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Context. Understanding the dynamics of soil organic matter (SOM) requires that it be divided into fractions with contrasting behaviour. Aim. Using soils from a field trial with a diverse set of treatments (pasture to arable conversion, ex-pasture soil maintained fallow for 13 years and arable cropping with contrasting tillage treatments), we evaluated two approaches to characterise SOM: particle-size fractionation and hot water extraction. Methods. Soils were separated into four size fractions, including the >50 [micro]m fraction (particulate organic matter, considered the most labile fraction) and the 50%) of the C lost under cropping and bare fallow was derived from the clay fraction, which was also the source of 59-77% of HWC. Conclusions and Implications. Our results indicate that hot water is specific for the labile component of SOM while SOM in size fractions is a composite of labile and stable components, the proportions of which may vary depending on land use and other factors. Ideally, data on quantity of SOM in size fractions should be complemented by information on its lability. Keywords: hot water extraction, labile C, land use effects, long-term fallow, particle size fractionation, pasture, soil organic matter, tillage., Introduction Soil organic matter (SOM) is vital to the health and functioning of soils. It also plays a central role in the global cycles of C and nutrients, including nitrogen [...]

Evidence is emerging that the solubility of soil organic matter (SOM) in water is a key factor regulating the turnover of carbon (C) and nitrogen (N). We used data from a field trial with a wide range of treatments in a case study to: (1) examine the link between SOM solubility and bioavailability and (2) evaluate whether low water-solubility is a factor contributing to the persistence of refractory SOM. The trial was established in 2000 on a silt loam (Udic Dystocrept) at Lincoln, New Zealand to identify management practices that maintain SOM following the conversion of long-term pasture to arable cropping. The following land use treatments were sampled (0-7.5, 7.5-15 and 15-25 cm) in 2013: (1) long-term ryegrass-white clover pasture; (2) arable cropping rotation, managed using either intensive, minimum, or no tillage; and (3) continuous bare fallow (plots maintained plant-free using herbicide; not cultivated). The bioavailability of SOM was determined by measuring C and N mineralisation in a 98-day incubation at 25[degrees]C (soil maintained near field capacity) and water solubility was assessed by measuring hot-water-extractable C and N (16-h extraction at 80[degrees]C). After 13 years of arable cropping, C stocks (to 25 cm) were 11 t [ha.sup.-1] less than in pasture soil (decrease of 14%). Tillage 'intensity' had no effect on C stocks in the top 25 cm. Large losses of C were observed in the bare fallow treatment (19 t C [ha.sup.-1] less than pasture soil). The bioavailability of SOM (C[O.sub.2]-C mineralised as a proportion of soil C) also declined under arable cropping and bare fallow. The relationship between total C and mineralised C had a significant (P < 0.001) intercept, indicating that part of the organic matter (13 g C [kg.sup.-1]) did not contribute to C mineralisation (it was biologically inert). Across treatments and sampling depths, SOM mineralised in 98 days generally corresponded well with that extracted in hot water. A significant fraction of SOM (~9 g C [kg.sup.-1]) did not release C to hot water. Water-insoluble organic matter, including compounds that are strongly bonded to mineral surfaces, may comprise a significant part of the refractory SOM. Keywords: bioavailability, land use effects, long-term fallow, recalcitrance, soil organic matter solubility., Introduction Soil organic matter (SOM) plays a central role in the global cycles of carbon (C) and nutrients, including nitrogen (N) (Powlson 1993; Janzen 2004; Stockmann el al. 2013). Knowledge [...]

The accelerated discovery and production of pharmaceutical products has resulted in many positive outcomes. However, this progress has also contributed to problematic polypharmacy, one of the rapidly growing threats to public health in this century. Problematic polypharmacy results in adverse patient outcomes and imposes increased strain and financial burden on healthcare systems. A review was conducted on the current body of evidence concerning factors contributing to and consequences of problematic polypharmacy. Recent trials investigating interventions that target polypharmacy and emerging solutions, including incorporation of artificial intelligence, are also examined in this article. To shift away from problematic polypharmacy, a multifaceted interdisciplinary approach is necessary. Any potentially successful strategy must be adapted to suit various healthcare settings and must utilize all available resources, including artificial intelligence. [ABSTRACT FROM AUTHOR]

Adverse drug reactions (ADRs) are frequent and represent a significant healthcare burden. ADRs are a potentially avoidable contributor to excess unscheduled hospital admissions, higher morbidity, mortality, and healthcare costs. The objective of this review is to examine the epidemiology of ADRs in older multimorbid adults and to explore strategies for ADR prevention. ADRs in this population are often linked to commonly prescribed medications, including anticoagulants, antiplatelet agents, insulin, and non-steroidal anti-inflammatory drugs, but ADRs and adverse drug events (ADEs) in fact encompass a much broader range of culprit drugs. Age-related factors such as changes in pharmacokinetics and pharmacodynamics, multimorbidity, polypharmacy, and frailty have been associated with ADR occurrences. Various strategies have been proposed to prevent ADRs in different clinical settings, such as structured routine medication review and the use of bespoke software applications to identify potentially inappropriate prescriptions and drug interactions. Although these approaches have demonstrated some improvement in the quality of prescribing, there is still a lack of consistent evidence regarding their effectiveness in preventing ADRs. The nuanced and often intricate complexities associated with older patients' pharmacotherapy necessitate a comprehensive approach to attenuate the impact of ADRs within this growing section of most populations globally. [ABSTRACT FROM AUTHOR]

Hot water is believed to extract bio-available soil organic matter (SOM), including organic compounds from the biomass of soil microbes. The role of soil physico-chemical factors in relation to extractability of SOM in hot water is not well understood. We evaluated the influence of exchangeable sodium (Na) on the quantity and quality of organic matter extracted in hot water from soils with a range of total and extractable C (total C 19-60 g [kg.sup.-1]; hot water extractable C (HWC) 659-3292 mg [kg.sup.-1]). The soils were pre-treated with different rates of Na (0-156 [cmol.sub.c] [kg.sup.-1], as NaCl) to establish a range of exchangeable Na percentages (ESP), and then extracted with hot water (80[degrees]C) for 16 h. Hot water extractable C increased linearly as ESP increased, but the rate of increase differed between soils (the increase in HWC per unit increase in ESP ranged within 19-71 mg [kg.sup.-1]). At ESP 15, a threshold used to separate sodic and nonsodic soils, HWC was 30-60% greater than that measured without added Na. Ultraviolet absorbance (260 nm) data indicated that aromatic organic matter was preferentially released following Na pre-treatment. The proportion of HWC in phenolic form was generally little affected by Na treatment but there was a consistent increase in protein in response to Na (hot water extractable organic N in protein form increased from an average of 5.5 [+ or -] 2.2% without added Na to 11.0 [+ or -] 3.6% at the highest Na rate). The Na-induced increases in UV absorbance may be largely attributable to release of proteins containing aromatic amino acids (tryptophan and tyrosine). Our results suggest that organic matter desorbed from mineral surfaces may be an important contributor to hot water extractable C and N, and factors that affect the adsorption-desorption process may significantly influence organic matter extractability in hot water. Additional keywords: chemical controls, dissolved protein and phenols, extractable organic matter, ultraviolet absorbance. Received 13 August 2019, accepted 18 February 2020, published online 31 March 2020, Introduction Dissolved organic matter is a labile component of soil organic matter (SOM) and a key driver of soil biological processes. The quantity of dissolved organic matter in soil is [...]

Soil rewetting can induce a flush of organic matter mineralisation, but the factors underpinning this mineralisation response are poorly understood. We investigated the effects of antecedent soil water content, before rewetting, on the quantity, quality and biodegradability of dissolved organic matter present in the leachate pore volumes from a soil under two different management histories: arable and grassland. Soils were collected at field capacity (FC) and dried to give four soil gravimetric water contents ([[theta].sub.g]): 22% (not dried, left at FC), 15%, 8% and Additional keywords: arable, dissolved organic carbon, biodegradation, drying and rewetting, grassland, [SUVA.sub.254]. Received 18 June 2018, accepted 21 February 2019, published online 29 March 2019, Introduction Dissolved organic matter (DOM) in soil solution is recognised as the most mobile (von Lutzow et al. 2007) and reactive (Haynes 2005) soil organic matter (SOM) fraction, and its [...]

In New Zealand, pastoral soils have substantial organic carbon (OC) stocks, which may be vulnerable to loss from disturbance and environmental perturbations. We assessed OC vulnerability using two approaches. For the first approach, we postulated that the OC deficit of continuously cropped soils relative to nearby pastoral soils would provide a measure of the quantity of potentially vulnerable OC in pastures. As a test, soils were sampled to a depth of 15 cm at 149 sites and the total organic carbon (TOC) and particulate organic carbon (POC) contents were measured. The second approach involved measurement of OC mineralisation in a laboratory assay (98 day aerobic incubation at 25[degrees]C). For the pastoral soils, the mean TOC and POC was about twice that of the cropped soils. On average, 89% more OC was mineralised from the pastoral soils compared with the cropped counterparts. However, the quantity of OC mineralised in pasture soils was small relative to the potential for OC loss inferred from the difference in TOC between pastoral and cropped soils. Carbon mineralisation was explained using a two-pool exponential model with rate constants of the 'fast' and 'slow' pools equating to 0.36 [+ or -] 0.155 and 0.007 [+ or -] 0.003 [day.sup.-1] respectively. The larger, slow OC pool correlated strongly with hot water extractable OC whereas the fast pool was related to OC extracted using cold water. Our results suggest that water extraction (using cold and hot water) can provide a rapid estimate of the quantity of mineralisable OC across a wide range of New Zealand soils. Additional keywords: C mineralisation, cropping, pasture SOC, vulnerability., Introduction Increasing soil organic carbon (SOC) has been identified as a potential strategy to off-set the increase in global greenhouse gas emissions (Lai 2004). Depending on a range of factors [...]

Key summary points: Aim: To update and validate STOPP/START criteria for potentially inappropriate prescribing. Findings: STOPP/START version 3 has been expanded and validated by an international European panel of experts in geriatric pharmacotherapy. Version 3, with 190 criteria, is significantly larger than version 2 (114 criteria), reflecting the expansion of the pharmacopeia and clinical trials evidence base relevant to older people since the publication of version 2. Message: STOPP/START version 3 represents an updated explicit list of potentially inappropriate medications and potential prescribing omissions aimed at optimizing medication and minimizing adverse drug reactions and events during medication review in older people, particularly those with multimorbidity and polypharmacy. Purpose: STOPP/START is a physiological systems-based explicit set of criteria that attempts to define the clinically important prescribing problems relating to potentially inappropriate medications (PIMs–STOPP criteria) and potential prescribing omissions (PPOs–START criteria). The previous two versions of STOPP/START criteria were published in 2008 and 2015. The present study describes the revised and updated third version of the criteria. Methods: A detailed system-by-system review of the published literature from April 2014 to March 2022 was undertaken with the aim of including clinically important new explicit PIM and PPO criteria and removing any criteria considered to be no longer correct or outdated. A panel of 11 academic physicians with recognized expertise in geriatric pharmacotherapy from 8 European countries participated in a Delphi panel with the task of validating the draft criteria. The panel was presented with the draft new criteria using the SurveyMonkey® on-line platform in which panelists were asked to indicate their level of agreement on a five-point Likert scale. Results: Two hundred and four evidence-based draft criteria (one hundred and forty-five STOPP criteria, fifty-nine START criteria) were presented to panelists for assessment using the Delphi validation method. Over the course of four rounds of Delphi validation, the panel achieved consensus on 133 STOPP criteria and 57 START criteria, i.e., 190 STOPP/START criteria in total representing a 66.7% increase in the number of criteria compared to STOPP/START version 2 published in 2015. Conclusion: A fully revised and updated version of STOPP/START criteria has been validated by a European expert panel using the Delphi consensus process. [ABSTRACT FROM AUTHOR]

Developing strategies to sequester carbon (C) in soils requires an understanding of the key factors that influence C stabilisation. Although fine mineral particles, especially clay, play a key role in stabilising soil organic matter (SOM), the relationship between SOM and texture is often not strong. We examined the role of the fine mineral fraction in C storage in sedimentary soils in New Zealand. Soils, representing two soil Orders (Brown and Recent) and different land use histories (total of 58 soils; 0-15 cm depth) were sampled. The concentration of C (and N) in four particle size fractions (50 µm) was determined (soils fractionated after dispersion by sonication). The soils had a wide range of textures and SOM; the mass proportion of clay (0.05) between the C concentration in whole soil and clay content. The concentration of C in the clay fraction, which varied over a wide range (35 to 135 g [kg.sup.-1] clay), decreased as the mass proportion of clay increased. A similar trend in C concentration was observed for the fine (5-20 µm) silt fraction. Because of this inverse relationship between the mass of the fine fractions and their C concentration, there was little change in amount of stable C (defined as C in the Additional keywords: C stabilisation by mineral particles, extractable Al & Fe, organic matter fractions., Introduction Soils play an important role in the global C cycle. Management practices that enhance soil C storage are frequently advocated as possible mitigation options to offset C[O.sub.2] emissions from [...]

Information on the pH buffer capacity of soil is required to estimate changes in pH due to acidic or alkaline inputs, and to model pH-dependent processes within the soil nitrogen (N) cycle. The objective was to determine whether a model based on soil organic matter (SOM) and mineral characteristics (clay content, extractable iron (Fe) and aluminium (Al)) would be adequate to estimate the buffer capacities of New Zealand soils. We measured pH changes in 34 soils, representing a range of SOM and texture, after equilibration with several rates (range 0-15 cmol O[H.sup.-][kg.sup.-1] soil) of either KOH or Ca[(OH).sub.2]. The Ca[(OH).sub.2] method often yielded higher buffer capacity values than the KOH method, possibly because of incomplete reaction of Ca[(OH).sub.2], especially at high addition rates. Buffer capacity (measured using KOH) of the soils was strongly correlated with soil carbon (C) (R2 = 0.76), and weakly (but significantly, P< 0.05) with clay content, and with dithionite extractable Fe and A1. A regression with soil C, clay, and P-retention (a surrogate for extractable A1 and Fe) as independent variables explained 90% of the variability in pH buffering. The role of organic matter was further evaluated by measuring buffer capacity of soil from research plots at Lincoln, Canterbury, New Zealand, that differed in C (21-37 g C [kg.sup.-1] in the top 7.5 cm; 19-26 g C [kg.sup.-1] in the 7.5-15 cm) as a result of the treatments imposed during the 12-year trial period. A substantial decrease in pH buffering (by up to 24% in top 7.5 cm) was associated with a decline in SOM following the conversion of permanent pasture (pre-trial land use) to arable cropping. Across all treatments and sampling depths, buffer capacity was linearly related ([R.sup.2] = 0.84, P< 0.001) to soil C; the estimated buffer capacity of SOM was 89 c[mol.sub.c] [kg.sup.-1] C pH [unit.sup.-1], similar to the value calculated from the previous study with different soil types. After 12 years, treatments with low soil C concentrations tended to be more acidic, possibly partly because of weaker pH buffering. Additional keywords: cation exchange capacity, phosphate retention, sesquioxides, soil C, texture, titratable acidity., Introduction Soils have the ability, to a greater or lesser extent, to resist changes in pH resulting from inputs of acid- or base-forming substances. Soil acidification has been a long-term [...]

Conventional, fixed-depth sampling may lead to errors in quantifying temporal changes in C stocks if soil bulk density (BD) changes. When surface elevation is altered due to a change in BD, sampling depth should be adjusted so that the sampled soil mass remains constant. We evaluated the ability of a topographic survey method (precise level) to quantify temporal changes (2000-2007) in surface elevation following conversion of long-term pasture to arable cropping using conventional tillage (plowing to 20 cm), minimum tillage, or no-till. Measured elevations were compared with values estimated from BD determined for fixed-depth increments (0-7.5, 7.5-15,15-25, and 25-30 cm). In the first season, soil mass to 25 cm decreased by ~270 Mg/ha under conventional cultivation (relative to precultivation mass of 3345 Mg/ha) as BD decreased in the 7.5- to 15- and 15- to 25-cm layers. This represented an upward movement of the soil surface by an estimated 22 mm. Minimum tillage and no-till treatments moved 9 and 2 mm upward, respectively. Subsequently, the soil consolidated and surface elevation declined by an estimated 8 mm in all cultivated treatments. Elevation changes measured by the precise level were very similar to these BDbased estimates. Changes in elevation in conventional, minimum tillage, and no-till treatments averaged 13, 1.5, and -6 mm, respectively (positive values indicate upward movement, negative values subsidence). Corresponding BD-estimated values were 17, 1.1, and -3 mm. Using topographic survey information, sampling depth can be adjusted so that a constant mass is sampled from soils where BD has been changed by tillage or natural processes. doi: 10.2136/sssaj2009.0251

Cold (room temperature) and hot water (70-80[degrees]C) extraction methods have been used to assess the availability of organic matter and N in soil; however, the influence of temperature on their extractability is largely unknown. Twenty-one mineral soils from New Zealand and eastern Canada were incubated for 16 h in water (1:6 soil/water ratio) at temperatures ranging from 20 to 80[degrees]C. After centrifugation and removal of the supernatant solution, the soil residue was extracted with 2 tool [L.sup.-1] KCl to recover N[H.sub.4]-N released during incubation. In all cases, water-extractable organic C (WEOC) and N (WEON) increased exponentially with temperature. The temperature dependence of organic matter solubility differed considerably among the soils (estimated increase in WEOC and WEON: 1.1-5.3% [degrees][C.sup.-1]). These differences were not explained by management history or soil physicochemical properties, although there was evidence that organic matter extractability in some clay soils was less sensitive to temperature. Ammonium N was released in significant amounts at all temperatures. Peak N[H.sub.4]-N release typically occurred at 50[degrees]C, where N[H.sub.4]-N comprised an average of 49% of the total recovered N (WEON plus N[H.sub.4]-N). Factors that may account for N[H.sub.4]-N production during the 16-h incubation include mineralization at the lower temperatures and abiotic processes (e.g., release of clay-fixed N[H.sub.4] and thermal degradation of organic N) at higher temperatures. The possibility that mineralization made a significant contribution to N[H.sub.4]-N production at temperatures as high as 50[degrees]C warrants further investigation. Abbreviations: WEOC, water-extractable organic carbon; WEOM, water-extractable organic matter; WEON, water-extractable organic nitrogen. doi:10.2136/sssaj2008.0347