novel enzymatic activity, sedoheptulose 1,7-bisphosphatase is substituted. The carbon fixation enzyme of the Calvin-Benson cycle, Rubisco, varies in its properties and is currently the subject of much research aimed at improving the efficiency of photosynthesis. Rubisco exists in three different conformations and there is also a gene coding for a related protein that does not have Rubisco activity but could be the evolutionary progenitor. The Calvin-Benson cycle is often referred to as the dark reactions of photosynthesis but it does not proceed in darkness for several reasons. In addition to providing reducing power and ATP, photosynthetic electron transport causes increased pH and magnesium in the stroma plus reducing power for thioredoxin to activate Calvin-Benson cycle enzymes and inactivate enzymes that would lead to futile cycles when Calvin-Benson cycle enzymes are active. There is a surprising regulation of phosphoglucose isomerase that can shift the regulation of the rate of starch synthesis from ADPglucose pyrophosphorylase to phosphoglucose isomerase. This may control the amount of carbon that leaves the Calvin-Benson cycle, since excessive loss of carbon from the Calvin-Benson cycle intermediates can lead to a collapse of the cycle. Finally, a recently discovered regulation mechanism based on a small protein called CP12 is discussed.