Optimizing photorespiration for improved crop productivity

In C3 plants, photorespiration is an energyexpensive process, including the oxygenation of ribulose-1,5-bisphosphate(RuBP) by ribulose 1,5-bisphosphate carboxylase/oxygenase(Rubisco) and the ensuing multiorganellar photorespiratory pathway required to recycle the toxic byproducts and recapture a portion of the fixed carbon. Photorespiration significantly impacts crop productivity through reducing yields in C3 crops by as much as 50%under severe conditions. Thus, reducing the flux through, or weive R improving the efficiency of photorespiration has the potential of large improvements in C3 crop productivity.Here, we review an array of approaches intended to engineer photorespiration in a range of plant systems with the goal of increasing crop productivity. Approaches include optimizing flux through the native photorespiratory pathway, installing non-native alternative photorespiratory pathways, and lowering or even eliminating Rubiscocatalyzed oxygenation of RuBP to reduce substrate entrance into the photorespiratory cycle. Some proposed designs have been successful at the proof of concept level.A plant systems-engineering approach, based on new opportunities available from synthetic biology to implement in silico designs, holds promise for further progress toward delivering more productive crops to farmer's fields.     

Generating spatial data for marine conservation and management

Do fishers know best when it comes to identifying areas with rare and depleted fish species? The global conservation crisis demands that managers marshal all available datasets to inform conservation management plans for depleted species, yet the level of trust placed in local knowledge remains uncertain. This study compares four methods for inferring species distributions of an internationally traded, rare and depleted genus of marine fishes (Hippocampus spp.): the use of (i) fisher interviews; (ii) government research trawls, (iii) scientific diving surveys, and (iv) citizen science contributions. We analyzed these four datasets at the genus and individual species levels to evaluate our conclusions about seahorse spatial occurrence, diversity of species present and the cost effectiveness of sampling effort. We found that fisher knowledge provided more information on our data-poor fish genus at larger spatial scales, with less effort, and for a cheaper price than all other datasets. One drawback was that fishers were unable to provide data down to the species level. People embarking on conservation endeavors for data-poor species may wish to begin with fisher interviews and use these to inform the application of government research, scientific diving, or citizen science programs.     

Design,synthesis and SAR of substituted indoles as selective TrkA inhibitors

A series of substituted indoles were examined as selective inhibitors of tropomyosin-related kinase receptor A (TrkA), a therapeutic target for the treatment of pain. An SAR optimization campaign based on ALIS screening lead compound 1 is reported.     

Variations in carbon-to-phosphorus ratios of two Australian strains of Cylindrospermopsis raciborskii

The toxic cyanobacterium Cylindrospermopsis raciborskii can form large blooms in freshwater systems, causing water quality problems. The availability of the essential macronutrient phosphorus (P), has a big impact on bloom formation but the variation in physiological response of different strains of C. raciborskii to available P has not previously been examined. This study investigated the carbon:phosphorus (C:P) ratio of two toxic Australian strains of C. raciborskii, AWT205 and NPD, under a range of P concentrations in batch and continuous cultures. P was added as a single dose to batch cultures and in continuous cultures at P concentrations of 0.032, 0.16, 0.64 and 16 μmol P l^?1. Cellular carbon and phosphorus content of both strains increased under P-limited conditions (0 μmol P l^?1 addition) with zero growth. Strain NPD had a lower C:P ratio (34:1) than AWT205 (150:1) indicating higher P storage capacity, and strain NPD survived P-limited conditions for longer. There was no significant difference in exponential growth rates (0.2 d^?1, P ≥ 0.5) under all P concentrations for both strains, with the exception of no P, demonstrating non-P-limited growth even at the lowest concentration (0.032 µmol P l^?1) and no increase in growth rate with additional P. ³³P uptake measurements were used to show that these strains both have very low half saturation constants (K_s = 0.02 μmol P l^?1) compared with other phytoplankton and strains of C. raciborskii. This is indicative of high uptake affinities and suggests that these strains are highly adapted to a low P supply. Overall the results of this study are consistent with the P strategy of storage prioritization over growth rate, and demonstrate differences between the strains in the C:P ratio under P-limitation, indicating variation in P storage.     

New Zealanders working non-standard hours also have greater exposure to other workplace hazards

Exposure to workplace hazards, such as dust, solvents, and fumes, has the potential to adversely affect the health of people. However, the effects of workplace hazards on health may differ when exposure occurs at different times in the circadian cycle, and among people who work longer hours or who do not obtain adequate sleep. The aim of the present study was to document exposures to workplace hazards across a national sample of New Zealanders, comparing people who work a standard 08:00 ?17:00 h Monday-to-Friday working week (Std hours) and those who do not (N-Std hours). New Zealanders (n = 10 000) aged 20–64 yrs were randomly selected from the Electoral Roll to take part in a nationwide survey of workplace exposures. Telephone interviews were conducted between 2004 and 2006, using a six-part questionnaire addressing demographics, detailed information on the current or most recent job (including exposures to a range of workplace hazards), sleep, sleepiness, and health status. N-Std hours were categorised on the basis of: being required to start work prior to 07:00 h or finish work after 21:00 h and/or; having a regular on-call commitment (at least once per week) and/or; working rotating shifts and/or; working night shift(s) in the last month. The response rate was 37% (n = 3003), with 22.2% of participants (n = 656) categorised as working N-Std hours. Industry sectors with the highest numbers of participants working N-Std hours were manufacturing, health and community services, and agriculture, fishing, and forestry. Response rate was 37% (n = 3003) with 22.2% (n = 656) categorised as working N-Std hours. Participants working N-Std hours were more likely to be exposed to all identified hazards, including multiple hazards (OR = 2.45, 95% CI = 2.01–3.0) compared to those working Std hours. Participants working N-Std hours were also more likely to report ‘never/rarely’ getting enough sleep (OR = 1.38, 95% CI = 1.15–1.65), ‘never/rarely’ waking refreshed (OR = 1.23, 95% CI = 1.04–1.47), and excessive sleepiness (OR = 1.77, 95% CI = 1.29–2.42). New Zealanders working N-Std hours are more likely to be exposed to hazards in the workplace, to be exposed to multiple hazards, and to report inadequate sleep and excessive sleepiness than their colleagues working a standard 08:00?17:00 h Monday-to-Friday working week. More research is needed on the effects of exposure to hazardous substances outside the usual waking day, on the effects of exposure to multiple hazards, and on the combination of hazard exposure and sleep restriction as a result of shift work.     

Age-associated differences in motor output variability and coordination during the simultaneous dorsiflexion of both feet

Older adults are more variable than young adults on tasks that demand the simultaneous control of more than one effector, and the difference between age groups may be related to their different capacity of coordinating the force output of the involved effectors. The goal of this study was to determine whether age-associated differences in motor output variability during tasks involving the simultaneous dorsiflexion of two feet can be partially explained by differences in coordination and possibly attenuated by physical training. Ten young and 22 old adults (10 trained and 12 untrained old adults) volunteered to participate in the study. Trained older adults had experience in a high-intensity mixed modality training (MMT) regime for a minimum of 1?year. Volunteers performed successive trials of a constant force task and a goal-directed task, with and without visual feedback. Within- and between-trial variability were calculated and coordination was quantified using the uncontrolled manifold (UCM) approach (i.e., co-variation of the force outputs of both feet were used to quantify a motor synergy index). Older adults exhibited greater variability and lower synergy (p?p?相似文献   

Whole genome sequencing reveals a 7 base-pair deletion in DMD exon 42 in a dog with muscular dystrophy

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