The selective extraction of the hydrophilic sulfate ion from water is highly challenging because the high free energy of hydration of this ion makes it more difficult to extract than less hydrophilic ...ions such as chloride and nitrate. Lipophilic macrocyclic squaramide receptors
1
and
2
were synthesized. Receptor
2
efficiently extracted sulfate from aqueous sodium sulfate solutions into a chloroform phase,
via
exchange with nitrate ions, overcoming the Hofmeister bias. The resulting
2
·SO
4
2−
complex was readily recycled through precipitation of BaSO
4
. Transport of sulfate across a bulk chloroform membrane by
2
was demonstrated across a wide pH range (pH 3.2-9.4) and in the presence of high concentrations of competing anions (chloride, nitrate and dihydrogenphosphate), opening the door to the use of
2
for the selective removal of sulfate from water across a range of applications.
Lipophilic macrocycles efficiently extract sulfate ions from water into chloroform and transport this ion across a bulk liquid membrane in the presence of competing anions (chloride, nitrate and dihydrogenphosphate).
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IJS, KILJ, NUK, UL, UM, UPUK
Institute for Biomedical Research, Muscle Research Unit, Department
of Anatomy and Histology, University of Sydney, Sydney,
Australia
Dos Remedios, C. G.,
D. Chhabra,
M. Kekic,
I. V. Dedova,
M. ...Tsubakihara,
D. A. Berry, and
N. J. Nosworthy.
Actin Binding Proteins: Regulation of Cytoskeletal
Microfilaments. Physiol. Rev. 83: 433-473, 2003. The actin cytoskeleton is a complex
structure that performs a wide range of cellular functions. In 2001, significant advances were made to our understanding of the structure
and function of actin monomers. Many of these are likely to help us
understand and distinguish between the structural models of actin
microfilaments. In particular, 1 ) the structure of actin was
resolved from crystals in the absence of cocrystallized actin binding
proteins (ABPs), 2 ) the prokaryotic ancestral gene of actin
was crystallized and its function as a bacterial cytoskeleton was
revealed, and 3 ) the structure of the Arp2/3 complex was
described for the first time. In this review we selected several ABPs
(ADF/cofilin, profilin, gelsolin, thymosin 4, DNase I, CapZ,
tropomodulin, and Arp2/3) that regulate actin-driven assembly,
i.e., movement that is independent of motor proteins. They were chosen
because 1 ) they represent a family of related proteins,
2 ) they are widely distributed in nature, 3 ) an
atomic structure (or at least a plausible model) is available for each
of them, and 4 ) each is expressed in significant quantities
in cells. These ABPs perform the following cellular functions:
1 ) they maintain the population of unassembled but assembly-ready actin monomers (profilin), 2 ) they
regulate the state of polymerization of filaments (ADF/cofilin,
profilin), 3 ) they bind to and block the growing ends of
actin filaments (gelsolin), 4 ) they nucleate actin assembly
(gelsolin, Arp2/3, cofilin), 5 ) they sever actin filaments
(gelsolin, ADF/cofilin), 6 ) they bind to the sides of actin
filaments (gelsolin, Arp2/3), and 7 ) they cross-link
actin filaments (Arp2/3). Some of these ABPs are essential, whereas
others may form regulatory ternary complexes. Some play crucial roles
in human disorders, and for all of them, there are good reasons why
investigations into their structures and functions should continue.
Climate models incorporate photosynthesis-climate feedbacks, yet we lack robust tools for large-scale assessments of these processes. Recent work suggests that carbonyl sulfide (COS), a trace gas ...consumed by plants, could provide a valuable constraint on photosynthesis. Here we analyze airborne observations of COS and carbon dioxide concentrations during the growing season over North America with a three-dimensional atmospheric transport model. We successfully modeled the persistent vertical drawdown of atmospheric COS using the quantitative relation between COS and photosynthesis that has been measured in plant chamber experiments. Furthermore, this drawdown is driven by plant uptake rather than other continental and oceanic fluxes in the model. These results provide quantitative evidence that COS gradients in the continental growing season may have broad use as a measurement-based photosynthesis tracer.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
The capacity of species to respond adaptively to warming temperatures will be key to their survival in the Anthropocene. The embryos of egg-laying species such as sea turtles have limited behavioural ...means for avoiding high nest temperatures, and responses at the physiological level may be critical to coping with predicted global temperature increases. Using the loggerhead sea turtle (Caretta caretta) as a model, we used quantitative PCR to characterise variation in the expression response of heat-shock genes (hsp60, hsp70 and hsp90; molecular chaperones involved in cellular stress response) to an acute non-lethal heat shock. We show significant variation in gene expression at the clutch and population levels for some, but not all hsp genes. Using pedigree information, we estimated heritabilities of the expression response of hsp genes to heat shock and demonstrated both maternal and additive genetic effects. This is the first evidence that the heat-shock response is heritable in sea turtles and operates at the embryonic stage in any reptile. The presence of heritable variation in the expression of key thermotolerance genes is necessary for sea turtles to adapt at a molecular level to warming incubation environments.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Aim: To test the extent to which the vertical structure of tropical forests is determined by environment, forest structure or biogeographical history. Location: Pan-tropical. Methods: Using height ...and diameter data from 20,497 trees in 112 non-contiguous plots, asymptotic maximum height (H AM ) and height—diameter relationships were computed with nonlinear mixed effects (NLME) models to: (1) test for environmental and structural causes of differences among plots, and (2) test if there were continental differences once environment and structure were accounted for; persistence of differences may imply the importance of biogeography for vertical forest structure. NLME analyses for floristic subsets of data (only/excluding Fabaceae and only/excluding Dipterocarpaceae individuals) were used to examine whether family-level patterns revealed biogeographical explanations of cross-continental differences. Results: H AM and allometry were significantly different amongst continents. H AM was greatest in Asian forests (58.3 ± 7.5 m, 95% CI), followed by forests in Africa (45.1 ± 2.6 m), America (35.8 ± 6.0 m) and Australia (35.0 ± 7.4 m), and height—diameter relationships varied similarly; for a given diameter, stems were tallest in Asia, followed by Africa, America and Australia. Precipitation seasonality, basal area, stem density, solar radiation and wood density each explained some variation in allometry and H AM yet continental differences persisted even after these were accounted for. Analyses using floristic subsets showed that significant continental differences in H AM and allometry persisted in all cases. Main conclusions: Tree allometry and maximum height are altered by environmental conditions, forest structure and wood density. Yet, even after accounting for these, tropical forest architecture varies significantly from continent to continent. The greater stature of tropical forests in Asia is not directly determined by the dominance of the family Dipterocarpaceae, as on average non-dipterocarps are equally tall. We hypothesise that dominant large-statured families create conditions in which only tall species can compete, thus perpetuating a forest dominated by tall individuals from diverse families.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
It is widely accepted that climate change poses severe threats to freshwater ecosystems. Here we examine the scientific basis for adaptively managing vulnerable habitats and species. Our views are ...shaped by a literature survey of adaptation in practice, and by expert opinion. We assert that adaptation planning is constrained by uncertainty about evolving climatic and non-climatic pressures, by difficulties in predicting species- and ecosystem-level responses to these forces, and by the plasticity of management goals. This implies that adaptation measures will have greatest acceptance when they deliver multiple benefits, including, but not limited to, the amelioration of climate impacts. We suggest that many principles for biodiversity management under climate change are intuitively correct but hard to apply in practice. This view is tested using two commonly assumed doctrines: “increase shading of vulnerable reaches through tree planting” (to reduce water temperatures); and “set hands off flows” (to halt potentially harmful abstractions during low flow episodes). We show that the value of riparian trees for shading, water cooling and other functions is partially understood, but extension of this knowledge to water temperature management is so far lacking. Likewise, there is a long history of environmental flow assessment for allocating water to competing uses, but more research is needed into the effectiveness of ecological objectives based on target flows. We therefore advocate more multi-disciplinary field and model experimentation to test the cost-effectiveness and efficacy of adaptation measures applied at different scales. In particular, there is a need for a major collaborative programme to: examine natural adaptation to climatic variation in freshwater species; identify where existing environmental practice may be insufficient; review the fitness of monitoring networks to detect change; translate existing knowledge into guidance; and implement best practice within existing regulatory frameworks.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The survival and viability of sea turtle embryos is dependent upon favourable nest temperatures throughout the incubation period. Consequently, future generations of sea turtles may be at risk from ...increasing nest temperatures due to climate change, but little is known about how embryos respond to heat stress. Heat shock genes are likely to be important in this process because they code for proteins that prevent cellular damage in response to environmental stressors. This study provides the first evidence of an expression response in the heat shock genes of embryos of loggerhead sea turtles (Caretta caretta) exposed to realistic and near-lethal temperatures (34°C and 36°C) for 1 or 3 hours. We investigated changes in Heat shock protein 60 (Hsp60), Hsp70, and Hsp90 mRNA in heart (n=24) and brain tissue (n=29) in response to heat stress. Under the most extreme treatment (36°C, 3h), Hsp70 increased mRNA expression by a factor of 38.8 in heart tissue and 15.7 in brain tissue, while Hsp90 mRNA expression increased by a factor of 98.3 in heart tissue and 14.7 in brain tissue. Hence, both Hsp70 and Hsp90 are useful biomarkers for assessing heat stress in the late-stage embryos of sea turtles. The method we developed can be used as a platform for future studies on variation in the thermotolerance response from the clutch to population scale, and can help us anticipate the resilience of reptile embryos to extreme heating events.
•Sea turtle embryos produce a thermotolerance response to acute heat stress.•Thermotolerance response was measured by differential expression of heat shock protein genes Hsp60, Hsp70, and Hsp90.•Hsp60 mRNA produced a modest change in expression in brain tissue.•Hsp70 and Hsp90 mRNA increased expression in heart and brain tissue.•Hsp70 and Hsp90 mRNA are good biomarkers for response to acute heat stress.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The aim of this study was to collate and review the peer and non-peer reviewed English language literature on the treatment and prevention of foot lameness in cattle published since January 2000. The ...study aimed to identify deficits in knowledge and areas of disparity between what is recommended in the field by veterinarians, foot trimmers and advisors and what has been substantiated experimentally. Peer reviewed literature containing original work was gathered by searching three databases. Papers were categorised and reviewed if they contained material on treatment or prevention. Non-peer reviewed clinical materials were collated from a range of sources. The materials were reviewed and categorised based on whether they recommended a range of possible treatment and prevention strategies.
The peer reviewed data base contained 591 papers, of which 286 contained information on treatment or prevention. The vast majority of papers (258) concerned prevention; only a small number covered treatment (31) and of these only three contained information on the treatment of sole ulcers or white line disease. The number of intervention studies and trials was low; most papers on prevention were observational. Generally, lesion specific outcomes were not described making the findings of these papers difficult to use clinically. The non-peer reviewed material contained 46 sources; they varied significantly in regard to the treatments they advocated with some texts directly contradicting each other. Some aspects of prevention recommended in these sources seemed poorly supported by findings from the research literature. Well designed intervention studies are required to address these deficits.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With ...Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimizing pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed.
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