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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ahj.2009.06.023 Byline: Michael Herman (a)(c), Jennifer Donovan (a)(c), Maichi Tran (a)(b)(c), Brigid McKenna (a)(b), Joel M. Gore (a)(b), Robert J. Goldberg (a)(b), Dennis A. Tighe (a)(b) Abstract: [beta]-Blockers have been shown to benefit patients after myocardial infarction by decreasing mortality, sudden cardiac death, and reinfarction. Although [beta]-blockers are recommended for all patients with acute coronary syndromes (ACS) without contraindications, a target heart rate (HR) is recommended only for patients with unstable angina/non ST-elevation myocardial infarction. A contemporary series documenting trends in [beta]-blocker usage and achieved HR and blood pressures (BP) is not available. The study objectives were to monitor trends in HR and BP in relation to [beta]-blocker use in a contemporary series of patients with ACS. Author Affiliation: (a) Division of Cardiovascular Medicine, UMass-Memorial Medical Center, Worcester, MA (b) Division of Cardiovascular Medicine, University of Massachusetts Medical School, Worcester, MA (c) Massachusetts College of Pharmacy and Health Sciences, Worcester, MA Article History: Received 26 February 2009; Accepted 13 June 2009

Abstract: Rheology of Ca-pectate gels is widely studied, but the behaviour of pectate gels formed by Cu, Al and La is largely unknown. It is well known that gel strength increases with increasing Ca concentration, and it is hypothesised that this would also be the case for other cations. Pectins are a critical component of plant cell walls, imparting various physicochemical properties. Furthermore, the mechanism of metal toxicity in plants is hypothesised to be, in the short term, related to metal interactions with cell wall pectin. This study investigated the influence of Ca, Cu, Al and La ion concentrations at pH 4 on the storage modulus as a function of frequency for metal-pectin gels prepared from pectin (1%) with a degree of esterification of 30%. Gels were formed in situ over 6d in metal chloride solution adjusted daily to pH 4. Cation concentration was varied to develop a relationship between gel strength and cation concentration. At similar levels of cation saturation, gel strength increased in the order of La

Background: β-Blockers have been shown to benefit patients after myocardial infarction by decreasing mortality, sudden cardiac death, and reinfarction. Although β-blockers are recommended for all patients with acute coronary syndromes (ACS) without contraindications, a target heart rate (HR) is recommended only for patients with unstable angina/non ST-elevation myocardial infarction. A contemporary series documenting trends in β-blocker usage and achieved HR and blood pressures (BP) is not available. The study objectives were to monitor trends in HR and BP in relation to β-blocker use in a contemporary series of patients with ACS. Methods: In this observational study, 300 consecutive patients with proven ACS had HR and BP values collected hourly from admission until hospital discharge and averaged at multiple intervals throughout hospital stay. Data on baseline demographic characteristics, β-blocker doses, and titration schedules, procedures performed, cardiac regimens, concurrent medical issues, and contraindications to therapy were collected. Results: Only 5.3% achieved an average HR of 50 to 60 beat/min throughout the hospital stay. Overall, the average HR was 74 beat/min and average BP was 115/64 mm Hg. Admission daily doses of metoprolol averaged 58 mg compared to discharge daily doses of 88 mg; only 52% of patients had dosage increases. Conclusions: Although effective levels of BP were maintained during hospitalization for an ACS, target HRs were generally not achieved. Future studies are needed to determine the relationship between treatment objectives and clinical outcomes in the present era of ACS management. [Copyright &y& Elsevier]

Highlights • A novel method using synchrotron-based micro X-ray fluorescence. • Provides laterally-resolved, multi-element, kinetic, in vivo analyses of plants. • Allows a wide range of studies for the examination of plant responses. Abstract The distribution and concentration of nutrients and contaminants affect almost every metabolic process in plants but analytical limitations have hindered the determination of microscopic changes over time within living plant tissues. We developed a novel method using synchrotron-based micro X-ray fluorescence (μ-XRF) that, for the first time, allows quantification of the spatial and temporal changes of multiple elements in the same area of living leaves. The utility of this approach was tested by examining changes over 48 h in unifoliate leaves of 7-d-old cowpea (Vigna unguiculata) plants simultaneously at 0.2 and 30 μM Mn in nutrient solution, with 30 μM Mn known to be toxic to cowpea and cause the formation of Mn-dense lesions. The fast X-ray fluorescence detector system reduced dwell on living leaf samples. This produced no evidence of tissue damage through repeated μ-XRF scanning, thereby overcoming previously noted experimental artifacts. This permitted, for the first time, visual and quantitative assessments of spatial and temporal changes in nutrient concentrations. By focusing on changes in Mn status, this study illustrated extension of two-dimensional μ-XRF scans to a three-dimensional geometry of Mn kinetics in the same area of leaves. The multi-element potential of this method was exemplified through the measurement of distributions and concentrations of K, Ca, Fe, Cu, and Zn within living plant leaves. This novel method and accompanying information on changes in Mn distribution showed the potential for microscopic, time-resolved, in vivo examination of changes in elemental distribution. We consider that this method will be of benefit for a wide range of studies, including functional characterization of molecular biology, examining changes in the distribution of nutrients, and understanding the movement and toxicity of contaminants. [ABSTRACT FROM AUTHOR]

Saline-sodic soils are often too saline and alkaline for plant survival. These soils are prone to dispersing and eroding after high rainfall events when salinity is reduced before the sodicity. Cost-effective and water efficient methods are needed to leach salts while maintaining sufficient ionic strength of the soil solution. We tested the ability of gypsum, both alone and combined with elemental sulfur and organic matter to remediate the upper 15 cm of a strongly saline-sodic alkaline Vertosol when leached with deionised water in repacked columns. Prior to leaching, all amendment combinations reduced soil alkalinity by 80% and dispersion by 47% by displacing exchangeable sodium (Na). After leaching with 600 mm of deionised water, electrical conductivity of the soil solution (EC ss) decreased from an average of 38–4.8 dS m−1 at 8 cm depth. Importantly, structure was maintained in all amended soils, despite this decrease in EC ss. In contrast, for the control treatment, there was a concomitant loss of soil structural stability as EC ss decreased. This decrease in stability also occurred in the subsoils of all treatments (which were not amended) because the applied calcium (Ca) precipitated before it could be leached to remediate the deeper layers. This study demonstrated that it was critical to first apply amendments as deep in the soil profile as possible to prevent the development of a non-saline sodic soil. Leaching the soil with low ionic strength water removed excess soluble salts from the plant root zone. We estimated that > 300 mm of water (rainfall or irrigation) was required to leach through the root zone to ensure a suitable soil profile for establishing of salt tolerant pioneer species such as Rhodes grass (Chloris gayana Kunth). • Little is known about remediating saline-sodic soils in subtropical climates. • Applying gypsum initially increased salinity but reduced alkalinity and sodicity. • Adding organic matter and sulfur with gypsum did not improve soil remediation. • Infiltrating 600 mm deionised water decreased salinity by 87% at 8 cm depth. • A growth zone for a pioneer plant species was created with 300 mm infiltration. [ABSTRACT FROM AUTHOR]

Abstract: Many metals and metalloids, jointly termed metal(loid)s, are toxic to plants even at low levels. This has limited the study of their uptake, distribution, and modes of action in plant roots grown at physiologically relevant concentrations. Synchrotron-based X-ray fluorescence microscopy was used to examine metal(loid)s in hydrated cowpea (Vigna unguiculata L.) roots exposed to Zn(II), Ni(II), Mn(II), Cu(II), Hg(II), Se(IV), Se(VI), As(III), or As(V). Development of a mathematical model enabled in situ quantitative determination of their distribution in root tissues. The binding strength of metals influenced the extent of their movement through the root cylinder, which influenced the toxic effects exerted—metals (e.g. Cu, Hg) that bind more strongly to hard ligands had high concentrations in the rhizodermis and caused this tissue to rupture, while other metals (e.g. Ni, Zn) moved further into the root cylinder and did not cause ruptures. When longitudinal distributions were examined, the highest Se concentration in roots exposed to Se(VI) was in the more proximal root tissues, suggesting that Se(VI) is readily loaded into the stele. This contrasted with other metal(loid)s (e.g. Mn, As), which accumulated in the apex. These differences in metal(loid) spatial distribution provide valuable quantitative data on metal(loid) physiology, including uptake, transport, and toxicity in plant roots. [Copyright &y& Elsevier]

• Soils are under increasing stress to feed a rapidly growing human population. • We show that soils are a master variable regulating critical Earth-system processes. • Soils make major contributions to biogeochemical flows and land-system change. • Soils also contribute to climate change, ocean acidification, and ozone depletion. • Improving management of soils is critical to maintain Earth in a hospitable state. We use soils to provide 98.8% of our food, but we must ensure that the pressure we place on soils to provide this food in the short-term does not inadvertently push the Earth into a less hospitable state in the long-term. Using the planetary boundaries framework, we show that soils are a master variable for regulating critical Earth-system processes. Indeed, of the seven Earth-systems that have been quantified, soils play a critical and substantial role in changing the Earth-systems in at least two, either directly or indirectly, as well as smaller contributions for a further three. For the biogeochemical flows Earth-system process, soils contribute 66% of the total anthropogenic change for nitrogen and 38% for phosphorus, whilst for the land-system change Earth-system process, soils indirectly contribute 80% of global anthropogenic change. Furthermore, perturbations of soils contribute directly to 21% of climate change, 25% to ocean acidification, and 25% to stratospheric ozone depletion. We argue that urgent interventions are required to greatly improve soil management, especially for those Earth-system processes where the planetary boundary has already been exceeded and where soils make an important contribution, with this being for biogeochemical flows (both nitrogen and phosphorus), for climate change, and for land-system change. Of particular importance, it is noted that the highly inefficient use of N fertilizers results in release of excess N into the broader environment, contributes to climate change, and results in release of ozone-depleting substances. Furthermore, the use of soils for agricultural production results not only in land-system change, but also in the loss (mineralization) of organic matter with a concomitant release of CO 2 contributing to both climate change and ocean acidification. Thus, there is a need to markedly improve the efficiency of fertilizer applications and to intensify usage of our most fertile soils in order to allow the restoration of degraded soils and limit further areal expansion of agriculture. Understanding, and acting upon, the role of soils is critical in ensuring that planetary boundaries are not transgressed, with no other single variable playing such a strategic role across all of the planetary boundaries. [ABSTRACT FROM AUTHOR]

Soils are the most complex and diverse ecosystem in the world. In addition to providing humanity with 98.8% of its food, soils provide a broad range of other services, from carbon storage and greenhouse gas regulation, to flood mitigation and providing support for our sprawling cities. But soil is a finite resource, and rapid human population growth coupled with increasing consumption is placing unprecedented pressure on soils through the intensification of agricultural production – the increasing of crop yield per unit area of soil. Indeed, the human population has increased from ca. 250 million in the year 1000, to 6.1 billion in the year 2000, and is projected to reach 9.8 billion by the year 2050. The current intensification of agricultural practices is already resulting in the unsustainable degradation of soils. Major forms of this degradation include the loss of organic matter and the release of greenhouse gases, the over-application of fertilizers, erosion, contamination, acidification, salinization, and loss of genetic diversity. This ongoing soil degradation is decreasing the long-term ability of soils to provide humans with services, including future food production, and is causing environmental harm. It is imperative that the global society is not shortsighted by focusing solely on the near-immediate benefits of soils, such as food supply. A failure to identify the importance of soil within increasingly intensive agricultural systems will undoubtedly have serious consequences for humanity and represents a failure to consider intergenerational equity. Of utmost importance is the need to unequivocally recognize that the degradation of soils leads to a clear economic cost through the loss of services, with such principles needing to be explicitly considered in economic frameworks and decision-making processes at all levels of governance. We contend that the concept of the Water-Food-Energy nexus must be expanded, forming the Water-Soil-Food-Energy nexus. • Soils provide humans with 98.8% of our food. • Rapid population growth is unprecedented pressure on soils. • Agricultural intensification is already degrading soils unsustainably. • This degradation is decreasing the long-term ability of soils to produce food. • The Water-Food-Energy nexus must be expanded to the Water-Soil-Food-Energy nexus. [ABSTRACT FROM AUTHOR]